Electronic nose analysis of volatile compounds from poultry meat samples,fresh and after refrigerated storage

Electronic nose technology has previously been applied to the assessment of the quality of red meats, pork and fish, but not poultry products. In the present study the ability of the electronic nose to assess the microbiological quality of raw poultry meat as a function of storage time and temperature was investigated. Four types of chicken pieces (boneless breast with and without skin, wings and thighs) were stored for up to 2 days at 13 °C (the maximum allowable temperature in poultry processing environments) or for up to 5 days at 4 °C (refrigeration temperature for raw poultry products prior to shipping or further processing). Saline rinses of meat samples were serially diluted in tryptic soy broth to 10^?10. The rinses and their associated serial dilutions were analysed on an electronic nose with 12 metal oxide sensors in order to determine the specificity and sensitivity respectively of the assay. Principal component analysis (PCA) maps of the data confirmed that the electronic nose could differentiate volatile compounds associated with individual types of meat samples properly stored at 4 °C from those maintained at processing temperature, 13 °C, for a comparable time, even as early as day 1 of storage. Differences in headspace gases from any type of meat sample stored at one temperature could also be determined with increased storage time. However, data from samples stored at 4 °C clustered more tightly in PCA maps than those associated with samples maintained at 13 °C, indicating a greater diversity in volatile compounds at the higher temperature. We have shown herein that the electronic nose can detect changes in the volatile compounds associated with chicken meat based on product storage time and temperature; the technology can assess length of sample storage as well as deviation from refrigeration temperature. Published in 2002 for SCI by John Wiley & Sons, Ltd.     

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??Based on the practices of explorating and developing the big gas field in the central part of Shanganning Basin and the comprehensive study outcome in recent years, the gas field characteristics and its resource scale are expounded. It is verified that the gas field is the largest ready one on the land of China at present. Furthermore, it is analysed that replacing oil with gas to gas Beijing is the optimum plan of giving play to society-economy benefit of the natural gas resource in North Shanxi. Finally, the suggestion of rapidly achieving the above plan is proposed out.     

The Cognitive Origins of Social Stratification

In evolutionary psychology, cultural phenomena are explained with reference to evolved psychological processes. This paper presents an economic approach to explore this link by demonstrating how social stratification can arise in game-playing populations as a result of social categorisation of and inference from arbitrary agent traits. The computer simulation of the model demonstrates that agents' increasing ability to categorise opponents in the chicken game generates an increasing number of social groups whose members share commonality of fate both in terms of opponent behaviour and payoff levels. JEL classification: C72, D83, J70     

Partitioning of chicken egg white proteins in polyelectrolyte/salt aqueous two‐phase systems composed of polyethyleneoxide–maleic acid copolymer and potassium phosphate

Aqueous two‐phase systems were formed from solutions of a polyelectrolyte, polyethyleneoxide–maleic acid copolymer, and potassium phosphate. The properties of such aqueous two‐phase systems were highly dependent on pH. This was reflected in the partition behavior of three chicken egg white proteins: lysozyme, conalbumin and ovalbumin. Separability of these three proteins was improved by the use of the polyelectrolyte, in comparison with when uncharged polyethylene glycol (poly(1,2‐dihydroxyethane)) was used as a phase‐forming polymer. © 2002 Society of Chemical Industry     

续写北京中轴壮丽之美--北京南中轴绿地景观设计思路

北京传统中轴线是北京古都格局中的灵魂,这一轴线上分布着一系列重要的标志性建筑,形成壮丽恢弘的气势,被古人尊称为"龙脉"、"天街",在世界上享有盛誉.就这一轴线南段总体环境设计理念进行了阐述与分析.     

Emulsion Stability and Water Uptake Ability of Chicken Breast Muscle Proteins as Affected by Microbial Transglutaminase

ABSTRACT: Using response surface methodology, the effect of microbial transglutaminase (TG) concentration and incubation time (IT) after emulsification, but before creaming, on the functional properties of chicken meat proteins was examined. TG improved the stability of emulsions (ES) made with a high-salt chicken meat protein extract, although TG did not significantly affect the amount of protein incorporated into the emulsion cream layer. IT significantly enhanced ES when incubated at 40 °C, but not at 4 °C. TG increased the water uptake ability (WUA) of both chicken muscle and chicken muscle protein extract incubated at 40 °C and 4 °C. Similarly, TG increased the protein and water content of the pellet formed in the WUA test. TG therefore appears to be a useful method to enhance the stability and yield of meat batters.     

北京引拒工程对下游地区影响

采用1956～1997年径流量资料系列,对拒马河流域的地表水资源作了评价,并在此基础上对北京引拒工程的可引水量进行了计算。依据拒马河流域水资源及开发利用现状和供需水预测,论证了北京引拒工程实施,将造成下游地区水资源供需矛盾加剧、白洋淀于淀几率增加及水质恶化等一系列严重问题。现就北京引拒工程对下游地区影响问题作了较为全面的分析。     

北京市灌溉工程经济效益分析

根据降水条件和作物品种所得出的不同水文年的灌溉工程经济效益分摊系数 ,推算出北京市194 9年以来的灌溉工程经济效益为 310 .0 3亿元 ;指出节水灌溉在农业可持续发展中的重要作用 ;针对北京市水资源紧缺的现状 ,提出了农业可持续发展的对策。     

SPF鸡肠源嗜酸乳杆菌的分离及生物学特性研究

无菌采集SPF鸡盲肠粘膜层内容物．接种MRS培养基和SL乳杆菌选择培养基，厌氧培养分离乳杆菌。对分离菌从形态学、生化特性及耐氧性、产酸性、耐酸性、药物敏感性、抑菌性、粘附性、致病性等生物学特性研究。实验结果对照《伯杰氏细菌学鉴定手册》(第9版)的参数综合评判。结果表明从SPF鸡盲肠内分离到2株嗜酸乳杆菌，从中筛选出一株适宜研制家禽微生态制剂的菌种。     

低技术生态建筑的形态设计分析

随着时代的发展,建筑的生态环境品质开始日益受到人们的关注。生态建筑成为利用不同地区自然生态环境,为人类提供更好的居住条件的新型建筑类型。其中,低技术生态建筑是一个重要的研究类型。本文即对低技术生态建筑的形态设计相关问题进行了分析。将结低技术生态建筑分为景多种不同的形态模式,并对对低技术生态建筑的未来发展予以合理的展望。