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The roles of rare males in populations of the brine shrimp Artemia parthenogenetica

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Chinese Science Bulletin 1995年第22期40卷 1917-1921页

作者：高明君程继军蔡亚能 College of Marine Life Sciences Ocean University of Qingdao Qingdao 266003 China

The rare males occurring in low numbers in populations of Artemia parthenogenetica may arise from the fusion of two haploid X cells after the second meiotic division. There is no unanimous overview concerning the role and ability of these asexually produced males to hybridize with bisexual females. Bowen et al. first succeeded in crossing 4 rare males originated from India, Japan and France with females of A. franciscana and A. urmiana. In that study, fertilization was confirmed by Mendelian segregation patterns of

关键词： Artemia parthenogenetica rare males crossing experiments isozyme variation.

A wavelength division multiplexer based on plastic surface-relief grating applied to local area communication network

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Optoelectronics Letters 2012年第5期8卷 344-347页

作者：林宝卿翟云庄其仁 College of Information Science&Engineering Huaqiao University

A plastic surface-relief grating as a wavelength division multiplexer is designed and fabricated with the conventional mould pressing technique using the transmission-type fused quartz phase grating as mask pattern and polycarbonate as basal *** experiment results show that in an optimizing process,the plastic surface-relief grating has the highest firstorder diffraction efficiency under adequate groove depth and incident angle,and can be used as the best optical path for wavelength division multiplexing(WDM).We also establish the experiment setup for testing the WDM performance of the plastic surface-relief grating based wavelength division *** results show that the proposed wavelength division multiplexer has the high-stability temperature characteristics,the low insertion loss of less than 5 dB,the large isolation of greater than 20 dB,the low polarization-dependent loss(PDL) of less than 0.4 dB and the relatively steep pass-band *** is a WDM device with good performance,which can be applied in short distance communication.

关键词： experiments Masks Multiplexing equipment Quartz Surfaces Wavelength

Mechanical Behaviors of Silt Rock Subjected to Coupling Static and Impact Loads

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Transactions of Tianjin University 2006年第B09期12卷 205-209页

作者： ZHOU Zilong LI Xibing HONG Liang MA Chunde School of Resources and Safety Engineering Central South University Changsha 410083 China

experiments of silt rock subjected to coupling loads were carried out on tailormade equipment. With a constant dynamic load, the behaviors of eight sets of siltite specimens were investigated with different axial static loads. The experimental results show that the modulus of the specimens under coupling loads increases at first and then decreases with the increase of axial static pressure. The failure model of the specimens also varies. Keeping the dynamic load constant, when the axial static pressure is low, the specimen breaks in two simply. With the increase of axial static pressure, the cone-shaped fragment appeares. When the axial static pressure reaches 90% of the static strength of rock, the specimen smashes into amount of small fragments.

关键词： rock mechanics coupling loads experiments

Jump rule for edge impacts of rolling prisms

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Theoretical & Applied Mechanics Letters 2018年第6期8卷 425-430,I0006页

作者： Zhen Zhao Nannan Wang Caishan Liu School of Aeronautic Science and Engineering Beihang University State Key Laboratory for Turbulence and Complex Systems College of Engineering Peking University

We study experimentally and theoretically the planar dynamics of purely rolling prisms on a rough ramp, where the rolling motion is interrupted intermittently by edge impacts. The experiments were carried out for prisms made of different materials and having different geometries. We found that the angular velocities of the rolling prisms are material-independent, but they change significantly with their geometry. We modelled the dynamics of edge impacts by considering a socalled detachment front propagating across the contact interface. The detachment front represents the moving boundary between a detached region and a stress region that coexist within the interface plane. The theoretical analysis indicates that the detachment front can be characterized by a scale number, whose value converges to 0.4050 for prisms having large number of edges. A new jump rule for edge impacts is then developed, by which we can accurately reproduce the experimental observations, and explain why the motion of the prism is material-independent.

关键词： Surface impact Jump rule experiments

EXPERIMENTAL STUDIES ON THE ROLE OF PLANKTIVOROUS FISHES IN THE ELIMINATION OF MICROCYSTIS BLOOM FROM DONGHU LAKE USING ENCLOSURE METHOD

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Chinese Journal of Oceanology and Limnology 1996年第3期14卷 193-204页

作者：谢平 Donghu Experimental Station of Lake Ecosystems CERN Institute of Hydrobiology Chinese Academy of Sciences Wuhan

The hypertrophic subtropic Donghu Lake’s dense water bloom(of mainly Microcystis Anaabaena andOscillatoria)that occurred annually from the beginning of the 1970s, has disappeared since 1985. The infiuenceof planktivorous fishes (silver and bighead carps) on the water bloom was studied for three years usingthe enclosure method. The enclosures stocked densely with bighead and/or silver carp were free of waterbloom during the experimental period. The water bloom that appeared in the fish-free enclosures was completelyeliminated in 10-20 days by introduction of silver and/or bighead carp(grass carp was not effectivein controlling water bloom).This study showed clearly that grazing pressure by planktivorous fishes is a keyfactor in eliminating water bloom from the lake.

关键词： enclosure experiments water bloom hypertrophic lake planktivorous fishes grazing pressure

Noise color influence on escape times in nonlinear oscillators-experimental and numerical results

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Theoretical & Applied Mechanics Letters 2023年第2期13卷 149-158页

作者： Thomas Breunung Balakumar Balachandran Department of Mechanical Engineering University of MarylandCollege ParkMD 20742United States

The interplay between noise and nonlinearites can lead to escape *** nonlinear phe-nomena have been observed in various applications ranging from climatology to biology and *** reasons of computational ease,in most studies,Gaussian white noise is ***,this noise model is not physical due to the associated infinite energy ***,the authors present extensive experimental investigations and numerical simulations conducted to examine the impact of noise color on escape times in nonlinear *** a careful parameterization of the numerical simulations,the authors are able to make quantitative comparisons with experimental *** the experi-ments and simulations,it is illustrated that the noise color can drastically influence escape times and escape probability.

关键词： Colored noise Non-Gaussian excitation experiments Escape times

Experimental study on shear behavior of reinforced concrete beams with web horizontal reinforcement

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Frontiers of Structural and Civil Engineering 2014年第4期8卷 325-336页

作者： Dong XU Yu ZHAO Chao LIU Department of Bridge Engineering Tongji University Shanghai 200092 China

In determining the shear capacity of reinforced concrete beams, current codes do not provide any calculation method to evaluate the influence of web horizontal reinforcement, although they exist as structural reinforcements （or skin reinforcement）. The present paper comprises results of 11 reinforced concrete beams in an effort to investigate the influence of web horizontal reinforcement on the shear behavior of reinforced concrete beams. The primary design variables are the shear-span-depth ratio, different reinforcement ratio of stirrups and web horizontal reinforcement. Influence of web horizontal reinforcement on crack patterns and failure mode was studied. It was found that web horizontal reinforcement can increase the shear capacity of the beams and restrain growth of inclined cracks effectively. Test results are very valuable, as very few references of shear tests can be found focusing on the effect of web horizontal reinforcement on the shear capacity of the beams.

关键词： reinforced concrete beam shear strength web horizontal reinforcement experiments

Changes in wheat starch grains using different cooking methods: Insights into ancient food processing techniques

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科学通报 2013年第S1期58卷 82-89页

作者： DAI Ji YANG YiMin WANG Bo WANG ChangSui JIANG HongEn Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of Sciences Department of Scientific History and Archaeometry University of Chinese Academy of Sciences Xinjiang Uygur Autonomous Region Museum

We investigate the morphological changes in starch grains from wheat(Triticum aestivum) using different cooking methods(boiling, steaming, frying, and baking). We compare the cooked starch grains with starch grains from ancient wheat flour cakes(Astana Cemetery, Turpan Basin, Xinjiang, China) to determine the cooking techniques used by people in Xinjiang 1200 years ago. Heat and water content affect starch grains when different cooking methods are used. Boiling and steaming results in the collapse of wheat starch grains accompanied by extreme swelling, curved granules, pasting, almost full gelatinization, a distinct extinction cross and vague granule outlines. Frying and baking cause less swelling, fewer curved granules, less pasting and only partial gelatinization of wheat starch grains, but the extinction lines are still distinct and the outlines of granules relatively clear. The pale brown substances on the starch grains make starch from baked-wheat products distinct from those cooked using other methods.

关键词： cooking experiments food processing starch grains analysis Triticum aestivum

RECENT DOMESTIC PROGRESS IN SPACE CRYSTALLIZATION OF PROTEINS

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空间科学学报 1998年第S1期18卷 98-103页

作者： BI Ru-chang (Institute of Biophysics, The Chinese Academy of Sciences, Beijing 100101)

The advances of protein crystal growth in microgravity are limited by its low success rate of space crystallization experiments. Our recent efforts have concentrated on exploration of the ways to increase the success rate of the *** corresponding studies include structural comparisons of space- and Earthgrown protein crystals, numerical simulations of solute transport in protein crystallizer, optimization of protein crystailization conditions and improvement of crystallization techniques used. These studies show that the success rate of space protein crystallization could be improved by different ways.

关键词： Protein Crystal growth Microgravity Success rate of experiments