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Asian Herpetological Research 2013年第1期4卷 56-61页

作者： zhiping mi College of Life Science China West Normal University

In many anurans, the forelimb muscles of males are used to grasp females and are often heavier than those of females despite the larger female body size. Such sexual dimorphism in forelimb musculature is thought to result from sexual selection. In addition, the hindlimbs of frogs and toads play an important role in the reproductive process as amplectant males can expel rivals with robust hindlimbs through kicking. In this study, the sexual dimorphism in dry mass for six hindlimb muscles of the Asiatic toad （Bufo gargarizans） was investigated. The results showed that, when controlled for body size, the hindlimb muscle mass of males significantly exceeded that of females for every muscle. The hindlimb muscle mass of amplectant males was also significantly larger than that of non-amplectant males. These results suggested that if strong hindlimb muscles could improve mating success of males, sexual selection would promote the evolution of dimorphism in this character.

关键词： Bufo gargarizans hindlimb muscle sexual dimorphism sexual selection

Skeletochronological Study of Age,Longevity and Growth in a Population of Rana nigromaculata(Amphibia:Anura) in Sichuan,China

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Asian Herpetological Research 2012年第3期3卷 258-264页

作者： min MAO Yan HUANG zhiping mi Yanhong LIU Caiquan ZHOU Key Laboratory of Southwest China Wildlife Resources Conservation (ministry of Education) China West Normal University Institute of Rare Animals and Plants China West Normal University

A skeletochronological study was conducted for the age, longevity and growth of a Rana nigromaculata population in northeastern Sichuan, China. Of 139 specimens, 119(68 males and 51 females) exhibited distinct arrested growth lines in phalanges. Age at first reproduction was found to be two years of age for males and three for females. Maximum longevity was estimated to be at least six years in males and seven years in females. Average age did not differ between males and females. Breeding females were significantly older than breeding males. Females were larger in body size and heavier in body mass than males. Age was not correlated with body size and body mass in males, but a significant correlation was found among age, body size and body mass in females. The growth curve appeared significantly different between the sexes, with a higher growth rate throughout life and a larger asymptotic size in females. Moreover, analysis of the growth model indicated that the population studied was relatively stable.

关键词： age structure Rana nigromaculata population skeletochronology

Skeletochronological Study on Age Structure of a Chinese Endemic Frog(Rana omeimontis)

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Asian Herpetological Research 2012年第3期3卷 252-257页

作者： Wencao LIU Yanhong LIU Yan HUANG zhiping mi Cao LI Key Laboratory of Southwest China Wildlife Resources Conservation (ministry of Education) China West Normal University Department of Life Science and Technology Yibin College

We used skeletochronology to estimate age structure of the Omei Wood Frog, Rana omeimontis, from southwestern *** age differed significantly between males and *** at sexual maturity in both males and females was 1 year. Longevity was 6 and 7 years for males and females, respectively. Average body size differed significantly between the sexes, with females being larger than males. A non-significant correlation between age and body size was found within each sex in this population. The ANCOVA analysis revealed that females also had larger body size than males when the effect of age was controlled.

关键词： skeletochronological method Rana omeimontis age structure sexual size dimorphism

Asymmetry of Testes in Guenther's Frog,Hylarana guentheri(Anuar:Ranidae)

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Asian Herpetological Research 2011年第4期2卷 234-239页

作者： Yanhong LIU Wenbo LIAO Caiquan ZHOU zhiping mi min MAO Key Laboratory of Southwest China Wildlife Resources Conservation of ministry of Education China West Normal University Institute of Rare Animals and Plants China West Normal University

Testes size in most animals commonly shows directional asymmetry. In birds, the left testis mass is usually larger than the right one, but the reports on the testes asymmetry in anurans are very few. Moller （1994） hypothesized that the right testis serves a compensatory role and increases in size when the left one is defective, and further suggested that testes asymmetry may be a reliable indicator of individual body condition. In this paper, we tested the compensation hypothesis in the Guenther＇s frog, Hylarana guentheri. From 60 sampled males, we found that there was a significant directional asymmetry in testes mass, with the left testis size being significantly correlated with relative testes asymmetry, providing evidence that the right testis had a compensatory function. However, testes mass and asymmetry were not correlated with body condition. Hence, we found no evidence that testes asymmetry in the Guenther＇s frog reflected male condition, and male age was also not related to testes mass or asymmetry.

关键词： directional testes asymmetry compensation hypothesis body condition Hylarana guentheri

Altitudinal Variation in Digestive Tract Length in Yunnan Pond Frog (Pelophylax pleuraden)

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Asian Herpetological Research 2013年第4期4卷 263-267页

作者： Shangling LOU Yanhong LI Long JIN zhiping mi Wenchao LIU Wenbo LIAO Key Laboratory of Southwest China Wildlife Resources Conservation (ministry of Education) China West Normal University Institute of Rare Animals and Plants College of Life Sciences China West Normal University

The digestive tract plays an important role in digestion and the acquisition of food energy. Understanding the impact of abiotic environments on digestive tract morphology is especially important for evolution of digestive tract across different environments. Here, we investigated altitudinal variation in digestive tract length in the Yunnan Pond Frog （Pelophylaxpleuraden） across five populations ranging from 1413 m to 1935 m a.s.1, in Ningnan County, Sichuan province in western China. Frogs were collected during the breeding season, from 1-5 June 2012. Our results revealed that females had longer digestive tract and relative digestive tract （i.e. digestive tract length / body size） lengths in com- parison to males, on average, but the differences between them decreased with increasing altitude. Digestive tract and relative digestive tract lengths increased with increasing altitude suggesting that a higher proportion of indigestible ma- terials may be consumed at high-altitude sites and result in a relative increase in digestive tract dimensions.

关键词： altitudinal gradient digestive tract Pelophylax pleuraden Ningnan county

Crypsis is associated with smaller brains in anurans

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Crypsis is associated with smaller brains in anurans

第十三届全国野生动物生态与资源保护学术研讨会暨第六届中国西部动物学学术研讨会

作者： Maojun Zhong Yi Luo Shengnan Yang zhiping mi Wenbo Liao Alexander Kotrschal Key Laboratory of Southwest China Wildlife Resources Conservation China West Normal University Zoological Institute Stockholm University

Large brains evolve when the cognitive benefits of additional neural tissue outweigh its energetic ***‘cognitive buffer’hypothesis states that such cognitive benefits allow species to survive in complex environments due to their ability to devise novel or flexible behavioural *** in several taxa larger brains relative to body size are associated with a range of cognitively challenging ecological *** active predator evasion

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典型气流床煤气化技术对煤质的要求探讨

煤化工 2023年第5期51卷 42-44页

作者：马乐波米治平武彬古杰匡建平宁夏神耀科技有限责任公司宁夏银川750011 延安能源化工(集团)子长化工有限责任公司陕西延安717300

气化反应过程与煤的性质和组成有着密切的关系,具体到某一种气化技术,往往对煤质有某些特定的要求。结合宁夏某煤化工基地典型的耐火砖水煤浆及水冷壁干煤粉气化装置用煤实际情况,并在查阅相关文献的基础上,分析了两种典型的气流床气化... 详细信息

气化反应过程与煤的性质和组成有着密切的关系,具体到某一种气化技术,往往对煤质有某些特定的要求。结合宁夏某煤化工基地典型的耐火砖水煤浆及水冷壁干煤粉气化装置用煤实际情况,并在查阅相关文献的基础上,分析了两种典型的气流床气化技术对煤质水分、灰分、灰熔融性温度、黏温特性的指标要求;根据分析结果,探讨了陕西子长地区几种典型煤样的单独用煤建议和配煤方案,为潜在的煤气化项目提供用煤指导。

关键词：气流床水煤浆气化干煤粉气化煤质配煤

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气化渣残碳量方法的对比研究

广州化工 2024年第22期52卷 84-87,94页

作者：马丹丹张亚宁米治平匡建平古杰宁夏神耀科技有限责任公司宁夏银川750000 延安能源化工(集团)子长化工有限责任公司陕西延安716000

煤炭清洁高效利用已是中国能源发展的必然趋势,煤气化技术因其煤种适应性好、气化效率高、环保性能优越等优点,为工业运行的主流技术,同时是清洁高效利用的关键技术。气化渣是煤气化的副产物,而气化渣的残碳量可以体现煤气化反应过程的... 详细信息

煤炭清洁高效利用已是中国能源发展的必然趋势,煤气化技术因其煤种适应性好、气化效率高、环保性能优越等优点,为工业运行的主流技术,同时是清洁高效利用的关键技术。气化渣是煤气化的副产物,而气化渣的残碳量可以体现煤气化反应过程的转化效率和气化炉的运行状态。开展对气化渣的残碳量的测定方法的研究对提高煤气化效率和优化气化炉结构设计具有重要意义。本文对比研究了传统烧失量法、单气氛热重法和双气氛热重法三种方法对气化渣(粗渣和细渣)残碳量的测定结果,发现双气氛热重法比传统烧失量法更便捷,且测量值更准确。

关键词：气化渣残碳量烧失量单气氛双气氛

microstructure and Tensile Properties of Spray-deposited IC6 Alloy

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Journal of Materials Science & Technology 1998年第2期14卷 143-146页

作者： mi, Guofa Li, Zhou Tian, Shifan Zhao, Xianguo Luo, zhiping Zeng, Songyan Li, Qingchun Inst Aeronaut Mat Beijing 100095 Peoples R China Harbin Inst Technol Sch Mat Sci & Engn Harbin 150001 Peoples R China

The microstructure and mechanical properties of a Ni//3 Al based Ni-Al-Mo superalloy-IC6 which possesses low impurity content and high density by spray deposition technique have been studied. The results indicate that the IC6 alloy has good tensile strength and elongation both at room and intermediate temperatures. (Edited author abstract) 6 Refs.

关键词： Nickel alloys

Theoretical and metrical standardization of strain rate sensitivity index

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Science China(Technological Sciences) 2007年第6期50卷 714-735页

作者： SONG YuQuan GUAN zhiping LI ZhiGang WANG mingHui Superplastic and Plastic Research Institute Jilin University Changchun 130022 China Superplastic and Plastic Research Institute Jilin University Changchun 130022 China Superplastic and Plastic Research Institute Jilin University Changchun 130022 China Superplastic and Plastic Research Institute Jilin University Changchun 130022 China

Strain rate sensitivity index m is one of the vital mechanical parameters for deter- mining material superplasticity. In this paper, the existing formulae for measuring m value are reviewed, and it is found that the m values can be classified into three classes: mi under constant length, mv under constant velocity, and mP under con- stant load. The constraint equation of the generalized m value is established ac- cording to the tensile constitutive equation and the basis theory for plastic me- chanics. Based on three typical deformation paths, the m value is redefined. Fur- thermore, from the formula of generalized m value, the formulae for measuring mi, mv and mP are theoretically deduced. The precise methods with numerical simula- tion are presented. The results prove that the m value is a non-constant and its dependence on ε changes with the deformation path. Under different deformation paths, the m values calculated from the same formula are different. Using different formulae, the m values under the same deformation path are also different. There- fore, deformation path and corresponding formula should be given during the measurement of the m value. Moreover, it is explained theoretically and experi- mentally that why the mv value under constant velocity is sometimes negative but the mP value under constant load is sometimes lager than 1. The aim of the analysis and measurement of the m value is to facilitate the study on the relationship be- tween macroscopical mechanical laws and microscopic physical mechanisms during superplastic deformation.

关键词： superplasticity, strain rate sensitivity index, tensile deformation