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Chinese Science Bulletin 1999年第23期44卷 2130-2136页

作者： renwei li Jinshi Chen Shukun Zhang Chinese Acad Sci Inst Geol Beijing 100029 Peoples R China Chinese Acad Geol Sci Inst Geomech Beijing 100083 Peoples R China

δ13C of dolostones from the Wumishan Formation (1 310-1 207 Ma) in the Ming Tombs area near Beijing ranges from - 1.5 to 1.5‰ (PDB), and generally, the δ18O ranges from - 4 to - 5‰ (PDB). The secular variation of stable carbon isotopic compositions is cyclic. δ13C displays positive shifts from a sequence boundary to 1.5 per mil (PDB), then

关键词： carbon and oxygen isotopes Mesoproterozoic. sea-level change.

Rb-Sr chronological characteristics of Jurassic granitoid gravels in north margin of Dabie block,Central China

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Chinese Science Bulletin 2001年第13期46卷 1126-1129页

作者： li Zhong li renwei Sun Shu Zhang Wenhua Chinese Acad Sci Inst Geol & Geophys Beijing 100029 Peoples R China

Granitoid gravels are discovered from alluvial fan conglomerates, the base of Jurassic Fenghuangtai Formation (J22), in the north margin of Dabie block and the south part of the Hefei Basin. These granitoid gravels make up 5%-10% of all gravels by volume percent. For the four components, K-feldspar, biotite, amphibole and whole rock divided from two selected granitoid gravel samples, their Rb-Sr isotopes are measured, which gives two formation ages of granitoids: (428±20) Ma and (430±54) Ma, and means that the Early Paleozoic granitoid intrusive rocks once existed in the Dabie Mountain provenances of Jurassic. The granitoids occur in the tectonic setting of post-collision upliftaccording to lithogeochemical discriminant analysis.

关键词： Dabie block Hefei Basin granitoid gravels Rb-Sr isotope chronology depositional provenance.

Sedimentary environment indicators: Benzothiazole and its derivatives

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Chinese Science Bulletin 2001年第5期46卷 412-416页

作者： li Yuan li renwei ZHOU Shixin LUO Binjie Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100029China Lanzhou Institute of Geology Chinese Academy of SciencesLanzhou 730000China

Benzothiazoles distributional characteristics of crude oils and non-hydrocarbon fractions of source rocks in Mangya depression of the Qaidam Basin, Lunnan oil field in the Tarim Basin, Kelamayi oil field in the Junggar Basin and the Tulufan Basin oil field were analyzed. It was found that the distributions of benzothiazole are remarkable diversity in different sedimentary environmental oils. The swamp crude oils contain high quantity of benzothiazole and relatively high quantity of alkylthio-benzothiazole and 2(3H)-benzothiazolone. But the quantity of the 2,2’-dithiobis-benzothiazole is relatively low. The abundance of benzothiazole and 2,2’-dithiobis-benzothiazole are relatively high insemi-brackish water lacustrine crude oils, but the quantity of alkylthio-benzothiazole and 2(3H)-benzothiazolone are relatively low. The benzothiazoles belong to weak acid and mild base compound, and their stabilization conditions relate to their environmental medium. The nitrogenous bases are in favor of alkalescence

关键词： crude oils source rock non-hydrocarbon fraction benzothiazoles sedimentary environment.

A Natural Deduction System of Temporal Logic

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Journal of Computer Science and Technology 1988年第3期3卷 173-185页

作者：黎仁蔚 Institute of Software Academia Sinica Beijing

This paper will present a natural deduction system of temporal logic,which includes two collections ofinference rules called “horizontal inference rules” and “vertical inference rules” *** is alsoproved that the system is both sound and complete under an appropriate *** natural andgenerally short,each proof in the system can be represented by a matrix whose entries serve to record theinference process.

关键词： Si A Natural Deduction System of Temporal Logic OA Pro oral

Facile synthesis of hierarchical NaX zeolite from natural kaolinite for efficient Knoevenagel condensation

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Chinese Journal of Chemical Engineering 2024年第1期65卷 75-84页

作者： Wen Xiao Peng Dong Chan Wang Jingdong Xu Tiesen li Haibo Zhu Tinghai Wang renwei Xu Yuanyuan Yue National Engineering Research Center of Chemical Fertilizer Catalyst College of Chemical EngineeringFuzhou UniversityFuzhou 350108China Qingyuan Innovation Laboratory Quanzhou 362801China Sinochem Quanzhou Energy Technology Co. Ltd.Quanzhou 362000China

Zeolite catalysts have found extensive applications in the synthesis of various fine ***,the micropores of zeolites impose diffusion limitations on bulky molecules,greatly reducing the catalytic ***,we explore an economic and environmentally friendly method for synthesizing hierarchical NaX zeolite that exhibits improved catalytic performance in the Knoevenagel condensation reaction for producing the useful fine chemical *** synthesis was achieved via a low-temperature activation of kaolinite and subsequent in-situ transformation strategy without any template or *** characterizations reveal that the synthesized NaX zeolite has both intercrystalline and intra-crystalline mesopores,smaller crystal size,and larger external specific surface area compared to commercial NaX *** mechanism investigations show that the inter-crystalline mesopores are generated by stacking smaller crystals formed from in-situ crystallization of the depolymerized kaolinite,and the intra-crystalline mesopores are inherited from the pores in the depolymerized *** synthesis strategy provides an energy-saving and effective way to construct hierarchical zeolites,which may gain wide applications in fine chemical manufacturing.

关键词： Hierarchical NaX zeolite Template-free synthesis Natural kaolinite Knoevenagel condensation

Preliminary report of coseismic surface rupture(part)of Türkiye's M_(W)7.8 earthquake by remote sensing interpretation

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Earthquake Research Advances 2024年第1期4卷 4-13页

作者： Yali Guo Haofeng li Peng liang renwei Xiong Chaozhong Hu Yueren Xu Key Laboratory of Earthquake Prediction Institute of Earthquake ForecastingChina Earthquake AdministrationBeijing100036China

Both M_(W) 7.8 and M_(W) 7.5 earthquakes occurred in southeastern Türkiye on February 6,2023,resulting in numerous buildings collapsing and serious *** the distribution of coseismic surface ruptures and secondary disasters surrounding the epicentral area is important for post-earthquake emergency and disaster ***-resolution Maxar and GF-2 satellite data were used after the events to extract the location of the rupture surrounding the first epicentral *** results show that the length of the interpreted surface rupture zone(part of)is approximately 75 km,with a coseismic sinistral dislocation of 2-3 m near the epicenter;however,this reduced to zero at the tip of the southwest section of the East Anatolia Fault ***,dense soil liquefaction pits were triggered along the rupture *** events are in the western region of the Eurasian Seismic Belt and result from the subduction and collision of the Arabian and African Plates toward the Eurasian *** western region of the Chinese mainland and its adjacent areas are in the eastern section of the Eurasian Seismic Belt,where seismic activity is controlled by the collision of the Indian and Eurasian *** China and Türkiye have independent tectonic histories.

关键词： 2023 Türkiye M_(w)7.8 earthquake Coseismic surface rupture East anatolian fault zone Eurasian seismic zone Remote sensing interpretation

Rhodium-Catalyzed Asymmetric Transfer Hydrogenation of Heterocyclic Diaryl Ketones:Facile Access to Key Intermediate of Baloxavir

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Chinese Journal of Chemistry 2024年第1期42卷 43-47页

作者： li Wang renwei Xiao Jingyuan Song Long-Sheng Zheng Qiwei Lang Gen-Qiang Chen Xumu Zhang Shenzhen Key Laboratory of Small Molecule Drug Discovery and Synthesis Department of Chemistryand Medi-PingshanSouthern University of Science and TechnologyShenzhenGuangdong 518000China Academy for Advanced Interdisciplinary Studies Southern Universityof Science and TechnologyShenzhenGuangdong 518000China Chemistry and Chemical Engineering Guangdong Laboratory ShantouGuangdong 515031China

Transition metal-catalyzed asymmetric transfer hydrogenation has been proven to be a powerful approach for the synthesis of chiral ***,a highly efficient and enantioselective transfer hydrogenation of dibenzoheptaheterocyclic ketones catalyzed by an arene-tethered TsDPEN-based Rh(ll)catalyst has been successfully developed,and a variety of dibenzoheptaheterocyclic ketones were reduced by a 1/1 mixture of formic acid and DBU(1,8-diazabicyclo[5.4.0]undec-7-ene)with high yields and *** this method,the asymmetric reduction of 7,8-difluorodibenzo[b,e]thiepin-11(6H)-one has been realized,providing the key intermediate of baloxavir marboxil with>99% yield and>99% ee at a substrate/catalyst molar ratio of 1000.

关键词： Asymmetric transfer hydrogenation Baloxavir Chiral alcohol Enantioselectivity Heterocyclic diaryl ketone Rhodium(Ⅱ)

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大别山周缘盆地物源研究:新结果及运用

沉积学报 2010年第1期28卷 102-117页

作者：李任伟中国科学院地质与地球物理研究所北京100029

叙述单颗粒碎屑矿物在大别山周缘盆地物源分析中的运用。现代河流沉积与大别山源区的对比研究表明碎屑石榴石、K-白云母和电气石的化学组成可以有效地被用于物源分析。它们在侏罗纪—白垩纪—古近纪沉积中的特征揭示了大别山源区岩石组... 详细信息

叙述单颗粒碎屑矿物在大别山周缘盆地物源分析中的运用。现代河流沉积与大别山源区的对比研究表明碎屑石榴石、K-白云母和电气石的化学组成可以有效地被用于物源分析。它们在侏罗纪—白垩纪—古近纪沉积中的特征揭示了大别山源区岩石组成的复杂性,由扬子大陆深俯冲折返所形成的高压—超高压变质岩在白垩纪—古近纪逐渐向东南缘盆地提供了重要的物源,在侏罗纪时期主要分布在大别山北缘盆地的源区。石炭纪时期大别山北缘盆地中碎屑Cr-尖晶石的化学组成和碎屑锆石U-Pb年龄结构指示源区岩石组成主要为早古生代华北大陆南缘活动大陆边缘的特征;此外,锆石U-Pb年龄指示源区岩石也具有扬子大陆的特征。

关键词：物源分析单颗粒碎屑矿物大别山侏罗纪石炭纪

大别山及邻区侏罗和石炭纪时期盆-山耦合:来自沉积记录的认识

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岩石学报 2005年第4期21卷 1133-1143页

作者：李任伟孟庆任李双应中国科学院地质与地球物理研究所北京100029 合肥工业大学资源与环境科学系合肥230009

侏罗纪时期大别造山带是合肥盆地的物源区。因此通过盆地中的沉积记录可以了解该造山带的地质演化,并重建造山带的古地理面貌。在合肥盆地最古老的中生代地层中(防虎山组,J_1),底部的沉积物源区主要为华北陆块早古生代和吕梁期(1700～19... 详细信息

侏罗纪时期大别造山带是合肥盆地的物源区。因此通过盆地中的沉积记录可以了解该造山带的地质演化,并重建造山带的古地理面貌。在合肥盆地最古老的中生代地层中(防虎山组,J_1),底部的沉积物源区主要为华北陆块早古生代和吕梁期(1700～1900Ma)的岩石。但是,从防虎山组沉积早-中期开始直至晚侏罗世,来自俯冲的扬子陆块折返的物质则构成为大别山的主体。防虎山组地层含高 Si 含量的碎屑多硅白云母和三叠纪年龄的锆石,三叠纪年龄的锆石含超高压(UHP)矿物包裹体,证明扬子大陆深俯冲(至地幔)的物质在早侏罗世时期已出露至大别山地表。高压-超高压的变质岩广泛分布於中-晚侏罗世时期东-中部的大别山,但向西逐渐消失。大别山北缘石炭系沉积岩的微量元素组成特征强烈指示它们应来源於一个被剥蚀的大陆岛弧。其碎屑锆石年龄结构主要由具有秦岭和二郎坪群特征(400～480Ma)的岩石组成、因此,大别山北缘石炭纪沉积主要来源于华北大陆南缘相当於秦岭和二郎坪群的岩石,物源区在早古生代时期曾经历过与秦岭造山带相似的岛弧构造环境的演化。大别山北缘晚石炭世沉积物中高 Si 含量碎屑多硅白云母的发现指示其沉积物源区可能出露有高压-超高压的变质岩。

关键词：合肥盆地侏罗纪石炭纪物源区超高压变质岩大别山

TSCompiler: efficient compilation framework for dynamic-shape models

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Science China(Information Sciences) 2024年第10期67卷 67-84页

作者： Xiang LUO Chen ZHANG Chenbo GENG Yanzhi YI Jiahui HU renwei ZHANG Zhen ZHANG Gianpietro CONSOLARO Fan YANG Tun LU Ning GU li SHANG School of Computer Science Fudan University School of Electronic Information and Electrical Engineering Shanghai Jiao Tong University School of Computer Science and Technology Harbin Institute of Technology Huawei Technologies Co. Ltd. Huawei Paris Research Center School of Microelectronics Fudan University

Today's deep learning models face an increasing demand to handle dynamic shape tensors and computation whose shape information remains unknown at compile time and varies in a nearly infinite range at runtime. This shape dynamism brings tremendous challenges for existing compilation pipelines designed for static models which optimize tensor programs relying on exact shape values. This paper presents TSCompiler, an end-to-end compilation framework for dynamic shape models. TSCompiler first proposes a symbolic shape propagation algorithm to recover symbolic shape information at compile time to enable subsequent optimizations. TSCompiler then partitions the shape-annotated computation graph into multiple subgraphs and fine-tunes the backbone operators from the subgraph within a hardware-aligned search space to find a collection of high-performance schedules. TSCompiler can propagate the explored backbone schedule to other fusion groups within the same subgraph to generate a set of parameterized tensor programs for fused cases based on dependence analysis. At runtime, TSCompiler utilizes an occupancy-targeted cost model to select from pre-compiled tensor programs for varied tensor shapes. Extensive evaluations show that TSCompiler can achieve state-of-the-art speedups for dynamic shape models. For example, we can improve kernel efficiency by up to 3.97× on NVIDIA RTX3090, and 10.30× on NVIDIA A100 and achieve up to five orders of magnitude speedups on end-to-end latency.

关键词： machine learning tensor compilers dynamic shape operator fusion code generation auto-tuning