Chemistry in Ink

An ink is a liquid containing various pigments and dyes used for coloring a surface to produce an image, text or design. Ink is used for drawing and writing with a pen, brush or quiill. Ink is a complex medium composed of solvents, pigments, dyes, resins, lubricants, solubilizers, surfactants, particulate matter, flourescsers.


Dye-based inks are generally much stronger than pigment-based inks and can produce much more color of a given dentsity per unit of mass. However, because dyes are dissolved in the liquid phase, they have a tendency to soak into paper.


Cellulose, the material that paper is made of, is naturally charged, and so a compound that complexes with both the dye and the paper's surface will aid retention at the surface. Such compound in common use in ink-jet printing inks is polyvinyl pyrrolidone.


An additional advantage of dye-based ink systems is that the dye molecules interact chemically with other ink ingredients. Because dyes get their color from the interaction of electrons in their molecules, the way in which the electrons can move is determined by the charge and extent of electron delocalization in the other ink ingredients. The color emerges as a function of the light energy that falls on the dye.





References

~"A History of Technology and Invention", by Maurice Audin
~Martin-Gil J, Ramos-Sanchez MC " Chemical composition of a fountain pen ink", Journal of Chemical Education

Sweating

Sweating is also known as perspiration, transpiration or even diaphoresis. It is secreted by the sweat gland under the skin of the mammals. It mostly consists of water and dissolved substances. Sweat contains various kinds of chemicals such as odorants(2-methylphenol and 4-methylphenol) as well as little amount of urea. The purpose of sweating is mainly to regulate the body temperature or thermoregulation. Sweating can achieve the goal of regulating the body temperature by evaporation from the skin surfaces because it has a cooling result due to the latent heat of evaporation of water. If a body move rapidly or doing exercises, sweating will be promoted due to the increase of metabolic rate and vice versa. The volume of water lost in sweat daily is highly variable, ranging from 100 to 8,000 mL/day. Sweat mainly contains of water and also minerals(like sodium, calcium, magnesium,and potassium) or even urea. Also many kinds of trace elements excreted along in the sweat such as iron, chromium, nickle and lead. The different circumstances of the internal environment will vary different composition of the sweat.

Sweating can be embarrassing, mostly because of the odor or smell came along with it, and nobody like to move around with wet clothes. However sweating should be nothing to get embarrassed about it. Usually men sweat more than women and most people would like to never sweat again. They willing to spend their money to buying up various kinds of antiperspirants, deodorants or body sprays. In fact, these should be avoided at all cost because these articles can block the pores in the skin sweat can causing cannot release the harmful toxins. Most of the deodorants contain aluminum which can makes its way into our bloodstream and eventually causing many diseases. Sweating should never be stopped because it helps to eliminate harmful toxins from the body and cleans the pores in the skin, thus helping to reduce black heads and acne. One of the advantages is that mentioned just now it can control the body temperature in hot situation and while exercising; thus it prevents one from having a heat stroke. It also prevents individual from toxins or chemicals by diluting them with sweat as they come in to contact with the skin. Some of the scientists found that sweating has smell that acts as scent. This scent sends secret signals to people around an individual. It is usually used for attracting your loved ones. Finally, sweat contains a natural antibiotic called dermicidin that helps to destroy bacteria on the skin.

But as everything has pros and cons, as well as sweating, over sweating is considered troublesome by many as it is clearly visible and obvious on the clothes and face. Besides, sweating caused bad odor, thus many people around you dislike it and they might move away from you. Sweating especially on hands makes it difficult to grab things and this might bring suffer also.







References:
Mosher HH (1933). "Simultaneous Study of Constituents of Urine and Perspiration". The Journal of Biological Chemistry 99: 781–790. http://www.jbc.org/cgi/reprint/99/3/781.pdf.

Chemistry of Cosmetics

The use of cosmetics is not a thing of the future. In fact, cosmetics were founded in Ancient Egyptian time. It was said that Ancient Egyptian women used kohl to darken their eyelids, and Cleopatra said to have bathed in milk to whiten and soften her skin. Not only that, Greek women used poisonous lead carbonate to achieve a pale looking complexion, and in the end claiming the life of the wearer due to its poisonous state. Today, cosmetics are big business. Cosmetic advertising are everywhere, attracting males and females who seriously cares about appearances.


What is a cosmetic? Cosmetic is defined as a substance or preparation intended for placemtn in contact with any external part of the human body. Cosmetics are used to cleanse, perfume, protect and change the appearance of the body or to alter its odours. Products that claim to modify bodily process or prevent diagnose, cure or alleviate any disease, ailment or defects are called therapeutics. This means that shampoos and deodorants are placed in the cosmetics category, while anti-dandruff shampoos and antiperspirants are considered therapeutics.

What do cosmetics contain? Most cosmetics contain water, emulsifier, preservative, thickener, colour, fragrance and pH stabilisers. For emulsifiers, emulsifiers are small droplets of oil dispersed in water or small droplets of water dispersed in oil.
Emulsifiers work by changing the surface tension between water and the oil, thus producing a homogeneous product with an even texture. As for preservatives, preservatives are added to prevent the growth of microoganisms, which can spoil the product and most probably harm the user. Preservatives used in cosmetics include parabens, benzyl alcohol and tetrasodium EDTA( ethylenediaminetetra-acetic acid).

Thickening agents such as polymers are often added to change the cosmetics consistency. Polymers can be synthetic (polyetylene glycol) or derived from natural sources (polysaccharides). Seaweed are common source of polysaccharides. Cosmetics that are too thick can be diluted with solvents such as water or alcohol.


Unfortunately, sometimes the ingredients in cosmetics can have unintended side-effects. For example, skin allergies to specific ingredients can be a problem. Allergies to cosmetic products can be due to chemicals such as added fragrances and preservatives. This can lead to skin rash where the product is applied. Chemicals causing the allergy can be avoided by reading product labels. Other people, which is not allergic to a specific ingredient, may nevertheless find the product irritates their skin becuase it damages the otuer layers, knwon as irritant dermatitis


Exfoliants and skin peels leave skin underneath temporarily more vulnerable to sun exprosure because they remove the outermost protective layer of dead skin cells. Excessive use of make-up or oily moisturiser can block pores and aggravate acne. More serious side effects are breast cancer with deodorants. Parabens, a class of chemicals commonly used as preservatives in deodorants and antiperspirants.

In the pursuit of beauty, there lies side effects. Therefore, it is wise to remember that cosmetics can be complex combinations of chemicals. Reading and understanding which ingredients are used in product are helpful when putting on cosmetics.




Referrence links,

http://www.science.org.au/nova/083/083key.htm

http://en.wikipedia.org/wiki/Cosmetics

http://www.badscience.net/category/cosmetics/

bad air breathed daily

Nowadays, seeing cars is as normal as seeing grasses and clouds. cars are the most basic transport for human especially city peoples. try to imagine if this world with no car exists, people will still be sitting horse cars, ox cars, rickshaws, dog sleds...and even pedal cars... i believe engine will be invented no matter what due to these inconveniences. well, what do modern cars really emits in our daily life? a point of fact, modern cars have two totally different personalities. one is friendly and attractive, the other one is destructive and lethal. how are cars so destructive? basically, gases produced by cars and emitted through car exhaust are poisonous and as mentioned, destructive. for instances, hydrocarbons, carbon monoxide, nitrogen oxide, particulates and sulphur dioxide.

Initially, hydrocarbons like unburned or half-burned fuel are a major contributor to urban smoke. It is toxic and will cause liver damage and even worst, cancer. Besides, hydrocarbons like methane, is also one of the greenhouse gases. It's environmental unfriendly and unhealthy for people as well. Secondly is the well-known gas which is carbon monoxide. Carbon monoxide is also a product of incomplete combustion. Inhaling carbon monoxide will cause the reduction to the ability of blood to carry oxygen. It will compete with oxygen to bind with a air transport mechanism in blood called haemoglobin. Overexposure may be fatal.

Besides that, when nitrogen in the air reacts with oxygen is a high temperature and pressure inside the engine, nitrogen oxides will be generated. It is a precursor to smog and acid rain. Nitrogen oxides will also destroy the resistance to respiratory infection. Especially delivery trucks, hot exhaust they blew containing life threatening amount of nitrogen oxides into the atmosphere. Particulate like soot or smoke that made up of particles in micrometre size range can cause respiratory health effects in both human and animals. Lastly, the sulphur oxides that emitted from motor vehicles burning fuel contain high concentration of sulphur.

Condition is getting worst due to the increasing of human population on earth. People keep purchasing cars without considering all these problems. However, it isn't too late to save ourselves. We could start carpooling from today onwards, take public transports, install catalytic converter on every single car and so on. I am afraid that we might have to wear poison gas mask around after 50 years later. Let's prevent this from happening!

The story between instant noodle and i

When you are hungry, what kind of food are you thinking about? Kentucky fried chicken, cheese cake…? Peoples usually would think about their favourite food when they are hungry. The first food that first come into my mind when I was hungry is instant noodles. Since I was young, I love to eat instant noodles. But I seldom consumed it because my mother always prevents me from cooking it. She says instant noodles are not good for our health. By the way, my desire to eating instant noodles becomes stronger and stronger because of the strictly controlled from my mother. So, every time when my mother when my mother is not at home, my sister and I would cook instant noodles secretly, without acknowledgement from our mother. There are very fun when we eat our favourite food, instant noodles, because we rarely have chance to consume it. Except that our mother is not at home. But we always discovered by our mother because we always remains some instant noodles in the basin of the kitchen. This was the funniest thing happen in my childhood. My favourite brand of instant noodles is cintan with the flavor of asam laksa . The taste of asam laksa of this brand are very special because it mixed with the taste of spicy and sour, and it really have fulfill my desire to taste two flavor at the same time.

Instant noodle was first invented in Japan. The price of instant noodles before are very expensive, but after the promoting, instant noodles become very commercial and its price become decreasing gradually. Nowadays, instant noodles are very cheaper staple food among Malaysian. It was very common food among Malaysian. But, instant noodles also got its disadvantages because of the low nutritional value. Instant noodles always get criticized among peoples as the unhealthy food. One packed of instant noodle contain high level of carbohydrate, fat, sodium and some may contain high level of protein. But it was low in vitamins, minerals, fibers and on the same times, it also contains high level of trans fat or saturated fat because of its manufacture process. Moreover, the flavoring powder in the instant noodles also contains high amount of MSG known as monosodium glutamate that may lead to headache, drowsiness, nausea if we consumes it too much.

Beside of this high level of carbohydrate, fat in instant noodles, the people that consume it in long period, would lead to malnutrition, obesity, high level of cholesterol, hypertension and so on. Actually instant noodle is a “no no” food for people who are on diet. One packet of instant noodles give you near to 2000KJ energy, about 65g of carbohydrate and almost 20g of fat. One packet of instant noodles may give you energy that is requiring by your body in whole day. The content of carbohydrate and also fat also excess the requirement for the normal adult in a day. So, if someone who are on diet consumed one packet of instant noodles in a day, would not help in the weigh lose because the amount of carbohydrate and fat are too high. But nowadays in order to fulfill the standard of health, the manufactures of instant noodle have successfully invent new type of instant noodles that are low in fat and without using monosodium glutamate as the flavoring. Besides, it also increases the content of fiber by using whole meal or wheat flour to make their noodles. The invention of new type of instant noodles has successfully get attention of many peoples especially who are on diet.

Eventhough, there are so many critics and side effect of instant noodles. But, I still love them. The most important thing is trying to reducing the times of consuming it. But love and enjoyed it when you having it. Enjoyed the moment when you having it, because after this time, you may have to wait a long time to consumed it again.

reference link: instant noodle(26 March 2010), http://en.wikipedia.org/wiki/instant_noodles, retrieved on 27 March 2010