~ LAB SESSION =) ~

This is my last post for the assignment...^^
our group lab session photos from the 1st lab until the last... ^^

~ How INK works??? ~

Everyday when we study, when we work, we write with pen…

But, do you know how pen work?

Today, I just want to write something about gel pen here…
In more details, I just want to discover what inside the gel pen ink?????

Gel Pen

A gel pen uses ink in which pigment is suspended in a water-based gel. Because the ink is thick and opaque, it shows up more clearly on dark or slick surfaces than the typical inks used in ballpoint or felt tips pens. They can be used for many types of writing and illustration.

The general design of a gel pen is similar to that of a regular rollerball pen, with a barrel containing the writing mechanism and a cap, and a reservoir filled with ink. The barrels can be created in many different sizes and designs; some have finger grips of rubber or plastic. The size of the nib or pen tip ranges from 0.25 mm to 1.5 mm.

Inks for Gel Pen

The main advantage of gel ink is its high viscocity, which supports a higher proportion of pigments in the medium. The pigments are typically copper phthalocyanine and iron oxides, and the gel is made up of water and biopolymers, such as xanthan gum, as well as some types of polyacrylate thickeners. The pigments are opaque, and gel pens are available in a rainbow of bright and pastel colours.

Copper Phthalocyanine

Copper phthalocyanine dyes are produced by introducing solubilizing groups, such as one or more sulfonic acid functions in CPC (Cetylpyridinium chloride) structure. These dyes find extensive use in various areas of textile dyeing (Direct dyes for cotton), for spin dyeing and in the paper industry.

Copper Phthalocyanine structural formula

Iron oxides

Iron oxides are chemical compunds composed of iron and oxygen. Altogether, there are sixteen known ison oxides and oxyhydroxides.

--FeO, iron(II) oxides, (wustite)
--Fe3O4, iron(II,III) oxides( magnetite)
--Fe2O3, iron(III) oxides , (Hematite)
- α-Fe2O3, hematites
- β-Fe2O3
- γ-Fe2O3, maghemite
- ε-Fe2O3

Xanthan gum

Xanthan gum is a polyssacharide used as a food additive and rheology modifier.
One of the most remarkable properties of xanthan gum is its capability of producing a large increase in the viscocity of a liquid by adding a very small quantity of gum, on the order of one percent.

xanthum gum sample

Polyacrylates (Acrylate polymer)

An acrylate polymer belongs to a group of polymers which could be referred to generally as plastics. They are noted for their transparency and resistance to breakage and elasticity. Also commonly known as acrylics or polyacrylates.

Used

--Sodium polyacrylate -water soluble thickeners
--Super glue" is a formulation of cyanoacrylate.
--Polyacrylate emulsion, are used as binder for outdoor and indoor "latex" house paints.

Polyacrylate structural formula

Ballpoint pens use a paste ink based on dye solute in an alcohol solvent. Compared to ballpoint pens, gel pens:

--Create a bolder line
--Smudge less
--Have occasional skips, due to the ball being less evenly coated with ink
--Use more ink, leading to more frequent refills or replacements

For gel pen, we normally can refill it after we finish the ink, but if you use ballpoints pen, you cannot do this. For me , this is quite convenience^^

Here are some gel pen photos.

Most common one- PILOT Gel Pen

Parker gel pen and ink (present for daddy…haha^^)

Although i just discover gel pen ink, but i think ink is a very important things in our life...

Wthout it, we cannot write, cannot print, there will be no photos....

Then, life will become boring...>.<

~ OH MY GOD!!! ~

Why the umbrella spoiled??????
It’s all ACID RAIN fault!!!!

"It has often been observed that the stones and bricks of buildings crumble more readily in large towns where much coal is burnt.... I was led to attribute this effect to the slow but constant action of acid rain." Robert Angus Smith 1856

"Acid rain" is a popular term referring to the deposition of wet (rain, snow, sleet, fog and cloudwater, dew) and dry (acidifying particles and gases) acidic components. A more accurate term is “acid deposition”.

Unpolluted rain

“Clean” or unpolluted rain has a slightly acidic pH of about 5.2, because carbon dioxide and water in the air react together to form carbonic acid, a weak acid (pH 5.6 in distilled water), but unpolluted rain also contains other chemicals.

H2O(l) + CO2(g) → H2CO3(aq)

Carbonic acid then can ionize in water forming low concentrations of hydronium and carbonate ions:

2 H2O (l) + H2CO3 (aq) CO32− (aq) + 2 H3O+ (aq)

Acid rain

Acid rain is rain or any other form of precipitation that is unusually acidic. It has harmful effects on plants, aquatic animals, and infrastructure. Acid rain is mostly caused by human emissions of sulfur and nitrogen compounds which react in the atmosphere to produce acids. The sulfur and nittrogen compounds from human sources, such as electricity generation, factories, and motor vehicles. Acid rain has acidity about pH 5.0 or less. Most acid deposition ranges from pH 4.3 to 5.0. For industries areas, pH 2.4 and below can be found.

pH scale to show the pH diference between unpolluted rain and acid rain

Formation of acid rain

Combustion of fuels creates sulfur dioxide and nitric oxides. They are converted into sulfuric acid and nitric acid.

Gas phase chemistry

In the gas phase sulfur dioxide is oxidized by reaction with the hydroxyl radical via an intermolecular reaction :

SO2 + OH· → HOSO2·

which is followed by:

HOSO2· + O2 → HO2· + SO3

In the presence of water, sulfur trioxide (SO3) is converted rapidly to sulfuric acid:

SO3 (g) + H2O (l) → H2SO4 (l)

Nitrgen dioxide reacts with OH to form nitric acid:

NO2 + OH· → HNO3

Chemistry in cloud droplets

When clouds are present, the loss rate of SO2 is faster than can be explained by gas phase chemistry alone. This is due to reactions in the liquid water droplets.

Hydrolysis
Sulfur dioxide dissolves in water and then, like carbon dioxide, hydrolyses in a series of equilibrium reactions:

SO2 (g) + H2O SO2·H2O
SO2·H2O H+ + HSO3−
HSO3- H+ + SO32−

Oxidation
There are a large number of aqueous reactions that oxidize sulfur from S(IV) to S(VI), leading to the formation of sulfuric acid. The most important oxidation reactions are with oozone, hydrogen peroxide and oxygen (reactions with oxygen are catalyzed by iron and manganese in the cloud droplets).

The formation of acid rain

The harmful effects

1) Surface waters and aquatic animals
-- Both the lower pH and higher aluminum concentrations in surface water that occur as a result of acid rain can cause damage to fish and other aquatic animals. At pHs lower than 5 most fish eggs will not hatch and lower pHs can kill adult fish.

2) Soils
-- Some microbes are unable to tolerate changes to low pHs and are killed. The enzymes of these microbes are denatured (changed in shape so they no longer function) by the acid. The hydronium ions of acid rain also mobilize toxins such as aluminium, and leach away essential nutrients and minerals such as magnesium.

2 H+ (aq) + Mg2+ (clay) 2 H+ (clay) + Mg2+ (aq)

3) Forest
-- High altitude forests are especially vulnerable as they are often surrounded by clouds and fog which are more acidic than rain. Other plants can also be damaged by acid rain.

"Bald tree”- without leaves!!!

4) Building and Historical monuments
-- Damage to certain building materials and historical monuments. This results when the sulfuric acid in the rain chemically reacts with the calcium compounds in the stones (limestone, sandstone, marble and granite) to create gypsum, which then flakes off.

CaCO3 (s) + H2SO4 (aq) CaSO4 (aq) + CO2 (g) + H2O (l)

India’s Taj- Mahal which also affected by acid rain. The mausoleum built by the Mughal Emperor Shah Jahan for his beloved wife Mumtaz Mahal is losing its white luster and turning a sickly pale shade.

The corroded monuments

5) Human health
-- The effects of inhaling particulate matter have been widely studied in humans and animals. It included asthma, lung cancer, cardiovascular issues, and premature death.

This acid rain penomenon let me remember a song in my childhood times~~~

♪ “RAIN RAIN GO AWAY~~~” ♪
Acid rain please go away !!!

♥ We can use car pooling method or try to walk to a destination which is in short distance.
♥ We can use an alternative energy source such as solar energy, wind energy.
♥ Plant a tree!! The tree will absorb some of the polluted air and put out clean, fresh oxygen.
♥ Educate other people. One person really can make a difference; think about if other people thought that way, rather than just saying "Well, if they can do it, I can do it".
♥ We can try the best way to save our mother earth, to save ourselves!!!!

GO GO GO AWAY!!!!

~ ♥ Yummy yummy!!! I love chocolate!!! ♥ ~

WOOHOOO~~~
I like chocolate…it’s make me happier when eating it^^
You can try one when you are very stress, you will feel better and become more energetic after consume it…=D
I found out that it is a so called “happy food” in my friend- Jhun Yuan chemistry’s blog.^^

There are several types of chocolate.

1) Pure, unsweetened chocolate ♥
It contains primarily cocoa solids and cocoa butter in varying proportions, but normally we didin’t consume it in this form.

2) Sweet chocolate ♥
It is combining chocolate and sugar.

3) Milk chocolate ♥
It is a sweet chocolate adding condensed milk or milk powder.

4) White chocolate ♥
It contains cocoa butter, sugar, and milk solids but no cocoa solids.
(It does not contain any cocoa solids. Because of this, many countries do not consider white chocolate as chocolate at all. =.=”)

5) Dark Chocolate ♥♥♥ [Highly Recommended^^]
It is produced by adding fat and sugar to the cacao mixture.

6) Semisweet chocolate ♥
It is a chocolate with a low sugar content.

7) Bittersweet chocolate ♥
It is a chocolate liquor to which some sugar , more cocoa butter, vanilla and sometimes lecithin have been added.

8) Unsweetened chocolate ♥
A pure chocolate liquor, also known as bitter or baking chocolate. It is unadulterated chocolate: the pure, ground, roasted chocolate beans impart a strong, deep chocolate flavor.

Chocolate comprises a number of raw and processed foods produced from the seed of the tropical cacao tree.

Cacao tree seed

Chocolate
Chocolate contains alkaloids such as theobromine and phenetylamine, which have some physiological effects in humans. (For the “theobromine”, I had already analyse it in my previous blog ”You like Coca-Cola?”. So, I’ll just analyse phenethylamine here.)

Phenethylamine
Phenethylamine (PEA) is an alkaloid and monoamine compound. Phenethylamine is a natural compound biosynthesized from the amino acid phenylalanine by enzymatic decarboxylation. It is also found in many foods such as chocolate, especially after microbial fermentation.

Phenethylamine structural formula

About chemical properties
Phenethylamine is an aromatic amine, which is a colorless liquid at room temperature. It is soluble in water, ethanol, and ether. Similar to other low-molecular-weight amines, it has a fishy odor. Upon exposure to air, it forms a solid carbonate salt with carbon dioxide. Phenethylamine is strongly basic and forms a stable crystalline hydrochloride salt with a melting point of 217 °C. Phenethylamine is also a skin irritant and possible sensitizer.

[Highly recommended à Dark chocolate]
Dark chocolate, with its high cocoa content, is a rich source of the flavonoids epicatechin and gallic acid, which are thought to possess cardioprotective properties. Dark chocolate has also been said to reduce the possiblility of a heart attack when consumed regularly in small amounts.
Ingredients of dark chocolate: sugar, cocoa butter, cocoa liquor, and (sometimes) vanilla

Circulatory benefits caused by epicatechin
Cocoa or dark chocolate benefits the circulatory system. Other beneficial effects suggested include anticancer, brain stimulator, cough preventor and antidiarrhoeal effects.

Epicatechin (Catechin)
Catechin was first isolated from the plant extract catechu. They are present in nearly all teas. The health benefits of catechins have been studied extensively in humans and in animal models. Reduction in atherosclerosis plaque was seen in animal models.

Structural formula of epicatechin

There are also some bad effect from others chocolate (not dark chocolate!!!) Please refer the above diagram.

Reminder!!!
Storage of chocolate
-- Ideal storage temperature : between 15°C and 17 °C
-- Relative humidity of less than 50%
-- Stored away from other foods as it can absorb different aromas
-- Stored in a dark place

Many people don’t like chocolate because they think it will cause obesity…
How about dark chocolate?
If you consume it in a moderate way. It is also a healthy food for us~~~
ENJOY YOUR DARK CHOCOLATE!!! ^^
Hoho~~~ Let’s share some cute chocolate photos here^^

Couple chocolate^^ (Very hot in Valentine’s day =))

Chocolate made high-heels ^^

SO SWEET~~~~~~ ^^

What a nice dessert…yummy Yummy~~~^^

Pendrive also like chocolate^^

~ What you wearing everyday? ~

I’m going to hang out with my friends later at Midvalley...

What should I wear today?

My orange T-shirt, red stripes singlet, light green dress, black trousers, blue shorts OR purple skirt??? Erm…. everytime before go out, many girls will stand in front of their wardrobe and think it for a long time...

"What should I wear today??? "

HAHA~~~

But today I just want to discover... What are we wearing actually everyday? What made up our clothes? Have you ever take a look on your shirt, maybe at the innerside of your clothes, or it is located near the collar….

There is a small piece of fabric which have sign on it….

It looks like this :

from----->

This small piece of fabric will tell us the ingredients of the clothes….
There are different ingredients to made up our shirt….
But I will only select several type of ingredients and analyse it here….
I will show you some little fabric and their OWNER here….^^

from------>

from------>

from---->

In my observation, I find out that most of the cloths are made up of this 3 ingredients :

1) Cotton
2) Rayon
3) Polyester

So, I will focus on these 3 types of ingredients.

Cotton
Cotton is a soft, staple fiber that grows in a form known as a boll around the sseeds of the sotton plant, a shrub native to the Americas, India and Afrika. The fiber most often is spun into yarn or thread and used to make a soft, breathable textile, which is the most widely used natural-fiber cloth in clothing today.

Used
It can used to be made towels, blue jeans, socks, T-shirt, underwear, bed sheet… Almost all the things you used in your daily life are made up of cotton.

Cotton ready to harvest

Rayon
Rayon is a manufactured regenerated cellulosic fiber. Because it is produced from naturally occurring polymers, it is neither a truly synthetic fiber nor a natural fiber; it is a semi-synthetic fiber . Rayon is known by the names viscose rayon and art silk in the textile industry. It usually has a high lustre quality giving it a bright shine. Rayon contains the shemical elements carbon, hydrogen, and oxygen.

Used
1) Apparel(e.g. blouses, dresses, jackets, suits, ties, hats, socks)
2) Furnishings (e.g. bedspreads, blankets, curtain)
3) Industrial uses (e.g. medical surgery products, tire cord)
4) Other uses (e.g. yarn, feminine hygiene products)

A sample of rayon on a skirt

Another skirt with different texture

Rayon thread

Cellulose is treated with alkali and carbon disulfide to yield rayon.

(Click the diagram to show the equation clearly.^^)

Polyester

Polyester is a category of polymers which contain the ester functional group in their main chain. Although there are many polyesters, the term "polyester" as a specific material most commonly refers to polyethylene terephthalate (PET). Polyesters include naturally-occurring chemicals, such as in the cutin of plant cuticles, as well as synthetics through step-growth polymerization such as polycarbonate and polybutyrate. Natural polyesters and a few synthetic ones are biodegradable, but most synthetic polyesters are not.

Characteristic
1) Polyesters as thermoplastics may change shape after the application of heat.
2) Polyester fibers have high tenacity and E-modulus as well as low water absorption and minimal shrinkage in comparison with other industrial fibers.

Used

Apparel, Bed sheets , rope, safety belt, comforter, films, bottle…

Polyester structural formula

Polyester ribbon

That is what we wearing , sleeping on and using everyday….
Just to share this information with you….
Or you have some shirt like this???^^

directly show the ingredients outside the shirt?