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The influence of female age on male mating preference and reproductive success in cabbage beetle, Colaphellus bowringi

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Insect Science 2014年第4期21卷 515-522页

作者： Xing-Ping Liu Hai-Min He Fang-sen xue Institute of Entomology Jiangxi Agricultural University Nanchang Key Laboratory of Crop Physiology Ecology and GeneticBreeding Nanchang China

The influence of female age on male mating preference and reproductive success has been studied using a promiscuous cabbage beetle, Colaphellus bowringi Baly （Coleoptera： Chrysomelidae）. In a simultaneous choice test, middle-aged females had significantly greater mating success than young and old females. In single pair trials, when paired with middle-aged virgin males, middle-aged females mated faster, copulated longer, and had greater fecundity and fertility than young or old females, while the longevity of males was not significantly affected by female age. This study on C. bowringi suggests that middle-aged females are more receptive to mating, which can result in the highest male reproductive success.

关键词： age behavioral responses Colaphellus bowringi Baly mate preference,reproductive fitness

An efficient and green preparation of 5-aminophosphonate substituted pyrimidine nucleosides under solvent-free conditions

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Chinese Chemical Letters 2010年第10期21卷 1191-1194页

作者： Xin Ying Zhang Ying Ying Qu xue sen Fan School of Chemistry and Environmental Sciences Henan Key Laboratory for Environmental Pollution Control Henan Normal University Xinxiang 453007 China

An environmentally benign and highly efficient one-pot preparation of α-aminophosphonates under solvent-free conditions was developed. By employing this method, 5-aminophosphonate substituted pyrimidine nucleosides were synthesized in good to excellent yields starting from 5-forrnyl-2＇-deoxyuridine, aniline and dimethylphosphite.

关键词： Aminophosphonate 5-Substituted pyrimidine nucleoside Solvent-free reaction Green synthesis

Particle Emission-Dependent Timing Noise of Pulsars

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Chinese Physics Letters 2011年第1期28卷 230-232页

作者： LIU Xiong-Wei NA xue-sen XU Ren-Xin QIAO Guo-Jun School of Physics and State Key Laboratory of Nuclear Physics and Technology Peking University Beijing 100871

Though pulsars spin regularly, the differences between the observed and predicted ToA （tune of arrival）, known as ＂timing noise＂, can still reach a few milliseconds or more. We try to understand the noise in this study. As proposed by Xu and Qiao in 2001, both dipole radiation and particle emission would result in pulsar braking. Accordingly, possible fluctuation of particle current flow is suggested here to contribute significant ToA variation of pulsars. We find that the particle emission fluctuation could lead to timing noise which cannot be eliminated in timing process and that a longer period fluctuation would arouse a stronger noise. The simulated timing noise profile and amplitude are in agreement with the observed timing behaviors on the timescale of years.

关键词： Timing Time Noise

Improved formation density measurement using controllable D-D neutron source and its lithological correction for porosity prediction

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Nuclear Science and Techniques 2022年第1期33卷 24-34页

作者： Li Zhang Hua-Wei Yu Yang Li Wen-Bao Jia Xiao Han xue-sen Geng College of Resources Shandong University of Science and TechnologyTai’an 271019China School of Geosciences China University of PetroleumQingdao 266580China College of Mechanical and Electronic Engineering Shandong Agricultural UniversityTai’an 271018China Department of Nuclear Science and Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China

Controllable D-D neutron sources have a long service life,low cost,and *** are favorable prospects for its application in geophysical well logging,since traditional chemical radioactive sources used for well logging pose potential threats to the safety of the human body and *** paper presents an improved method to measure formation density that employs a D-D neutron *** addition,the lithological effect on the measured density was removed to better estimate the formation ***,we investigated the spatial distribution of capture gamma rays through Monte Carlo simulations as well as the relationship between the ratio of capture gamma ray counts and formation density to establish theoretical support for the design of density logging tools and their corresponding data processing ***,we obtained the far to near detector counts of captured gamma rays for an optimized tool structure and then established its correlation with the density and porosity of three typical formations with pure quartz,calcite,and dolomite ***,we determined the values for correcting the densities of sandstone and dolomite with the same porosity using limestone data as the reference and established the equations for calculating the correction values,which lays a solid foundation for accurately calculating formation *** observed that the capture gamma ray counts first increased then decreased and varied in different formations;this was especially observed in high-porosity *** the same lithologic conditions(rock matrix),as the porosity increases,the peak value of gamma ray counts moves toward the neutron *** different detector-source distances,the ratio of the capture gamma ray counts was well correlated with the formation *** equation of the formation density conversion was established based on the ratio of capture gamma ray counts at the detector-source distances of 30 cm and 65 cm,and the calculate

关键词： Density measurement D-D neutron source Lithological correction Porosity prediction

Non-viral gene delivery carrier of probe ty[pe host molecule--Interactions between DNA and β-cyclodextrin derivative complexes(I)

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Chinese Science Bulletin 2006年第5期51卷 530-535页

作者： LIU Tao CHEN Long HOU sen xue Yonglai FENG Xizeng Key Laboratory of Bioactive Materials Ministry of Education Collegeof Life Science Nankai University Tianjin 300071 China

A host type non-virus gene delivery car- rier, phenanthroline-β-cyclodextrin derivative host molecule, was produced which can be used as mo- lecular probe. Interactions between DZY-1 and DNA were investigated by electrophoresis assay. Hind III enzyme inhibition assay was carried out using DNA condensates induced by host molecules or host- guest molecule complexes to explore their ability to inhibit enzyme digestion. Micro-structure of DNA condensates induced by host molecules and host-guest molecule complexes was observed by scanning electron microscope (SEM). Our work in- dicates the delivery mechanism of DZY-1 used as a gene delivery carrier and also provides a method to design and produce non-virus gene delivery carriers.

关键词： DNA 邻二氮杂菲-β-环糊精衍生物非病毒性基因传输载体琼脂凝胶电泳扫描电子显微镜相互作用

Laboratory evaluation of flight activity of the common cutworm, Spodoptera litura （Lepidoptera： Noctuidae）

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Insect Science 2010年第1期17卷 53-59页

作者： Ye-Gou Tu Kong-Ming Wu Fang-sen xue Yan-Hui Lu State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant Protection Chinese Academy of Agricultural Sciences Beijing Institute of Entomology Jiangxi Agricultural University Nanchang China

The flight activity of Spodoptera litura in tethered conditions is evaluated using a computer-mediated flight-mill in the laboratory. The 3-4-day-old moths fly longer and farther than those of other ages. Male and female moths exhibit similar flight activity. Mating status does not influence the flight duration and distance of 2-day-old females. However, these two flight parameters with a 6-day-old mated female is significantly lower than that of tmmated ones. The optimum temperature for flight ranged from 16-24℃, whereas the optimum RH ranged from 60%--100%. During 72-h period, the total flight duration and distance of 1-day-old male and female moths were 19.6 h （± 5.8） and 83.3 km （± 28.4）, and 24.0 h （± 7.0） and 105.4 km （± 37.4）, respectively. These results indicate that S. litura has a great potential to undertake long-distance migratory flights.

关键词： Spodoptera litura flight activity tethered-flight

Mating behavior of the cabbage beetle, Colaphellus bowringi （Coleoptera： Chrysomelidae）

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Insect Science 2010年第1期17卷 61-66页

作者： Xing-Ping Liu Hai-Min He Xian-Ju Kuang Fang-sen xue Institute of Entomology Jiangxi Agricultural University Key Laboratory of Crop Physiology Ecology and Genetic Breeding Key Laboratory of Physiology Ecology and Cultivation of Double Cropping Rice Ministry of Agriculture Nanchang China

Circadian mating rhythms, mating frequency, mating duration, and the effect of mating duration on fecundity and fertility in the cabbage beetle, Colaphellus bowringi were investigated in the laboratory. Mating occurred throughout the 24-h cycle but the majority of copulations occurred in the photophase with two apparent peaks, one at 8：00 and another at 16：00. Mating frequency observations for 10 consecutive days indicated that pre-mating period of C. bowringi was about 4 days, and pairs mated an average of 5 times per day and an average of 40 times during the first 10 days. There was a negative correlation between mating frequency and mating duration during the consecutive mating. The mean duration of the first copulation （136.24± 4.62 min） was significantly longer than those of the second （57.87 ± 2.03 min）, third （53.05 ±2.05 min） and fourth copulation （30.86 ± 2.98 min）. Fecundity showed a slight increase with increasing mating duration but no significant difference among treatments. However, fertility was significantly influenced by the mating duration in this species. Mating of 20-min duration did not produce viable eggs. The mean percentage of fertile eggs with completed mating duration （204.43±18.96 min, 56.75% fertile eggs） was significantly higher than those with 60 min （39.55%） and 30 min （17.91%） mating duration, suggesting that the longer mating duration might be associated with transfer of more sperm that are used to increase the fertility of eggs.

关键词： circadian rhythm Colaphellus bowringi fecundity fertility mating duration mating frequency

Self-assemble construction of hetero-structured Co(OH)_(2)/MXene aerogel toward Li-S batteries as a self-supported host and bifunctional catalyst

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Rare Metals 2024年第11期43卷 5652-5663页

作者： Yang Liu Ke Tan sen Liu Xu Zhang Mao-Qiang Shen xue-sen Liu Xin-Yue Gao Lin-Rui Hou Chang-Zhou Yuan School of Materials Science&Engineering University of JinanJinan 250022China

The shuttling diffusion of polysulfides is a bottleneck that seriously limits the performance of Li-S *** construction of sulfur cathodes with reliable trapping ability of polysulfides is the key to overcome such ***,a hierarchical porous architecture,i.e.,Co(OH)_(2)sheets bonded Ti_3C_(2)T_x MXene aerogel(Co(OH)_(2)/MXA),is constructed via a facile selfassembled approach and used as an efficient free-standing polysulfides *** interconnected three-dimensional(3D)porous network with void space and strong interfacial interaction not only enables high sulfur loading but facilitates fast ion and electron *** and theoretical results confirm the hetero-framework exhibits outstanding immobilization and conversion ability for polysulfides due to its polar surface and bifunctional catalytic activities toward both formation and decomposition of *** optimized Co(OH)_(2)/MXA cathode delivers excellent rate capability(407 mAh·g^(-1)at 5C)with a sulfur loading of 2.7 mg·cm^(-2),and ultra-stable cycling performance as an extremely small capacity decay of~0.005%per cycle within 1700 cycles at 1C is achieved with a high sulfur loading of 6.7 mg·cm^(-2).More significantly,our design structural/componential methodology here promises the MXene-based aerogel electrodes for LiS batteries and beyond.

关键词： MXene aerogel Co(OH)_(2)sheets Hetero-architecture Self-standing hosts Li-S batteries

Synthesis of 1,2-allenic ketones through oxidation of homopropargyl alcohols with CrO_3(cat.)/TBHP under MWI

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Chinese Chemical Letters 2011年第3期22卷 268-271页

作者： Xin Ying Zhang Ying Ying Qu Yang Yang Wang xue sen Fan School of Chemistry and Environmental Science Henan Key Laboratory for Environmental Pollution Control Henan Normal University Xinxiang 453007 China

A CrO3 catalyzed oxidation of homopropargyl alcohols with tert-butyl hydroperoxide under microwave irradiation was found to be an efficient and rapid alternative for the preparation of 1,2-allenic *** advantages of th... 详细信息

关键词： Allenic ketones Oxidation Microwave irradiation Chromium(Ⅵ) oxide tert-Butyl hydroperoxide