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发酵产氢的影响因素Ⅱ.反应器类型、营养条件和环境条件 总被引：1，自引：0，他引：1
发酵产氢技术在国内外受到了普遍关注,然该过程是一个极其复杂的生物过程,受诸多因素的干扰.如何优化产氢过程,确保稳定、持续和高效的产氢能力已成为发酵产氢研究的重点课题.本文在查阅了国内外大量文献的基础上,总结了主要影响因子(包括接种物、基质、反应器类型、营养条件和环境条件)对发酵产氢的影响,对发酵产氢朱朱的研发工作提出了... 相似文献
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本文是在长期生产青霉素的过程中,累计了大量的生产数据的基础上,主要对青霉素发酵过程中的各种影响因素,进行了数据建模分析。通过对生产数据进行数据分析,并结合实际生产经验,建立了能够模拟青霉素发酵过程变化的数学模型。应用这些模型,可以在一定程度上对青霉素发酵过程进行优化;判定发酵产量提高的潜在的可能性,从而使发酵生产不断趋向最优状态,提高生产的经济效益。 相似文献
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阐述了酒精生产过程中几种对酵母产生应激反应的因子:乙醇、温度、有机酸和pH等,利用这些信息,我们可以在实际酒精生产中对发酵过程进行有效的控制。 相似文献
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柳盼盼 《内蒙古科技与经济》2020,(7)
采用主成分分析法,对甘肃省2008年～2017年13个水资源承载力影响因子进行分析。从13个因子中共提取了3个主要成分,根据因子载荷矩阵得出每一个主成分得分,进而求得甘肃省每一年的综合评分。最终结果表明:甘肃省水资源承载力逐年下降,水资源再开发利用的潜力愈来愈小,影响水资源承载力的主要因子是城镇发展、农业发展以及废水处理技术等。 相似文献
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大豆是一种重要的农产品资源,压榨行业是大豆产业链上的重要环节,它的原料来自大豆种植业,生产的豆粕主要用作饲料业和畜牧业的蛋白原料。自1996年以来,中国大豆进口量不断增加,是全球最大的大豆压榨国,大豆压榨企业布局发生了重大变化。美国和巴西是世界上最大的大豆生产国,也是主要的大豆压榨国,对比分析美国、巴西及中国大豆压榨企业布局特征,对指导中国未来大豆压榨企业投资布局具有重要意义。本文根据项目组20多年持续收集的相关资料,以及美国农业部、巴西植物油加工协会的资料,对比美国、巴西和中国的大豆供求基本特点、大豆生产布局、畜牧业和饲料业分布、大豆压榨企业和产能布局特点发现,美国、巴西的大豆压榨企业主要集中在大豆主产区,并与其国内豆粕市场空间高度重合,呈现“大集聚、小分散”的布局形态;而中国大豆压榨企业布局和大豆制品销区在空间上不完全重合,逐渐形成了以沿海港口城市为压榨核心,以长江、哈大铁路等交通运输线路扩散的带状布局形态。区域畜牧业、饲料业发展决定着豆粕市场需求空间,但是大豆原料供给与豆粕需求在空间上往往存在差异,除了不同国家和区域的产业政策外,大豆原料及豆粕的运费成本、豆粕的市场潜力、区域内大豆压榨产能规模及企业间分工协作所产生的集聚效应是造成大豆压榨企业空间布局形态存在巨大差异的主要原因。 相似文献
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Amin L Ahmad J Jahi JM Nor AR Osman M Mahadi NM 《Public understanding of science (Bristol, England)》2011,20(5):674-689
Despite considerable research in advanced countries on public perceptions of and attitudes to modern biotechnology, limited effort has been geared towards developing a structural model of public attitudes to modern biotechnology. The purpose of this paper is to identify the relevant factors influencing public attitudes towards genetically modified (GM) soybean, and to analyze the relationship between all the attitudinal factors. A survey was carried out on 1,017 respondents from various stakeholder groups in the Klang Valley region. Results of the survey have confirmed that attitudes towards complex issues such as biotechnology should be seen as a multifaceted process. The most important factors predicting support for GM soybean are the specific application-linked perceptions about the benefits, acceptance of risk and moral concern while risk and familiarity are significant predictors of benefit and risk acceptance. Attitudes towards GM soybean are also predicted by several general classes of attitude. 相似文献
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BackgroundWe aimed to test the possibility of improving polypeptide production from soybean meal fermentation by engineered Aspergillus oryzae strains. Four different protease genes were cloned and transformed into wild-type A. oryzae, and the engineered A. oryzae strains were then used for soybean meal fermentation.ResultsThe results showed different degrees of improvement in the protease activity of the four transformants when compared with wild-type A. oryzae. A major improvement in the polypeptide yield was achieved when these strains were used in soybean meal fermentation. The polypeptide conversion rate of one of the four transformants, A. oryzae pep, reached 35.9%, which was approximately twofold higher than that exhibited by wild-type A. oryzae. Amino acid content analysis showed that the essential amino acid content and amino acid composition of the fermentation product significantly improved when engineered A. oryzae strains were used for soybean meal fermentation.ConclusionsThese findings suggest that cloning of microbial protease genes with good physicochemical properties and expressing them in an ideal host such as A. oryzae is a novel strategy to enhance the value of soybean meal. 相似文献
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The relationship between protease and Desferal production was assayed. Experiments were performed using a cultivation of Streptomyces pilosus ATCC 19797 in soybean broth medium containing 2% soybean flour and 2% mannitol. The metabolism of the trihydroxamic acid sidrophore desferrioxamine B and protease production by a S. pilosus in nine continues days after culture were investigated as well as the effect of protease inhibitors was examined. It is found that the Desferal formation decreased with increased protease production. Also the effect of protease inhibitors and minerals in determined day of protease production in the culture medium by S. pilosus has been investigated. 相似文献
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刺五加提取物对断奶仔猪氨基酸消化吸收的影响 总被引：1，自引：0，他引：1
试验选用体重相近的21日龄断奶的三元杂交仔猪60头，按完全区组设计分为3个处理，处理1饲喂添加0.10%刺五加提取物日粮，处理2饲喂添加0.02％硫酸粘杆菌素日粮，处理3饲喂基础日粮. 分别于添加后第7、14和28 d每个处理随机取5头试猪，前腔静脉采血，测定血清游离氨基酸含量；采血后的试猪经麻醉处死，取回肠末端食糜测定其中的氨基酸含量. 结果表明，随着饲喂时间的延长，刺五加提取物显著提高仔猪血清中游离氨基酸的含量，降低回肠食糜中氨基酸的含量. 提示刺五加提取物可促进断奶仔猪对蛋白质的消化，增加小肠对氨基酸的吸收，有助于仔猪的生长. 相似文献
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本研究以氮肥,磷肥,补水量为试验因子,以大豆WUE为指标,利用MINITAB15统计分析软件进行试验设计和数据分析,通过响应曲面法建立水肥相互作用对大豆WUE的影响的二次多项数学模型,拟舍检验极显著,模型拟合的好。同时分析了氮肥,磷肥,补水量单因素对大豆WUE的影响,明确了不同水肥水平条件下大豆WUE高低的变化规律,为挖掘大豆WUE提供了理论依据。 相似文献
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P. V. L. N. Srinivasa Rao K. V. Dakshinamurty K. S. S. Saibaba P. V. L. N. Murty G. Venkataramana V. Sreekrishna 《Indian journal of clinical biochemistry : IJCB》1999,14(2):184-188
Chronic renal failure, characterised by two factors acting in opposite directions with respect to the serum thyroid homone
levels was chosen for the study. Healthy controls, donors undergoing nephrectomy and renal transplant recipients were studied.
In transplant recipients, presurgical levels of total thyroxine(TT4), free triiodothyronine(FT3) and free thyroxine(FT4) were
lower than controls, and immediately after the release of arterial clamps, there was an upsurge of total triiodothyronine
(TT3), TT4, FT3 and FT4 due to administered and/or endogeneously secreted catecholamines. The levels of the 7th day were comparable
to the presurgical levels. The changes observed in donors and recipients were similar indicating that the hormonal changes
observed are mostly due to surgical stress. Recovery in the hormonal status did not start in the first week of posttransplant
period. 相似文献
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“大豆优异基因资源发掘及其基因组研究” 立项背景和意义 总被引：3，自引：0，他引：3
大豆是重要的粮食和油料作物,在我国国民经济发展中具有重要地位
。在中国加入WTO的形势下,我国大豆面临着生产落后、供给严重不足、国内大豆产业受到
进口转基因大豆的严重冲击的局面。我国是大豆的起源中心,收集保存的大豆资源蕴藏着丰\\r
富的有益基因。开展大豆优异基因资源发掘、大豆基因组序列测定与生物信息学分析、大豆
优异基因的分子标记、定位与克隆等关键科学问题研究,将推动大豆的分子生物学研究并提\\r
高大豆的分子育种水平,为大豆遗传改良奠定坚实的理论基础。针对这些内容,2003年国家
自然科学基金委员会设立了重大项目“大豆优异基因资源发掘及其基因组研究”。 相似文献