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公元241~1912年中国河西走廊地区年际干湿变化与游牧战争的关系

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中国科学：地球科学 2024年第6期54卷 1950-1959页

作者：唐飞史志林田沁花杜小刚张永中国科学院地理科学与资源研究所陆地表层格局与模拟院重点实验室北京100101 兰州大学敦煌学研究所兰州730020 中国气象局国家气候中心北京100081 甘肃祁连山国家级自然保护区管护中心隆畅河自然保护站张掖734400 中国科学院大学北京100049

长期以来,气候与战争之间的关系一直是一个备受关注的科学和社会问题.在本研究中,探讨了公元241年以来中国河西走廊地区气候与战争爆发的可能关联.基于河西走廊地区树轮资料以及历史时期游牧战争数据,利用时序叠加分析方法,我们发现河... 详细信息

长期以来,气候与战争之间的关系一直是一个备受关注的科学和社会问题.在本研究中,探讨了公元241年以来中国河西走廊地区气候与战争爆发的可能关联.基于河西走廊地区树轮资料以及历史时期游牧战争数据,利用时序叠加分析方法,我们发现河西走廊地区年际干湿变化与游牧民族发动的战争之间存在明显的相关性,但是这种关系是动态的,并与该地区的政权格局有关.在河西走廊存在多个地方政权统治的时期,战争往往随着干旱的气候条件而发生,这可能是由于这些时期的异常干旱加剧了对资源和土地的争夺.相反,在统一王朝管理时期,气候湿润时更容易发生战争,因为牧场的扩大和资源的积累有助于游牧民族的对外征服.这些发现凸显了战争与气候变化之间关系的复杂性.为了更加全面地分析二者之间的关系,需要在更多地区建立覆盖范围更广、分布更均匀且连续的高分辨率历史温湿数据集.此外,对于具有独特特征的区域,需要收集更多的历史战争数据,进行分类讨论研究.

关键词：干旱年际干湿变化战争河西走廊树轮游牧民族

The Reaction of Benzimidazole Methiodide Salt with Bis-Grignard Reagent

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Chinese Chemical Letters 1997年第6期8卷 465-466页

作者： shi, z Gu, H NW UNIV XIAN DEPT CHEMXIAN 710069PEOPLES R CHINA

The reaction of benzimidazole methoidide salt with bis-Grignard reagent is reported, and a new method for the preparation of dialdehyde is provided.

关键词： The Reaction of Benzimidazole Methiodide Salt with Bis-Grignard Reagent

Opportunities and challenges of biodegradable zn-based alloys

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Journal of Materials Science & Technology 2020年第11期42卷 136-138页

作者： H.F.Li z.z.shi L.N.Wang Beijing Advanced Innovation Center for Materials Genome Engineering School of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijing100083China

Following the footsteps of biodegradable Mg-based and Fe-based alloys,biodegradable zn-based alloy is a newcomer and rising star in the family of biodegradable metals and *** combined superior mechanical properties,appropriate degradation rates,excellent biocompatibility of biodegradable zn-based alloys have brought worldwide research interest on the design,development and clinical translation of zn-based *** present perspective has summarized opportunities and challenges in the development of biodegradable zn-based alloys.

关键词： Biodegradable zn-based alloys Clinical applications Mechanical properties Degradation behavior Biocompatibility Corrosion fatigue Bio-tribocorrosion

The synthesis of dialdehydes from dicarboxylic acids via imidazolines

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Chinese Science Bulletin 1997年第2期42卷 130-132页

作者： shi, z Gu, H Xu, LL Department of Chemistry Northwest University Xi’an China

DIALDEHYDES are important chemical industrial materials, which are widely used in textile,medicine, dye, binder, coating and so on. The traditional method for preparing dialdehydes is the catalytic oxidation of glycol. We have reported the reduction ring-opening reaction of inndazoline by NaBH4.In this note, the reduction of imidazoline by sodium and ethanol is studied. A new synthetic method for the preparation of dialdehydes from dicarboxylic acids

关键词： dicarboxylic acid imidazoline dialdehyde new synthetic method.

Professor zhao-Yin Wang,Ph.D.,*** Editor-in-Chief of the International Journal of Sediment Research

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International Journal of Sediment Research 2014年第1期29卷 133-134页

作者： John z.shi Hong-Wei Fang Shanghai Jiao Tong University Tsinghua University

(January 1998-December 2013)Current developments in sediment research continue at a heady pace,and are reported in the International Journal of Sediment Research(IJSR)at about 500 pages per ***,as of January 2014,a major change has occurred:after16 years(January 1998 to December 2013)as Editor-in-Chief,Professor zhao-Yin Wang has stepped down from the handling of manuscripts.

关键词： Wang M.ASCE Editor-in-Chief of the International Journal of Sediment Research Professor zhao-Yin Wang,Ph.D

The Synthesis of Dialdehyde from Sodium Hydrogen Telluride with 1,1',3,3'-Tetramethyl-2,2'-bis-benzimidazolium Salt

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Chinese Chemical Letters 2002年第9期13卷 836-838页

作者： Yue K.F. Gu H. shi z. Department of Chemistry Northwest University Xi'an 710069 China

The reaction of bis-benzimidazolium salts with sodium hydrogen telluride is reported, and a new synthetic method for dialdehydes is provided.

关键词： Bis-benzimidazolium salt sodium hydrogen telluride dialdehyde synthesis.

WAVE RESISTANCE OF WAVE-PIERCING CATAMARANS

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Journal of Hydrodynamics 2000年第4期12卷 88-98页

作者： Lu, X.P. Huang, Y. shi, z.K. Coll. of Traffic Sci. and Eng. Huazhong Univ. of Sci. and Technol. Wuhan 430074 China

Present paper researches the theoretical method for calculating the wave resistance of wave-piercing catamaran. As an example the wave resistance of a wave-piercing catamaran is calculated. The comparison among the theoretical calculation results, the model test results and the graphic evaluation results shows the efficiency of present theoretical method. Finally the wave resistance regulation of wave-piercing catamarans is investigated based on the theoretical method.

关键词： ships

Study of the mechanisms of acupuncture and moxibustion treatmentfor ulcerative colitis ratsinview of the gene expression of cytokines

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World Journal of Gastroenterology 1999年第6期5卷 515-517页

作者： Wu HG zhou LB Pan YY Huang C Chen HP shi z Hua XG Shanghai Inst Acupuncture Moxibust & Meridians Shanghai 200030 Peoples R China

AIM:To observe the effect of acupuncture and moxibustion on the expression of IL-1beta and IL-6 mRNA in ulcerative colitis ***:The SD rat ulcerative colitis model was created by immunological method associated with local stimulation. Colonic mucosa was prepared from human fresh surgical colonic specimens, homogenized by adding appropriate amount of normal saline and centrifuged at 3000r/min. The supernatant was collected for measurement of protein conentration and then mixed with Freund adjuvant. This antigen fluid was first injected into the plantae of the model group rats, and then into their plantae, dorsa, inguina and abdominal cavities (noFreund adjuvant for the last injection) again on the 10th, 17th, 24th and 31st day. When a certain titer of serum anti colonic antibody was reached, 2% formalin and antigen fluid (no Freund adjuvant) were administered separately by enema. The ulcerative colitis rat model was thus set up. The animals were randomly divided into four groups: model control group (MC, n = 8), electro acupuncture group (EA, n = 8), herbs partition moxibustion group (HPM 8), normal control group (NC,n = 8). HPM: Moxa cones made of refined mugwort floss were placed on the medicinal pad (medicinal pad dispensing: Radix Aconiti praeparata, cortex Cinnamomi, etc) for Qihai (RN 6) and Tianshu (ST 25, bilateral) and ignited. Two moxa cones were used for each acupoint once a day and 14 times in all. EA: Tianshu (bilateral) and Qihai were stimulated by the intermittent pulse with 2Hz frequency, 4mA intensity for 20 minutes once a day and 14 times in all. After treatment, rats of all four groups were killed simultaneously. The spleen was separated and the distal colon was dissected. Total tissue RNA was isolated by the guanidinium thiocyanate phenol chloroform extraction method. RT-PCR technique was used to study the expression of IL-1 beta and IL-6 ***:IL-1 beta and IL-6 mRNAs were not detected in the spleen and colonic mucosa of the NC rat

关键词： colitis, ulcerative/therapy acupuncture and moxibustion therapy gene expression cytokines interleukin-1 beta interleukin-6

Crack Initiation Mechanism of z3CN20.09M Duplex Stainless Steel during Corrosion Fatigue in Water and Air at 290 °C

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Journal of Materials Science & Technology 2015年第11期31卷 1144-1150页

作者： H.C.Wu B.Yang Y.z.shi Q.Gao Y.Q.Wang State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Collaborative Innovation Center of Universal Iron & Steel Technology School of Materials Science and Engineering Anhui University of Technology

The crack initiation mechanism of a z3CN20.09M duplex stainless steel （DSS） during corrosion fatigue （CF） in water and air at 290 ℃ was investigated by using a CF cracking machine and a scanning electron microscopy （SEM）. The cracks were initiated successively at the persistent stip bands （PSBs）, phase boundaries （PBs） and pitting corrosion points （PCPs） of the specimens when they were tested in water at 290 ℃, while in airat 290 ℃ the cracks were only initiated at the PSBs and PBs. And the cracks were found mainly to initiate at the PSBs and PBs when the specimens were tested in water and air at 290 ℃, respectively. The results also reveal that the cracks were likely to be initiated at the first 20% of fatigue life of the specimens tested in water at 290 ℃. However, the cracks were not found until 50% of fatigue life when tested in air at 290 ℃. Moreover, the crack numbers of the specimens tested in water at 290 ℃ were much more than those tested in air at 290 ℃.

关键词： Duplex stainless steel Corrosion fatigue Crack initiation High temperature water