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Process-driven susceptibility assessment of glacial lake outburst debris flow in the Himalayas under climate change

Advances in Climate Change Research 2024年第3期15卷 500-514页

作者： Bin ZHOU Qiang ZOU hu JIANG Tao YANG Wen-Tao ZHOU Si-yu CHEN Hong-Kun YAO institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China University of chinese academy of sciences Beijing 100049China School of Environment and Resource Southwest University of Science and TechnologyMianyang 621010China

Global warming is causing glaciers to retreat and glacial lakes to expand in the Himalayas,which amplifies the risk of glacial lake outburst debris flows(GLODFs)and poses a significant threat to downstream lives and ***,the complex interplay between GLODF occurrences and associated indicators,coupled with the lack of a comprehensive susceptibility indicator system that considers the entire GLODF process,presents a substantial challenge in assessing GLODF susceptibility in the *** study proposes a process-driven GLODF susceptibility assessment indicator system responding to climate change that considers the complete process of GLODF formation,incorporating relevant parameters about upstream,themselves,and downstream of glacial ***,to mitigate subjective factors associated with traditional evaluation methods,we developed three novel hybrid machine-learning models by integrating classic machine-learning algorithms with the whale optimization algorithm(WOA)to delineate the distribution of GLODF susceptibility in the *** the hybrid models effectively predicted the GLODFs occurrence,with the WOA-SVC model demonstrating the highest prediction *** 3.%of the catchments exhibit high and very high susceptibility levels,primarily concentrated along the north and south sides of the Himalayan ridge,particularly in the eastern and central *** capturing the physical formation process of hazards,such as topographic potential(highest relative importance value of 40%),can precisely identify GLODF.A total of 128 catchments pose potential transboundary threats,with 24 classified as having a very high susceptibility level and 25 as having a high susceptibility ***,the border region between China and Nepal is a prominent hotspot for transboundary threats of *** findings can provide valuable clues for disaster prevention,mitigation,and cross-border coordination in the Himalayas.

关键词： Glacial lake outburst debris flow Susceptibility assessment Climate change Himalayas

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Phase transfer-based high-efficiency recycling of precious metal electrocatalysts

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Green Chemical Engineering 2024年第1期5卷 68-74页

作者： Qing Zeng Shaonan Tian yu Zhang hui Liu Dong Chen Xinlong Tian Chaoquan hu Jun Yang State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing100190China State Key Laboratory of Marine Resource Utilization in South China Sea Hainan Provincial Key Lab of Fine ChemistrySchool of Chemical Engineering and TechnologyHainan UniversityHaikou570228China Nanjing IPE institute of Green Manufacturing Industry Nanjing211100China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing100049China

Recycling precious metals with high-efficiency is undoubtedly beneficial to optimize resource utilization for environmental remediation and sustainable ***,we report an efficient route to recycle the palladium(Pd)and platinum(Pt)electrocatalysts using a phase transfer *** strategy involves acidic dissolution of deactivated precious metal(Pd/Pt)electrocatalysts from their loading substrates,mixing with an ethanolic solution of dodecylamine(DDA),subsequent extraction of metal ions into a non-polar organic phase,and final reduction by sodium borohydride to reproduce high-performance electrocatalysts towards typical electrochemical reactions,e.g.,oxygen reduction reaction(ORR)and ethanol oxidation reaction(EOR).In specific,the transfer efficiencies are up to 98%and the final recovery rate is over 85%for Pd and Pt electrocatalysts in each *** approach symbolizes a facile and efficient way to recover precious metals,which might be applied to recycling a wide range of metals in various realms after appropriate modifications.

关键词： Precious metal Phase transfer Extraction Recovery Electrocatalyst

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NEW OPTICALLY ACTIVE AROMATIC POLYIMIDES Ⅱ: SYNTHESIS AND PROPERTIES OF OPTICALLY ACTIVE AROMATIC POLYIMIDE BASED ON (R)-(+)-2, 2′-BIS (2-TRIFLUORO-4-AMINOPHENOXY)-1, 1′-BINAPHTHYL

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chinese Journal of Polymer Science 1999年第1期17卷 87-90页

作者： Qi-ding Mi yu Ma Lian-xun Gao Meng-xian Ding Changchun institute of {3. Chemistry, chinese academy of sciences Changchun 13.022, China Department of Chemistry, Peking University, {3. 100871 中科院长春应用化学所吉林长春 130022 中科院长春应用化学所吉林长春

Optically active (R)-(+)-2, 2' -bis(2 -trifluoro-4 -aminophenoxy)- 1, 1' -binaphthyl was prepared from1, 1'-bi-2-naphthol. The optically active aromatic polyimide was also successfully synthesized. This newpolymer has good solubility, thermal stability etc. Its specific rotation was found to be +174°, and itschiroptical property was also studied.

关键词： Optical activity 1, 1′-Bi-2-naphthol, Polyimide

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Triplet-triplet annihilation upconversion materials as electrophoretic inks

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chinese Chemical Letters 2024年第3期35卷 439-442页

作者： Qiaoyu Zhang Guiwen Luo Jinping Chen Tianjun yu Rui hu Guoqiang Yang Yi Zeng Yi Li Key Laboratory of Photochemical Conversion and Optoelectronic Materials Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China Key Laboratory of Photochemistry Institute of ChemistryChinese Academy of SciencesBeijing 100190China University of chinese academy of sciences Beijing 100049China

Luminescent materials that can be reversibly switched by electric field stimulation are attractive since the potential application for optoelectronic *** we report a triplet-triplet annihilation upconversion(TTA-UC)system with electrophoretic response which is developed as the electrophoretic *** TTA-UC system consists of an ionic derivative of 9,10-diphenyl anthracene(DPA)as the annihilator and Pt(II)octaethylporphyrin(PtOEP)as the *** applying an electric field,migration and enrichment of positively charged DPA derivatives towards the cathode results in a 20%enhancement of TTA-UC.A quasi-solid film for electrically writing is made using the electrophoretic TTA system as the ink and a platinum electrode as a *** prototype of TTA-UC ink demonstrates unique luminescence functions upon electrically writing and erasing,providing a promising strategy to develop electronic devices for display,information storage and encryption.

关键词： Triplet-triplet annihilation Photon upconversion Electrophoresis Electrophoretic ink Luminescence display

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Cinobufotalin prevents bone loss induced by ovariectomy in mice through the BMPs/SMAD and Wnt/β-catenin signaling pathways

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Animal Models and Experimental Medicine 2024年第3期7卷 208-221页

作者： Da-zhuang Lu Li-jun Zeng Yang Li Ran-li Gu Meng-long hu Ping Zhang Peng yu {3. Zhang Zheng-wei Xie Hao Liu Yong-sheng Zhou Department of Prosthodontics Peking University School and Hospital of StomatologyBeijingChina National Center of Stomatology BeijingChina National Clinical Research Center for Oral Diseases BeijingChina beijing Key Laboratory of Digital Stomatology BeijingChina Department of Cariology and Endodontology Peking University School and Hospital of StomatologyBeijingChina Peking University International Cancer institute Peking University Health Science CenterPeking UniversityBeijingChina Central Laboratory Peking University School and Hospital of StomatologyBeijingChina National Engineering Research Center of Oral Biomaterials and Digital Medical Devices BeijingChina

Background:Osteoporosis is a chronic bone disease characterized by bone loss and decreased bone ***,current anti-resorptive drugs carry a risk of various *** deep learning-based efficacy prediction system(DLEPS)is a forecasting tool that can effectively compete in drug screening and prediction based on gene expression *** study aimed to explore the protective effect and potential mechanisms of cinobufotalin(CB),a traditional chinese medicine(TCM),on bone ***:DLEPS was employed for screening anti-osteoporotic agents according to gene profile changes in primary ***-CT,histological and morphological analysis were applied for the bone protective detection of CB,and the osteogenic differentiation/function in human bone marrow mesenchymal stem cells(hBMMSCs)were also *** underlying mechanism was verified using qRT-PCR,Western blot(WB),immunofluorescence(IF),***:A safe concentration(0.25mg/kg in vivo,0.05μM in vitro)of CB could effectively preserve bone mass in estrogen deficiency-induced bone loss and promote osteogenic differentiation/function of *** BMPs/SMAD and Wnt/β-catenin signaling pathways participated in CB-induced osteogenic differentiation,further regulating the expression of osteogenesis-associated factors,and ultimately promoting ***:Our study demonstrated that CB could significantly reverse estrogen deficiency-induced bone loss,further promoting osteogenic differentiation/function of hBMMSCs,with BMPs/SMAD and Wnt/β-catenin signaling pathways involved.

关键词： BMPs/SMAD bone loss cinobufotalin hBMMSCs osteogenesis osteoporosis Wnt/β-catenin signaling pathways

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Adhesion property of AlCrNbSiTi high-entropy alloy coating on zirconium:experimental and theoretical studies

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Nuclear Science and Techniques 2024年第8期35卷 79-91页

作者： Bao‑Liang Zhang Wen‑Guan Liu Meng‑He Tu Can Fang Yan Liu yu‑hui Wang Yong hu hui Wang China institute of Atomic Energy Beijing 102413China Sino‑French institute of Nuclear Engineering and Technology Sun Yat-Sen UniversityZhuhai 519082China School of Power and Mechanical Engineering Wuhan UniversityWuhan 430072China

Experimental scratch tests and first-principles calculations were used to investigate the adhesion property of AlCrNbSiTi high-entropy alloy(HEA)coatings on zirconium *** HEA and Cr coatings were deposited on Zr alloy substrates using multi-arc ion plating technology,and scratch tests were subsequently conducted to estimate the adhesion property of the *** results indicated that Cr coatings had better adhesion strength than HEA coatings,and the HEA coatings showed *** special quasi-random structure approach was used to build HEA models,and Cr/Zr and HEA/Zr interface models were employed to investigate the cohesion between the coatings and Zr substrate using first-principles *** calculated interface energies showed that the cohesion between the Cr coating and the Zr substrate was stronger than that of the HEA coating with *** contrary to Al or Si in the HEA coating,Cr,Nb,and Ti atoms binded strongly with Zr *** on the calculated elastic constants,it was found that low Cr and high Al content decreased the mechanical performances of HEA ***,this study demonstrated the utilization of a combined approach involving first-principles calculations and experimental studies for future HEA coating development.

关键词： High-entropy alloy coating Cr coating Adhesion property Scratch test First-principles calculation

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cDNA cloning, expression and antibacterial activity of lysozyme C in the blue shrimp (Litopenaeus stylirostris)

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Progress in Natural Science:Materials International 2009年第7期19卷 837-844页

作者： Weijun Mai a,b, Chaoqun hu a, a applied Marine Biology Laboratory, South China Sea institute of Oceanology, Science {3. of China, Guangzhou 5103.1, China b Graduate University of{3., beijing 100049, China [a]applied Marine Biology Laboratory South China Sea Institute of Oceanology Science Academy of China Guangzhou 510301 China [b]Graduate University of Chinese Academy of Sciences Beijing 100049 China

The gene coding for lysozyme in blue shrimp (Litopenaeus stylirostris) was cloned, sequenced and expressed in pET-3.a vector. The deduced amino acid sequence of F. merguiensi lysozyme showed 3.–93. similarity with the mouse, human, chicken, and tiger prawn counterparts. The lysozyme was purified to homogeneity and observed as a band of approximately 15 kDa in 15% SDS–PAGE. Semiquantitative RT-PCR analysis demonstrated that mRNA transcripts of lysozyme could be mainly detected in the tissues of haemocytes, gill, gonad and the lymphoid organ of unchallenged shrimps, whereas the expression of lysozyme transcripts was increased in all the tested tissues after the heat-killed Vibrio alginolyticus challenge. The temporal expression of lysozyme mRNA in haemolymph challenged by Micrococcus luteus and V. alginolyticus was both up-regulated and reached the maximum level at 8 and 16 h post-stimulation, respectively, and then dropped back to the original level. Bacteriolytic activity of the lysozyme against different bacterial cultures was determined by the solid phase and turbidimetric assays. The results demonstrated that the lysozyme we obtained was not only against Grampositive and Gram-negative bacteria but also against shrimp pathogens V. alginolyticus and V. parahemolyticus. In addition, the study of the inhibition mechanism revealed that the antibacterial activity of the lysozyme was a result of the bactericidal effect.

关键词： Lysozyme C Litopenaeus stylirostris PCR-cloning Expression Antibacterial activity

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Characteristic Rainfall for Warning of Debris Flows

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Journal of Mountain Science 2010年第3期7卷 207-214页

作者： hu Kaiheng Cui Peng Wang Chuanchang Li Yong Lu xiaobing Key Laboratory of Mountain Hazards and Earth Surface Processes Chinese Academy of Sciences Chengdu 610041 China institute of Mountain Hazards and Environment Chinese Academy of Sciences & Ministry of Water Conservancy Chengdu 610041 China institute of Mechanics Chinese Academy of Sciences Beijing 100080 China

A characteristic rainfall is introduced to overcome the difficulties encountered in determining a critical rainfall value for triggering debris *** characteristic value is defined as the rainfall at which debris-flow occurrence probability shows a rapid increase,and can be used as a warning rainfall threshold for debris *** of recorded debris flows and 24-hour rainfall data at Jiangjia basin,yunnan Province,in southwestern China,demonstrates the existence of such a characteristic *** was found that the characteristic rainfall corresponds to the daily rainfall of 90% cumulative probability by analyzing the basin's daily rainfall *** result provides a simple and useful method for estimating a debris-flow warning rainfall threshold from the daily rainfall *** was applied to estimate the debris-flow warning rainfall threshold for the Subaohe basin,a watershed in the 2008 Wenchuan earthquake zone with many physical characteristics similar to those of the Jiangjia basin.

关键词： Debris flow Wenchuan earthquake warning rainfall threshold statistics of daily rainfalldistribution

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Coupling changes of soil functional gene abundances and extracellular enzyme activities across the diagnostic horizons of agricultural Isohumosols

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Pedosphere 2024年第3期34卷 540-552页

作者： Zhuxiu LIU Haidong GU xiaojing hu Zhenhua yu Yansheng LI Junjie LIU Jian JIN xiaobing LIU Guanghua WANG State Key Laboratory of Black Soils Conservation and Utilization Northeast Institute of Geography and AgroecologyChinese Academy of SciencesHarbin 150081(China) University of chinese academy of sciences Beijing 100049(China)

Soil functional microbial taxa and extracellular enzymes are involved in a variety of biogeochemical cycling *** many studies have revealed the vertical change patterns of microbial communities along soil profile,the general understanding of the coupling changes in the functional gene abundances(FGAs)and extracellular enzyme activities(EEAs)in soil profiles is still limited,which hinders us from revealing soil ecosystem ***,we comparatively investigated the FGAs and EEAs in the diagnostic A,B,and C horizons of soil profiles obtained from two suborders of Isohumosols(Mollisols),Ustic and Udic Isohumosols,in Northeast China based on quantitative real-time polymerase chain reaction and standard fluorometric techniques,*** distribution patterns of both FGAs and EEAs significantly distinguished by the two soil suborders and were also separated from A to C ***,the variations of EEAs and FGAs were greater in Udic Isohumosols compared to Ustic Isohumosols along soil profiles,and greater changes were observed in C horizon than in A *** FGAs and EEAs correspondently decreased along the soil ***,when normalized by soil organic carbon,the specific EEAs significantly increased in deep soil horizons,suggesting that microorganisms will input more resources to the production of enzymes to ensure microbial nutrient requirements under resource *** importantly,we revealed that soil microbial nutrient demands were limited by carbon(C)and phosphorus(P),and the C and P limitations significantly increased along soil profiles with a greater C limitation observed in Ustic Isohumosols than in Udic ***,our findings provided solid evidence showing the links between FGAs,EEAs,and microbial nutrient limitations,which would be helpful for a better understanding of the ecosystem processes in soil profiles.

关键词： ecoenzymatic stoichiometry microbial nutrient limitation microbial nutrient requirement Mollisols soil ecosystem process soil profile

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(+)/(-)-Gerbeloid A,a pair of unprecedented coumarin-based polycyclic meroterpenoid enantiomers from Gerbera piloselloides:Structural elucidation,semi-synthesis,and lipid-lowering activity

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Acta Pharmaceutica Sinica B 2024年第6期14卷 2657-2668页

作者： Chenxu Zhao Jingrong Li yue hu Lingyu Li Meng yu yunfeng huang Tao Zhang Hai Shang Zhongmei Zou State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Medicinal Plant DevelopmentChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100193China institute of chinese Medicine Resources Guangxi Institute of Chinese Medicine&Pharmaceutical ScienceNanning 530000China

A pair of coumarin-based polycyclic meroterpenoid enantiomers(+)/(-)-gerbeloid A[(+)-1a and(-)-1b]were isolated from the medicinal plant Gerbera piloselloides,which have a unique caged oxatricyclo[4.***.2.0^(3.8)]decene *** planar and three-dimensional structures were exhaustively characterized by comprehensive spectroscopic data and X-ray diffraction *** by the hypothetical biosynthetic pathway,the biomimetic synthesis of racemic 1 was achieved using 4-hydroxy-5-methylcoumarin and citral as the starting material via oxa-6πelectrocyclization and intramolecular[2+2]***,the results of the biological activity assay demonstrated that both(+)-1a and(-)-1b exhibited potent lipid-lowering effects in 3.3.L1 adipocytes and the high-fat diet zebrafish ***,the lipid-lowering activity of(+)-1a is better than that of(-)-1b at the same concentration,and molecular mechanism study has shown that(+)-1a and(-)-1b impairs adipocyte differentiation and stimulate lipolysis by regulating C/EBPα/PPARγsignaling and Perilipin signaling in vitro and in *** findings provide a promising drug model molecule for the treatment of obesity.

关键词： Gerbera piloselloides Natural products Coumarin meroterpenoid Structural elucidation Biomimetic synthesis Lipid-lowering activity 3.3.L1 adipocytes High-fat diet zebrafish model

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