电子数据备份方法探讨

在广泛开展的信息化工作中,由于各种原因引起的电子数据丢失时常发生,当丢失的数据无法恢复时会造成不同程度的损失,因此需要对电子数据进行安全备份。针对电子数据备份的重要性及经常发生的问题,论述了数据备份的方式和等级,提出了加强数据备份的管理,健全管理制度以及完善数据备份的过程与环节。应用相关技术,在确保安全的前提下,选择操作性强、成本较低的备份方式和等级,充分发挥数据备份的作用。     

Airborne differences in odors emitted byRattus norvegicus in response to reward and nonreward

To test the hypothesis that rats (Rattus norvegicus) emit airborne, differential odors in response to reward and nonreward, donor rats received random sequences of rewarded and nonrewarded placements in small compartments and an airstream transported odors from these compartments to test rats in a separate chamber. When donors remained in the compartments during, or were removed just prior to, air transport, test rats utilized transported odors as discriminative cues signaling their own reward and nonreward for a lever-press response. When the airstream was passed through a clean compartment containing paper flooring extracted from donor compartments, test rats were not able to discriminate. Test trials to assess for control by food odors suggest that donor-produced odors, rather than food odors per se, provided the discriminative signals for test rats. Results confirm the existence of somewhat volatile, although apparently stable, odors emitted in response to reward and nonreward, and implicate a differential in amount and/or type of odor produced by donors to these two events as the source of discriminative control.     

The Pigmentation of Acrylic Resins*

Acrylic resins may be divided into two main categories—solvent-bome and water-borne systems—and these have been further subdivided into two groups, namely solutions and dispersions. Problems associated with the pigmentation of acrylic resins are discussed, and methods of assessing the wetting properties of the system are mentioned. The use of wetting and dispersing agents is examined, and the concept of the hydrophilic-lyophilic balance (HLB) value is investigated in this context. Pigmentation is one important factor that must be considered in assessing the exterior durability of acrylic resins, certain types of which are ideal media for metallic finishes because of their excellent polishing and weathering properties. The phenomenon of geometric metamerism associated with metallic finishes is discussed.     

MODIS数据Bowtie效应消除算法

MODIS数据不仅具有较高的过境频率和光谱分辨率,还具有成本低、覆盖面广等优势。受地球曲率的影响,MODIS L1B数据大多存在一种重叠效应,即Bowtie效应,主要发生在图像的边缘地带,该效应制约了MODIS遥感数据的进一步分析及应用。针对遥感影像几何畸变问题,提出一种不基于传统星历表的Bowtie效应消除算法,采用相关系数法确定每个扫描带的重复行数,根据不同分辨率的MODIS L1B数据,使用相对应的重采样方法对图像进行重采样处理。通过与其他Bowtie效应消除算法的对比实验及分析,证明该算法不仅能够有效去除Bowtie效应,而且执行速度较快,具有较高的工程应用价值。     

荧光法测定N-（α-烷苯氧基）十四酰基牛磺酸钠的临界胶束浓度

研究了一类以苯氧基作疏水支链的新型阴离子表面活性剂——N-（α-烷苯氧基）十四酰基牛磺酸钠（SAPTT）水溶液的紫外吸收光谱、探针（芘）稳态荧光发射光谱及自身稳态荧光发射光谱性质．研究结果表明，荧光探针（芘）法和自身稳态荧光法可用来测定这类表面活性剂的临界胶束浓度（CMC），且测定结果与表面张力法（吊片法）接近；与荧光探针（芘）法相比，对于所研究体系，自身稳态荧光法的灵敏度和准确性均较高，所测得CMC结果与表面张力法（吊片法）能较好地吻合．     

Oxidation of Butane to Maleic Anhydride using Vanadium Phosphate Catalysts: Comparison of Operation in Aerobic and Anaerobic Conditions using a Gas-gas Periodic Flow Reactor

The use of a periodic flow reactor is described for the oxidation of butane to maleic anhydride to compare the catalytic performance of vanadium phosphate catalysts operating under aerobic and anaerobic conditions. It is found that for the catalyst prepared via a standard VPO method, operation in the absence of oxygen leads to a very small enhancement in selectivity when butane concentrations in the range 0.9–2.9% are used. Operation in the absence of oxygen leads to very small differences in conversion such that the overall yield is enhanced and this effect is maximised for reactor feeds containing 1.5% butane. However, the enhancement is negligible when the catalyst is operated at high conversion required for commercial operation, indicating that reactors operating with continuous flow with aerobic conditions are preferred. Similar experiments are conducted for a catalyst prepared by the VPD method and, in contrast, this catalyst gives lower butane conversion and maleic anhydride selectivity when operated in the absence of oxygen.     

智能公交移动平台实时查询客户端

随着智能手机和高速移动网络的普及,智能公交查询系统作为一个城市化的公共信息平台,可较大程度上方便广大民众的日常出行．目前,Android平台上的公交查询客户端分为两种,一种是查询静态信息,如换乘方案,线路信息等,另外一种是公交实时运行状况的查询．本文在传统设计的基础上,采用本地数据库和HTTP连接双重查询方式,通过解析JSON数据,设计并实现了具有自动刷新功能的移动平台公交实时查询软件．在查询站点信息和线路信息基础上,将线路上即将到站车辆的运行位置信息实时显示在页面上,从而使用户清晰的了解当前公交运行情况,适当调节自己的出行计划,具有较高的现实意义．     

具有椭圆盘极点约束的线性系统滤波器设计

针对一类线性系统,研究其闭环系统极点具有椭圆盘约束的情况下滤波器设计问题。在极点约束的前提下,控制目标要求闭环系统渐近稳定,并且干扰抑制性能指标小于给定的上界。首先利用有界实引理给出椭圆盘极点约束前提下滤波器的存在条件;其次,利用线性矩阵不等式技术,将滤波器的存在性问题转化成一组线性矩阵不等式(LMI)的可行性问题,根据LMI的可行解,给出滤波器的设计方法,由该方法得到的滤波器满足给定的性能要求;最后,数值算例说明该方法的有效性和可行性。     

NHD脱碳工段技改总结

合成氨装置脱碳工段采用NHD脱碳工艺,由于脱碳后的脱碳气中CO2含量偏高,造成H 2损耗较大,为此采用ZUPAC系列双向金属折峰式波纹填料和新型槽盘式液体分布器对脱碳塔进行改造。改造后,脱碳气中CO2体积分数从2.0%降至1.6%,年可增加经济效益1000万元左右。     

均匀沉淀法制备纳米氧化锌和片状氧化锌粉体

以氯化锌、尿素为原料 ,采用均匀沉淀法在一定条件下制备得到纳米级氧化锌粉体。并以TEM、SEM、XRD等测试手段对产物的粉体结构、形貌进行了研究。结果表明 ,在 2 0 0℃下热处理得到的氧化锌粉体结晶性能良好 ;在较大的反应物浓度及反应物浓度比下可以得到较小的晶体粒径 ,平均为 2 0nm ,且分散性好 ;在较小的浓度及较小的浓度比下得到的晶体粒径较大 ,并呈片状生长。阐述了浓度对于粒径大小的影响并得出片状氧化锌微晶生长的最佳条件。