不同引发剂引发苯乙烯/丙烯酸丁酯微乳液共聚合竞聚率的研究

以十二烷基硫酸钠/十二烷基苯磺酸钠(SDS/SDBS)为复合乳化剂,分别以水溶性引发剂过硫酸钾(KPS)、油溶性引发剂过氧化苯甲酰(BPO)和氧化-还原引发体系K₂S₂O₈/Na₂SO₃(OR)引发苯乙烯/丙烯酸丁酯(St/BA)微乳液聚合反应,研究了St/BA微乳液共聚合行为,用红外光谱法定量测定了3种引发剂下的共聚物化学组成,绘制了共聚物组成曲线,计算出了竞聚率。     

正交异性板的孔边应力

文中导出带孔正交异性无限大板受任意比例、任意方向的双向作用力时,孔边应力计算公式。还用有限元法计算了工程中常用的几种正交各向异性有限宽板受各种载荷时孔边的应力集中,给出了应力集中系数随孔中心到板边的距离与孔半径之比 D/ρ的变化曲线。指出当 D/ρ大于4时,按无限大板处理,误差将不大于5%。     

石家庄市冬防期细颗粒物污染特征及源解析

为了探究石家庄市冬防期细颗粒物（PM_2.5）的主要污染来源,推动石家庄市环境空气质量持续改善,采用在线单颗粒气溶胶质谱仪（SPAMS）捕集的PM_2.5粒子信息,结合自适应共振神经网络分类方法（ART-2a）和石家庄市污染源谱图信息,对2017年10月1日—2018年3月31日、2019年10月1日—2020年3月31日、2021年10月1日—2022年3月31日的石家庄市PM_2.5污染物来源进行解析。结果表明：1）石家庄市冬防期PM_2.5主要受燃煤源、机动车尾气源、工业工艺源共同作用的影响,3种污染源对PM_2.5浓度的贡献率超过60%;2）第3阶段与前2个阶段相比,在不同月份和污染时段机动车尾气源对PM_2.5贡献率占比均升高9个百分点以上,贡献占比最大,机动车尾气源逐渐取代工业工艺源成为PM_2.5首要污染源;3）受春节影响,2月份机动车尾气源对PM_2.5贡献率明显降低;4）第3阶段燃煤源和工业工艺源对PM_2.5浓度的影响降低,但2个污染源对PM_2.5浓度的贡献率仍然较大,贡献占比超过30%。研究结果为石家庄市进一步加强对机动车尾气源的管控提供了依据,同时对未来石家庄市提前采取针对性污染源管控,减缓大气污染的发生提供了数据支撑。     

表面流人工湿地污染物去除与运行参数的相关性及其反应动力学

为了探讨利用人工湿地处理农村污水的效益状况,以表面流人工湿地为研究对象,探析人工湿地去除污染物的运行规律。自2017年8月至2019年5月,每周采集水样一次,共累计取样88组;分别测定SS,BOD₅,TN,TP等污染物指标以及流量（Q）、水温（T）,DO,pH值等运行指标;并分析了SS,BOD₅,TN,TP等4种污染物的出水浓度、去除率、表面污染物负荷（PLR）分别与表面水力负荷（HLR）、水力停留时间（HRT）的相关性,以及4种污染物的一级反应速率常数（k_V）与Q,HLR,HRT的相关性,最后根据线性相关性方程计算出4种污染物k_V的温度修正表达式k_T。研究结果发现：在采样数据范围内BOD₅,TN,TP的出水浓度与HLR成正比,与HRT成反比;SS的出水浓度与HLR成反比,与HRT成正比;BOD₅,TN,TP的去除率与HLR成反比,与HRT成正比;SS的去除率与HLR成正比,与HRT成反比;SS,BOD₅,TN,TP的PLR与HLR成正比,与HRT成反比。SS,BOD₅与TP的k_V与Q,HLR正相关趋势较显著;TN的k_V与HLR趋势正相关不显著,水温变化对SS的k_V影响很小,水温变化对BOD₅,TN,TP的k_V有一定的影响。掌握表面流人工湿地污染物去除与运行参数的相关性及其反应动力学,可为研究湿地系统去除污染物机理以及在不同环境温度下工程设计参数的选择提供了理论基础。     

漂白活化剂TAED在棉针织物煮漂一浴中的应用研究

对漂白活化剂四乙酰乙二胺（TAED）在纯棉针织物的煮漂一浴前处理工艺中的应用情况进行了探讨。通过分析H₂O_{2用量、TAED用量、煮漂时间、煮漂温度等因素对织物白度的影响,以白度为参考指标,确定应用漂白活化剂TAED时的最优工艺条件。〖HJ5mm〗}     

微生物降解含煤油废水的研究

采用微生物法对含煤油废水进行降解,利用HC-404非分散红外测油仪和GC/MS联用仪对降解效果进行跟踪测定。正交试验得出较佳的降解条件为w(C)∶w(N)∶w(P)=360∶6∶1,1L废水中加入表面活性剂0.5mL,H₂O₂为4mL,pH值为8。非分散红外测定结果表明,该条件下烷烃总降解率为91.53%。由降解前后质谱图的对比得出,对正烷烃的降解作用最为明显,其次是支链烷烃,对芳香烃化合物亦有一定程度的降解效果。     

溶胶-凝胶法制备纳米TiO2及其光催化活性的研究

采用溶胶-凝胶法制备纳米二氧化钛,以甲基橙为模型污染物,考察了影响纳米二氧化钛光催化活性的主要因素,并采用TEM,XRD等方法对样品进行了表征。结果表明:具有较高光催化活性的纳米二氧化钛的制备条件是钛酸丁酯、无水乙醇、冰乙酸、水的比例(体积比)为10∶19∶8∶4,500℃下煅烧2h；纳米二氧化钛质量浓度为1g/L时光催化效果最佳；纳米TiO₂具有锐钛矿型晶体结构,平均粒径为10～20nm。     

浅谈金融政策对区域经济发展的影响

一、金融政策区域效应的理论分析 1.统一的法定存款准备金率与货币乘数的地区差异. 货币乘数的大小,影响着货币供给量.货币乘数的一种表达形式是m＝（C/D＋1）/（C/D＋R/D）.其中C是通货,D是存款,R是准备金,C/D是通货存款比,R/D是准备存款比.从准备存款比看：准备存款比R/D是由rd（法定存款准备金率）和 re（超额存款准备金率）构成的,前者是由央行来决定的,后者取决于商业银行.经济发达地区的企业资本边际利润率较高,商业银行对贷款的收回有信心,会增加贷款,超额准备率降低,货币乘数增大;相反,欠发达地区企业的资本边际效率低,为防止不良债权,商业银行相应提高超额准备金率,货币乘数变小.从以上分析可知,在法定存款准备金率统一的情况下,如果超额准备金率存在地区差异,货币乘数在发达与欠发达地区同样存在差异.中央银行要求所有商业银行保持统一的存款准备金率,没有考虑到落后地区乘数较低的情况,抑制了落后地区的货币供给,从而使支持中西部地区经济发展的资金远远小于东部地区,并由此带来区域经济发展的不平衡.     

BiFeO3/H2O2体系降解孔雀石绿染料废水的研究

本文研究了BiFeO3/H2O2体系下孔雀石绿（Malachite green,MG）降解过程中溶液初始浓度、pH值、BiFeO3用量、H2O2的体积分数以及反应温度等因素的影响,确定了该体系降解孔雀石绿的最佳条件。建立了BiFeO3/H2O2体系氧化降解孔雀石绿的动力学方程,为利用非均相类Fenton试剂处理含苯环类有机废水的研究提供了理论依据。     

4，4＇-二环己基甲烷二氨基甲酸甲酯的制备及结构表征

以4,4＇-二环己基甲烷二异氰酸酯（H12MDI）和甲醇为原料,以二月桂酸二丁基锡（DBTDL）为催化剂制备了4,4’-二环己基甲烷二氨基甲酸甲酯（HMDC）。利用熔点测定、红外光谱、元素分析、核磁分析和质谱等手段对得到的两种固体产物A和B进行了表征。结果表明物质A为反-反结构的HMDC;物质B为一混合物,其中不仅含有反-反结构的HMDC,也含有顺-反结构和顺-顺结构HMDC中的至少一种。     

含H2S天然气管道的完整性评价研究

从管道完整性评价的国内外研究进展出发，基于氢浓度和应力共同作用的环境影响，建立了含氢致裂纹管道的完整性评定方法；考虑氢致列裂断裂判据，建立了氢致开裂管的失效评定关系；给出了失效评定图，并给出了这一定输送压力和H2S含量下，含裂纹缺陷管道的安全度和安全范围，以及含H2S管道的极限承压载荷。对管道的安全运行具有重要指导意义。     

基于CEL法的故障齿轮热流固耦合有限元分析

为探究风电机组传动系统中齿轮不同故障热流固耦合下应力演化规律,利用ABAQUS软件,采用CEL有限元法对啮合齿轮进行数值模拟。研究了温度场对齿轮啮合最大接触应力的影响以及热流固耦合下不同损坏程度齿轮在齿宽、齿厚方向最大接触应力值的演化规律。结果表明：引入温度场后不同阶段啮合齿轮的最大接触应力分别增长了20.63%,41.28%,6.13%,说明热力场的介入对应力结果有重要影响;点蚀孔边缘接触应力明显大于正常部位且会扩展,损坏程度越大接触应力值越大;断齿故障在断裂位置接触应力会激增,并且越靠近断裂端接触应力越大且断裂深度越大,最大接触应力也越大;在不同断齿工况下,沿齿厚方向的应力变化趋势一致,断裂程度与齿厚方向上整体应力值呈正相关。CEL有限元法适用于齿轮热流固耦合分析,可以较好地模拟故障齿轮运行状态,为齿轮模拟仿真提供借鉴与指导。     

基于ANSYS Workbench的桥式起重机主梁有限元分析

预测桥式起重机主梁疲劳寿命,需判断主梁应力集中区域,以期为确定应变片检测位置提供理论指导。使用ANSYS Workbench对50/10t桥式起重机主梁进行多工况有限元分析,得到主梁各工况应力云图。分析结果表明,最大应力出现于主梁两端腹板与下盖板连接处以及下盖板两端弯曲处,这些区域易发生疲劳受损。     

高速动车组制动盘热力耦合分析

高速动车在紧急制动工况下,制动盘表面温度分布不均致使制动盘热胀冷缩产生热应力,进而导致制动盘出现热裂纹失效,针对上述问题,以某型号高速动车组拖车制动盘为研究对象,对其在300 km/h紧急制动工况过程开展热力耦合特性研究。综合考虑制动盘材料随温度变化而变化,且制动闸片与制动盘接触面的几何形状和分布对热流密度的影响,建立了基于微元法的摩擦面热流密度计算模型;结合热传导、对流换热和热辐射模型,建立了制动盘的应力计算模型,并对制动盘进行热力耦合分析,得到制动盘的温度和应力分布规律。结果表明,制动过程中制动盘最高温度出现摩擦区域靠近外圈位置处,需采取必要的散热措施;最大应力出现在靠近内圈的散热筋部位,设计时需优化此处结构。新方法构建了基于多物理参数和变梯度微元法的热力耦合模型,有效模拟了高速动车组的紧急制动过程,研究结果可为高速动车组制动盘的选材和结构设计优化提供理论依据。     

Learning CAD at university through summaries of the rules of design intent

The ease with which 3D CAD models may be modified and reused are two key aspects that improve the design-intent variable and that can significantly shorten the development timelines of a product. A set of rules are gathered from various authors that take different 3D modelling strategies into account. These rules are then applied to CAD strategic-knowledge learning methodology and included in 3D CAD modelling exercises for students following the degree in mechanical engineering at the University of Burgos (Spain). The experiment was conducted in two groups with a total of 75 students. The design-intent rules were introduced in the different exercises that the teacher explained in both the theoretical and the practical classes. In addition, a summary of the different design rules in each of the practical exercises was explained in the practical classes in only one of the groups. The experimental results, reported in this paper, tested the influence of these summaries on overall improvements in 3D modelling and on the design-intent variable, which is subdivided into four sections: skeleton, structures, alterations and constraints. The use of the summaries of the design intent rules led to statistically significant improvements in 3D modelling in the experimental group, in comparison with the group of students to whom those summaries were not explained.     

E3201换热器液压胀接接头的非线性有限元分析

考虑换热管和管板材料的应变硬化特性、周围管板孔对胀管影响等因素。建立了E3201换热器液压胀接接头的三维非线性有限元模型。求解该模型能够计算出接触应力、残余接触应力的分布情况，以及胀接压力变化对分布情况的影响趋势．为胀接接头的结构设计和工艺参数优选提供了理论依据。     

The Roles of Marketing and Industrial Design in Discontinuous New Product Development*

Radical or “discontinuous” products based on new technological breakthroughs are playing an ever‐increasing role in the success of firms. However, little research has been conducted that investigates the roles of marketing and industrial design (ID) in the development of these types of products. Further, past research has tended to overlook the role that industrial design, and the impact of the marketing‐industrial design interaction, can have on the development of discontinuous new products. Frequently, the term design is used broadly or is equated with engineering; thus, while the marketing–research and development (R&D) interaction is studied, the marketing–ID as well as the industrial design–R&D relationships are not considered. This article examines the roles of marketing and industrial design in the product development process for discontinuous innovations. Specifically, questions concerning how and the degree to which marketing and industrial design are integrated into the development process are investigated. The investigation employs multiple methods, or triangulation, in order to secure an in‐depth understanding of the roles of these disciplines. In the course of examining these questions, key factors influencing industrial design and marketing involvement are identified and preliminary models are examined. The research, which was conducted in two phases, employed a mixed‐method, multiple sample design. The methods used included a survey, field observation study, and depth‐interviewing. Data were collected from three different samples: R&D managers, project team members (including personnel from various disciplines—marketing, R&D, industrial design, engineering, etc.), and industrial design managers. The use of the different data sources and sampling of various groups of managers was employed in order to provide a rich context for investigating the research questions of interest. In addition, a preliminary analysis of factors (e.g., degree of product discontinuity, product innovation objectives, process discontinuity, process formality) identified in the first phase was conducted, and these relationships were explored further in the second phase of the research. Findings across the two phases of this research suggest that the development of discontinuous new products involves a process that is different from more conventional new product development—particularly as it concerns the roles of marketing and industrial design. The high degree of discontinuity inherent in such projects, along with the strong R&D orientation often surrounding them, results in delayed involvement of marketing and ID, as well as altering their roles in the new product development (NPD) process. Factors such as the degree of product discontinuity (DPD), process discontinuity (PCD), and process formality (PF) seemed to exert a differential influence on the involvement of marketing and ID. Although their roles and involvement are altered in discontinuous new product development, this research suggests that marketing and ID roles in this context involve increased challenges with respect to validation of key assumptions and product application directions. Additionally, managers operating in this development context need to explicitly consider the influence of factors such as discontinuity level in undertaking NPD projects with respect to how it affects the execution of industrial design and marketing activities.     

地下综合管廊混凝土爆灰检测及加固

针对某市钢筋混凝土地下综合管廊的现浇顶板、侧壁出现的混凝土爆灰质量缺陷,为确保管廊结构的安全使用,采用钻心法、超声波法、沸煮试验、爆灰物质的化学成分分析等检测方法,对爆灰现象进行了检测。结果显示,混凝土中存在的块状氧化钙与水熟化后体积增大1倍~2.5倍,使得混凝土在强度未达到设计抗拉强度前在块状氧化钙体积膨胀应力作用下被拉裂,导致了此类质量缺陷的发生。分析了质量缺陷对管廊结构的影响,并对管廊结构进行了加固设计及处理,满足了结构的正常安全使用要求。研究结果可为类似爆灰缺陷的设计及处理提供参考。     

多夹层蜂窝纸板压溃性能分析

通过对夹层数不同的蜂窝纸板进行压溃性能分析,得到夹层数对其抗压性能的影响。首先利用三维软件建立在总厚度一定,且纸芯边长相同情况下的4种不同夹层数的蜂窝纸板分析模型,在有限元软件中分析压溃过程,并得到压力变化曲线,为蜂窝纸板制品,尤其是缓冲垫的结构设计提供帮助。