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31.
介绍了某机载电子吊舱的抗振动、抗冲击设计方法。通过合理设计舱体骨架,并对分系统进行加固设计来提高某机载电子吊舱的机械环境适应能力。  相似文献   
32.
集成电路工艺模拟软件SSUPREM4的校验   总被引:1,自引:0,他引:1  
本文对知名的集成电路工艺模拟软件SSUPREM4进行了较仔细的校验,用SSUPREM4模拟了氧化、扩散工艺,并同实验值进行了比较,模拟值和实验值的偏差在10%以内,与集成电路器件模拟软件S-PISCES联用校验了SSUPREM4的工序模拟结果,校验结果有较大参考价值。  相似文献   
33.
The mechanism and properties of infrared absorption of α-helix protein molecules are studied by a theory of bio-energy transport established on the basis of molecular structure. From the vibrational energy-spectra of molecules obtained from this theory we know that the infrared lights with wavelengths of 2 µm ?7 µm can be absorbed by α-helix protein molecules. This is basically consistent with experimental data of infrared absorption of collagen and hemoglobin and bivine serum albumen (BSA) proteins with α-helix structure. From these results we account further for the mechanism and properties of biological effect of infrared lights absorbed by the living systems, i.e., the energy of infrared lights is directly absorbed by the amide-Is in amino acid residues in the protein molecules, which results in vibration of amide-1 and change of conformation of proteins and transport of bio-energy from one place to other along the protein molecular chains in human beings and animals. This is a kind of non-thermally biological effect.  相似文献   
34.
In this paper, a blind signal separation (BSS) methodology for simultaneously received multisystem frequency-overlapped signals in a single-channel (SC) electromagnetic surveillance system is proposed using fast independent component analysis (FastICA) in a dynamical embedding (DE) framework. Firstly, an appropriate DE matrix is constructed out of a series of delay vectors from the SC recording. The lag-time and the dimensional of embedding matrix setting principal are introduced in details. Next, multiple independent components (ICs) are calculated by decomposing the embedding matrix through FastICA algorithm, and ICs can be regarded as a convenient expansion basis of the original signals. Then, these ICs are projected back into the measurement space. After that, these projected ICs are classified and used for recovering the sources of interest based on their independent nature and their power density spectrum. Numerical simulation results obtained in evaluating the proposed methodology’s performance confirmed the effectiveness of the proposed algorithm.  相似文献   
35.
宫娜  汪金辉  郭宝增  庞娇 《半导体学报》2008,29(12):2364-2371
考虑到温度和工艺参数浮动的影响,对休眠双阈值footed多米诺电路的漏电流特性进行了系统的量化研究和比较,得到了不同温度下的最佳休眠状态.基于65和45nm BSIM4模型的HSPICE仿真表明:与业已提出的CHIL(时钟为高,输入均为低电平)状态和CHIH(时钟和输入均为高电平)状态相比,本文提出的CLIL(时钟和输入均为低电平)状态更有利于减小低温下电路的漏电流和高温下的多扇入电路的漏电流.而且,分析了工艺参数的浮动对双阈值footed多米诺电路的漏电流特性的影响,并给出了温度和工艺参数浮动下,双阈值footed多米诺电路漏电流最小的休眠状态.  相似文献   
36.
Thermal characterization provides data on the thermal performance of electronic components under given cooling conditions. The most common thermal characterization parameter used to characterize the behavior of electronic components is the thermal resistance. In this work, experiments are conducted to obtain thermal characterization data for different chips in a multichip package. Using this data, it is shown that the assumption of a linear temperature rise with input power is valid within the expected range of operation of the electronic module. Secondly, the applicability of a resistance matrix superposition methodology to the packaging structure of an integrated power electronic module is evaluated. The temperatures and the associated uncertainties involved in using the resistance matrix superposition method are compared to those obtained directly by powering all chips. It is shown that for any arbitrary power losses from the chips, the resistance matrix superposition method can predict the temperatures of a multichip package with reasonable accuracy for temperature rise up to 50degC.  相似文献   
37.
介绍了GSMHSCSD技术,及其与GSMphase2数据业务的异同。HSCSD作为从2G系统向3G系统演进的一种过渡方案,能灵活提供高速、多速率数据业务,具有较好的发展前景。  相似文献   
38.
张昌  任恩  庞鑫  李蕾  刘刚 《中国激光》2020,(2):155-162
新兴的光动力抗菌疗法是一种无创激发式治疗手段,主要利用近红外光作为光源,激活富集在病灶部位的光敏剂并产生活性氧自由基,最终实现对目标病菌的杀伤。近年来,随着生物材料与纳米医学技术的发展,小分子光敏剂纳米功能化后其生物兼容性和生物安全性得到优化,量子产率和病灶部位富集率显著提升,在抗菌治疗方面有很大的临床应用前景。本文结合小分子光敏剂纳米化策略方法实例,综述了纳米技术在光动力抗菌疗法的应用和发展。  相似文献   
39.
This paper examines various aspects of SAC (Sn–3.8Ag–0.7Cu wt.%) solder and UBM interactions which may impact interconnection reliability as it scales down. With different solder joint sizes, the dissolution rate of UBM and IMC growth kinetics will be different. Solder bumps on 250, 80 and 40 μm diameter UBM pads were investigated. The effect of solder volume/pad metallization area (V/A) ratio on IMC growth and Ni dissolution was investigated during reflow soldering and solid state isothermal aging. Higher V/A ratio produced thinner and more fragmented IMC morphology in SAC solder/Ni UBM reflow soldering interfacial reaction. Lower V/A ratio produced better defined IMC layer at the Ni UBM interface. When the ratio of V/A is constant, the IMC morphology and growth trend was found to be similar. After 250 h of isothermal aging, the IMC growth rate of the different bump sizes leveled off. No degradation in shear strength was observed in these solder bump after 500 h of isothermal aging.  相似文献   
40.
Nanoscale metal‐organic frameworks (NMOFs) have attracted increasing attention for biomedical applications due to their large specific surface area, good biocompatibility, adjustable structures, and diverse functions. By choosing appropriate metal ions and ligands, NMOFs can be synthesized and regulated to assist the diagnosis and treatment of cancer, acting as imaging agents, drug carriers, and cancer therapeutic agents. This review summarizes the recent advances of NMOFs in synthesis, biocompatibility, imaging, and applications in cancer therapies. Among these, the term “biocompatibility” is used to outline their various biological characteristics, and it is mainly discussed from the aspects of size and surface properties of NMOFs. The imaging section mainly emphasizes the application advantages of NMOFs as imaging agents in magnetic resonance, computed tomography, and fluorescence imaging. The applications of NMOFs in four cancer therapies, including phototherapy, radiotherapy, microwave therapy, and ultrasonic therapy, are addressed, especially for thermal and dynamic therapy. Finally, the prospects and challenges of NMOFs in imaging and cancer therapies are also discussed.  相似文献   
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