基于ASP.NET的Web打印技术研究

打印是很多Web应用系统不可或缺的功能,而且是一项比较复杂的技术,针对ASP.NET中的Web打印问题提出了五种解决方法,并指出每种方法的优缺点,在开发过程中可以根据用户的需求作相应选择。     

建筑空间形式美的探赜

维特鲁威认为建筑是由模式、布置、比例、均衡、适合和经营构成的。在这六个方面中,适合和经营关系到建筑的适用性、经营管理;而前四个方面关系到建筑的模式、结构和外观。他说:"当建筑物的外观优美悦人,细部的比例符合正确的均衡时,就会保持美观的原则。"在维特鲁威的观念中,比例就是建筑美的核心。     

从修辞学的角度对设计符号学中象征功能的再认识

我试图通过解读修辞学的发展历程,探究符号学发展的必然性,由本不存在修辞,到需要修辞,再到修辞的消亡的逻辑关系,联想到设计符号学的发展历程竟与其如此惊人的相似,由仅追求原始功能,到添加装饰满足非本质的需求,继而又摒弃装饰成分,聚焦其本质所在的现代设计,就像我在文章开头说的乙杂邢薜姆绞奖硐治尴蘧褪敲烙是象征的精髓一样,以最简洁的形式传达了最准确的信息,是设计符号学的核心所在。     

单苯环氯取代指数法预测二噁类化合物PCDDs的正辛醇/水分配系数

采用单苯环氯取代指数作为氯代二苯并二口恶口英类化合物 (PCDDs)的分子结构描述符 ,通过正向逐步线性回归方法建立了PCDDs的logKow与分子结构描述符之间的定量关系模型。与文献报道的MOD模型相比 ,该模型不仅具有显著的相关性 (n =43,Radj=0 898,SE =0 195 ,在α =0 0 5时 ,F =2 0 45 5 ,p =0 0 0 0 0 ) ,而且对于分子结构具有更好的区分能力。利用建立的模型 ,对没有logKow文献值的其他 33种PCDDs化合物给出了预测值     

现代化水利建设迫切需要完善质量监督工作体系

江苏省的市、县级水利工程质量监督体系尚未建立,远未健全。质量监督存在制度不完善、效能不到位等问题。今后一个时期,大规模水利建设和水利现代化建设,需要质量监督作为工程质量重要保障,应通过健全监督体系、完善监督制度、抓住质量监督重心、强化质量检测管理、实现全程监督检查等措施,来确保质量监督工作的成效。     

浅析AP1000核电技术对中国内陆核电发展的适应性

介绍了世界内陆核电发展概况,分析了中国内陆核电发展的必要性,从水资源安全、核辐射安全和公众环境安全角度分别论述了AP1000核电技术对内陆核电的适应性。     

两种水轮发电机组开机控制技术的比较及优化

本文建立了水轮发电机组仿真模型,并以某电站的水流特性、机组惯性等实际参数作为仿真模型参数,着重研究水轮发电机组的两种开机控制规律,分析了原有以空载开度为限制的机组开机控制技术,提出以恒转速变化率为控制目标的机组开机控制技术,并将两种开机控制技术进行了仿真比较。通过仿真波形分析比较表明,两种开机控制技术各自具有的优越动态性能。在工程实践中,将这两种开机控制技术都应用到水轮机调速器开机程序中,可以根据水电站现场对开机动态性能的不同要求在停机态切换两种开机控制流程。     

A new sorbent that simultaneously sequesters multiple classes ofpollutants from water: Surfactant modified zeolite

A zeolite (ZFA) was synthesized from coal fly ash and then modified using hexadecyltrimethylammonium. The surfactant modified ZFA (SMZFA) was evaluated for its versatility to sequester multiple classes of pollutants from water. The target pollutants include ionic inorganic pollutants (ammonium and phosphate), ionic organic pollutants (methylene blue and humic acid), ionizable organic pollutants (bisphenol A,-chlorophenol and phenol, with different pKa), and electrically neutral or-ganic pollutants (aniline, nitrobenzene, and naphthalene, with different hydrophobicity). The SMZFA showed high potential for the retention of ammonium and phosphate, being comparable with ZFA. While the negative charge in the internal pores of zeolite was responsible for the retention of ammonium, the oxides of CaO, Al2O3and Fe2O3in the non-zeolite fraction, which originated from coal fly ash but received modification during zeolite synthesis, accounted for the removal of phosphate. Results also showed that while ZFA had little affinity for humic acid, the ionizable, and the electrically neutral organic compounds, SMZFA exhibited greatly enhanced adsorption capacity. Thus, the surfactant modified external surface, which formed a bilayer micelle of zeolite, imparts a hydrophobic characteristic that enables the uptake of the organic pollutants. We showed that SMZFA is a promising versatile sorbent for water treatment.     

Study of partial discharge characteristics at repetitive square voltages based on UHF method

Due to overvoltage produced by inverter output,inverter-fed motor insulation systems often experience fast electrical aging process,especially when partial discharge(PD) is incepted.Before putting into use,the PD detection should be performed on inverter-fed motors at repetitive square voltages to avoid the PD caused insulation deterioration when the motors are collected to inverters having specific characteristics.However,unlike PD tests at AC/DC voltages proposed in IEC 60270,the PD detection at repetitive square voltages is much more complex because of serious interference generated by impulse generator.To solve the problem,ultra-high frequency(UHF) method seems recommendable for its preferable signal-to-noise ratio(SNR).The chief aim of this study is to investigate PD pulse and statistical characteristics of turn-to-turn insulation for inverter-fed traction motors.A square-shaped Archimedes antenna,specially designed for the PD detection at repetitive square voltages of fast rise times,was used to perform PD tests on turn-to-turn insulation models.Time and frequency analysis results indicate that energy component of generator disturbance and PD pulses are mainly distributed in the 0-0.5 GHz and 0.6-1.5 GHz range,respectively.Based on the results,suitable filter was designed for power disturbance suppression.Additionally,resorting to the sensor unit(i.e.antenna and filter) and the PD test system,the PD statistical features at square voltages of different frequencies were obtained.Experimental results show that higher frequency will give rise,statistically,to PD of lower magnitudes distributing at smaller phases.A reasonable interpretation of this phenomenon was presented.Lastly,according to the PD statistical features,some suggestions for the PD detection system design,generator parameter optimization and the PD pulse extracting were given.The results of this work would be beneficial to the increase of the sensitivity when performing the PD detection on insulation systems for inverter-fed motors at repetitive square voltages and thus,improving the reliability of inverter-fed motors.     

龙开口水电站枢纽工程关键技术研究

龙开口水电站枢纽采取主河床泄洪、右岸坝后厂房布置形式,大坝为碾压混凝土重力坝.大坝的防震抗震,右岸变形体边坡治理,骨料料源选择、加工及运输,河中深槽处理,施工导流技术,泄洪消能技术,尾水渠粉质边坡治理等问题是工程建设的关键技术问题.针对这些问题,在可研、招标及技施阶段开展了大量研究工作,取得了许多有价值的成果,最终制定了合理的设计方案,为工程建设提供了技术保障.