Spectroscopic studies on nano hydroxyapatite/polymers composites

Spectroscopic studies on nano hydroxyapatite/polymers composites

Автор: El Metwally Abdelrazek,Gamal S. El-Bahy and Mousa Abdelalem Alam

Nano-particles of hydroxyapatite (HAp) were prepared via an in-situ biomimetic process with polyacrylic acid (PAAc) as a host polymeric material. Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) were used to test the physical and chemical characteristics of biocomposites. The formation of hydroxyapatite is confirmed by energy dispersive X-ray (EDX) spectroscopic analysis. Chemical binding between inorganic HAp and PAAc was investigated and discussed

New Approaches to Micro-electronic Component Cooling

New Approaches to Micro-electronic Component Cooling

Автор: Xiangqi Wang,Arun S. Mujumdar and Christopher Yap

Over the past three decades, societal demands have resulted in extremely compact yet powerful electronic devices. Due to increased packaging density, improved performance of electronic devices has caused continuing increase in power dissipation of systems. Hence, effective thermal management or cooling of the electronic devices is a key to ensure their reliable and efficient performance. Considering the limitation of air-cooling method, other cooling techniques have to be carried out to meet the requirement. Several new approaches for electronic cooling were proposed and investigated numerically and experimentally in this book. The methods include introduction of tree-shaped microchannel network in heat sink designs, addition of phase change materials, and use of nanofluids. Results demonstrated that the new approaches have high potential in thermal management of micro-electronic components. This work contributes to a more fundamental understanding of the…

Treatment of Water by Biodegradable Coagulant Developed from Mango Pit

Treatment of Water by Biodegradable Coagulant Developed from Mango Pit

Автор: Abdul Qadeer Dayo,Inamullah Bhatti and Khadija Qureshi

Coagulants are widely used for the removal of turbidity. Salts of Aluminum are the most commonly used coagulants for water treatments,these coagulants are not safe due to highly carcinogenic containments. From last two decade researchers are paying attention on the development of natural and biodegradable coagulants from plant residue and animal tissues. Developed organic coagulants were acknowledged for human health safety and produce lower quantity of sludge. Pakistan produces almost 1.7279 MT/year of Mango. Mango kernel mass average is 9 to 23% of mango on wet basis. Coagulant was prepared from ‘Sindhri» Mango kernel and passed from micro-filtration rig for the highest removal of generated flocks.

Биологическая активность почвы при внесении 2,4,6-тринитротолуола

Биологическая активность почвы при внесении 2,4,6-тринитротолуола

Автор: Инна Кормильцева, Борис Куриненко und Галина Яковлева

2,4,6-тринитротолуол (тринитротолуол, ТНТ) — широко распространенное по всему миру взрывчатое вещество, основная часть которого депонируется почвенным покровом. В многочисленных исследованиях показан высокий токсический потенциал ТНТ по отношению к различным живым организмам, в связи с чем предпринимаются многочисленные попытки ремедиации почв, загрязненных тринитротолуолом. Вместе с тем в литературе до сих пор отсутствуют данные о влиянии ТНТ на комплекс параметров, составляющих биологическую активность почвы, приводятся лишь факты негативного влияния на отдельные биохимические процессы почвы. В данном исследовании предпринимается попытка интегральной оценки биологической активности почвы, загрязненной ТНТ.