A Two-Dimensional Approach to Systems Development

Abstract

Although many variables can contribute to the failure of a systems development project, the use of the traditional f one-dimensional systems development life cycle approach is often a major factor in the failure of such an effort This article describes an alternative method— the two-dimensional approach to systems development— and discusses why IS managers should consider adopting this new development approach.     

108m~3聚合釜运行总结

介绍了在108 m3聚合釜生产过程中脱氧塔、助剂配制、聚合进出料、反应监控、压缩回收、汽提、干燥等生产环节的控制要点。阐述了试生产过程中出现的粘釜、堆床等异常情况产生的原因及采取的预防措施。     

印制PVC墙纸用(甲基)丙烯酸酯乳液光油

考察了聚合工艺、N-羟甲基丙烯酰胺(NMA)，甲基丙烯酸二甲氨基乙酯(DMAEMA)、甲琏丙烯酸甲酯(MMA)及乳化剂等原材料的用量对印制PVC墙纸用乳液光油及涂膜性能的影响。研究结果表明采用改进型半连续种子乳液聚合工艺能制得粒径为35．6nm，粒径分散性为0．133的乳液，DMAEMA能明显抑制合成含羧酸基和N-羟甲基的聚合物过程中N-羟甲基的自缩聚反应．提高涂膜性能；当ω(NMA)=2％～4％．ω(DMAEMA)=0．5％～1％．ω(MMA)=60％～70％，ω(乳化利)=2%～4％时制得的罩光油在PVC底材表面具有优异的光泽度、润湿性、附着性以及耐高温热粘性。     

A sandwich enzyme-linked immunosorbent assay for κ-carrageenan determination

High titre antisera to κ-carrageenan were produced by immunisation of rabbits and guinea pigs with K-carrageenan. These antisera, rabbit serum as a capture antibody and guinea pig serum as a detector antibody, were used in a sandwich enzyme-linked immunosorbent assay. The range of determination of K-carrageenan was from 16 to 256 ng ml^?1 in the assay. The antisera showed no cross-reactivity with six thickeners. The assay was developed for application to foods such as jelly and custard pudding and demonstrated many advantages including high sensitivity, technical simplicity and the minimal requirement for food sample preparation before assay.     

水田改旱田高产新探讨

长期连作水田土壤粘朽，冷凉，不利水稻高产，更不利水田改旱田，三江原有“水改旱瞎一半”之戒律，只有加强排水，采取秋耕，深松，加上促早熟等措施，才能创高产，由于生态环境改变，可送减少施用化肥和农药，实现低耗优质，减少污染，其实“水旱作”是我国优良传统农业技术，也是今后优质高产高效可持续农业发展方向。     

一种豆花蘸料的制备及其挥发性物质研究

以豆花蘸料配方为研究目标,在单因素、正交实验的基础上结合感官评价、方差分析对配方进行优化,通过GC-MS分析最佳配方的挥发性物质。实验结果表明,以郫县豆瓣205 g、花椒粉26 g、八角粉6 g、基础油230 g、生姜20 g、精盐4 g、料酒5 g、鸡精5 g、白糖4 g、大蒜10 g、胡椒粉4 g、酱油9 g、蚝油5 g制备的豆花蘸料感官评分最高。GC-MS分析结果表明,豆花蘸料共检测到47种挥发性物质,烯烃类19种,醚类7种,醛类7种,醇类6种,酯类4种,呋喃类3种,酸类1种,占总挥发物质的96.242%。烯烃、醛类、醇类和醚类物质对豆花蘸料风味的形成具有重要意义,可能是蘸料的主要特征风味物质。     

管袋充填高含粘量泥浆的高效脱水方法

针对土工管袋充填高含粘量泥浆时脱水固结慢的问题,通过室内试验研究了土颗粒沉淀规律及充填土料含粘量、管袋袋布等效孔径、管袋袋壁的拍打扰动等对脱水效率的影响,开发出一种管袋充填高含粘量泥浆时高效脱水的施工方法,即对于粘粒含量达到20%的充填泥浆,以低于30%的浓度进行充灌有利于粗细土颗粒分离;管袋顶部排水面采用大等效孔径的编织布制作,并在充灌后静止20min待粗颗粒基本沉淀结束后以时间间隔小于1min的频率均匀拍打袋壁,可以使处于悬浮状态的粘粒和部分粉粒在短时间内排出管袋。利用该方法充灌后10h管袋底部孔隙水压力消散程度可达到75%,可以继续上层管袋的充灌。     

阳极氧化用5052铝合金基材轧制表面质量控制浅析

分析了热连轧和冷轧过程中影响5052铝合金阳极氧化效果的主要表面缺陷,如黑条、压过划痕、粘伤、印痕和黑点等产生原因,并制定了相应的解决措施。     

A simple approach to fabricate sticky superhydrophobic polystyrene surfaces

We present a facile method for the fabrication of a sticky superhydrophobic polystyrene surface using ethanol as the non-solvent. The obtained surface shows the hierarchical textured morphology as well as the multiple scales of roughness and large numbers of microspheres. Without any chemical modification, the prepared polystyrene surface exhibits sticky superhydrophobicity with a high equilibrium contact angle of 153°. Interestingly, a water droplet on the surface cannot move at any tilt angle even when the substrate is turned upside down. The mechanism of the fabricated surface with high adhesion is discussed in detail. Moreover, the obtained polystyrene surface exhibits the strong adhesion to the liquid droplets of pH value from 1 to 14.     

减振胶带在分体式空调器室外机的应用研究

目前空调器室外机减振降噪材料普通采用丁基橡胶阻尼块,本文旨在研究一种新型的阻尼材料——铝箔减振胶带,应用于室外机减振降噪,为空调器提供多一种解决振动和噪音的方法。