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Reproductive behavior in horseshoe crabs:Does density matter?

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Current Zoology 2010年第5期56卷 634-642页

作者： Jennifer h.MATTEI Mark A.BEEKEY Adam RUDMAn Alyssa WOROnIK Department of Biology Sacred Heart University Department of Biology Southern Connecticut State University

While the four species of horseshoe crabs share many common reproductive traits with respect to their reproductive systems, they do differ with respect to their mating behavior （monogamy vs. polygynandry）. Past research has attributed these differences to a number of factors including： spawning densities, operational sex ratios （OSR＇s）, male condition （or age）, environmental and/or genetic factors, or a combination thereof. Mating behaviors in the three Asian horseshoe crab species （Tachy-pleus gigas, T. tridentatus, and Carcinoscorpius rotundicauda） with low spawning densities and 1：1 operational sex ratios are typically monogamous. In limuluspolyphemus, mating behavior is more variable ranging fi＇om monogamy to polygynandry. here we provide evidence, through a long term behavioral study, that variation in mating behavior is influenced by population density in l. polyphemus. Our study population on two beaches in Connecticut （long Island Sound） have a spawning density 400 times less than that found in Delaware Bay （0.002 females/m2 vs. 0.8 females/m2） but similar operational sex ratios. Between 90%-95% of all spawning females in CT were paired with only one male, thus exhibiting monogamous behavior. In contrast, between 30 and 60% of spawning females in Delaware Bay have more than one mate and produce clutches of eggs with multiple paternities. Male condition played no role in mating behavior in CT populations. We also observed that on average 18% of the females on the spawning beaches are single. These results suggest that population density is an important condition that determines mating behavior. Also, low population density may lead to decreased mate finding ability and lost opportunities for spawning

关键词： limulus Mating behavior Population density Monogamy Polygynandry

表面致密化——一种提高烧结齿轮性能的有效方法

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粉末冶金技术 2005年第1期23卷 62-74页

作者：于洋 linnea Fordén hgansAB

表面致密化与传统的粉末冶金方法相结合 ,可以显著改善烧结齿轮的疲劳及表面磨损性能 ,从而提高齿轮的寿命 ,同时使生产高性能齿轮的总成本降低 ,为用粉末冶金 (PM)方法生产汽车变速箱齿轮提供了更大的可能性。本文着重讲述了使用这种... 详细信息

表面致密化与传统的粉末冶金方法相结合 ,可以显著改善烧结齿轮的疲劳及表面磨损性能 ,从而提高齿轮的寿命 ,同时使生产高性能齿轮的总成本降低 ,为用粉末冶金 (PM)方法生产汽车变速箱齿轮提供了更大的可能性。本文着重讲述了使用这种方法生产高性能PM齿轮的工艺过程 ,同时介绍了测定致密化效果及齿轮性能的几种主要方法 ,并根据工艺过程比较了使用传统的机加工方法及本文所述的方法生产同性能齿轮的成本差别。最后 ,以两个实例分别介绍了使用上述方法对Volvo 85 0系第五挡变速齿轮及Scania载重车变速箱中行星齿轮的研发。

关键词：致密化高性能工艺过程表面磨损齿轮研发烧结高烧有效方法效果

Genetic modification of nitrogen use efficiency in potato and rice plants by introducing a fungal glutamate dehydrogenase

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Genetic modification of nitrogen use efficiency in potato an...

常规豆粕、高蛋白豆粕和低寡糖豆粕饲喂肉鸡的营养价值

2008中国作物学会学术年会

作者： Aoki n Egami T Matsumoto T Kawakami A Abiko T Sasaki h Ohsugi R Graduate School of Agricultural and life Sciences The University of TokyoJapan

The growth and yield of crop plants fundamentally depend on nitrogenous *** inorganic nitrogenous fertilizers(nitrate and ammonia)are applied to farmlands in order to achieve a high yield,a substantial amount of the applied nitrogen is lost from the plant-soil system into surrounding *** excess inorganic nitrogen has been known to cause environmental pollution and ecological *** is important therefore to achieve efficient yields of crops with a low amount of

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饲料工业 2013年第8期34卷 59-64页

作者： K.M.Baker P.l.Utterback C.M.Parsonsh.h.Stein h.h.Stein 伊利诺斯州立大学动物科学系乌尔班纳61801

采用3个肉鸡试验测定高蛋白豆粕(SBM-hP)、低寡糖豆粕(SBM-lO)和常规豆粕(SBM-CV)的饲用价值。这3种豆粕(SBM)的粗蛋白含量(CP)分别为54.9%、53.6%和47.5%。①3种豆粕的氨基酸(AA)标准消化率(SDD)通过在单冠白来航公鸡上采用精准饲喂分... 详细信息

采用3个肉鸡试验测定高蛋白豆粕(SBM-hP)、低寡糖豆粕(SBM-lO)和常规豆粕(SBM-CV)的饲用价值。这3种豆粕(SBM)的粗蛋白含量(CP)分别为54.9%、53.6%和47.5%。①3种豆粕的氨基酸(AA)标准消化率(SDD)通过在单冠白来航公鸡上采用精准饲喂分析法进行测定。结果显示,除赖氨酸外,3种豆粕的氨基酸标准消化率没有差异,高蛋白豆粕比常规豆粕的赖氨酸标准消化率高(P=0.07)。②在第二个试验中,采用公鸡精准饲喂分析法测定每种豆粕的氮校正真代谢能(TMEn)。结果显示,高蛋白豆粕的氮校正真代谢能高于(Pl/kg干物质)。③选用120只308品种商品肉公鸡(平均初始体重为102.6 g)进行14日龄生长表现试验,试验设计采用完全随机化设计法设计。每个处理8个重复,每个重复5只鸡。3种玉米-豆粕型日粮配方设计基于之前试验测定的可消化AA和TMEn值来确定。每种日粮选用一种豆粕,但因为SBM-hP和SBM-lO的可消化氨基酸浓度比SBM-CV的高,所以,SBM-hP和SBM-lO的添加量分别为31.21%和32.60%,而SBM-CV的添加量为38.21%。分别饲喂3种日粮的肉鸡体增重和饲料效率没有显著差异,即表明日粮中SBM-hP和SBM-lO的添加量低于SBM-CV的添加量并不影响肉鸡的生长表现。总之,和SBM-CV相比,SBM-hP和SBM-lO在肉鸡日粮中的添加量较低的原因是这两种来源SBM的营养价值高于SBM-CV的营养价值。

关键词：氨基酸肉鸡高蛋白豆粕低寡糖豆粕氮校正真代谢能

CuPc based organic-inorganic hetero-junction with Au electrodes

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Journal of Semiconductors 2010年第7期31卷 22-25页

作者： Zubair Ahmad Muhammad h.Sayyad Kh.S.Karimov Ghulam Ishaq Khan Institute of Engineering Sciences and Technology TopiNWFP23460Pakistan Department of Mechanical Engineering 20 Symond Street AucklandUniversity of AucklandNew Zealand

A hetero-junction of n-silicon（n-Si） and copper phthalocyanine（CuPc） has been *** current -voltage characteristics were investigated to explain the rectification and conduction *** effect of temperature and humidity on the electrical properties of n-Si/CuPc hetero-junction has also been *** characteristics of the junction have been observed to be temperature and humidity dependent,so it is suggested that this junction can be used as a temperature and humidity sensor.

关键词： inorganic-organic hetero-junction n-Si CuPc

hot nuclear Matter Equation of State and Finite Temperature Kaon Condensation

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作者： (英)n.G.l.哈蒙德

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Chinese Physics letters 2008年第12期25卷 4233-4236页

作者：李昂左维 Schulze h. J. lombardo U. Department of Physics and Institute of Theoretical Physics and Astrophysics Xiamen University Xiamen 361005 Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 InFn-lnS Via Santa Sofia 44 I-95123 Catania and Department of Physics and Astrophysics Catania University. Via Santa Sotia 64 I-95123 Italy

We perform a systematic calculation of the equation of state of asymmetric nuclear matter at finite temperature within the framework of the Brueckner-hartree-Fock approach with a microscopic three-body force. When applying it to the study of hot kaon condensed matter, we find that the thermal effect is more profound in comparison with normal matter, in particular around the threshold density. Also, the increase of temperature makes the equation of state slightly stiffer through suppression of kaon condensation.

关键词： field emission molybdenum dioxide enhancement factor

Structures and characteristics of carbohydrates in diets fed to pigs: a review

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Journal of Animal Science and Biotechnology 2019年第3期10卷 601-617页

作者： Diego M.D.l.navarro Jerubella J.Abelilla hans h.Stein Department of Animal Sciences University of IllinoisUrbana 61801USA Division of nutritional Sciences University of IllinoisUrbana 61801USA

The current paper reviews the content and variation of fiber fractions in feed ingredients commonly used in swine *** serve as the main source of energy in diets fed to *** may be classified according to their degree of polymerization: monosaccharides,disaccharides,oligosaccharides,and *** carbohydrates include sugars,digestible starch,and glycogen that may be digested by enzymes secreted in the gastrointestinal tract of the ***-digestible carbohydrates,also known as fiber,may be fermented by microbial populations along the gastrointestinal tract to synthesize short-chain fatty acids that may be absorbed and metabolized by the *** non-digestible carbohydrates include two disaccharides,oligosaccharides,resistant starch,and non-starch *** concentration and structure of non-digestible carbohydrates in diets fed to pigs depend on the type of feed ingredients that are included in the mixed ***,arabinoxylans,and mixed linked β-(1,3)(1,4)-D-glucans are the main cell wall polysaccharides in cereal grains,but vary in proportion and structure depending on the grain and tissue within the *** walls of oilseeds,oilseed meals,and pulse crops contain cellulose,pectic polysaccharides,lignin,and *** crops and legumes also contain significant quantities of galacto-oligosaccharides including raffinose,stachyose,and ***,understanding the structure,characteristics and measurable chemical properties of fiber in feed ingredients may result in more accurate diet formulations,resulting in an improvement in the utilization of energy from less expensive high-fiber ingredients and a reduction in reliance on energy from more costly cereal grains.

关键词： Carbohydrates Carbohydrate composition Chemical structure Feed ingredients Fiber Pigs

CRACK GROWTh BEhAVIOR In TITAnIUM AllOY TC11 AT ROOM AnD hIGh TEMPERATURES

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Acta Metallurgica Sinica(English letters) 1999年第1期12卷 80-84页

作者： h.F. huang and S.l. liu laboratory of Material Mechanical Properties, Beijing Institute of Aeronautical Materials (BIAM), Beijing 100095, China

This paper presents some new results of a research on the fatigue crack propagation (FCP) behavior in the titanium alloy TC11. Crack propagation tests were carried out at room temperature by center cracked tension (CCT) specimens under three stress ratios of R=0, 0.5, -1, and at 400 by compact tension (CT) and single edged specimens under stress ratios of R=0.1 and -1, respectively. The crack growth rates were compared by using stress intensity factor and effective stress intensity factor. The results show that the effects of stress ratio and ambient temperature on crack growth rates decreased if they were correlated by using the effective stress intensity factor.

关键词： fatigue crack growth crack growth rate titanium alloy