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The health monitoring has been studied to ensure integrity of design of engine structure by detection, quantification, and prediction of damages. Early detection of faults may allow the downtime of maintenance to be rescheduled, thus preventing sudden shutdown of machines. In cylinder pressure developed, vibrations and noise emissions data provide a rich source of information about condition of engines. Monitoring of vibrations and noise emissions are novel non-intrusive methodologies for which positioning of various transducers are important issue. The presented work shows applicability of these diagnosis methodologies adopted in case of diesel engines. The effects of changing various fuel injection parameters was analyzed. Scope of using non-intrusive technique has been analyzed by changing locations of microphone. Novelty of this worklies in exploring signal processing methods for various locations around the engine test set up. Various frequency ranges of contributing noise and vibration sources were identified. Time-Frequency analysis showed the onset of various cyclic. Based on the identification of various frequency bands, it is possible to device suitable filters in order to extract more information. 相似文献
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Synthesis,spectral investigation and development of tetrahedral copper(II) complexes as artificial metallonucleases and antimalarial agents 下载免费PDF全文
Seven new copper(II) complexes of type [Cu(A)(L)]?H2O (A = sparfloxacin, ciprofloxacin, levofloxacin, gatifloxacin, pefloxacin, ofloxacin, norfloxacin; L = 5‐[(3‐chlorophenyl)diazenyl]‐4‐hydroxy‐1,3‐thiazole‐2(3H)‐thione) were synthesized and characterized using elemental and thermogravimetric analyses, and electronic, electron paramagnetic resonance (EPR), Fourier transform infrared and liquid chromatography–mass spectroscopies. Tetrahedral geometry around copper is assigned in all complexes using EPR and electronic spectral analyses. All complexes were investigated for their interaction with herring sperm DNA utilizing absorption titration (Kb = 1.27–3.13 × 105 M?1) and hydrodynamic volume measurement studies. The studies suggest the classical intercalative mode of DNA binding. The cleavage reaction on pUC19 DNA was monitored by agarose gel electrophoresis. The results indicate that the Cu(II) complexes can more effectively promote the cleavage of plasmid DNA. The superoxide dismutase mimic activity of the complexes was evaluated by nitroblue tetrazolium assay, and the complexes catalysed the dismutation of superoxide at pH = 7.8 with IC50 values in the range 0.597–0.900 μM. The complexes were screened for their in vitro antibacterial activity against five pathogenic bacteria. All the complexes are good cytotoxic agents and show LC50 values ranging from 5.559 to 11.912 µg ml?1. All newly synthesized Cu(II) complexes were also evaluated for their in vitro antimalarial activity against Plasmodium falciparum strain (IC50 = 0.62–2.0 µg ml?1). Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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上海秀派公司坚持自己的技术长项——2.45GHz有源RFID,充分发扬该种RFID的特长,记者采访该公司时了解到了开发方面的很多细节、成功案例和实施经验。我们不但非常推崇该公司的“锲而不舍”的意志,而且还意识到如果秀派公司的成功经验一旦辐射到中国的RFID行业中,一定会把这项在国外诞生的技术更好地植根于中国的土壤,使之更加适合中国的实用环境。 相似文献
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集成电路生产中废气的污染及治理 总被引:1,自引:1,他引:0
介绍集成电路生产中产生各种废气的种类,废气中有害物质浓度及其危害性,并依据工程实践,评述了各类有害废气的各种处理方法。 相似文献
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该文对中国与世界IC产业的发展进行了历史回顾,重点阐述了产业现状与发展方向,并对新世纪的前景进行了科学预测。 相似文献
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本文提出了一个深亚微米条件下的多层VLSMCM有约束分层层分配的遗传算法。该算法分为两步:首先进行超层分配,使各线网满足Crosstalk约束,且超层数目最少;然后进行各超层的通孔最少化二分层。与目前的层分配算法相比,该遗传算法具有目标全面,全局优化能力强等特点,是一种可应用于深亚微米条件下的IC CAD的有效分层方法。 相似文献
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