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Artificial neural network-based method for discriminating Compton scattering events in high-purity germaniumγ-ray spectrometer

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Nuclear Science and Techniques 2024年第2期35卷 64-84页

作者： Chun-Di fan Guo-Qiang Zeng Hao-wen Deng Lei Yan Jian Yang Chuan-Hao Hu Song Qing Yang Hou College of Nuclear Technology and Automation Engineering Chengdu University of TechnologyChengdu 610059China

To detect radioactive substances with low activity levels,an anticoincidence detector and a high-purity germanium(HPGe)detector are typically used simultaneously to suppress Compton scattering background,thereby resulting in an extremely low detection limit and improving the measurement ***,the complex and expensive hardware required does not facilitate the application or promotion of this ***,a method is proposed in this study to discriminate the digital waveform of pulse signals output using an HPGe detector,whereby Compton scattering background is suppressed and a low minimum detectable activity(MDA)is achieved without using an expensive and complex anticoincidence detector and *** electric-field-strength and energy-deposition distributions of the detector are simulated to determine the relationship between pulse shape and energy-deposition location,as well as the characteristics of energy-deposition distributions for fulland partial-energy deposition *** relationship is used to develop a pulse-shape-discrimination algorithm based on an artificial neural network for pulse-feature *** accurately determine the relationship between the deposited energy of gamma(γ)rays in the detector and the deposition location,we extract four shape parameters from the pulse signals output by the *** learning is used to input the four shape parameters into the ***,the pulse signals are identified and classified to discriminate between partial-and full-energy deposition *** partial-energy deposition events are removed to suppress Compton *** proposed method effectively decreases the MDA of an HPGeγ-energy dispersive *** results show that the Compton suppression factors for energy spectra obtained from measurements on ^(152)Eu,^(137)Cs,and ^(60)Co radioactive sources are 1.13(344 keV),1.11(662 keV),and 1.08(1332 keV),respectively,and that the corresponding MDAs are 1.4%,5.

关键词： High-purity germaniumγ-ray spectrometer Pulse-shape discrimination Compton scattering Artificial neural network Minimum detectable activity

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Desert ecological control and ecological industrial construction: Practice and inspiration from China

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China Geology 2024年第3期7卷 596-600页

作者： Xue-zheng Gao Lu Liu Yun-tao shang fan-yu Qi Development and Research Center China Geological SurveyMinistry of Natural ResourcesBeijing 100037China National Geological Archives of China Beijing 100037China China Construction Engineering Design&Research Institute Co. Ltd.Beijing 100037China

Desertification poses significant threats to the ecological security and sustainable economic and social development of countries worldwide. In China, existing desertified land primarily lies between 35°–50°N, covering arid and semi-arid regions and a total area of 1.688×106 km^(2), which represents 17.58%of the total territorial area of the country (Fig. 1).

关键词： Desert ecological primarily

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Superhydrophobic melamine sponge prepared by radiation-induced grafting technology for efficient oil-water separation

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Nuclear Science and Techniques 2024年第9期35卷 103-114页

作者： Ying Sun wen-Rui Wang Dan-Yi Li Si-Yi Xu Lin Lin Man-Li Lu Kai fan Chen-Yang Xing Lin-fan Li Ji-Hao Li shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China School of Architecture and Materials Chongqing College of Electronic EngineeringChongqing 401331China Center for Stretchable Electronics and NanoSensors Key Laboratory of Optoelectronic Devices and Systems of Ministry of EducationCollege of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen 518060China

This paper presents a superhydrophobic melamine(ME)sponge(ME-g-PLMA)prepared via high-energy radiation-induced in situ covalent grafting of long-alkyl-chain dodecyl methacrylate(LMA)onto an ME sponge for efficient oil–water *** obtained ME-g-PLMA sponge had an excellent pore structure with superhydrophobic(water contact angle of 154°)and superoleophilic *** can absorb various types of oils up to 66–168 times its *** ME-g-PLMA sponge can continuously separate oil slicks in water by connecting a pump or separating oil underwater with a gravity-driven *** addition,it maintained its highly hydrophobic properties even after long-term immersion in different corrosive solutions and repeated oil *** modified ME-g-PLMA sponge exhibited excellent separation properties and potential for oil spill cleanup.

关键词： Radiation-induced graft polymerization Oil–water separation Sponge Superhydrophobic

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Synergism of solar-driven interfacial evaporation and photo-Fenton Cr(Ⅵ) reduction by sustainable Bi-MOF-based evaporator from waste polyester

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Journal of Energy Chemistry 2024年第7期94卷 527-540页

作者： Zifen fan Jie Liu Huajian Liu Lijie Liu Yan She Xueying wen Huiyue Wang Guixin Hu Ran Niu Jiang Gong Key Laboratory of Material Chemistry for Energy Conversion and Storage Ministry of EducationHubei Key Laboratory of Material Chemistry and Service FailureHubei Engineering Research Center for Biomaterials and Medical Protective MaterialsSemiconductor Chemistry CenterSchool of Chemistry and Chemical EngineeringHuazhong University of Science andTechnologyWuhan430074HubeiChina

The integration of interfacial solar steam generation and photocatalytic degradation technology has pro-vided a promising platform to simultaneously produce freshwater and degrade ***,con-structing low-cost,multi-functional evaporators for treating Cr(Ⅵ)-polluted water remains challenging,and the synergistic mechanism on Cr(Ⅵ)reduction is ***,we propose the combined strategy of ball milling and solution mixing for the sustainable production of Bi-MOF microrod from waste poly(ethylene terephthalate),and construct Bi-MOF-based solar evaporators for simultaneous photo-Fenton Cr(Ⅵ)reduction and freshwater ***,the evaporator comprised of Bi-MOF microrod and graphene nanosheet possesses high light absorption,efficient photothermal conversion,and good hydro-philic *** to the advantages,the hybrid evaporator exhibits the evaporation rate of 2.16 kg m^(-2) h^(-1) and evaporation efficiency of 87.5%under 1 kW m^(-2) of *** integrating with photo-Fenton reaction,the Cr(Ⅵ)reduction efficiency is 91.3%,along with the reaction kinetics of 0.0548 min^(-1),surpassing many advanced *** the outdoor freshwater production and Cr(Ⅵ)reduction,the daily accumulative water yield is 5.17 kg m^(-2) h^(-1),and the Cr(Ⅵ)reduction efficiency is 99.9%.Furthermore,we prove that the localization effect derived from the interfacial solar-driven evap-oration enhances H_(2)O_(2) activation for the photo-Fenton reduction of Cr(Ⅵ).Based on the result of density functional theory,Bi-MOF microrod provides rich active centers for H_(2)O_(2) activation to produce active sites such as e-or-O_(2).This study not only proposes a new strategy to construct multi-functional solar evaporators for freshwater production and catalytic reduction of pollutants,but also advances the chem-ical upcycling of waste polyesters.

关键词： Interfacial solar steam generation Cr(VI)reduction Photo-Fenton reaction Metal-organic framework Waste plastic upcycling

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Spatial distribution characteristics and influence factor analysis of landslides——case study of the Hanwang area in Qinba Mountains

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Earthquake Research Advances 2024年第3期4卷 55-65页

作者： Jikai Zhang Yanbo Cao wen fan wenbo Zheng Zequan Wang Chengcheng He Hongquan Teng School of Geological Engineering and Geomatics Chang’an UniversityXi'an710054China Mine Geological Disasters Mechanism and Prevention Key Laboratory Xi'an710054China China DK Comprehensive Investigate and Design Research Institute Co. Ltd.Xi'an710054China Shaanxi Engineering Technology Research Center for Urban Geology and Underground Space Xi'an710068China Shaanxi Hydrogeology Engineering Geology and Environment Geology Survey CenterXi'an710068China Chang'an University Xi'anShaanxiChina

The geological hazards of landslides in Hanwang Town, Ziyang County, Ankang City, Shaanxi Province, have emerged. Yet, the current understanding of the spatial distribution characteristics and influencing factors of landslides in this area remains unclear. Combining the results of remote sensing interpretation and field investigation, seven influencing factors, namely, elevation, slope direction, slope gradient, distance from rivers, distance from faults, engineering geologic lithology, and distance from roads, are selected for the study. The distribution characteristics of landslides in each influencing factor and the influence of the resolution of the Digital Elevation Model(DEM) on the results are statistically and analytically analyzed. Furthermore, two highrisk landslides within the study area were subjected to comprehensive analysis, integrating the findings from drilling and other field investigations in order to examine their deformation mechanisms. Based on this analysis,the following conclusions were derived:(1) 34 landslides in the study area, mainly small earth landslides, with a distribution density of 0.42/km~2, threatening 414 people and property of about 55.87 million Yuan.(2)The landslides in the study area easily occur in the <400 m elevation range;the landslides are developed in all slope directions, the gradient is mainly concentrated in the range of 10°–40°, the distribution density of the landslides is higher in the closer distance from the river and the faults(0–200 m), the landslide-prone strata are mainly the softer and weaker metamorphic rocks, and the landslides are mainly around roads.(3) The resolution of the DEM should be selected based on the specific conditions of the study area, the requirements of the investigation, and the scale of the landslide. Opting for an appropriate DEM resolution is advantageous for understanding the patterns of landslides and conducting risk assessments in the region.(4) The Zhengjiabian landslide is a trac

关键词： Landslide Spatial distribution Influence factor Landslide density Deformation mechanism DEM

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Z-scheme Bi_(4)O_(5)Br_(2)/NH_(2)-MIL-125(Ti)heterojunctions enable exceptional visible photocatalytic degradation of organic pollutant

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Rare Metals 2024年第7期43卷 3161-3172页

作者： Feng Huang Muhammad Humayun Gang Li Ting-Ting fan wen-Lin Wang Yu-Lin Cao Anton Nikiforov Chun-Dong Wang Jing Wang Key Laboratory of Analytical Science and Technology of Hebei Province Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of EducationState Key Laboratory of New Pharmaceutical Preparations and ExcipientsCollege of Chemistry and Materials ScienceHebei UniversityBaoding071002China Energy Water and Environment LabCollege of Humanities and SciencesPrince Sultan University11586 RiyadhSaudi Arabia Baoding Green Yijia Environmental Protection Technology Ltd Baoding 071051China Physics Laboratory Industrial Training CenterShenzhen Polytechnic UniversityShenzhen 518055China Department of Applied Physics Ghent University9000 GhentBelgium School of Integrated Circuits Wuhan National Laboratory for OptoelectronicsHuazhong University of Science and TechnologyWuhan 430074China

One key strategy to enhance photocatalytic performance is to improve the transfer and separation efficiency of photogenerated carriers by building optimized ***,novel Bi_(4)O_5Br_(2)/NH_(2)-MIL-125(Ti)Z-scheme heterojunctions are fabricated and used as photocatalysts for organic pollutant *** NH_(2)-MIL-125(Ti)nanosheets are exfoliated via a self-developed alkali solution stripping approach and then uniformly decorated on Bi_(4)O_(5)Br_(2).The as-prepared Bi_(4)O_(5)Br_(2)/NH_(2)-MIL-125(Ti)presents more than 90%degradation of various pollutants,outperforming the counterpart individual *** various characterization results suggest that the enhanced degradation rate is due to the more intimate face-to-face interfacial contact of the lamellar Z-scheme heterojunction materials,in which the migration path of carriers from the material's interior to the surface can be reduced,in turn enhancing migration efficiency and separation capability significantly.A possible photocatalytic reaction mechanism is proposed based on the photoelectric behaviors,radical trapping experiments and liquid chromatography mass spectrometry *** work promotes the development of new photocatalytic materials for heterojunctions with face-to-face interfacial contacts,as well as the effective purification of wastewater in environmental remediation.

关键词： Z-scheme heterojunctions Photocatalysis Alkaline solution stripping Bi_(4)O_(5)Br_(2) NH_(2)-MIL-125(Ti)

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Study on the clogging mechanism of punching screen in sand control by the punching structure parameters

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Petroleum Science 2024年第1期21卷 609-620页

作者： Fu-Cheng Deng Fu-Lin Gui Bai-Tao fan Lei wen Sheng-Hong Chen Ning Gong Yun-Chen Xiao Zhi-Hui Xu Yangtze University Jingzhou434023HubeiChina CNOOC Research Institute Ltd. Beijing100028China CNOOC Ener Tech-Drilling&Production Co. Tianjin300457China Tianjin Branch of CNOOC Ltd. Tianjin300459China

As an independent sand control unit or a common protective shell of a high-quality screen,the punching screen is the outermost sand retaining unit of the sand control pipe which is used in geothermal well or oil and gas ***,most screens only consider the influence of the internal sand retaining medium parameters in the sand control performance design while ignoring the influence of the plugging of the punching screen on the overall sand retaining performance of the *** explore the clogging mechanism of the punching screen,this paper established the clogging mechanism calculation model of a single punching screen sand control unit by using the computational fluid mechanics-discrete element method(CFD-DEM)combined *** to the combined motion of particles and fluids,the influence of the internal flow state on particle motion and accumulation was *** results showed that(1)the clogging process of the punching sand control unit is divided into three stages:initial clogging,aggravation of clogging and stability of *** the initial stage of blockage,coarse particles form a loose bridge structure,and blockage often occurs preferentially at the streamline gathering place below chamfering inside the sand control *** the stage of blockage intensification,the particle mass develops into a relatively complete sand bridge,which develops from both ends of the opening to the center of the *** the stable plugging stage,the sand deposits show a“fan shape”and form a“V-shaped”gully inside the punching slot element.(2)Under a certain reservoir particle-size distribution,The slit length and opening height have a large influence on the permeability and blockage rate,while the slit width size has little influence on the permeability and blockage *** microscopic clogging mechanism and its law of the punching screen prevention unit are proposed in this study,which has some field guidance significance for the design of punching screen

关键词： Punching screen Plugging CFD-DEM Size parameter Sand control

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Laser-rewritable room temperature phosphorescence based on in-situ polymerized tartaric acid

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Science China Chemistry 2024年第9期67卷 3029-3038页

作者： Tuo-Yu Zhou Tai-wen Li Hai-Fu Zhang Rui-Lin Chai Qian Zhao Penglin Zhang Guang-Yue Li Qian-wen Wang Chang Li Yu Shu Zhi fan Sheng-Hua Li College of Chemical Engineering and Materials Science College of SciencesTianjin University of Science&TechnologyTianjin 300457China College of Chemical Engineering North China University of Science and TechnologyTangshan 063210China Tianjin Key Laboratory of Multiplexed Identification for Port Hazardous Chemicals Tianjin University of Science&TechnologyTianjin 300457China

Organic room temperature phosphorescence(RTP)materials have potential applications in information technology and ***,the precise control of the afterglow in reversible manners remains challenging for organic ***,we report a kind of organic RTP material fabricated by simple heating mixtures of tartaric acid(TA)and aromatic acids,which can switch their phosphorescence by *** mixtures show tunable phosphorescence from indigo to orange with phosphorescence efficiency of up to 53.99% due to locking different organic luminogens by the TA-formed matrix through the noncovalent *** afterglow of those materials lasts a few seconds and disappears by water fumigation,which can be repeated in response to wet/heat *** drop-casting those materials on glass slides,a laser-repatternable phosphorescence is achieved by facile laser direct writing and quenched by water *** results open the opportunity for the design of smart stimuli-responsive phosphorescence materials from sustainable natural products.

关键词： room temperature phosphorescence tunable afterglows tartaric acid laser direct writing stimuli-response

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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

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Method for the real-time detection of tomato ripeness using a phenotype robot and RP-YolactEdge

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International Journal of Agricultural and Biological Engineering 2024年第2期17卷 200-210页

作者： Yuanqiao Wang wenbo Gou Chuanyu Wang Jiangchuan fan Weiliang wen Xianju Lu Xinyu Guo Chunjiang Zhao College of Information Engineering Northwest A&F UniversityYangling 712100ShaanxiChina China National Engineering Research Center for Information Technology in Agriculture(NERCITA) Beijing 100097China Beijing Key Laboratory of Digital Plant Beijing Research Center for Information Technology in AgricultureBeijing 100097China Beijing PAIDE Science and Technology Development Co. Ltd.Beijing 100097China

In order to address the challenge of non-destructive detection of tomato fruit ripeness in controlled environments,this study proposed a real-time instance segmentation method based on the edge *** method combined the principles of phenotype robots and machine vision based on deep learning.A compact and remotely controllable phenotype detection robot was employed to acquire precise data on tomato *** video data were then processed by using an efficient backbone and the FeatFlowNet structure for feature extraction and analysis of key-frame to non-key-frame mapping from video *** enhance the diversity of training datasets and the generalization of the model,an innovative approach was chosen by using random enhancement ***,the PolyLoss optimization technique was applied to further improve the accuracy of the ripeness multi-class detection *** validation,the method of this study achieved real-time processing speeds of 90.1 fps(RTX 3070Ti)and 65.5 fps(RTX 2060 S),with an average detection accuracy of 97%compared to manually measured *** is more accurate and efficient than other instance segmentation models according to actual testing in a ***,the results of this research can be deployed in edge devices and provide technical support for unmanned greenhouse monitoring devices or fruit-picking robots in facility environments.

关键词： instance segmentation phenotype robot tomato greenhouse-based plant phenotyping ripeness detection

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