Wonders of the world: Spiders

Tree spider

When I was a child like my other friends, I was scared of spiders. Even now when I see a spider in my room, certainly I do not scream, but yet, I avoid them and try to chase them out from my room. When I grew up little by little, I wanted to get rid of this fear and crazy imaginations about spiders, so I started reading about spiders in order to get familiarize with these little fascinating creatures.

We all know that spiders are disliked by many people due to their lack of knowledge about spiders. According to the taxonomy of spiders, they belong to the class Arachnida Phylum Arthropoda. These spiders are carnivores which mean they feed on small insects or flesh. They do it by trapping their pray using their web or by hunting on ground. In addition, these spiders can be seen all over the world except in air since they do not have wings to fly and in ocean since they are air-breathing animals. Yes, there are some spiders who can live under water such as Diving Bell Spider ( Argyroneta Aquatica) but they also need air. In this case they trap air in a bubble held by hairs on its abdomen and legs.

Another reason is their size and the appearance which give an expression that they should not be petted or loved, they are venomous and dangerous. When we consider about their size, most spiders are relatively small (2-10 mm) but there are exceptions like Tarantula whose body length will extend up to 80-90 mm. Even though size varies from one spider species to another, their body consists of two main parts. First part is the “Cephalothoraxe” (Prosoma) which is the anterior part and the other part which is the posterior part, known as “Abdomen” (Opisthosoma)

CONSTRUCTED WETLANDS AS A METHOD OF WASTEWATER TREATMENT

          Since most chemical reactions take place in water based medium, water plays a major role in industrial world. With the polar nature of water it easily gets polluted from those chemical and biological ingredients use in manufacturing process. This polluted water is called industrial effluents or simply the wastewater. Since industrial wastewater contain toxic chemical compounds like Cyanides, biological waste like plant materials and pathogens, toxic heavy metals like Cadmium, Lead, exceeding the accepted levels for human use. When this wastewater released in to natural water bodies it may result social and health problems to the people living around the water resource and also to the people who use it for day today work. 

Minamata Disease (methylmercury poisoning) on Public Health & Social Justice 

socialmedicine.org

In early days people tends to release this waste water to natural water bodies without a proper treatment. Therefore in early days outbreaks due to hazards waste were common. Minamata outbreak in Japan is such a disaster coursed by not having a proper treatment for wastewater. Wastewater treatment is an expensive process, if we are using conventional methods like chemical precipitation, Ion exchange; Reverse Osmosis and Electro dialysis. Not only they are expensive but also they produce toxic sludge therefore small industries won’t consider about having a wastewater treatment plant within their manufacturing plants due to the high production cost. Instead they release wastewater to the nearby water stream without treating it.

COAL FIRED ELECTRICITY GENERATION.

              Energy, we all need it to do a work. As humans we use energy stored in our body. But most of the time energy stored in our body is not sufficient enough to finish the required work. Therefore we use machines to do our work. Most of these machines driven by electricity which makes electricity to play a major role in the form of energy for development of a country. Electricity generation required an efficient energy source. Energy sources that we use today is limited resulting a global problem called energy crisis.s

              Hydro power is the most common energy source that people familiar with the electricity generation in Sri Lanka. Other than that developed countries use nuclear energy to generate electricity. Fossil fuels, geothermal energy is also using for electricity generation. Due to the modern climatic changes hydro power stations cannot operate at their maximum capacity. And Nuclear power plants need more advanced technology and more capital which cannot afford by developing country like Sri Lanka, which lead to find a convenient alternative energy source to generate electricity. Such convenient alternative energy source is Coal. Coal is a solid fossil fuel which containing Carbon and it is the most impure of fuels, its impurities range from trace quantities of many metals including uranium and thorium to much larger quantities of aluminum and Iron to still larger quantities of impurities of such as Sulfur. 

Salt and Heart diseases

           In modern society most people tend to have low salt diets. When we questioned about it they use to tell that one of their family members is suffering from a cardiac disease. So what is the relationship between salt and heart diseases? First I was confused by it because people started to use salt in their foods thousands of years ago. And salt contains Na⁺ (sodium) which is an important element in human body.

        Salt or Sodium chloride (NaCl) is used as a preservative as well as a seasoning in the ancient time. And by now we know that Sodium is an essential element in human body where as having Sodium in the fluid outside cell as the major cation, is important to a correct functioning of the nerve system since action potential occurs due to the Na⁺ (Sodium) K⁺ (Potassium) ion distribution across the cell membrane. And Sodium helps to maintain electrochemical balance in the body. This important element of Sodium (Na⁺) gets in to the body mainly through salt.

Wonders of the world (Firefly bug)

      Few years back when I was in grade one, me and my friends used to collect Tortoise beetles as our hobby. Whenever we caught a new Tortoise beetle which differed from others we brought them to school and showed them to others by saying that we got a new Tortoise beetles that you guys don’t have. And we explained how we caught them, from where we caught them, things they eat and that kind of funny stuff. Those are wonderful memories and i'm sure you also have those kinds of sweet memories with you. Back to story, but one day I caught a bug little bit different from Tortoise beetles. Usually, Tortoise beetles are hemispherical in shape and have bright colors. But the one that I caught was little bit elongated and thin. So I thought I caught a new Tortoise beetle that none of my friends have caught early. Since my friends don’t have such a Tortoise beetle with them, I was so happy. So that I can show my new Tortoise beetle and tell them about it.

I put my new friend with my other Tortoise beetles. So that I can take it to school on the next day. But at night I suddenly got waken up by a strange light emitted from my Tortoise beetle container. I was afraid and I called my mother to tell about this. She told me that she will explain it in the morning and asked me to sleep. But I couldn’t sleep all that night. 

FABRIC SOFTENERS/FABRIC CONDITIONERS

Fabric softeners or Fabric conditioners are liquid product that used while laundering to make cloths soft and eliminate static cling. Fabric softeners or conditioners are introduce in early 20^th  century in cotton industry since dye which use to colour the fibers make them feel harsh. Therefore cotton softeners were introduce to improve the quality of the cotton. With the rapid development in Industrial Chemistry more effective fabric softeners make their way in to commercial market. 

When fabric softener is introduce in to the washing cycle, Fabric softener tends to deliver a variety of attributes to the cloth. Such as superior softness, Improve iron glide, Reduce the winker formation during wash cycle, Improve winker removal after washing, Better colour retention and enhance the stain protection.