Lead-acid and lithium-ion batteries for the Chinese electric bike market and implications on future technology advancement

China has been experiencing a rapid increase in battery-powered personal transportation since the late 1990s due to the strong growth of the electric bike and scooter (i.e. e-bike) market. Annual sales in China reached 17 million bikes year⁻¹ in 2006. E-bike growth has been in part due to improvements in rechargeable valve-regulated lead-acid (VRLA) battery technology, the primary battery type for e-bikes. Further improvements in technology and a transition from VRLA to lithium-ion (Li-ion) batteries will impact the future market growth of this transportation mode in China and abroad.     

Optimisation of foam‐mat drying of yoghurt and properties of powdered yoghurt

Foam‐mat drying was optimised by studying the effects of different concentrations of soy lecithin on foam density and foam expansion of yoghurt. Sample thickness was studied by drawing drying and moisture ratio curves during drying in electric tray dehydrator at 58–63 °C. Prepared powder was analysed to study the impact of foaming agent on yoghurt powder. Evaluation of bulk properties was done to reduce storage and transportation volume. Wettability, water absorption capacity and insolubility index were determined to study effects on functional properties. Scanning electron microscope was performed for studying surface properties. No significant changes were observed in bulk properties, but treatment significantly affected functional and surface properties.     

Preparation of electrospun electroactive POMA fiber mats

A neat electroactive freestanding non‐woven mat was first prepared from poly(o‐methoxyaniline) (POMA) using an electrospinning technique without blending or grafting. Results showed that a continuous fibre structure was obtained for high weight‐average molecular weight M?_w of POMA, i.e. POMA forced to become more soluble when synthesized in the presence of CaCl₂ and an alkoxyl‐ring‐substituted structure. By performing gel permeation chromatography and viscosity tests, we found that M?_w ≈ 69 000 g mol^?1 and concentrations were critical to the formation of beads or fibres. The electrospinning parameters that cause morphological changes were found by scanning electron microscopy. By comparing these with governing parameters such as viscosity, feeding rate, collector distance and applied voltage, uniform POMA fibres were produced from 5 wt% POMA solution at 20 kV with a feeding rate of 0.02 mL min^?1 and nozzle‐to‐collector distance of 12 cm. In addition, the electroactivity and mechanical strength of the neat electrospun non‐woven mats were studied by electrochemical cyclic voltammogram and dynamic mechanical analysis, respectively. Copyright © 2011 Society of Chemical Industry     

Foam Mat Drying of Alphonso Mango Pulp

The foam mat drying of Alphonso mango pulp using various food foaming agents, namely soy protein (0.25, 0.5, 1.0, and 1.5%) with methyl cellulose (0.5%), glycerol mono stearate (0.5, 1.0, 2.0 and 3.0%), and egg albumen (2.5, 5.0, 10 and 15%) with methyl cellulose (0.5%), was studied. Drying was carried out in a batch type thin layer dryer at four drying temperatures (60, 65, 70, and 75°C) on 1-, 2-, or 3-mm thickness foamed samples. The optimum concentrations of each foaming agent were determined to be 1% soy protein, 2% glycerol mono stearate, and 10% egg albumen. All were obtained after 25 min whipping time. The drying time was lower for foamed mango pulps as compared to non-foamed pulp at all drying temperatures. Biochemical analysis showed that the foam mat dried powder at 60°C retained a significantly higher (P < 0.05) content of biochemical compounds than at higher temperatures. The treatment of mango pulp with 10% egg albumen and 0.5% methyl cellulose and drying at 60°C (1-mm foam thickness), retained the highest nutritional quality characteristics than the other treatments.     

中国国际丝路中心大厦地下室结构设计

竖向荷载引起的地基总沉降及差异沉降是超高层结构设计中需重点考虑的技术难点。为提高基础刚度,减小差异沉降以及提高底板抗冲切承载能力,除基础能直接支承在基岩上的情况外,国内高度500 m左右的超高层均布置有地下室翼墙。中国国际丝路中心大厦建筑高度498 m,地上101层,地下4层,是否布置翼墙成为地下室设计的重点。针对该项目建筑平面布局,布置翼墙会严重影响地下室使用功能;同时,翼墙本身工程造价大且施工复杂。为此,对比分析了翼墙布置与否的两种模型的自振周期及位移角等指标差异,研究了翼墙开洞与否以及不布置翼墙三种情况下不同桩长方案对底板差异沉降的影响,验算了不布置翼墙情况下底板抗冲切及受弯承载力,并分析了上部结构收缩徐变、底板长期刚度折减对底板影响以及底板变形对核心筒内力影响。结果表明：设置地下室翼墙对结构整体指标影响很小;不布置翼墙,通过调整外框部分桩长,可以使底板差异沉降、底板及核心筒墙承载力均满足要求。为此,该项目未布置地下室翼墙具有可行性,且经济合理。     

浸润剂对玻璃纤维湿法薄毡性能的影响

介绍了浸润剂含量以及不同组分对玻璃纤维水分散性能及玻璃纤维湿法薄毡拉伸强力的影响。结果表明,提高玻璃纤维可燃物含量可提高玻璃纤维水分散性及玻璃纤维湿法薄毡拉伸强力,采用不同类型的偶联剂对玻璃纤维湿法薄毡拉伸强力的影响效果不同。     

Nylon 6 electrospun nanofibers mat as effective sorbent for the removal of estrogens: kinetic and thermodynamic studies

Nylon 6 electrospun nanofibers mat was prepared via electrospinning for the removal of three estrogens, namely, diethylstilbestrol (DES), dienestrol (DS), and hexestrol (HEX) from aqueous solution. Static adsorption as well as the dynamic adsorption was evaluated by means of batch and dynamic disk flow mode, respectively. The kinetic study indicated that the adsorption of the target compounds could be well fitted by the pseudo-second-order equation, suggesting the intra-particle/membrane diffusion process as the rate-limiting step of the adsorption process. The adsorption equilibrium data were all fitted well to the Freundlich isotherm models, with a maximum adsorption capacity values in the range of 97.71 to 208.95 mg/g, which can be compared to or moderately higher than other sorbents published in the literatures. The dynamic disk mode studies indicated that the mean removal yields of three model estrogens were over 95% with a notable smaller amount of adsorbent (4 mg). Thermodynamic study revealed that the adsorption process was exothermic and spontaneous in nature. Desorption results showed that the adsorption capacity can remain up to 80% after seven times usage. It was suggested that Nylon 6 electrospun nanofibers mat has great potential as a novel effective sorbent material for estrogens removal.     

格宾垫工艺在连前排灌站前池中的应用

以江西省新建县廿四联圩连前排灌站为例,探讨了格宾垫工艺在泵站前池中的应用,并阐述了该工艺应用的工程效益.     

Seasonal and diel distributions of denitrifying and bacterial communities in a hypersaline microbial mat (Camargue, France)

Changes in spatio-temporal distribution of bacterial and denitrifying communities were qualitatively studied in a microbial mat from Camargue (France). During a diel and a seasonal cycle, patterns of 16S rRNA and nitrite reductase genes (nirS and nirK) were compared by denaturing gradient gel electrophoresis (DGGE). Statistical analysis of DGGE profiles showed a significant seasonal shift in the community structure of the nirS-containing bacteria with a winter superficial population that extended in summer, whereas the nirK-containing bacteria seemed more affected by vertical gradients rather than by month-to month-changes. Denitrifying activities remained stable during these sampling times. The bacterial community at the surface of the mat also changed according to season, but appeared stable over a day. Finally, during a diel cycle nirK populations were localized in zones with large fluctuations of environmental parameters (oxygen, pH, and sulfur levels) while nirS populations seemed more restricted to the permanent anoxic layer of the microbial mat.     

浸润剂对玻璃纤维湿法毡工艺及性能的影响

考察了浸润剂对玻璃纤维拉丝工艺、玻璃纤维湿法毡工艺及力学性能的影响。研究结果表明：使用浸润剂后玻璃纤维拉丝工艺得到改善;湿法毡力学性能提高,其中使用偶联剂（A-174）处理的湿法毡拉伸强度为213,N/5cm、撕裂强度为2.1,N。经甲酸萃取湿法毡剩余玻璃纤维IR分析可知,使用偶联剂后,玻璃纤维与粘结剂有良好的作用,从微观上解释了湿法毡使用浸润剂后力学性能提高的原因。