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Does social context affect boldness in juveniles？

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Current Zoology 2017年第6期63卷 639-645页

作者： Siobhan loftus Jost BORCHERDING Institute of Zoology of the University of Cologne Department of General Ecology & Limnology Ecological FieldStation Grietherbusch D-50923 Cologne Germany

Differences in boldness are common between populations or between related species and are discussed as part of individual coping style, personality, or behavioral syndrome. Boldness has been found to be dependent on experience, social, and environmental contexts. The major aim of the present study was to establish an experimental environment that would allow analyzing the risk-taking behavior of 2 competing invasive goby species. Neogobius melanostomus was more active in the absence of a predator Sander lucioperca than N. fluviatilis and clearly spent more time ＂swimming＂ and ＂feeding＂ than N. fluviatilis. In addition, N. melanostomus was always faster than N. fluviatilis both when leaving the shelter and reaching offered food. Based on the different behaviors recorded, species-specific boldness scores were established using a principal component analysis. Although there was no overall difference in boldness scores between the 2 species, both competitive conditions and the effect of the predator played significant roles as factors influencing boldness. Neogobius melanostomus was more affected by the presence/absence of the predator than the social circumstances. Neogobius fluviatilis, on the other hand, was more active and bolder in competitive situations. However, when alone, N. fluviatilis was rather inactive and displayed altogether shy behavior, independent of the presence/ absence of the predator. Thus, the study confirms the prediction that there are differences in behavior and behavioral plasticity, and therein predator-avoidance strategies, between ecologically similar species of goby living in sympatry. We argue that these differences may be related to differential habitat use of both invasive species that presently dominate the fish community in the Lower Rhine.

关键词： boldness score Neogobius fluviatilis Neogobius melanostomus predator-avoidance social environment.

Investigation　of　Deuterium　Isotope　Effects　in　the　Carbon　Dioxide　Reforming　of　Methaneto　Syngas　over　Rhodium　Catalysts

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Chinese Chemical Letters 1996年第11期7卷 1047-1050页

作者： Wang, HY Au, ct XIAMEN UNIV DEPT CHEMXIAMEN 361005PEOPLES R CHINA HONG KONG BAPTIST UNIV DEPT CHEMKOWLOONHONG KONG

Deuterium isotope effects in the CO2-reforming of methane to syngas were firstinvestigated over SiO2-supported rhodium catalysts. Normal deuterium isotop effect was morenoticeable on the methane conversion reaction than on the CO formation reaction, while there wasno such effect on the CO2 conversion reaction. It can be concluded that the dissociation of the C-Hbond in methane is a key mp and some CO is formed by the reverse water-gas shift reaction.

关键词： over Rhodium Syngas Investigation Deuterium Carbon

Synthesis of Bis(macrocyclic) Polyamines Containing Rigid Bridging Groups

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Chinese Chemical Letters 1997年第3期8卷 209-212页

作者： Wang, HJ Wu, ct WUHAN UNIV DEPT CHEMWUHAN 430072PEOPLES R CHINA

This paper deals with the synthesis of three new symmetrical bis (macrocylic) polyamines and their dinuclear copper(I) complexes. All these compounds were identified by elemental analysis and spectral analysis(IR,H-1 ... 详细信息

关键词： HCl Synthesis of Bis macrocyclic Polyamines Containing Rigid Bridging Groups HNMR

Syntheses of New Crowned Indolinospirobenzopyrans

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Chinese Chemical Letters 1997年第4期8卷 285-288页

作者： Wu, XY Wu, ct WUHAN UNIV DEPT CHEMWUHAN 430072PEOPLES R CHINA

Two new indolinospirobenzopyrans bearing monoaza-benzo-15-C-5 were synthesized. And they were determined by IR, H-1 NMR and MS.

关键词： RECOGNITION INDUCED ISOMERIZATION SPIROBENZOPYRANS

The Rewards of Fundamental Atomic Spectrometry Research

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光谱学与光谱分析 2000年第2期20卷 156-159页

作者： Walter Slavin Bonaire Technologies Ridgefield,ct 06877 USA Bonaire Technologies Ridgefield CT 06877 United States

Atomic spectrometry research is the life blood of the atomic spectrometry instrument *** instrument designer can be expected to innovate in the execution of instrumentation and should be expected to be the expert in optical,electronic and software *** new technology has required too long a period of gestation to be compatible with commercial time scales and *** in the past decade,the pressure from stockholders for increased return on investments has put increasingly strong pressure on management to reduce expenses and focus increasingly on projects that guarantee a fast *** pressure falls particularly heavily on the larger companies;the same companies that a decade or more ago were the ones that brought the more far reaching and expensive new concepts to market. Fundamental research in atomic spectrometry has been accomplished in the past several decades mostly in the academic environment and in research institutions that are Federally *** of the Federally funded research institutions have been forced to alter their missions to more tangible and immediate goals,and many have also seen severe financial reductions.

关键词： The Rewards of Fundamental Atomic Spectrometry Research

Ice Induced Low Temperature Fatigue Crack Propagation in Offshore Structural Steel A131

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China Ocean Engineering 1998年第3期13卷 275-284页

作者： Duan, ML Gao, ZJ Liu, ct China Classificat Soc Beijing 100006 Peoples R China Chinese Acad Sci Inst Mech Beijing 100080 Peoples R China

To investigate the low temperature fatigue crack propagation behavior of offshore structural steel A131 under random ice loading, three ice failure modes that are commonly present in the Bohai Gulf are simulated according to the vibration stress responses induced by real ice loading. The test data are processed by a universal software FCPUSL developed on the basis of the theory of fatigue crack propagation and statistics. The fundamental parameter controlling the fatigue crack propagation induced by random ice loading is determined to be the amplitude root mean square stress intensity factor K-arm. The test results are presented on the crack propagation diagram where the crack growth rate da/dN is described as the function of K-arm. It is evident that the ice failure modes have great influence on the fatigue crack propagation behavior of the steel in ice-induced vibration. However, some of the experimental phenomena and test results are hard to be physically explained at present. The work in this paper is an initial attempt to investigate the cause of collapse of offshore structures due to ice loading.

关键词： low temperature fatigue crack propagation offshore structure steel A131 ice load random vibration

SYNTHESIS AND CHARActERIZATION OF HETEROBIMETALLIC COMPLEXES:(Cp_2LnOCH_2C_6H_5)Cr(CO)_3(Ln=Gd,Dy,Yb,Y)

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Chinese Chemical Letters 1995年第3期6卷 261-262页

作者： Qian, ct Guo, JH Acad Sinica Shanghai Inst Organ Chem Organomet Chem Lab Shanghai 200032 Peoples R China

Heterobimetallic complexes in which chromium and lanthanide metals were bridged with difunctional benzyloxide group (Cp2LnOCH2C6H5)Cr(CO)3 (Ln=Gd. Dy. Yb. Y). were synthesized The complexes were characterized by eleme... 详细信息

关键词： Dy AND SYNTHESIS CHARActERIZATION HETEROBIMETALLIC OF Gd COMPLEXES Yb Cr

Mechanics of a Grip System of Three-Key-Board Hydraulic Tongs Developed for Offshore Oil Pipe Lines

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China Ocean Engineering 1999年第1期14卷 101-108页

作者： Zhao, JY Guo, AJ Ding, KQ Liu, ct Petr Univ China Shangdong 257012 Peoples R China Chinese Acad Sci Inst Mech Beijing 100080 Peoples R China

This paper carries out the analysis of mechanics of a grip system of three-key-board hydraulic tongs developed for offshore oil pipe lines which has been successfully used in oil fields in China. The main improvement of this system is that a lever frame structure is used in the structural design, which reduces greatly the stresses of the major components of the oil pipe tongs. Theoretical analysis and numerical calculation based on thirteen basic equations developed Show that the teeth board of the tongs is not easy to slip as frequently happens to other systems and is of higher reliability.

关键词： grip system three-key-board hydraulic tongs offshore oil pipe lines stress analysis

Hemsleyasine, a New Norditerpenoid Alkaloid from the Roots of Aconitum Hemsleyanum ***

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Chinese Chemical Letters 1997年第2期8卷 137-140页

作者： Xu, QY Wang, FP Tan, TCM Che, ct W CHINA UNIV MED SCI SCH PHARMDEPT CHEM MED NAT PRODCHENGDU 610044PEOPLES R CHINA HONG KONG UNIV SCI & TECHNOL DEPT CHEMHONG KONGHONG KONG

A new norditerpenoid alkaloid, hemsleyasine 1, has been isolated from the roots of Aconitum hemsleyanum var. circinatum W. T. Wang and its structure was established by spectral methods (H-1- and C-13-NMR, H-1 COSY, CO... 详细信息

关键词： NUCLEAR MAGNETIC-RESONANCE