Performance evaluation of integrated trigeneration and CO2 refrigeration systems

Food retailing is one of the most energy intensive sectors of the food cold chain. Its environmental impacts are significant not only because of the indirect effect from CO₂ emissions at the power stations but also due to the direct effect arising from refrigerant leakage to the atmosphere. The overall energy efficiency of supermarkets can be increased by integrating the operation of CO₂ refrigeration and trigeneration systems. This paper compares three alternative schemes in a medium size supermarket. Experimental results and simulation studies have shown that the best scheme for energy and GHG emissions savings is the one where the cooling produced by the trigeneration system is used to condense the CO₂ fluid in the refrigeration system to ensure subcritical operation throughout the year. It is shown that this system can produce 30% energy savings and over 40% greenhouse gas emissions savings over conventional refrigeration and indoor environment control systems in supermarkets.     

Activation of the sodium/hydrogen exchanger via the fibronectin-integrin pathway results in hematopoietic stimulation

A comparison of two assessment methods, consensus among experts and research synthesis of the scientific literature, was performed using a surgical procedure, carotid endarterectomy (CE), as an example. These two methods have been widely advocated as being scientifically valid. While the comparison revealed a number of areas of general agreement, important differences between the two methods emerged. For example, 30-day mortality for asymptomatic patients was considered an effective outcome (ranked first) by the synthesis, but only "equivocal" (ranked third) of six major indicators reported by the consensus method. The synthesis results are also consistent with other literature reviews as well as with recent large-scale randomized trial results. A number of factors that could account for differences between the two methods were examined. Overall, use of consensus panels may be appropriate early in the development of an intervention where the evidence is sparse, while quantitative research synthesis is preferable when a number of high-quality studies have been performed.     

长江流域水生态文明城市试点建设浅析

水生态文明是生态文明的重要组成和基础保障,基于长江流域第1批水生态文明城市建设试点技术评估,对长江流域水生态文明城市建设成效进行分析;通过资料复核、现场查勘等方法对任务与指标完成情况、建设成效及保障措施落实情况、宣传推广情况进行分析,总结了不同发展水平、不同水资源条件、不同水生态状况下的5条建设模式与7条建设经验。研究成果为进一步完善推行河湖长制、生态红线划定和生态空间管控、水生态补偿等方面的制度体系提供支撑;为进一步提升长江流域水生态文明建设的指导水平和管理能力提供参考。     

基于BIM的最后计划者体系研究

通过分析BIM和最后计划者体系的主要功能,利用交互矩阵对两者的交互性进行协同效益分析。最后将BIM的4D施工模拟、动态信息管理及数据资源集成等关键技术融入到最后计划者体系中,创立了基于BIM的最后计划者体系。     

光纤化学pH 传感技术的现状和进展

本文综述了光纤化学 pH传感器的现状和发展 .分别从 pH指示剂的试剂固定化方法和传感信号的产生与检测方式来阐述近年来光纤化学pH传感器新技术的发展 ;同时也介绍了其他 pH传感器的发展现状 .     

单晶硅的光谱响应测试技术研究

为实现对硅光电池光谱响应的快速、准确在线测试,开发一种硅光电池光谱响应测试软件系统.该系统采用三光栅单色仪、光源、样品室、精密锁相放大器、斩波器等作为硬件设备.该系统以VC++6.0为开发平台,具有高精度、高准确度,对外界干扰小等优点.并对硅光电池的光谱响应进行详细地分析、计算,表明与实测结果吻合.单晶硅的光谱响应的起...     

PHYSICOCHEMICAL, TEXTURAL AND NOODLE-MAKING PROPERTIES OF WHEAT DOUGH CONTAINING ALGINATE

The effects of the addition of alginate on the physicochemical, rheological and noodle-making properties of wheat flour were studied. The hydration properties (water absorption index, water solubility and swelling power) of wheat flour increased with increasing levels of alginate due to its high affinity to water. The addition of alginate caused increased water absorption and dough development time in the farinogram while the tolerance of dough to mixing was reduced. Also, the syneresis of the wheat flour gel was significantly reduced during freeze-thaw treatments when prepared with alginate. With the addition of alginate, the noodles exhibited an increase in the cooked weight and a decrease in the cooking loss. Moreover, the addition of alginate led to significant increases in the cutting and tensile forces of the noodles. In addition, the noodles containing more alginate exhibited lower lightness and redness, while yellowness was increased.

PRACTICAL APPLICATIONS

The purposes of this study are to examine the effects of alginate on the physicochemical and rheological properties of wheat flour dough and to evaluate its performance in noodle-making.
This study demonstrates that alginate can be used as a food additive to control and modify the rheology and texture of wheat flour products.     

The isolation and characteristics of the green monkey lentivirus

We characterized the simian immunodeficiency virus isolated from Cercopithecus aethiops (subspecies C. a. pygerythrus) originating from Kenya. SIV was isolated and continuously produced with the MOLT4 clone 8 cell line and was designated as SIV-SU1. SIV-SU1 isolate replicated with high efficiency in MOLT4 clone 8, MT-2 with moderate efficiency in CEM x 174 and with poor efficiency in HUT-78, U937, C8166. The infection of MT-2, C8166 and HUT-78 resulted in extensive cell killing. Western blotting of purified preparations of SIV-SU1 revealed viral proteins of 130, 68, 55, 41, 24, 17 kDa. Cross-reactivity of SIV-SU1 proteins with HIV-1, HIV-2, SIVmac, SIVsm, SIVmnd was studied by radioimmunoprecipitation assay. The most extensive cross-reactivity was observed with SIVmac. Total cellular DNA from chronically infected cells was hybridized to SIVagm266 DNA probes. Detection of cross-hybridizing DNA sequences required very low stringency, and the restriction endonuclease fragmentation pattern of SIV-SU1 differed from other SIVs.     

Effect of chronic duodenal ulceration and its treatment with lanzoprazole or sucralfate on gastroduodenal mucosal protein turnover and TGF-alpha, bFGF, and EGF receptor expression in humans

In order to investigate whether chronic duodenal ulcer disease is a consequence of disturbed mucosal turnover and growth factor expression, we studied 16 patients with duodenal ulcers before, during, and after endoscopic healing with lansoprazole or sucralfate. Before treatment, gastric fundal and antral mucosal protein turnover rates were higher in patients than controls, without parallel increases in growth factors. Both forms of therapy produced similar changes, with overall increases in duodenal mucosal turnover and transforming growth factor-alpha (TGF-alpha) and epidermal growth factor receptor (EGF-r) levels. Measurements after healing showed persistent elevations of mucosal turnover in the antrum and duodenum and depressions of basic fibroblast growth factor (bFGF) in gastric fundal and duodenal mucosa. We conclude that mucosal turnover is abnormally high in patients with chronic duodenal ulcer disease and is not easily explained by growth factor changes. The failure of lansoprazole and sucralfate to normalize rates, despite endoscopic healing, may explain the high ulcer relapse rates in non-HP-eradicated patients.     

Wet chemical synthesis of low bulk density aluminium hydroxide powder

Fine, low bulk density aluminium hydroxide powdered gel was prepared by the mild base hydrolysis of an aqueous solution of aluminium sulfate with hydrazine hydrate. Parameters such as method of addition of reactant, initial concentration of Al³⁺, mole ratio, final pH and hydrolysis temperature have a profound effect on the lightness and particle size of the powder. Optimized conditions showed that the final pH, Al³⁺ concentration and method of addition of reactant have a major contribution on the formation of lighter grade powder. Experiments conducted using other bases also produced lighter particles under similar conditions. Deviation from the optimized conditions led to formation of a higher bulk density product. Copyright © 2003 Society of Chemical Industry