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Anaerobic digestion improvement can be accomplished by different methods. Besides optimization of the process conditions, pretreatment of input sludge and increase of process temperature is frequently used. The thermophilic process brings a higher solids reduction and biogas production, a high resistance to foaming, no problems with odour, better pathogens destruction and an improvement of the energy balance of the whole treatment plant. Disintegration of excess activated sludge in a lysate centrifuge was proved to cause increase of biogas production in full-scale conditions. The rapid thermal conditioning of digested sludge is an acceptable method of particulate matter disintegration and solubilization. 相似文献
23.
N. Jayaprakash N. Kalaiselvi C. H. Doh Gangulibabu D. Bhuvaneswari 《Journal of Applied Electrochemistry》2010,40(12):2193-2202
A series of LiM1xM2yMn2−x−yO3.8F0.2 (M1 = Cr, M2 = V; x = y = 0.2) cathodes, viz., LiMn2O3.8F0.2, LiCr0.2Mn1.8O3.8F0.2 and LiCr0.2V0.2Mn1.6O3.8F0.2 along with native LiMn2O4 have been synthesized by Citric Acid assisted Modified (CAM) sol–gel method, with a view to understand the effect of synthesis
methodology and the effect of dual category dopants, viz., anion and/or cation upon spinel cathodes individually. An acceptable
capacity retention (94%) observed up to 50 cycles for native LiMn2O4 cathodes is attributed to the significance of CAM sol–gel method. Similarly, the encouraging charge–discharge results of
LiMn2O3.8F0.2 (130 mAh g−1) and LiCr0.2Mn1.8O3.8F0.2 (142 mAh g−1) cathodes revealed a possible augmentation in the reversible capacity behavior of the spinels upon F− substitution at 32e site and the simultaneous substitution of Cr3+ and F− at 16d and 32e sites respectively. 相似文献
24.
M. Prekajski Z. Dohčević-Mitrović M. Radović B. Babić J. Pantić A. Kremenović B. Matović 《Journal of the European Ceramic Society》2012,32(9):1983-1987
Nanocrystalline powders of solid solution CeO2–Bi2O3 were synthesized by self-propagating room temperature reaction (SPRT) procedure with composition (Ce1?xBixO2?δ where the x = 0.1–0.5). X-ray diffraction analyses show that for x < 0.50 a solid solution with fluorite structure is formed. Rietveld's structure refinement method was applied to characterize prepared powders and its microstructure (size–strain). The lattice parameters increase according to Vegard's rule with increasing of Bi concentration. The average crystallite size is about 2–3 nm. Spectroscopic ellipsometry and Raman scattering measurements were used to characterize the samples at room temperature. The Raman measurements demonstrated electron molecular vibrational coupling and increase of oxygen vacancy concentration whereas increase of Bi content provokes a small decrease of optical absorption edge in comparison with pure ceria. Specific surface area of obtained powders was measured by Brunauer–Emmet–Teller (BET) method. 相似文献
25.
While various types of capital have been identified and studied as drivers of economic development, recent arguments surrounding social capital in particular have led to calls for greater attention to its role in economic development within a country. Thus, we examine social capital relative to its impact on economic development at the country level. We employ a generalized social capital index (based on measures of trust, associational activities, and civic norms) to test hypotheses suggesting a positive relationship between social capital and economic development, while also considering the impact of social capital on entrepreneurship and on human capital as intermediary effects on economic development. In general, we examine the relationship between core constructs of social capital and economic development within and across 47 selected countries. Findings reveal strong support for the hypothesized relationships, with important implications for policy direction and future research. 相似文献
26.
Young-Hee Kim Jae-Yoon Sim Hong June Park Jae-Ik Doh Kun-Woo Park Hyun-Woong Chung Jong-Hoon Oh Choon-Sik Oh Seung-Han Ahn 《Solid-State Circuits, IEEE Journal of》1997,32(1):79-85
The occasional power-on latch-up phenomenon of DRAM modules with a data bus shared by multiple DRAM chips on different modules was investigated and the circuit techniques for latch-up prevention were presented. Through HSPICE simulations and measurements, the latch-up triggering source was identified-to be the excessive voltage drop at the n-well pick-up of the CMOS transmission gate of read data latch circuit due to the short-circuit current which flows when the bus contention occurs during power-on. By extracting the HSPICE Gummel-Poon model parameters of the parasitic bipolar transistors of DRAM chips from the measured I-V and C-V data, HSPICE simulations were performed for the power-on latch-up phenomenon of DRAM chips. Good agreements were achieved between measured and simulated voltage waveforms. In order to prevent the power-on latch-up even when the control signals (RAS, GAS) do not track with the power supply, two circuit techniques were presented to solve the problem. One is to replace the CMOS transmission gate by a CMOS tristate inverter in the DRAM chip design and the other is to start the CAS-BEPORE-RAS (CBR) refresh cycle during power-on and thus disable all the Dout buffers of DRAM chips during the initial power-on period 相似文献
27.
Influence of Shell Thickness on the Performance of Light‐Emitting Devices Based on CdSe/Zn1‐XCdXS Core/Shell Heterostructured Quantum Dots 下载免费PDF全文
28.
In-Jin Shon Dong-Mok LeeJung-Mann Doh Jin-Kook YoonIn-Yong Ko 《Materials Science and Engineering: A》2011,528(3):1212-1215
A dense nanostructured MoSi2-SiC-Si3N4 composite was sintered by the high frequency induction heating method within 2 min from mechanically activated powder of Mo2N, Mo2C and Si. Highly dense MoSi2-SiC-Si3N4 composite was produced under simultaneous application of a 80 MPa pressure and the induced current. Mechanical properties and grain size of the composite were investigated. The average hardness and fracture toughness values obtained were 1420 kg/mm2 and 4.5 MPa m1/2, respectively. 相似文献
29.
O Dohán W H?ppner F Salamon M Góth L Kovács G Szilágyi I Szabolcs 《Canadian Metallurgical Quarterly》1998,139(52):3117-3120
The first Hungarian MEN IIB (multiplex endocrine neoplasia) syndrome is reported with the short summary of the literature about the pathogenesis and diagnosis of medullary thyroid carcinoma, presenting 80% in sporadic, 20% in hereditary form. The appearance of the patients alone (marfanoid stature, bulky lips, and ganglioneuromatosis of the tongue) may be almost enough for the presumption for the diagnosis of MEN IIB: For screening and preventing the clinical manifestation of the very aggressive medullary carcinoma in the relatives of the patient, the genetic screening is indispensable. The costs of the genetic screening and early treatment of the patients are much lower than the expenses of the traditional annual biochemical screening and the--delayed, often only supportive--treatment of the clinically manifested illness. 相似文献
30.
Colloidal nickel (Ni) nanocrystals were used to direct the synthesis of crystalline silicon (Si) nanowires in an organic solvent. The reaction temperatures ranged from 400 degrees C to 520 degrees C with pressures from 14.3 to 23.4 MPa, conditions that are well above the critical point of the solvent. The Ni nanocrystals play two roles in the synthesis: (1) Ni catalyzes the decomposition of the silicon precursors, i.e., arylsilanes, alkylsilanes, and trisilane, to silicon; (2) Ni nanocrystals induce silicon crystallization through the solid-phase alloying of Si in the Ni seeds. We call this nanowire growth mechanism supercritical fluid-solid-solid (SFSS) synthesis. 相似文献