加强供电企业的线损管理措施

电力网电能损耗是供电企业一项重要的技术经济指标,降低线损率是所有供电企业所面对的主要工作和长期任务。本文介绍了线损的分类及影响线损管理的因素,探讨了供电企业线损管理存在的问题,提出供电企业线损管理措施。     

供电企业计量自动化系统运用中线损计算的差异分析

线损是供电企业一项重要的技术经济指标,降低线损率是供电企业所面对的主要工作和长期任务之一。文章针对计量自动化系统运用中线损计算的差异分析,归纳总结出一套适用于供电企业强化线损管理,降低电能损耗管理标准,从而提高线损管理品质。     

降低低压电网线损管理措施探讨

电能在输变电设备和线路中传输,会产生损耗,简称线损。其线损值与电网输入量的百分比为线损率。线损率反映了电网输送和分配电能的效益,是衡量电网经济技术性能的一个重要参数,也是衡量供电部门经济效益的一个重要指标。本文主要从电力供应管理实践角度出发,探讨分析了低压线损管理的重要性、低压线损产生的原因,以及从技术方面和管理方面旨在降低低压损耗,提高电力效率的措施。     

浅谈配电网节能降损的主要技术措施

降低电能损耗,既是供电企业提高经济效益的要,也是当今节能型社会的必然求。文章从配电网线损组成和产生原因入手对配电网线损作了阐述,提出了配电网节能降损的些主要技术措施。     

关于电网线损分析及降损措施的探究

电网损耗是目前电力输送过程中不可避免的能量损耗,也是电力企业经济效益的影响因素。对电网损耗的控制是电力企业管理水平和技术实力的综合体现。文章从电力企业工作实际出发,围绕电网线损问题进行探讨,首先阐述了电网线损的基本概念,分析了形成电网线损的主要原因,进而对降低电网线损提出具体解决办法。     

浅谈县级供电企业理论线损计算与典型线损分析

电能在传输的过程中经过供电线路和配电变压器等相关设备时,会产生电能损耗和功率损耗,便称为供电损耗,简称为线损。线损主要可以分为两大部分,一是可变损耗,主要指电流通过导体所产生的能量损耗;二是固定损耗,主要是变压器的铁损、现场运行的电能表内部线圈的损耗,电力电容器的内部介质损耗等,上述两部分的线损通常称为技术损耗,除此以外的其他损耗则称为管理损耗,主要是指因为供电企业管理不够完善、要求执行不严格、现场运行的计量装置存在误差无及时校验修正等因素造成的各种电能损耗。     

配网线损原因分析及其降损措施

配网供电过程中会存在不可避免的损耗，但由于技术不科学和管理不当的原因会造成线损增大，从而会造成不必要的经济损失，同时还会影响配电线路的供电质量水平。文章主要就配电线路损耗的原因展开分析，并提出相应的降低损耗的措施，从而提高配网供电的经济效益和供电质量。     

浅谈电能损耗及县级供电企业线损管理

电能损耗是电网运行过程中普遍存在的问题,电能损耗无法彻底杜绝,只能在电网运行过程中尽量降低。对于县级供电企业而言,要通过严格加强线损管理,逐步降低电能损耗,从而确保电力企业经济效益。文章对电能损耗及县级供电企业线损管理进行简单探讨。     

在线监控系统在反窃电及降低线损方面的运用

线损是电能在电网传输过程中,在输电、变电、配电和营销等各个环节所产生的电能损耗和损失,包括技术线损和管理线损。随着当前电网规划技术水平、电力设备制造工艺的提高及新型节能型设备的推广使用,技术降损空间已大幅降低。降低线损更大程度上取决于不明线损(包括窃电和计量异常丢失电量)。文章从目前常见的三种窃电方法出发,结合线损、计量自动化系统、营配信息集成等,并以此为基础,介绍在线监控系统的原理、监控方法及效果,供同行参考。     

试析如何降低县级供电企业电网线损

随着经济的飞速发展,县级供电企业的供电量也急剧增加。电网线损指标已成为关系供电企业经济效益的一个主要因素。县级供电企业具有基础薄弱、管理难度大、涉及面广、综合性强,新旧体制交替等大电网所不具有的制约因素,从而决定了县级供电企业的电网线损管理需要有一套与之适合的管理模式。如何切实有效地做好县级供电企业的线损管理,如何更有效的降低电网损耗是当前摆在我们每一个电力工作者面前的重要课题,以下笔者从技术措施和管理措施两方面分别分析了如何更加有效的降低县级供电企业电网线损。     

Effects of housing system and age of laying hens on egg performance in fresh pasta production: pasta cooking behaviour

BACKGROUND: Very few studies concern the effects of layer housing systems and age on egg technological properties. Thus the aim of this work was to study the influence of these two factors on egg performance in fresh pasta production, focusing on pasta cooking behaviour. Samples of pasta subjected to analysis were prepared with eggs laid by Hy‐Line Brown hens (from 27 to 68 weeks old) housed in cage, barn and organic systems. RESULTS: Higher average values of weight increase and matter loss during pasta cooking were observed for samples prepared with eggs laid by older hens. Such cooking behaviour indicated the development of a weaker pasta protein network, resulting from a decrease in the quantity of albumen protein and an increase in fat content, which is due to the reduction in albumen/yolk ratio during hen aging. The housing system had a significant effect only on matter loss in cooking water, but differences between samples were so small as to be unlikely perceived by consumers. CONCLUSION: Both hen age and housing system significantly affected pasta cooking behaviour, but the greatest effect was exerted by the hen age. Copyright © 2010 Society of Chemical Industry     

膨化食品生产工艺与设备

本文介绍了直接膨化食品生产线。包括生产线工艺流程、生产工艺要点,以及生产线所用机械设备等。     

直接染料在牛仔布经纱轧染中的应用

本文介绍直接染料在牛仔布经纱轧染中的应用情况，包括染料、助剂的选用，工艺流程及工艺条件的确定，以及轧染的注意事项。     

Comparison between rabbit lines for sensory meat quality

Rabbits from three synthetic lines were used in the experiment. Line R was selected for growth for 24 generations. Lines V and A were selected for litter size at weaning for 30 and 33 generations, respectively. Sensory analysis was carried out on the Longissimus muscle. The parameters evaluated were: juiciness (J), hardness (H), fibrousness (F), flouriness (Fl), intensity of rabbit flavour (IRF), aniseed odour (AO), aniseed flavour (AF), liver odour (LO) and liver flavour (LF). A Bayesian analysis was performed. Line V was only 82% as juicy as line R. Line V was 18% harder and 17% more fibrous than line R. Lines A and R had the same H and F. No differences in Fl were found. Small effects were found for flavour traits. We conclude that line origin has an influence on some sensory traits determining rabbit meat tenderness.     

Comparison of texture and biochemical characteristics of three rabbit lines selected for litter size or growth rate

Meat texture and some biochemical characteristics that could influence meat tenderness were studied in rabbit loins. Rabbits from three synthetic lines were compared, lines V and A selected for litter size at weaning and line R selected for growth rate between weaning and slaughter time. The activities of cathepsins, collagen content and textural properties measured by Warner-Bratzler (WB) shear device and by the texture profile analyses (TPA) test were measured. Line R was more tender than line V and line A had an intermediate tenderness, Rabbit meat from line R had higher activity of cathepsins B and B + L, lower total collagen content and lower cohesiveness, springiness and chewiness, shear force and total work (area under the curve obtained with WB device) than line V. Line A had an intermediate texture between lines R and V. Our results show evidence of genetic variation between lines in rabbit meat tenderness.     

Comparison of carcass and meat characteristics of three rabbit lines selected for litter size or growth rate

Rabbits from three synthetic lines were compared. Line V and A were selected for litter size at weaning and line R was selected for growth rate between weaning and slaughter time. Forty animals of each line were slaughtered at 9 week of age. Comparisons between lines were made using Bayesian statistical techniques. Line R had a higher meat/bone ratio, higher loin percentage and higher ultimate pH of M. Longissimus lumborum (LL) than A and V, but lower dressing out and lower hind part percentages. Some differences between lines in carcass and meat colour were found. No differences were found for percentage of released water of LL and for the activity of energy metabolic enzymes. At present, rabbit carcasses are not costed according to their retail cuts or meat/bone ratio, but dressing out percentage is taken into account, thus breeding companies should be concerned about lower carcass yield of lines selected by growth rate.     

纤维素酶整理苎麻织物的减量及强力变化

文章通过调查盛夏纤维素酶处理苎麻织物减量与强力损失的变化,优化酶处理工艺条件。通过单因子实验发现,减量率和强力损失率随着酶浓度的增加、处理时间的延长而提高;随着pH值的提高而降低;减量率在温度50℃时最高,断裂强力损失率随温度的升高而降低。实验结果表明盛夏纤维素酶处理后苎麻织物强力损失率的变化明显,而减量率的变化较小,强力损失率与减量率之间存在一定的相关性。     

The relationship between pig genetics, myosin heavy chain I, biochemical traits and quality of M. longissimus thoracis

The relationship between muscle biochemical traits, myosin heavy chain I and meat quality of longissimus thoracis was studied using gilts from five divergent porcine lines (A to E) (carcass weight: 83.7±8.7 kg). Intramuscular fat (IMF) and haem pigments content as well as myosin heavy chain 1 (MyHC I) percentage and the activity of lactate dehydrogenase (LDH) and isocitrate dehydrogenase (ICDH) were determined. Only group E, a well conformed line of pigs, included the halothane positive genotype. The presence of the Hal gene in this line resulted in meat of poorer quality in terms of meat of higher exudate compared to line D, also a well conformed line of predominantly Pietrain origin but being halothane gene free. Line C presented the highest IMF content (2.02%) as well as high oxidative characteristics (MyHC I, 10.0%; LDH/ICDH, 1.92 μmol nmol(-1); ICDH activity, 1.78 nmol min(-1) g(-1)) and the lowest drip losses (5.3%). According to a principal component analysis including MyHC I, biochemical traits and meat quality parameters, line C was characterized by a high IMF content and oxidative traits, and line B by a high glycolytic metabolism. Line E was distinguished by high drip losses and by low pH(45) and pH(u). In conclusion, several observed differences in muscle metabolism between lines free of the halothane gene (A, B, C and D) must be caused by other "genetic background" factors.     

禁食对僵直前后鸡肉加工特性的影响

三黄鸡分别禁食0、8、16h和24h,采用三管齐断法宰杀,于宰后僵直前(0h)、僵直阶段(3h)和僵直后(24h)分别制成鸡肉糜,测定新鲜肌肉的pH值,鸡肉肠的蒸煮损失、加压损失、剪切力值、肉色和质构等指标,观察不同禁食时间对僵直前后鸡肉糜制品品质的影响。结果表明：随着禁食时间延长,pH值先升高后降低(P＜0.05),蒸煮损失和加压损失都有增加的趋势,剪切力值有降低的趋势,未禁食组僵直前鸡肉肠的硬度、弹性、黏聚性、胶黏性和咀嚼性最高,禁食16h组僵直和僵直前的质构特性优于禁食8h和24h组。随着宰后时间延长,pH值显著降低,持水力显著下降,僵直后鸡肉肠的质构特性劣于僵直和僵直前鸡肉肠的质构特性。     

苇浆OHMP漂白生产线的运行

介绍苇浆OHMP清洁漂白的工艺流程、工艺条件和生产中应注意的问题。