医用内窥镜微型摄像模组设计

设计了一种新型医用内窥镜微型摄像模组.该模组采用微型、高分辨率的CMOS图像传感器结合低压差分信号（LVDS）传输技术进行设计,使摄像模组直径缩减至5.0mm,并实现了图像数据的长距离高保真传输.搭建了实验平台对摄像模组的摄像功能进行了测试.结果表明：该模组图像传输距离超过2m,分辨率达到30万像素,对口腔溃疡模拟粘膜病变的识别率高达90％.其图像分辨率高,传输距离长,使其适用于内镜诊断;其直径小,能大大提高病人内镜检查的舒适性,为超细内镜诊断提供了一种极佳的解决方案.     

树突细胞算法在线分析组件的研究

原始树突状细胞算法（DCA）的离线分析过程,将会导致时间差异,从而产生假警报,增加了虚警率,也会导致攻击的成功发生,这对一个人侵检测系统来说是致命的。因此,文中的目的就是在不影响检测精度的前提下提高检测速度。于是文中提出了分片思想的在线分析组件与DCA相集成的方法,即根据抗原采样数量或者时间将一系列已处理的信息分割成为更小的部分,使得每个分片独立地进行实时的、周期性的分析,这样在每个分片内的入侵攻击就能及时地被识别出来。文中给出了DCA在线分析模块的伪代码描述,并且将其应用于SYN端口扫描的检测实验中。结果表明,DCA在线分析模块在不影响检测精度的前提下有效地提高了检测速度。     

SORPTION EQUILIBRIUM OF COPPER BY PARTIALLY-COAGULATED CALCIUM ALGINATE GEL

The sorption equilibrium of dissolved copper by spherical partially-coagulated gels of calcium alginate was investigated in this work. The gels were formed by dispensing a viscous algin (food grade sodium alginate from kelp) solution with a multi-tip dispenser into 0.05 M CaCl₂ solution in a loop fluidized bed reactor. The resultant semi-rigid spherical gels were then transferred to another reactor operated batch wise to absorb dissolved copper at low concentrations (10-40 ppm). When the concentration of the inert neutral salt NaNO₃, added to the reactor fluid was 0.01 M, the amount of copper absorbed was found to be substantially higher than that at 0.1 MNaN0₃. The conventional Langmuir's model based on the concentration of copper in solution yielded different values of conditional stability constant at different ionic strengths in the reactor fluid. However, by defining the copper-binding stability constant on the basis of copper activity in the gel phase with the competition from calcium for metal binding sites taken into account, a unique copper-binding stability constant and a unique calcium-binding stability constant were obtained. The numerical procedure for estimating the activity of copper in the gel fluid was modified from Jang et al. Water Research, 1990, in press).     

Functionalization at the double-bond region of jojoba oil. 8. Chemical binding of jojoba liquid wax to a polymer matrixvia an amine “spacer”

Jojoba wax was chemically bonded to a polymer matrixvia stable C-N covalent bonds. The polymer matrix was prepared by amination of several types of styrene-divinyl benzene or styrene-vinylbenzylchloride-divinylbenzene copolymers with diamines or polyethylene imines (polyamines). The jojoba wax was attached to the aminated polystyrene matrix by reacting an allyl-brominated derivative of jojoba with the matrix to form a C-N bond between the matrix and the jojoba wax. The amount of bound jojoba wax added to the polymer was in the range of 20–70% (w/w), depending on the type of polymer matrix and reaction conditions. The double-bond regions in the jojoba wax bonded to the matrix were preserved, and they were subsequently functionalized by phosphonation and sulfur-chlorination reactions.     

Identification of the state of palladium in various hydrogenation catalysts by XPS

Various commercial supported palladium hydrogenation catalysts were studied by XPS and treated at ambient pressure with hydrogen and air. Unused catalysts exhibit a significant fraction of divalent Pd (oxide) which is reduced by hydrogen treatment at room temperature. Exposure to air in systems with carbonate, alumina, silica or active carbon as support causes the formation of a solid solution of oxygen in Pd characterized by a Pd 3d chemical shift of ca. + 0.4 eV. The absolute binding energy of Pd depends strongly on the matrix, indicating a significant contribution of extra-atomic screening, which prevents a direct comparison of reference samples and supported catalysts. Using the oxidation of CO to CO₂ at 300 K as in situ chemical probe it was confirmed that Pd supported on carbonate, silica and alumina exists in the same metallic state which could be activated for the test reaction irrespective of the variation in XPS binding energies.     

荧光光谱法研究茶碱与血红蛋白的相互作用

运用荧光光谱法研究了茶碱与牛血红蛋白(BHb)的相互作用,茶碱对牛血红蛋白的荧光猝灭过程主要为静态猝灭。测定了不同温度下该反应的结合常数、结合位点数及结合热力学参数,热力学参数的变化,表明上述作用过程是一个熵增加、自由能降低的自发分子间作用过程,而且是以疏水作用为主。用同步荧光技术考察了茶碱对BHb构象的影响。     

浅谈"理论设计模块"教学改革

根据多年的教学经验,就“数控加工”方向的机电专业,浅谈对其“理论设计模块”教学内容和教学方法的改革。     

Interactions between immunoglobulin-like and catalytic modules in Clostridium thermocellum cellulosomal cellobiohydrolase CbhA

Cellobiohydrolase CbhA from Clostridium thermocellum cellulosome is a multi-modular protein composed starting from the N-terminus of a carbohydrate-binding module (CBM) of family 4, an immunoglobulin(Ig)-like module, a catalytic module of family 9 glycoside hydrolases (GH9), X1(1) and X1(2) modules, a CBM of family 3 and a dockerin module. Deletion of the Ig-like module from the Ig-GH9 construct results in complete inactivation of the GH9 module. The crystal structure of the Ig-GH9 module pair reveals the existence of an extensive module interface composed of over 40 amino acid residues of both modules and maintained through a large number of hydrophilic and hydrophobic interactions. To investigate the importance of these interactions between the two modules, we compared the secondary and tertiary structures and thermostabilities of the individual Ig-like and GH9 modules and the Ig-GH9 module pair using both circular dichroism (CD) spectroscopy and differential scanning calorimetry (DSC). Thr230, Asp262 and Asp264 of the Ig-like module are located in the module interface of the Ig-GH9 module pair and are suggested to be important in 'communication' between the modules. These residues were mutated to alanyl residues. The structure, stability and catalytic properties of the native Ig-GH9 and its D264A and T230A/D262A mutants were compared. The results indicate that despite being able to fold relatively independently, the Ig-like and GH9 modules interact and these interactions affect the final fold and stability of each module. Mutations of one or two amino acid residues lead to destabilization and change of the mechanism of thermal unfolding of the polypeptides. The enzymatic properties of native Ig-GH9, D264A and T230A/D262A mutants are similar. The results indicate that inactivation of the GH9 module occurs as a result of multiple structural disturbances finally affecting the topology of the catalytic center.     

基于ADS的毫米波收发组件设计及仿真

接收发射组件(T/R组件)是相控阵天线的核心部分,在通信、雷达等应用领域日益得到重视。针对毫米波段的T/R组件进行了研究,在相控阵技术基本原理分析基础上,对功放、低噪放、移相、衰减、开关及中频放大等模块进行了选型设计,利用安捷伦ADS软件对T/R组件进行仿真验证,仿真结果显示接收组件具有较好的噪声系数,发射组件功率输出满足设计指标要求。     

远程I/O系统与DCS通讯的实现

远程I/O系统是一种新型的控制系统 ,近几年来发展迅速 ,应用量越来越大 ,技术上有一定的先进性。文中简要介绍了远程I/O的发展历史和技术特点 ,通过对德国p +f公司RPI和IS -RPI的具体分析 ,旨在使读者对远程I/O接口的技术特点有一个清晰的认识和了解 ,最后对p +f远程I/O接口与典型的DCS系统的通讯方式作了较详细的介绍。