Net pressures on the roof of a low-rise building with wall openings

This paper deals with an investigation of the characteristics of net pressures on two significant roof areas of a low-rise building with two different dominant wall openings. Wind tunnel boundary layer studies were conducted on a corner and a gable-end roof area of a 1:50 geometric scale model of the Texas Tech University (TTU) test building with a corner and a central wall opening. Mean and peak pressure coefficients, RMS values for the pressure coefficient fluctuations about their mean, as well as roof external pressure—internal pressure correlation coefficients were obtained for the entire 360° wind azimuth range. Frequency domain studies were also conducted for a few selected point roof pressure situations from which the frequency-dependent roof external pressure—internal pressure phase difference functions, root coherence functions and the spectral density functions were obtained. The results show that the mean, RMS and peak net pressure coefficients are particularly enhanced relative to the coefficients for the roof external pressure in the ±50° wind range. Zero-time-lag correlation coefficients of up to −0.64 were obtained in agreement with results from past studies, while root coherence values of up to 0.7 were also recorded. It is demonstrated that the provisions of both the Australian/New Zealand wind loading code—the AS/NZS1170.2:2002, and the American wind loading code—the ASCE7-02, are sometimes non-conservative in the prediction of mean and peak net roof pressure coefficients. These are believed to be due to non-conservative internal pressure coefficients allowed for in these codes.     

Synthesis of derivatives of Naphtol AS containing polar groups and modification used for C.I. Pigment Red 57

The synthesis of derivatives of Naphtol AS containing polar groups (–COOH, –SO₃H) and factors affecting the reaction have been studied. Four derivatives of Naphtol AS containing –COOH or –SO₃H groups in the 3- or 4- position of the phenyl ring were synthesized. Derivatives of Naphtol AS as the second coupling component were used in mixed coupling and the effect of its added amount on the colour strength, hue, flowability and dispersing extent (in water) of pigments was studied.     

基于Flash平台化工仿真实训动画设计

目前,随着信息化教学的稳步推进,计算机多媒体技术及交互式动画技术的不断发展,采用计算机来制作模拟实验在教学中的应用越来越广泛。通过一化工类课程实训单元操作实例,以Flash平台为依托,简单而巧妙地解决了实训操作过程中的顺序控制和交互控制等难题,其设计思想和方法可供其它如机械、仪表、电器类专业实训、组装等仿真模拟设计与实现借鉴和参考。     

智能型高压断路器电子计数器

针对目前变电站断路器的使用情况进行分析,提出并设计出一种能有效评估断路器寿命及判断分、合闸情况的智能计数器,为智能变电站的建设提供基础数据依据。     

组合实验设计用于黄曲霉毒素污染控制的研究

为控制黄曲霉毒素主要产生菌寄生曲霉 AS3.4407在粮食储藏环境中的产毒污染,采用组合实验设计策略,考察了五个模拟环境因子对菌株产毒的影响。首先,利用 Plack-ett-Burman 试验筛选出三个对毒素产量影响显著的因子(转速、温度、pH),在此基础上,采用CCD 实验设计法(Central Composite Design,CCD)研究了这三个因子对寄生曲霉 AS3.4407产毒影响的交互作用,并根据毒素曲面方程和二次多项回归方程得到该菌的最低产毒条件。在环境通风良好(转速240rpm),储藏温度较低(18℃),pH 为弱碱性(pH8)条件下,寄生曲霉AS3.4407产毒量最低,验证试验证实了该方程的预测值与实际值之间具有较好的拟合度。为粮库采取相应措施,改变储藏环境条件以降低毒素污染提供了很好依据。     

配用废亚麻原料生产高级卷烟纸

通过小型实验，提出采用碱性亚硫酸盐（ＡＳ）法，蒸煮麻骨含量３０％，左右的废亚麻原料，再经过漂白，打浆后，所得纸浆质量与大麻接近，并在生产实践中代替大麻原料生产高级卷烟纸，降低了成本，提高了经济效益。     

聚丙烯酰胺凝胶电泳研究硫酸铵盐析分离猪血清IgG

通过聚丙烯酰胺凝胶电泳对硫酸铵盐析分离猪血清G型免疫球蛋白进行了研究，结果显示pH值7．4时，猪血清IgG主要沉淀区间为硫酸铵饱和度25-40％，10倍稀释猪血清IgG最佳硫酸铵沉淀参数为：pH值7．4，硫酸铵饱和度37％，此时IgG得率为80．5％，纯度为72．9％。沉淀的血清蛋白中还含有约12％白蛋白和9％其它γ-球蛋白。沉淀时IgG活性保持不变。     

AS／400的2000年问题的探讨

２０００年问题是ＩＴ行业要迫切解决的问题。分析了ＡＳ／４００的２０００年问题，并且给出了一个可行的ＡＳ／４００ ２０００年问题实施方案。     

Z跟踪技术下C/A码与P（Y）码伪距的精度比较

由于AS(Anti-Spoofing)政策的实施,给广大GPS非特许用户的精密测距和高精度导航、定位带来了不少困难,Z跟踪技术就是消除或减弱AS政策影响的一个有效方法。该文首先阐述了利用Z跟踪技术进行保密P(Y)码伪距测量的基本原理,然后采用自行编制的基于精密星历的单点定位程序,利用IGS跟踪站观测数据进行了计算,对C/A码与P(Y)码伪距的精度进行了比较,证实了Z跟踪技术的有效性。     

色酚AS偶氮颜料（二）

色酚AS类颜料是由2-羟基-3-萘酰胺化合物作为偶合组分与取代基芳胺重氮盐偶合制得的偶氮颜料,主要给出红色谱,颜料分子中因含有甲酰氮基（-CONH-）具有良好的耐溶剂性能.文中介绍色酚AS偶氮颜料的发展历史、化学性质及生产、性能、应用,并介绍了目前市场上的二组商用色酚AS偶氮颜料,色酚AS偶氮颜料中红1 12、146以及170在传统工业领域的红色谱中具有相当的市场份额.