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Journal of Integrative Agriculture 2022年第3期21卷 597-609页

作者： FENG Lu chi Bao-jie DONG He-zhong Zhengzhou Research Base State Key Laboratory of Cotton Biology School of Agricultural Sciences Zhengzhou University Cotton Research Center Shandong Academy of Agricultural Sciences College of Agricultural Science and Technology Shandong Agriculture and Engineering University

Since the founding of the People’s Republic of china in 1949,significant achievements have been made in cotton production in *** has maintained its position as the world’s largest cotton producer for 33 years(1983–2015),with average annual increases of 3.5 and 3.9% in the unit yield and total output of cotton,*** production has played an extremely important role in the development of the national economy and the improvement of living *** the cotton planting area has been reduced in recent years,the total output has remained relatively unchanged due to the continuous increase in the unit ***’s dominant position in global cotton production is undoubtedly attributed to the progress and development of cotton cultivation *** the past 70 years,china has established a high-yielding and high-efficiency cotton cultivation mode that corresponds to its national conditions,including a large population and a limited land ***,cotton cultivation technology is constantly being innovated and developed to keep pace with the *** this paper,we review the development of cotton production and cultivation in china over the past 70 years,with a particular focus on the innovation and development of cotton cultivation technology with chinese *** review is intended to provide guidance for the sustainable development of china’s cotton production in the future and to provide a reference for global cotton production.

关键词： china cotton cultivation technology outlook

Control of cotton pests and diseases by intercropping:A review

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Journal of Integrative Agriculture 2021年第12期20卷 3089-3100页

作者： chi Bao-jie ZHANG Dong-mei DONG He-zhong Cotton Research Center Shandong Academy of Agricultural SciencesJinan 250100P.R.China College of Life Sciences Shandong Normal UniversityJinan 250014P.R.China College of Agronomy Hebei Agricultural UniversityBaoding 071000P.R.China

Cotton(Gossypium hirsutum L.)is a globally important crop that is often damaged by pests and *** cotton pests and diseases management is dependent on chemical *** chemical pesticides are usually effective,long-term application of these pesticides often leads to increased insecticide resistance in the pests,fewer natural enemies,reduced natural control,and a degraded *** of increased environmental awareness and the need for sustainable cotton production,the control of cotton pests and diseases using biological means like intercropping is increasingly receiving *** of cotton with other crops can often boost the total yield and output of the intercropping system and provide significant economic benefits without sacrificing cotton *** also increases the number of natural enemies,and reduces the occurrence of cotton pests and diseases by altering the ecological structure and environmental conditions in the ***-based intercropping is an effective strategy to reduce the competition between cotton and grain or other economic crops for arable *** is also an important way to increase the populations of natural enemies in cotton fields for the management of pests and ***,inappropriate intercropping can also increase labor requirements and even result in inadequate control of pests and *** review focuses on the performance and the mechanisms of intercropping for reducing cotton pests and disease as well as on the effective management of intercropping *** risks and limitations,as well as the study approaches needed and the prospects of intercropping for the control of cotton pests and diseases,are also *** information is intended to aid researchers and growers in designing economically viable and ecologically friendly pest and disease management strategies that will reduce the use of chemicals and the cost of cotton production.

关键词： cotton-based intercropping pest management risk and limitation

A New Method of Identifying 3D Null Points in Solar Vector Magnetic Fields

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chinese Journal of Astronomy and Astrophysics 2005年第5期5卷 443-447页

作者： Hui Zhao Jing-Xiu Wang Jun Zhang chi-jie Xiao National Astronomical Observatories Chinese Academy of Sciences Beijing 100012

Employing the Poincar6 index of isolated null-points in a vector field, we worked out a mathematical method of searching for 3D null-points in coronal magnetic fields. After introducing the relevant differential topology, we test the method by using the analytical model of Brown ＆ Priest. The location of nullpoint identified by our method coincides precisely with the analytical solution. Finally we apply the method to the 3D coronal magnetic fields reconstructed from an observed MDI magnetogram of a super-active region （NOAA 10488）. We find that the 3D null-point seems to be a key element in the magnetic topology associated with flare occurrence.

关键词： Sun: flares - Sun: corona- Sun: magnetic fields

A novel numerical simulation of CO_(2) immiscible flooding coupled with viscosity and starting pressure gradient modeling in ultra-low permeability reservoir

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Frontiers of Earth Science 2023年第3期17卷 884-898页

作者： jie chi Binshan JU Jiabei WANG Xing ZHANG Wenbin CHEN Mengfei ZHANG School of Big Data and Fundamental Sciences Shandong Institute of Petroleum and Chemical TechnologyDongying 257061China School of Energy Resources China University of Geosciences(Beijing)Beijing 100083China Key Laboratory of Geological Evaluation and Development Engineering of Unconventional Natural Gas Energy Beijing 100083China School of Petroleum Engineering Chongqing University of Science&TechnologyChongqing 401331China Research Institute of Petroleum Engineering Technology Shengli Oilfield CompanySINOPECDongying 257000China

CO_(2) immiscible flooding is an environmentally-friendly and effective method to enhance oil recovery in ultra-low permeability reservoirs.A mathematical model of CO_(2) immiscible flooding was developed,considering the variation in crude oil viscosity and starting pressure gradient in ultra-low permeability reservoirs based on the non-Darcy percolation *** mathematical model and numerical simulator were developed in the C++language to simulate the effects of fluid viscosity,starting pressure gradient,and other physical parameters on the distribution of the oil pressure field,oil saturation field,gas saturation field,oil viscosity field,and oil *** results showed that the formation pressure and pressure propagation velocity in CO_(2) immiscible flooding were lower than the findings without considering the starting pressure *** formation oil content saturation and the crude oil formation viscosity were higher after the consideration of the starting pressure *** viscosity of crude oil considering the initiation pressure gradient during the formation was higher than that without this gradient,but the yield was lower than that *** novel mathematical models helped the characterization of seepage resistance,revealed the influence of fluid property changes on seepage,improved the mathematical model of oil seepage in immiscible flooding processes,and guided the improvement of crude oil recovery in immiscible flooding processes.

关键词： viscosity starting pressure gradient flow simulation CO_(2)immiscible flooding ultra-low permeability reservoir

Determination of the Topology Skeleton of Magnetic Fields in a Solar Active Region

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chinese Journal of Astronomy and Astrophysics 2008年第2期8卷 133-145页

作者： Hui Zhao Jing-Xiu Wang Jun Zhang chi-jie Xiao Hai-Min Wang National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 Big Bear Solar Observatory 40386 North Shore Lane Big Bear City CA 92314 USA

Magnetic topology has been a key to the understanding of magnetic energy release mechanism. Based on observed vector magnetograms, we have determined the threedimensional （3D） topology skeleton of the magnetic fields in the active region NOAA 10720. The skeleton consists of six 3D magnetic nulls and a network of corresponding spines, fans, and null-null lines. For the first time, we have identified a spiral magnetic null in Sun＇s corona. The magnetic lines of force twisted around the spine of the null, forming a ＇magnetic wreath＇ with excess of free magnetic energy and resembling observed brightening structures at extraultraviolet （EUV） wavebands. We found clear evidence of topology eruptions which are referred to as catastrophic changes of topology skeleton associated with a coronal mass ejection （CME） and an explosive X-ray flare. These results shed new lights on the structural complexity and its role in explosive magnetic activity. The concept of flux rope has been widely used in modelling explosive magnetic activity, although their observational identity is rather obscure or, at least, lacking of necessary details up to date. We suggest that the magnetic wreath associated with the 3D spiral null is likely an important class of the physical entity of flux ropes.

关键词： Sun: magnetic fields -- Sun: solar corona -- Sun: activity

Large-Mode-Area Double-Cladding Photonic Crystal Fiber Laser in the Watt Range at 980nm

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chinese Physics Letters 2011年第8期28卷 119-121页

作者： LI Ping-Xue ZHANG Xue-Xia LIU Zhi chi Jun-jie Institute of Laser Engineering Beijing University of TechnologyBeijing 100124

We report on a quasi-three-level large-mode-area double-clad Yb-doped fiber laser that adopts a linear cavity consisting of a 0°fiber end and a cavity *** kinds of Yb−doped photonic crystal fiber(PCF)with different inner-clads(170µm and 200µm)and absorption coefficients(4.5 dB/m and 3 dB/m)are used as the gain *** optimizing the structure and elements of the cavity,maximum output powers of 1.24 W and 1.1 W were yielded with optical conversion efficiencies of 7.8%and 6.8%when the fiber lengths were 25 cm and 40 cm with 170µm and 200µm inner-claddings,respectively.

关键词： fiber Crystal cavity

Influence of bifurcation position and length of side chains on the structure of isoindigo-based conjugated polymer thin films

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chinese Chemical Letters 2017年第2期28卷 333-337页

作者： Shuai-jie chi Liang Chen Jian-Gang Liu Xin-Hong Yu Yan-Chun Han State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China University of the chinese Academy of Sciences Beijing 100049 China

We chose a series of isoindigo-based conjugated polymer（ⅡDDT,ⅡDDT-C3 and ⅡDDT-C4） with different length of side chains and bifurcation positions to investigate the relationship between the degree of alignment and the length of side chains and bifurcation *** found that the dichroic ratio was increased from 2.37 to 5.23 when the side chain was longer and the bifurcation position was away from the *** π-π stacking distance was decreased from 3.67 A to 3.61 A when the bifurcation position was away from the backbone because of its smaller hindrance and the d-spacing of the（100）was increased from 20.06 A to 25.21 A when the side chain was *** the polymers were adopted an edge-on orientation with the backbone paralleled with the long axis of *** weak interaction of side-chain in ⅡDDT-C4 was beneficial for the molecules being rearranged in parallel during the contact line receding and the strong n-n interaction could accelerate the interchain assembly of the parallel molecules through π-π interaction to form aligned fibers.

关键词： Isoindigo-based conjugated polymers Alignment The length of side chains Bifurcation positions π-π interaction

Laboratory simulation of CO_(2) immiscible gas flooding and characterization of seepage resistance

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Frontiers of Earth Science 2023年第3期17卷 797-817页

作者： jie chi Binshan JU Wenbin CHEN Mengfei ZHANG Rui ZHANG Anqi MIAO Dayan WANG Fengyun CUI School of Big Data and Fundamental Sciences Shandong Institute of Petroleum and Chemical TechnologyDongying 257061China School of Energy Resources China University of Geosciences(Beijing)Beijing 100083China Key Laboratory of Geological Evaluation and Development Engineering of Unconventional Natural Gas Energy Beijing 100083China School of Chemical Engineering Shandong Institute of Petroleum and Chemical TechnologyDongying 257061China

CO_(2) flooding can significantly improve the recovery rate, effectively recover crude oil, and has the advantages of energy saving and emission reduction. At present, most domestic researches on CO_(2) flooding seepage experiments are field tests in actual reservoirs or simulations with reservoir numerical simulators. Although targeted, the promotion is poor. For the characterization of seepage resistance, there are few studies on the variation law of seepage resistance caused by the combined action in the reservoir. To solve this problem, based on the mechanism of CO_(2), a physical simulation experiment device for CO_(2) non-miscible flooding production manner is designed. The device adopts two displacement schemes, gas-displacing water and gas-displacing oil, it mainly studies the immiscible gas flooding mechanism and oil displacement characteristics based on factors such as formation dip angle, gas injection position, and gas injection rate. It can provide a more accurate development simulation for the actual field application. By studying the variation law of crude oil viscosity and start-up pressure gradient, the characterization method of seepage resistance gradient affected by these two factors in the seepage process is proposed. The field test is carried out for the natural core of the S oilfield, and the seepage resistance is described more accurately. The results show that the advancing front of the gas drive is an arc, and the advancing speed of the gas drive oil front is slower than that of gas drive water;the greater the dip angle, the higher the displacement efficiency;the higher the gas injection rate is, the higher the early recovery rate is, and the lower the later recovery rate is;oil displacement efficiency is lower than water displacement efficiency;taking the actual core of S oilfield as an example, the mathematical representation method of core start-up pressure gradient in low permeability reservoir is established.

关键词： laboratory_simulation viscosity starting pressure gradient CO immiscible flooding characterization of seepage resistance

Phytoremediation of PAH-Contaminated Sediments by Potamogeton Crispus L. with Four Plant Densities

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Transactions of Tianjin University 2015年第5期21卷 440-445页

作者：孟凡波迟杰 School of Environmental Science and Engineering Tianjin University

In order to investigate the effect of plant density ofPotamogeton crispus L. on the remediation of sedi- ments contaminated by polycyclic aromatic hydrocarbons, a 54-day experiment with four plant densities （642, 1 604, 2 567 and 3 530 plants/m^2） was conducted. The results showed higher plant density with slower plant growth rate. Surface area per plant was the most sensitive root parameter to plant density. At the end of the 54-day experi- ment, planting P. crispus enhanced the dissipation ratios of phenanthrene and pyrene in sediments by 6.5%-26,2% and 0.95%-13.6%, respectively. The dissipation increment increased with increasing plant density. Plant uptake accounted for only a small portion of the dissipation increments. Furthermore, P. crispus could evidently improve sediment redox potentials, and strong positive correlations between root surface area and the redox potential as well as between the redox potentials and the dissipation ratios of phenanthrene and pyrene were obtained, indicating that the oxygen released by the roots ofP. crispus might be the main mechanism by which P. crispus enhanced the dis- sipation of PAHs in sediments.

关键词： polycyclic aromatic hydrocarbons (PAHs) phytoremediation plant density Potamogeton crispus L. sediments

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设备使用过程中的故障分布及可靠度变化分析

重庆建筑大学学报 2006年第5期28卷 51-54页

作者：池洁重庆交通大学管理学院重庆400074

通过对设备故障影响因素、故障分布主要类型、可靠性变化的分析,研究了设备故障的分布类型(指数分布函数,威布尔分布函数),可靠性变化的计算,同时结合具体的实例来分析如何确定故障分布类型,以及如何确定设备可以达到的可靠性水平,并根... 详细信息

通过对设备故障影响因素、故障分布主要类型、可靠性变化的分析,研究了设备故障的分布类型(指数分布函数,威布尔分布函数),可靠性变化的计算,同时结合具体的实例来分析如何确定故障分布类型,以及如何确定设备可以达到的可靠性水平,并根据实际数据得到了ZW-17/29空压机在使用过程中的故障分布函数、可靠度变化。为制定设备的技术管理和维修管理计划提供理论方法。

关键词：设备管理设备故障可靠度分布函数