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Genesis of Polyhalite in the Halite in Jialingjiang Formation of Triassic,Eastern Sichuan Basin,China

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Acta Geologica Sinica(English Edition) 2014年第S1期88卷 283-284页

作者： ZHAO Yanjun LIU Chenglin wang lichen DING Ting wang Mingquan Institute of Mineral Resources Chinese Academy of Geological Sciences China University of Geosciences

Polyhalite generally formed in the early diagenetic *** is formed by the brine which rich in K+and Mg2+and adverse reaction with the gypsum,anhydrite,glauberite(Pierre,1985;Peryt et al.,2005;Leitner et al.,

关键词： polyhalite halite Jialingjiang Formation Triassic Sichuan Basin

Revision of P-wave Velocity and Thickness of Hydrate Layer in Shenhu Area, South China Sea

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Journal of Ocean University of China 2014年第5期13卷 742-746页

作者： GONG Jianming ZHANG Xunhua ZOU Changchun CHEN Qiang wang lichen YUAN Chunfang HU Gaowei JIANG Yubo Key Laboratory of Marine Hydrocarbon Resources and Environmental Geology Qingdao Institute of Marine Geology School of Geophysics and Information Technology China University of Geosciences (Beijing) College of Geoscience and Surveying Engineering China University of Mining and Technology (Beijing) College of Marine Geosciences Ocean University of China

To revise P-wave velocity and thickness of the hydrate layer in the Shenhu area of the South China Sea, acoustic and resistivity logging curves are reanalyzed. The waterlogging phenomenon is found in the shallow sediments of five drilling wells, which causes P-wave velocity to approximate the propagation velocity of sea water(about 1500 m s-1). This also affects the identification of the hydrate layer and results in the underestimate of its thickness. In addition, because there could be about a 5 m thick velocity ramp above or below the hydrate layer as interpreted by acoustic and resistivity logging curves, the recalibrated thickness of this layer is less than the original estimated thickness. The recalibrated P-wave velocity of the hydrate layer is also higher than the original estimated velocity. For the drilling well with a relatively thin hydrate layer, the velocity ramp plays a more important role in identifying and determining the thickness of the layer.

关键词： velocity ramp thickness hydrate layer Shenhu area

Giant low-field magnetocaloric effect in ferromagnetically ordered Er_(1-x)Tm_(x)Al_(2)(0≤x≤1)compounds

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Journal of Materials Science & Technology 2023年第15期146卷 168-176页

作者： Shuxian Yang Xinqi Zheng Dingsong wang Juping Xu Wen Yin Lei Xi Chaofan Liu Jun Liu Jiawang Xu Hu Zhang Zhiyi Xu lichen wang Yihong Yao Maosen Zhang Yichi Zhang Jianxin Shen Shouguo wang Baogen Shen School of Materials Science and Engineering Beijing Advanced Innovation Center for Materials Genome EngineeringUniversity of Science and Technology BeijingBeijing 100083China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of Sciences&University of Chinese Academy of SciencesBeijing 100190China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Spallation Neutron Source Science Center Dongguan 523803China School of Materials Science and Engineering Anhui UniversityHefei 230601China Department of Energy and Power Engineering School of Mechanical EngineeringBeijing Institute of TechnologyBeijing 100081China Songshan Lake Materials Laboratory Dongguan 523808China Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou 341000China Ningbo Institute of Materials Technology and Engineering Chinese Academy of SciencesNingbo 315201China

Magnetocaloric material is the key working substance for magnetic refrigerant technology,for which the low-field and low-temperature magnetocaloric effect(MCE)performance is of great importance for practical applications at low ***,a giant low-field magnetocaloric effect in ferromagnetically ordered Er_(1-x)Tm_(x)Al_(2)(0≤x≤1)compounds was reported,and the magnetic structure was characterized based on low-temperature neutron powder *** increasing Tm content from 0 to 1,the Curie temperature of Er_(1-x)Tm_(x)Al_(2)(0≤x≤1)compounds decreases from 16.0 K to 3.6 *** Er_(0.7)Tm_(0.3)Al_(2) compound,it showed the largest low-field magnetic entropy change(–SM)with the peak value of 17.2 and 25.7 J/(kg K)for 0–1 T and 0–2 T,***(–SM)max up to 17.2 J/(kg K)of Er0.7Tm0.3Al2 compound for 0–1 T is the largest among the intermetallic magnetocaloric materials ever reported at temperatures below 20 *** peak value of adiabatic temperature change(Tad)max was determined as 4.13 K and 6.87 K for 0–1 T and 0–2 T,*** characteristic of second-order magnetic transitions was confirmed on basis of Arrott plots,the quantitative criterion of exponent n,rescaled universal curves,and the mean-field theory *** outstanding low-field MCE performance with low working temperatures indicates that Er_(1-x)Tm_(x)Al_(2)(0≤x≤1)compounds are promising candidates for magnetic cooling materials at liquid hydrogen and liquid helium temperatures.

关键词： Magnetocaloric effect Low field magnetocaloric effect Magnetic structure RAl_(2)compounds

Classification and Prediction of Skyrmion Material Based on Machine Learning

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Research 2023年第4期2023卷 281-291页

作者： Dan Liu Zhixin Liu JinE Zhang Yinong Yin Jianfeng Xi lichen wang JieFu Xiong Ming Zhang Tongyun Zhao Jiaying Jin Fengxia Hu Jirong Sun Jun Shen Baogen Shen Department of Physics School of Artificial IntelligenceBeijing Technology and Business UniversityBeijing 100048P.R.China School of Integrated Circuit Science and Engineering Beihang UniversityBeijing 100191China Ningbo Institute of Materials Technology&EngineeringChinese Academy of SciencesZhejiang 315201P.R.China School of Physics Inner Mongolia University of Science and TechnologyBaotou 014010P.R.China State Key Laboratory of Magnetism Institute of PhysicsChinese Academy of SciencesBeijing 100190P.R.China School of Materials Science and Engineering Zhejiang UniversityHangzhou 310027P.R.China Key Laboratory of Cryogenics Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190P.R.China

The discovery and study of skyrmion materials play an important role in basic frontier physics research and future information *** database of 196 materials,including 64 skyrmions,was established and predicted based on machine learning.A variety of intrinsic features are classified to optimize the model,and more than a dozen methods had been used to estimate the existence of skyrmion in magnetic materials,such as support vector machines,k-nearest neighbor,and ensembles of *** is found that magnetic materials can be more accurately divided into skyrmion and non-skyrmion classes by using the classification of electronic *** that the rare earths are the key elements affecting the production of *** accuracy and reliability of random undersampling bagged trees were 87.5%and 0.89,respectively,which have the potential to build a reliable machine learning model from small *** existence of skyrmions in LaBaMnO is predicted by the trained model and verified by micromagnetic theory and experiments.

关键词： frontier earths verified

1-(3,4-二甲氧基)苯乙基-3-环氧丙基-5-氰基-6-甲基脲嘧啶的合成及晶体结构

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有机化学 2003年第10期23卷 1107-1110页

作者：张俊琪王礼琛中国药科大学有机化学教研室

标题化合物 1 ( 3 ,4 二甲氧基 )苯乙基 3 环氧丙基 5 氰基 6 甲基脲嘧啶是由 1 ( 3 ,4 二甲氧基 )苯乙基 5 氰基 6 甲基脲嘧啶在NaOH水溶液中与环氧氯丙烷反应制得 .结构通过单晶X射线衍射分析确定 ,其晶体属于单斜晶系 ,空间... 详细信息

标题化合物 1 ( 3 ,4 二甲氧基 )苯乙基 3 环氧丙基 5 氰基 6 甲基脲嘧啶是由 1 ( 3 ,4 二甲氧基 )苯乙基 5 氰基 6 甲基脲嘧啶在NaOH水溶液中与环氧氯丙烷反应制得 .结构通过单晶X射线衍射分析确定 ,其晶体属于单斜晶系 ,空间群P2 1/a ,晶胞参数 :a =1 0 9( 10 )nm ,b =1 43 ( 10 )nm ,c =1 2 0 ( 8)nm ,V =1 868nm3 ,Z =4,Dc=1 3 2Mg/m3 ,F( 0 0 0 ) =784.并用波谱法对分离得到的副产物进行了结构表征 .

关键词： 1-(3,4-二甲氧基)苯乙基-3-环氧丙基-5-氰基-6-甲基脲嘧啶合成晶体结构环氧氯丙烷

Influences of divalent ion substitution on the magnetic and dielectric properties of W-type barium ferrite

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Chinese Physics B 2024年第6期33卷 480-486页

作者：何诗悦刘若水刘煦婕叶先平王利晨沈保根 School of Rare Earths University of Science and Technology of ChinaHefei 230026China Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou 341119China Ningbo Institute of Materials Technology&Engineering Chinese Academy of SciencesNingbo 315201China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China

Saturation magnetization,magneto-crystalline anisotropy field,and dielectric properties are closely related to microwave devices applied at different *** regulating the magnetic and dielectric properties of W-type barium ferrites,single-phase BaMe_(2)Fe_(16)O_(27)(Me=Fe,Mn,Zn,Ni,Co) with different Me ions were synthesized by the high-temperature solid-state *** saturation magnetization(Ms) range from 47.77 emu/g to 95.34 emu/g and the magnetic anisotropy field(H_a) range from 10700.60 Oe(1 Oe=79.5775 A·m^(-1)) to 13739.57 Oe,depending on the type of cation substitution in the hexagonal *** dielectric permittivity and dielectric loss decrease with increasing frequency of the AC electric field in the low-frequency region,while they almost remain constant in the high-frequency *** charac teristics of easy regulation and preparation make it a potential candidate for use in microwave device applications.

关键词： W-type hexaferrite Raman spectra magnetic properties dielectric properties

基于磁偶极子的舰船轴频电磁场场源建模与试验验证

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西北工业大学学报 2016年第5期34卷 829-836页

作者：张立琛王英民郭拓西北工业大学航海学院陕西西安710072

根据舰艇水下腐蚀相关轴频电磁场的产生机理,提出了以电流环与磁偶极子等效性为线索,对舰艇轴频电磁场场源进行磁偶极子建模,并给出电流环的3种近似形状及环面积的计算方法。在盐湖进行了验证试验,结果表明:将磁偶极子作为对舰艇水下轴... 详细信息

根据舰艇水下腐蚀相关轴频电磁场的产生机理,提出了以电流环与磁偶极子等效性为线索,对舰艇轴频电磁场场源进行磁偶极子建模,并给出电流环的3种近似形状及环面积的计算方法。在盐湖进行了验证试验,结果表明:将磁偶极子作为对舰艇水下轴频电磁信号进行估算的数学模型是可行的,与电偶极子相比,由于考虑海水为导电媒质的特性,因而与试验结果更加吻合;磁偶极子模型与试验结果的一致性,表明提出的环面积计算方法是可行的。磁偶极子模型在提高模型精度的前提下减少了计算量和实测数据量,因此更适合用于舰船腐蚀相关轴频电磁场的研究。分析所得典型结论为进一步的应用研究奠定了基础。

关键词：轴频电磁场电偶极子模型磁偶极子模型导电媒质亥姆霍兹方程

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水稻栽植机械化区域型实现模式探讨

农机化研究 2010年第12期32卷 1-5,22页

作者：王海龙王立臣中国农业大学工学院北京100083

目前,我国的水稻生产机械化发展势头喜人,但是水稻栽植环节的机械化发展较慢,水平很低,成为水稻生产机械化过程中最突出和最薄弱的环节,这是提高水稻综合生产能力的重点和难点。我国水稻种植面积大、分布广,包括三大稻区(南方一季稻区... 详细信息

目前,我国的水稻生产机械化发展势头喜人,但是水稻栽植环节的机械化发展较慢,水平很低,成为水稻生产机械化过程中最突出和最薄弱的环节,这是提高水稻综合生产能力的重点和难点。我国水稻种植面积大、分布广,包括三大稻区(南方一季稻区、南方双季稻区和北方稻区)与5种类型(长江中下游一季稻区、西南稻区、长江流域双季稻区、华南双季稻区和北方稻区),基于我国水稻种植的区域化特点,坚持区域性的发展模式已经成为我国水稻栽植机械化发展的原则之一。根据初步的调查分析结果和各区域的实际生产,我国各个主要水稻产区现阶段应以水稻机械化插秧为基础,结合各自区域内的农业自然条件和经济社会发展水平,探索适合本区域的水稻栽植机械化实现模式。

关键词：水稻栽植机械化区域性实现模式

贺氏火针疗法治疗原发性下肢静脉曲张:随机对照研究

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中国针灸 2016年第3期36卷 231-236页

作者：王丽晨储开昀曾琳王麟鹏中国中医科学院眼科医院骨科北京100040 首都医科大学附属北京中医医院针灸中心北京100010 北京大学第三医院临床流行病学研究中心

目的:评价贺氏火针疗法治疗原发性下肢静脉曲张的临床疗效。方法:将50例原发性下肢静脉曲张患者随机分为观察组(25例)和对照组(25例)。观察组接受8周的贺氏火针疗法,以火针点刺曲张静脉,使瘀血流出并自止,再以毫针针刺患侧合阳、承筋、... 详细信息

目的:评价贺氏火针疗法治疗原发性下肢静脉曲张的临床疗效。方法:将50例原发性下肢静脉曲张患者随机分为观察组(25例)和对照组(25例)。观察组接受8周的贺氏火针疗法,以火针点刺曲张静脉,使瘀血流出并自止,再以毫针针刺患侧合阳、承筋、承山、昆仑。对照组在入组后8周内不予任何干预,定期接受随访,第8周后接受与观察组相同的治疗。主要评价指标是修订版静脉疾病临床严重程度评分(RVCSS),次要疗效指标包括静脉功能不全生活质量问卷(VEINES-QOL/Sym questionnaire)的症状评分(VEINES-Sym score)和生活质量评分(VEINES-QOL score)、洪堡静脉曲张严重程度评分(HVVSS)的症状评分。入组后及入组后第4周末、第8周末对两组进行评价,第16周末对观察组进行随访期评价。结果:研究期间共5例脱落,脱落率为10%。观察组RVCSS评分在第4周末和第8周末低于对照组(均P<0.05);观察组VEINES-QOL评分和HVVSS评分在第4周末和第8周末高于对照组(P<0.05,P<0.01);观察组VEINES-Sym评分与对照组相比,在第4周末和第8周末均有增加,但仅在第8周末时差异有统计学意义(P<0.01);观察组HVVSS评分在第8周末、第16周末与组内第4周末相比降低(均P<0.05)。结论:贺氏火针疗法治疗原发性下肢静脉曲张有效,可显著减轻疾病严重程度、减轻症状严重程度、减少症状发作频率,从而改善患者生活质量,并且在治疗后8周内仍保持较好的远期疗效。将疗程从4周增至8周,可明显提高贺氏火针疗法对症状严重程度的疗效。

关键词：原发性下肢静脉曲张贺氏火针针刺效应随机对照试验