关于热水小时变化系数Kh内插法计算的探讨

在GB50015--2003（（筑给水排水设计规范》（2009年版）的具体应用过程中，发现热水系统小时变化系数鼠的计算方法有待商榷，特提出来进行分析与探讨。提出了鼠计算的建议性方法，并建议“新版建水规”中补充用水定额取高（低）值、使用人（床）数少（多）及用水定额介于规范规定值之间，但使用人（床）数小于等于规范规定的下限值（或者大于等于规范规定的上限值）时，‰该如何取值或者计算；建议“新版建水规”中补充二元内插法计算Kh所需要的表格以方便广女工程设计人葡杏阅     

Effects of CMAS penetration on the delamination cracks in EB-PVD thermal barrier coatings with curved interface

During the high-temperature operation of electron beam physical vapor deposited (EB-PVD) thermal barrier coating (TBC), the penetration of environmental calcium-magnesium-alumina-silicate (CMAS) compositions into the ceramic top-coat would affect the growth of delamination cracks. In this work, the effects of CMAS penetration on the delamination cracks in EB-PVD TBC with curved interface are investigated by finite element analysis. In the numerical model, the curved interface evolves as the cyclic displacement instability of the thermally grown oxide (TGO) layer. The penetration of CMAS into the columnar gaps of EB-PVD TBC mainly increases the in-plane modulus of TC layer. It is demonstrated that, with the increase of in-plane modulus in an intact TC, the level of tensile stress, which mainly occurs in the region above the curved interface and responsible for initiating the delamination cracks, presents a decrease; meanwhile, the level of shear stress, which mainly occurs in the region at the periphery of the curved zone to drive the delamination crack when it propagates into this region, presents a increase. Furthermore, the calculation of the strain energy release rate shows that, for the crack located above the curved interface, the increase of in-plane modulus in TC layer can prevent the accumulation of strain energy release rate, and therefore make it more difficult for delamination initiation. However, once the crack propagates into the flat periphery, CMAS penetration would begin to enhance its growth.     

利用PVT分析仪测定PS的热膨胀系数,等温压缩系数和热压系数

利用实验测得的ＰＶＴ数据直接计算出聚苯乙烯（ＰＳ）的热膨胀系数α,等温压缩系数β和热压系数γ随温度和压力的变化关系,与同样从ＰＶＴ数据获得的Ｔａｉｔ方程计算出的α、β和γ结果比较,说明了Ｔａｉｔ方程在使用上存在一定的局限性。     

近红外光谱结合偏最小二乘法测定复方阿司匹林/双嘧达莫成分含量

采用近红外漫反射光谱分析技术对复方阿司匹林/双嘧达莫药物的有效成分进行测定,结合偏最小二乘(PLS)法分别建立了复方药物有效成分双嘧达莫及阿司匹林的相关模型,结果显示,复方阿司匹林/双嘧达莫中双嘧达莫PLS模型的相关系数R为0.99921,交互验证均方根误差(RMSECV)是0.00170,预测集均方根误差(RMSEP)是0.00291;复方中阿司匹林PLS模型的R为0.99517,RMSECV为0.000810,RMSEP为0.000831。由此表明,所建立的模型预测性能良好,均在误差范围内,说明方法准确可靠,可以用于实际生产中的在线控制。     

Estimation of true biomass energetic yield and maintenance coefficient with errors in the variables

Simple regression analysis is based on the least square of residual errors. To use this method, an independent variable which is observable without error is assumed to exist. For most analyses, the assumption is normally made without realising the implications. The present study demonstrates how parameters may be estimated with the assumption of error in all measurements. Data sets involving batch/fed-batch cultivation of Candida utilis were analysed using a statistical approach with error in variables for the estimation of true biomass energetic yield and maintenance coefficient. This approach requires replicated measurements. For linear systems, such as in chemical/biochemical processes, replicated measurements are sometimes possible or there are physical/physiological reasons to group the observations into clusters. When clusters of replicated measurements are not available, the cluster analysis technique may be used to identify groups of near-replicated data points. The procedure yielded similar results to those obtained by the ordinary least squares procedure for consistent data. However, for data of poor quality (especially data with large errors in the independent variable), the disparity between the two procedures was more significant.     

Re-examination of the relationship between packing coefficient and thermal expansion coefficient for aromatic polyimides

The existence of a possible relationship between molecular packing coefficient and thermal expansion coefficient for various aromatic polyimides was investigated. Rod-like low-thermal-expansion polyimides without side groups were seen to have very high packing coefficients, pointing to free volume as a factor in lowering their thermal expansion coefficients. But the small packing coefficients for low-thermal-expansion polyimides with side groups indicated that this was not so. Also, even if the large packing coefficients tended to increase the Young's moduli for these polyimides without side groups, the rod-like polyimides with side groups have small packing coefficients and large Young's moduli. The polyimides with low packing coefficients were found to have very small diffusion coefficients for water vapour.     

铲车匹配条件下铲作业率的计算

在铲、车同时出动的概率分布基础上,结合具体采、剥工艺系统,用随机向量和排队分析法,作出铲、车同时出动条件下铲工作面至少有1台车的概率之和,该概率和即代表铲作业率。此外还阐述了铲作业率的主要影响因素。     

An investigation of the dependence of penetration on the temperature and composition of paraffin waxes

A general penetration/temperature function for paraffin waxes was derived for the temperature range from 25 °C to 40 °C. In this function each individual temperature is entered as the difference to the theoretical melting temperature of the n‐alkanes of the mixture. The theoretical melting temperature of the n‐alkanes was determined based on the results of a gas chromatography (GC) analysis. The dependencies of the parameters of this function were investigated on the basis of the GC and differential scanning calorimetry data of the slack wax, paraffin waxes and the urea adducts obtained from paraffin waxes with different gradations. Particularly the influence of crystallinity as a link between composition and physical properties was considered in this context. Crystallinity was defined as the ratio of the melting enthalpy of the respective product to the melting enthalpy of the n‐alkanes it contained, with ideal crystallisation assumed. It was demonstrated that, in addition to crystallinity, the chain length of the n‐alkanes also plays a decisive role in the penetration/temperature behaviour.     

有机磷农药对神经毒性酯酶活性抑制作用与其分配系数关系的研究

本文以白色成年莱亨母鸡为材料，进行了不同类型的有机磷农药以ＬＤ５０剂量处理鸡４８小时后取其脑组织匀浆液作酶源，测定其ＮＴＥ活性。在反应体系中分别加入对氧磷及对氧磷与氟丙胺磷混合液，以差异抑制法测定出反应终产物在５１０纳米处的ＯＤ值，以每分钟毫克蛋白所分解底物戊酸苯酯生成产物苯酚的量表示ＮＴＥ的活性。用反相液相色谱法测得标样化合物的保留时间（ｌｏｇＴＲ）与其正辛醇／水的分配系数（ｌｏｇＰ）呈线性关系。因而预测了２２种有机磷化合物的分配系数。发现某些有机磷化合物的分配系数大，其对ＮＴＥ活性的抑制作用也较强，但无明显的线性关系。     

Evaluation of chloride penetration in high performance concrete using neural network algorithm and micro pore structure

Chloride attack is one of the major causes of deterioration of reinforced concrete structures. In order to evaluate the chloride behavior in concrete, a reasonable prediction for the diffusion coefficient of chloride ion, which governs mechanism of chloride diffusion inside concrete, is basically required. However, it is difficult to obtain chloride diffusion coefficients from experiments due to time and cost limitations.In this study, a numerical technique for chloride diffusion in high performance concrete (HPC) using a neural network algorithm is proposed. In order to collect comparative data on diffusion coefficients in concrete with various mineral admixtures such as ground granulated blast-furnace slag (GGBFS), fly ash (FA), and silica fume (SF), a series of electrically driven chloride penetration tests was performed. Seven material components in various mix designs and duration time are selected as neurons in a back-propagation algorithm, and associated learning of the neural network is carried out. An evaluation technique for chloride behavior in HPC using the obtained diffusion coefficients from the neural network algorithm is developed based on, so-called, Multi-Component Hydration Heat Model (MCHHM) and Micro Pore Structure Formation Model (MPSFM). The applicability of the developed technique is verified by comparing the analytical simulation results and the experimental results obtained in this study. Furthermore, this proposed technique using the neural network algorithm and micro modeling is applied to available experimental data for verification of its applicability.