当代中国建筑实践中的理性主义

区别于现代主义时期的理性主义,当代建筑创作中渗透的理性主义思想内涵更为全面和深刻。本文阐释了理性主义在当代中国盛行的原因。结合国内建筑案例,探究理性主义在我国当代建筑创作实践中的表现特征,得出了当代理性主义建筑创作对形态极简性的追求、对技术真实性的关注、对功能逻辑性的推理、对经济合理性的诉求四个表现特征。希望借此研究,完善当代建筑设计的理论成果并指导我们今后的建筑创作实践。     

深圳海关科技信息业务综合楼

深圳海关科技信息业务综合楼位于福田中心区西侧．总建筑面积80000m^2，由主楼和附楼两部分组成。主楼为科技信息大楼．高9880m．共22层．内设办公室、会议室、计算机网络中心、图书馆、档案室以及海关成果展厅等。附楼为报关大楼．高2280m．共4层．其中首层为报关大厅和接待厅．二层设有海关职工餐厅及雅座，三层为报告厅（528座）。主楼和附楼之间以玻璃连廊相连。     

JN型早强减水剂的研制与应用

为了在低温潮湿的气候条件下改善混凝土的性能，加快施工进度，最明显的效果是在混凝土中添加早强减水剂。本文介绍了ＪＮ型早强减水剂的良好技术性能、多方面的实际应用效果和所获得的显著经济效益。     

A novel Kalman filter for combining outputs of MEMS gyroscope array

In this paper, a Kalman filter for combining outputs of a gyroscope array is presented to improve the accuracy of microelectromechanical system (MEMS) gyroscope. A theoretical mathematical model for the accuracy improvement is described. Especially, a discrete-time filter is designed by solving the covariance differential equation with an analytic solution. Performances of presented filter are analyzed by the simulations. Finally, a developed system consisting of six-gyroscope array is implemented to test the performance of the Kalman filter. The experimental results showed a noise density of 0.03°/s/√Hz for the combined rate signal compared to the 0.11°/s/√Hz for the individual gyroscope in the array. The analysis of results measured from Allan variance demonstrated a bias instability of 17.2°/h and angular random walk of 1.6°/√h, whereas the corresponding values for the individual gyroscope is 62°/h and 6.2°/√h, respectively. It proved that the presented approach is effective to improve the MEMS gyroscope accuracy.     

Isolation and identification of ent-kaurane-type diterpenoids from Rabdosia serra (MAXIM.) HARA leaf and their inhibitory activities against HepG-2, MCF-7, and HL-60 cell lines

A phytochemical investigation was conducted on Rabdosia serra leaf in this work. A new ent-kaurane-type diterpenoid named 6β,14α-dihydroxy-1α,7β-diacetoxy-7α,20-epoxy-ent-kaur-16-en-15-one, together with 6 known compounds were identified, including parvifolin G, effusanin E, lasiodin, nodosin, β-sitosterol, and stigmasterol. It was the first time that parvifolin G and effusanin E were found in R. serra. The assay of inhibition activity against HepG-2, MCF-7, and HL-60 cell lines indicated that 10 compounds (including rosmarinic acid, methyl rosmarinate and pedalitin which were isolated previously), except parvifolin G and stigmasterol, exhibited cytotoxicity against the tested tumour cells. The tumour inhibitory effects of ent-kaurane-type diterpenoids (except parvifolin G) were more effective than those of sterols and phenolics. Both 6β,14α-dihydroxy-1α,7β-diacetoxy-7α,20-epoxy-ent-kaur-16-en-15-one and lasiodin (IC₅₀ < 5 μM) displayed strong cytotoxicity against the tested tumour cells, indicating the potential for new chemotherapeutic drugs.     

A survey on occurrence of thermophilic bacilli in commercial milk powders in China

Twenty-two milk powders including infant formula milk powders and whole milk powders collected from different manufacturers in China were examined for the presence of contaminated thermophilic bacilli. The thermophilic isolates were grouped by whole cell protein profiles, and representative strains of each group were further identified by analyzing partial 16S rDNA. 80.5% of all 801 isolates were identified as Bacillus licheniformis, Anoxybacillus flavithermus and Geobacillus stearothermophilus. The most dominant strain was B. licheniformis L1, which accounted for 27.8% of all isolates and appeared in eighteen of twenty-two milk powders. Furthermore, the inactivation effect of conventional heat treatments that were widely used in industry for milk powder was tested on ten representative strains. The three pasteurization processes did not show inactivation effect on most strains, but in some cases even activated thermophilic spores. The UHT process efficiently inactivated both thermophilic vegetative cells and spores.     

双管自立式钢结构烟囱设计简介

本文就某电厂采用的新型烟囱结构形式——双管自立式烟囱结构进行了简要的介绍。双管自立式烟囱外形美观且受力简洁,既能满足功能上的要求,又能成为电厂的一大亮点。     

Modified k-ω model using kinematic vorticity for corner separation in compressor cascades

A new method of modifying the conventional k-ω turbulence model for corner separation is proposed in this paper. The production term in the ω equation is modified using kinematic vorticity considering fluid rotation and deformation in complex geometric boundary conditions. The corner separation flow in linear compressor cascades is calculated using the original k-ω model, the modified k-ω model and the Reynolds stress model(RSM). The numerical results of the modified model are compared with the available experimental data, as well as the corresponding results of the original k-ω model and RSM. In terms of accuracy, the modified model, which significantly improves the performance of the original k-ω model for predicting corner separation, is quite competitive with the RSM. However, the modified model, which has considerably lower computational cost, is more robust than the RSM.     

超高压装置在食品工业中的应用

超高压装置是高压食品研制、开发、生产的关键设备．能否提供性能优良、价格相对适中的高压装置是高压食品产业化的关键．本文系统介绍了食品高压处理的方法及高压处理装置,并就高压技术在食品工业中的发展方向提出了几点建议．     

Reversible performance loss induced by sequential failed cold start of PEM fuel cells

This study correlates the post start cell performance and impedance with the cold start process in the subzero environment. The sequential failed cold starts are deliberately conducted as well as the start at small current density. Here the failed cold start means the cell voltage drops to or below zero within very short time during the start process. It is found that there are reversible performance losses for the sequential failed cold starts, while not obvious degradation and no recovery happen for the start at small current density. Using the thin film and agglomerate model, it is confirmed that this is due to the water blocking effect. Comparing the results from different start processes, a model with respect to the shifting of reactive region within the catalyst layer is applied to explain that the reversible performance loss is associated with the amount of the generated water or ice and the water location or distribution during cold start. The relationship of the cold start performance at high current density and the pore volume in the catalyst layer is also discussed.