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Soil mineral nitrogen and yield-scaled soil N2O emissions lowered by reducing nitrogen application and intercropping with soybean for sweet maize production in southern China

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Journal of Integrative Agriculture 2017年第11期16卷 2586-2596页

作者： TANG Yi-ling YU Ling-ling guan ao-mei ZHOU Xian-yu WANG Zhi-guo GOU Yong-gang WANG Jian-wu Institute of Tropical and Subtropical Ecology~Key Laboratory of Agro-environment in the Tropics Ministry of Agriculture/KeyLaboratory of Agroecology and Rural Environment of Guangdong Regular Higher Education Institutions South China AgriculturalUniversity Guangzhou 510642 P.R. China

The increasing demand for fresh sweet maize （Zea mays L. saccharata） in southern China has prioritized the need to find solutions to the environmental pollution caused by its continuous production and high inputs of chemical nitrogen fertilizers. A promising method for improving crop production and environmental conditions is to intercrop sweet maize with legumes. Here, a three-year field experiment was conducted to assess the influence of four different cropping systems （sole sweet maize （SS）, sole soybean （SB）, two rows sweet maize-three rows soybean （S2B3） intercropping, and two rows sweet maize-four rows soybean （S2B4） intercropping）, together with two rates of N fertilizer application （300 and 360 kg N ha-1） on grain yield, residual soil mineral N, and soil N2O emissions in southern China. Results showed that in most case, inter- cropping achieved yield advantages （total land equivalent ratio （TLER=0.87-1.25） was above one）. Moreover, intercropping resulted in 39.8% less soil mineral N than SS at the time of crop harvest, averaged over six seasons （spring and autumn in each of the three years of the field experiment）. Generally, intercropping and reduced-N application （300 kg N ha-1） produced lower cumulative soil N20 and yield-scaled soil N20 emissions than SS and conventionaI-N application （360 kg N ha-l）, respectively. $2B4 intercropping with reduced-N rate （300 kg N ha-~） showed the lowest cumulative soil N20 （mean value=0.61 kg ha-1） and yield-scaled soil N20 （mean value=0.04 kg t-1） emissions. Overall, intercropping with reduced-N rate maintained sweet maize production, while also reducing environmental impacts. The system of S2B4 intercropping with reduced-N rate may be the most sustainable and environmentally friendly cropping system.

关键词： sweet maize-soybean intercrop cropping system N fertilizer rate grain yield soil mineral N soil NzO emissions

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减量施氮与大豆间作对蔗田氮平衡的影响

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应用生态学报 2015年第3期26卷 817-825页

作者：刘宇章莹杨文亭李志贤管奥湄王建武华南农业大学热带亚热带生态研究所广州510642 农业部华南热带农业环境重点实验室广州510642 华南农业大学广东省高等学校农业生态与农村环境重点实验室广州510642

通过2010—2013年的大田试验,探讨了2个施氮水平（300和525 kg·hm^-2）和3种种植模式（甘蔗、大豆单作及甘蔗-大豆1∶2间作）对蔗田大豆固氮、甘蔗和大豆氮素累积及氨挥发和氮淋溶的影响.结果表明：与大豆单作相比,甘蔗-大豆间作的大... 详细信息

通过2010—2013年的大田试验,探讨了2个施氮水平（300和525 kg·hm^-2）和3种种植模式（甘蔗、大豆单作及甘蔗-大豆1∶2间作）对蔗田大豆固氮、甘蔗和大豆氮素累积及氨挥发和氮淋溶的影响.结果表明：与大豆单作相比,甘蔗-大豆间作的大豆固氮效率下降,但不同施氮水平间作模式之间无显著差异.不同施氮水平和种植模式对甘蔗、大豆氮素累积无显著影响.减量施氮水平下氨挥发量低于常规施氮处理,不同施氮水平和种植模式对氮淋溶量无显著影响.除2011年甘蔗单作减量施氮水平下出现蔗田氮素亏缺（-66.22 kg·hm^-2）外,其余不同年份不同种植模式下氮素都处于盈余状态（73.10-400.03 kg·hm^-2）,施氮水平显著影响了蔗田的氮素盈亏,且常规施氮水平下氮素盈余量显著高于减量施氮处理,过高的氮素盈余增加了氮素污染农田环境的风险.从培肥地力、降低氮素污染环境的风险和节约生产成本等方面考虑,减量施氮水平下甘蔗-大豆间作模式具有一定的生态合理性.

关键词：甘蔗-大豆间作减量施氮氮平衡氨挥发氮淋溶

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Condensation behavior of gaseous phase during transported in the near-substrate boundary layer of plasma spray-physical vapor deposition

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Journal of Materials Science & Technology 2021年第8期67卷 127-134页

作者： mei-Jun Liu guan-Jun Yang State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and EngineeringXi'an fiaotong UniversityXi’anShaanxi710049PR China

Plasma spray-physical vapor deposition(PS-PVD)has exhibited the potential ability to prepare columnar structures for advanced thermal barrier coatings(TBCs).The coating structure is nominally affected by operating parameters,but it is controlled by the type of deposition unit actually and *** order to realize the columnar structure deposited by gaseous phase units,the transition behavior of gaseous phase units to clusters must be fundamentally *** work investigated the transport process of gaseous phase units in the PS-PVD near-substrate boundary layer along with the condensation *** Monte Carlo method was used to examine the transport process and condensation behavior of gaseous phase units under different scale boundary *** results show that it is easier to form more numerous larger clusters at the edge of the plasma jet than at the *** on the understanding of the changes in deposition unit caused by the condensation of gaseous phase in the near-substrate boundary layer of PS-PVD,an outlook towards TBCs with different structures is *** it is in good agreement with the experimental data.

关键词： Condensation behavior Transport process Cluster Boundary layer PS-PVD

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Rapid-developing Mg-based biodegradable materials:The editorial of the special issue on Mg-based functional materials-biomaterials section

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Journal of Magnesium and Alloys 2021年第6期9卷 2226-2228页

作者： Di mei Shaokang guan School of Materials Science and Engineering&Henan Key Laboratory of Advanced Magnesium Alloy Zhengzhou UniversityZhengzhou 450001HenanChina

Since physician Edward *** firstly tried to stop bleeding blood vessels with Mg wires in 1878[1],the history of Mg and its alloys as biomaterials has gone through more than 140 ***,in the latest 20 years,scientists from all over the world have carried out all-around research on Mg-based materials for the applications of vascular stents.

关键词： biomaterials bleeding alloys

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Three Types of Expression in Dark-Soliton Perturbation Theory Based on Squared Jost Solutions

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Communications in Theoretical Physics 2007年第1期47卷 15-18页

作者： ao Sheng-mei YAN Jia-Ren College of Physics and Information Science Hunan Normal University Changsha 410081 China

Three types of expression in the dark-soliton perturbation theory based on squared Jost solutions are invesgigaged in ghis paper. It is shown that there are three formally different results about the effects of perturbagion on a dark soliton, and it is proved by means of a transformation between two integral variables that they are essentially equivalent.

关键词： dark soliton perturbation theory squared Jost solution soliton velocity first-order correction

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The Dynamics of a Bright-Bright Vector Soliton in Bose-Einstein Condensation

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Chinese Physics Letters 2012年第5期29卷 18-21页

作者： AN Jia-Ren ZHOU Jie ao Sheng-mei Department of Physics Hunan Normal UniversityChangsha 410081

The dynamics of a bright-bright vector soliton in cigar-shaped Bose-Einstein condensate trapping in a harmonic potential is *** interaction between bright solitons in different species with small separation is *** the interaction between solitons of the same species,it is independent of the phase difference between the solitons,and may be of attraction or *** the former case,each soliton will oscillate about and pass through each other around the mass center of the system,which will also oscillate harmonically due to harmonic trapping potential.

关键词： harmonic soliton Einstein

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Pairing effects on the fragment mass distribution of Th,U,Pu,and Cm isotopes

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Nuclear Science and Techniques 2023年第11期34卷 128-139页

作者： Xin guan Jin‑Huan Zheng mei‑Yan Zheng Department of Physics Liaoning Normal UniversityDalian 116029China

In this article,a comprehensive study of the fission process of Th,U,Pu,and Cm isotopes using a Yukawa-folded meanfield plus standard pairing model is *** study focused on analyzing the effects of the pairing interaction on the fragment mass distribution and its dependence on nuclear *** significant role of pairing interactions in the fragment mass distributions of^(230)Th,^(234)U,^(240)Pu,and^(246)Cm was *** analysis revealed that increasing the pairing interaction strength decreased the asymmetric fragment mass distribution and increased the symmetric ***,the odd-even mass differences at symmetric and asymmetric fission points were examined,highlighting their sensitivity to changes in the pairing interaction *** analysis of the Th,U,Pu,and Cm isotope fragment mass distributions demonstrated the effectiveness of the model in reproducing the experimental *** addition,the effects of the zero-point energy and half-width parameter on the fragment mass distribution for^(240)Pu were ***,this study provides valuable insights into the fission process by emphasizing the importance of pairing interactions and their relationship with nuclear elongation.

关键词： Nuclear fission Pairing interaction Fragment mass distribution Actinide nuclei

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Embeddings of weighted Sobolev spaces and degenerate elliptic problems

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Science China Mathematics 2017年第8期60卷 1399-1418页

作者： GUO ZongMing mei LinFeng WAN FangShu guan XiaoHong Department of Mathematics Henan Normal University

New embeddings of some weighted Sobolev spaces with weights a(x)and b(x)are *** weights a(x)and b(x)can be *** applications of these embeddings to a class of degenerate elliptic problems of the form-div(a(x)?u)=b(x)f(x,u)in?,u=0 on??,where?is a bounded or unbounded domain in RN,N 2,are *** main results of this paper also give some generalizations of the well-known Caffarelli-Kohn-Nirenberg inequality.

关键词： positive weak solutions Sobolev type embeddings weighted elliptic equations Caffarelli-Kohn- Nirenberg inequality

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Supertough spontaneously self-healing polymer based on septuple dynamic bonds integrated in one chemical group

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Science China Chemistry 2022年第2期65卷 363-372页

作者： Luzhi Zhang Qingbao guan ao Shen Rasoul Esmaeely Neisiany Zhengwei You meifang Zhu State Key Laboratory for Modification of Chemical Fibers and Polymer Materials Shanghai Belt and Road Joint Laboratory of Advanced Fiber and Low-dimension Materials(Donghua University)College of Materials Science and EngineeringShanghai Engineering Research Center of Nano-Biomaterials and Regenerative MedicineInstitute of Functional MaterialsDonghua UniversityResearch Base of Textile Materials for Flexible Electronics and Biomedical ApplicationsChina Textile Engineering SocietyShanghai 201620China Department of Materials and Polymer Engineering Hakim Sabzevari UniversitySabzevar ***Iran

The development of spontaneously self-healing materials with excellent mechanical properties remains a formidable challenge despite the extensive interest in such *** is because the self-healing and mechanical properties of a material are usually optimized via contradictory *** present study demonstrated a supertough spontaneously self-healing polymer,Fe-(2,6-diacetylpyridine dioxime)-urethane-based polyurethane(Fe-PPOU)based on septuple dynamic bonds integrated in one chemical group.A synergistic effect was induced by the presence of multiple dynamic crosslinking points,which comprised the integrated dynamic interactions,and the hidden lengths of the folded polymeric chains in ***,the mechanical and self-healing properties of the polymer were simultaneously ***-PPOU demonstrated the highest reported toughness(139.8 MJ m^(-3))among all the room-temperature spontaneously self-healing polymers with a nearly 100%healing ***-PPOU exhibited instant(30 s)self-healing to reach a strength of 1.6 MPa that was higher than the original strength of numerous recently reported self-healing polymers.

关键词： oxime-urethane bonds hydrogen bonds metal-coordination bonds 2 6-diacetylpyridine dioxime self-healing

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Analysis of volatile compounds in Herba Asari by single-drop micro-extraction gas chromatography mass spectrometry

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Chinese Chemical Letters 2013年第6期24卷 542-544页

作者： guan-Jie Wang mei-Ling Qi National Institutes for Food and Drug Control School of Chemistry Beijing Institute of Technology

A rapid headspace single-drop micro-extraction（mix） gas chromatography mass spectrometry（SDMEGC -MS） for the analysis of the volatile compounds in Herba Asari was developed in this study.A mixed solvent of n-tridecane and butyl acetate（1：1） was finally used for the extraction at 70 C for 15 min with sample amount of 0.750 g and 100 mesh particle *** the determined conditions,the pound samples of Herba Asari were directly applied for the ***-GC-MS,SPME-GC-MS and SD-GCMS methods were compared and the results showed that SDME-GC-MS method was a simple, inexpensive and effective way to measure the volatile compounds in Herba Asari and could be used for the analysis of volatile compounds in complex samples.

关键词： Single-drop micro-extraction Herba Asari Volatile compounds Traditional Chinese medicine

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