Photosynthesis- Earth's Life Support System

According to the geological history, photosynthesis is thought have occurred roughly 3.5 billion years ago.

Dead Zone

Death of fisheries due to uncontrolled algal growth leads to 'dead zones'. U.S. waters have the largest dead zones off the Mississippi delta.

Gingko: a not-so-safe herbal medicine for Epilepsy

Scientific evidences show that G. biloba may increase the risk of seizures in people with epilepsy.

The Science behind weight loss

You can add 20-plus great years to your life by making simple lifestyle changes.

Dealing with public toddler tantrumms

Tips which will help you lower down the frequency of such mortifying episodes.

Wednesday, January 29, 2014

Zinc Plating


Zinc, which has a distinctive bluish-white tinge and a brilliant shine, is one of the most extensively used metals in the surface finishing industry.

Zinc plating provides a soft and anti-corrosive covering around the substrate, preventing
oxidation of the substrate (metal that is to be guarded) by forming a protective anti-corrosive barrier around it. Unlike other metal plating techniques, it actually shields the object by acting as a sacrificial coating that prolongs the life of the basis metal, which – when exposed – gets effected before the object and therefore prevents its corrosion. It is also known as electroplating or galvanization.

What makes it particularly popular commercially is the fact that it is not only very effective but also amongst the most affordable forms of plating.

Zinc Plating is also done in combination with other metals like nickel, cobalt and tin for zinc plating. Zinc plating is however most widely used commercially for plating iron and steel, but is also used to protect finished products – ranging from structural steelwork for buildings and bridges, to nuts, bolts, screws, strips, sheets, wires and tubes.

Commercial Uses of Zinc Plating

Automobiles

Zinc plating technology has been used in the automotive industry for a long time across Japan, Europe and USA. It primarily uses zinc-nickel coatings for most of its products. The plated end products may finally be used in passenger car and light truck power steering components, air conditioning, hydraulic brake components and, in general, for most under-the-hood components.

Electrical Transmission

Many zinc plating processes have been extensively used for heavy electrical transmission components.

Metal parts or structures that are used in engineering products or for the purpose of providing linkages and anchorage, and therefore having a propensity to be excessively exposed to natural elements or oxidation or chemical corrosion, are ideal candidates for zinc plating. Good examples of such cases would be nuts and bolts, ship anchors or cleats, or for that matter, any metal fixtures that spend majority of their productive life on the highways or the high seas. Zinc plating on such objects gives additional protection by providing a highly resistant anti-corrosive film, thus increasing their longevity.

Another popular use of zinc plating is in the coaxial TV cable connector, which is assembled within the aluminum hosing. These connectors are used both indoors and outdoors. Alkaline zinc-nickel plating used here is actually also an environmentally safer substitute.

Fasteners

This is another industry which heavily depends on plating. Traditionally, cadmium has been used for plating, but it is not environment friendly and it’s anti corrosion property breaks down when exposed to heat. This has therefore given way to zinc plating as a much better option. Plating fasteners in zinc- nickel plating is therefore now a fast- growing industry.

Defence




Zinc plating is also finding its due place in manufacturing of tanks and armored personnel carriers, with additional research going on in this area so as to find new avenues of its application.


Definition of Plant Cloning

Plant cloning has been in practice since ages. It is an ancient form that allows the gardener to produce desired genetically identical plant from its parent plant. The resulting clone will have all the characteristics of the parent plant including growth habit, resistance towards various diseases, color of the flower, shape of the fruit as well as total yield of the plant. Also, the complete cloning process becomes easier with the asexual ability of the plants to replicate or multiply themselves. 

Method


The method of making a cutting of the desired plant for cloning is relatively easy-
* Firstly, select the stem or branch of the parent plant that has 2-3 sets of leaves.
* Leave 2 sets of nodes above the cut. Remove the larger leaves from the stem as they will be difficult to manage by a stem without roots.
* Dip the base of the cutting into a cloning gel (like Olivia’s) to prevent embolism.
* Place the cutting into the growing medium with at least half inch of the cutting below the growing surface.

Factors influencing proper growth of the cutting


Parent stock- The condition of the plant at the time of cutting is vital to plant cloning. Good quality mother plant produces better yielding and disease resistant clones as compared to stressed out plants. Also, the mother plant should be kept in vegetative state and replaced every year as cuttings from younger plants root easier than those which are a few years older.

Growing medium- Planters should chose those growing mediums that are allow free entry of oxygen and also retain less water.

Rooting hormone- For easy rooters, Olivia’s cloning gel should be used. Clonex should be used as a rooting medium for cuttings that are difficult to root.

Water quality- Water quality is often ignored during plant cloning. Water must contain required minerals for cuttings during the rooting process. pH of the water should be balanced (6-6.3).

Temperature- The ideal temperature range for cuttings is 72 degree Fahrenheit- 80 degree Fahrenheit.

Humidity- The ideal humidity range for cuttings is 70-80%. Low humidity will fasten the process of transpiration from young cuttings than they can absorb from the growing medium.

Light- Fluorescent light is best suited for cuttings as it is a soft light and has the right balance of red and blue spectrum.

CO2- CO2 is required by the leaves of the cutting as they absorb it and along with water, converts it into sugars.

Aeration- Roots require dissolved oxygen for proper growth of the cutting.

Cloning Machines


Some of the available cloning machines in market are Power Cloner by American Agritech, EZ clone by EZ clone and Clone Machine by American Agritech.

Advantages and Disadvantages


The major advantage of plant cloning over multiplication via seeds is that the gardener knows the type of plant they will get as a result of this cloning. However, plant cloning restricts the diversity of the plant, making it prone to various pests and diseases.

Tuesday, January 28, 2014

Infrared Thermometers


Thermometers that tell the temperature by measuring radiation from an object are called infrared thermometers. These thermometers have a lens that focuses the infrared energy on to a device that converts it into an electrical signal and passes it on to a display panel, which has been calibrated to show the measurement in temperature units. Key advantage of such thermometers is their ability to measure temperature without coming in contact with the object, as radiation energy can be measured from a distance. This is particularly useful in situations where it may not be possible to measure temperature using conduction techniques, such as in industrial applications with very high temperatures or in complex mechanical assemblies with no direct accessibility.

Uses of infrared thermometers

Applications in and around the house

Infrared thermometers can help assess the quality of insulation in construction works such as walls, pipes and windows. They can also be used to ascertain room temperatures or thermostat settings in heating and cooling systems. In greenhouses and outdoor gardens, they may be used to inspect the soil temperatures.

In the kitchen, infrared thermometers can be used to check pantry, refrigerator and freezer temperatures. While cooking food, they can be used for verification of cooking and serving temperatures as well. Another use of these thermometers can be to accurately measure temperatures during preparation and storage stages of wine and beer making, as these processes are temperature sensitive.

Infrared thermometers can also be useful while inspecting problems in household electrical or mechanical appliances. By measuring temperatures of typical heating points and ascertaining abnormal sources of heating, a quick diagnosis can be made.
Infrared thermometers can also find uses in pursuing hobbies such as photography, as developing of prints requires a control over the ambiance temperature.

Applications in automotive and transportation industry


Engine and exhaust troubleshooting in automobiles can be effectively carried out using infrared thermometers. For instance, low compression and ignition problems can be identified by scanning the manifold temperature. Incorrect fuel/air mixture leads to inefficient combustion, which can be determined by measuring the temperature of exhaust system components.

Diagnostics of cooling systems, radiators, climate control sensors and other devices that operate on temperature gradient can be carried out using infrared thermometers. Similarly, in brake system of automobiles, very high temperatures of rotors, drums or bearings indicate excessive wear and can be measured using an infrared thermometer.

Applications in electrical and electronics industry


In electrical devices and components such as connectors, motors, bearings, transformers and batteries, any abnormal heating is indicative of malfunctioning. Since infrared thermometers measure the surface temperature of an object from a distance, they can be extremely useful in preventive maintenance operations, while also ensuring that they are carried out in a safe manner.

Monday, January 27, 2014

Uses of Silver Oxide

A chemical compound, silver oxide (Ag2O) is a fine, dry powder with a characteristic brownish-black color and is used in the preparation of other silver compounds. It is a three-dimensional polymer and is not readily soluble in most solvents. Although, Ag2O hydrolyses only slightly in water, it imparts the water a distinctive metallic taste. However, silver oxide is soluble in dilute nitric acid and is easily attacked by acids. Like other silver compounds, silver oxide is not light sensitive and decomposes at temperatures above 280 degree C.

Uses of Silver Oxide
As laboratory reagent
Silver oxide is used as a reagent in a number of laboratory reactions to form various compounds. It dissolves in ammonium hydroxide solutions to give soluble derivatives. Also, silver oxide reacts with alkali chloride solutions to yield alkali hydroxide.  Ag2O is often employed in the synthesis of transition metal-carbene complexes (silver oxide readily reacts with ligand precursors to form the corresponding complexes).

As carbon dioxide sorber (scrubber)
Silver oxide is very effective in removing (or scrubbing) carbon dioxide from humidified air (humidity greater than 25%). This property is extensively used in space missions (by nuclear submarines, international space station and space shuttle).  Silver oxide reacts with carbon dioxide in the presence of water to generate silver carbonate. Further, it is capable of regenerating all the sorbed CO2 by prolonged heating which enables each canister to be recycled about 60 times.

In pollution control filters
Silver oxide is also used in the manufacture of filters for gas sensors. This filter helps in increasing the efficiency of chlorine dioxide detectors to free the gas stream from hydrogen sulfides without producing any unwanted compounds.

To make silver powder
Silver oxide acts as a catalyst in the preparation of silver powder. If heated above 280 degree C, silver oxide gets converted into silver powder, thereby releasing oxygen.

In silver oxide batteries
Silver oxide and zinc form the main constituents of a silver oxide battery (or silver –zinc battery). While silver oxide acts as the positive electrode (cathode), zinc behaves as the negative electrode (anode). Unlike its competitor counterparts, a silver oxide battery has higher durability, can handle higher current loads, inflammable and is free from thermal runaways. Such batteries are used in electronic devices and US military and Apollo space program.

As an antimicrobial agent
Silver oxide has enhanced antimicrobial properties and is often used in the manufacture of some infection-resistant surgical fabric materials as well as fibrous textile articles. It is also used for concrete and in some swimming pools and spas to protect the water from undesired microbes.


Friday, January 24, 2014

Uses of Laboratory Incubators

An incubator is equipment used in modern research laboratories for maintaining and regulating viable growth factors such as temperature, humidity and ventilation so that microbiological cultures can grow. Incubators are available in the market in varying sizes catering to different requirements- from tabletop to small room size. Some high-end incubators also have the capability to lower temperature (microbiological incubator) and control humidity or CO2 levels (CO2 incubator or cell culture incubator). The non-gassed incubator (microbiological) focuses mainly on the growth and storage of bacterial cultures and control temperature ranging from 5C to 70C. However, the gassed incubator (CO2 incubator) is generally used for cell cultures and provides a stable environment by maintaining temperature (37 C), relative humidity (95%) and CO2 for proper pH standards.

Uses of laboratory incubators
Laboratory incubators are widely involved in a number of applications such as cell and tissue culture, pharmaceutical studies, hematological studies, biochemical studies, food processing, cell aeration, plant and animal studies, solubility studies, fermentation studies and bacterial culturing.

Medical Treatments
For years, the controlled stable environment of the incubator was used for hatching poultry eggs and taking care of premature or sick babies. Today, incubators have more elaborative use and its market is thriving as a result of new applications. Scientists use incubators for medical treatments, stem cell research and experimental procedures like incubating antibodies on tissues and cells for fluorescence microscopy. They can also be used to diagnose the disease-causing pathogens in the human body. With the balanced and careful use of air around the cell culture, the microorganism multiplies and increases the probability of identifying the pathogen.

 Tissue culture
Incubators are now extensively used to study tissue cultures, that involves extracting tissue fragments from animals or plants, keeping these explants (isolation of cells from a piece or pieces of tissue) in an incubator and subsequently analyzing their growth. Study of these explants enables clinicians and scientists to understand the functioning of specific cells like cancer cells and help them in developing vaccines for diseases such as polio, mumps and measles. Also, these tissue cultures have helped scientists to detect various disorders resulting from the absence of certain enzymes.

Genetic engineering
New avenues have opened with the use of incubators in genetic engineering. Scientists have been able to use the explants from the tissue culture to manipulate their genetic material. It has also allowed them to form new organisms by combining DNAs from different sources. Genetic engineering has helped enhance the nutritional value of various fruits and vegetables and has also worked in increasing the disease-resistance level of many crops.

Thursday, January 23, 2014

Uses of Argon


Argon is an inert (or ‘noble’) gas, is listed in the periodic table as ‘Ar’, and was discovered in 1894 by Sir William Ramsay and Lord Rayleigh. Argon is manufactured by distilling the liquid air, and is one of the most abundant gases (third most abundant) in the earth’s atmosphere, and therefore inexpensive and environmentally friendly. It has multiple industrial and business uses.

Uses of Argon in Manufacturing Industry
Pure Argon, as well as when it is mixed with other gases, is used in “tungsten inert gas” welding purposes, as also in casting. Argon is also is used in the making of specialty alloys and for manufacturing titanium.

During manufacturing of steel in a converter, addition of argon reduces chromium losses and the desired carbon content can therefore be achieved at a lower temperature. Further, Argon is also used as a blowing gas during the manufacturing process of higher quality steels, so as to avoid the formation of nitrides.

Argon is used in the manufacturing of aluminum, for the purpose of hydrogen removal (and degasification in general), as well as other particulates. It is also used as an inert gas in the manufacturing of titanium manufacturing process, as titanium can react with nitrogen. Zirconium manufacture also uses argon for providing an inert atmosphere..

Uses of Argon in Healthcare Industry
Argon lasers find application in the treatment of retinal detachment as well as for retinal phototherapy for diabetics. Also, kidney tumors are treated using cryo-needles, as part of a procedure in cooled argon cryosurgery. Argon surgery is also used to treat heart arrhythmias.

Uses of Argon in Food and Beverages Industry
Argon also finds uses in food and beverages industry because of its inertness. It is added in wine barrels. Since, it is denser than air and settles above the liquid, thereby preventing its oxidation and souring of wine. Similarly, it is also used to provide an inert atmosphere for open wine and liquor bottles in bars and restaurants.

Uses of Argon in Lighting
Argon is used in neon tubes. When electricity is passed, it produces a purplish-blue glow. Since it gets charged and starts emitting light at a much lower voltage, it saves money and is therefore a preferred gas for this purpose. It has a similar application in fluorescent lighting as well.

Further, argon (or some other inert gas) is also used in light bulbs, as it prevents quick oxidation of the filament and therefore prolongs the life of the bulb.

Other Uses of Argon
Argon gas is used in superior quality thermal glass window panes. Given the inert nature of the gas, Argon is also used to give a protective atmosphere for old documents, so as to prevent their degradation during display and storage. Argon is also used (along with methane) to provide an inert atmosphere during manufacturing of silicone and germanium crystals for use in the semiconductor industry.

Wednesday, January 22, 2014

Uses of Aluminium wire

Aluminium wire (also spelled as aluminum wire), is largely used by domestic, commercial and industrial feeders. This type of wiring is relatively lighter, cheap and more flexible than its counterparts (including copper wire). However, aluminium wire can result in fire and therefore excessive care should be taken towards proper installation and termination methods and materials. A less cheap, but more effective alternative is the copper clad aluminium wire (abbreviated as CCAW or CCA). It is composed of inner core of aluminium and an outer covering of copper. CCAW is less hazardous than pure aluminium wire and weighs far less than the copper wire.

Uses of Aluminium wire
In construction industry
Aluminium is an excellent alternative to copper and is largely used in the manufacture of building wires. Electricians and contractors use large sizes of aluminium building wire where there is requirement of low voltage. This is more beneficial to contractors in terms of savings as it has half the weight of copper wire. Aluminium conductors for building wire are made in such a manner that the overall diameter of the aluminium wire is similar to that of copper wire.

In Electrical distribution industry
Utilities such as electrical distribution companies have been extensively using aluminum wire throughout their distributing systems (power grids) for transmission of electric current.

In communication industry
The copper clad aluminium wire is primarily used in high quality coils, power cables and antennas. The aluminium-copper combination finds its use in commercial as well as residential applications including household wiring, cable wiring, headphones, loudspeakers and antennas. CCAW are also used to help connect the internet to the computer. They are important components of cable modems and television connections as well as Ethernet connections (that is, LAN and WAN).

In broadcasting networks
Modern broadcasting networks (radio and television) largely rely on aluminium wire (CCAW) for information broadcast. Basically, two forms of radio networks are known- the first form is used for broadcasting and updates, advertising and marketing whereas the other form is the backbone of police and armed forces (used for communicating with each other). Television broadcasting involves transmitting signals through cable and satellite television.

In submarine communications
Aluminium wires clad with copper provide a great means of submarine communication and are installed below the floor of the ocean to expedite the process of information transfer across the globe.

In medical field
Aluminium wire finds also its use in medical science instruments that are involved in diagnostic processes such as medical ultrasonography.


Tuesday, January 21, 2014

Types of Ground Penetrating Radars


Radar (abbreviation for ‘Radio Detection and Ranging’) is an electronic instrument that detects mobile and stationery objects by measuring their speed, direction and altitude. Radars are used for a variety of purposes such as air traffic control, speeding traffic and meteorological measurements. Further, a system that images the sub-surface in a non-destructive and non-intrusive manner is known as the ground penetrating radar. It can measure and map a variety of terrain (such as rocks, soil, water, ice, and man made constructions) and is used in different applications (such as archeological surveys, natural resource exploration, civil engineering, forensic investigations, environmental remediation and three dimensional topography imaging).

Types of Ground Penetrating Radars
Ground penetrating radars consist of an emitter of high frequency waves in the microwave UHF or VHF band, and a receiver that detects and amplifies the scattered and reflected waves. Ground penetrating radars can be of various types; differing primarily in data collection techniques used (i.e.; whether it is in the time or frequency domain). These can therefore be broadly classified on the basis of whether they deploy impulse (called impulse radar; operating in the time domain) or continuous waves (called continuous wave radar; operating in the frequency domain), and variations thereof.

Impulse (Ground Penetrating) Radars
Impulse radars acquire data on the reflected energy as a function of time. Since impulse radar has low cost parts and deploys simple impulse waveform generating, it is commercially very powerful. It however has one major disadvantage in that the resolution of its imaging is restricted by the width of the pulse that is used.

Continuous Wave (Ground Penetrating) Radars
Continuous wave radars acquire and continuously transmit data on the reflected energy as a function of frequency. Technique involved is to transmit a frequency sweep over a fixed bandwidth, i.e. from a beginning to an end frequency. Reflections waves are mapped as a function of frequency and are a measure of the energy that has been scattered from subsurface objects.

Stepped Frequency (Ground Penetrating) Radars
Another variation is the stepped frequency radar, which transmits data on reflected energy in stepped linear increments over fixed bandwidths. To eliminate the issue of weaker signals from deeper targets getting masked by the stronger signals, compensation is made for lateral scattering and by taking cognizance of the unambiguous range that can be most accurately measured by the stepped frequency radar.

Other Types of Ground Penetrating Radars
Further variations of the above types of ground penetration radars are ultra wide band radars, synthetic aperture radars, noise source radars and arbitrary waveform radars. Some custom ground penetration radars may also be designed, such as borehole radars.

Monday, January 20, 2014

Tools used for removing topsoil

Topsoil is a highly productive, uppermost layer of the earth’s crust and is nearly 20 centimeters deep. It is vital for plant growth and takes thousands of years to form naturally.  Rich in nutrients and moisture, topsoil serves as a very fertile medium for viable growth of plants and trees. Topsoil removal from the agricultural fields and landscapes can lead to irreversible depression of the land fertility. Removal of the topsoil can also result in nutrient imbalance, increasing the probability of leaching and soil erosion.
Modern farming practices promote crop rotation (alternating nitrogen-fixing plants for better crop yield) to conserve the valuable topsoil. Farmers who do not follow healthy practices are destroying the top layer and the results can be quite disastrous. Biologists are concerned because if the topsoil gets damaged or degrades, more complex methods will be required to restore the nutritional balance of the soil.

Tools used for removing topsoil
Trowel
A trowel is a versatile pointed tool with a metal scoop-shaped blade and a handle for digging and carrying soil. It is used for planting and weeding plants. Different kinds of trowels are available in the market for different purposes. Pointed trowel works well with hard, toughened soil. Wide blades help move the soil fast, whereas a narrow blade trowel is ideal for digging small holes.  Some trowels come with a depth measuring gauge to help the user know the exact depth while digging. A good quality trowel is light weight and has a carbon steel blade for better performance.

Rake
A rake is a cultivating tool used to remove the top soil. Rakes groom the soil for plantation and growth of the plants. There are two main types of rakes for this purpose- bowhead rake and flathead rake.
Bowhead rakes has a teethed-wide head that is used for filtering and removing unwanted waste and debris from the soil. On the other hand, flathead rakes are useful in smoothening and preparing the soil for sowing. Top-notch rakes are made from a single piece of high-carbon steel and the teeth of the rake are then inserted into the steel. This makes for easy repair of the rake if the tooth gets loose.

Shovel
The word shovel derives its name from the old English word “scofan” meaning “to thrust away”. An indispensable tool, shovel is used for digging, lifting and throwing of the soil. The shovel consists of the slight scoop-shaped blade and a long handle. The blade is set at an angle for sturdy grip and forceful lift of the soil. The most popular kind of shovel that is normally used for all kinds of digging is the round- point shovel. It is ideal for breaking through the hardest surface because all the force applied gets concentrated at a single point.
A heavy shovel is more suitable and effective than their lighter counterparts. Although less tiring and easy to use, a light-weight shovel is fragile, tends to break easily and is less durable.

Friday, January 17, 2014

Types of Thermocouple Wires

Thermocouples are metal junctions made of alloys with high heat and electrical conductivity, which determine temperatures by measuring heat induced electric voltage gradients. They find application wherever ambient temperature based automatic cutoffs and activations are required (such as in heaters or heat alarms). Thermocouples can be used to measure and control over a wide temperature range and as they are relatively cheap, they are popular in a variety of industrial and household applications but are generally used as thermopiles (multiple thermocouples connected in series or parallel). One drawback is that thermocouples are not very accurate for measuring differentials of less than 1K, although this can be partially compensated through instrumentation.

Types of Thermocouple Wires
Thermocouples vary by the metal alloy used in manufacturing, which determines their physical properties such as conductivity, magnetism and the temperature range that they can measure. They may also be classified based on the insulation type.

Standard Thermocouple Types
Type K is a general purpose thermocouple, and is made with chromel-alumel. It is inexpensive and has a wide temperature range from -200C to 1350C. It also has nickel, which makes it magnetic. Type E is a chromel-constantan non-magnetic thermocouple wire most suitable for cryogenic use. It can measure over a temperature range of -40C to 900C. Type J is made with iron-constantan. Although it has a relatively restricted temperature range (-40C to 750C) because of the presence of iron, it has a higher sensitivity. Type N thermocouple wire is a nicrosil-nisil alloy, and is most effective in measuring temperature ranges over 1200C. The composition also makes it less susceptible to high temperature oxidation. 

Low Sensitivity Thermocouple Wires
Low sensitivity thermocouple wires are made of platinum-rhodium alloy. Although having relatively low sensitivity, these are the most stable thermocouple materials available. Presence of platinum also makes them expensive and these are therefore only used in specialized situations such as measuring very high temperatures.

Type B is a platinum-rhodium thermocouple that can measure temperatures from 0C to 1800C. Type R and S are also made from platinum-rhodium (with varying percentage of rhodium), and measures temperatures up to 1600C.

Thermocouple wires of other alloys
Type T is a non-magnetic thermocouple made of copper-constantum and can measure temperature in the range of -200C to 350C. Type C thermocouple is made of tungsten and rhenium, with a very wide range of 0C to 2300C. Care should however be taken to not use it in the presence of oxygen and at temperatures above 260C, and are infact most suited for use in vacuum furnaces. Nickel is used in Type N thermocouples and can measure temperatures up to 1400C.

Thermocouple wires by insulation type
Metal sheathed thermocouple wires have magnesium oxide insulation and are covered with a metal sheath. Duplex insulated wires, which is the most common type, has a simple insulation that can vary by the application. Finally, a bare thermocouple wire however has no insulation.


Thursday, January 16, 2014

Stone Walls


Stone has been used as a primary material in the construction of buildings, barricades and fortifications for a long time, and can therefore be seen in a variety of civic structures that we have around us – with some of them even dating back to ancient civilizations.
More recently however, stone has also found new applications within construction works. While it still serves the traditional purpose of providing strength to the structure as well as protecting the interiors from unwanted elements – both natural and otherwise, it is now also used in landscaping of living spaces, as well as in flooring and walls.
Examples of Stone Walls
A wide variety of stone walls can be constructed, primarily differing by the stone material, its finish or the intended purpose it serves, as also the type of construction.
Stone Walls by Material Type
Large stone walls are masonry constructions usually made of locally available (though not always!) stones such as flint, granite, sandstone, limestone or marble, etc. The primary purpose of using stone in the construction of walls with such hard and non-absorbing material is to prevent weathering and erosion or to provide strength and stability to the structure.
Stone Walls by Construction Type
Block stone walls are free-standing and are generally exterior facing. Such walls will typically have both seam and split faces. To further give it a unique and individualized personality, it can also be used with a combination of various naturally occurring stone products.
Alternatively, uniformly rising stone walls are constructed with a lesser height variation, run for shorter lengths and are in general smaller and easier to construct and maintain.
On the other hand, a thin stone wall is generally 1 to 3 inches in thickness (and is definitely less deep than the heavier stone walls discussed above). Such thin stone walls are increasingly becoming common, given the recent trend of using stones to provide an aesthetic appeal to construction or in landscaping.
Smaller stone walls may also be constructed as garden bed edgings. The intended use of this product is to provide a curbing for bordering driveways and walkways, in lawns and gardens, and to give a clean-cut and well-defined look. It may also be used to encircle trees and to prevent soil erosion.
Stone Walls by Finish
Stone walls can also be typically named after their shape and finish. Based on this definition, there can be three principal categorizations – rubble walls, squared rubble walls, and ashlar stone walls (or walls made of large dressed cubical blocks of stones), although each of these can have further several sub-classifications based on certain subtle differences. The imperviousness and strength of these rubble walls will vary based on the quality of mortar used to bind them.

Wednesday, January 15, 2014

Side effects of Magnesium stearate


Side-effects of Magnesium Stearate consumption
Magnesium Stearate, which is also known as Stearic Acid, is a metal derivative. It is not required by the body and is actually toxic in nature. However, it is generally still used in the manufacturing of dietary supplements, as it is a FDA specified granulating and formulating agent. While these supplements can be prepared even without the addition of the Magnesium Stearate agent, the process takes more time, is liable to caking the salt, and also mandates very specific and meticulous precautions during preparation. Therefore, magnesium stearate is added during the process, to increase the production rate. But it sometimes gets concentrated in very high amounts during the manufacturing of these pills. A related issue is also the source from which magnesium stearate is isolated – common sources being palm oil and hydrogenated cottonseed oil (used for lubricating the machinery used in manufacturing of these dietary supplements) and these may produce toxic products that may contain hazardous pesticides.

Health issues caused by Magnesium Stearate
Magnesium stearate, if it is consumed in small dosages, does not have any serious health related side-effects. It can however have an adverse impact on an individual’s health, if it is taken in higher doses (due to the consumption of dietary pills that contain magnesium stearate).

Effect of Magnesium Stearate in Absorption of Nutrients
Excessive magnesium stearate can lead to a decrease in the absorption level of nutrients. Tablets without magnesium stearate have a very high absorption rate (as much as 90 percent), but can drop to levels below 25-30 percent for ones that have it.

Effect of Magnesium Stearate on the Immune System
Since magnesium stearate is an immuno-suppressor, its excess dosage can also have a negative impact on T-cell functioning, which can adversely affect the immune system of the body. Therefore, continued usage can significantly weaken the immune system as well.

Gastroenteritis due to Magnesium Stearate
Excess consumption of magnesium stearate can also cause gastroenteritis, or inflammation of the stomach and the intestines.

Respiratory problems due to Magnesium Stearate
Further, magnesium stearate powder and fumes, if inhaled, can also cause an inflammation of the respiratory system and even asphyxia, and can be particularly impacting those people who are allergic or hypersensitive.

Ophthalmic problems caused by Magnesium Stearate
Magnesium stearate has also been reported to cause dryness in the eyes. It has been argued that since magnesium stearate is used in capsules to prevent them from caking by absorbing moisture, this when consumed has the same effect on the eyes. There is however no conclusive medical evidence to support this diagnosis.

Tuesday, January 14, 2014

Side effects of Hibiclens chlorhexidine gluconate

Hibiclens is an over-the-counter brand name for the antiseptic and bacteriostatic chemical called chlorhexidine gluconate. It is a skin cleanser and is bactericidal in action to both the gram positive as well as the gram negative bacteria. This medicine can kill the bacteria by attaching itself to the surface of the microbial cell and then destroying the cell membrane. Generally marketed as a skin cleanser, hibiclens chlorhexidine gluconate is mainly used both as a hand antiseptic as well as for washing of wounds. It is also often used topically as a pre-operative skin preparation and is available as acne skin wash. Instead of iodine, hibiclens is used as a rubbing agent to clean the area on the skin prior to the use of hypodermic or intravenous needles. It is also an effective disinfectant around the blood collection and urinary catheter sites, as it can help in prevention the growth of bacteria when applied on burns. However, like any other drug, hibiclens also has certain side effects.

Side effects of Hibiclens chlorhexidine gluconate

Common effects
Application of Hibiclens chlorhexidine gluconate should be limited only to wounds involving damage of superficial layers of skin. Pregnant women or lactating mothers should however always consult the doctor before using this medicine. Although there are no reports to prove the presence of chlorhexidine in lactating milk, it is still advisable to thoroughly wash the breasts before nursing, if the drug has been used on the breasts for cleansing the skin. 

Hypersensitivity and allergic reactions
Hibiclens chlorhexidine gluconate can be quite harmful in higher concentrations as it can pose serious allergic reactions and skin irritation. It can be life-threatening and should be avoided or atleast carefully administered by people who have a high sensitivity to this drug. Allergic symptoms can occur if the drug comes in contact with the mucous membrane of any part of the body (that is, membranes of the anus, genitals or mouth). It can also lower the blood pressure, increase heart rate, and can cause blistering, burning, skin rashes, itchiness, peeling and other signs of irritation such as redness or swelling of the skin, mouth, tongue, face and lips, hives, shortness of breath and tightness of chest.

Ocular effects
Hibiclens should always be kept away from eyes (as it can cause corneal damage), ears and mouth and should strictly be used externally. Accidental exposure of the chlorhexidine cleanser to eyes during the pre-preparation of facial surgery can sometimes result in severe eye pain, inflammation of the conjunctiva and swelling of the epithelium, keratitis, corneal epithelial cell loss and chronic corneal ulcers.

Monday, January 13, 2014

Side effects of Camphor in skin products

Camphor is an active ingredient in many medications and skin products, while also being a well established folk remedy. It has a characteristic pleasant smell and is commonly used to treat problems associated with breathing and sinus as well as those related to poor blood circulation and pain in the joints. Camphor is also used as a rubefacient when applied on the skin and it causes a cooling effect. When applied to skin, it acts by stimulating the nerve endings for relieving the pain and itching, while the irritation that it can cause on the skin can also block the pain by a counter-irritation at the nervous system level. Camphor has local anesthetic effects as well. Topical use of camphor can even treat respiratory tract and heart disease symptoms and is also used for treatment of fungal infections of toenail and warts.

Side effects of Camphor in skin products
Exposure to camphor, whether by absorption through skin or by oral consumption, can however have serious health implications such as respiratory problems, chest pain, skin irritation and rashes and even be fatal in certain situations. But it is generally safe when absorbed through the application of creams and lotions on the skin or when inhaled, as it is present here in small amounts. Undiluted or concentrated camphor products should however be strictly avoided as it can cause toxicity and irritation. Also, camphor containing products should never be heated or micro-waved, as this is likely to cause an explosion and lead to severe burns.

Camphor toxicity
Camphor can easily penetrate through the skin, the placental barrier and the mucous membrane, and this may lead to a serious condition of hepatotoxicity. Laboratory tests also indicate that a generalized damage of the body tissue can occur due to camphor exposure and toxicity.

Side-effects on children
Further, even small doses of camphor exposure in children can have serious health implications and can also cause death in small, malnourished infants.

Even though the relatively lower concentration of camphor in cold medications such as Vicks Vaporub is not toxic enough and a very large exposure is needed to cause any health problems. The implication of using such medication on children is still debatable though, and even if these are not recommended for infants below 2 years, most parents are totally unaware of the possible issues with camphor toxicity and nevertheless use it on children as a cold remedy.

Application on broken skin
Particular care should be taken to not apply camphor (or any product having significant of camphor concentration) to broken skin, as this will accelerate the process of body absorption and therefore much easily cause camphor toxicity related health problems.

Side-effects on Pregnancy
Health effects of camphor application on the skin of pregnant women or at the time of breast-feeding are not known, although oral consumption can definitely be unsafe for both the mother and the baby. It is therefore recommended that camphor containing products in any form should be avoided during this period.


Friday, January 10, 2014

Responsibilities of a Salesperson

Sales representative are pivotal in the growth and success of their individual organizations. The duties and responsibilities of sales professional may vary from one sector to the other. Their core job, regardless of the industry, is to promote the product or service they are selling, develop interest in the customers for their company service or merchandise and understand the queries and concerns of the client. A good salesperson must be focused and persistent. They must be communicative; should be able to target the needs and requirements of the buyer; address them; answer all the concerns and doubts and then finally close the deal.

The primary duty of a sales representative is to look out for potential customers. He should be keen to develop good communication relationship with the client and try to understand the needs of the prospect.

One of the valuable attributes of a salesperson is to qualify his prospect. It is a crucial step for starting any business with the client.  Ability to beautifully present the service or product is a must-have skill for sales professional. It is very important for him to know and understand the product, or if high technical sales are involved, should be able to bring along the technical expert with him while he presents the business to the customer. This is a very smart tactic and works well in such situations. A great salesperson should address all the aspects of the business and must make it sound approachable to the client. If he misses on this front, his presentation will lack the effect and he may lose the prospective customer. However, if the buyer shows the interest by asking questions and seeks clarifications, the salesperson has hit the interest bang on target.

A friendly, personal approach to the customer is a great way to persuade him to develop interest in the business. It might sound easier but it is a lot more complicated. Actively listening to the customer and his needs, and if needed, persuading him to ask questions, is a must-have quality that is required in a salesperson.

The most important step is facing all the objections and closing the deal. To be able to finalize the sale and help the client in each and every possible way is an integral part of a good salesmanship. He should be polite, tactful and persistent throughout the presentation. A sales representative should courteously deal with all the objections and queries in the end and leave a long-lasting impact on the client.

Thursday, January 9, 2014

Requirements of Hazardous Waste Area

Today, our environment is facing the biggest and most unnoticed threat in the form of hazardous waste that is disposed off by humans into the atmosphere. Often, this waste poses substantial or potential damage to both nature as well as human life. Hazardous waste may be flammable, toxic, reactive or corrosive. It may be in the form of solids, liquids or vapor and are not disposable by common means. The physical state of the waste material will decide if it can be broken down or decomposed by the use of various treatment and solidification procedures. Common man awareness is important to reduce environmental pollution caused by these hazardous materials.

Requirements of hazardous waste landfill
A hazardous waste area is the allotted area or part of the land which can be safely used for the accumulation and accommodation of waste containers and their contents for the required amount of waste accumulation period. The landfill may be a land, a surface impoundment, a salt dome formation, an underground mine, cave or an underground injection well.

Landfill control
A hazardous waste accumulation area must have a run-on control system (hold the flow onto the active side of the area during peak discharge of 25 yr storm), a run-off management system (collect and control the flow of water from a 25 yr storm), and control the dispersal of particulate matter by wind. The tanks or containers for collecting the contents of run-on and run-off systems should be emptied after passing of the storms.

Documentation and labeling
Each landfill should have a guiding map with exact location markings and specifications, including the dimensions of cells in comparison to permanently surveyed standards.

Also, all the hazardous waste containers should be labeled “hazardous waste” (with the chemical name of the waste, its classification and the date) at the time when the waste is first added to the container.

Closure
While designing and constructing the final cover of the hazardous landfill, following points should be considered-
  • minimal migration of liquids from the closed waste area
  • minimum maintenance requirement
  • promoting drainage and preventing erosion or damage of the cover
  • maintaining the balance of the cover by tolerating settling
  • permeability should be kept lower than that of the bottom liner system
Postclosure
The balance between the integrity and the effectiveness of the final cover should be maintained which may also include making changes to the cover as required (to maintain the effects of erosion, settling and subsidence). Postclosure involves thorough checking of all leak detection and groundwater maintaining systems and may normally last for at least 30 years after closure.

Safety
Proper care should be administered while handling hazardous waste materials. Safety requirements include an applicable emergency information and equipment such as-
  • Emergency equipments like shower and eyewash
  • Warning and directional information regarding the nearest telephone, exit or signs for emergency equipment
  • Signage that indicate area and contact information

Wednesday, January 8, 2014

Recycling Regulations

Recycling is the process of reusing materials that are potentially useful, once they have been refurbished or salvaged from waste and discarded material. This is primarily done not only for economical reasons but to also save the ever depleting raw materials and natural resources, be more energy efficient, reduce pollution and carbon footprint and to also ensure that toxic, hazardous and expensive materials are extracted and appropriately consumed or disposed. Many different types of materials can be recycled – such as paper, metal, glass, plastic, textile and electronics. Typically, materials that are to be recycled are collected from household and industrial waste and then brought to a recycling center, where they are sorted, cleaned and reprocessed to produce the recycled material.

Recycling Regulations
For a recycling initiative to be successful as well as financially viable, it has to be ensured that a large and stable supply of recycling material is made available to it for a long time. Legislation has played an important role in this, by implementing laws that make collection of recyclable material mandatory, through ‘container deposit legislation’ and bans of refuse.

The Role of EPA in Recycling Regulations
The United States Environmental Protection Agency (also referred to as the EPA), is the federal agency responsible for all matters related to waste material disposal, treatment and recycling; while also ensuring that the environment is protected. The EPA therefore formulates regulations pertaining to recycling, treatment of hazardous wastes, landfill regulations, as well as for setting recycling targets. While the EPA is responsible for the above at a national level, recycling legislation is also localized at a state or city level.

Ban on Landfills
Certain states in the US (namely North Carolina, Michigan, Minnesota and Wisconsin) have put a ban on landfills, thereby making it illegal to dispose of certain items (such as yard waste, oil, etc.) without recycling. Further, the National Computer Recycling Act makes it illegal to dispose of CRTs in landfills. Not only dumping in landfills is a waste of precious recyclable material, it may also lead to contamination of ground water with hazardous materials and toxins.

Container Deposit Legislation
Many US states (namely California, Connecticut, Delaware, Hawaii, Iowa, Maine, Massachusetts, Michigan, New York, Oregon and Vermont) have a legislation that mandates the collection of a deposit whenever liquids such as carbonated drinks, milk, water or alcohol are sold in recyclable bottles and containers. However, this deposit is totally or partially refunded when these are returned in designated collection centers, which then aggregate all the recyclable material and send it onwards to recycling plants. The deposit is generally about five cents (with the highest being 10 cents in Michigan).

Other Regulations
Some states (such as California and Illinois) have recycling targets. Cities like New York City and Seattle have laws that penalize citizens for throwing away recyclable materials. Additionally, governments also give incentives for running voluntary programs that encourage and educate people with the benefits of recycling.

Tuesday, January 7, 2014

Properties of Bearing Steel


Bearings are important mechanical components that find their primary application in continuously moving machine parts which may get subjected to high fatigue and stress conditions. These bearings facilitate in effectively transmitting dynamic loads within the machine body, as well as help in reducing friction between the moving parts, thereby ensuring a smooth motion. These could be of various types (such as ball bearings and tapered, cylindrical or needle roller bearings) and are manufactured using a grade of steel that has mechanical properties which are more suited for lowering the friction levels (compared to the other available carbon steel grades). Manufacturing of bearing steel requires melting the metal and degassing it, followed by certain metallurgical processes, and then tempering and quenching, with finally grinding or polishing the alloy.

Chemical Composition of Bearing Steel
Bearing steel has carbon content in the range of 0.55 to 1.10 %, manganese in the range of 0.10 to 1.15 %, silicon in the range of 0.15 to 2.0 %, phosphorus and sulphur up to a maximum of 0.03 %, chromium in the range of 0.5 to 2.0 %, as well as traces of titanium. The remaining % is iron.

Chemical properties determine the anti-corrosive properties of the alloy. The chemical composition of the steel also dictates its mechanical and physical properties (such as the strength and hardness, toughness and brittleness, ductility and malleability).

Mechanical Properties of Bearing Steel
Bearing steel has a bending strength of 2400 MPa, and can withstand high stress and centrifugal forces, although it has a low corrosion resistance.

Bearings materials can either be through-hardened or case-hardened, and may also require vacuum-processing to ensure purity. A minimum expected hardness for bearing components is 58 Rc, but bearing steel has generally higher hardness levels.

Carbon increases the strength of bearing steel, which ensures that parts made from it do not deform on the application of stress and load, while also increasing its hardness. Ductility and weldability however decrease with increasing carbon content, as is the case with bearing steel.

Bearing steel is designed to have high fatigue strength and life, needs to respond uniformly to the heat treatment process, and should have a compact structure with a consistent grain flow and a fine grain size that imparts high impact toughness to the alloy.

Physical Properties of Bearing Steel
Bearing steel has a density of 7.85 gm/cubic-cm, coefficient of linear expansion of 0.00001 /K, thermal conductivity of 30-40 W mK and is magnetic and a good thermal and electrical conductor.


Monday, January 6, 2014

Popular careers and what they pay

With the changing situations of the economic and employment market everyday, there has been quite a dramatic effect on the job sectors. Technological development, one of the main reasons for affecting almost each and every area of our society, has opened new avenues and opportunities. Certain factors can change the job market dimensions and increase common interest in certain areas- like TV shows or media coverage.
Some areas of employment that are predicted to rise faster than other careers over the next few years are-
Network Systems Analysts
The main focus of systems analysts is to solve problems related to networked computer technology. The growth of IT sector has given rise to the increase in organizations requiring the installation and maintenance of networked communications. Analysts test, design, and analyze different networks like LAN, internet, intranet and other data communications systems.
A Network Systems Analyst must be a logical thinker and a good communicator. The expected salary for a typical Systems Analyst in US is approximately $38,931.
Physician’s Assistant
A physician assistant (PA) is a trained healthcare professional, with a qualification of academic and clinical skills to provide diagnostic, therapeutic and preventative healthcare services under the guidance of a specialist.
PAs are vital as they undertake all matters of a patient and work in different departments of the hospital. The expected salary for a Physician Assistant in US is $82,319
Medical Assistants
Development in the healthcare sector has led to the rise in administrative and clinical tasks that need to be focused. Medical assistants help physicians performing these functions. They typically work in hospitals, clinics or doctor’s office. Their strata of work may range from working on patients and in laboratory to bookkeeping and receiving calls.
The median appropriate salary is United States is around $24,610 per year.
Fitness Trainers
A fitness trainer is a skilled, certified instructor who trains and leads a single client (personalized trainer) or a group of individuals in a range of physical activities. They may work privately, or be employed at a gym, club, hospitals or in yoga classes.
The core responsibility of a fitness trainer is to motivate people, instigate and inspire them the benefits of health and muscle building. A qualified trainer must be a good listener and a great communicator and motivator. He should be strong and have a good physical and mental health. The total annual compensation of a fitness trainer in US is expected to be approximately $52,535
Physical Therapist Aide
Typically, a physical therapist aide works under the supervision of a physical therapist and a physical therapist assistant. They enhance the productivity of therapeutic sessions by maintaining cleanliness in and around the treatment areas; getting the area ready for the patient by organizing and preparing them for the sessions and helping the patients get in and out of these treatment areas.
A physical therapist aide gets trained while working on the job after getting a basic high school diploma qualification. They earn a median salary of around $22,060 in US.

Friday, January 3, 2014

Organic chemistry jobs

Organic chemistry is the study or the discipline of chemistry that explores the various properties and reactions of carbon-containing compounds. It has become vital for our day-to-day needs and is expanding its approach in industries such as rubber, dye, detergent, cosmetics and agriculture. The vast knowledge of organic chemistry has opened new pathways for students who find an aptitude for these complex compounds and has become central to various career avenues.

Careers in Organic chemistry
Organic chemist
An organic chemist is critical in all those areas where there is dependency on the research and development. They study organic compounds, their physical and chemical properties and the chain of reactions that produce them. With this knowledge, they explore new uses of these compounds or try to find new organic materials. Also, organic chemists analyze and understand each and every aspect of the compounds and use them for making medicines that can treat life-threatening diseases. Normally, a pharmaceutical researcher has a doctorate degree and earns an average annual pay of $86,421.

Forensic Scientist
Organic chemistry is involved in all the fields of science that are applied to life-this includes the field of forensic science. It is used by scientists to investigate and test samples of blood or saliva collected at the scene of crime. Various tools and testing solutions may also be used to analyze physical materials like hair and carpet, as well as carpet fibers. Forensic scientist may be a medical doctor or a chemist and earn an hourly median salary of around $21.79

Pharmacist
The primary job of a pharmacist is to distribute medicines at the prescription of a certified doctor. They can also suggest patients, physicians and health practitioners about the dosage and side effects of drugs. Some pharmacists are also certified to administer medicines. They may work in a private pharmacy, a hospital or a nursing care facility. A pharmacist is required to get a specialized degree as well as a license to follow his practice, and should also know drug law in some states. The average annual salary of a pharmacist is nearly $106,410.

Medical doctor and biotechnologist
The fields of medicine and biotechnology are interdisciplinary. Organic chemistry plays an important role in the study and manipulation of DNA and requires a lot of research. Biotechnologists work on agricultural products, as well as with plants and animals. Normally, a biotechnologist has a masters degree in the field and usually also involve medical doctors. The median salary of a biotechnology research scientist in USA is around $63,000.

Professor of chemistry
Although, the main job of a chemistry professor is to teach students, but at times, the actual job may also require conducting research in their chosen field. Also, chemistry professors are expected to run the department, act as an interface for the university and may also participate in other college activities. The desired qualification for a professor is a master or a doctorate degree in accredited colleges and universities. They earn an average annual salary of $74,655.