Cure reaction for modified diallylbisphenol A/diaminodiphenylsulfone/bismaleimide

The glass‐transition temperature as a function of curing conversion for a modified diallylbisphenol A/diaminodiphenylsulfone/bismaleimide (BMI) resin was investigated at different temperature regimes and modeled using a modified Di Benedetto equation. Although the relationship between the glass‐transition temperature and conversion of the BMI system conforms to the Di Benedetto equation for α < 0.6 and at lower cure temperatures, at higher cure temperatures the results deviated significantly from the equation; thus, it was an inadequate model for the system. Fourier transform IR analysis showed that the major crosslinking reactions did not occur during cure for the modified BMI at and below 150°C. However, as the cure temperature was increased, the crosslinking reactions responsible for 3‐dimensional network structures became more dominant. At 190°C the C? N? C_stretch vibration of the uncured maleimide ring converted into succinimide rings in the curing process. Simultaneously, a decrease was observed for the absorbance bands of ? C? H_bending (maleimide). The higher cure temperatures induced a significantly faster initial crosslinking rate and also resulted in a shorter period of time after which further crosslinking was retarded, because the increase in the crosslinks also physically slowed further crosslinking activity. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 227–235, 2002     

Design aspects of planar and conventional SMPS transformer: a cost benefit analysis

The intent of this paper is to design a high-frequency transformer that is to be incorporated into the DC/DC pulsewidth-modulated switch-mode power supplies by two different technical approaches: a conventional wound-coil magnetic using copper wires, and a planar magnetic with layered copper tracks on laminated printed circuit board. Comparisons will be made between the two approaches in terms of profile: mounting height and surface area, and performance: power losses and efficiency. Other indicators like temperature rise and leakage inductance that causes electromagnetic interference, and cost, materials, and process fluency are also to be looked into. A sandwiched configuration for primary and secondary windings is proposed for the planar type. Issues arising and typical phenomena encountered will be discussed in detail. Primarily, the dominating factor in performance, cost effectiveness, or circuit compactness that restrains the choice of a particular type is to be evaluated.     

汽油辛烷值智能调合系统

采取一种能够在线学习、不断提高、建立一系列模型的策略，提出了一种具有学习功能的汽油辛烷值智能调合系统。该系统可以根据成品汽油辛烷值指标、生产成本和市场价格等因素提供一个较好的油品调合调度方案。实际应用结果表明，利用参数学习的方法计算调合汽油辛烷值是可行的。     

云龙水库大坝表面变形观测资料分析

1工程概况云龙水库是昆明市掌鸠河引水供水工程的水源工程,位于昆明市西北部禄劝县的云龙乡岔河村附近,距昆明市区约86km。大坝坝址选在金沙江水系二级支流掌鸠河上游峡谷河段内,初期规模正常蓄水位2087.97m,校核洪水位2091.98m;终期规模水库正常蓄水位2089.67m,设计洪水位2092.59m,校核洪水位2093.58m。初期规模总库容4.48亿m3,终期规模总库容4.84亿m3,属大(2)型水库工程,工程等别为Ⅱ。水库枢纽建筑物由大坝,泄洪、导流隧洞,引水隧洞,溢洪道等组成。除溢洪道按初期规模兴建外,其余枢纽建筑物均按终期规模兴建。泄洪、导流和引水建筑物布置…     

Inventory routing with continuous moves

The typical inventory routing problem deals with the repeated distribution of a single product from a single facility with an unlimited supply to a set of customers that can all be reached with out-and-back trips. Unfortunately, this is not always the reality. We introduce the inventory routing problem with continuous moves to study two important real-life complexities: limited product availabilities at facilities and customers that cannot be served using out-and-back tours. We need to design delivery tours spanning several days, covering huge geographic areas, and involving product pickups at different facilities. We develop an innovative randomized greedy algorithm, which includes linear programming based postprocessing technology, and we demonstrate its effectiveness in an extensive computational study.     

Nash equilibrium bidding strategies in a bilateral electricitymarket

This paper examines bidding strategies in a bilateral market in which generating companies submit bids to loads. A load accepts electricity delivery from the generator with the lowest bid at its bid price as long as this price is not higher than the load's willingness to pay. Necessary and sufficient conditions of Nash equilibrium (NE) bidding strategy are derived based on a generic generating cost matrix and the loads' willingness to pay vector. The study shows that in any NE, efficient allocation is achieved. Furthermore, all Nash equilibria are revenue equivalent for the generators. Based on the necessary and sufficient conditions, this problem is formulated as an optimal assignment problem. Network optimization techniques are applied to calculate NE bid prices for the generators     

TEM study of PLZT ceramics

The microscopic structures of PLZT(7.9/70/30 and x/65/35, x = 7 or 8) ceramics were studied by means of transmission electron microscopy. The presence of micro-regions in PLZTs was first verfied.     

乳化炸药混装车水孔爆破的优越性

该文分析了应用袋装炸药装填水孔爆破产生拒爆、"冲天炮"、根底偏高和爆破效果差等问题,然而应用乳化炸药混装车装填水孔可以解决这些问题,并且爆破后具有根底平整、大块率低、毒气少和综合效益高等优点.以三峡永久船闸旁侧泄水箱涵工程和江苏田湾核电站工程为例进行了分析.     

Analyses of the practical adhesion strengths of the metal/polymer interfaces in electronic packaging

There is a plethora of techniques to measure the adhesion strength of metal/polymer interfaces. However, the practical adhesion strength, which is the work done in separating the film from the substrate (or one film from another), is very sensitive to the test methods and the mechanical effects, such as the residual stress, thickness and mechanical properties of the layers, strain rate, and phase angle. Deriving intrinsic-adhesion properties of the interfaces, which are independent of such parameters, from the practical adhesion-strength measurements is a formidable task. In the present work, data from the three commonly used adhesion tests; pull-out, 90°-peel, and T-peel tests are compared with the intrinsic-adhesion properties of the interface, such as the interface-fracture toughness or the interface-fracture energy, and their implications are discussed. Material systems analyzed were Cu-based lead frame/epoxy-molding compound (EMC) and Cu/Cr/polyimide.     

PP-g-MAH对PA6/PP/TLCP三元共混物的增容改性作用

研究了PP-g-MAH对PA6／PP／TLCP三元共混体系的增容作用以及对共混物流变性能和力学性能的影响。通过共混物的DSC、SEM、POM、流变性能和力学性能测试，结果表明，PP－g-MAH对共混体系有明显的增容作用，共混物的力学性能（拉伸强度和冲击强度）得到提高；由于TLCP的加入，共混物的熔体粘度大大低于PA6的熔体粘度。