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Variations and trends of the freezing and thaw- ing index along the Qinghai-Xizang Railway for 1966-2004

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Journal of Geographical Sciences 2008年第1期18卷 3-16页

作者： JIANG Fengqing hu Ruji li zhen Xinjiang Institute of Ecology and Geography CAS Urumqi 830011 China

Annual freezing and thawing index of 7 meteorological stations along the Qing- hai-Xizang Railway were calculated based on daily maximum and minimum temperature records for 1966-2004. Trends of annual freezing and thawing index were analyzed using the Mann-Kendall test and a simple linear regression method. The results show that： 1） The mean annual freezing indices range from 95 to 2300℃·d and the mean annual thawing indices range from 630 to 3250℃·d. The mean annual freezing index of the 7 stations exhibited decreasing trends with decreasing rate of -16.6- -59.1 ℃·d/10a. The mean annual thawing index of these 7 stations showed increasing trends with the related decreasing rate is 19.83-45.6℃·d/10a. 2） The MK trend test indicated the significant decreasing trends （significant at 〈 0.05 significant level） in the annual freezing index for most stations except for Golmud. The significant increasing trends can be observed in the annual thawing index for 4 stations except Golmud and Tuotuohe. Golmud was the only station with no trends in both annual freezing and annual thawing index.

关键词： freezing and thawing index global warming trends Qinghai-Xizang Railway

Root characteristics and yield of rice as affected by the cultivation pattern of strong seedlings with increased planting density and reduced nitrogen application

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Journal of Integrative Agriculture 2022年第5期21卷 1278-1289页

作者： GUAN Xian-jiao CHEN Jin CHEN Xian-mao XIE Jiang DENG Guo-qiang hu li-zhen li Yao QIAN Yin-fei QIU Cai-fei PENG Chun-rui Jiangxi Academy of Agricultural Sciences/Key Laboratory of Crop Ecophysiology and Farming System for the Middle and Lower Reaches of the Yangtze River Ministry of Agriculture and Rural Affairs/National Engineering and Technology Research Center for Red Soil ImprovementNanchang 330200P.R.China

To address the relationships between the amount of nitrogen fertilizer application and the yield of double cropping rice systems,we investigated the effects of a cultivation pattern of strong seedlings with increased planting density and reduced nitrogen application(SDN)on the morphological and physiological characteristics of double cropping *** results indicated that the effects of SDN on the morphological characteristics of the single plant roots of double cropping rice were not significant,but the morphological characteristics of the population roots were largely ***,SDN significantly increased the morphological indexes of the root population such as root fresh weight,root volume,root number,root length and root dry *** effects of SDN on the total root absorption areas and root active absorption areas of the single plants were non-significant,but it dramatically enhanced the total root absorption areas and root active absorption areas of the plant population during the tillering,heading and mature *** addition,SDN significantly increased the root bleeding intensity and elevated the soluble sugar and free amino acid contents of root bleeding *** to the traditional cultivation pattern(CK),SDN significantly increased root bleeding intensity at the heading stage by 4.37 and 8.90% for early and late rice,***,SDN profoundly enhanced the soluble sugar contents of root bleeding sap by 12.85 and 10.41% for early and late rice,*** addition,SDN also significantly enhanced free amino acid content of root bleeding sap by 43.25% for early rice and by 37.50% for late rice systems compared to ***,SDN increased the actual yield of double cropping rice mainly due to the higher effective panicle number and the larger seedsetting *** actual yields of early rice under SDN were higher than CK by 9.37 and 5.98% in 2016 and 2017,and the actual yields of late rice under SDN were higher than CK b

关键词： planting density nitrogen fertilizer double cropping rice root yield

Local magnetic moment oscillation around an Anderson impurity on graphene

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 192-201页

作者： Shuai li zhen Ma Jin-hua Gao School of Science Hebei University of Science and Technology School of Electronics and Information Zhengzhou University of Light Industry School of Physics and Wuhan National High Magnetic Field Center Huazhong University of Science and Technology

We theoretically investigate the spin resolved Friedel oscillation （FO） and quasiparticle interference （QPI） in graphene induced by an Anderson *** the impurity becomes magnetic,the resulted FO becomes spin dependent,which gives rise to a local magnetic moment oscillation with an envelop decaying as r-2in real space in the doping ***,at half filling,the electron density and local magnetic moment will not oscillate but decay as *** spin resolved FO has both sublattice and spin ***,the local magnetic moment decay at half filling only occurs at one sublattice of graphene,which is quite like the phenomenon observed in the STM experiment (***ález-Herrero et al.,Science 352,437 （2016）).We further give an analytic formula about such spin dependent FO based on the stationary phase ***,we study the interference of quasiparticles around the magnetic impurity by calculating the spin dependent Fourier-transformed local density of states （FT-LDOS）.Our work gives a comprehensive understanding about the local magnetic moment oscillation around an Anderson impurity on graphene.

关键词： Friedel oscillation local magnetic moment graphene Anderson impurity

In vitro study of safety and co-efficiency of the transbronchial coagulation techniques

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Chinese Medical Journal 2013年第1期126卷 124-128页

作者： BAI Chong DONG Yu-chao SONG Xiao-lian huANG Yi SHI hui hu zhen-li li Qiang Department of Respiratory Medicine Changhai Hospital SecondMilitary Medical University Shanghai 200433 China Department of-Respiratory Medicine Shanghai 10th People'sHospital Tongji University School of Medicine Shanghai 200072China

Background The usual transbronchial coagulation techniques include microwave, argon plasma coagulation （APC）, electrocautery and cryotherapy. However, there are serious clinical problems in the safety of each. By analyzing the experimental data and clinical observations, we observed the variable effects of different coagulation techniques via bronchofibroscopy, to look for an optimal interventional management of luminal bronchus diseases, and evaluate the safety and the equivalent point. Methods Four kinds of coagulation techniques under bronchoscopy were performed on the fresh bronchus of healthy sheep, and the pathologic changes in all groups were observed under the microscope. The different treatment parameters were as follows： microwave 60 Wxl second, 3 seconds, 5 seconds and 40 W×1 second, 3 seconds, 5 seconds; APC 40 W×1 second, 3 seconds, 5 seconds; electrocautery 40 W×1 second, 3 seconds, 5 seconds; cryotherapy 100 Ω×60 seconds, 120 seconds. Results After treatment, ovine bronchial mucosa in all groups showed pathologic changes such as local necrosis and amotio of the mucosa lining epithelium, local submucosa coagulative necrosis or tissue defects, while inflammation in the surrounding tissue was not obvious. Under the same output power and action time, different methods had different outcomes. The damage by APC was the most superficial, microwave was the second, and electrocautery caused the worst damage. The study also found that effects of electrocautery at 40 W×3 seconds, microwave at 40 W×5 seconds or 60 W×3 seconds, APC at 40 W×5 seconds and cryotherapy at 100 Ω×120 seconds were the equivalent point conditions. The appearance included mucosa absence, partial submucosa absence, and collagen fiber coagulation in treatment areas. Conclusions Each coagulation technique has its own characteristic. It is very important to choose the appropriate power and action time of the suitable method according to the therapy requirement.

关键词： bronchoscopy coagulation microwave argon plasma coagulation electrocautery cryotherapy

Enantioseparation of Racemic Anti-hepatitis New Drug Bicyclol with Crystallization

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Chinese Chemical Letters 2005年第11期 55-57页

作者： Wei hu, Yan li, Chun zhen ZHANG Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050

The enantioseparation of anti-hepatitis new drug (±)-bicyclol was performed by optically active alkaloid. The alcoholic acid, the hydrolysate of bicyclol was reacted with optically active alkaloid, such as brucine, strychnine, quinidine etc., the diastereoisomeric salts were obtained by fractional recrystallization, then separately decomposed and esterified to obtain the two enantiomers of bicyclol. The pharmacological study showed that the effect of (-)-bicyclol was more potent than racemic bicyclol two times and the potency of (+)-bicyclol was incative.

关键词： (±)-Bicyclol 4 4′-dimethoxy-2 3 2′ 3′-bis(methylenedioxy)-6-hydroxymethyl-6′- methoxy-carbonyl biphenyl anti-hepatitis resolution

《现代汉语词典》古词语释义偏误及应遵循的原则

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湘潭大学学报（哲学社会科学版） 2010年第2期34卷 148-151页

作者：胡丽珍湘潭大学文学与新闻学院湖南湘潭411105

《现代汉语词典》对古语词的释义存在详略偏误的问题,归纳起来有四种:一是上位概念越级,二是未释区别特征,三是未分总名与专名,四是不辨同义词。针对这些问题,我们提出了《现代汉语词典》古词语释义详略度应该掌握的三条原则,即:上位概... 详细信息

《现代汉语词典》对古语词的释义存在详略偏误的问题,归纳起来有四种:一是上位概念越级,二是未释区别特征,三是未分总名与专名,四是不辨同义词。针对这些问题,我们提出了《现代汉语词典》古词语释义详略度应该掌握的三条原则,即:上位概念准确的原则、解释名物词的区别特征的原则、兼顾系统平衡的原则。

关键词：现代汉语词典古词语浑释原则

煤层注液态CO_2压裂增透过程及裂隙扩展特征试验

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煤炭学报 2016年第11期41卷 2793-2799页

作者：文虎李珍宝王振平马砺郭英王旭西安科技大学西部矿井开采及灾害防治教育部重点实验室陕西西安710054 西安科技大学安全科学与工程学院陕西西安710054 兖矿集团有限公司山东邹城273515 兖州煤业股份有限公司南屯煤矿山东邹城273515

针对我国煤层＂高储低渗＂的赋存特征,基于液态CO_2黏度低、阻力小、酸化解堵及相变增压的特点,采用液态CO_2进行煤层压裂增透现场试验,研究煤层压裂过程裂隙扩展规律。结果表明：压裂过程流量随着压力的增长呈现出＂波动＂特性,钻孔周... 详细信息

针对我国煤层＂高储低渗＂的赋存特征,基于液态CO_2黏度低、阻力小、酸化解堵及相变增压的特点,采用液态CO_2进行煤层压裂增透现场试验,研究煤层压裂过程裂隙扩展规律。结果表明：压裂过程流量随着压力的增长呈现出＂波动＂特性,钻孔周围煤体受CO_2压力作用产生裂隙并向前延伸,压裂初期裂隙扩展速度较快,随后逐渐减小;压裂裂隙同时沿压裂孔轴向和径向扩展;压力及流量曲线在1.8,2.2 MPa处出现拐点,压裂过程分为3个阶段,各阶段煤体破坏形式依次为钻孔破碎区裂隙起裂—弱面扩展—微孔隙破坏。现场压裂试验结果表明压裂半径可达10~20 m,且与水力压裂相比在压裂安全性、时间和效果方面存在技术优势。

关键词：增透人工裂隙液态CO2 压裂半径扩展特征

热震作用下YSZ活性扩散障的非线性有限元分析

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稀有金属材料与工程 2016年第11期45卷 2851-2856页

作者：胡祯李争显刘林涛李江涛西安建筑科技大学陕西西安710055 西北有色金属研究院陕西西安710016 东北大学辽宁沈阳110819

采用有限元法研究,经历多次热震后,Ni Cr Al Y涂层/YSZ扩散障/RenéN5基体内应力分布及演变和波峰值对应力的影响。研究发现,75次热震后模型外边缘附近及氧化铝层中存在较高的剪切应力和拉应力,裂纹会在该处萌生及扩展。各处的应力值随... 详细信息

采用有限元法研究,经历多次热震后,Ni Cr Al Y涂层/YSZ扩散障/RenéN5基体内应力分布及演变和波峰值对应力的影响。研究发现,75次热震后模型外边缘附近及氧化铝层中存在较高的剪切应力和拉应力,裂纹会在该处萌生及扩展。各处的应力值随热震次数的增加均有所增大;随波峰峰值的增加,氧化铝层内的应力值变化最大,其中当波峰峰值(A)为3μm时,扩散障结构较优。

关键词： YSZ活性扩散障热震有限元分析

Photo‑Energized MoS_(2)/CNT Cathode for High‑Performance li–CO_(2)Batteries in a Wide‑Temperature Range

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Nano-Micro Letters 2025年第1期17卷 160-175页

作者： Tingsong hu Wenyi lian Kang hu Qiuju li Xueliang Cui Tengyu Yao Laifa Shen Jiangsu Key Laboratory of Materials and Technologies for Energy Storage College of Materials Science and TechnologyNanjing University of Aeronautics and AstronauticsNanjing 210016People’s Republic of China

li–CO_(2) batteries are considered promising energy storage systems in extreme environments such as Mars;however,severe performance degradation will occur at a subzero temperature owning to the sluggish reaction ***,a photo-energized strategy adopting sustainable solar energy in wide working temperature range li–CO_(2) battery was achieved with a binder-free MoS_(2)/carbon nanotube(CNT)photo-electrode as *** unique layered structure and excellent photoelectric properties of MoS_(2) facilitate the abundant generation and rapid transfer of photo-excited carriers,which accelerate the CO_(2) reduction and li_(2)CO_(3) decomposition upon *** illuminated battery at room temperature exhibited high discharge voltage of 2.95 V and mitigated charge voltage of 3.27 V,attaining superior energy efficiency of 90.2%and excellent cycling stability of over 120 *** at an extremely low temperature of−30℃,the battery with same electrolyte can still deliver a small polarization of 0.45 V by the photoelectric and photothermal synergistic mechanism of MoS_(2)/CNT *** work demonstrates the promising potential of the photo-energized wide working temperature range li–CO_(2) battery in addressing the obstacle of charge overpotential and energy efficiency.

关键词： li-CO_(2)batteries Photo-energized Wide operation-temperature Kinetics MoS_(2)