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排序方式: 共有403条查询结果,搜索用时 15 毫秒
71.
Sundaresan Mohanraj Shanmugam Kodhaiyolii Mookan Rengasamy Velan Pugalenthi 《International Journal of Hydrogen Energy》2014
The effects of FeSO4 and synthesized iron oxide nanoparticles (0–250 mg/L) on fermentative hydrogen production from glucose and sucrose, using Enterobacter cloacae were investigated, to find out the enhancement of efficiency. The maximum hydrogen yields of 1.7 ± 0.017 mol H2/mol glucose and 5.19 ± 0.12 mol H2/mol sucrose were obtained with 25 mg/L of ferrous iron supplementation. In comparison, the maximum hydrogen yields of 2.07 ± 0.07 mol H2/mol glucose and 5.44 ± 0.27 mol H2/mol sucrose were achieved with 125 mg/L and 200 mg/L of iron oxide nanoparticles, respectively. These results indicate that the enhancement of hydrogen production on the supplementation of iron oxide nanoparticles was found to be considerably higher than that of ferrous iron supplementation. The activity of E. cloacae in a glucose and sucrose fed systems was increased by the addition of iron oxide nanoparticles, but the metabolic pathway was not changed. The results revealed that the glucose and sucrose fed systems conformed to the acetate/butyrate fermentation type. 相似文献
72.
M. Venkatachalam M.D. Kannan S. Jayakumar R. Balasundaraprabhu A.K. Nandakumar N. Muthukumarasamy 《Solar Energy Materials & Solar Cells》2008,92(5):571-575
CuInxGa1−xSe2 bulk compound of three different compositions x=0.75, 0.80 and 0.85 have been prepared using individual elements of copper, indium, gallium and selenium. Thin films of CuInxGa1−xSe2 have been deposited using the prepared bulk by electron beam evaporation method. The structural studies carried on the deposited films revealed that films annealed at 400 °C are crystalline in nature exhibiting chalcopyrite phase. The position of the (1 1 2) peak in the X-ray diffractogram corresponding to the chalcopyrite phase has been found to be dependent on the percentage of gallium in the films. The composition of the prepared bulk and thin films has been identified using energy dispersive X-ray analysis. The photoluminescence spectra of the CuInxGa1−xSe2 films exhibited sharp luminescence peaks corresponding to the band gap of the material. 相似文献
73.
Tensile and Impact Properties of Shielded Metal Arc Welded AISI 409M Ferritic Stainless Steel Joints
The present study is concerned with the effect of filler metals such as austenitic stainless steel, ferritic stainless steel and duplex stainless steel on tensile and impact properties of the ferritic stainless steel conforming to AISI 409M grade. Rolled plates of 4 mm thickness were used as the base material for preparing single pass butt welded joints. Tensile and impact properties, microhardness, microstructure and fracture surface morphology of the joints fabricated by austenitic stainless steel, ferritic stainless steel and duplex stainless steel filler metals were evaluated and the results were reported. From this investigation, it is found that the joints fabricated by duplex stainless steel filler metal showed higher tensile strength and hardness compared to the joints fabricated by austenitic and ferritic stainless steel filler metals. Joints fabricated by austenitic stainless steel filler metal exhibited higher ductility and impact toughness compared with the joints fabricated by ferritic stainless steel and duplex stainless steel filler metals. 相似文献
74.
Vishal Sharma Venkatachalam Maivizhikannan Vempuluru Navakoteswara Rao Suneel Kumar Ajay Kumar Ashish Kumar Muthukonda Venkatakrishnan Shankar Venkata Krishnan 《Ceramics International》2021,47(7):10301-10313
In this work, an attempt has been made to fabricate multifunctional composite photocatalysts by coupling sea urchin shaped ZnO with MoS2 and polyaniline (PANI) sheets, and a significant improvement in photocatalytic activity was perceived with composites in comparison to pristine components. It was found that the ternary ZnO–MoS2-PANI photocatalyst showed excellent adsorptive decomposition of organic pollutants natural sunlight irradiation. In addition, enhanced photocatalytic hydrogen evolution was also evidenced, which revealed the multifunctional nature of the photocatalysts. In the case of organic pollutant decomposition, the presence of MoS2 in ZnO–MoS2-PANI offers abundant catalytic active sites which result in adsorption of the pollutants and boost the photocatalytic activity. While for the photocatalytic hydrogen evolution, the binary ZnO-PANI composite showed the utmost activity in comparison to the pristine components and ZnO–MoS2-PANI, which is due to the fact that the higher loading of MoS2 in the composite increases the number of S atoms on the basal planes, which are inactive for H2 evolution, and hence results in decreased photocatalytic activity. The results discussed in this work may pave the approach for the design and development of ZnO based multifunctional materials for diverse photocatalytic applications. 相似文献
75.
76.
Venkatachalam P. Gunasekaran N. Raghavan K. 《Antennas and Propagation, IEEE Transactions on》1985,33(6):660-662
The corrugated conical horn is considered to be an ideal feed for low sidelobe reflector antennas because of its unique characteristics. Analysis is carried out to show that low flare horns are preferred over high flare horns to give rise to low sidelobe performance for a given offset reflector antenna system. 相似文献
77.
Dynamic analysis for free vibration characteristics of multi-cell structures by using the simplified grillage technique is described. The problems, such as adequate representation of shear lag effects and the torsional stiffness of the closed cells, are discussed. A comparison of the results obtained, for structures with different support conditions, with those obtained by the finite element method establishes the accuracy of the proposed method. The effect of the aspect ratio of the multi-cell structures on their natural frequencies is also investigated. 相似文献
78.
79.
MP Shanmugam P De Potter L Gopal J Biswas MP Bhende 《Canadian Metallurgical Quarterly》1997,45(3):143-161
The management of intraocular tumours has come a long way since the days when enucleation was the only modality of treatment available to the ophthalmologist. Despite the fact that enucleation is still necessary in certain situations, the emphasis is currently on conservative management, thereby saving the eye and some amount of useful vision wherever possible. This review highlights the current trends in the management of adult intraocular tumours with emphasis on newer diagnostic modalities such as computed tomography, magnetic resonance imaging, and fine needle aspiration biopsy. Only those tumours that are most likely to be seen in clinical practice are included. 相似文献
80.