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Automatic Extraction Method of 3D Feature Guidelines for Complex Cultural Relic Surfaces Based on Point Cloud

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Journal of Geodesy and Geoinformation Science 2024年第1期7卷 16-41页

作者： geng Yuxin ZHONG Ruofei HUANG Yuqin SUN Haili College of Resources Environment and Tourism Capital Normal UniversityBeijing 100048China Key Laboratory of 3-Dimensional Information Acquisition and Application Ministry of EducationBeijing 100048China Chinese Academy of Cultural Heritage Beijing 100029China

Cultural relics line graphic serves as a crucial form of traditional artifact information documentation,which is a simple and intuitive product with low cost of displaying compared with 3D *** reduction is undoubtedly necessary for line ***,most existing methods for artifact drawing rely on the principles of orthographic projection that always cannot avoid angle occlusion and data overlapping while the surface of cultural relics is ***,conformal mapping was introduced as a dimensionality reduction way to compensate for the limitation of orthographic *** on the given criteria for assessing surface complexity,this paper proposed a three-dimensional feature guideline extraction method for complex cultural relic surfaces.A 2D and 3D combined factor that measured the importance of points on describing surface features,vertex weight,was *** the selection threshold for feature guideline extraction was determined based on the differences between vertex weight and shape index *** feasibility and stability were verified through experiments conducted on real cultural relic surface *** demonstrated the ability of the method to address the challenges associated with the automatic generation of line drawings for complex *** extraction method and the obtained results will be useful for line graphic drawing,displaying and propaganda of cultural relics.

关键词： point cloud conformal parameterization vertex weight surface mesh cultural relics feature extraction

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Artemsieverolactones A—H,Eight Guaiane-Type Sesquiterpenoid Trimers from Artemisia sieversiana

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Chinese Journal of Chemistry 2024年第10期42卷 1084-1092页

作者： Wei Dong Xiao-Yan Huang Tian-Ze Li Yan-Mei Weng Chang-An geng Ji-Jun Chen State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China University of Chinese Academyof Sciences Beijing 100049China

Eight new guaiane-type sesquiterpenoid trimers,artemsieverolactones A—H,possessing unprecedented scaffolds via biocatalyzed[4+2]Diels−Alder cycloaddition reactions were identified from Artemisia *** structures were determined by comprehensive spectroscopic data,single-crystal X-ray diffraction analyses,and ECD *** terms of structure,artemsieverolactones A—H are first examples of sesquiterpenoid trimers from guaiane-type sesquiterpenoid through four different[4+2]Diels−Alder cycloaddition *** fibrosis assay suggested that five compounds exhibited activity against HSC-LX2 with IC_(50)values ranging from 37.8 to 117.1μmol/*** most active artemsieverolactone B(2)displayed significant inhibitory activity against HSC-LX2 with IC_(50)value of 37.8μmol/L,which was 3 times more active than the positive drug silybin(IC_(50),139.7μmol/L).Preliminary mechanism study revealed that artemsieverolactone B could inhibit the deposition of human collagen typeⅠ(ColⅠ),human hyaluronic acid(HA),and human laminin(HL)with IC_(50)values of 40.4μmol/L(Col I),55.1μmol/L(HL),47.3μmol/L(HA),which was 2 to 3-fold more potent than silybin.

关键词： Artemisia sieversiana Artemsieverolactones A-H Guaiane-type sesquiterpenoid trimers Antihepatic fibrosis Extracellular matrix Cancer NMR spectroscopy X-ray diffraction

The Influence of the Closure of the East Paleo-Tethys Ocean on Southern South China: Evidences from Kinematics and 40Ar/39Ar Geochronology of the Rongxian Ductile Shear Zone in Southeastern Guangxi

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ACTA GEOLOGICA SINICA-ENGLISH EDITION 2024年第5期98卷 1125-1140页

作者： Huang, Wenqiang Li, Saisai Xin, Liangwei Feng, Zuohai Zhang, Hongrui geng, Jieli Liu, Kun Shi, Chunyan Guilin Univ Technol Collaborat Innovat Ctr Explorat Nonferrous Met Dep Guilin 541004 Guangxi Peoples R China Guilin Univ Technol Coll Earth Sci Guilin 541004 Guangxi Peoples R China Chinese Acad Geol Sci Inst Geol Beijing 100037 Peoples R China Guilin Univ Technol Coll Tourism & Landscape Architecture Guilin 541004 Guangxi Peoples R China

The Triassic was a crucial period in the tectonic evolution of the South China Block. Research on tectonic deformation during this period provides information on intracontinental orogenic mechanisms in South China. In this study, alongside thermochronological analyses, we examine the macroscopic and microscopic structural features of the Rongxian ductile shear zone, located south of the Darongshan granite in the southeastern part of Guangxi Province, on the southern margin of South China. Sinistral shear is indicated by the characteristics of rotated sigma-type feldspar porphyroclasts, stretching lineations defined by elongated quartz grains and the orientations of quartz c-axes. LA-ICP-MS U-Pb dating of zircons from two samples of granitic mylonite and one of granite yielded ages of ca. 256 Ma. Furthermore, two samples of granitic mylonite yield muscovite Ar-40/Ar-39 plateau ages of 249-246 Ma. These results indicate that the Rongxian ductile shear zone resulted from Early Triassic deformation of the late Permian Darongshan granite. This deformation was likely related to the closure of the eastern Paleo-Tethys Ocean and the subsequent collision of the South China and Indochina blocks, during the early stage of the Indosinian orogeny.

关键词： ductile shear zone Ar-40/Ar-39 geochronology Triassic South China Block East Paleo-Tethys Ocean AILAOSHAN SUTURE ZONE ULTRAHIGH-TEMPERATURE METAMORPHISM ARC/BACK-ARC ASSEMBLAGES PLATE TECTONIC CYCLE TRUONG SON BELT VOLCANIC-ROCKS INDOSINIAN COLLISION PLASTIC-deFORMATION MESOZOIC GRANITOIDS GRANULITE ENCLAVES

A dual-band wireless communication of spoof plasmonic meta-waveguide

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Science China(Information Sciences) 2024年第7期67卷 337-338页

作者： Xinxin GAO geng-Bo WU Ze GU Qian MA Wenyi CUI Tiejun CUI Chihou CHAN State Key Laboratory of Terahertz and Millimeter Waves City University of Hong Kong State Key Laboratory of Millimeter Waves Southeast University department of Electrical Engineering City University of Hong Kong

The ever-growing demands in wireless communications,computational imaging, and light detection necessitate the capability to freely manipulate electromagnetic *** and highly integrated devices hold great promise for the future of communications. Spoof plasmonic metamaterials, in particular, have shown potential in creating functional devices and systems due to their ultracompact and low-profile advantages [1–3].

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Study on the catch,bycatch and discard of Chinese pelagic longline fisheries in the Atlantic Ocean

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Aquaculture and Fisheries 2024年第2期9卷 280-286页

作者： Boyi Pan Jiangfeng Zhu Qinqin Lin Zhe geng Feng Wu Yuying Zhang College of Marine Sciences Shanghai Ocean UniversityShanghai201306China Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources Ministry of EducationShanghai Ocean UniversityShanghai201306China department of Biological Sciences Florida International UniversityNorth MiamiFL33181USA

Catch,bycatch and discard information is important for the assessment and management of *** Chinese pelagic tuna longline observer data from 2010 to 2018,we studied the catch composition in the Chinese pelagic tuna longline fisheries in Atlantic targeting bigeye tuna(Thunnus obesus)and bluefin tuna(Thunnus thynnus),and analyzed the survival status and discard rates of common bycatch species.A total of 55 species,including tunas,billfishes,sharks,sea turtles,cetaceans,seabirds,and other pelagic species,were *** results indicated that the catch composition of the Chinese pelagic tuna longline fishery targeting bigeye tuna was significantly different from that targeting bluefin *** annual discard rates of common species decreased over this *** rate by length and discard mortality for common species were varied among *** is the first study to estimate catch,bycatch,and discard using Chinese pelagic tuna longline observer data in the Atlantic Ocean,which is important for the management of Chinese tuna longline fisheries in Atlantic Ocean.

关键词： Longline fishery Catch composition Discard Size distribution Atlantic

Evaluation of suitability of university ladder classroom environment on humans

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Energy and Built Environment 2024年第4期5卷 615-627页

作者： Xin Liu Xiu geng Kailiang Huang Guohui Feng He Zhao Xiaotong Wang Jianing He School of Municipal and Environment Engineering Shenyang Jianzhu UniversityShenyang 100168China Jianke EET Co. Ltd.Beijing 100013China

Evaluation of the suitability of university ladder classroom environment on humans is an effective approach to improve the quality of the indoor environment and protect human ***,there are unresolved issues regarding the suitability of university ladder classroom environment for *** example,the design of en-closure structure and heating ventilation and air conditioning(HVAC)system is unreasonable,and the indoor air quality does not meet the required *** this study,the suitability of university ladder classroom environ-ment on humans was considered the research *** evaluation indices of indoor environment were selected from indoor air quality,indoor thermal and humid environments,light environment,and sound *** the health and comfort of users were taken as the evaluation indices of *** to the results of expert investigations and case measurements,the index weight was determined by the expert-entropy weight method,and a complete evaluation system of indices was *** were two first-level,six second-level,and fourteen third-level indices in the evaluation *** evaluation indices of each level with the largest weight were indoor environment(0.5940),user health(0.2530),and indoor temperature(0.1175)*** comparing the actual learning effect to the evaluation results,the applicability of the evaluation system was *** evaluation system of the suitability of university ladder classroom environment on humans is convenient for operators to identify the weak points between humans and the *** evaluation system is endowed with important theoretical and practical significance to realize the green development of colleges and universities and build an environment-friendly campus.

关键词： Severe cold region Suitability of environment on humans Natural ventilation Expert-entropy weight method Evaluation system

The effects of in ovo feeding of selenized glucose on liver selenium concentration and antioxidant capacity in neonatal broilers

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Chinese Chemical Letters 2024年第6期35卷 312-315页

作者： Jiahui Li Qiao Shi ying Xue Mingde Zheng Long Liu Tuoyu geng Daoqing Gong Minmeng Zhao Jiangsu Key Laboratory of Animal genetic Breeding and Molecular design College of Animal Science and TechnologyYangzhou UniversityYangzhou 225009China Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry of Education of China Yangzhou UniversityYangzhou 225009China

Selenium is an essential trace element for humans and *** the active center of selenoproteins,the addition of selenium is beneficial to enhance the antioxidant ***,the high cost limits the application of organic Se in agriculture animal *** glucose(SeGlu)is a newly invented organoselenium material with good stability,low toxicity and low *** assay found that SeGlu was able to increase selenium deposition in liver of newborn broilers,and enhance the antioxidant capacity of liver by elevating the activities of antioxidant enzymes such as total superoxide dismutase and glutathione *** paper as the first example clarifying the mechanism of SeGlu to enhance the antioxidant ability of chicks,shows that SeGlu can be used as an organic selenium enrichment additive for early nutrition of *** a cross-discipline study involving chemistry,biology and agriculture animal science,the work may be beneficial for studies in related fields and prompt the development of the selenium science.

关键词： Selenized glucose In ovo feeding Antioxidant capacity Selenium Broiler

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High-efficiency PdNi single-atom alloy catalyst toward cross-coupling reaction

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Chinese Chemical Letters 2024年第7期35卷 480-483页

作者： Baokang geng Xiang Chu Li Liu Lingling Zhang Shuaishuai Zhang Xiao Wang Shuyan Song Hongjie Zhang State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China department of Chemistry Tsinghua UniversityBeijing 100084China

The preparation of Pd-based catalysts with rich electrons and a high atom dispersion rate is of great significance for improving the reactivity of cross-coupling reactions,which is a powerful tool for pharmaceutical and fine chemical ***,we report a PdNi single-atom alloy(SAA)catalyst in which isolated Pd single atoms are anchored onto the surface of Ni nanoparticles(NPs)applied for Suzuki coupling reactions and Heck coupling *** 0.1%PdNi SAA exhibits extraordinary catalytic activity(reaction rate:17,032.25 mmol h^(-1)gPd^(-1))toward the Suzuki cross-coupling reaction between 4-bromoanisole and phenylboronic acid at 80℃for 1 *** excellent activity is supposed to attribute to the 100 percent utilization rate of Pd atoms and the highly stable surface zero-valance Pd atoms,which provides abundant sites and electrons for the adsorption and fracture of the C-X(X=Cl,Br,I)***,our work demonstrates the excellent application prospect of SAAs for cross-coupling reactions.

关键词： Single-atom alloy Cross-coupling reaction Palladium catalysis Heterogeneous catalysis High-efficiency

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A Transient-Pressure-Based Numerical Approach for Interlayer Identification in Sand Reservoirs

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Fluid Dynamics & Materials Processing 2024年第3期20卷 641-659页

作者： Hao Luo Haibo deng Honglin Xiao Shaoyang geng Fu Hou Gang Luo Yaqi Li Tight Oil and Gas Exploration and development Project department PetroChina Southwest Oil and Gas Field CompanyChengdu610051China Energy College Chengdu University of TechnologyChengdu610059China

Almost all sandstone reservoirs contain interlayers. The identification and characterization of these interlayers iscritical for minimizing the uncertainty associated with oilfield development and improving oil and gas *** interlayers outside wells using identification methods based on logging data and machine learning isdifficult and seismic-based identification techniques are expensive. Herein, a numerical model based on seepageand well-testing theories is introduced to identify interlayers using transient pressure data. The proposed modelrelies on the open-source MATLAB Reservoir Simulation Toolbox. The effects of the interlayer thickness, position,and width on the pressure response are thoroughly investigated. A procedure for inverting interlayer parametersin the reservoir using the bottom-hole pressure is also proposed. This method uses only transient pressuredata during well testing and can effectively identify the interlayer distribution near the wellbore at an extremelylow cost. The reliability of the model is verified using effective oilfield examples.

关键词： Sand reservoir interlayer identification transient pressure analysis numerical well test