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Numerical investigation of hydro-morphodynamic characteristics of a cascading failure of landslide dams

Journal of Mountain Science 2024年第6期21卷 1868-1885页

作者： ZHONG Qiming CHEN Lingchun mei Shengyao SHAN Yibo wu Hao ZHAO Kunpeng Department of Geotechnical Engineering Nanjing Hydraulic Research InstituteNanjing 210024China National Key Laboratory of Water Disaster Prevention Nanjing 210098China Key Laboratory of Reservoir and Dam Safety of the Ministry of Water Resources Nanjing 210029China

A cascading failure of landslide dams caused by strong earthquakes or torrential rains in mountainous river valleys can pose great threats to people’s lives,properties,and *** this study,based on the three-dimensional Reynoldsaveraged Navier-Stokes equations(RANS),the renormalization group(RNG)k-εturbulence model,suspended and bed load transport equations,and the instability discriminant formula of dam breach side slope,and the explicit finite volume method(FVM),a detailed numerical simulation model for calculating the hydro-morphodynamic characteristics of cascading dam breach process has been *** developed numerical model can simulate the breach hydrograph and the dam breach morphology evolution during the cascading failure process of landslide dams.A model test of the breaches of two cascading landslide dams has been used as the validation *** comparison of the calculated and measured results indicates that the breach hydrograph and the breach morphology evolution process of the upstream and downstream dams are generally consistent with each other,and the relative errors of the key breaching parameters,i.e.,the peak breach flow and the time to peak of each dam,are less than±5%.Further,the comparison of the breach hydrographs of the upstream and downstream dams shows that there is an amplification effect of the breach flood on the cascading landslide dam *** key parameters,i.e.,the distance between the upstream and the downstream dams,the river channel slope,and the downstream dam height,have been used to study the flood amplification *** parameter sensitivity analyses show that the peak breach flow at the downstream dam decreases with increasing distance between the upstream and the downstream dams,and the downstream dam ***,the peak breach flow at the downstream dam first increases and then decreases with steepening of the river channel *** the flood caused by the upstream dam failure flows to the

关键词： Cascading landslide dams Cascading dam failure process Detailed numerical simulation model Flood amplification effect Parameter sensitivity analyses

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Experimental Study on the Axial Compression Performance of Bamboo Scrimber Columns Embedded with Steel Reinforcing Bars

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Structural Durability & Health Monitoring 2024年第6期18卷 805-833页

作者： Xueyan Lin Mingtao wu Guodong Li Nan Guo Lidan mei College of Civil Engineering and Transportation Northeast Forestry UniversityHarbin150000China Department of Building Engineering College of Civil EngineeringTongji UniversityShanghai200092China College of Transportation and Civil Engineering Fujian Agriculture and Forestry UniversityFuzhou350002China

In this paper,a new type of bamboo scrimber column embedded with steel bars(rebars)was proposed,and the compression performance was improved by pre-embedding rebars during the preparation of the *** effects of the slenderness ratio and the reinforcement ratio on the axial compression performance of reinforced bamboo scrimber columns were studied by axial compression tests on 28 *** results showed that the increase in the slenderness ratio had a significant negative effect on the axial compression performance of the *** the slenderness ratio increased from 19.63 to 51.96,the failure mode changed from strength failure to buckling failure,and the maximum bearing capacity decreased by 43.03%.The axial compression performance of the reinforced bamboo scrimber columns did not significantly improve at a slenderness ratio of 19.63,but the opposite was true at slenderness ratios of 36.95 and *** the reinforcement ratio increased from 0%to 4.52%,the bearing capacity of those with a slenderness ratio of 51.96 increased by up to 16.99%,and the stiffness and ductility were also ***,based on existing specifications,two modification parameters,the overall elastic modulus Ec and the combined strength fcc,were introduced to establish a calculation method for the bearing capacity of the reinforced bamboo scrimber *** calculation results were compared with the test results,and the results showed that the proposed calculation models can more accurately predict the bearing capacity.

关键词： Bamboo scrimber column steel bar axial compression performance theoretical model

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Multiple factors influencing high-purity indium electrolytic refining

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Chinese Journal of Chemical Engineering 2024年第7期71卷 148-160页

作者： Hong-Qiang Fan Fei Li Hong-Xing Zheng wu-ji Pan mei-Zhen wu Yashar Behnamian Ju-Bo Peng Dong-Hai Lin State Key Laboratory of Advanced Special Steel&School of Materials Science and Engineering Shanghai UniversityShanghai 200444China Shanghai Engineering Research Center for Integrated Circuits and Advanced Display Materials Shanghai UniversityShanghai 200444China Research&Development Center Yunnan Tin Group(Holding)Limited CompanyKunming 650032China Department of Chemical and Materials Engineering University of AlbertaEdmonton T6G 2V4AlbertaCanada School of Energy and Materials Shanghai Key Laboratory of Engineering Materials Application and EvaluationShanghai Polytechnic UniversityShanghai 201209China

The effects of various contaminants in the electrolytic refinement of indium were investigated using a glow discharge mass spectrometer(GDMS).The effects of several factors such as the indium ion(In3+)concentration,the sodium chloride(NaCl)concentration,the current density,the gelatin concentration,the pH,and the electrode distance,were *** variations in impurity levels concerning gelatin concentration were *** the gelatin and In3+concentration were moderately positively correlated with the Pb *** Sb concentration was associated positively with the NaCl concentration,while the Ti concentration had an adverse correlation with the NaCl *** Bi element content was positively linked to the electrode *** the current density increased,Cu,Pb,and Bi impurities initially rose and then eventually ***,a critical current density of 45 A·m^(-2) was identified in this behavior.

关键词： High-purity indium Electrolysis Multiple factors Electrochemistry Purification

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Association between central serous chorioretinopathy and Helicobacter pylori infection: a systematic review and Meta-analysis

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International Journal of Ophthalmology(English edition) 2024年第6期17卷 1120-1127页

作者： Da-Wen wu Fei-Peng Jiang Ge Ge mei-Xia Zhang Department of Ophthalmology West China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina Research Laboratory of Macular Disease West China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina

AIM:To investigate the association between central serous chorioretinopathy(CSC)and Helicobacter pylori(Hp)by summarizing all available ***:The Scopus,Embase,EBSCO,PubMed,Web of Science,and Cochrane Library databases for all relevant studies published from inception to October 2022 were searched,and manually searched for relevant reference lists as a *** investigating the association between CSC and Hp infection were ***,8 case-control studies were included in the Meta-analysis after study ***:The results showed no significant correlation between Hp infection and CSC[odds ratio(OR)1.89,95%confidential interval(CI)0.58–6.15,I2=96%,P=0.29].After subgroup analysis based on the degree of development of the study(developing/developed countries),it was found that the results of the two subgroups were the same as the whole,and no significant difference between the two subgroups ***-regression showed that the effect of sample size on heterogeneity among studies was more prominent(P<0.01,adjusted R^(2)=89.72%),which can explain 89.72%of the sources of ***:This Meta-analysis reveals no significant correlation between Hp infection and CSC,which still warrants further well-designed extensive sample studies to reach a more reliable conclusion and promote a better understanding of the treatment of CSC.

关键词： central serous chorioretinopathy Helicobacter pylori infection retinal diseases Meta-analysis

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CAEFusion: A New Convolutional Autoencoder-Based Infrared and Visible Light Image Fusion Algorithm

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Computers, Materials & Continua 2024年第8期80卷 2857-2872页

作者： Chun-Ming wu mei-Ling Ren Jin Lei Zi-Mu Jiang Key Laboratory of Modern Power System Simulation and Control&Renewable Energy Technology Ministry of EducationSchool of Electrical EngineeringNortheast Electric Power UniversityJilin132012China School of Electrical Engineering Northeast Electric Power UniversityJilin132012China School of Electronic Information Engineering Bozhou UniversityBozhou236800China

To address the issues of incomplete information,blurred details,loss of details,and insufficient contrast in infrared and visible image fusion,an image fusion algorithm based on a convolutional autoencoder is *** region attention module is meant to extract the background feature map based on the distinct properties of the background feature map and the detail feature map.A multi-scale convolution attention module is suggested to enhance the communication of feature *** the same time,the feature transformation module is introduced to learn more robust feature representations,aiming to preserve the integrity of image *** study uses three available datasets from TNO,FLIR,and NIR to perform thorough quantitative and qualitative trials with five additional *** methods are assessed based on four indicators:information entropy(EN),standard deviation(SD),spatial frequency(SF),and average gradient(AG).Object detection experiments were done on the M3FD dataset to further verify the algorithm’s performance in comparison with five other *** algorithm’s accuracy was evaluated using the mean average precision at a threshold of 0.5(mAP@0.5)*** experimental findings show that CAEFusion performs well in subjective visual and objective evaluation criteria and has promising potential in downstream object detection tasks.

关键词： Image fusion deep learning auto-encoder(AE) infrared visible light

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Responses of plant diversity and soil microorganism diversity to nitrogen addition in the desert steppe,China

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Journal of Arid Land 2024年第3期16卷 447-459页

作者： YE He HONG mei XU Xuehui LIANG Zhiwei JIANG Na TU Nare wu Zhendan College of Grassland Resources and EnvironmentInner Mongolia Agricultural UniversityInner Mongolia Key Laboratory of Soil Quality and Nutrient ResourcesHohhot 010018China Key Laboratory of Agricultural Ecological Security and Green Development at University of Inner Mongolia Hohhot 010018China

Nitrogen(N)deposition is a significant aspect of global change and poses a threat to terrestrial *** impact of plant-soil microbe relationships to N deposition has recently attracted considerable *** microorganisms have been proven to provide nutrients for specific plant growth,especially in nutrient-poor desert steppe ***,the effects of N deposition on plant-soil microbial community interactions in such ecosystems remain poorly *** investigate these effects,we conducted a 6-year N-addition field experiment in a Stipa breviflora *** steppe in Inner Mongolia Autonomous Region,*** N treatment levels(N0,N30,N50,and N100,corresponding to 0,30,50,and 100 kg N/(hm2•a),respectively)were applied to simulate atmospheric N *** results showed that N deposition did not significantly affect the aboveground biomass of desert steppe plants.N deposition did not significantly reduce the alfa-diversity of plant and microbial communities in the desert steppe,and low and mediate N additions(N30 and N50)had a promoting effect on *** variation pattern of plant Shannon index was consistent with that of the soil bacterial Chao1 index.N deposition significantly affected the beta-diversity of plants and soil bacteria,but did not significantly affect fungal *** conclusion,N deposition led to co-evolution between desert steppe plants and soil bacterial communities,while fungal communities exhibited strong stability and did not undergo significant *** findings help clarify atmospheric N deposition effects on the ecological health and function of the desert steppe.

关键词： soil microorganisms plant-microbial community interaction plant diversity nitrogen deposition desert steppe

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VMMAO-YOLO:an ultra-lightweight and scale-aware detector for real-time defect detection of avionics thermistor wire solder joints

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Frontiers of Mechanical Engineering 2024年第3期19卷 77-92页

作者： Xiaoqi YANG Xingyue LIU Qian wu Guojun WEN Shuang mei Guanglan LIAO Tielin SHI School of Mechanical Engineering and Electronic Information China University of GeosciencesWuhan 430074China State Key Laboratory of Digital Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China

The quality of the exposed avionics solder joints has a significant impact on the stable operation of the inorbit ***,the previously reported inspection methods for multi-scale solder joint defects generally suffer low accuracy and slow detection ***,a novel real-time detector VMMAO-YOLO is demonstrated based on variable multi-scale concurrency and multi-depth aggregation network(VMMANet)backbone and“one-stop”global information gather-distribute(OS-GD)*** with infrared thermography technology,it can achieve fast and high-precision detection of both internal and external solder joint ***,VMMANet is designed for efficient multi-scale feature extraction,which mainly comprises variable multi-scale feature concurrency(VMC)and multi-depth feature aggregation-alignment(MAA)*** can extract multi-scale features via multiple fix-sized and deformable convolutions,while MAA can aggregate and align multi-depth features on the same order for feature *** allows the low-level features with more spatial details to be transmitted in depth-wise,enabling the deeper network to selectively utilize the preceding inference *** VMMANet replaces inefficient highdensity deep convolution by increasing the width of intermediate feature levels,leading to a salient decline in *** OS-GD is developed for efficacious feature extraction,aggregation and distribution,further enhancing the global information gather and deployment capability of the *** a self-made solder joint image data set,the VMMAOYOLO achieves a mean average precision mAP@0.5 of 91.6%,surpassing all the mainstream YOLO-series ***,the VMMAO-YOLO has a body size of merely 19.3 MB and a detection speed up to 119 frame per second,far superior to the prevalent YOLO-series detectors.

关键词： defect detection of solder joints VMMAO-YOLO ultra-lightweight and high-performance multiscale feature extraction VMC and MAA modules OS-GD

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Experience of Drug Abusers Participating in Community-Based Drug Rehabilitation Services Provided by the Counselling Centres for Psychotropic Substance Abusers (CCPSAs) in Hong Kong

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Health 2020年第8期12卷 1008-1028页

作者： Mimi mei Ha Tiu Carmen Ka Man Fung Wing Yan Fung Yin Yee Lai Chui Man Tse Tsz Hung Wong Tsz Kwan Wong Wing Yi Wong mei suet wu Ka Man Yeung Lok Tung Yeung Yuk Ying Yu School of Nursing and Health Studies The Open University of Hong Kong HKSAR China

Despite the official statistics showing that the number of drug users has been declining, the problem of drug abuse remains serious in Hong Kong. This problem is evidenced by the trend of hidden and prolonged drug abuse. The recovery of drug abusers is an important process, because the misuse of drugs can cause many bio-psycho-social complications. Therefore, 11 Counselling Centres for Psychotropic Substance Abusers (CCPSAs) in different districts in Hong Kong play an important role on those drug abusers [1]. As a core community-based drug rehabilitation service in Hong Kong, studies about CCPSAs are limited. This study uses a descriptive qualitative approach to explore the experience of drug abusers participating in community-based drug rehabilitation services provided by CCPSAs. Five CCPSA users, who utilized the services for more than two months, participated in the semi-structured face-to-face interviews. Data collected were then analysed by thematic analysis, and five themes were generated: 1) receiving supportive counselling service in CCPSAs, 2) revealing variance towards nonmandatory services in CCPSAs, 3) encountering intrapersonal conflicts when participating in CCPSAs, 4) expanding social network through integration in group activities and 5) wishing to be a companion to other drug abusers. Findings of this study provide valuable insights towards services modification and the enhancement of drug rehabilitation and drug abusers’ wellbeing over the collaboration of healthcare workers, services providers and the media. However, this study has some limitations, and it presents suggestions for future research.

关键词： Drug Rehabilitation Services Counselling Centres Substances Abusers

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Multiple thermal events recorded in the Acasta Gneiss Complex:Evidence from in-situ dating of zircon, titanite, and apatite

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Science China Earth Sciences 2024年第3期67卷 673-686页

作者： Qingfeng mei Jinhui YANG Jinfeng SUN Qiuli LI Shitou wu Xiaoxiao LING Peng PENG Hao WANG State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Computational Geodynamics University of Chinese Academy of SciencesBeijing 100049China

In-situ dating of the zircons, titanites, and apatites in the rock fragments of approximately 1 cm2in size from the Acasta Gneiss Complex was performed using secondary ion mass spectrometry or laser ablation inductively coupled plasma mass spectrometry to provide constraints on the thermal history of the Acasta Gneiss Complex. The zircons in these rock fragments typically exhibit multiple age populations, reflecting the presence of inherited zircons or the post-crystallization process of zircon overgrowth. Combined with previous studies, our zircon dating results reveal multiple magmatic events that occurred in the Acasta Gneiss Complex, specifically at >3.96, ~3.72, and ~3.57 Ga, respectively. A titanite Pb-Pb isochron age of2911±22 Ma(95% confidence level, MSWD=1.5) for sample AY199 is identified, consistent with the timing of the latest Archean magmatism in the Acasta Gneiss Complex. The titanite U-Pb ages for samples AC478 and AY066 are 1932±270 Ma(95% confidence level, MSWD=2.3) and 1813±45 Ma(95% confidence level, MSWD=2.3), respectively. The apatites in sample P090803-C exhibit a Pb-Pb isochron age of 1833±26 Ma(95% confidence level, MSWD=1.4). The apatite U-Pb ages for samples AC478, AY199, and AY066 are 1850±20 Ma(95% confidence level, MSWD=1.3), 1827±100 Ma(95% confidence level, MSWD=6.3), and 1807±58 Ma(95% confidence level, MSWD=3.9), respectively. Titanites in samples AC478 and AY066, as well as the apatites in all four investigated samples, show a uniform age(Pb-Pb or U-Pb age) of ~1.9–1.8 Ga,indicating U-Pb system reset in these minerals due to the Wopmay orogeny and documenting that the peak temperature condition associated with the Wopmay orogeny exceeded the apatite U-Pb closure temperature and approached or exceeded that of titanite.

关键词： Zircon Titanite Apatite Acasta Gneiss Complex Wopmay Orogen

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Three New Hydroxytetradecenals from Amomum tsao-ko with Protein Tyrosine Phosphatase 1B and Glycogen Phosphorylase Inhibitory Activity

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Phyton-International Journal of Experimental Botany 2024年第5期93卷 875-883页

作者： Xiaolu Qin Xinyu Li Yi Yang mei Huang Shengli wu Pianchou Gongpan Lianzhang wu Juncai He Changan Geng State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunming650201China Nujiang Green Spice Industry Research Institute Lushui673100China University of Chinese Academy of Sciences Beijing100049China

The fruits of Amomum tsao-ko(Cao-Guo)were documented in Chinese Pharmacopoeia for the treatment of abdominal pain,vomiting,and *** our previous study,a series of diarylheptanes and flavonoids withα-glucosidase and protein tyrosine phosphatase 1B(PTP1B)inhibitory activity have been reported from the middle-polarity part of ***-ko,whereas the antidiabetic potency of the low-polarity constituents is still *** this study,three new hydroxytetradecenals,(2E,4E,8Z,11Z)-6R-hydroxytetradeca-2,4,8,11-tetraenal(1),(2E,4E,8Z)-6R-hydroxytetradeca-2,4,8-trienal(2)and(2E,4E)-6R-hydroxytetradeca-2,4-dienal(3)were obtained from the volatile oils of *** structures of compounds 1–3 were determined using spectroscopic data involving 1D and 2D nuclear magnetic resonance(NMR),high-resolution mass spectra(HRMS),and specific rotation([α]D).Their hypoglycemic activity was evaluated against glycogen phosphorylase(GPa)and *** 1 and 2 displayed moderate activity against PTP1B with inhibition rates of 33.8%−50.3%at 100 and 200μ***,compound 1 exhibited an obvious inhibitory effect on GPa(IC50=31.7μM),whereas compound 2 was *** study demonstrates hydroxytetradecenals as the characteristic components of ***-ko with therapeutic potential in diabetes.

关键词： Cao-Guo PTP1B and GPa inhibitors diabetes mellitus volatile oils

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