离子液体中纤维素的溶解及再生特性

探讨了不同来源纤维素在离子液体1-丁基-3-甲基咪唑氯代盐(［bmim］Cl)中的溶解性能,并采用红外光谱、X-射线衍射及热重分析等手段对木浆纤维素在离子液体［bmim］Cl中溶解和再生前后的结构变化进行了分析。结果表明,未经活化的纤维素可直接溶解于离子液体［bmim］Cl 而不发生其它衍生化反应,原纤维素聚合度越低,溶解越容易。再生纤维素分子量较原纤维素有所降低,结晶状态由纤维素Ⅰ转变为纤维素Ⅱ,再生后纤维素热分解温度降低,热稳定性略有下降。     

基于Skype API的视频监控系统的设计与实现

近年来,视频监控系统在安全防范、信息获取、指挥调度等领域内获得越来越广泛的应用.本文提出了一种针对于诸如家庭、人员职守、设备状况等情况进行监控的实现方案,通过对Skype VoIP平台的API集成,在监控现场的微机上只需安装一个USB摄像头即可实现监控,该系统可支持远程用户对实时监控图像的观看,以及基于即时通信的监控端控制,具备了智能性、灵活性和可伸缩性.     

实际伽利略搜救信号参数估计的Cramer-Rao界

考虑调制不对称度和信息位宽的不确定度,研究了实际伽利略搜救信号信息位宽、到达频率(FOA)、到达时间(TOA)估计的Cramer-Rao界(CRB).推导了伽利略搜救信号Fisher信息矩阵中各元素的计算表达式,利用单位冲激函数的性质和Parseval定理,将单位冲激函数的平方和转换到频域进行计算,得到了信息位宽、FOA和TOA估计的CRB的解析结果.数值分析和Monte Carlo仿真结果表明,CRB具有有效性,可以用于评估上述参数估计算法的性能.     

基于模糊梯度的微齿轮图像边缘检测算法

提出一种基于模糊梯度思想的微齿轮图像边缘检测算法.该算法采用正切归一化函数对灰度图像模糊化,并计算该模糊图像的梯度矩阵;采用正弦函数对梯度矩阵进一步模糊化得到模糊梯度矩阵;采用基于归一化实数编码的遗传算法来搜索最优的阈值λ对模糊梯度矩阵做截集,获取图像边缘点集合.实验中以不同微齿轮图像作为实验对象,测试了该算法性能.实验结果表明,该算法的检测精度优于10μs,检测时间基本为1s,整体性能优于Canny算法和Pal-King算法.     

螺旋锥齿轮切齿调整参数的精确反调

针对螺旋锥齿轮齿形误差难以精确修正的问题,在国产3906型齿轮测量中心上,采用坐标测量法获得了螺旋锥齿轮的齿面形状;提出进行齿深控制的锥齿轮测量齿面切齿调整参数非线性最小二乘优化反调方法,并建立了反调优化的数学模型;采用该方法对磨齿后的某弧齿锥齿轮小轮进行反调计算,结果表明该方法能较为精确地获取锥齿轮副的切齿调整参数.     

油橄榄资源及育种研究现状

油橄榄是世界重要的经济作物,其果实既可以食用也可以榨取橄榄油.油橄榄原产地中海地区,现已在世界各地广泛种植.就其近年来国际上有关油橄榄传粉和坐果、品种鉴定的新途径,特别在育种技术方面的研究现状作一概述.     

4-二甲氨基吡啶类离子液体的合成、表征及性质研究

以4-二甲氨基吡啶为原料,经烷基化后得到2种吡啶盐中间体,通过阴离子交换法制备了6种吡啶类离子化合物,其中5种为离子液体,用1H NMR、IR、TG、DSC进行分析和表征,同时考察了6种物质的吸水性和溶解性.结果表明,离子液体的热分解温度均在300℃以上,置于空气中会微量吸水,极易溶于极性溶剂,不溶或微溶于极性小的溶剂.     

关于次微分convexificator与exhauster关系的一个结果

从次微分convexificator和exhauster的概念出发,在局部Lipschitz条件下,应用函数的上凸(下凹)逼近的exhaustive族存在性定理,并结合已有的相关结论,得出必存在上exhauster和上半正则convexificator,分别记为E*h和坠*f(x),使得坠*f(x)∈E*h.     

Photonic integrated technology for multi-wavelength laser emission

We summarized the design, fabrication challenges and important technologies for multi-wavelength laser transmitting photonic integration. Technologies discussed include multi-wavelength laser arrays, monolithic integration and modularizing coupling and packaging. Fabrication technique requirements have significantly declined with the rise of reconstruction-equivalent-chirp and second nanoimprint mask technologies. The monolithic integration problem between active and passive waveguides can be overcome with Butt-joint and InP array waveguide grating technologies. The dynamic characteristics of multi-factors will be simultaneously measured with multi-port analyzing modules. The performance of photonic integration chips is significantly improved with the autoecious factors compensation packaging technique.     

Phase field simulation of interatomic potentials for double phase competition during early stage precipitation

Phase field model was employed to study the variations of interatomic potentials of Ni 3 Al (L1 2 phase) and Ni 3 V (DO 22 phase) as a function of temperature and concentration. The long-range order (LRO) parameter related interatomic potentials equations formulated by Khachaturyan were utilized to establish the inversion equations for L1 2 and DO 22 phases, with which interatomic potentials could be calculated. The interatomic potentials of Ni-Al and Ni-V exhibited approximately linear increases and decreases, individually, with enhanced Al concentration. Substituting the inverted interatomic potentials into the microscopic phase field equations led to three cases of precipitation sequence: the DO 22 phase preceded L1 2 phase precipitating at the interatomic potentials of Ni-V > Ni-Al; the vice cases; and two phases precipitated simultaneously at interatomic potentials of Ni-V and Ni-Al were equal.