管道多层覆盖层系统的评价

由于单一管道覆盖层的局限性和管道工程建设的需要，覆盖层技术正在向多层结构系统发展。目前多层结构管道覆盖层系统已形成两类，一种是以环氧树脂为主的双层粉末覆盖层，另一种是以聚烯烃树脂为主的复合覆盖层。对新发展的多层结构覆盖层进行了分类和综合评价，指出多层结构系统是今后管道覆盖层的发展趋势。     

Hydrogen as a Probe of Semiconductor Surface Structure: The Ge(111)-c(2 x 8) Surface

Hydrogen can be used as an effective probe of the structure of semiconductor surfaces. Such surfaces consist of bonds with varying degrees of bond strain, and hydrogen can react with each selectively depending on the reaction conditions. This selectivity is derived from a reduced barrier to reaction associated with strained bonds. In this manner, hydrogen can be used to pick apart the surface one bond type at a time, thereby revealing the structure of even complex multilayer reconstructions. This method is used to directly show that the rest-layer of the Ge(111)-c(2 x 8) surface has a bulk structure.     

基于NFC标签的水产养殖质量追溯系统设计

针对水产养殖过程的不合理用药、饲料添加等质量安全问题.应用基于XML/Web服务的数据传递技术构建多层可追溯质量管理系统,并利用NFC标签技术作为在整个水产品流通过程中的身份唯·标识.通过NFC标签,可为生产者、检验者、监督者和消费者提供信息交互平台,真正实现了水产品流通的全程可追溯性.     

Kinetics of single-layer graphite oxidation: evaluation by electron microscopy

Etch-decoration reveals that the rate of removal of carbon atoms exposed at monolayer steps on graphite surfaces is very different from the rate of removal, under identical conditions, at multilayer steps. At 1113 degrees K and a pressure of 1.33 newtons per square meter of oxygen, the rate of oxidation (along the layer planes) is less by a factor of nearly 100 than that at multilayer steps.     

多层社交网络上的谣言传播研究

在线社交网络的普及和发展为信息传播带来了便利，同时也造成了网络谣言的不断滋生和快速传播。针对多层社交网络平台带来的谣言跨平台传播现象，谣言传播的动力学模型被用来模拟多层社交网络中的谣言传播过程。研究发现，谣言在多层社交网络中的传播速度、传播规模都超过单层社交网络，且谣言在多层网络比在单层网络中更容易传播开来；谣言在重构网络中的传播速度和传播规模大于原始的多层网络，并且谣言在重构网络中更容易传播开来。     

一种多层次供应商管理网络的构建及应用——以某乳品加工企业为例

通过分析＂供应商管理＂中存在的问题,指出研究＂供应商管理＂的必要性。结合ABC分析法与XYZ分析法构建了一种实用的多层次供应商管理网络,以某乳品加工企业为例,对该网络的实际应用进行了分析,证明了其可行性和有效性,并对该网络的应用进行了总结与展望。     

Giant birefringent optics in multilayer polymer mirrors

Multilayer mirrors that maintain or increase their reflectivity with increasing incidence angle can be constructed using polymers that exhibit large birefringence in their indices of refraction. The most important feature of these multilayer interference stacks is the index difference in the thickness direction (z axis) relative to the in-plane directions of the film. This z-axis refractive index difference provides a variable that determines the existence and value of the Brewster's angle at layer interfaces, and it controls both the interfacial Fresnel reflection coefficient and the phase relations that determine the optics of multilayer stacks. These films can yield optical results that are difficult or impossible to achieve with conventional multilayer optical designs. The materials and processes necessary to fabricate such films are amenable to large-scale manufacturing.     

Near-infrared Spectral Detection of the Content of Soybean Fat Acids Based on Genetic Multilayer Feed forward Neural Network

In the paper, a method of building mathematic model employing genetic multilayer feed forward neural network is presented, and the quantitative relationship of chemical measured values and near-infrared spectral data is established. In the paper, quantitative mathematic model related chemical assayed values and near-infrared spectral data is established by means of genetic multilayer feed forward neural network, acquired near-infrared spectral data are taken as input of network with the content of five kinds of fat acids tested from chemical method as output,weight values of multilayer feed forward neural network are trained by genetic algorithms and detection model of neural network of soybean is built. A kind of multilayer feed forward neural network trained by genetic algorithms is designed in the paper. Through experiments, all the related coefficients of five fat acids can approach 0.9 which satisfies the preliminary test of soybean breeding.     

Atomic-scale chemical imaging of composition and bonding by aberration-corrected microscopy

Using a fifth-order aberration-corrected scanning transmission electron microscope, which provides a factor of 100 increase in signal over an uncorrected instrument, we demonstrated two-dimensional elemental and valence-sensitive imaging at atomic resolution by means of electron energy-loss spectroscopy, with acquisition times of well under a minute (for a 4096-pixel image). Applying this method to the study of a La(0.7)Sr(0.3)MnO3/SrTiO3 multilayer, we found an asymmetry between the chemical intermixing on the manganese-titanium and lanthanum-strontium sublattices. The measured changes in the titanium bonding as the local environment changed allowed us to distinguish chemical interdiffusion from imaging artifacts.     

不同纳米材料对As(Ⅲ)的吸附机制

为明确不同纳米材料对水中As(Ⅲ)的吸附效果和机制,筛选出经济有效的As污染吸附材料,采用批处理振荡平衡法,研究了多层氧化石墨烯(多层GO)、20 nm羟基磷灰石(P20)、40 nm羟基磷灰石(P40)以及纳米零价铁(n Fe)对As(Ⅲ)的吸附差异性。结果表明,不同纳米材料对As(Ⅲ)的吸附能力存在显著差异(P0.05),吸附容量的大小顺序为多层GO(17.4 mg·g~(-1))P20(2.74 mg·g~(-1))P40(2.17 mg·g~(-1))n Fe(0.976 mg·g~(-1))。其中,多层GO对As(Ⅲ)的吸附效果最好,其饱和吸附量是nFe的17.8倍。通过能量弥散X射线谱(EDS)、X-射线光电子能谱(XPS)、傅里叶红外光谱(FTIR)等对不同纳米材料吸附As(Ⅲ)前后进行分析,证实了多层GO的吸附机制是以单层化学吸附为主;P20、P40、nFe吸附机制为材料表面的聚沉吸附及含氧官能团与As(Ⅲ)发生络合等反应的吸附。实验结果表明多层GO可作为吸附材料用于As(Ⅲ)污染水体的修复。     

现代物业小区车辆智能化综合管理系统

给出了一种现代物业小区车辆智能化综合管理系统，由物业管理中心的中央计算机和下层的各个小区服务器构成多级控制的网络化管理系统，怪实现进出车辆的登记识别、计时计费、等多种功能，并提出了一种能有效识别车辆特征的方法。     

A dielectric omnidirectional reflector

A design criterion that permits truly omnidirectional reflectivity for all polarizations of incident light over a wide selectable range of frequencies was used in fabricating an all-dielectric omnidirectional reflector consisting of multilayer films. The reflector was simply constructed as a stack of nine alternating micrometer-thick layers of polystyrene and tellurium and demonstrates omnidirectional reflection over the wavelength range from 10 to 15 micrometers. Because the omnidirectionality criterion is general, it can be used to design omnidirectional reflectors in many frequency ranges of interest. Potential uses depend on the geometry of the system. For example, coating of an enclosure will result in an optical cavity. A hollow tube will produce a low-loss, broadband waveguide, whereas a planar film could be used as an efficient radiative heat barrier or collector in thermoelectric devices.     

聚多巴胺包覆氟虫腈的制备及缓释性能研究

以盐酸多巴胺（ＤＡ）为单体,以氟虫腈（ＦＩＰ）为模型药物,采用原位聚合法制备聚多巴胺－氟虫腈微胶囊（ＦＩＰ＠ＰＤＡ）,并以其为核,利用多次包覆制备了多层ＰＤＡ包覆ＦＩＰ（ＦＩＰ＠ＰＤＡ－ｎ）．采用ＴＥＭ、ＥＤＸ、ＦＴＩＲ、ＤＳＣ表征了缓释体系的结构与形貌,探讨了体系的黏附和缓释性能．结果表明,ＦＩＰ＠ＰＤＡ－ｎ中的ＦＩＰ以晶体的形式存在;ＦＩＰ＠ＰＤＡ－ｎ具有良好的黏附性;药物释放受包覆层数的影响,当双层包覆时,累积释放率为８５.６％;当６层包覆时,累积释放率为５８.２％．其释药行为可用Ｆｉｒｓｔ－Ｏｒｄｅｒ动力学模型描述,药物释放受控于浓度梯度的扩散．     

磁性多层膜的磁化过程的一种唯象理论研究

计算了磁性多层膜的静磁自由能，采用绝对能量极小模型，导出了磁相变方程，获得了磁相图和磁滞回线．结合局域能量极小模型所得到的磁相图和磁滞回线，讨论了实验上所得到的磁滞回线．     

Jupiter's Clouds: Structure and Composition

Recent infrared radiometric observations of Jupiter have disclosed local temperatures in the North Equatorial Belt far in excess of those at the level of the solid ammonia clouds, and visual observations reveal an orange-brown coloration within this belt. We suggest that, in a multilayer cloud model, solar ultraviolet photolysis of hydrogen sulfide in regions where ammonia clouds are sparse or absent should lead to the production of substantial quantities of inorganic chromophores.     

A hybridization model for the plasmon response of complex nanostructures

We present a simple and intuitive picture, an electromagnetic analog of molecular orbital theory, that describes the plasmon response of complex nanostructures of arbitrary shape. Our model can be understood as the interaction or "hybridization" of elementary plasmons supported by nanostructures of elementary geometries. As an example, the approach is applied to the important case of a four-layer concentric nanoshell, where the hybridization of the plasmons of the inner and outer nanoshells determines the resonant frequencies of the multilayer nanostructure.     

基于双空间特征提取的变压器故障诊断模型

为了提高基于油中溶解气体分析(dissolved gas analysis, DGA)的变压器故障诊断正确率，弥补单子空间特征提取的局限性，提出了基于双子空间特征提取的变压器故障分层诊断模型.首先，将DGA测试样本在一个子空间内进行特征提取后，为避免核函数及其参数的选择难题，以及利用多核支持向量机(multiple-kernel support vector machine, MKSVM)鲁棒性强和精度高的特点，采用MKSVM作为分类器对测试样本进行预测.依据预测结果将测试样本分为难分类和易分类样本，对易分类样本直接进行分类识别；对难分类样本则将该样本再次投影到另一子空间进行特征提取后，同样采用MKSVM作为分类器对难分类样本进行预测，综合两次预测结果进行分类识别，实现两分类MKSVM的双子空间特征提取算法.最后，根据故障特征，建立基于双子空间特征提取算法的变压器故障分层诊断模型.诊断实例表明，该模型具有较高的诊断正确率和推广能力.     

麦秆黄原酸酯的合成条件优化及其在去除沼液中重金属的应用

以麦秸秆为原料制备黄原酸酯类吸附剂,用以处理沼液中的重金属,通过正交实验考察了各种制备因素对铜离子去除率的影响,同时比较了两种用于去除沼液中重金属的工艺流程。结果表明,麦秆黄原酸酯的最佳合成条件为:5g麦秸秆,加入浓度25%的NaOH、0.2mLCS2、25mL1%的硫酸镁,黄化时间3h。沼液中4种重金属的去除率为50.62%~95.27%,去除顺序为Cd>Zn>Pb>Cu。多级过滤明显优于单级过滤,利用所设计的多级过滤滤柱,成功将废水中重金属浓度处理至工业废水排放标准。     

Reducing the dimensionality of data with neural networks

High-dimensional data can be converted to low-dimensional codes by training a multilayer neural network with a small central layer to reconstruct high-dimensional input vectors. Gradient descent can be used for fine-tuning the weights in such "autoencoder" networks, but this works well only if the initial weights are close to a good solution. We describe an effective way of initializing the weights that allows deep autoencoder networks to learn low-dimensional codes that work much better than principal components analysis as a tool to reduce the dimensionality of data.     

Ultrathin films of a polyelectrolyte with layered architecture

Posttransfer modification of preformed Langmuir-Blodgett films of poly(tert-butyl methacrylate) and poly(tert-butyl acrylate) by gaseous hydrochloric acid yields films with layered architecture of poly(methacrylic acid) and poly(acrylic acid), respectively. X-ray reflectivity and infrared spectroscopy confirm monolayer by monolayer transfer of the source polymers and their transformation to acid multilayer assemblies with retention of low surface roughnesses. The incorporation of cross-linking groups into the system offers the possibility for further chemical modification to produce ultrathin films of model networks desirable for bioadsorption studies and as hydrophilic spacing layers for tethered membranes.