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magnetic Long-Range Order and Colossal magnetoresistance Effect in Double Exchange Ladders

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Chinese Physics Letters 2001年第9期18卷 1264-1267页

作者： ma dong-mei ZOU Liang-Jian Institute of Solid State Physics Chinese Academy of SciencesHefei 230031 National Laboratory of Solid State Microstructures Nanjing UniversityNanjing 210093

By applying Bogoliubov's ineguality to double-exchange(DE) ladders, we show that the ferromagnetic(FM) order is absent in the new DE systems at finite temperatures. The incorporation of Jahn-Teller electron-phonon coupling, orbital degeneracy and on-site Coulomb interaction with the DE interaction do not preserve these orders. The long-wavelength thermal fluctuations of the spins oversome the DEFM correlation and destroy the FM orders. The implication of the absence of FM order on the transport of the DE ladders is discussed.

关键词： orders interaction ladder

根灌外源褪黑素对干旱胁迫下紫花苜蓿生理特性的影响研究

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草地学报 2024年第1期32卷 198-206页

作者：张玲麻冬梅刘晓霞马巧利侯汶君李嘉文苏立娜杭嘉慧宁夏大学西北土地退化与生态系统恢复省部共建国家重点实验室培育基地/西北退化生态系统恢复与重建教育部重点实验室宁夏大学生态环境学院宁夏银川750021 宁夏大学林业与草业学院宁夏银川750021

为探究褪黑素对干旱胁迫下紫花苜蓿(Medicago sativa L.)生长的影响,本研究以‘中苜3号’紫花苜蓿为试验材料,设置正常供水和干旱2个水分梯度,采用盆栽试验根灌不同浓度褪黑素,分析不同条件下幼苗表型、生理生化指标的变化。结果表明:90... 详细信息

为探究褪黑素对干旱胁迫下紫花苜蓿(Medicago sativa L.)生长的影响,本研究以‘中苜3号’紫花苜蓿为试验材料,设置正常供水和干旱2个水分梯度,采用盆栽试验根灌不同浓度褪黑素,分析不同条件下幼苗表型、生理生化指标的变化。结果表明:90μmol·L^(-1)褪黑素处理能够显著提高紫花苜蓿幼苗株高、茎粗、相对含水量、相对叶绿素含量,此外,90μmol·L^(-1)褪黑素处理显著增加干旱胁迫下紫花苜蓿幼苗叶片抗氧化酶活性及酶合成相关基因表达水平,并降低脯氨酸、可溶性糖含量及丙二醛、相对电导率、过氧化氢含量。综上所述,褪黑素提高干旱胁迫下紫花苜蓿幼苗抗氧化酶生物合成基因表达水平,增强抗氧化酶活性,清除过量活性氧,缓解膜损伤,提高幼苗抗旱性。

关键词：紫花苜蓿干旱褪黑素渗透调节抗氧化酶

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Chemistry and Process Optimization of V-Microalloyed N80-Class Seamless Casing Tube

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Journal of Iron and Steel Research International 2010年第3期17卷 72-78页

作者： PAN Tao YANG Cai-fu ma Yue XUE dong-mei ZHANG Yong-quan Division for Structural materials Central Iron and Steel Research Institute Beijing 100081 China

The complex effects of different nitrogen （N） contents and thermal routines on the microstructure and mechanical properties of 33Mn2V steels for N80-Class seamless casing tube application were investigated using Gleeble simulation technique. The results showed that the N additions of 0. 014 %- 0. 021 % in the steels for the in-line normalization process （ILNP） increased the strength while the toughngss remained at a high level as compared with the steel with N content of 0. 005 %. It was also revealed that the N addition of 0. 021%could enhance the performance combination of strength and toughness in the steels by using 700 ℃ as the cooling interrupted temperature （CIT） for the non in-line normalizing process （NILNP）. It was further evidenced that the toughness was improved at expense of strength to some degree in all the steels by decreasing reheating temperature for the ILNP, while an increase of CIT for NILNP severely impaired the toughness and slightly improve the strength in the high-N steel with N content of 0. 021%. This can be attributed to the dissolution and precipitation behavior of V（C,N）. The optimization of V （C,N） precipitation could be achieved by enhancing N. The precipitation of V（C, N） in austenite was promoted by cooling to a certain temperature lower than the A,1 for the ILNP. The V（C,N） particles formed in austenite contrib- uted to grain refinement by the VN-induced nucleation of intragranular ferrite, but as a result the effect of precipitation on strengthening would become weaker due to a decrease of the precipitation of V in ferrite.

关键词： seamless tube in-line normalizing V-N microalloying reheating mechanical properties Gleeble simulation

Control of aluminum distribution in ZSM-5 zeolite for enhancement of its catalytic performance for propane aromatization

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Frontiers of Chemical Science and Engineering 2024年第8期18卷 15-24页

作者： Zhao ma Dezhi Shi Sen Wang mei dong Weibin Fan State Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001China University of Chinese Academy of Sciences Beijing 100049China

Regulation of aluminum distribution in zeolite framework is an effective method for improving its catalytic performance for propane ***,we found that recrystallization and post-realuminization of ZSM-5 cannot only create hollow structures to enhance the diffusion ability,but also adjust the content and position of paired aluminum species in its *** characterizations results confirmed that increase of paired aluminum content and inducement of more aluminum atoms sited in the intersection cavity are beneficial to the formation of aromatic products in propane *** a result,the hollow-structured ZSM-5 zeolite with more paired aluminum(H-200-hollow)showed higher propane conversion and aromatics selectivity than other samples at the same *** catalytic performance of H-200-hollow can be further improved by ion-exchanging with a small amount of Ga(III)*** propane conversion and aromatics selectivity of Ga-200-hollow reached as high as 95%and 70%,respectively,at 540°C and 1 atm.

关键词： propane aromatization zeolite aluminum distribution recrystallization and post-realuminization

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数字兵器下的数据治理

中国标准化 2024年第12期 55-59页

作者：郭蕊苗洋王广福罗娜马冬梅吉林江机特种工业有限公司

军工企业面临数字化转型和智能化升级,数据是此项工程的战略资源,信息化发展过程中持续产生大量数据,数字兵器建设中必将产生更多的数据。如何收集利用数据、挖掘数据潜在价值是大部分企业面临的问题。国内大型企业数据治理已成趋势,数... 详细信息

军工企业面临数字化转型和智能化升级,数据是此项工程的战略资源,信息化发展过程中持续产生大量数据,数字兵器建设中必将产生更多的数据。如何收集利用数据、挖掘数据潜在价值是大部分企业面临的问题。国内大型企业数据治理已成趋势,数据治理是提高数据标准化、提升数据质量的重要方法。本文通过介绍数据治理的概念,分析数据问题,强调数据治理的意义和必要性,对如何开展数据治理以及数据治理过程的关键问题展开讨论,为军工企业数据管理提供理论和实践价值。

关键词：数字兵器数据数据质量数据治理

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基于中医传承辅助系统分析熊磊教授治疗小儿咳嗽变异性哮喘的方药规律

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云南中医中药杂志 2024年第7期45卷 23-27页

作者：聂坚马冬梅吴云霞贾永蕊闫晓东熊磊云南中医药大学云南昆明650500 昭通市中医医院云南昭通657000

目的运用中医传承辅助系统,分析云南省名中医熊磊教授临床治疗小儿咳嗽变异性哮喘的方药使用规律及特色。方法 2020年9月-2021年9月收集熊磊教授临床治疗小儿咳嗽变异性哮喘的处方共95张,基于中医传承辅助系统中的熵聚类算法,得到其治... 详细信息

目的运用中医传承辅助系统,分析云南省名中医熊磊教授临床治疗小儿咳嗽变异性哮喘的方药使用规律及特色。方法 2020年9月-2021年9月收集熊磊教授临床治疗小儿咳嗽变异性哮喘的处方共95张,基于中医传承辅助系统中的熵聚类算法,得到其治疗该病的方药规律。结果将按标准选入的处方进行数据统计并分析,总结出方药使用的规律,得到新处方5首以及核心组合14个。结论熊磊教授临床善治小儿咳嗽,具有丰富的临床经验,疗效独到,创立验方—百诃清金汤,具有风痰火共调、肺肝脾同治的组方特点,值得学习借鉴。

关键词：百诃清金汤名医熊磊中医传承辅助平台数据挖掘咳嗽变异性哮喘用药特色

Copper slag assisted coke reduction of phosphogypsum for sulphur dioxide preparation

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Chinese Journal of Chemical Engineering 2024年第1期65卷 43-53页

作者： dong ma Qinhui Wang State Key Laboratory of Clean Energy Utilization Institute for Thermal Power EngineeringZhejiang UniversityHangzhou 310027China

The reduction of phosphogypsum(PG)to lime slag and SO_(2)using coke can effectively alleviate the environmental problems caused by ***,the PG decomposition temperature remains high and the product yield remains *** adding additives,the decomposition temperature can be further reduced and PG decomposition rate and product yield can be ***,the use of current additives such as Fe_(2)O_(3)and SiO_(2)brings the problem of increasing economic ***,it is proposed to use solid waste copper slag(CS)as a new additive to reduce PG to prepare SO2,which can reduce the cost and meet the environmental benefits at the same *** effects of proportion,temperature and thermostatic time on PG decomposition are investigated by experimental and kinetic analysis combined with FactSage thermodynamic calculations to optimize the roasting ***,the reaction mechanism is *** is found that adding CS to the coke and PG system can increase the rate of PG decomposition and SO_(2)yield while lowering the PG decomposition *** example,when the CS/PG mass ratio increases from 0 to 1,PG decomposition rate increases from 83.38%to 99.35%,SO_(2)yield increases from 78.62%to 96.81%,and PG decomposition temperature decreases from 992.4℃to 949.6℃.The optimal reaction parameters are CS/PG mass ratio of 1,Coke/PG mass ratio of 0.06 at 1100℃for 20 min with 99.35%PG decomposition rate and 96.81%SO_(2) *** process proceeds according to the following reactions:2CaSO_(4)+ 0.7C + 0.8Fe_(2)SiO_(4)→0.8Ca_(2)SiO_(4)+ 0.2Ca_(2)Fe_(2)O_(5)+ 0.4Fe_(3)O_(4)+2SO_(2)+ 0.7CO_(2)Finally,a process for decomposing PG with coke and CS is proposed.

关键词： Phosphogypsum Sulfur dioxide Copper slag Fluidized-bed Reduction Waste treatment

Finite-time Prescribed Performance Time-Varying Formation Control for Second-Order Multi-Agent Systems With Non-Strict Feedback Based on a Neural Network Observer

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 1039-1050页

作者： Chi ma Dianbiao dong the School of Mechanical Engineering Northwestern Polytechnical UniversityXi’an 710072China

This paper studies the problem of time-varying formation control with finite-time prescribed performance for nonstrict feedback second-order multi-agent systems with unmeasured states and unknown *** eliminate nonlinearities,neural networks are applied to approximate the inherent dynamics of the *** addition,due to the limitations of the actual working conditions,each follower agent can only obtain the locally measurable partial state information of the leader *** address this problem,a neural network state observer based on the leader state information is ***,a finite-time prescribed performance adaptive output feedback control strategy is proposed by restricting the sliding mode surface to a prescribed region,which ensures that the closed-loop system has practical finite-time stability and that formation errors of the multi-agent systems converge to the prescribed performance bound in finite ***,a numerical simulation is provided to demonstrate the practicality and effectiveness of the developed algorithm.

关键词： Finite-time control multi-agent systems neural network prescribed performance control time-varying formation control

Liquid-phase epitaxial layer by layer brushing fabrication of metalorganic frameworks films

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Nano Research 2024年第6期17卷 5698-5704页

作者： Li-mei Chang Rui Zhai Zhi-Zhou ma Jian-dong Huang Zhi-Gang Gu Jian Zhang College of Chemistry Fuzhou UniversityFuzhou 350108China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China University of Chinese Academy of Sciences Beijing 100049China

Development of metal-organic framework(MOF)films is of great importance to expand their ***,we report a facile and universal method of liquid-phase epitaxial(LPE)layer by layer(LBL)brushing approach for fabricating MOF films on various substrates in a high-throughput *** MOF films preparation method offers a great prospective to cost-effectively construct films with short preparation time and little reagent ***,this LBL brushing approach has been implemented successfully to assemble various MOF films,including HKUST-1,zeolitic imidazolate framework-8(ZIF-8),Cu(bdc),and Cu_(2)(L)_(2)P(L=bdc,ndc,and cam;P=dabco and bipy).Afterwards,the classic MOF HKUST-1 and ZIF-8 films were grown on sensor chip electrode and porous fiber support for good volatile organic compounds(VOCs)selective sensing and water purification *** study demonstrates that this LBL brushing preparation method can be employed to synthesize various MOF films with a variety of characteristics to realize their sensing and separation applications.

关键词： metal-organic framework porous materials layer by layer fabrication film