ANSYS在脉冲CO_2激光对K9玻璃损伤过程模拟中的应用研究

从脉冲CO2激光损伤K9玻璃有限元模型的建立和网格划分、脉冲激光的加载、设置初始条件和边界条件等几个方面,分析了基于ANSYS的脉冲CO2激光损伤K9玻璃模拟过程中的一些关键问题,建立了脉冲CO2激光损伤K9玻璃的有限元模型,对K9玻璃受到脉冲CO2激光辐照时的温度和应力分布进行了数值分析.     

IP网络业务联合认证技术 第1讲IP网络业务安全认证系统发展现状及相关问题分析

IP网络天然的不安全性促使IP网络业务提供者采用各种安全认证技术来保证其所提供的业务的安全性。本文主要介绍IP网络业务安全认证系统发展情况及存在的相关问题。     

准分子激光器异步感应密封传动技术

一种新型准分子激光器循环系统中的密封传动技术，具有可耐高气压，不失耦，不使用昂贵强磁材料，结构简单等优点，虽有涡流损失过大之不足，但能很好地适用于小功率下运行。     

基于数字图像处理技术的集成块姿态检测

基于数字图像处理技术,研究了工业目标检测中集成块的定位和姿态检测方法。先通过对目标图像的预处理和阂值分割完成图像的前期处理,然后通过面积法实现了集成块管脚的定位和检测,再用中心点斜率法完成了对集成块姿态的检测。     

适用于低频率生理信号片上谱分析的低功耗数字芯片设计

本文针对人体传感网络的应用定制设计了一款基于片上处理技术的低功耗的数字芯片。该数字芯片主要包括一个用于生物医学信号谱分析的可扩展FFT处理模块,一个授权的ARM7TDMI内核和其他外围IP模块。该FFT采用了一种新的混合结构,存储器优化,减少乘法器,高效率的地址产生技术来降低功耗。芯片经过流片,并实际测试后表明,性能方面能满足生物医学信号处理要求,功耗方面,在1.8v输入下,功耗仅0.69mW @ 1MHz,该芯片计算256点FFT的能量是基于ARM7嵌入式平台计算所耗功耗的0.9%,同时,与业界主流ASIC实现的FFT相比,也具有低功耗优势。     

Numerical Solutions of the Integral Equation for Excitation-Transmission-Radiation of the Beam Waveguide

The numerical method of the Integral Equation has been used to model the electromagnetic excitation, transmission, and radiation problems of the beam waveguide. The Mode Matching Method has been used to describe the impedance matching situation at the exciting aperture of the waveguide. The excitation conditions were established based on the expansion of the waveguide modes and the continuity of the tangential components of the fields. The volume-surface integral equations combined with the equavalence principle have been used to model the wave transmission in the beam waveguide. The numerical solutions of the electromagnetic transmission and aperture radiation of the waveguide have been given by using the Multilevel Fast Multipole Algorithm (MLFMA). It has been demonstrated that the method proposed by this paper is able to provide the efficient and accurate numerical solution for the excitation, propagation and radiation problems of the beam waveguide with arbitrary shape and electrically large size.     

Size‐Transformable Metal–Organic Framework–Derived Nanocarbons for Localized Chemo‐Photothermal Bacterial Ablation and Wound Disinfection

Severe infectious diseases caused by pathogenic bacteria have become urgent threats to global public health. Antibacterial materials with combined chemo‐photothermal therapeutic capabilities possess distinct advantages when compared with many other antibacterial approaches. However, developing simplified and chemically tunable precursors to synthesize such antibacterial nanoagents for rapidly, safely, and synergistically combating pathogenic bacteria remains a huge challenge. Herein, metal–organic framework (MOF)‐derived nanocarbons with near‐infrared (NIR)‐responsive and size‐transformable capabilities are designed to overcome this challenge. The MOF‐derived nanocarbons with chemo‐photothermal bactericidal capabilities are first synthesized, and then coated with a thermoresponsive gel layer to obtain ON–OFF switching capability for bacterial trapping. The fabricated nanocarbons exhibit high photo‐to‐thermal conversion efficiency and fast size transformation from nanodispersions to micrometer aggregations upon NIR irradiation, thus enabling nanocarbons to generate localized massive heat and abundant Zn²⁺ ions for directly disrupting bacterial membrane and intracellular proteins. Furthermore, these nanocarbons not only exhibit a nearly 100% bactericidal ratio at very low dosage, but also possess highly efficient and safe wound disinfection activities, which are comparable to vancomycin. Overall, these proposed novel nanocarbons display robust and localized chemo‐photothermal bactericidal capability and possess great potential to be used as alternative to antibiotics for broad‐spectrum eradication of pathogenic bacteria.     

激光大坝位移实时监测系统研究

本文研究了激光大坝位移实时监测系统的原理,制作了焦距为１０ｍ的菲涅 波反,给出了在５０ｍ距离上的测量结果。     

脉冲激光二极管端面泵浦Nd;YAG棒时变温度场

在脉冲激光二极管(LD)泵浦的激光晶体中存在升降温的时变过程,为解决脉冲LD端面泵浦的激光晶体产生的热效应问题,基于热传导方程,采用特征函数法和常数变异法得到了脉冲超高斯光束端面泵浦Nd∶YAG棒的时变温度场的一般解析表达式.同时定量分析了单脉冲和重复脉冲端面泵浦Nd∶YAG棒的时变温度规律.研究结果表明,重复脉冲端面...     

Stability of Skutterudite Thermoelectric Materials

By multifilling with La, Ba, Ga, Ti, Yb, Ca, Al, and In, the dimensionless figure of merit ZT of filled skutterudites has been improved in this work. ZT reached 0.75 for p-type (La,Ba,Ga,Ti) _x (Fe,Co)₄Sb₁₂ (x = 0.8 to 1.0) and 1.0 for n-type (Yb,Ca,Al,Ga,In) _y (Co,Fe)₄Sb₁₂ (y = 0.7 to 0.9). After annealing at 873 K for 180 h, 300 h, 710 h, 1000 h, and 5000 h in vacuum, the Seebeck coefficient S and the electrical resistivity ρ of the samples increased while the thermal conductivity λ decreased with increasing annealing time. As a result, the ZT values of both p- and n-type skutterudites remained unchanged or were slightly improved, demonstrating the excellent thermal stability of these skutterudites.