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Asymmetric Conjugate Addition of Alcohols to (R)-(-)-5-[(1R,2S,5R)-Menthyloxy]-2-(5H)-furanone

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Chinese Chemical Letters 1997年第5期8卷 365-366页

作者： fu An kang Hong Yi yin and cheng lie yin(Departmenl of Chemistry, Beijing Normal Uviiversity, Beijing 100875) BEIJING NORMAL UNIV DEPT CHEMBEIJING 100875PEOPLES R CHINA

A series of enantiomencally pure (4R,5R)-(-)-4-alkryloxy-5-[(1R,2dihydro-2(5H)-furanones (2) have been synthesized in excellent yields via asymmetric conjugateadditions of primary alcohols to (R)-(-)-5-[(1R,2S,5R)-menthyloxy]-2(5H)-furanone (1) in the presenceof a catalytic amount of sodium in DMF, which provides access to new multifunctional homochiralbuilding blocks, optically. pure (R) or (S)-2-alkyloxy- 1,4-butanediols (3).

关键词： HNMR IR Menthyloxy cm KBr De furanone Asymmetric Conjugate Addition of Alcohols to

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水分含量对杂交臂形草青贮品质的影响

饲料研究 2024年第9期47卷 118-121页

作者：唐云会鲁茸格列周宇斌尹亚敏罗富成云南农业大学动物科学技术学院云南昆明650201 云南农业大学水利学院云南昆明650201

试验旨在探究不同水分含量对杂交臂形草(Brachiaria hybrid)青贮品质的影响。试验以莫拉特Ⅱ杂交臂形草为青贮原料,设置35.0%、45.0%、55.0%、65.0%和70.4%(CK)5个含水量水平,进行青贮试验,常温条件下贮存60 d,开封后取样检测其青贮品... 详细信息

试验旨在探究不同水分含量对杂交臂形草(Brachiaria hybrid)青贮品质的影响。试验以莫拉特Ⅱ杂交臂形草为青贮原料,设置35.0%、45.0%、55.0%、65.0%和70.4%(CK)5个含水量水平,进行青贮试验,常温条件下贮存60 d,开封后取样检测其青贮品质和营养品质。结果显示:随着青贮原料含水量的下降,青贮饲料的pH值、感官品质、粗脂肪、粗蛋白、粗灰分和可溶性碳水化合物含量均总体呈现先上升后下降的趋势,中性洗涤纤维含量总体呈现上升趋势,酸性洗涤纤维含量呈现逐渐降低的趋势。与CK相比,各处理组青贮饲料的氨态氮/总氮(NH3-N/TN)及丙酸、丁酸的含量显著降低(P<0.05),乳酸、乙酸和粗蛋白的含量显著增加(P<0.05)。原料含水量为45.0%~55.0%时,青贮饲料的pH值为4.08~4.10,感官品质最佳,为1级优等青贮饲料。研究表明,原料含水量对青贮饲料常规营养成分含量有一定影响,影响较大的指标是粗蛋白和粗脂肪含量,建议莫拉特Ⅱ杂交臂形草青贮原料的含水量应控制在45.0%~55.0%之间。

关键词：杂交臂形草原料含水量青贮pH值感官品质发酵品质

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Asymmetric 1,3-Dipolar Cycloaddition of the Chiral Nitronic Esters with Acrylate

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Chinese Chemical Letters 1997年第12期8卷 0-0页

作者： fu An kang and cheng lie Ym(Department of Chemiscy Beijtw Normal Unthersho Beijing 100875) Department of Chemistry Beijing Normal University Beijing 100875 China

Asymmetric 1,3-dipolar cycloaddihon of the chiral nitronic esters with acrylate giving the enantiomerically pure novel chiral bisheterocyclic compounds is describcd

关键词： Asymmetric 1 3-Dipolar Cycloaddition of the Chiral Nitronic Esters with Acrylate

Gastrointestinal manifestations of critical ill heatstroke patients and their associations with outcomes:A multicentre,retrospective,observational study

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World Journal of Gastroenterology 2024年第4期30卷 346-366页

作者： Yu-Cong Wang Xin-Yang Jin Zheng Lei Xiao-Jiao Liu Yu Liu Bang-Guo Zhang Jian Gong lie-Tao Wang Lv-Yuan Shi Ding-Yuan Wan Xin fu Lu-Ping Wang Ai-Jia Ma Yi-Song cheng Jing Yang Min He Xiao-Dong Jin Yan kang Bo Wang Zhong-Wei Zhang Qin Wu Department of Critical Care Medicine West China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina School of Pharmacy Macao University of Science and TechnologyMacao 999078China Department of Critical Care Medicine The First People's Hospital of Ziyang CityZiyang 641399Sichuan ProvinceChina Department of Critical Care Medicine The First People's Hospital of Guanghan CityChengdu 618399Sichuan ProvinceChina Department of Critical Care Medicine Lezhi County Traditional Chinese Medicine HospitalChengdu 641599Sichuan ProvinceChina Department of Critical Care Medicine Chengdu Qingbaijiang District People's HospitalChengdu 610399Sichuan ProvinceChina Department of Critical Care Medicine Ziyang People's HospitalChengdu 641399Sichuan ProvinceChina

BACKGROUND Extreme heat exposure is a growing health problem,and the effects of heat on the gastrointestinal(GI)tract is *** study aimed to assess the incidence of GI symptoms associated with heatstroke and its impact on *** To assess the incidence of GI symptoms associated with heatstroke and its impact on *** Patients admitted to the intensive care unit(ICU)due to heatstroke were included from 83 *** history,laboratory results,and clinically relevant outcomes were recorded at ICU admission and daily until up to day 15,ICU discharge,or *** symptoms,including nausea/vomiting,diarrhoea,flatulence,and bloody stools,were *** characteristics of patients with heatstroke concomitant with GI symptoms were *** regression analyses were performed to determine significant predictors of GI *** A total of 713 patients were included in the final analysis,of whom 132(18.5%)patients had at least one GI symptom during their ICU stay,while 26(3.6%)suffered from more than one *** with GI symptoms had a significantly higher ICU stay compared with those *** mortality of patients who had two or more GI symptoms simultaneously was significantly higher than that in those with one GI *** logistic regression analysis revealed that older patients with a lower GCS score on admission were more likely to experience GI *** The GI manifestations of heatstroke are common and appear to impact clinically relevant hospitalization outcomes.

关键词： Extreme heat Flatulence Sunstroke Intensive care units Diarrhea

Hydrocarbon generation history constrained by thermal history and hydrocarbon generation kinetics:A case study of the Dongpu Depression,Bohai Bay Basin,China

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Petroleum Science 2022年第2期19卷 472-485页

作者： Mei-Hua Yang yin-Hui Zuo kang-Nan Yan Yong-Shui Zhou Yun-Xian Zhang cheng-fu Zhang State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of TechnologyChengduSichuan 610059China Energy&Geoscience Institute University of UtahSalt Lake CityUT84108USA Research Institute of Exploration and Development Zhongyuan OilfieldSINOPECPuyangHenan 457001China

With the increasing exploration and development of typical hydrocarbon-rich depressions,such as the Dongpu Depression,the exploitation difficulty of shallow formations is *** is an urgent need to clarify the hydrocarbon generation mode and hydrocarbon generation histories in deep *** this study,a gold tube-autoclave closed system was used to simulate the hydrocarbon generation processes and establish the hydrocarbon generation mode of different types of ***,constrained by the thermal history and hydrocarbon generation kinetics,hydrocarbon generation histories were *** results show that hydrocarbon generation evolution can be divided into five stages,and the maturity of each stage is *** hydrocarbon generation history of the source rocks of the Shahejie 3 Formation mainly dates from the early depositional period of the Shahejie 1 Formation to the middle depositional period of the Dongying *** generation history constrained by thermal history and hydrocarbon generation kinetics is more in line with actual geological ***,this research can provide important hydrocarbon generation parameters for deep oil and gas exploration and exploitation of the Shahejie 3 Formation in the Dongpu Depression.

关键词： Dongpu depression Thermal history Hydrocarbon generation kinetics Hydrocarbon generation mode Hydrocarbon generation history

Asymmetric Trimethylsilylcyanation of Benzaldebyde Catalyzed by Novel Ti(Ⅳ)-Chiral Schiff Base Complexes

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Chinese Chemical Letters 1997年第12期8卷 0-0页

作者： Guo fu ZI cheng lie yin(Department of Chemistry, Beijing Normal University, Beijing, 100875)

Benzaldehyde has been trimethylsilylcyanated with a catalyst prepared in situ from titanium tetraisopropoxide and chiral Schiff bases. Cyanohydrin is obtalned in moderate ***

关键词： Asymmetric Trimethylsilylcyanation of Benzaldebyde Catalyzed by Novel Ti Chiral Schiff Base Complexes Base

Searching for^(76)Ge neutrinoless double beta decay with the CDEX-1B experiment

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Chinese Physics C 2024年第10期48卷 11-22页

作者： Bing-Tao Zhang Jun-Zheng Wang Li-Tao Yang Qian Yue Ke-Jun kang Yuan-Jing Li Hai-Peng An C.Greeshma Jian-Ping Chang Yun-Huan Chen Jian-Ping cheng Wen-Han Dai Zhi Deng Chang-Hao Fang Xin-Ping Geng Hui Gong Qiu-Ju Guo Xu-Yuan Guo Li He Sheng-Ming He Jin-Wei Hu Han-Xiong Huang Tu-Chen Huang Hai-Tao Jia Xi Jiang S.Karmakar Hao-Bin Li Jian-Min Li Jin Li Qian-Yun Li Ren-Ming-Jie Li Xue-Qian Li Yu-Lan Li Yi-Fan Liang Bin Liao Fong-Kay Lin Shin-Ted Lin Jia-Xuan Liu Shu-Kui Liu Yan-Dong Liu Yu Liu Yuan-Yuan Liu Zhong-Zhi Liu Hao Ma Yu-Cai Mao Qi-Yuan Nie Jin-Hua Ning Hui Pan Ning-Chun Qi Jie Ren Xi-Chao Ruan Ze She Manoj Kumar Singh Tian-Xi Sun Chang-Jian Tang Wei-You Tang Yang Tian Guang-fu Wang Li Wang Qing Wang Yu-Feng Wang Yun-Xiang Wang Henry-Tsz-King Wong Shi-Yong Wu Yu-cheng Wu Hao-Yang Xing Rui Xu yin Xu Tao Xue Yu-Lu Yan Nan Yi Chun-Xu Yu Hai-Jun Yu Jian-Feng Yue Ming Zeng Zhi Zeng Feng-Shou Zhang Lei Zhang Zhen-Hua Zhang Zhen-Yu Zhang kang-kang Zhao Ming-Gang Zhao Ji-Fang Zhou Zu-ying Zhou Jing-Jun Zhou Key Laboratory of Particle and Radiation Imaging(Ministry of Education)and Department of Engineering Physics Tsinghua UniversityBeijing 100084 Department of Physics Tsinghua UniversityBeijing 100084 Institute of Physics Academia SinicaTaipei 11529 NUCTECH Company Beijing 100084 YaLong River Hydropower Development Company Chengdu 610051 College of Nuclear Science and Technology Beijing Normal UniversityBeijing 100875 College of Physics Sichuan UniversityChengdu 610065 School of Physics Peking UniversityBeijing 100871 Department of Nuclear Physics China Institute of Atomic EnergyBeijing 102413 Sino-French Institute of Nuclear and Technology Sun Yat-sen UniversityZhuhai 519082 School of Physics Nankai UniversityTianjin 300071 Department of Physics Banaras Hindu UniversityVaranasi 221005 Department of Physics Beijing Normal UniversityBeijing 100875

We operated a p-type point contact high purity germanium(PPCGe)detector(CDEX-1B,1.008 kg)in the China Jinping Underground Laboratory(CJPL)for 500.3 days to search for neutrinoless double beta(0νββ)decay of^(76)Ge.A total of 504.3 kg⋅day effective exposure data was *** anti-coincidence and the multi/single-site event(MSE/SSE)discrimination methods were used to suppress the background in the energy region of interest(ROI,1989–2089 keV for this work)with a factor of 23.A background level of 0.33 counts/(keV⋅kg⋅yr)was *** lower limit on the half life of^(76)Ge 0νββdecay was constrained as T_(1/2)^(0ν)>1.0×10^(23)yr(90%C.L.),corresponding to the upper limits on the effective Majorana neutrino mass:<3.2–7.5 eV.

关键词： neutrinoless double beta decay CDEX point-contact germanium detector ^(76)Ge

铱(Ⅰ)联萘胺Schiff碱(BPMBNDI)配合物催化苯乙酮的不对称氢转移反应

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化学学报 1998年第5期56卷 484-488页

作者：自国甫尹承烈北京师范大学化学系北京100875

用旋光活性2,2′-(1,1′-联萘)二胺和2-吡啶基甲醛缩合得到的Schiff碱BPMBNDI[N,N′-二(2-吡啶基亚甲基)-(1,1′-联萘)-2,2′-二亚胺]为配体与[Ir(COD)Cl]_2(COD=1,5-环辛二烯)反应,生成了10个光学活性铱配合物.研究它们在异丙醇对苯乙... 详细信息

用旋光活性2,2′-(1,1′-联萘)二胺和2-吡啶基甲醛缩合得到的Schiff碱BPMBNDI[N,N′-二(2-吡啶基亚甲基)-(1,1′-联萘)-2,2′-二亚胺]为配体与[Ir(COD)Cl]_2(COD=1,5-环辛二烯)反应,生成了10个光学活性铱配合物.研究它们在异丙醇对苯乙酮不对称氢转移反应中的光学诱导活性时,发现10个催化剂均具有较高的立体选择性,其中[Ir(COD)(BPMBNDI)I]催化的光学产率高达84%.

关键词：铱配合物席夫碱不对称氢转移苯乙酮催化剂

In situ scattering study of multiscale structural evolution during liquid–liquid phase transition in Mg-based metallic glasses

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Rare Metals 2021年第11期40卷 3107-3116页

作者： kang-Hua Li Jia-cheng Ge Si-Nan Liu Shu fu Zi-Xuan yin Wen-Tao Zhang Guo-Xing Chen Shao-Chong Wei Hua Ji Tao Feng Qi Liu Xun-Li Wang Xiao-Bing Zuo Yang Ren Horst Hahn Si Lan Herbert Gleiter Institute of Nanoscience School of Materials Science and EngineeringNanjing University of Science and TechnologyNanjing 210094China Suzhou Nuclear Power Research Institute Co. LtdSuzhou 215004China Key Laboratory of Advanced Materials(MOE) School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China Department of Physics City University of Hong KongHong Kong 999077China Center for Neutron Scattering City University of Hong Kong Shenzhen Research InstituteShenzhen 518057China X-Ray Sciences Division Argonne National LaboratoryLemontIL 60439USA Institute of Nanotechnology Karlsruhe Institute of Technology(KIT)Eggenstein-Leopoldshafen 76344Germany

The glass-forming ability of Mg-Cu-Gd alloys could be significantly promoted with the addition of Ag.A calorimetric anomaly could be observed in the supercooled liquid region of the Mg-Cu-Ag-Gd metallic glass,indicating the occurrence of a liquid-state phase transition driven by ***,the underlying mechanism of the polyamorphous phase transition remains *** the paper,in situ scattering techniques were employed to reveal multiscale structure evidence in a Mg65Cu15Ag10Gd10metallic glass with an anomalous exothermic peak upon *** measurements indicate a reentrant behavior for the Mg-Cu-Ag-Gd metallic glass in the anomalous exothermic peak temperature region during *** situ synchrotron diffraction results revealed that the local atomic structure tends to be ordered and loosely packed first,followed by reentering into the initial state upon ***,time-resolved small-angle synchrotron X-ray scattering(SAXS) results show an increase in nanoscale heterogeneity first followed by a reentrant supercooled liquid behavior.A core-shell structure model has been used to fit the SAXS profiles when polyamorphous phase transition *** contrast,there is no structure anomaly for the reference Mg-Cu-Gd alloy *** detailed multiscale structural evidence suggests the occurrence of a liquid-liquid phase transition followed by a reentrant behavior in the MgCu-Ag-Gd metallic *** results deepen the understanding of the structural origin of the glass-forming ability and shed light on the possibility of tuning the physical and mechanical properties by heat-treatment in the supercooled liquid region of Mg-based metallic glasses.

关键词： Metallic glasses Anomalous exothermal peak Polyamorphous transition Synchrotron scattering