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Chinese Journal of Polymer Science 2021年第2期39卷 237-248,I0008页

作者： Xiao-He Ren Gao-Hui Sun lei-chao Wang Rong-Rong Chen Jun Wang Shi-Hui Han Key Laboratory of Superlight Material and Surface Technology of Ministry of Education Harbin Engineering UniversityHarbin 150001China College of Material Science and Chemical Engineering Harbin Engineering UniversityHarbin 150001China

New ambient sound absorption material,lightweight isocyanate-based polyimide foam(IBPIF),was fabricated by operable combination between different distinctive acoustic *** structure of IBPIF was facilely and obviously adjusted by increased slurry temperature corresponding to change in distinctive acoustic ***,density of all IBPIF kept at only 12-17 kg/*** increasing slurry temperature from 0℃to 40℃,cell size and window opening rate gradually increased from 553μm to 791μm and from 6.85%to 58.46%,*** this study,IBPIF generated by slurries at 0℃(marked as PIF-2)and 40℃(marked as PIF-6)showed best and distinctive acoustic behavior in 315-800 Hz and 800-6300 Hz regions,*** acoustic behavior study of combined IBPIF prepared by stitching combination between two distinctive acoustic IBPIFs,results showed that only when PIF-6 sheet used as sound receiving surface even though with thickness of only 10 mm could the combined IBPIF possess the best acoustic level in 800-6300 Hz region as ***,acoustic behavior in 315-800 Hz region could be significantly enhanced by increasing thickness of PIF-2 and could reach or close to the best acoustic level.

关键词： Isocyanate-based polyimide foam Slurry temperature Cellular structure Distinctive acoustic Combination style

Bearing-only Visual SLAM for Small Unmanned Aerial Vehicles in GPS-denied Environments

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International Journal of Automation and computing 2013年第5期10卷 387-396页

作者： chao-lei Wang Tian-Miao Wang Jian-Hong Liang Yi-Cheng Zhang Yi Zhou Robotics Institute Beijing University of Aeronautics and Astronautics

This paper presents a hierarchical simultaneous localization and mapping（SLAM） system for a small unmanned aerial vehicle（UAV） using the output of an inertial measurement unit（IMU） and the bearing-only observations from an onboard monocular camera.A homography based approach is used to calculate the motion of the vehicle in 6 degrees of freedom by image feature *** visual measurement is fused with the inertial outputs by an indirect extended Kalman filter（EKF） for attitude and velocity ***,another EKF is employed to estimate the position of the vehicle and the locations of the features in the *** simulations and experiments are carried out to test the performance of the proposed *** result of the comparison with the referential global positioning system/inertial navigation system（GPS/INS） navigation indicates that the proposed SLAM can provide reliable and stable state estimation for small UAVs in GPS-denied environments.

关键词： Visual simultaneous localization and mapping(SLAM) bearing-only observation inertial measurement unit small unmanned aerial vehicles(UAVs) GPS-denied environment

Low temperature synthesis of ITO nanoparticles with cubic structure by calcining a mixture of indium tin hydroxide and sodium chloride

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Rare Metals 2017年第7期36卷 607-611页

作者： Xing-Hua Su Ben-Pan Wang lei-chao Meng Peng Zhao Tao Ai Xin Yan School of Materials Science and Engineering Chang'anUniversityXi'an 710061China

The indium tin oxide （ITO） nanoparticles with cubic structure were synthesized by heating a mixture of indium tin hydroxide and sodium chloride at low temper- ature of 300 ℃ for 2 h and washing with water. The effects of sodium chloride addition on the ITO phase and mor- phology were investigated using differential scanning cal- orimetry （DSC）, thermogravimetric analysis （TGA）, X-ray diffraction （XRD）, and transmission electron microscopy （TEM）. It is found that sodium chloride addition helps the formation of cubic structure of ITO nanoparticles. The particle size of the resulted ITO powder is about 3 nm.

关键词： Keywords Synthesis Cubic structure ITO Nanoparticles Sodium chloride

Effects of UV-A exposures on longevity and reproduction in Helicoverpa armigera, and on the development of its F1 generation

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Insect Science 2011年第6期18卷 697-702页

作者： Chang-Yu Zhang Jian-Yu Meng Xiao-Ping Wang Fen Zhu chao-Liang lei Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory College of Plant Science and TechnologyHuazhong Agricultural University Wuhan China

Helicoverpa armigera adults display a conspicuous positive phototactic behavior to light stimuli, and are especially sensitive to ultraviolet （UV） light. The effects of UV-A （longwave） exposures on adult longevity and reproduction in H. armigera were investigated, as well as the development of the Ft generation. Paired adults were exposed to UV-A for various time periods （0, 1, 5 and 9 h/day）, until the end of adult life. The results showed that adult longevity decreased with increasing exposure time for both sexes, and a significant decrease was observed after exposure for 5 and 9 h/day. Fecundity increased when adults were exposed for 1 and 5 h/day, and a significant difference was observed in the 5 h/day group. Oviposition rates of females in all treatments were significantly higher than in the control. Exposure to UV-A for longer periods （5 and 9 h/day） caused a decline in cumulative survival of F1 immature stages, but no significant differences were found in egg hatch, pupation and eclosion. The developmental periods of F1 larvae were significantly prolonged after exposure to UV-A for 5 and 9 h/day. UV-A radiation had no significant effects on F1 pupal period.

关键词： development Helicoverpa armigera longevity oxidative stress,reproduction UV-A

Robust and flexible 3D integrated FeNi@NHCFs air electrode for high-performance rechargeable zinc-air battery

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Rare Metals 2024年第11期43卷 5677-5689页

作者： lei-chao Meng Hao Zhang Le Kang Yi Zhang Neng-Fei Yu Fan Zhang Hui-Ling Du Qinghai Provincial Key Laboratory of Nanomaterials and Technology Qinghai Minzu UniversityXi'ning 810007China College of Materials Science and Engineering Xi'an University of Science and TechnologyXi'an 710054China School of Energy Sciences and Engineering Nanjing Tech UniversityNanjing 211816China School of Materials Science and Engineering East China Jiaotong UniversityNanchang 330013China

Designing bifunctional oxygen reduction/evolution(ORR/OER)catalysts with high activity,robust stability and low cost is the key to accelerating the commercialization of rechargeable zinc-air battery(RZAB).Here,we propose a template-assisted electrospinning strategy to in situ fabricate 3D fibers consisting of FeNi nanoparticles embedded into N-doped hollow porous carbon nanospheres(FeNi@NHCFs)as the stable binder-free integrated air cathode in RZAB.3D interconnected conductive fiber networks provide fast electron transfer pathways and strengthen the mechanical ***,N-doped hollow porous carbon nanospheres not only evenly confine FeNi nanoparticles to provide sufficient catalytic active sites,but also endow optimum mass transfer environment to reduce diffusion *** RZABs assembled by FeNi@NHCFs as integrated air cathodes exhibit outstanding battery performance with high open-circuit voltage,large discharge specific capacity and power density,durable cyclic stability and great ***,this work brings a useful strategy to fabricate the integrated electrodes without using any polymeric binders for metal air batteries and other related fields.

关键词： Integrated electrode Oxygen reduction reaction Oxygen evolution reaction Rechargeable zinc-air battery

Secondary Hardening, Austenite Grain Coarsening and Surface Decarburization Phenomenon in Nb-Bearing Spring Steel

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Journal of Iron and Steel Research International 2012年第3期19卷 47-51,61页

作者： ZHANG chao-lei, LIU Ya-zheng, ZHOU Le-yu, JIANG chao (School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China) School of Materials Science and Engineering University of Science and Technology Beijing Beijing China

The secondary hardening, the austenite grain coarsening and the surface decarburization phenomenon of Nb-bearing spring steel were investigated, and the effects of niobium on tempered microstructure was studied using scanning electron microscope. The results show that the micro-addition of niobium increases the tempering resistance and produces secondary hardening. The effect of niobium on the size and distribution of cementite particles is one of the primary reasons to increase the hardness after tempering. The grain-coarsening temperature of the spring steel is raised 150 ~C due to Nb-addition. Furthermore, both the secondary hardening and the austenite grain coarsening phenomenon congruously demonstrate niobium begins observably dissolving above 1 100 ℃ in the spring steel. Be- sides, niobium microalloying is an effective and economy means to decrease the decarburization sensitivity of the spring steels.

关键词： spring steel! microalloyingl secondary hardening grain coarsening surface decarburization

Mitigating cadmium accumulation in rice without compromising growth via modifying the regulatory region of OsNRAMP5

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Stress Biology 2023年第1期3卷 369-376页

作者： Zhenling Luo chao-lei Liu Xiaofei Yang Jian-Kang Zhu chao-Feng Huang National Key Laboratory of Plant Molecular Genetics Shanghai Center for Plant Stress BiologyCenter for Excellence in Molecular Plant SciencesChinese Academy of SciencesShanghai 200032China University of the Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Rice Biology and Breeding China National Rice Research InstituteHangzhou 310006China Institute of Advanced Biotechnology and School of Life Sciences Southern University of Science and TechnologyShenzhen 518055China

Cadmium(Cd)intake poses a significant health risk to humans,and the contamination of rice grains with Cd is a major concern in regions where rice is a staple *** the knockout of OsNRAMP5,which encodes a key transporter responsible for Cd and manganese(Mn)uptake,can significantly reduce Cd accumulation in rice grains,recent studies have revealed that this knockout adversely affects plant growth,grain yield,and increases vulnerability to abiotic and biotic stresses due to reduced Mn *** this study,we employed CRISPR/Cas9 technology to modify the regulatory region of OsNRAMP5 with the aim of reducing Cd accumulation in rice *** findings demonstrate that mutations in the regulatory region of OsNRAMP5 do not impact its expression pattern but result in a reduction in *** decreased translation of OsNRAMP5 effectively decreases grain Cd accumulation while leaving Mn accumulation and important agronomic traits,including yield,***,our study presents a practical and viable strategy for reducing Cd accumulation in rice grains without compromising Mn accumulation or overall rice production.

关键词： Cadmium accumulation CRISPR/Cas9 OsNRAMP5 translation Oryza sativa(rice) Regulatory region

Effect of climate change on the trends of evaporation of phreatic water from bare soil in Huaibei Plain, China

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Journal of Groundwater Science and Engineering 2017年第3期5卷 213-221页

作者： SHANG Man-ting LIU Pei-gui lei chao LIU Ming-chao WU Liang Hefei University of Technology 230009 Heifei Province China

When the soil condition and depth to water table stay constant, climate condition will then be the only determinant of evaporation intensity of phreatic water from bare soil. Based on a series of long-term quality-controlled data collected at the Wudaogou Hydrological Experiment Station in the Huaibei Plain, Anhui, China, the variation trends of the evaporation rate of phreatic water from bare soil were studied through the Mann-Kendall trend test and the linear regression trend test, followed by the study on the responses of evaporation to climate change. Results indicated that in the Huaibei Plain during 1991-2008, evaporation of phreatic water from bare soil tended to increase at a rate of 5% on monthly scale in March, June and July while in other months the increase was minor. On the seasonal basis, the evaporation saw significant increase in spring and summer. In addition, annual evaporation tended to grow evidently over time. When air temperature rises by 1 °C, the annual evaporation rate increases by 7.24–14.21%, while when the vapor pressure deficit rises by 10%, it changes from-0.09 to 5.40%. The study also provides references for further understanding of the trends and responses of regional evapotranspiration to climate change.

关键词： Climate change Evaporation of phreatic water from bare soil Fluvo-aquic soil Huaibei Plain Lime concretion black soil

Cultural Introduction in English Vocabulary Teaching in China

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Sociology Study 2018年第4期8卷 180-187页

作者： chao lei Zhoukou Normal University China

Every language possesses three cardinal elements： phonetic element, lexical element, and grammatical structure, of which lexis is the fundamental pillar that supports the huge system of a language. The close relationship between language and culture is most readily seen in words. In fact, being the most active and elastic element of a language, vocabulary has the greatest culture-loading capacity. Vocabulary teaching is an integral part of foreign language teaching. Its efficiency has a direct relation with the development of the learners＇ communicative competence. Vocabulary is culture-bound, so it is self-evident that culture introduction is indispensable in teaching. The author attempts to make a comparison between English and Chinese cultures, to make clear how cultural disparities exist in English and Chinese vocabulary, and to put forward some constructive suggestions on how to integrate culture into vocabulary teaching in Chinese schools, so as to promote the efficiency of vocabulary teaching and improve learners＇ competence in intercultural communication.

关键词： Cultural differences English vocabulary teaching principles approaches

Life cycle of Chetoneura shennonggongensis （Diptera： Keroplatidae： Keroplatinae） from Jiangxi Province, China

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Insect Science 2009年第4期16卷 351-359页

作者： Xue-Zhen Li Chang-Ying Niu Qiu-Ying Huang chao-Liang lei David W. Stanley Key Laboratory of Utilization of Insect Resources and Sustainable Control of Pests Huazhong Agricultural University Wuhan China Agricultural Research Service Biological Control of Insects Research Laboratory Columbia USA

We report the first description of the biology of non-bioluminescent Keroplatidae from China. The life cycle of Chetoneura shennonggongensis is documented from laboratory culture and from field observations. The larval stage usually lasts 8-10 months. Large amounts of pupae are observed in late June, where they remain suspended horizontally or vertically from silk threads. The pupal suspending postures differ from other Keroplatidae species. Sexual differentiation is evident from the pupal stage. July is the peak time of adult emergence. Mating usually takes place immediately upon female emergence if adult males are available. The adult life span is short. Females live a maximum of 5 days and males 7 days. Egg development time varies from 20 30 days depending on environmental temperature. Larvae hang long sticky silk threads with a series of mucous droplets to capture prey. Some behaviors associated with snare construction and prey capture are also described.

关键词： Chetoneura shennonggongensis Chinese Keroplatidae life cycle