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排序方式: 共有256条查询结果,搜索用时 78 毫秒
41.
A. Singh V. Bajpai M. Srivastava K. R. Arya B. Kumar 《Rapid communications in mass spectrometry : RCM》2014,28(19):2089-2100
42.
Wan Nor Roslam Wan Isahak Siti Zubaidah Hasan Zatil Amali Che Ramli Muneer M. Ba-Abbad Mohd Ambar Yarmo 《Research on Chemical Intermediates》2018,44(2):829-841
Mixed Cu and Mg oxides on nitrogen-rich activated carbon (AC) from Nypha fruticans biomass were characterized and their CO2 adsorption performance was measured. Highly dispersed CuO and MgO nanoparticles on AC was obtained using an ultrasonic-assisted impregnation method. The optimum adsorbent is 5%CuO–25%MgO/AC having good surface properties of high surface area, pores volume and low particles agglomeration. The higher content of MgO of 5%CuO–25%MgO/AC adsorbent contributes to less metal carbide formation which increases their porosity, surface area and surface basicity. XPS analysis showed some amount of nitrogen content on the surface of the adsorbent which increased their surface basicity towards selective CO2 adsorption. The presence of moisture accelerated the CO2 chemisorption to form a hydroxyl layer on the surfaces. The 5%CuO–25%MgO/AC adsorbent successfully adsorbed CO2 via physisorption and chemisorption of 14.8 and 36.2 wt%, respectively. It was significantly higher than fresh AC with better selectivity to CO2. 相似文献
43.
Wireless Personal Communications - The Internet of Things (IoT) is a network formed by smart devices whose core contains embedded technology in order to collect sensory information and exchange it... 相似文献
44.
We report efficient bulk heterojunction solar cells fabricated by inserting a discotic triphenylene derivative into poly (3-hexylthiophene): [6, 6]- phenyl-C61-butyric acid methyl ester. A layer of molybdenum oxide was inserted between anode and active layer. Power conversion efficiency of 2.0% was achieved for these photovoltaic solar cells containing self-organised discotic liquid crystals in the active layer under one sun condition. The influence of varying the thickness of liquid crystal layer and annealing on these solar cells was also studied. Post annealing the bulk heterojunction devices with discotic liquid crystal layer of thickness 20 nm in them yielded an open circuit voltage of 0.41 V, short circuit current density of 17.0 mA cm?2, a Fill factor of 0.35 and power conversion efficiency of 2.5%. 相似文献
45.
Gaurav?Madhu Haripada?BhuniaEmail author Pramod?K.?Bajpai Golok?B.?Nando 《Polymer Science Series A》2016,58(1):57-75
Blends of high density polyethylene/poly(lactic acid) with/without compatibilizer and pro-oxidant (cobalt stearate) were prepared by melt blending technique. In ratio 80/20, the blend revealed a good combination of tensile properties and optimum poly(lactic acid) content. The improvement in mechanical properties of this blend was achieved by addition of 4 phr compatibilizer. Cobalt stearate (CoSt) was added to 80/20 blends in 0.1% and 0.2% (w/w) ratios. The obtained blends were characterized by DSC, SEM, FTIR spectroscopy, rheological study, etc. All the prepared blends were able to biodegrade in composting environment and the blend containing pro-oxidant was maximum degraded. 相似文献
46.
An inhibition effect of PdCl2 on the rate of oxidation of sugars by alkaline hexacyanoferrate(III) has been observed. The order of reactions in hexacyanoferrate(III) and OH− is zero and unity, respectively, while that in sugars decreases from unity at higher sugar concentration. The kinetic data and spectrophotometric evidence support the formation of {PdII − (sugar)} and {PdII − sugar)2} complexes and their resistance to react with Fe(CN)63− © 1996 John Wiley & Sons, Inc. 相似文献
47.
A. P. Gnana Prakash Vinayakprasanna N. Hegde T. M. Pradeep N. Pushpa P. K. Bajpai S. P. Patel 《辐射效应与固体损伤》2017,172(11-12):922-930
The total dose effects of 5?MeV proton and Co-60 gamma irradiation in the dose range from 1 to 100?Mrad on advanced 200?GHz Silicon–Germanium heterojunction bipolar transistors (SiGe HBTs) are investigated. The SRIM simulation study was conducted to understand the energy loss of 5?MeV proton ions in SiGe HBT structure. Pre- and post-radiation DC figure of merits such as forward- and inverse-mode Gummel characteristics, excess base current, DC current gain and output characteristics were used to quantify the radiation tolerance of the devices. The results show that the proton creates a significant amount of damages in the surface and bulk of the transistor when compared with gamma irradiation. The SiGe HBTs shows robust ionizing radiation tolerance even up to a total dose of 100?Mrad for both radiations. 相似文献
48.
Anamika Bajpai Kashi Nath Prasad Priyanka Mishra Rakesh Kumar Gupta Aloukick K. Singh Bal Krishna Ojha 《Magnetic resonance imaging》2014
Background and purpose
Proton magnetic resonance spectroscopy (PMRS) has high sensitivity and specificity for the detection of pyogenic brain abscess and the categorization of bacteria. But the metabolite patterns failed to evaluate the etiology of disease when the culture results are sterile. The aim of the present study is to compare the multimodality techniques viz., conventional culture, MR spectroscopy and 16S rRNA PCR and sequencing for rapid diagnosis of etiology in brain abscess and evaluate the PMRS in culture sterile samples and also demonstrate the sensitivity and specificity of these techniques.Methods
Thirty five patients underwent MRI on a 3 T MRI and in-vivo PMRS for the diagnosis and evaluation of various resonances of metabolites such as lipid (LIP), lactate (LAC), acetate (AC), amino acid (AC), succinate (SUC). Pus was collected for identification of etiologic agents by culture and molecular method.Results
In 35 samples, metabolite patterns were as follows: LIP/LAC/AA, n = 17, LIP/LAC/AA/SUC with or without AC, n = 17 and LIP/LAC/AA/AC, n = 1. Culture showed bacterial growth in 22 samples (18 aerobic/facultative anaerobic, 9 anaerobic) whereas molecular method was detected 26 aerobic/facultative anaerobic, 13 anaerobic, 4 microaerophilic bacteria. Among the 13 sterile samples, molecular method detected 16 microorganisms along with 3 mixed infections and PMRS recognized metabolite patterns as LIP/LAC/AA, n = 5 and LIP/LAC/AA/SUC with or without AC, n = 8. The sensitivity of in-vivo PMRS in sterile samples was 100% and 75%, and specificity was 75% and 100% for aerobic and anaerobic organisms respectively.Conclusion
Based on metabolite resonances, PMRS can detect slow growing and fastidious organisms and classify them into aerobic and anaerobic bacteria which are difficult to culture by conventional method. It can categorize microorganisms even in culture sterile samples with rational sensitivity and specificity which may allow early choice of targeted therapy. 相似文献49.
Solution-mixed poly(methyl methacrylate) (PMMA): poly(vinylidene fluoride) (PVDF) polyblends with different weight percentage ratios were irradiated with various doses of gamma irradiation (1–100 Mrad). The effect of irradiation on the strength of blend specimens was studied by measuring the surface microhardness using a Vickers microhardness tester attached to a Carl Zeiss NU-2 Universal research microscope. The irradiation was found to produce hardening in the blend specimens; however, the degree of hardening depends upon the dose level, testing conditions and also on the miscibility of PMMA and PVDF in the blend specimens. The increase and decrease in microhardness has been explained on the basis of crosslinking and scissioning. The two limits of irradiation dose were 1 and 75 Mrad where significant changes in mechanical strength were observed. 相似文献
50.
Ambar N. Sengupta 《Journal of Geometry and Physics》2003,47(4):398-426
We prove that integration over the moduli space of flat connections can be obtained as a limit of integration with respect to the Yang–Mills measure defined in terms of the heat-kernel for the gauge group. In doing this we also give a rigorous proof of Witten’s formula for the symplectic volume of the moduli space of flat connections. Our proof uses an elementary identity connecting determinants of matrices along with a careful accounting of certain dense subsets of full measure in the moduli space. 相似文献