一种安全协议的安全性分析及攻击研究

针对Web安全协议SSL的握手协议部分进行了详尽的阐述，对其安全性作了一定的分析，给出了理论上存在的三个协议漏洞的详尽描述，并且经过测试验证，指出了SSL协议存在***模式漏洞。     

可溶性盐复分解法碳酸钙制备影响因素研究

采用可溶性盐复分解法进行碳酸钙合成影响因素及其机理的研究。以正交试验法对合成温度、pH值、反应物浓度在碳酸钙合成中的影响进行探索,验证了温度以及pH值在合成反应中对产物晶型、形貌以及尺度有显著影响;使用周期键链理论(PBC)讨论了碳酸钙晶体方解石/文石共生现象;研究观察Mg2+对碳酸钙合成的影响,Mg2+作为能够稳定无定形碳酸钙前驱体(ACC)的金属离子,大量存在时碳酸钙形貌随nMg/nCa增大而变化,同时颗粒尺度变小。     

Selective deposition on block copolymer film by thermal evaporation of silver

Selective deposition of Ag onto nanostructured block copolymer film template of poly(ethylene oxide) and poly(methacrylate) with azobenzene mesogen (PEO-b-PMA(Az)) has been done by thermal evaporation technique. A hexagonally arranged pattern or ordered strip structure of the PEO nanocylinders dispersed in the PMA(Az) matrix appears on the pure copolymer film surface after thermal annealing at 140 °C or 110 °C, respectively. Atomic force microscopy confirms that the deposited Ag atoms prefer to wet PMA(Az) matrix domains on the film surface, and finally aggregate into discrete nanoparticles in both cases. An ordered porous metallic layer is created on the hexagonally patterned copolymer template surface due to the preferential interaction of Ag toward the PMA(Az) phase. Alternatively, ordered array of metallic chains is formed on the template featured with strip structure. While the nominal layer thickness of the deposited Ag is 50 nm, the ordered metallic nanostructure disappears, indicating the host copolymer template cannot guide the spatial distribution of the deposited metal any more.     

机械臂与环境交互的位置/力切换抑制振动方法

当机械臂执行位置/力的混合跟踪任务时，位置控制一般用于机械臂的自由运动阶段，力控制一般用于约束运动阶段。这种位置/力切换的控制结构既能实现与环境接触前对机械臂位置的精确控制，也能保证接触后对期望控制力的准确跟踪。由于开关系统本身存在的切换不稳定性，机械臂在以一定的速度与环境接触时，机械臂执行器会在环境表面振动甚至弹跳。针对此问题，提出了一种半主动阻尼阻抗学习方法，该方法主要包含两部分：基于位置/力切换控制的半主动阻尼控制器；基于一种逆秩拟牛顿法（broyden fletcher goldfarb shanno，简称BFGS）的阻抗学习算法，根据学习到的环境参数调节半主动阻尼，实现机械臂在接触面的振动抑制和平稳过渡。在仿真及实验中，应用提出的方法让机械臂与不同环境交互，结果表明：该方法能很好地抑制接触过渡阶段的超调力，并防止机械臂在切换过程中的振动，实现了柔顺接触和平稳过渡。     

鳡鱼副产品制备鱼冻的研究

为提高鳡鱼加工副产品的利用率,本研究以鳡鱼骨、鱼皮、鱼鳞等为原料,采用提取、调味、成型等工艺制备鱼冻产品。经单因素实验获得鳡鱼冻质构(包括弹性和硬度)的可优化参数。正交实验结果表明,提取时酸化剂(柠檬酸∶醋酸=1∶1)3%(v/m)、氯化钠3%(m/m),调配时卡拉胶1.1%(m/m)鳡鱼冻产品的硬度为2403N,风味良好,氨基酸含量与鳡鱼肌肉组成类似、基本满足FAO/WHO的建议模式。     

装卸用直臂架多用途门机典型起升钢丝绳卷绕系统的分析与比较

通过详细地分析和比较已被上海振华重工(ZPMC)完成项目中3种典型的装卸用直臂架多用途门机的起升钢丝绳卷绕形式,总结出每种卷绕形式的特点和各自的适用条件,对今后提高装卸用直臂架门机的设计和制造的综合质量具有一定的指导意义。     

美国分区规划制度分析

介绍了美国分区规划的产生、发展历程及管理体系,分析了在美国的社会、经济及政治背景下,分区规划所出现的一系列经济、社会问题,并总结了美国分区规划对我国城市规划的影响。     

In-Situ Analyzing the Influence of Thermoelectromagnetic Convection on the Nucleation Ahead of the Advancing Interface During Directional Solidification

Sn-3wt%Pb alloy was directionally solidified without and with a 0.08T transverse magnetic field(TMF),and real-time recorded by in-situ synchrotron X-ray imaging.Results indicate that TMF shortened the distance from the location of nucleation to the advancing interface,and accelerated the growth rate of the equiaxed crystal,which caused the columnar-to-equiaxed transition(CET)finally.The thermoelectromagnetic convection(TEMC)in front of the interface and around the crystal’s dendritic branch should respond to changes of the distance and the growth rate.     

城市树木致伤风险可视化评估：以武汉市 中山公园为例

城市中的树木能提供多种生态系统服务，但树木倒 伏、树枝坠落也可能致人伤害，评估城市树木风险能有效地预 防伤害发生、保障人身安全。但当前研究的评估维度多聚焦于 树木自身，对城市人群致伤可能性的考量较少。建构了风险严 重性、风险可能性和致伤潜力3个维度的城市树木致伤风险指 数(I UTIR)评估方法，以武汉市中山公园为例展开树木致伤风险 评估，并分析了树木自身风险、致伤潜力与致伤风险之间的空 间关系。研究发现：68.7%的区域中，树木自身风险与致伤潜 力之间的空间关系呈现正相关性，25.1%的区域呈现负相关 性。在此基础上，提出了预防树木致伤风险的管理建议。为公 园规划设计和树木风险管理策略提供参考，从而减弱树木致伤 风险对人体健康的影响。     

Electrochemical performance of LiVPO4F/C synthesized by different methods

LiVPO₄F/C samples were synthesized by one-step solid-state reaction and two-step solid-state reaction methods, respectively. The X-ray diffraction (XRD), scanning electron microscopy (SEM) and electrochemical performance tests were adopted to characterize the properties of LiVPO₄F/C. XRD results show that the LiVPO₄F/C samples prepared by one-step solid-state reaction method have the same triclinic structure (space group as that synthesized by conventional two-step solid-state reaction. SEM image exhibits that the particle size of LiVPO₄F/C prepared by one-step solid-state reaction method is smaller than that of the sample synthesized by two-step solid-state reaction. The improved electrochemical properties of the LiVPO₄F/C are attributed to the depressed grain size and enhanced electrical conductivity produced via one-step solid-state reaction method using oxalic acid as both reduction agent and carbon sources. AC impedance measurements also show that the LiVPO₄F/C synthesized by one-step solid-state reaction route significantly decreases the charge-transfer resistance.