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排序方式: 共有1223条查询结果,搜索用时 15 毫秒
1.
Soumya Ghosh Chowdhury Jagannath Chanda Sreedip Ghosh Koushik Banerjee Shib Shankar Banerjee Amit Das Prasenjit Ghosh Sanjay Kr. Bhattacharyya Rabindra Mukhopadhyay 《Polymer Engineering and Science》2020,60(8):1973-1983
Proficiency on underlying mechanism of rubber-metal adhesion has been increased significantly in the last few decades. Researchers have investigated the effect of various ingredients, such as hexamethoxymethyl melamine, resorcinol, cobalt stearate, and silica, on rubber-metal interface. The role of each ingredient on rubber-metal interfacial adhesion is still a subject of scrutiny. In this article, a typical belt skim compound of truck radial tire is selected and the effect of each adhesive ingredient on adhesion strength is explored. Out of these ingredients, the effect of cobalt stearate is found noteworthy. It has improved adhesion strength by 12% (without aging) and by 11% (humid-aged), respectively, over control compound. For detailed understanding of the effect of cobalt stearate on adhesion, scanning electron microscopy and energy dispersive spectroscopy are utilized to ascertain the rubber coverage and distribution of elements. X-ray photoelectron spectroscopy results helped us to understand the impact of CuXS layer depth on rubber-metal adhesion. The depth profile of the CuXS layer was found to be one of the dominant factors of rubber-metal adhesion retention. Thus, this study has made an attempt to find the impact of different adhesive ingredients on the formation of CuXS layer depth at rubber-metal interface and establish a correlation with adhesion strength simultaneously. 相似文献
2.
Khandelia M. Bambha N.K. Bhattacharyya S.S. 《Signal Processing, IEEE Transactions on》2006,54(2):556-569
This paper explores the problem of efficiently ordering interprocessor communication (IPC) operations in statically scheduled multiprocessors for iterative dataflow graphs. In most digital signal processing (DSP) applications, the throughput of the system is significantly affected by communication costs. By explicitly modeling these costs within an effective graph-theoretic analysis framework, we show that ordered transaction schedules can significantly outperform self-timed schedules even when synchronization costs are low. However, we also show that when communication latencies are nonnegligible, finding an optimal transaction order given a static schedule is an NP-complete problem, and that this intractability holds both under iterative and noniterative execution. We develop new heuristics for finding efficient transaction orders, and perform an extensive experimental comparison to gauge the performance of these heuristics. 相似文献
3.
Fabrication and thermal characterization of a resistance temperature detector (RTD) heater and microthermocouples (MTs) on silicon substrates have been reported in this paper. The influence of film thickness and nickel-gold (Au) electroplating on RTD on its steady-state temperature with respect to its steady-state electrical power input and resistance is studied. Further, the thermal effects of multiple thermocouples in a thermopile as well as the effects of Au layers in the contact pads of the thermopiles on their open-circuit Seebeck voltage are studied. Therein lies the novelty of this paper. The in situ operating relationships for the RTD heater and the MT are provided 相似文献
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5.
BJ Bhattacharyya JW Day JE Gundeck S Leonard RL Wollmann CM Gomez 《Canadian Metallurgical Quarterly》1997,27(4):367-377
While the slow onset of desensitization of nicotinic acetylcholine receptors (AChRs), relative to the rate of acetylcholine removal, excludes this kinetic state from shaping synaptic responses in normal neuromuscular transmission, its role in neuromuscular disorders has not been examined. The slow-channel congenital myasthenic syndrome (SCCMS) is a disorder caused by point mutations in the AChR subunit-encoding genes leading to kinetically abnormal (slow) channels, reduced miniature endplate current amplitudes (MEPCs), and degeneration of the postsynaptic membrane. Because of this complicated picture of kinetic and structural change in the neuromuscular junction, it is difficult to assess the importance of the multiple factors that may be responsible for the reduced endplate current amplitudes, and ultimately the clinical syndrome. In order to address this we have used a transgenic mouse model for the SCCMS that has slow AChR ion channels and reduced endplate responsiveness in the absence of any of the degenerative changes. We found that the reduction in MEPC amplitudes in these mice could not be explained by either reduced AChR number or by reduced AChR channel conductance. Rather, we found that the mutant AChRs in situ manifested an activity-dependent reduction in sensitivity that caused diminished MEPC and endplate current amplitude with nerve stimulation. This observation demonstrates that the basis for the reduction in MEPC amplitudes in the SCCMS may be multifactorial. Moreover, these findings demonstrate that, under conditions that alter their rate of desensitization, the kinetic properties of nicotinic AChRs can control the strength of synaptic responses. 相似文献
6.
The medium coking coal fines of − 0.5 mm from Jharia coal field were taken for this investigation. The release analysis of the composite coal reveals that yield is very low at 10.0% ash, about 25% at 14% ash and 50% at 17% ash level. The low yield is caused by the presence of high ash finer fraction. The size-wise ash analysis of − 0.5 mm coal indicated that − 0.5 + 0.15 mm fraction contains less ash than − 0.15 mm fraction. Thus, the composite feed was split into − 0.5 + 0.15 mm and − 0.15 mm fractions and subjected to flotation separately. The low ash bearing fraction (− 0.5 + 0.15 mm) was subjected to two stages collectorless flotation to achieve the concentrate with 10% ash. The cleaner concentrate (18.9%) with 10% ash was recovered which has an application in metallurgical industries. The concentrate of 30.2% yield with 12.5% ash could be achieved in one stage collectorless flotation which is suitable for use in coke making as sweetener. As the − 0.15 mm fraction contains relatively high ash, collector aided flotation using sodium silicate was performed to get a concentrate of 23.6% yield with about 17% ash. The blending of this product with cleaner tail obtained from − 0.5 + 0.15 mm produces about 35.0% yield with 17% ash and that can be utilized for coke making. The reject from the two fractions can be used for conventional thermal power plant or cement industries using a 23.5% ash after one stage collector aided flotation and the final tailings produced content ash of 61.6% can be used for fluidization combustion bed (FBC). This eventually leads to complete utilization of coal. 相似文献
7.
8.
Accurate formulation for the wall admittance of a circular patch on a thick substrate/superstrate is presented. The principle of equivalence is invoked at the physical aperture of the patch, which yields equivalent electric and magnetic surface currents for the outside fields. The unknown electric current, in terms of the aperture electric field, is obtained from the field continuity condition on the aperture surface. Numerical results reveal that for a small substrate thickness, the equivalent electric current may be ignored. It should, however, be included in the analysis for larger substrate thicknesses. Numerical results for the wall conductance, wall susceptance, and radiation efficiency of a patch with various substrates and superstrates are presented 相似文献
9.
Renewable energies are considered as an essential element of any strategy for sustainable energy development. The poor in the developing world without access to modern energies are regarded as a major market for renewable energies. This short paper attempts to analyse whether such a niche is backed by any economic logic and whether renewable energy and the poor nexus could be a strategy for success. The paper suggests that contrary to the common belief, the economic logic behind the niche is unsound and that the nexus is not a recipe for success. 相似文献
10.
SH Thomas JE Horner K Chew J Connolly B Dorani L Bevan S Bhattacharyya MG Bramble KH Han A Rodgers B Sen B Tesfayohannes H Wynne DN Bateman 《Canadian Metallurgical Quarterly》1997,16(9):495-500
1. Paracetamol is increasingly involved in self-poisoning in the United Kingdom and remains a common cause of fatal poisoning. 2. To document the epidemiology and early management of paracetamol poisoning data were collected on consecutive patients with suspected paracetamol poisoning presenting to 6 hospitals in the North East of England over 12 weeks in 1994. 3. There were 400 presentations (attendance rate 1.14/10(3) population/yr) involving 343 persons (45% male). Paracetamol concentrations at 4 h correlated weakly with reported paracetamol dose (R = 0.49, P < 0.0001) and were similar comparing those treated and not treated by gastric decontamination. 4. In 38 (9%) cases paracetamol concentrations were above the appropriate nomogram treatment line, including 3% and 20% of patients who reported ingesting less than and more than 12 g respectively. In 21 patients acetylcysteine treatment was deferred until admission to the ward, the mean delay involved was 2.8 h. 5. One patient died, from arrhythmias caused by co-ingested dothiepin. 6. Paracetamol poisoning is common. Most cases do not have potentially toxic plasma paracetamol concentrations, but those who do often present late and antidotal treatment may be delayed inappropriately. 相似文献