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Characteristic Mode Analysis for Thin Dielectric Sheets with Alternative Surface Integral Equation

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Chinese Journal of Electronics 2022年第6期31卷 1181-1188页

作者： JIA Chunlai HE Zi DING Dazhi GUAN Ling AI Xia LIU Jiaqi chen xuewen Department of Communication Engineering Nanjing University of Science and Technology Science and Technology on Electromagnetic Scattering Laboratory Beijing Institute of Environmental Features National Key Laboratory of Science and Technology on Test Physics and Numerical Mathematics School of Physics and Wuhan National Laboratory for Optoelectronics Huazhong University of Science and Technology

When the dielectric sheet is electrically thin in the normal direction, the conventional volume integral equation(VIE) can be approximately simplified to the surface one. On this basis, a novel surface integral equation-based formulation is presented for analyzing characteristic mode(CM) of thin dielectric sheets. The resultant CMs are expressed with tangential and normal components of electric volume currents, which are more intuitive than the conventional VIE-based one. Due to the application of volume equivalence principle, the proposed formulation is immune to non-physical modes. The CMs of typical thin dielectric bodies, including the dielectric substrate and radome, are analyzed to show that the proposed formulation is computationally efficient with encouraging accuracy.

关键词： normal components alternative surface integral equation thin dielectric sheets normal direction electric volume currents dielectric sheet radome radomes dielectric bodies surface integral equation-based formulation volume equivalence principle thin dielectric bodies tangential components nonphysical modes electromagnetic wave scattering conventional volume integral equation integral equations characteristic mode analysis dielectric substrate

Effects of Tillage Management on Infiltration and Preferential Flow in a Black Soil, Northeast China

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Chinese Geographical Science 2013年第3期23卷 312-320页

作者： FAN Ruqin ZHANG Xiaoping YANG Xueming LIANG Aizhen JIA Shuxia chen xuewen Northeast Institute of Geography and Agroecology Chinese Academy of Sciences University of Chinese Academy of Sciences Greenhouse and Processing Crops Research Centre Agriculture and Agri-Food Canada

The impacts of no-tillage （NT） and moldboard plough （MP） managements on infiltration rate and preferential flow were characterized using a combined technique of double-ring device and dye tracer on a black soil （Mollisols） in Northeast China. The ob- jective of this study is to evaluate how tillage practices enhance soil water infiltration and preferential flow in favor of soil erosion con- trol in the study area. The steady infiltration rates under NT management are 1.6 and 2.1 times as high as those under MP management in the 6th and 8th years of the tillage management in place, while the infiltrated water amounts under NT management are 1.4 and 2.0 times as high as those under MP management, respectively. The depth of methylene blue penetrated into NT soil increases from 43 cm in the 6th year to 57 cm in the 8th year, which are 16 cm and 19 em deeper than those in MP soil, respectively. The results of morphol- ogic image show that more biological macro-pores occur in NT soil than in MP soil. These macro-pores play a key role in enhancing preferential flow in NT soil, which in turn promotes water infiltration through preferential pathways in NT soil. The results are helpful to policy-making in popularizing NT and have the implications for tillage management in regard to soil erosion control in black soil region of China.

关键词： no-tillage moldboard plough dye tracer macro-pore black soil Northeast China

菊芋饲料的活性成分、营养价值及其在畜禽生产中的应用

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中国畜牧杂志 2025年第2期61卷 32-37页

作者：路顺萍陈雪文李龙龙吴启辉赵明鑫张苏江塔里木大学动物科学与技术学院

随着我国畜禽养殖规模快速扩大，现有的饲料资源已不能满足养殖需求。因此，开发产量大、营养价值高、价格低廉的非常规饲料对畜禽养殖至关重要。菊芋作为一种新型的饲料作物，具有抗寒、抗旱、耐盐碱、高产、一年多生等优点，并且富含... 详细信息

随着我国畜禽养殖规模快速扩大，现有的饲料资源已不能满足养殖需求。因此，开发产量大、营养价值高、价格低廉的非常规饲料对畜禽养殖至关重要。菊芋作为一种新型的饲料作物，具有抗寒、抗旱、耐盐碱、高产、一年多生等优点，并且富含多种氨基酸、维生素、矿物质，其块茎、茎叶以及加工生产的菊粉、菊芋粕均可作为饲料或添加剂进行饲喂。菊粉作为主要活性成分，具有增强免疫系统、调节肠道功能、降低血脂等功能。本文主要综述了菊芋饲料的活性成分、营养价值及在畜禽养殖业中的应用进展，以期为菊芋饲料在畜禽生产中的广泛应用及深入研究提供参考。

关键词：菊芋活性成分营养价值菊粉畜禽养殖

Dynamic gain driven mode-locking in GHz fiber laser

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Light(Science & Applications) 2024年第11期13卷 2715-2725页

作者： xuewen chen Wei Lin Xu Hu Wenlong Wang Zhaoheng Liang Lin Ling Yang Yang Yuankai Guo Tao Liu Dongdan chen Xiaoming Wei Zhongmin Yang School of Physics and Optoelectronics State Key Laboratory of Luminescent Materials and DevicesGuangdong Engineering Technology Research and Development Center of Special Optical Fiber Materials and DevicesGuangdong Provincial Key Laboratory of Fiber Laser Materials and Applied TechniquesSouth China University of TechnologyGuangzhouChina Research Institute of Future Technology South China Normal UniversityGuangzhouGuangdongChina

Ultrafast lasers have become powerful tools in various fields,and increasing their fundamental repetition rates to the gigahertz(GHz)level holds great potential for frontier scientific and industrial *** various schemes,passive mode-locking in ultrashort-cavity fiber laser is promising for generating GHz ultrashort pulses(typically solitons),for its simplicity and ***,its pulse energy is far lower than the critical value of the existing theory,leading to open questions on the mode-locking mechanism of GHz fiber ***,we study the passive mode-locking in GHz fiber lasers by exploring dynamic gain depletion and recovery(GDR)effect,and establish a theoretical model for comprehensively understanding its low-threshold mode-locking mechanism with multi-GHz fundamental repetition ***,the GDR effect yields an effective interaction force and thereby binds multi-GHz solitons to form a counterpart of soliton *** is found that the resulting collective behavior of the solitons effectively reduces the saturation energy of the gain fiber and permits orders of magnitude lower pulse energy for continuous-wave mode-locking(CWML).A new concept of quasi-single soliton defined in a strongly correlated length is also proposed to gain insight into the dynamics of soliton assembling,which enables the crossover from the present mode-locking theory to the existing ***,two distinguishing dynamics of Q-switched mode-locking that respectively exhibit rectangular-and Gaussian-shape envelopes are theoretically indicated and experimentally verified in the mode-locked GHz fiber laser through the measurements using both the standard real-time oscilloscope and emerging time-lens *** on the proposed criterion of CWML,we finally implement a GDR-mediated mode-locked fiber laser with an unprecedentedly high fundamental repetition rate of up to 21 GHz and a signal-tonoise ratio of 85.9 dB.

关键词： fiber mode locking

Residue Return Effects Outweigh Tillage Effects on Soil Microbial Communities and Functional Genes in Black Soil Region of Northeast China

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Chinese Geographical Science 2023年第4期33卷 679-692页

作者： WANG Qian JIA Shuxia LIANG Aizhen chen xuewen ZHANG Shixiu ZHANG Yan Neil B MCLAUGHLIN GAO Yan HUANG Dandan Key Laboratory of Mollisols Agroecology Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun 130102China School of Geography Sciences Nanjing Normal UniversityNanjing 210023China College of Forestry Beihua UniversityJilin 132013China University of Chinese Academy of Sciences Bejing 100049China Ottawa Research and Development Centre Agriculture and Agri-Food CanadaOttawa K1A 0C6Canada

Conservation tillage as an effective alternative to mitigate soil degradation has attracted worldwide attention,but the influences of conservation tillage on soil microbial community and especially function remain *** metagenomics sequencing was performed to examine the taxonomic and functional community variations of black soils under three tillage regimes,namely no-tillage with residue(maize straw)return(NTS),moldboard plow with residue return(MPS),and moldboard plow without residue return(MPN)in Northeast *** results revealed:1)Soil bacterial and archaeal communities differed significantly under different tillage regimes in contrast to soil fungal community.2)The overlay of less tillage and residues return under NTS led to unique soil microbial community composition and functional ***,in contrast to other treatments,NTS increased the relative abundances of some taxa such as Bradyrhizobium,Candidatus Solibacter,and Reyranella,along with the relative abundances of some taxa such as Sphingomonas,Unclassified Chloroflexi and Nitrososphaera decreased;NTS had a unique advantage of increasing the relative abundances of genes involved in‘ATP-binding cassette(ABC)transporters’and‘quorum sensing(QS)’pathways,while MPN favored the genes involved in‘flagellar assembly’pathway and some metabolic pathways such as‘carbon’and‘glyoxylate and dicarboxylate’and‘selenocompound’metabolisms.3)Significantly different soil bacterial phyla(Acidobacteria,Gemmatimonadetes,and Chloroflexi)and metabolic pathways existed between MPN and another two treatments(NTS and MPS),while did not exist between NTS and MPS.4)Dissolved organic carbon(DOC)and soil bulk density were significantly affected(P<0.05)by tillage and accounted for the variance both in microbial(bacterial)community structure and functional *** results indicated that a change in tillage regime from conventional to conservation tillage results in a shift of microbial community and

关键词： no-tillage microbial community composition Kyoto Encyclopedia of Genes and Genomes(KEGG)pathways soil properties

Wall Thinning Characteristics of Ti-3Al-2.5V Tube in Numerical Control Bending Process

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Journal of Shanghai Jiaotong university(Science) 2019年第5期24卷 647-653页

作者： HUANG Tao WANG Kun ZHAN Mei GUO Junqing chen xuewen chen Fuxiao SONG Kexing School of Materials Science and Engineering Henan University of Science and TechnologyLuoyang471023HenanChina Collaborative Innovation Center of Nonferrous Metals of Henan Province Luoyang471023HenanChina State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwesternPolytechnical UniversityXi'an710072China

A finite element(FE) model for the numerical control(NC) bending of Ti-3 Al-2.5 V titanium alloy seamless tube is established, considering the variation in the contractile strain ratio(CSR) and elastic modulus(E). The wall thinning characteristics of Ti-3 Al-2.5 V tube under different geometric and process conditions were investigated. The results showed that the CSR-E variation can change the wall thickness, but has no remarkable effect on the change characteristics. The reasonable parameter ranges are as follows: a bending-radius range not less than 1.5 times the outer diameter, a bend angle up to 180?, and a mandrel extension of 0-3 mm. The friction coefficient between the pressure die and the tube should be in the range of 0.20-0.35, and between the bending die and the tube should be in the range of 0.05-0.15. As long as the performance meets the requirements, the relative push-assistant speed should be as small as possible.

关键词： titanium alloy tube numerical control bending wall thinning contractile strain ratio elastic modulus

Design, Synthesis, Antifungal Activities and SARs of （R）-2-Aryl-4,5-dihydrothiazole-4-carboxylic Acid Derivatives

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Chinese Journal of Chemistry 2015年第11期33卷 1269-1275页

作者： Jingbo Liu Yuxin Li Youwei chen xuewen Hua Yingying Wan Wei Wei Haibin Song Shujing Yu Xiao Zhang Zhengming Li State Key Laboratory of Elemento-Organic Chemistry Collaborative Innovation Center of Chemical Science DQG Engineering ( Tianjin) Nankai University Tianjin 300071 China

Based on the structure of natural product 2-aryl-4,5-dihydrothiazole-4-carboxylic acid, a series of novel （R）-2-aryl-4,5-dihydrothiazole-4-carboxylic acid derivatives were designed and synthesized. Their structures were characterized by ^1H NMR, ^13C NMR and HRMS. The single crystal structure of compound 9b was determined by X-ray diffraction analysis. The antifungal activities were evaluated for the first time. The bioassay results indicated that most compounds exhibited moderate to good antifungal activities. The antifungal activities of compound 13a （against Cercospora arachidicola Hori）, 13d （against Alternaria solani）, and 16e （against Cercospora arachidieola Hori） were 61.9%, 67.3% and 61.9%, respectively, which are higher than those of the commercial fungicides chlorothalonil and carbendazim. Moreover, compound 13d exhibited excellent antifungal activities against 7 kinds of the fungi tested （66.7%, 77.3%, 63.0%, 87.9%, 70.0%, 70.0% and 80.0% at 50 μg/mL）. Therefore, 13d can be used as a new lead structure for the development of antifungal agents.

关键词： (R)-2-aryl-4,5-dihydrothiazole-4-carboxylic acid synthesis antifungal activity structure-activity relationship

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《离骚》创作时地新探

武汉大学学报（人文科学版） 2008年第1期61卷 12-19页

作者：陈学文湘南学院中文系

现当代楚辞学界对《离骚》的创作时地仍然有许多不同看法。根据对汉代学者的有关记载和对《离骚》及其它可靠屈原作品的仔细、全面的解读与分析,《离骚》最有可能是在约楚怀王(公元前313年)至怀王十八年(公元前311年)间被绌或待放于汉... 详细信息

现当代楚辞学界对《离骚》的创作时地仍然有许多不同看法。根据对汉代学者的有关记载和对《离骚》及其它可靠屈原作品的仔细、全面的解读与分析,《离骚》最有可能是在约楚怀王(公元前313年)至怀王十八年(公元前311年)间被绌或待放于汉北时所作,是屈原流传下来的最重要和最早的作品。

关键词：屈原离骚创作时地

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明初户帖制度的建立和户帖格式

中国经济史研究 2005年第4期 107-111页

作者：陈学文浙江省社会科学院历史所 310025

明初为了稳定社会秩序,克服财政危机,首先要建立户籍管理制度,为国家征收赋役提供基本依据,于洪武三年正式颁行户帖。洪武十四年在户帖制基础上推出了黄册,取代了户帖,成为有明一代完备的户籍管理制度。明初的户帖实物存世不多,作者经... 详细信息

明初为了稳定社会秩序,克服财政危机,首先要建立户籍管理制度,为国家征收赋役提供基本依据,于洪武三年正式颁行户帖。洪武十四年在户帖制基础上推出了黄册,取代了户帖,成为有明一代完备的户籍管理制度。明初的户帖实物存世不多,作者经过不断搜集,通过对三四件户帖实物的考释,基本弄清了其格式、内容及一些相关问题。

关键词：明代初期户帖格式