高锰酸盐复合药剂预氧化去除腐植酸色度研究

选取三种不同类型的辅剂与高锰酸钾复合,研制出高锰酸盐复合药剂PPC—A、PPC-N和PPC-C,并对三种高锰酸盐复合药剂对腐植酸色度的去除效能进行研究。研究结果表明,与单独投加硫酸铝相比,投加少量高锰酸盐复合药剂就可以显著提高对色度、TOC及UV254的去除效果,并且对加氯消毒后氯仿生成量也有较好的控制作用。三种复合药剂中,PPC-C具有最优的除色效能。高锰酸盐复合药剂对腐植酸的去除是高锰酸钾、新生态水合二氧化锰及辅剂共同作用的结果。     

微细蒙脱石颗粒界面疏水改性机理研究

采用密度泛函理论方法计算了不同甲基取代程度的甲基胺类(伯胺、仲胺、叔胺和季铵)的分子形式和离子形式在蒙脱石(001)表面上的吸附能、吸附平衡构型和差分电子密度,并测试了药剂作用后蒙脱石悬浮液上清液透光率、表面对药剂的吸附量和表面接触角。结果表明:甲基胺类离子形式在蒙脱石表面的吸附能比分子形式的大很多,可以稳定吸附在表面上;烷基胺中N原子上的甲基对H原子的取代程度越高,吸附能越小,对蒙脱石表面的疏水改性能力越差;甲基胺类阳离子主要通过静电作用和氢键作用吸附到蒙脱石表面上;药剂作用后蒙脱石悬浮液的上清液透光率、表面对药剂吸附量和表面接触角的试验结果与模拟结果相一致。     

艾司唑仑治疗神经官能症性心脏病的现代化研究

目的：探究艾司唑仑对神经官能性心脏病的疗效,作出分析。方法：对58为患有神经官能性心脏病的病人进行分组治疗和观察,两组分别选取不同的抗焦虑药剂,进行临床观察。结果：艾司唑仑作为抗焦虑药剂的实践组疗效远远好于使用其他药剂的实验组。结论：艾司唑仑作为抗焦虑药剂的效果相对好,因此可以广泛应用于神经官能性心脏病的治疗中。     

煤矿许用电雷管药剂爆温的理论计算与分析

运用B—W法确定煤矿许用电雷管药剂的爆炸反应方程式,用盖斯定律计算定容爆热,用加权法计算爆炸产物的摩尔定容热容,研究计算得出采用冰晶石作消焰剂的煤矿许用电雷管药剂常见配方的爆热、爆温数据,并对计算结果进行了分析与讨论。计算结果显示随着冰晶石含量的增加,煤矿许用电雷管药剂的爆热、爆温分别呈现下降趋势。     

烟火剂安定性的影响因素分析

文章就烟花爆竹药剂的吸湿性、药剂间的相容性、药剂比表面积、药剂化学性质以及加入其它助剂等对烟火剂安定性的影响进行了分析。为烟花爆竹的安全制造、储存和使用提供了一定的参考价值。     

黄河源水投加聚合氯化铝铁生产试验

本文针对我司多年来在黄河原水3000HTU以下投加二甲基二烯丙基氯化铵高分子阳离子混凝剂,造成投加药剂费用高、生产成本大的现状。从生产实际出发,根据我司水质中心实验室实验结果,将实验数据换算为具体的生产数据,通过生产性实验,分析比较聚合氯化铝铁与二甲基二烯丙基氯化铵两种药剂投加后的水质效果和经济比较,确定科学合理的药剂投加对照表,指导实际生产。     

基于野生马蹄金种子萌发的研究

本试验以不同药剂(次氯酸钠、硝酸钾、赤霉素)处理4份西南野生马蹄金种子,研究不同药剂对野生马蹄金发芽率和发芽势的影响,筛选适宜野生马蹄金种子萌发的最佳药剂及其浓度,为进一步开发利用野生马蹄金资源提供理论基础。     

化学药剂在矿物加工中的应用分析

随着经济社会的发展,人们对于矿区资源的需求不断增加,矿物生产加工期间,化学药剂的使用是一个重要环节,直接影响加工效率和产品质量。要想正确使用不同的药剂,应该了解各自的化学特性、反应机理,从而充分发挥出功能作用。本文从无机药剂、溶剂萃取药剂、合成聚合药剂、浮选药剂4个方面,介绍了在矿物加工中的应用,以供参考。     

烟花爆竹用有色火焰药剂燃放有害气体产物研究

文章通过最小自由能法理论计算和模拟实验研究,选取典型烟花爆竹产品中较为常用的红、绿、蓝、黄焰色药剂为研究对象,对烟花爆竹用有色火焰药剂燃放时的有害气体产物开展了研究。结果表明:有色火焰药剂燃放产物中的有害气体产物主要为CO,有色火焰药剂配方的负氧平衡是其燃放产物中有CO生成的主要原因,提高配方氧平衡可减少CO的生成。     

退役火药制备环保型烟花药剂的基本技术分析

文章分析比较了传统烟花药剂和退役火药的燃烧基本性能,阐述了传统烟花和现代烟花对药剂的技术要求,指出了利用退役火药制备安全环保型烟花药剂所应解决的关键技术.     

Thermophysical properties of some key solids: An update

In 1985, the CODATA Bulletin published a Report of its Task Group on Thermophysical Properties of Solids which analyzed available data on, and gave recommended values for, the heat capacity of Cu, Fe, W, and Al₂O₃, the thermal expansion of Cu, Si, W, and Al₂O₃, the electrical resistivity of Cu, Fe, Pt, and W, the thermal conductivity of Al, Cu, Fe, and W, and the absolute thermopower of Pb, Cu, Pt, and W. The analysts for the different properties were R. B. Castanet, S. J. Collocott, P. D. Desai, C. Y. Ho, J. G. Hust, R. B. Roberts, C. A. Swenson, and G. K. White. The present paper is an updated version of the earlier report and includes more recent data which change some of the recommended values. notably the heat capacity of Cu and W and the thermal expansion of Si and W.     

Age and pedestrian injury severity in motor-vehicle crashes: a heteroskedastic logit analysis

This research explores the injury severity of pedestrians in motor-vehicle crashes. It is hypothesized that the variance of unobserved pedestrian characteristics increases with age. In response, a heteroskedastic generalized extreme value model is used. The analysis links explanatory factors with four injury outcomes: fatal, incapacitating, non-incapacitating, and possible or no injury. Police-reported crash data between 1997 and 2000 from North Carolina, USA, are used. The results show that pedestrian age induces heteroskedasticity which affects the probability of fatal injury. The effect grows more pronounced with increasing age past 65. The heteroskedastic model provides a better fit than the multinomial logit model. Notable factors increasing the probability of fatal pedestrian injury: increasing pedestrian age, male driver, intoxicated driver (2.7 times greater probability of fatality), traffic sign, commercial area, darkness with or without streetlights (2-4 times greater probability of fatality), sport-utility vehicle, truck, freeway, two-way divided roadway, speeding-involved, off roadway, motorist turning or backing, both driver and pedestrian at fault, and pedestrian only at fault. Conversely, the probability of a fatal injury decreased: with increasing driver age, during the PM traffic peak, with traffic signal control, in inclement weather, on a curved roadway, at a crosswalk, and when walking along roadway.     

纳米技术：新世纪的机遇和挑战

纳米技术是二十一世纪最具发展前景的领域,当前,在全球范围内,一个以纳米材料,纳米电子学和纳米医疗为核心的高科技时代已经来临,很多产业都将因纳米技术的发展而得益,如通讯、计算机、医疗、化工、材料、能源、飞机、汽车、航天、环保和机械制造等。而且十分明显的是,几乎所有的方面都涉及或依赖于真空科学与技术。     

An Approach to Calculate Thermodynamic Properties of Mixtures Including Propane, <Emphasis Type="Italic">n</Emphasis>-Butane,and Isobutane

This paper discusses a mathematical model for computing the thermodynamic properties of propane, n-butane, isobutane, and their mixtures, in the fluid phase using a method based upon statistical chain theory. The constants necessary for computations such as the characteristic temperatures of rotation, electronic state, etc. and the moments of inertia are obtained analytically applying a knowledge of the atomic structure of the molecule. The paper presents a procedure for calculating thermodynamic properties such as pressure, speed of sound, the Joule-Thomson coefficient, compressibility, enthalpy, and thermal expansion coefficient. This paper will discuss, for the first time, the application of statistical chain theory for accurate properties of binary and ternary mixtures including propane, n-butane, and isobutane, in their entire fluid phases. To calculate the thermodynamic properties of Lennard-Jones chains, the Liu-Li-Lu model has been used. The thermodynamic properties of the hydrocarbon mixtures are obtained using the one-fluid theory. Paper presented at the Fifteenth Symposium on Theremophysical Properties, June 22–27, 2003, Boulder, Colorado, U.S.A.     

Hybrid features-enabled dragon deep belief neural network for activity recognition

Activity recognition is a challenging task in computer vision that finds widespread applications in various fields, such as motion capture, video retrieval, security, and video surveillance. The objective of this work is to present a technique for recognizing human activities in videos using Dragon Deep Belief Network (DDBN) and hybrid features, which comprises of features like shape, coverage factor, and Space-Time Interest (STI) points. Initially, the keyframes from the input video sequence are extracted using Structural Similarity (SSIM) measure. Then, the features, such as shape, coverage factor, and STI points, are extracted from the keyframes. Based on the feature vector extracted, the proposed DDBN classifier, which is designed by the effective combination of DBN and Dragonfly Algorithm (DA), a classification on human activities, such as walk, bend, etc. in videos. In DDBN, the weights in the network are selected optimally using DA. The weight update using the DA for each incoming feature improves the performance of the DDBN classifier. Further it improves the accuracy in classification of actions. The proposed DDBN classifier is experimented using KTH and Weizmann datasets based on three evaluation parameters, such as accuracy, sensitivity, and specificity. From the performance evaluation, the proposed DDBN classifier could attain better performance with the probability of 98.5% accuracy, 0.96 sensitivity, and 0.959 specificity, respectively.     

材料医学和医学材料

临床医学和生物材料的蓬勃发展, 促进了多种疾病的诊断成像、有效治疗和精准诊疗。材料与医学交叉学科(简称“材料医学”)的发展旨在克服传统临床医学面临的主要障碍和挑战, 如系统性毒性、生物利用度差、靶向部位特异性低、诊断/治疗效果不理想等。本文系统地阐述了近年来各种医学材料在疾病诊断、治疗和诊疗方面的应用进展, 特别是纳米医学材料的研究进展。首先, 重点讨论癌症治疗领域的生物医学成像(如光学成像、磁共振成像、超声成像、计算机断层成像等)和治疗策略(如光热治疗、动力学治疗、免疫治疗、协同治疗等)。此外, 我们还重点介绍了医学材料对骨组织工程、呼吸系统、中枢神经系统等疾病的诊断和治疗的最新进展, 并重点阐述了用于生物传感和抗微生物等其他代表性生物医学领域的医学材料。最后, 我们讨论了这些独特的医学材料在实际临床转化和应用中所面临的挑战和未来的机遇, 以促进其早日实现临床转化, 推动医学进步和造福患者。     

Pressure drop in riser and evaporator in an advanced two-phase thermosyphon loop

This study presents an experimental investigation of pressure drop in the evaporators and the riser of an advanced thermosyphon loop. The thermosyphon was designed for the cooling of three parallel high heat flux electronic components. The tested evaporators were made from small blocks of copper in which 7, 5, 4, 3, 2, 1 vertical channels with the diameters of 1.1, 1.5, 1.9, 2.5, 3.5 and 6 mm, respectively, and a length of 14.6 mm were drilled. Tests were done with isobutane at heat fluxes ranging between 22.4 and 303 kW/m². For prediction of the pressure drop, in the riser, different combinations of frictional pressure drop and void fraction correlations were tested. Regarding the evaporator a simple correlation based on a homogeneous model [M.B. Bowers, I. Mudawar, Two-phase electronic cooling using mini-channel and macro-channel heat-sinks—part II, flow rate and pressure drop constraints, ASME J Electron Packaging 116 (1994) 298–305. [1]] has been used to predict the pressure drop.     

Studies on Mechanical, Friction, and Wear Characteristics of Kevlar and Glass Fiber-Reinforced Friction Materials

Asbestos possesses properties that are ideally suitable for use as a friction material in automotive and a number of other applications. Animal and human studies carried out since the early 1900s have established that asbestos is carcinogenic and that exposure to especially asbestos dust causes a large number of diseases. Realizing the health hazards posed by asbestos, many countries started phasing out asbestos from all asbestos-containing products since the 1980s. Some of them imposed a total ban in the 1990s on the use of asbestos-containing friction products. This situation forced many manufacturers to look for alternatives to asbestos. But the efforts have only been partly successful. The search is, therefore, still on to find suitable substitutes for asbestos. Though steel wool, Kevlar, glass, and a number of other mineral fibers have been tried out on an experimental basis over the last two decades, glass and Kevlar fibers, in particular, have shown promise as potential substitutes for asbestos. These days, therefore, studies on polymer-based friction materials reinforced with glass, Kevlar, and ceramic fibers are being pursued with much fervor. However, conflicting views are prevailing even today as to the suitability of asbestos-free composites for automotive applications and freedom from the concomitant health risks posed by them. In the present work, therefore, phenolic resin matrix samples reinforced with different amounts of glass and Kevlar fibers were produced and characterized for their mechanical, physical, friction, and wear properties to assess their suitability for light passenger car applications. The study establishes that composites based on glass and Kevlar fibers show good mechanical, physical, friction, and wear characteristics, enhancing thereby their suitability for automotive applications. The property improvements achieved are correlated to the composition, microstructure, and the changes taking place on the surface of the friction composites.     

多波束测深系统多子阵检测法的改进及其性能分析

多波束测深系统中,相位检测法是实现超宽覆盖测量的关键技术之一。分析了分裂子阵相位检测法和多子阵检测法,并基于对子阵结构的分析,改进了多子阵检测法,给出了多子阵检测法输出信噪比的表达式,讨论了子阵结构对输出信噪比的影响,在理论分析基础上选择了三种子阵结构对海上试验数据进行了处理,验证了分析结果。处理结果表明,在优化参数基础上,多子阵检测法不但可实现多波束测深系统的超宽覆盖,而且可改善系统对海底的检测性能。     

铈、镧掺杂BaTiO3 基纳米晶的合成与表征

以非全醇盐为原料并避开传统的醇类有机溶剂,利用溶胶－凝胶法以醋酸为介质兼作均相催化剂,按不同配比及工艺条件合成了分别掺杂铈或镧的ＢａＴｉＯ３基纳米晶。利用ＤＴＡ－ＴＧ、ＸＲＤ、ＦＴ－ＩＲ、ＸＲＦ、ＳＥＭ以及陶瓷元件气湿敏特性等测试对纳米晶进行了表征,确定了制备浓溶胶前驱体的优化工艺、酸度、温度、浓度配比、次序、干燥方式等;测定了多晶粉体的原始晶粒粒度、纯度、晶相、软团聚颗粒外观形貌、粒度分布等。