Archive for July, 2009

Concentrators in Solar Cells

                        Sun is the ultimate source for power. We see that some calculators work with the help of solar cell. The calculator works with the help of solar power. Electricity is of prime importance from its origin. The sun shines with the energy of about 1000 W per square meter on the earth. We must utilize the power of the sun to the maximum extent. Solar cells utilization increases nowadays.

The advanced technology in the semiconductor is the use of concentrators. It increases the efficiency of the solar cell to a great extent. The light must be focused on the desired cells to gather more light. It follows the roadway of the sun using single-axis tracking. Two-axis tracking is used to adjust according to height variations of the sun. Concentrators are widely used in Electricity generation.

 It does not have a significant path in the area of photovoltaic. The focus of light on the cell increases the efficiency. The electrochemical cells have their active component in liquid. The light absorption is by the dye sensitizer. It makes use of cheap materials.

The electrochemical cells are now appearing with 120cm2 at an efficiency of about 7%. Photovoltaic cells can be close to heat source with 2420 F with the help of thermo photovoltaic cells. The institutes are investigating the low band gap III-V compounds. The Germanium is found to be the low cost in these alternatives.

KIDNEY STONES – 3

                Surgeries are carried only when the stones cannot able to pass through the urinary tract because of increased size, damaging the kidney tissues and when it blocks the flow of urine. Now the treatments become easier as open surgeries are not required. Depending on the nature and effect of stone, treatments are carried out.

                In Extracorporeal Shock Wave Lithotripsy (ESWL), shock waves are created outside the body and make it pass through the skin and body tissues so as to reach the stones. This is the commonly used treatment, the stones will get breakdown due to the waves into smaller particles so that they can travel through the urinary tract with ease along with the urine. Sometimes these smaller particles may also cause some discomfort during urination and also in the back. In such cases, doctors will insert a small tube into the ureter to help the particles pass. Frequent treatments may be needed in case the stones are not completely shattered.

                Sometimes ESWL will not be worthy, so doctors will prefer Percutaneous Nephrolithotomy to remove the stone. In this treatment, nephroscope instrument is used in the path created to the kidney from the back. For this treatment, patients have to stay in hospital for several days and also a small tube will be left in the kidney as it gets healed.

                Drinking lot of fluids especially water will help in the prevention of getting stones and also staying in hospital for several days. So, drink quarts of water and stay away from kidney stones.

KIDNEY STONES – 1

KIDNEY STONES – 2

 

KIDNEY STONES – 2

A person from a family having the history of kidney stones is more prone to get stones. Stones get developed because of the increased calcium content in the urine. Spinach, beefs, black Indian tea, wheat germ are the foods that contain high oxalate. Strawberries, grapes, green pepper, fruit cake and liver contains moderate amount of oxalate content.

                Kidney stones will not show or cause any symptoms, but extreme pain occurs when the stone passes in the urinary tract. Cramping pain in the back and in the region of kidney can be felt. A person may feel burning sensation while passing urine and feels frequent urination. Kidney can be noticed through x-rays, blood and urine test will give some idea about the stone formation. Doctors will do computerized tomography (CT) scan to scan the urinary system, based on the results treatment will be carried out for the patient. Drinking lot of water will prevent the stone formation and also it will take the stones along with the urine.

Drinking about two to four litres a day will help in preventing the stone formation and also the amount of urine can be in the range of one to two litres. The quantity of meat, fish and poultry intake needs to be less as it increases the acid content in the urine. If the stones cannot be controlled by drinking lot of water, then doctors will go for medicines so as to reduce the amount of cystine in the urine. Then also if it cannot be kept under control then surgeries will be done to remove the stone.

 

KIDNEY STONES – 1

KIDNEY STONES -3