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journal of Environmental science and Engineering 2011年第10期5卷 1343-1349页

作者： P. Rzymski B. Poniedziatek j. Karczewski M. Kokocifiski l. Burchardt K. Wiktorowicz Department of Biology and Environmental Protection University of Medical Science Poznafi 61-848 Poland Department of Hydrobiology University of Adam Mickiewicz Poznah 61-614 Poland

Heavy metals currently pose one of the most serious problems in terms of environmental protection. We analysed the effect of cadmium and mercury salts upon chlorophyll fluorescence emision of Microcystis aeruginosa, Cylindrospermopsis raciborskii and Aphanizomenon gracile. Time of incubation (3, 12 and 24 h) and salts concentration(1 μM, 10 μM, 100 μM) influenced the emision. The higher the salt concentration and the longer the time of incubation, the greater the influence on inhibition of chlorophyll fluorescence was observed. Our results might indicate that nontoxic strains of M. aeruginosa MAKR0205 can have a high tolerance to heavy metal ions and ability of their detoxication. Further studies are necessary to confirm their potential ability in the water purification.

关键词：荧光发射流式细胞仪汞盐叶绿素荧光重金属离子蓝藻评价镉

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通过改变管理制度与遗传途径提高母猪生产力

中国畜牧兽医 1985年第2期 36-38页

作者：张晔 j.l.Noguera

母猪的“数字生产力”（numerical pro-ductivity）.数字生产力指每头母猪每年所得的断奶仔猪数。目前这一指标被认为是评价母猪繁殖效率的最佳指标之一。母猪数字生产力可用下式表示:Pn（数字生产力）=(ls（1-Km*）/G+l+IWC)×365式中... 详细信息

母猪的“数字生产力”（numerical pro-ductivity）.数字生产力指每头母猪每年所得的断奶仔猪数。目前这一指标被认为是评价母猪繁殖效率的最佳指标之一。母猪数字生产力可用下式表示:Pn（数字生产力）=(ls（1-Km*）/G+l+IWC)×365式中各符号代表以下五项指标:G——怀胎天数;l——哺乳天数;IWC——断奶—妊娠间隔天数;ls—窝产活仔数;Km——初生—断奶期间的仔猪死亡率。

关键词：母猪生产力窝产仔数多胎性断奶仔猪产仔间隔

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空气质量数据同标准的关系

环境科学研究 1978年第9期 118-122页

作者： l.j.布拉色荷兰全国应用科学研究中心公共卫生工程研究学会

引言空气质量测量本身并不是目的,而只是为某种目的服务的。开始测量前必须首先明确其目的,因为它在很大程度上决定着将要进行的研究的具体内容。地点选择、采样周期与频率以及数据处理都同研究的目的息息相关。阐述设立空气质量监测系... 详细信息

引言空气质量测量本身并不是目的,而只是为某种目的服务的。开始测量前必须首先明确其目的,因为它在很大程度上决定着将要进行的研究的具体内容。地点选择、采样周期与频率以及数据处理都同研究的目的息息相关。阐述设立空气质量监测系统的理由时不可能面面俱到。

关键词：质量数据采样周期污染浓度百分位数频数分布最高浓度峰值浓度质量测量测量周期地点选择

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现代家禽的维生素营养

国外畜牧科技 1991年第1期18卷 35-38页

作者： j.l.McNaughton 周虚

维生素一词源于 Casimir Frank 发现的“辅助食物因子”。后来,Eikman 于1897年证实这种辅助因子是硫胺素(thiamine,VB_1),它能防止鸡的一种脚气病样的疾病一多发性神经炎。Vitamin(维生素)一词由 Vitamine 变化而来,起源于对硫胺素研究。

关键词：家禽维生素营养饲料

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Mutation analysis of autosomal dominant polycystic kidney disease genes in Han Chinese

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第二军医大学学报 2005年第8期26卷 858-858页

作者： Zhang s Mei C Zhang D Dai B Tang B sun T Zhao H Zhou Y li l Wu Y Wang W shen X song j Deparment of Nephrology Changzheng Hospital Second Military Medical University Shanghai 200003China

Diet,dietary selectivity and density of south American grey fox,lycalopex griseus,in Central Chile

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Integrative Zoology 2018年第1期13卷 46-57页

作者： Andrés MUÑOZ-PEDREROs joséYÁÑEZ Heraldo V.NORAMBUENA Alfredo ZÚÑIGA Nucleus of Research in Environmental studies NEA School of Environmental SciencesFaculty of Natural ResourcesCatholic University of TemucoChile Center for Agricultural and Environmental studies CEA ValdiviaChile National Museum of Natural History SantiagoChile Department of Zoology Faculty of Natural and Oceanic SciencesUniversidad de ConcepciónChile

The south American grey fox lycalopex griseus is a canid widely distributed in southern south America;however,some aspects of its biology are still poorly known.We studied the diet and density of l.griseus in the lago Peñuelas Biosphere Reserve,in Central Chile.The trophic niche breadth was B=6.16(B_(sta)=0.47)and prey diversity was H′=2.46(H_(max)′=3.17,j′=0.78).The highest proportions of prey consumed in the diet were Oryctolagus cuniculus(52.21%)and other mammals(32.78%).We compared these results with a latitudinal gradient of diet results for this species in Chile.l.griseus eats mostly mammals(>90%of total prey),consuming the rodent Phyllotis darwini and reptiles in the northern zone;Oryctolagus cuniculus,Octodon degus and Abrocoma bennetti in the central zone;Abrothrix spp.and lagomorphs in the southern zone;and lepus capensis and Ovis aries in the austral zone.The estimated density of l.griseus in lago Peñuelas NR was 1.3 foxes/km^(2).

关键词： density lycalopex griseus Mediterranean-type ecosystem trophic ecology

Thermal, Hardness and Microstructural Characterization of Al-si-siC<sub>p</sub>Composites

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journal of Minerals and Materials Characterization and Engineering 2012年第2期11卷 159-168页

作者： O. A. Alo l. E. Umoru j. A. Ajao K. M. Oluwasegun Center for Energy Research and Development Obafemi Awolowo University Ile-Ife. Nigeria. Department of Materials and Metallurgy University of Birmingham B15 2TT United Kingdom. Department of Materials science and Engineering O.A.U. Ile-Ife. Nigeria.

This study investigated the effects of silicon and silicon carbide particles contents on the thermal, hardness and microstructural behaviour of Al-si-siCp composites. 16 samples of the composite produced by stir casting technique were of silicon contents of 1, 2, 3 and 4% by weigh, and silicon carbide contents of 0.5, 1, 1.5 and 2% by weight for each composition of silicon. Each of the samples were subjected to homogenizing annealing heat treatment. Differential thermal analysis (DTA), hardness test and microstructural analysis were then performed on the samples from each composition. The results obtained showed that the hardness of the composite increased gradually as the silicon and silicon carbide particles content increased. The micrographs obtained revealed the presence of silicon carbide, silicon precipitates and aluminium carbide (Al4C3) within the metallic matrix. The amounts of these phases varied with the silicon and silicon carbide content. All the samples gave DTA curves with major endothermic peaks between 550 – 570℃ and two sets of exothermic peaks between 580 – 610℃ for the first set and between 565 – 570℃ for the second set. It was inferred from the study that although varied silicon and silicon carbide contents affected the thermal, hardness and microstructural behaviour of the Al-si-siCp composites, the variation of the siCp content had a more pronounced effect on the hardness value of the Al-si-siCp composite.

关键词： Al-si-siCp Thermal Hardness Microstructural Characterization

Growth of high quality CdZnTe films by close-spaced sublimation method

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Growth of high quality CdZnTe films by close-spaced sublimat...

苹果无病毒树与潜带病毒及类菌原体树生产性能的比较

第18届国际真空大会

作者： j. Huang * l. j. Wang K. Tang j. j. Zhang W. M. shi Y. B. Xia l. X. Gang school of Materials science and Engineering shanghai University shanghai 200072 China

In the last decade, CdZnTe （CZT） has attracted considerable interest because of its wide applications in optoelectronic devices. It is one of the most promising materials for X-ray and gamma-ray detectors. Recently, advancements in two-junction solar cell technology have also indicated that CZT may be successfully used in the fabrication of thin film tandem solar cells. The main requirement for these devices includes a large active area, high sensitivity, wide dynamic range, and low production cost, etc. However, single-crystal CZT is not suitable for a large-area fabrication due to the difficulty in manufacturing defect-free, uniform bandgap and highly resistive large area wafers. For production of large area CZT material with lower cost, thin film technology can be used. Previous reports on polycrystalline CZT films have shown replacement of CdZnTe single crystal

关键词： CdZnTe Closed space sublimation film

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国外农学（果树） 1989年第2期 45-47,34页

作者： Penrose l.j. 洪霓

本文对3个苹果品种(红玉、红冠、澳洲青苹)的无病毒树与潜带病毒及类菌原体树的生产性能进行了比较。3年的试验结果表明,红玉、红冠和澳洲青苹无病毒树的产量比带毒树分别增加56%、40%和41%。3个品种的单株生产效率(单位干周面积的产量... 详细信息

本文对3个苹果品种(红玉、红冠、澳洲青苹)的无病毒树与潜带病毒及类菌原体树的生产性能进行了比较。3年的试验结果表明,红玉、红冠和澳洲青苹无病毒树的产量比带毒树分别增加56%、40%和41%。3个品种的单株生产效率(单位干周面积的产量)或果实可溶性固形物含量及红玉、红冠的着色面积和着色程度,在病树与健康树之间均无显著的差异。红玉无病毒树冠较潜带病毒树宽22%,红冠无病毒树比带毒树高11%,澳洲青苹无病毒树较带毒树高9%,宽15%。

关键词：苹果无病毒潜带病毒生产性能

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MAN公司游艇和工作船用新型6缸发动机

汽车与新动力 2017年第1期49卷 26-28页

作者： B.Huneke j.Kleesattel s.lser M.Zundel 李媛媛

MAN公司在量产的D26商用车发动机的基础上开发了1款单位功率质量较小且省油的紧凑型船用发动机——新款D2676发动机。该发动机不仅符合当前的排放标准,也为满足未来排放法规做好了准备。MAN公司有针对性地采用车用发动机标准件和非标准... 详细信息

MAN公司在量产的D26商用车发动机的基础上开发了1款单位功率质量较小且省油的紧凑型船用发动机——新款D2676发动机。该发动机不仅符合当前的排放标准,也为满足未来排放法规做好了准备。MAN公司有针对性地采用车用发动机标准件和非标准件,以可接受的成本开发了经全面验证的船用发动机。

关键词：船用发动机燃烧排放冷却系统