Kenaf Powder Used to Create New WPC Material

Wood-plastic composites (WPCs) are one of the fastest growing construction components in the wood composites industry. Their popularity is due to low maintenance, high durability, and resistance to termites and other insect attacks. However their widespread usage has been limited due to their high cost in production and in some instances low strength.

The present study focused on assessing the suitability of kenaf core fraction (about 65%of the whole stem of the plant) in powder form as filler material. Kenaf powder, processed from its core fibre, has been shown to offer one potential solution to the increasing scarcity of traditional filler materials. Kenaf stems contain two distinct fibre types, bast and core. Dosing with maleic-anhydride-modified polypropylene (MAPP) in the right amount displayed not only to bridge the interface between the ground kenaf core (GKC) and plastic in the present WPCs, improving stress transfer and increasing their strength and stiffness, but also allow a higher filler loading. Reducing the amount of plastic and increasing the amount of GKC, without sacrificing strength, stiffness or durability, would result in greener WPC products.

Researchers examined the possibility of replacing sawdust with GKC and measured the mechanical properties of the resulting composites. They also looked at the effect of increasing maleic anhydride modified polypropylene (MAPP) dosage. Material preparation included GKC drying followed by high intensity blending with polypropylene (PP), coupling agents (MAPP) pellets, and feeding this into a counter-rotating twin-screw extruder for compounding. Compounded blends were then fed to an injection-moulding machine to produce boards of dimensions 153mm x 153mm x 3mm. Specimens were cut from the boards for tensile and bending tests in five replicates. GKC formulation gave the highest average tensile strength, modulus of rupture and modulus of elasticity.

Reducing the amount of plastic and increasing the amount of GKC, without sacrificing strength, stiffness or durability, would result in greener WPC products. The researchers recommend that additional testing and extended research is necessary to investigate the strength of WPC on mechanical properties of modulus of elasticity (MOE) and modulus of rupture (MOR) by carrying out impact test and compressive test which could reveal new discoveries about high filler loading WPCs.

Lab-Evolved Enzyme Starves Tumors

Tumors can grow quickly only when they’re well fed, so doctors seek ways to starve the malignancies. Realizing that cancer cells consume more methionine than healthy cells do, researchers engineered a novel human enzyme that degrades the amino acid. In experiments using mice, the protein stopped tumor growth.

However, the bacterial enzyme causes a strong immune reaction in primates, making it a poor drug candidate, says George Georgiou of the University of Texas, Austin. Also, the enzyme’s half-life in human serum is only two hours, he says. Such a short lifetime would mean patients would have to take larger doses of the enzyme to see any benefit, adds Georgiou.

A human MGL would be a better cancer drug than the bacterial enzyme, Georgiou hypothesized. Unfortunately, no such enzyme exists. He and his team set out to make one.

They selected cystathionine gama-lyase (CGL) as a starting point because it is a human enzyme that closely matches MGL in sequence and catalyzes a similar chemical reaction. Plus, CGL has a longer half-life in serum than MGL does. After comparing the sequences of the two enzymes, the researchers realized that they had to make CGL’s active site more hydrophobic to make it interact with methionine. Compared to cystathionine, which is the molecule CGL binds and reacts with, methionine is greasier.

To modify the enzyme’s active site, the researchers created over 2,000 mutated versions of CGL. They then screened the mutants to determine how fast each chewed up methionine and produced methanethiol (also known as Methyl mercaptan) and alpha-ketobutyrate. The team monitored the reaction by adding the compound 3-methylbenzothiazolin-2-one hydrazone, which reacts with alpha-ketobutyrate to produce an ultraviolet-absorbing molecule. The enzyme that was most efficient at catalyzing the reaction differed from CGL by just three amino acids and had a half-life of 78 hours in human serum.

“It’s very impressive,” says Eugene Frenkel of the University of Texas Southwestern Medical Center. They are “well on their way” to developing a medicine, he says. He thinks the enzyme’s current rate of methionine chewing would work against a wide range of fast-growing tumors. Still, Georgiou wants to increase the enzyme’s speed, which would make a lower dose of the protein able to slow tumor growth.

Know More About Pesticides and Insecticides

None of us like the sight of insects and hence most of us do a pest control at home at regular intervals to keep the insects and pests away. In fact, we keep ourselves well-equipped against these insects. The moment we see a mosquito or cockroach creeping inside our house, we immediately grab a can of insecticide and spray on it. The insect instantly dies.

Pesticides and insecticides are a mixture of substances that help in destroying, preventing or controlling insects and pests. By spraying pesticides and insecticides, you not only keep the insects out of your house but also make sure that you have a disease free life.

It is said that humans started using pesticides and insecticides well before 2000 years
ago. The first form of pesticide was elemental sulphur dusting which was used in Sumer around 4,500 years ago. Around 15th century, toxic substances like arsenic, lead and mercury were used. By 17th century, nicotine sulphate was extracted from tobacco leaves and was used as insecticide. Around 19th century, two more natural substances like pyrethrum which is derived from chrysanthemums, and rotenone which is derived from the roots of tropical vegetables came into existence.

In 1950′s, Paul Muller discovered that dichlorodiphenyltrichloroethane or DDT, yet another chemical, was a better option and was more effective than the rest of the variants. DDT replaced all the other types by 1975. Since then, DDT and pyrethrin compounds have dominated the insecticide and pesticide industry. Besides this, herbicides also gained lot of popularity. Herbicides contained triazine and other nitrogen-based compounds.

How do they work?
Pesticides and insecticides contain tons of bug killing microns. In fact even after the
sprayed medicine dries, the microns still exist and kill the bugs.

Bugs also have nervous system just like mammals. Their nervous system contains nerves that pass impulse to the brain and gets a sensory reply back. When the pesticides and insecticides are sprayed, impulses that are sent to the brain do not stop. The impulses are similar to those of hunger pangs. Due to excess impulses, the organs of the bugs break down and as a result the bug dies.

Now that you know what pesticides and insecticides are made of and how they work, it is important to read the instructions before using one.

The Histories Of Different Kinds Of Balloons

The colourful and beautiful balloons have always managed to enchant us. Every one of us loves balloons; no matter how old we are. The colourful balloons indeed manage to fascinate each one of us. Every celebration has balloons involved. No birthday parties or marriage parties are complete without balloons. But have you ever given a thought on how balloons came into existence? Let us find out.

Hot-air Balloons
Hot-air balloons were invented in the same year as gas or latex balloons. Brothers Joseph and Etienne Montgolfier were paper makers in France. One day, they noticed when their kitchen gas was lit; pieces of paper flew in the air due to hot air that was emitted from the gas. They decided to experiment with paper bags. In June 1782, they made a bag out of cloth which was lined with paper. The lit a fire underneath and the balloon floated for a mile and a half before landing.

In Paris, J A C Charles heard about this experiment and in August, he sent up a small balloon filled with hydrogen. Later in 1783, the first balloon carried two people and the balloon travelled 8 km for 25 minutes. Post this, today, the balloons have undergone lot of changes and man is in a position to fly just like the birds.

Gas Balloons
The word balloon finds its origin from the French word, “ballon” which means a huge ball. Also, the word balloon has other origins like Latin word “ballone” which again refers to a ball or from old German word “balla” which also means a ball.

It is believed that the first balloon was discovered by Bartolomeu de Gusmao and it made its first public appearance during an exhibition in Lisbon. Also, it is believed that the first rubber balloon was discovered by the famous scientist Micheal Faraday in 1824. Faraday filled the balloon with hydrogen gas and called it caoutchoucs.

However, it was found that helium atoms easily escaped from the pores of the cumene or rubber balloons and hence the balloons were later treated with polymer solution like hi-float gels to keep the gas intact for longer.

Later in 1970s, foil balloons were introduced wherein aluminised plastic films were found to be more durable and less permeable and also helped in keeping the helium gas from escaping. However, it was found that foil balloons were less flexible as compared to rubber balloons.