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Effects of chilling tolerance induced by spermidine pretreatment on antioxidative activity,endogenous hormones and ultrastructure of indica-japonica hybrid rice seedlings

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Journal of Integrative Agriculture 2016年第2期15卷 295-308页

作者： ZENG Yan-hua ZAHNG Yu-ping XIANG Jing WU Hui CHEN Hui-zhe ZHANG yi-kai ZHU De-feng College of Agronomy Nanjing Agricultural University State Key Laboratory of Rice Biology China National Rice Research Institute

Spermidine（Spd） is known to be involved in the regulation of plant responses to chilling stress and counteract the adverse effect of stress *** activities,endogenous hormones and ultrastructure change under chilling stress were investigated in indica-japonica hybrid rice seedlings.12-d-old seedlings were subjected to exogenous Spd（1 mmol L^（-1）） and then a chilling stress（6℃,4 d） was induced,followed by a subsequent recovery（25℃,4 d）.Results showed that malondialdehyde（MDA） and proline content were enhanced significantly,whereas shoot fresh and dry weights decreased during chilling stress and after recovery;chlorophyll content of chilling-stressed seedlings increased slightly but declined after recovery;additionally,total soluble sugar,sucrose,fructose and starch contents increased significantly during chilling stress,and only soluble sugar and fructose contents were observed in increase after recovery;chilling stress-induced increases in superoxide dismutase（SOD）,peroxidase（POD） and catalase（CAT） activities,but declined after recovery,and the level of ascorbate peroxidase was lower during chilling stress and after recovery;however,endogenous indole-3-acetic acid（IAA）,zeatin riboside（ZR）,gibberellic acid（GA_3）,and abscisic acid（ABA） levels were induced decreased compared with Spd *** microscopic analysis revealed that chilling stress-induced destruction of the chloroplast envelope during chilling stress and increased the number of plastoglobuli along with aberrations in thylakoid membranes after *** contrast,exogenous Spd protected rice seedlings from chilling-induced injuries in terms of lower malondialdehyde,proline and carbohydrates accumulation coupled with increased endogenous hormones *** recovery,Spd pretreatment chilling-exposed seedlings showed higher activities of antioxidant enzymes and normal physiological function of *** results suggest that Spd could promote effectively chilling tolera

关键词： polyamines chilling stress antioxidative activity endogenous hormones ultrastructure indica-japonica hybrid rice(Oryza sativa L.)

Thermal conductive proppant with self-suspension ability

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Petroleum Science 2023年第3期20卷 1742-1749页

作者： Guo-Qing Xu Xiu-Ping Lan Si-Si hao kai-yi Hu Si-Meng Qi Li-Dong Geng Quan Xu Yang Zhou Sinopec Key Laboratory of Drilling Completion and Fracturing of Shale Oil and Gas SINOPEC Research Institute of Petroleum Engineering Co.LtdBejing102249China State Key Laboratory of Petroleum Resources and Prospecting Bejing Key Laboratoryof Biogas Upgrading UtilizationHarvard SEAS-CUPB Joint Laboratory on Petroleum ScienceChina University of Petroleum(Beijing)Beijing102249China

The in situ mining technology is applied to the exploitation of medium-and low-maturity shale oil,which can use heaters to warm up the oil shale formations and pyrolyze the *** to the low thermal conductivity of oil shale,electric heaters need extra equipment to improve heat transfer *** this study,a thermally conductive proppant is fabricated by coating epoxy-resin and graphite on ceramic proppants for the first time,which could support the fracturing crack and transfer *** thermal conduction property of epoxy-resin and graphite coated proppants(EGPs)is 245%higher than that of uncoated proppants,which can transfer more heat to the oil shale formation and accelerate the conversion of *** adhesive property of EGPs is improved by 47.9%under the load force of 1500 nN,which prolongs the time for the fracture to *** summary,this novel proppant is expected to assist in-situ mining technology in the production of medium and low-maturity shale oil.

关键词： Exploitation of shaleoil In situ mining Technology Thermally conductive proppant Heat transfer

Enhancement of low-temperature toughness of Fe-Mn-C-Al alloy by rare earth Ce-modified inclusions

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Journal of Iron and Steel Research International 2024年第1期31卷 157-173页

作者： Guang-kai Yang Chang-ling Zhuang yi-zhuang Li Chen Hu Shao-bo Li College of Materials and Metallurgy Guizhou UniversityGuiyang550025GuizhouChina Department of Mechanical Engineering University of Hong KongHong Kong999077China The State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang110819LiaoningChina State Key Laboratory of Public Big Data Guizhou UniversityGuiyang550025GuizhouChina

Fe-Mn-C-Al alloys have been recognized as promising materials for certain low-temperature applications due to their exceptional mechanical properties and ***,their limited low-temperature toughness restricts their large-scale applications in specific *** influence of trace amounts of rare earth cerium(Ce)on the low-temperature toughness of Fe-18Mn-0.6C-1.8Al alloys was *** addition of Ce effectively alters the inclu-sions in the alloy,transforming large-sized irregular inclusions into fine ellipsoidal rare earth *** leads to a significant reduction in both the proportion and average size of the inclusions,resulting in their effective dispersion throughout the matrix and improved cryogenic *** presence of Ce-containing inclusions within the matrix reduces stress concentration,thereby inhibiting microcrack formation and improving impact absorption ***-cally,the addition of rare earth Ce alters the fracture behavior of the material at room temperature and low temperature,changing from brittle cleavage fracture to a more ductile failure *** impact toughness of the Fe-Mn-C-Al alloy is significantly improved by the addition of 0.0048 wt.%Ce,particularly at-196℃where the impact toughness reaches 103.6 J/cm^(2),representing an impressive improvement of 87.3%.

关键词： Fe-Mn-C-Al alloy Rare earth Low-temperature toughness Inclusion Fracture

Separation of cobalt and nickel by non-equilibrium solvent extraction

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Journal of Central South University of Technology 2001年第1期8卷 50-53页

作者： WANG kai yi, NIU Cong wei, QIAN Dong, LIU Ju hong, CHEN Xiao yi, LAI De yong (College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China) College of Chemistry and Chemical Engineering Central South University Changsha China

The separation of cobalt and nickel in the ammoniacal sulfate solution by non equilibrium solvent extraction with a phosphate (P303) as extractant was studied. In the experiment, the effects of equilibrium pH value in aqueous phase, contact time of the two phases, the air blowing time for feed liquor in the open beaker on percentage extraction of cobalt and nickel and percentage reextraction of nickel from the loaded organic phase with dilute H 2SO 4. etc were studied. The results showed that: Co(Ⅱ) can be oxidized to Co(Ⅲ) ammino complex by adding (NH 4) 2S 2O 8 or blowing air to the aqueous phase, and Co(Ⅲ) ammino complex is a kind of kinetically inert complex. Its extractive speed is very slow, while the nickel′s is much faster than that of cobalt. By controlling the contact time of the two phases, nickel can be separated from cobalt by non equilibrium solvent extraction. Then nickel was reextracted from the loaded organic phase with dilute H 2SO 4.

关键词： non equilibrium solvent extraction separation cobalt nickel

SILICON INTRAOCULAR LENSES IN 50 CATARACT CASES

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中华医学杂志(英文版) 1983年第3期96卷 176-176页

作者： Zhou kai-yi Jinniu Hospital Chengdu

Inplantation of silicon intraoicular lenses in 50 cataract eyes is reported. Of the 50 eyes, 42 were implanted immediately after extraction, while 8 were implanted in a second operation. 44 of the 50 blind eyes showed some degrees of recovery of vision: 14(31.8%) over 0.5, 13 (29.6%) 0.4-0.3, 14 (31.8%) 0.2-0.1 and 3 (6.8%) below 0.1. 6 were failures due to corneal edema.

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“讲演练纠评”五步教学法在航空航天心血管生理学实践课教学中的应用

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心脏杂志 2024年第1期36卷 64-68页

作者：张同梅铁娅滕范洁怡李程飞潘益凯李曦赵星成空军军医大学航空航天医学系航空航天医学训练教研室陕西西安710032

目的探讨“讲演练纠评”五步教学法在航空航天心血管生理学实践课教学中的应用及效果。方法选取空军军医大学2017级八年制航空航天医学专业和2021年、2022年航空军医任职教育培训班学员为研究对象,对照组为2021年航空军医任职教育培... 详细信息

目的探讨“讲演练纠评”五步教学法在航空航天心血管生理学实践课教学中的应用及效果。方法选取空军军医大学2017级八年制航空航天医学专业和2021年、2022年航空军医任职教育培训班学员为研究对象,对照组为2021年航空军医任职教育培训班学员采用传统讲授法(66人),试验组为2017级八年制航空航天医学专业学员(5人)和2022年航空军医任职教育培训班学员(42人)采用“讲演练纠评”五步教学法,根据成绩和满意度调查评价教学效果。结果对照组学员理论知识随堂测试成绩为(7.39±1.16)分,试验组为(8.96±0.48)分(满分10分,P<0.01);对照组操作考核成绩为(14.93±1.47)分,试验组为(16.97±1.64)分(满分20分,P<0.01)。试验组中89.36%的学生(42/47)认可“讲演练纠评”五步教学法。结论 “讲演练纠评”五步教学法可以激发学员的学习兴趣,有效提高航空航天心血管生理学实践课的授课效果,为其他相关实践课程的教学提供了新思路。

关键词：五步教学法航空航天医学航空航天心血管生理学实践课程

Hybridization-mediated quasiparticle and phonon dynamics in single crystal cerium films

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Science China(Physics,Mechanics & Astronomy) 2024年第4期67卷 146-153页

作者： Yunhe Pei yi Wu kai Hu Zhengxing Wei yiFeng Yang Yang Liu Jingbo Qi State Key Laboratory of Electronic Thin Films and Integrated Devices University of Electronic Science and Technology of ChinaChengdu 611731China Center for Correlated Matter and Department of Physics Zhejiang UniversityHangzhou 310058China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Songshan Lake Materials Laboratory Dongguan 523808China Collaborative Innovation Center of Advanced Microstructures Nanjing UniversityNanjing 210093China

We report the ultrafast optical pump-probe spectroscopy measurements on the single-crystal cerium *** experimental results of temperature-dependent quasiparticle dynamics reveal development of the hybridization between localized f moments and conduction electrons,i.e.,evolving from fluctuating hybridization to collective *** phonon renormalization is discovered to appear at the emerging temperature(T^(+))of fluctuating hybridization apart from its known presence at the coherent temperature(T^(*)),and can hardly be explained by the mean-field *** quasiparticle relaxation at high temperatures indicates coexistence of nonthermal electron-electron scattering and inelastic Kondo scattering,while its behavior at low temperatures suggests onset ofαphase in theγ-phase dominated *** also extract the indirect gap below T^(*),representing the appearance of collective *** findings provide novel information about the hybridization and phase evolution in the heavy fermion systems.

关键词： cerium quasiparticle dynamics hybridization phonon renormalization

STUDY ON APPLICATION OF EXPERT SYSTEMS IN ELECTROTECHNICS EDUCATION

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STUDY ON APPLICATION OF EXPERT SYSTEMS IN ELECTROTECHNICS ED...

Coupling vibration analysis of high-speed maglev train-viaduct systems with control loop failure

全国计算机辅助教育学会第五届学术年会

作者： SHI yi kai Northwestern Ploytechnical University

It is discussed in this paper that the status and future potential of knowledge based expert systems in relation to electro tcchinics practice and education.A chief research of application of expert systems in electrotcchnics education is *** In pace with rapid developments of Very Large Scale Integration(VLSI),Computer is

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Journal of Central South University 2022年第8期29卷 2771-2790页

作者： GUO Wei CHEN Xue-yuan YE yi-tao HU Yao LUO yi-kai SHAO Ping HUANG Ren-qiang WANG Xu-yixin GUO Zhen TAN Sui School of Civil Engineering Central South UniversityChangsha 410075China National Engineering Research Center of High-speed Railway Construction Technology Changsha 410075China Engineering Technology Research Center for Prefabricated Construction Industrialization of Hunan Province Changsha 410075China CCCC Highway Consultants Co. Ltd.Beijing 100088China School of Civil Engineering and Architecture Zhejiang UniversityHangzhou 310058China

The risk of failure of the control loop can occur when a high-speed maglev train runs on ***,the failure of the levitation magnets which balances the gravity of the maglev train could cause the train collision with *** study the dynamic response of the train and the viaduct when the levitation magnet control loop failure occurs,a high-speed maglev train-viaduct coupling model,which includes a maglev controller fitted by measured force-gap data and considers the actual structure of train and viaduct,is *** the accuracy and effectiveness of the established approach are validated by comparing the computed dynamic responses and frequencies with the measurement *** that,the dynamic responses of maglev train and viaduct are discussed under normal operation and control loop failures,and the most disadvantageous combination of control loop failures is *** results show that when a single control loop fails,it only has a great influence on the failed electromagnet,and the maglev response of adjacent electromagnets has no obvious change and no collision *** there is a risk of rail collisions when the dual control loop fails.

关键词： high-speed maglev train control loop failure coupling vibration maglev control