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Rhodium-Catalyzed Regioselective C-O and C-C Bonds Formation of 3-Oxopent-4-enenitriles with Alkynes for the Synthesis of Polysubstituted 2H-Pyrans

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Chinese Journal of Chemistry 2024年第17期42卷 1986-1992页

作者： Kelu Yan Xiao liu Jiangwei wen Qiuyun li Junjie wang Yang Zheng Xiu wang Key Laboratory of life-Organic Analysis of Shandong Province School of Chemistry and Chemical EngineeringQufu Normal UniversityQufuShandong273165China Faculty of Chemistry and Chemical Engineering Yancheng Institute of TechnologyYanchengJiangsu 224051China

The rhodium-catalyzed C-H bond activation and cyclization of 3-oxopent-4-enenitriles with alkynes proceed *** 2H-pyrans with multiple substituents are achieved in good yields through regioselective formation of C-O and C-C *** involving hydroxy-alkynoates resulted in products with a furo[3,4-b]pyran skeleton via further intramolecular ester exchange *** from the traditional"1-oxatrienes pathway",this method for the synthesis of useful 2H-pyrans possesses certain highlights in terms of readily available substrates,stable and easily derivatized products,gentle and convenient operation process,and step and atomeconomy.

关键词： Rhodium/C-H activation 3-Oxopent-4-enenitriles Alkynes 2H-Pyrans Transition metals Regioselectivity Cyclization Comprehensive Summary

Two-Staged Method for Ice Channel Identification Based on Image Segmentation and Corner Point Regression

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China Ocean Engineering 2024年第2期38卷 313-325页

作者： DONG wen-bo ZHOU li DING Shi-feng wang Ai-ming CAI Jin-yan School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China

Identification of the ice channel is the basic technology for developing intelligent ships in ice-covered waters,which is important to ensure the safety and economy of *** the Arctic,merchant ships with low ice class often navigate in channels opened up by *** in the ice channel often depends on good maneuverability skills and abundant experience from the captain to a large *** ship may get stuck if steered into ice fields off the *** this circumstance,it is very important to study how to identify the boundary lines of ice channels with a reliable *** this paper,a two-staged ice channel identification method is developed based on image segmentation and corner point *** first stage employs the image segmentation method to extract channel *** the second stage,an intelligent corner regression network is proposed to extract the channel boundary lines from the channel region.A non-intelligent angle-based filtering and clustering method is proposed and compared with corner point regression *** training and evaluation of the segmentation method and corner regression network are carried out on the synthetic and real ice channel *** evaluation results show that the accuracy of the method using the corner point regression network in the second stage is achieved as high as 73.33%on the synthetic ice channel dataset and 70.66%on the real ice channel dataset,and the processing speed can reach up to 14.58frames per second.

关键词： ice channel ship navigation identification image segmentation corner point regression

Effects of Enclosure on Grassland Ecological and Economic Benefits in Northern China

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Chinese Geographical Science 2024年第1期34卷 67-78页

作者： HU Bo wen Qingke XI Fengjiang li Mengyao wang libing REN Yuejuan Aerospace Information Research Institute Chinese Academy of SciencesBeijing100094China University of Chinese Academy of Sciences Beijing100049China Inner Mongolia Remote Sensing Center Co. Ltd.Huhhot010000China Xilinhot the Maodeng pasture Xilinhot026000China China University of Mining and Technology Xuzhou221116China Shanxi Provincial Key Lab of Resources Environment and Disaster MonitoringCoal Geological Geophysical Exploration Surveying&Mapping Institute of Shanxi ProvinceJinzhong030600China

Grasslands in northern China serve the country as both an ecological barrier and a livestock production ***,installing enclosures has been becoming the major grassland restoration measure adopted by many local ***,the effects of restoration on both ecological and production benefits of grassland remain unclear for implemented grassland restoration ***,a representative rangeland in northern China,the Maodeng pasture in Inner Mongolia Autonomous Region was selected as the study area,and remote sensing monitoring analyses were carried out to quantify the ecological benefits and economic benefits from 2015 to *** results showed that:1) in terms of ecological benefits,the grassland area with a grassland coverage rate of more than 60% accounts for 32.3% of the regional area,and 86.4% of its grassland grew significantly better than the same period in2015,showing a significant improvement in grassland *** the average amount of carbon per unit area as the ecological benefit evaluation index,it increased by 27.1% to 32.48Tg C/yr from 2015 to 2021.2) In terms of economic benefits,both theoretical grass production and livestock carrying capacity increased from 2015 to *** to 2015,the theoretical grass production in 2021 increased by 24.8% to 71 900 *** livestock carrying capacity reached 52 100 sheep units in 2021,nearly 11 000 sheep units more than that in *** the study period,multiple economic indicators(on a per capita basis of permanent residents) for the pastoral area of Xilinhot City to which the Maodeng pasture belongs,have grown *** capita total income rose from 29 630 yuan(RMB) in2015 to 62 859 yuan(RMB) in *** on grassland resources to develop the pastoral ecology also broadens the potential economic development ***,the establishment of the reserve and the experiment of implanting an enclosure policy have had a significant and positive impact on Maodeng pasture’s develo

关键词： enclosure grassland ecological benefit economic benefit Maodeng pasture Inner Mongolia northern China

Hydrodechlorination of trifluoro-trichloroethane to chlorotrifluoroethylene:Revealing the deactivation mechanism and regeneration strategy of Pd-Cu/AC catalyst

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Chinese Journal of Chemical Engineering 2024年第6期70卷 261-268页

作者： Song Tian Yicheng Chen Xiaoyu wen Bingcheng li Jian Lu Zile li Feng Feng Qingtao wang Qunfeng Zhang Xiaonian li State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology Institute of Industrial Catalysis of Zhejiang University of TechnologyHangzhou 310014China State Key Laboratory of Fluorine&Nitrogen Chemicals Xi'an Modern Chemistry Research InstituteXi'an 710065China

Chlorotrifluoroethylene(CTFE)is a vital fluorinated olefinic monomer produced through the catalytic hydrodechlorination of trichlorotrifluoroethane(CFC-113),an eco-friendly ***,hydrodechlorination catalysts for olefin production often suffer from poor *** Pd/AC catalyst and Pd-Cu/AC catalyst prepared by co-impregnation method exhibited poor stability,Pd-Cu/AC catalyst with CFC-113 conversion dropping to around 37%after 50 h of hydrodechlorination ***-Emmett-Teller,transmission electron microscopy,X-ray photoelectron spectroscopy,and X-ray diffraction of fresh and deactivated Pd/AC catalysts indicate that the deactivation of Pd/AC catalysts is due to high-temperature agglomeration of *** analysis of fresh and deactivated Pd-Cu/AC catalysts using Brunauer-Emmett-Teller,transmission electron microscopy,and thermogravimetric analysis techniques revealed decreased dispersion of active sites,reduced surface area,catalyst aggregation deactivation,and a significant decrease in Cu ***,the results of NH3-TPD revealed that the acid sites of the catalyst increased significantly.X-ray diffraction spectra indicated the formation of new species,basic copper chloride(Cu_(2)(OH)_(3)Cl),during the *** the reaction progressed,these new species agglomerated,leading to a gradual loss of catalyst ***,the deactivated catalyst was successfully reactivated using a simple alkaline washing method.

关键词： CFC-113 Hydrodechlorination Chlorotrifluoroethylene Catalyst deactivation

Wetting front migration model of ion-adsorption rare earth during the multi-hole unsaturated liquid injection

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第2期16卷 483-496页

作者： Yu wang Xiaojun wang Yuchen Qiu Hao wang Gang li Kaijian Hu wen Zhong Zhongqun Guo Bing li Chunlei Zhang Guangxiang Ye Jiangxi Key Laboratory of Mining Engineering Jiangxi University of Science and TechnologyGanzhou341000China School of Resources and Environment Engineering Jiangxi University of Science and TechnologyGanzhou341000China School of Civil Engineering and Surveying&Mapping Engineering Jiangxi University of Science and TechnologyGanzhou341000China Ganzhou Nonferrous Metallurgy Research Institute Ganzhou341000China

In the process of ion-adsorption rare earth ore leaching,the migration characteristics of the wetting front in multi-hole injection holes and the influence of wetting front intersection effect on the migration distance of wetting fronts are still ***,wetting front migration distance and leaching time are usually required to optimize the leaching *** this study,wetting front migration tests of ionadsorption rare earth ores during the multi-hole fluid injection(the spacing between injection holes was 10 cm,12 cm and 14 cm)and single-hole fluid injection were completed under the constant water head *** the pre-intersection stage,the wetting front migration laws of ion-adsorption rare earth ores during the multi-hole fluid injection and single-hole fluid injection were *** the postintersection stage,the intersection accelerated the wetting front *** using the Darcy’s law,the intersection effect of wetting fronts during the multi-hole liquid injection was transformed into the water head height directly above the ***,based on the Green-Ampt model,a wetting front migration model of ion-adsorption rare earth ores during the multi-hole unsaturated liquid injection was *** analysis results showed that the proposed model can accurately simulate the infiltration process under experimental *** research results enrich the infiltration law and theory of ion-adsorption rare earth ores during the multi-hole liquid injection,and this study provides a scientific basis for optimizing the liquid injection well pattern parameters of ion-adsorption rare earth in situ leaching in the future.

关键词： Ion-adsorption rare earth ore Multi-hole unsaturated liquid injection In situ leaching Intersection effect Calculation model

Single-Component Color-Tunable Smart Organic Emitters with Simultaneous Multistage Stimuli-Responsiveness and Multimode Emissions

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Research 2024年第2期2023卷 719-728页

作者： Yu Yan Chengfang liu Jianzhong Fan Yusheng li Huanling liu Qian wang Xiangchun lil Junfeng li wen-Yong Lai State Key Laboratory of Organic Electronics and Information Displays(SKLOEID) Institute of Advanced Materials(IAM)School of Chemistry and Life SciencesNanjing University of Posts&Telecommunications9 Wenyuan RoadNanjng 210023China Shandong Province Key Laboratory of Medical Physics and Image Processing Technology School of Physics and ElectronicsShandong Normal UniversityJinan 250358China

Achieving color-tunable emission in single-component organic emitters with multistage stimuli-responsiveness is of vital significance for intelligent optoelectronic applications,but remains enormously ***,we present an unprecedented example of a color-tunable single-component smart organic emitter(DDOP)that simultaneously exhibits multistage stimuli-responsiveness and multimode *** based on a highly twisted amide-bridged donor-tcceptor-donor structure has been found to facilitate intersystem crossing,form multimode emissions,and generate multiple emissive species with multistage *** pristine crystalline powders exhibit abnormal excitation-dependent emissions from a monomer-dominated blue emission centered at 470 nm to a dimer-dominated yellow emission centered at 550 nm through decreasing the ultraviolet(UV)excitation wavelengths,whereas DDOP single crystals show a wide emission band with a main emission peak at 585 nm when excited at different *** emission behaviors of pristine crystalline powders and single crystals are different,demonstrating emission features that are closely related to the aggregation *** work has developed color-tunable single-component organic emitters with simultaneous multistage stimuli-responsiveness and multimode emissions,which is vital for expanding intelligent optoelectronic applications,including multilevel information encryption,multicolor emissive patterns,and visual monitoring of UV wavelengths.

关键词： donor excitation Smart

Magnetic-field-assisted triboelectric nanogenerator for harvesting multi-directional wave energy

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Nano Research 2024年第8期17卷 7144-7152页

作者： Mengru Ding Jianlong wang Da Zhao Hengyu li Xiaojun Cheng Jianming wen Zhong lin wang Tinghai Cheng Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of SciencesBeijing 101400China School of Nanoscience and Engineering University of Chinese Academy of SciencesBeijing 100049China Guangzhou Institute of Blue Energy Guangzhou 510555China College of Engineering Zhejiang Normal UniversityJinhua 321004China School of Materials Science and Engineering Georgia Institute of TechnologyAtlantaGA 30332-0245USA

Ocean wave energy is a significant and promising source of renewable ***,the energy harvesting is challenging due to the multi-directional nature of *** paper proposes a magnetic-field-assisted triboelectric nanogenerator(MFATENG)for harvesting multi-directional wave *** incorporating a magnetic field,the planar motion of the pendulum is converted into spatial motion,increasing the triggering of multilayered TENG(M-TENG)and enhancing the output energy of the *** results demonstrate that the output energy of the MFA-TENG is increased by 73%by utilizing the magnetic ***,a spring model based on the origami-structured M-TENG is established to analyze the effect of different equivalent stiffnesses on the performance of the M-TENG,aiming to obtain optimal output *** results showcase the impressive output performance of the M-TENG,generating outputs of 250 V,18μA,and 255 ***,the proposed MFA-TENG effectively harvests multi-directional wave energy under water-wave driven *** study significantly enhances the ability of the MFA-TENG to harvest multi-directional wave energy and presents a promising approach for self-powered marine monitoring in the future.

关键词： triboelectric nanogenerator magnetic-field-assisted spring model multi-directional wave energy

Icariin plus curcumol enhances autophagy through the mTOR pathway and promotes cathepsin B-mediated pyroptosis of prostate cancer cells

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Asian Pacific Journal of Tropical Biomedicine 2024年第2期14卷 55-64页

作者： Xu-Yun wang wen-Jing Xu Bo-Nan li Tian-Song Sun wen Sheng Department of Andrology Beijing Hospital of Traditional Chinese MedicineCapital Medical UniversityBeijing100010China Department of Dermatology The First Affiliated Hospital of Hunan University of Chinese MedicineChangsha410021China School of Integrated Chinese and Western Medicine Hunan University of Chinese MedicineChangsha410208China Andrology Laboratory Hunan University of Chinese MedicineChangsha410208China School of Rehabilitation Medicine and Health Care Hunan University of MedicineHuaihua418000China School of Traditional Chinese Medicine Hunan University of MedicineHuaihua418000China

Objective:To examine the effect of icariin plus curcumol on prostate cancer cells PC3 and elucidate the underlying ***:We employed the Cell Counting Kit 8 assay and colony formation assay to assess cell viability and *** expression was analyzed using monodansylcadaverine *** and Western blot analyses were used to evaluate protein expressions related to autophagy,pyroptosis,and the mTOR *** damage was examined using the lactate dehydrogenase ***,cathepsin B and NLRP3 were detected by ***:Icariin plus curcumol led to a decrease in PC3 cell proliferation and an enhancement of *** levels of LC3-Ⅱ/LC3-Ⅰand beclin-1 were increased,while the levels of p62 and mTOR were decreased after treatment with icariin plus *** changes were reversed upon overexpression of ***,3-methyladenine resulted in a decrease in inflammatory cytokines,pyroptosis-related protein levels,and lactate dehydrogenase concentration,compared to the icariin plus curcumol *** cathepsin B reversed the regulatory effects of icariin plus ***:Icariin plus curcumol demonstrates great potential as a therapeutic agent for castration-resistant prostate cancer by enhancing autophagy via the mTOR pathway and promoting pyroptosis mediated by cathepsin *** findings provide valuable insights into the molecular mechanisms underlying the therapeutic potential of icariin and curcumol for prostate cancer treatment.

关键词： Icariin Curcumol Autophagy mTOR Cathepsin B Pyroptosis Prostate cancer

Construction of core@double-shell structured energetic composites with simultaneously enhanced thermal stability and safety performance

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Defence Technology（防务技术） 2024年第4期34卷 134-142页

作者： Peng wang wen Qian Ruolei Zhong Fangfang He Xin li Jie Chen li Meng Yinshuang Sun Guansong He Institute of Chemical Materials China Academy of Engineering PhysicsMianyang 621900China State Key Laboratory of Environment-friendly Energy Materials School of Materials and ChemistrySouthwest University of Science and TechnologyMianyang 621010China

The poor thermal stability and high sensitivity severely hinder the practical application of hexanitrohexaazaisowurtzitane(CL-20).Herein,a kind of novel core@double-shell CL-20 based energetic composites were fabricated to address the above *** coordination complexes which consist of natural polyphenol tannic acid(TA) and Fe~Ⅲ were chosen to construct the inner shell,while the graphene sheets were used to build the outer *** resulting CL-20/TA-Fe~Ⅲ/graphene composites exhibited simultaneously improved thermal stability and safety performance with only 1 wt% double-shell content,which should be ascribed to the intense physical encapsulation effect from inner shell combined with the desensitization effect of carbon nano-materials from outer *** phase transition(ε to γ) temperature increased from 173.70 ℃ of pure CL-20 to 191.87℃ of CL-20/TA-Fe~Ⅲ/graphene ***,the characteristic drop height(H_(50)) dramatically increased from 14.7 cm of pure CL-20 to112.8 cm of CL-20/TA-Fe~Ⅲ/graphene composites,indicating much superior safety performance after the construction of the double-shell *** general,this work has provided an effective and versatile strategy to conquer the thermal stability and safety issues of CL-20 and contributes to the future application of high energy density energetic materials.

关键词： CL-20 Double-shell structure Thermal stability Safety performance Tannic acid Graphene sheets