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81.
本文重点针对清洁生产在环境影响评价中的应用进行了详细的分析,以供参考.  相似文献   
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83.
A series of experiments on a solid feed system was performed to investigate the effect of negative pressure gradient on the gas-solid flow pattern and hydrodynamic characteristics.Based on the non-fluidized gas-solid two phase flow and particulate mechanics in the standpipe,a method for predicting the pressure of the air passing through the recycle chamber and the pressure drop through the loop seal slit in these systems is also presented.The predicted pressure profile along the negative pressure gradient from the proposed model exhibits a good agreement with the experimental data.The experimental data show that the gas flow in the standpipe is always upward in the negative pressure gradients,while the direction ofthe superficial gas velocity through the recycle chamber of the loop seal does not affect the pressure drop in standpipe.It increases with an increasing negative pressure gradient.  相似文献   
84.
Chemoradiation-induced mucositis is a debilitating condition of the gastrointestinal tract eventuating from antineoplastic treatment. It is believed to occur primarily due to oxidative stress mechanisms, which generate Reactive Oxygen Species (ROS). The aim of this scoping review was to assess the role of oxidative stress in the development of Oral Mucositis (OM). Studies from the literature, published in MEDLINE and SCOPUS, that evaluated the oxidative stress pathways or antioxidant interventions for OM, were retrieved to elucidate the current understanding of their relationship. Studies failing inclusion criteria were excluded, and those suitable underwent data extraction, using a predefined data extraction table. Eighty-nine articles fulfilled criteria, and these were sub-stratified into models of study (in vitro, in vivo, or clinical) for evaluation. Thirty-five clinical studies evaluated antioxidant interventions on OM’s severity, duration, and pain, amongst other attributes. A number of clinical studies sought to elucidate the protective or therapeutic effects of compounds that had been pre-determined to have antioxidant properties, without directly assessing oxidative stress parameters (these were deemed “indirect evidence”). Forty-seven in vivo studies assessed the capacity of various compounds to prevent OM. Findings were mostly consistent, reporting reduced OM severity associated with a reduction in ROS, malondialdehyde (MDA), myeloperoxidase (MPO), but higher glutathione (GSH) and superoxide dismutase (SOD) activity or expression. Twenty-one in vitro studies assessed potential OM therapeutic interventions. The majority demonstrated successful a reduction in ROS, and in select studies, secondary molecules were assessed to identify the mechanism. In summary, this review highlighted numerous oxidative stress pathways involved in OM pathogenesis, which may inform the development of novel therapeutic targets.  相似文献   
85.
横穿混凝土后浇带配筋对后浇带效能不利影响的计算分析   总被引:3,自引:0,他引:3  
对横穿混凝土后浇带钢筋对后浇带效能的不利影响进行了详细分析,给出了导致后浇带失效的横穿钢筋最大配筋率sρ,max及应用实例,提出了相应的实用设计建议。如建议近似在0~0.5ρs,max范围内控制横穿后浇带的设计配筋;对横穿后浇带的钢筋尽可能采用搭接连接方式等。  相似文献   
86.
As promising anodes for sodium-ion batteries, metal sulfides ubiquitously suffer from low-rate and high-plateau issues, greatly hindering their application in f...  相似文献   
87.
Analysis of an in-plane micro-generator with various microcoil shapes   总被引:1,自引:1,他引:0  
This study presents an analysis of an in-plane micro-generator with various microcoil shapes and multiple aspects of coupling, and reports the fabrication of a prototype micro-generator. It is important to establish analytical solutions for the micro-generator to predict the induced voltage. These analytical solutions can be used to estimate the micro-generator power to reduce the experimental time and the cost. Understanding the physical meanings of the variables can optimize the structure of the micro-electromagnetic generator. This model considers electromagnetism, kinematics, and geometry. The proposed in-plane rotary electromagnetic micro-generator was fabricated using low-temperature co-fired ceramic technology to co-fire the silver microcoils on the ceramic substrate with different shaped coils (e.g., square-shaped, circle-shaped and sector-shaped) both with the printing linewidth and 100 μm spacing of these microcoils. A planar permanent magnet with an outer diameter of 9 mm and a thickness of 700 μm was sintered by Nd/Fe/B. Its residual induction is 1.4 T. The experimental data in this study can be compared with analytical solutions. Analytical results show that the micro-generator with a sector-shaped microcoil generates a maximum effective value of 218.127 mV induced voltage at 1395.34 rad/s. Experimental measurements show a close agreement with these analytical solutions.  相似文献   
88.
89.
In an optical network, the connections are generally bidirectional, but their QoS parameters in each direction may be not the same. In this paper, we propose an enhanced algorithm called Node Label Order First (NLOF), which can maintain asymmetrical information and guarantee availability of the compressed topology. Besides, a decoding algorithm to restore the compressed topology named Average Proportional point (AP) is also proposed, which not only retains the space complexity of the aggregation process but also improves the accuracy of the restored information. Simulation results show that combing NLOF with AP can balance the contradiction between space complexity of the aggregation algorithm and routing accuracy.  相似文献   
90.
To keep up with the trend of integrating more functionality within lighter and smaller consumer electronics devices, the dimensions of components keep shrinking. Technologies such as high density interconnection, 3-D interconnection, system in package (SIP), and flexible circuit are becoming more commonly used. The smaller dimensions of the conductors and insulators (spacing) used in these technologies make them more sensitive to chemical contamination. Trace amounts of chemical contamination introduced during the manufacturing process or in the field can cause device failures. The failure mechanisms include inversion-induced leakage current, corrosion, and electro-chemical migration, to name a few. The complexity of materials used in a highly integrated system also poses new challenges for fault isolation and chemical characterization in failure analysis. This paper calls attention to the selection of appropriate analytical techniques in terms of spatial resolution and sensitivity, sample preparation complexity, throughput, and detection limitations. We present two failure analysis cases in which LA-ICP MS, in conjunction with other analytical techniques, was successfully used to identify the source of chemical contamination and the root cause.  相似文献   
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