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Stereoselective Synthesis of 2-Chloro-4-Substituted-phenyl-5,5-Dimethyl-1,3,2-Dioxaphosphorinan-2-(Thi)ones

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Chinese Chemical Letters 1997年第10期8卷 855-858页

作者： rui lian shao Guang Fu YANG Wei Shi MIAO Min Hua YANG(National Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin, 300071) NANKAI UNIV NATL KEY LAB ELEMENTOORGAN CHEMTIANJIN 300071PEOPLES R CHINA

The stereoselective synthesis of 2-chloro-4-substituted-phenyl-5,5-dimethyl-1,3,2-dioxaphosphorinan-2-(thi)ones is described. Only single trans-isomers were obtained when 1-substituted-phenyl-2,2-dimethyl-1,3-propanediols (1) reacted with POCl3. But the stereoselectivity of cyclization reaction between (1) and PSCl3 depended greatly upon the reaction condition. The configurational assignments and the ratio of cis-/trans- diastereoisomers of the products were performed on the basis of (HNMR)-H-1, (PNMR)-P-31 and IR spectra and confirmed by X-ray diffraction analyses.

关键词： HNMR Cl Stereoselective Synthesis of 2-Chloro-4-Substituted-phenyl-5,5-Dimethyl-1,3,2-Dioxaphosphorinan-2 Thi)ones

HIGHLY REGIOSELECTIVE O-AND N-ACYLATION OF 5-METHYL-3-HYDROXYISOXAZOLE

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Chinese Chemical Letters 1992年第3期3卷 175-176页

作者： rui lian shao Cheng Xin ZHI You Quan ZHU Jie You XUE National Laboratory of Elemento-Organic Chemistry Nankai UniversityTianjin 300071.

Acylation of 5-methyl-3-hydroxyisoxazole (1) with 3-substituted cyclopropanecarboxylic chlorides (3) in the presence of triethylamine (TEA) in acetonitrile yields predominantly O-acylated products (4).The N-acyl isome... 详细信息

关键词： HIGHLY REGIOSELECTIVE O-AND N-ACYLATION OF 5-METHYL-3-HYDROXYISOXAZOLE TEA

THE NEGATIVE-ION CHEMICAL-IONIZATION MASS SPECTRA OF SOME 2, 6, 7-TRIOXA-1-PHOSPHABICYCLO[2.2.2]OCTANE-1-OXIDE DERIVATIVES

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Chinese Chemical Letters 1991年第8期2卷 631-632页

作者： Jie You XUE Da Zhi TANG rui lian shao Shi Xiong TANG Elemento-Organic Chemistry Laboratory Nankai University Department of Chemistry Nankai UniversityTianjin 300071. Central Laboratory of Tianjin Tianjin 300074.

The metaphosphate anion, PO_3, was detected in the negative-ion chemicalionization mass spectra of 2,6,7-trioxa-1-phospbabicyclo[2.2. 2] octane-1-oxides.

关键词： ION THE NEGATIVE-ION CHEMICAL-IONIZATION MASS SPECTRA OF SOME 2 TRIOXA-1-PHOSPHABICYCLO[2.2.2]OCTANE-1-OXIDE DERIVATIVES OC

STEREOCHEMISTRY　OF　CYCLIC　ORGANOPHOSPHORUS　COMPOUNDS－ⅡMETHANOLYSIS　OF　2－CHLORO－4－PHENYL－5，5－DIMETHYL－1，3，2－DIOXAPHOSPHORINAN－2－THIONE：RETENTION　OF　CONFIGURATION　AS　WELL　AS　WELL　AS　RING　OPENING　ISOMERIZATION

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Chinese Chemical Letters 1994年第4期5卷 281-282页

作者： rui lian shao WEI sHI MIAO(Naticaal Laboratory of Elemento-Organic Chemistry, Nankai UniversityTianjin 300071)

The reaction of cis- 2- chloro- 4- phenyl- 5, 5- dimethyl- 1, 3. 2-dioxaghosghor inan-2- thione (Ⅰ) with methoxide or phenoxide at room temperatute takes place with retent ion of configuration. while refluxing cis- (1) and methoxide in methanol, gartial isomerization of cis-thioghosphate (2) to its trans isomer occursand an acyclic intermediate (3) is found to be involved in this grocess

关键词： AS WELL CONFIGURATION RETENTION RING CHLORO COMPOUNDS

Efficient Isomerization for Preparing thans-2,2-Dimethyl-3-(2,2-dichloroethenyl) cyclopropanecarbonyl Chloride

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Chinese Chemical Letters 1999年第2期10卷 101-102页

作者： Jun An MA Run Qiu HUANG Jun Ran CHENG rui lian shao Zai Guo LI(Institute and State Key Laboratory of Elemento-organic Chemistry, Nankai University, Tianjin300071) Inst. State Key Lab. Elemento-O. Nankai University Tianjin 300071 China

Trans-2,2-dimethyl-3-(2,2-dichloroethenyl)cyclopropanecarbonyl chloride, which is animportant intermediate for insecticides, is obtained by isomerization of the cis/trans-mixture with4- (N,N-dimethylamino) pyridine (D... 详细信息

关键词： Permethric acid chloride dimethylaminopyridine conversion

Morphogenesis and Molecular Phylogeny of a Marine Urostylid Ciliate Apokeronopsis wrighti(Protista, Ciliophora, Hypotrichia)

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Journal of Ocean University of China 2024年第4期23卷 1067-1075页

作者： lian Chunyu LI Ping ZHANG Tengteng shao Chen Department of Zoology College of Life SciencesShaanxi Normal UniversityXi’an 710119China Powerchina Northwest Engineering Corporation Limited Xi’an 710065China

Hypotrichs are one of the highly differentiated ciliated lineages which play important roles in ecological, environmental,evolutionary and basic biological studies. In the present study, we investigated the living characteristics, infraciliature, nuclear apparatus, ontogenesis and phylogenetic position of a marine hypotrichous ciliate, Apokeronopsis wrighti Long et al., 2008, which was isolated from coastal waters in Shenzhen, China. The new isolate resembles the type population in terms of morphological characteristics, morphometrics, and SSU rRNA gene sequence that is with a 99.7% similarity. Ontogenesis of A. wrighti is characterized by oral primordium for the proter as well as marginal and dorsal kineties anlagen in both filial products formed de novo, and the cirral row arranged along the paroral and endoral arises from several anterior frontoventral-transverse cirral streaks. Phylogenetic analyses based on SSU and concatenated gene data suggest that five species of Apokeronopsis form a monophyletic clade, and the genus Apokeronopsis is closely related to Thigmokeronopsis and Metaurostylopsis.

关键词： 18S rRNA gene Apokeronopsis ciliated protists multi-gene ontogenesis systematics Urostylida

SYNTHESIS OF NEW CYCLIC PHOSPHATES OF 3-HYDROXYISOXAZOLE AND THEIR DIASTEREOMERS

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Chinese Chemical Letters 1993年第9期4卷 767-768页

作者： rui lian shao Min Hua YANG Cheng Xin ZHI The National Laboratory of Elemento-organic Chemistry NanKai University,Tianjin 300071

Keeping in view the biological activities of 3-hydroxyisoxa- zole and cyclic phosphate derivatives,some compounds possessing these two moieties have been synthesized,the structural elucidation of these diastereomers was made depending on spectral *** mechanism could be illustrated by the theories of trigonal bipyramide intermediate and pseudorotation.

关键词： SYNTHESIS OF NEW CYCLIC PHOSPHATES OF 3-HYDROXYISOXAZOLE AND THEIR DIASTEREOMERS THF

Identification of reservoir types in deep carbonates based on mixedkernel machine learning using geophysical logging data

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Petroleum Science 2024年第3期21卷 1632-1648页

作者： Jin-Xiong Shi Xiang-Yuan Zhao lian-Bo Zeng Yun-Zhao Zhang Zheng-Ping Zhu shao-Qun Dong Key Laboratory of Exploration Technologies for Oil and Gas Resources of the Ministry of Education Yangtze UniversityWuhan4310HubeiChina School of Geosciences Yangtze UniversityWuhan430100HubeiChina College of Geosciences China University of Petroleum(Beijing)Beijing102249China Petroleum Exploration and Production Research Institute of SINOPEC Beijing100083China School of Earth Sciences and Engineering Xi'an Shiyou UniversityXi'an 710065ShaanxiChina

Identification of reservoir types in deep carbonates has always been a great challenge due to complex logging responses caused by the heterogeneous scale and distribution of storage *** cross-plot analysis and empirical formula methods for identifying reservoir types using geophysical logging data have high uncertainty and low efficiency,which cannot accurately reflect the nonlinear relationship between reservoir types and logging ***,the kernel Fisher discriminant analysis(KFD),a kernel-based machine learning technique,attracts attention in many fields because of its strong nonlinear processing ***,the overall performance of KFD model may be limited as a single kernel function cannot simultaneously extrapolate and interpolate well,especially for highly complex data *** address this issue,in this study,a mixed kernel Fisher discriminant analysis(MKFD)model was established and applied to identify reservoir types of the deep Sinian carbonates in central Sichuan Basin,*** MKFD model was trained and tested with 453 datasets from 7 coring wells,utilizing GR,CAL,DEN,AC,CNL and RT logs as input *** particle swarm optimization(PSO)was adopted for hyper-parameter optimization of MKFD *** evaluate the model performance,prediction results of MKFD were compared with those of basic-kernel based KFD,RF and SVM ***,the built MKFD model was applied in a blind well test,and a variable importance analysis was *** comparison and blind test results demonstrated that MKFD outperformed traditional KFD,RF and SVM in the identification of reservoir types,which provided higher accuracy and stronger *** MKFD can therefore be a reliable method for identifying reservoir types of deep carbonates.

关键词： Reservoir type identification Geophysical logging data Kernel Fisher discriminantanalysis Mixedkernel function Deep carbonates

Epicardial adipose tissue in obesity with heart failure with preserved ejection fraction: Cardiovascular magnetic resonance biomarker study

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World Journal of Cardiology 2024年第3期16卷 149-160页

作者： Ju-Wei shao Bing-Hua Chen Kamil Abu-Shaban Ahmad Baiyasi lian-Ming Wu Jing Ma Department of Radiology The Affiliated Hospital of Yunnan UniversityKunming 650021Yunnan ProvinceChina Department of Radiology Ren Ji HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200127China Department of Radiology University of Toledo College of MedicineToledoOH 43623United States Department of Radiology Wayne State University School of MedicineDetroitMI 48201United States Department of Endocrinology Ren Ji HospitalShanghai Jiao Tong University School of MedicineShanghai 200127China

BACKGROUND Obesity has become a serious public health issue,significantly elevating the risk of various *** is a well-established contributor to Heart failure with preserved ejection fraction(HFpEF).Evaluating HFpEF in obesity is *** adipose tissue(EAT)has emerged as a valuable tool for validating prognostic biomarkers and guiding treatment ***,assessing EAT is of paramount *** magnetic resonance(CMR)imaging is acknowledged as the gold standard for analyzing cardiac function and *** hope to use CMR to assess EAT as a bioimaging marker to evaluate HFpEF in obese *** To assess the diagnostic utility of CMR for evaluating heart failure with preserved ejection fraction[HFpEF;left ventricular(LV)ejection fraction≥50%]by measuring the epicardial adipose tissue(EAT)volumes and EAT mass in obese *** Sixty-two obese patients were divided into two groups for a case-control study based on whether or not they had heart failure with *** two groups were defined as HFpEF+and HFpEF-.LV geometry,global systolic function,EAT volumes and EAT mass of all subjects were obtained using cine magnetic resonance *** Forty-five patients of HFpEF-group and seventeen patients of HFpEF+group were *** mass index(g/m2)of HFpEF+group was higher than HFpEF-group(P<0.05).In HFpEF+group,EAT volumes,EAT volume index,EAT mass,EAT mass index and the ratio of EAT/[left atrial(LA)left-right(LR)diameter]were higher compared to HFpEF-group(P<0.05).In multivariate analysis,Higher EAT/LA LR diameter ratio was associated with higher odds ratio of *** EAT/LA LR diameter ratio is highly associated with HFpEF in obese *** is plausible that there may be utility in CMR for assessing obese patients for HFpEF using EAT/LA LR diameter ratio as a diagnostic *** prospective studies,are needed to validate these proof-of-concept findings.

关键词： Heart failure with preserved ejection fraction Epicardial adipose tissue Obesity Cardiac magnetic resonance