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SYNTHESIS AND CRYSTAL STRUCTURE OF A NEW COMPOUND Sr_6Sn_2Nb_8O_30 被引量:1
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作者 FANG Liang ZHANG Hui WU Bolin YUAN Runzhang Wuhan University of Technology 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 1999年第2期35-39,共5页
A new compound Sr6Sn2Nb8O30 was found in the ternary system of SrO-SnO2-Nb2O5. The transparent colorless crystal with needle-like shape can be grown by flux method. The crystal structure of new compound was determined... A new compound Sr6Sn2Nb8O30 was found in the ternary system of SrO-SnO2-Nb2O5. The transparent colorless crystal with needle-like shape can be grown by flux method. The crystal structure of new compound was determined by X-ray diffraction, and its belongs to tungsten bronze structure. Sr6Sn2Nb8O30 crystallizes in orthorhombic system with unit cell parameters a= 17. 579 (DA,6= 17. 509(DA,c=7. 7880(5)A,Z = 4 and space group Cmm2. 展开更多
关键词 Sr_6Sn_2Nb_8O_30 system new compound tungsten bronze structure
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A New Compound from Dalbergia odorifera T. Chen 被引量:1
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《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第11期993-994,共2页
关键词 CHEN A new compound from Dalbergia odorifera T
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NEW COMPOUNDS FROM PEUCEDANUM PRAERUPTORUM 被引量:2
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作者 Ling Yi KONG Yue Hu PEI +1 位作者 Xian LI Ting Ru ZHU 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第1期37-38,共2页
Four new compounds named qianhucoumarins E,F,G and baihuaqianhuoside have been isolated from the root of Peucedanum praeruptorum.Their structures were elucidated by chemical evidences and spectral analysis.
关键词 new compoundS FROM PEUCEDANUM PRAERUPTORUM
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SYNTHESIS AND X-RAY POWDER STUDY OF A NEW COMPOUND:Ba_6Ti_7Nb_9O_(42)
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作者 方亮 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 1998年第4期42-44,共3页
A new compound Ba6Ti7Nb9O42 was prepared for the first time by solid state reaction in BaO-TiO2-Nb2O5, ternary system. The X-ray powder diffraction data of the title compound was determined. Ba6Ti7Nb9O42 crystallizes ... A new compound Ba6Ti7Nb9O42 was prepared for the first time by solid state reaction in BaO-TiO2-Nb2O5, ternary system. The X-ray powder diffraction data of the title compound was determined. Ba6Ti7Nb9O42 crystallizes in the hexagonal system -with unit cell parameters a=9.0527(4) A,c=11.790(1) A,and space group P63/mcm(193),z=1. The calculated and measured densities are 5. 293 g/cm3 and 5.285 g/cm3, respectively. 展开更多
关键词 BaO-TiO2-Nb2O5 system new compound X-RAY powder diffraction
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A New Compound with C_2-Symmetry 3R,3'R-Dihydroxy-6,6',6,6'-tetramethyl-2R,2'R,-bis-4H-pyran
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作者 Li Bing Yu Li XU and Zhi Qin WANG(Shanghai Institute of Organic Chemistry. Chinese Acadmey of Sciences 354 Fenglin Road. Shanghai 200032) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第8期653-654,共2页
The title compound 1 was synthesized from 1.2:5,6-dianhydro-3,4-dianhydro-3,4-isopropylideneD-mannitol 2 through four steps in a total yield of 53%. The absolute configuration of this compound was confirmed by X-ray d... The title compound 1 was synthesized from 1.2:5,6-dianhydro-3,4-dianhydro-3,4-isopropylideneD-mannitol 2 through four steps in a total yield of 53%. The absolute configuration of this compound was confirmed by X-ray diffraction. 展开更多
关键词 tetramethyl-2R 2’R REV CL bis-4H-pyran A new compound with C2-Symmetry 3R 3’R-Dihydroxy-6 6
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Lactariolide,a New 14-Membered-Ring Compound from Lactarius Subvellereus 被引量:3
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作者 Jing ZHANG Xiao Zhang FENG(Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100050) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第2期135-136,共2页
Lactariolide (I), a new 14-membered-ring lactone was isolated from the fruit bodies of Lactarius subvellereus (Russulaceae), and its structure was elucidated as (R)-13-hydroxy-trans-9, 11-octadecadienoic acid lactone ... Lactariolide (I), a new 14-membered-ring lactone was isolated from the fruit bodies of Lactarius subvellereus (Russulaceae), and its structure was elucidated as (R)-13-hydroxy-trans-9, 11-octadecadienoic acid lactone by means of physical and spectral data. 展开更多
关键词 CL Lactariolide a new 14-Membered-Ring compound from Lactarius Subvellereus
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NEW MACROCYCLIC COMPOUND,CLEMOCHINENOSIDE B FROM CLEMATIS CHINENSIS 被引量:1
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作者 Chun Qing SONG Ren Sheng XU State Key Laboratory for New Drug Research,Shanghai Institute of Materia Medica,Academia Sinica,319 Yueyang Rd,Shanghai 200031 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第6期505-506,共2页
The structure of a new macrocyclic compound,clemochinenoside B, isolated from the root of Clematis chinensis was elucidated by means of NMR,FAB-MS,NOE and chemical hydrolysis.
关键词 NOE new MACROCYCLIC compound CLEMOCHINENOSIDE B FROM CLEMATIS CHINENSIS
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Gapped Spin-1/2 Spinon Excitations in a New Kagome Quantum Spin Liquid Compound Cu_3Zn(OH)_6FBr 被引量:2
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作者 冯子力 李政 +14 位作者 孟鑫 衣玮 魏源 张骏 王艳成 蒋伟 刘峥 李世燕 刘锋 雒建林 李世亮 郑国庆 孟子杨 梅佳伟 石友国 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第7期249-253,共5页
We report a new kagome quantum spin liquid candidate CuaZn(OH)6FBr, which does not experience any phase transition down to 50inK, more than three orders lower than the antiferromagnetic Curie-Weiss temperature (-20... We report a new kagome quantum spin liquid candidate CuaZn(OH)6FBr, which does not experience any phase transition down to 50inK, more than three orders lower than the antiferromagnetic Curie-Weiss temperature (-200 K). A clear gap opening at low temperature is observed in the uniform spin susceptibility obtained from 19F nuclear magnetic resonance measurements. We observe the characteristic magnetic field dependence of the gap as expected for fractionalized spin-1/2 spinon excitations. Our experimental results provide firm evidence for spin fractionalization in a topologically ordered spin system, resembling charge fraetionalization in the fractional quantum Hall state. 展开更多
关键词 OH Gapped Spin-1/2 Spinon Excitations in a new Kagome Quantum Spin Liquid compound Cu3Zn Cu
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A New Reagent for the Reduction of Aromatic Nitro Compounds 被引量:1
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作者 Jian Guo SHAO Long Cheng WANG +1 位作者 Ming ZHENG Qi ZHONG(Medical and Pharmaceutical Research Centre, Chemistry Department of Teachers College, Yangzhou University, Yangzhou, 225002) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第8期683-684,共2页
Aromatic nitro compounds were reduced to the corresponding anilines by refluxing with potassium selenated borohydride (KBH2Se3) prepared from potassium borohydride and selenium in refluxed formamide.
关键词 A new Reagent for the Reduction of Aromatic Nitro compounds
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A NEW TYPE OF CHAIN COMPOUND,STRUCTURE OF TA_4(TE_2)_4TE_4I
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作者 Shui Quan DENG Hong Hui ZHUANG Ding Ming WU Jin Ling BUANG Fujian Institute of Research on the Structure of Matter,Chinese Academy of Sciences and State Key Laboratory of Structure Chemistry,Fuzhou,Fujian 350002 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第3期273-274,共2页
Ta_4(Te_2)_4Te_4I,Mr=2381.90,Monoclinic,C2/c,a=21.987(2),b=6.153(2),c= 19.936(3),β=122.42(14),V=2276.7 ~3,z=4,Dm=6.8(5)g/cm^3,Dc=6.95g/cm^3,λ(Mok)= 0.71073,μ=354.0cm^(-1),F(000)=3876,T=296(1)k,R=5.3%,Rw=6.8%,for 11... Ta_4(Te_2)_4Te_4I,Mr=2381.90,Monoclinic,C2/c,a=21.987(2),b=6.153(2),c= 19.936(3),β=122.42(14),V=2276.7 ~3,z=4,Dm=6.8(5)g/cm^3,Dc=6.95g/cm^3,λ(Mok)= 0.71073,μ=354.0cm^(-1),F(000)=3876,T=296(1)k,R=5.3%,Rw=6.8%,for 1118 unique observed reflections(1>3σ(Ⅰ)).The structure is composed of [Ta_4(Te_2)_4Te_4I]_∞~ chains,which are formed by the four-nuclear butterfly cluster units "Ta_4(Te_2)_4Te_4" with the Ⅰ atoms as the bridging atoms between different cluster units. 展开更多
关键词 TA TE A new TYPE OF CHAIN compound STRUCTURE OF TA4 TE2
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A NEW ARTIFICIAL PHOTOSYNTHESIS COMPOUND FOR PHOTOELECTRIC CONVERSION
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作者 Xiang Dong WANG Bao Wen ZHANG Jian Wei BAI Yi CAO Xu Rui XIAO Jing Mei XU Institute of Photographic Chemistry,Academia Sinica,Beijing,100101 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第4期281-284,共4页
A new triad model compound porphyrin-viologen-carbazole was synthesized to mimic photosynthesis.A mechanism including photoinduced electron transfer and two-step charge separation was suggested.This triad compound was... A new triad model compound porphyrin-viologen-carbazole was synthesized to mimic photosynthesis.A mechanism including photoinduced electron transfer and two-step charge separation was suggested.This triad compound was easy to form LB film and rather high photodriven voltage and current were obtained with only one layer of LB film On the surface of SnO_2 conductive glass. 展开更多
关键词 A new ARTIFICIAL PHOTOSYNTHESIS compound FOR PHOTOELECTRIC CONVERSION
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STUDY ON SYNTHESIS,CHARACTERIZATION AND STRUCTURE OF A NEW RARE EARTH COORDINATION COMPOUND WITH BENZOIC ACID
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作者 段治邦 金钟声 +1 位作者 胡宁海 倪嘉缵 《Journal of Rare Earths》 SCIE EI CAS CSCD 1990年第2期81-86,共6页
In this paper,a new rare earth benzoate coordination compound,[TbL_3(HL)(H_2O)]_2 (HL=C_7H_6O_2=benzoic acid) is synthesized and characterized by elemental analysis DTA,TG,DTC,and IR spectra.The title compound crystal... In this paper,a new rare earth benzoate coordination compound,[TbL_3(HL)(H_2O)]_2 (HL=C_7H_6O_2=benzoic acid) is synthesized and characterized by elemental analysis DTA,TG,DTC,and IR spectra.The title compound crystallizes in triclinic,space.group P with a=9.148(1),b=11.460(2), c=13.506(2);α=112.76(1),β=91.83(1),γ=91.99(1)°;Z=1;V=1303.3.The final R factor is 0.0235.The rare earth ion is nine-coordinated to form a distorted monocapped square antiprism. 展开更多
关键词 STUDY ON SYNTHESIS CHARACTERIZATION AND STRUCTURE OF A new RARE EARTH COORDINATION compound WITH BENZOIC ACID
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STUDIES ON ORGANOPHOSPHORUS COMPOUNDS 86 SOME NEW ASPECTS ON THE SYNTHESIS OF DIALKYL 1-ISOCYANO-BENZYL-AND/OR ALKYL-PHOSPHONATES
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作者 Cheng Ye YUAN Wei Sheng HUANG Zhi Bin YUAN Shanghai Institute of Organic Chemistry,Chinese Academy of Science,345 Lingling Lu,Shanghai,200032 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第12期1047-1050,共4页
1-Isocyano substituted benzylphosphonates were prepared by dehydration of 1-N-formylamino substituted benzylphosphonates,which were obtained by a tricomponental condensation described by us.Mean- while addition of die... 1-Isocyano substituted benzylphosphonates were prepared by dehydration of 1-N-formylamino substituted benzylphosphonates,which were obtained by a tricomponental condensation described by us.Mean- while addition of diethyl phosphite to N-trityl aldimine followed by deprotection,formylation and dehydration gave corresponding 1-isocyano alkylphosphonates in one-pot procedure. 展开更多
关键词 STUDIES ON ORGANOPHOSPHORUS compoundS 86 SOME new ASPECTS ON THE SYNTHESIS OF DIALKYL 1-ISOCYANO-BENZYL-AND/OR ALKYL-PHOSPHONATES
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A NEW METHOD FOR SYNTHESIS OF O-ISOPROPYL SUBSTITUTED AROMATIC COMPOUNDS
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作者 Xue Chao WANG Xin Fu PANState Key Laboratory of Applied Organic Chemistry,Lanzhou University,Lanzhou,730000 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第5期329-332,共4页
Heteroatom-directed aromatic lithiation reactions used for the regiospecific synthesis of o-isopropyl substituted phenolic and benzyl alcoholic compounds are described.
关键词 A new METHOD FOR SYNTHESIS OF O-ISOPROPYL SUBSTITUTED AROMATIC compoundS
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A Cognitive Study of Word-formation of Chinese New Metaphorical Compounds
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作者 王晓晖 《海外英语》 2012年第5X期262-263,共2页
A great deal of new words are emerging and coming into vogue.Most of the previous studies on Chinese new words focused on their classification,form and meaning,as well as the social motivations.This thesis chooses to ... A great deal of new words are emerging and coming into vogue.Most of the previous studies on Chinese new words focused on their classification,form and meaning,as well as the social motivations.This thesis chooses to study the concept metaphor of Chinese new metaphorical compounds from the cognitive perspective based on 396 new words in 2010 and aims to classify the new metaphorical words in a new way and pay attention to the analysis of word formation of new metaphorical compounds.Besides,this paper attempts to explore the understanding process of metaphorical new words. 展开更多
关键词 CHINESE new words compoundS METAPHOR WORD formatio
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A New Method for the Preparation of Substituted Benzil Compounds from Substituted Benzoin Compounds
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《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 1999年第S1期321-321,共1页
关键词 A new Method for the Preparation of Substituted Benzil compounds from Substituted Benzoin compounds
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THE NEW MODEL FOR CALCULATION OF STANDARD ENTROPIES OF SOLID COMPOUNDS Ⅲ CALCULATION FOR STANDARD ENTROPIES OF SOLID BINARY OXIDES
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作者 Xun Min YU Yuan Li ZHAO Dao Wu YANG (Jingzhou Educalional College Hubei. 414100) 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第5期405-406,共2页
This paper establishes a new model for calculation of the standard entropies of solid binary oxides as follows: S_(29)=27.07×Φ_1+1.120×Φ_2+n_1×k×Φ, -22.19 e.u (R=0.9960) We have invesigated 103 ... This paper establishes a new model for calculation of the standard entropies of solid binary oxides as follows: S_(29)=27.07×Φ_1+1.120×Φ_2+n_1×k×Φ, -22.19 e.u (R=0.9960) We have invesigated 103 binary oxides. and found good agreemenl between estimated and experimental entropies. 展开更多
关键词 CALCULATION FOR STANDARD ENTROPIES OF SOLID BINARY OXIDES THE new MODEL FOR CALCULATION OF STANDARD ENTROPIES OF SOLID compoundS
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新文科背景下复合型人才培养实践模式研究 被引量:2
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作者 崔延强 林笑夷 段禹 《苏州大学学报(教育科学版)》 北大核心 2024年第1期58-67,共10页
新文科建设背景下,各高校在跨学科、跨专业的复合型人才培养方面积极进行改革和创新尝试,形成了诸多值得借鉴的典型模式。通过对全国数十所高校新文科建设中复合型人才培养情况进行总结和分析,研究将现有人才培养模式归纳为双学位和联... 新文科建设背景下,各高校在跨学科、跨专业的复合型人才培养方面积极进行改革和创新尝试,形成了诸多值得借鉴的典型模式。通过对全国数十所高校新文科建设中复合型人才培养情况进行总结和分析,研究将现有人才培养模式归纳为双学位和联合学位模式、微专业模式、文科实验室模式、书院模式。这四种典型模式各有优势,用新视角、新范式、新方法带动了传统文科转型升级。未来,各高校应继续探索建立以立德树人为目标、以优势学科为核心、以学科交叉为抓手、以名家大师为引领的复合型文科人才培养体系。 展开更多
关键词 新文科 复合型人才培养 高校 实践模式 路径
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新文科下商科人才培养:时代要求与路径选择
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作者 陈晓芳 陈昕 +1 位作者 洪荭 夏文蕾 《天津大学学报(社会科学版)》 2024年第3期241-249,共9页
剖析新文科建设的时代要求和企业招聘对人才的需求,提出集育人育才指导思想、四项能力培养目标、四大单元培养内容、文科中国化培养特色于一体的新商科复合型卓越人才培养框架。探索人才培养体系中专业、课程、教材同频共振的全要素改革... 剖析新文科建设的时代要求和企业招聘对人才的需求,提出集育人育才指导思想、四项能力培养目标、四大单元培养内容、文科中国化培养特色于一体的新商科复合型卓越人才培养框架。探索人才培养体系中专业、课程、教材同频共振的全要素改革,学生、学术、学科层层递进的全链条衔接,以及教育、教师、教学自上而下的全流程驱动路径,力图打造我国理工类高校新文科建设亮点,为中国特色文科人才培养体系提供经验借鉴。 展开更多
关键词 新文科 新商科 复合型卓越人才 人才培养框架 培养路径
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金钗石斛中一个新的木防己毒烷型倍半萜
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作者 杜国鑫 蔡彩虹 +4 位作者 夏益华 黄圣卓 梅文莉 戴好富 陈惠琴 《热带亚热带植物学报》 CAS CSCD 北大核心 2024年第3期446-450,共5页
为了解金钗石斛乙醇提取物正丁醇部位的化学成分,通过硅胶、凝胶、反相硅胶和高效液相等各种色谱技术进行分离纯化得到3个化合物,并根据核磁共振、质谱等波谱手段确定其结构分别为2,11-epoxy-11,13-dihydroxypicrotoxano-3(15)-lactone ... 为了解金钗石斛乙醇提取物正丁醇部位的化学成分,通过硅胶、凝胶、反相硅胶和高效液相等各种色谱技术进行分离纯化得到3个化合物,并根据核磁共振、质谱等波谱手段确定其结构分别为2,11-epoxy-11,13-dihydroxypicrotoxano-3(15)-lactone (1)、2,4,6-三甲氧基苯-1-O-β-D-葡萄糖苷(2)和3-methylbutan-1-ol β-D-glucopyranoside (3)。其中化合物1是一个新的木防己毒烷型倍半萜,该类化合物是金钗石斛中具有代表性的倍半萜类型。所有化合物均没有α-葡萄糖苷酶和酪氨酸酶抑制活性,同时化合物1也没有神经保护活性。 展开更多
关键词 金钗石斛 化学成分 倍半萜 新化合物
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