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Effects of collapsing gully erosion on soil qualities of fa.m fields in the hilly granitic region of South China

Journal of Integrative Agriculture 2016年第12期15卷 2873-2885页

作者： xia Dong DING Shu-wen LONG Li DENG Yu-song WANG Qiu-xia WANG Shu-ling CAI Chong-fa College of Resources and Environment Huazhong Agricultural University Wuhan 430070 P.R. China Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River) Ministry of Agriculture/Huazhong Agricultural University Wuhan 430070 P.R. China Sichuan Research Institute of Water Conservancy Science Chengdu 610072 P.R.China

Collapsing gully erosion is a specific form of soil erosion types in the hilly granitic region of tropical and subtropical South China, and can result in extremely rapid water and soil loss. Knowledge of the soil physical and chemical properties of fa.mland influenced by collapsing gully erosion is important in understanding the development of soil quality. This study was conducted at the Wuli Watershed of the Tongcheng County, south of Hubei Province, China. The aim is to investigate soil physical and chemical properties of three soil layers （0-20, 20-40 and 40-60 cm） for two fa.mland types （paddy field and upland field） in three regions influenced by collapsing gully erosion. The three regions are described as follows： strongly influenced region （SIR）, weakly influenced region （WIR） and non-influenced region （NIR）. The results show that collapsing gully erosion significantly increased the soil gravel and sand content in paddy and upland fields, especially the surfa.e soil in the SIR and WIR. In the 0-20 cm layer of the paddy field, the highest gravel content （250.94 g kg-1） was in the SIR and the lowest （78.67 g kg-1） was in the NIR, but in the upland filed, the surfa.e soil （0-20 cm） of the SIR and the 40-60 cm soil layer for the NIR had the highest （177.13 g kg-1） and the lowest （59.96 g kg-1） values of gravel content, respectively. The distribution of gravel and sand decreased with depth in the three influenced regions, but silt and clay showed the inverse change. In the paddy field, the average of sand content decreased from 58.6 （in the SIR） to 49.0% （in the NIR）, but the silt content was in a reverse order, increasing from 27.9 to 36.9%, and the average of the clay content of three regions showed no significant variation （P〈0.05）. But in the upland filed, the sand, silt and clay fluctuated in the NIR and the WIR. Soils in the paddy and upland field were highly acidic （pH〈5.2） in the SIR and WIR; moreover lower nutrient contents （soil organic matter （SOM）, to

关键词： collapsing gully erosion fa.mland hilly granitic region soil nutrient soil properties South China

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Induction of immune tolerance with heart-thymus composite allotransplantation in rats

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Journal of Central South University of Technology 2005年第Z1期12卷 331-336页

作者： XIONG Hai-bo xia Sui-sheng WEN Hao HUANG Zu-fa.YE Qi-fa Medical Academy of Transplantation the Third Xiangya Hospital Central South University Changsha 410013 China Institute of Transplantation Tongji Hospital Huazhong Science and Technological University Wuhan 430030 China Department of General Surgery the First Affiliated Hospital Xinjiang Medical University Urumqi 830054 China Medical Academy of Transplantation the Third Xiangya Hospital Central South University Changsha 410013 China Medical Academy of Transplantation the Third Xiangya Hospital Central South University Changsha 410013 China

Objective To study on the role of thymus transplantation for heart allograft in rats. Methods Vascularized heart-thymus combined transplantation was performed with microsurgical technique. Graft survival, histopathology, level of IL-2, IL-4 and its mRNA expression in serum and cardiac grafts were investigated. Results Heart-thymus combined transplantation achieved effect in the prolongation of cardiac graft survival with short-term administration of cyclosporine. Conclusions Vascularized thymus transplantation induced immune tolerance in thymectomized rats.

关键词： thymus transplantation immune tolerance rejection rat

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Cyclotron dynamics of neutral atoms in optical lattices with additional magnetic field and harmonic trap potential

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Chinese Physics B 2020年第1期29卷 156-163页

作者： Ai-xia Zhang Ying Zhang Yan-fa.g Jiang Zi-fa.Yu Li-xia Cai Ju-Kui Xue College of Physics and Electronic Engineering Northwest Normal University

We analytically and numerically discuss the stability and dynamics of neutral atoms in a two-dimensional optical lattice subjected to an additional harmonic trap potential and artificial magnetic *** harmonic trap potential plays a key role in modifying the equilibrium state properties of the system and stabilizing the cyclotron orbits of the ***,the presence of the harmonic trap potential and lattice potential results in rich cyclotron dynamics of the *** coupling effects of lattice potential,artificial magnetic field,and harmonic trap potential lead to single periodic,multi-periodic or quasi-periodic cyclotron orbits of the *** we can control the cyclotron dynamics of neutral atoms in optical lattice by manipulating the strength of harmonic confinement,artificial magnetic field,and initial *** results provide a direct theoretical evidence for the cyclotron dynamics of neutral atoms in optical lattices exposed to the artificial gauge magnetic field and harmonic trap potential.

关键词： Bose–Einstein condensate artificial magnetic field optical lattice

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A new mathematical model for horizontal wells with variable density perforation completion in bottom water reservoirs

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Petroleum Science 2017年第2期14卷 383-394页

作者： Dian-fa.Du Yan-Yan Wang Yan-Wu Zhao Pu-Sen Sui Xi xia School of Petroleum Engineering China University of Petroleum Sinopec Petroleum Exploration and Production Research Institute Sinopec Shengli Production Plant Shengli Oilfield Branch CompanySinopec

Horizontal wells are commonly used in bottom water reservoirs,which can increase contact area between wellbores and *** are many completion methods used to control cresting,among which variable density perforation is an effective *** is difficult to evaluate well productivity and to analyze inflow profiles of horizontal wells with quantities of unevenly distributed perforations,which are characterized by different *** this paper,fluid flow in each wellbore perforation,as well as the reservoir,was analyzed.A comprehensive model,coupling the fluid flow in the reservoir and the wellbore pressure drawdown,was developed based on potential functions and solved using the numerical discrete ***,a bottom water cresting model was established on the basis of the piston-like displacement ***,bottom water cresting parameters and fa.tors influencing inflow profile were analyzed.A more systematic optimization method was proposed by introducing the concept of cumulative free-water production,which could maintain a balance（or then a balance is achieved）between stabilizing oil production and controlling bottom water *** show that the inflow profile is affected by the perforation *** with denser perforation density at the toe end and thinner density at the heel end may obtain low production,but the water breakthrough time is *** cumulative free-water production as a parameter to evaluate perforation strategies is advisable in bottom water reservoirs.

关键词： Bottom water reservoirs Variable density perforation completion Inflow profile Cresting model Cumulative free-water production

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回火热处理在复合消音锯片加工过程中的影响和作用

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热处理技术与装备 2024年第1期45卷 20-23页

作者：夏昌龙韩涛张露方发强黑旋风锯业股份有限公司湖北宜昌443003

针对复合消音锯片生产过程中的点焊热变形问题,通过优化回火工艺参数,采用中温上限回火和缩短保温时间的二次梯度回火工艺,使点焊后的热应力得到最大程度消除,从而改善二次回火后消音锯片的平面度和端跳值等指标。为后续磨削和校平的处... 详细信息

针对复合消音锯片生产过程中的点焊热变形问题,通过优化回火工艺参数,采用中温上限回火和缩短保温时间的二次梯度回火工艺,使点焊后的热应力得到最大程度消除,从而改善二次回火后消音锯片的平面度和端跳值等指标。为后续磨削和校平的处理减轻加工难度,同时稳定地控制和保证复合消音锯片的实物质量水平。

关键词：金刚石复合消音锯片点焊热应力变形回火平面度

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基于多元回归的延安市PM2.5浓度预测

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信息技术 2024年第5期48卷 15-21页

作者：王思源任瑛夏必胜王文发延安大学数学与计算机科学学院陕西延安716000

工业化进程的加快带来的不只是经济的飞速发展,还有以PM2.5为主的污染物浓度的增加,给人类的健康以及环境的治理带来不利影响,合理有效的PM2.5浓度预测对于人类健康和环境治理有着重要意义。文中设计了基于多元回归模型的PM2.5浓度预测... 详细信息

工业化进程的加快带来的不只是经济的飞速发展,还有以PM2.5为主的污染物浓度的增加,给人类的健康以及环境的治理带来不利影响,合理有效的PM2.5浓度预测对于人类健康和环境治理有着重要意义。文中设计了基于多元回归模型的PM2.5浓度预测模型,分别预测了延安市春季、夏季、秋季和冬季的PM2.5浓度,与极限树回归、Catboost回归和K邻近回归等回归模型的预测结果进行对比。结果表明多元回归模型的误差较小,拟合精度较高,为延安市大气污染的治理提供了可靠的科学依据。

关键词：多元回归 PM2.5预测极限树回归随机森林

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Cefoperazone sodium/sulbactam sodium vs piperacillin sodium/tazobactam sodium for treatment of respiratory tract infection in elderly patients

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World Journal of Clinical Cases 2021年第29期9卷 8694-8701页

作者： xiao-xia Wang Cheng-Tai Ma Yan-xia Jiang Yun-Jie Ge fa.Yun Liu Wen-Gang Xu Department of Cadre Health Qingdao Municipal HospitalQingdao 266011Shandong ProvinceChina Department of Emergency Medicine The Affiliated Hospital of Qingdao UniversityQingdao 266011Shandong ProvinceChina Department of Pathology The Affiliated Hospital of Qingdao UniversityQingdao 266011Shandong ProvinceChina Department of Pulmonary Shandong Qingdao Hospital of Integrated Traditional Chinese and Western MedicineQingdao 266011Shandong ProvinceChina

BACKGROUND Respiratory tract infections in the elderly are difficult to cure and can easily recur,thereby posing a great threat to patient prognosis and quality of *** To investigate the therapeutic effects of different antibiotics in elderly patients with respiratory tract *** Seventy-four elderly patients with respiratory tract infection were randomly allocated to a study(n=37;treated with cefoperazone sodium/sulbactam sodium)or control(n=37;treated with piperacillin sodium/tazobactam sodium on the basis of routine symptomatic support)*** groups were treated for 7 *** to symptom relief(leukocyte recovery;body temperature recovery;cough and sputum disappearance;and rale disappearance time),treatment effect,and laboratory indexes[procalcitonin(PCT),C-reactive protein(CRP),white blood cell count(WBC),and neutrophil percentage(NE)]before and 7 d after treatment and the incidence of adverse reactions were *** In the study group,the time to WBC normalization(6.79±2.09 d),time to body temperature normalization(4.15±1.08 d),time to disappearance of cough and sputum(6.19±1.56 d),and time to disappearance of rales(6.68±1.43 d)were shorter than those of the control group(8.89±2.32 d,5.81±1.33 d,8.77±2.11 d,and 8.69±2.12 d,respectively;P=0.000).Total effective rate was higher in the study group(94.59%vs 75.68%,P=0.022).Serum PCT(12.89±3.96μg/L),CRP(19.62±6.44 mg/L),WBC(20.61±6.38×10^(9)/L),and NE(86.14±7.21%)levels of the study group before treatment were similar to those of the control group(14.05±4.11μg/L,18.79±5.96 mg/L,21.21±5.59×10^(9)/L,and 84.39±6.95%,respectively)with no significant differences(P=0.220,0.567,0.668,and 0.291,respectively).After 7 d of treatment,serum PCT,CRP,WBC,and NE levels in the two groups were lower than those before *** PCT(2.01±0.56μg/L),CRP(3.11±1.02 mg/L),WBC(5.10±1.83×10^(9)/L),and NE(56.35±7.17%)levels were lower in the study group than in the control group(3.29±0.64μg/L,5.67±1.23 mg/L,8.

关键词： Cefoperazone sodium Sulbactam sodium Piperacillin sodium Tazobactam sodium Respiratory tract infection Elderly

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我国3省市门诊中老年慢性疼痛病人的流行特征分析

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中国疼痛医学杂志 2024年第5期30卷 341-347页

作者：杜成欣张伟伟许丽媛樊碧发董建群颜流霞姜莹莹中国疾病预防控制中心慢性非传染性疾病预防控制中心北京2100050 中日友好医院疼痛科北京100029

目的:调查了解我国3省市门诊中老年慢性疼痛病人流行特征。方法:2023年4月至8月采用多阶段分层抽样方法,在北京市、重庆市、江西省各抽取1家三级甲等综合医院和二级甲等综合医院,纳入年龄≥45岁、主诉疼痛时间持续超过3个月的门诊慢性... 详细信息

目的:调查了解我国3省市门诊中老年慢性疼痛病人流行特征。方法:2023年4月至8月采用多阶段分层抽样方法,在北京市、重庆市、江西省各抽取1家三级甲等综合医院和二级甲等综合医院,纳入年龄≥45岁、主诉疼痛时间持续超过3个月的门诊慢性疼痛病人。通过问卷调查了解调查对象的一般情况和慢性疼痛流行特征。计数资料用率表示,采用秩和检验分析单向有序资料,趋势χ^(2)检验分析双向有序资料,采用二元logistic回归分析病人疼痛程度的影响因素。结果:纳入分析的有效样本为4151例,其中男性1803例(43.4%)、女性2348例(56.6%);45~64岁2193例(52.8%)、≥65岁1958例(47.2%)。疼痛轻、中、重度分别为1079例(26.0%)、2535例(61.1%)、537例(12.9%)。慢性疼痛病人的疼痛程度在年龄(χ^(2)=39.061,P<0.001)、东中西部地区(Z=768.542,P<0.001)、城乡地域(Z=-10.513,P<0.001)、文化程度(χ^(2)=4.280,P<0.05)、家庭年收入(χ^(2)=26.707,P<0.001)、是否有既往病史(Z=-3.685,P<0.001)、饮酒状况(χ^(2)=10.172,P<0.01)、疼痛年限(χ^(2)=12.617,P<0.001)、疼痛部位数量(χ^(2)=106.442,P<0.001)的比较中差异有统计学意义(P<0.05)。二元logistic回归分析结果显示,年龄≥65岁(OR=1.69,95%CI:1.38-2.07)、居住在农村地域(OR=2.09,95%CI:1.58-2.77)、文化程度大专及以上(OR=1.48,95%CI:1.10-2.00)、疼痛部位数量≥2处(OR=1.73,95%CI:1.42-2.10)是重度疼痛的危险因素(P<0.05)。结论:我国3省市门诊中老年慢性疼痛病人以中度疼痛为主。年龄高低、城乡地域、文化程度、疼痛部位多寡是疼痛程度的重要影响因素。应尽早识别和干预相关影响因素,以便更全面地评估疼痛程度和制定个性化的治疗方案,从而改善病人疼痛治疗和管理效果。

关键词：中老年慢性疼痛疼痛程度影响因素

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Recent advances of ferro-/piezoelectric polarization effect for dendrite-free metal anodes

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稀有金属:英文版 2023年第8期42卷 2516-2544页

作者： Hai-xia Zhang Peng-Fei Wang Chuan-Gang Yao Shi-Peng Chen Ke-Di Cai fa.Nian Shi School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China School of Environmental and Chemical Engineering Shenyang University of TechnologyShenyang 110870China College of Chemistry and Materials Engineering Bohai UniversityJinzhou 121013China

Metal anodes based on plating/stripping electrochemistry,for instance,common alkaline metal lithium(Li),sodium(Na),potassium(K),polyvalent metal magnesium(Mg),aluminum(Al),calcium(Ca)and zinc(Zn)are imminently evoked and increasingly researched for future generation high-energy-density rechargeable batteries due to their large theoretical capacity,low electrochemical potential,and superior electronic conductivity in recent ***,the uncontrolled dendrite formation issue induces low Coulombic efficiency,short lifespan,and hazardous security risks,hindering the actual applications of metal *** various solutions,the utilization of ferro-/piezoelectric materials for metal anodes displays active effects on decreasing local current density,suppressing dendrite growth,and tolerating volume expansion benefits from the unique ferro-/piezoelectric polarization *** review presents the research progress of ferro-/piezoelectric polarization effect for regulating the dendritic growth of metal anodes for the first ***,the current challenges and strategies of metal anodes are ***,ferro-/piezoelectric materials and their working principle are ***,the recent research progress of ferroelectric and piezoelectric materials on dynamic regulation of dendrite growth is summarized,and the future perspectives are *** hope this review could draw more attention in designing metal anodes with self-polarization materials and promoting their practical applications.

关键词： Metal anode Ferro-/piezoelectric material Polarization effect Dendrite-free Lithium Perovskite

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Effect of Ti and rare earth on microsegregation and large-sized precipitates of H13 steel

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Journal of Iron and Steel Research International 2021年第12期28卷 1591-1604页

作者： fa.Ji Rui Xu Yu-long Gao Qing-chao Tian Lu Wang Zhi-xia xiao Fu-xing Yin School of Materials Science and Engineering Hebei University of TechnologyTianjin300130China Research Institute for Energy Equipment Materials Hebei University of TechnologyTianjin300130China State Key Laboratory of Advanced Special Steel&Shanghai Key Laboratory of Advanced Ferrometallurgy&School of Materials Science and Engineering Shanghai UniversityShanghai200444China

Large-sized precipitates are fa.al to the thermal fa.igue of H13 hot work die *** amounts of Ti and/or rare earth(RE)were added in H13 steel during electroslag remelting to improve the element segregation and refine the large-sized *** results show that as Ti content increases from 0.0032 to 0.057 wt.%,the segregation of Cr,Mo and V becomes more severe.V-rich M(C,N)carbides are shorter,and their branches are denser in 3D ***,the number density of V-rich M(C,N)carbides with a size less than 2μm increases and that with other sizes *** addition,Ti-rich MN nitrides with the size greater than 4μm increases significantly at high Ti *** RE content increases from 0.0051 to 0.036 wt.%,the segregation of main alloying elements is first weakened and then *** with that in RE-free H13 steel,V-rich M(C,N)carbides are less developed in 3D observation,and the change in number density is similar to that of Ti-modified *** composite modification of 0.024 wt.%Ti and 0.011 wt.%RE,the segregation of alloying element and V-rich M(C,N)carbides are not significantly improved.

关键词： H13 steel Segregation Primary carbide Ti Rare earth Precipitate

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