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Fine Sand and Clay Sediment Acoustic Properties of the Novel Sediment Sample from the Arabian Sea:Experimental Investigations and Biot−Stoll Model Validation

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China Ocean Engineering 2024年第1期38卷 169-180页

作者： Shahabuddin SHAIKH HUANG Yi-wang ZHANG Ze-chuan Habib Hussain ZUBERI National key laboratory of Underwater Acoustic Technology and College of Underwater Acoustic Engineering Harbin Engineering UniversityHarbin 150001China

The present study explores the physical and acoustic characteristics of fine sand and clay in novel seabed marine sediments from of Pakistan coastline of the Arabian *** measured physical parameters included mean grain size,mass density,bulk density,salinity,porosity,permeability,pore size and mineralogical *** properties,including sound speed and attenuation,in the high frequency range of 90-170 kHz were analyzed.A controlled laboratory setup with the acoustic transmission method and Fourier transform techniques was utilized to examine the sound propagation and absorption of novel seabed *** standard deviation of mean sound speed in fresh water was 0.75 m/s,and attenuation was observed in the range of 0.43 to 0.61 dB/*** mean sound velocity in sand and clay varied from 1706 to 1709 m/s and 1602 to 1608 m/s,*** average attenuation was observed at 80 to 93 dB/m in sandy sediments and from 31.8 to 38.6 dB/m in clayey *** velocity variation within sandy sediment is low,consistent with expected results,and smaller than the predicted ***,clay sediment exhibited a positive linear correlation and low sound speed *** increased linearly with frequency for both ***,the laboratory results were validated by using the Biot−Stoll *** dispersion of sound speed in sandy and clayey sediments was consistent with the predictions of the Biot−Stoll *** attenuation aligned more with Biot−Stoll model predictions due to improved permeability,tortuosity and pore size parameter fitting.

关键词： physical and acoustic characteristics marine sediments sound speed attenuation Biot−Stoll model

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Recent progress on nanomaterial-based electrochemical dissolved oxygen sensors

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Chinese Journal of Chemical Engineering 2024年第4期68卷 103-119页

作者： Shaoqi Zhang Tao Liu Zhenyu Chu Wanqin Jin State key laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringNanjing Tech UniversityNanjing 211816China

Dissolved oxygen(DO)usually refers to the amount of oxygen dissolved in *** the environment,medicine,and fermentation industries,the DO level needs to be accurate and capable of online monitoring to guide the precise control of water quality,clinical treatment,and microbial *** with other analytical methods,the electrochemical strategy is superior in its fast response,low cost,high sensitivity,and portable ***,an electrochemical DO sensor faces a trade-off between sensitivity and long-term stability,which strongly limits its practical *** solve this problem,various advanced nanomaterials have been proposed to promote detection performance owing to their excellent electrocatalysis,conductivity,and chemical ***,in this review,we focus on the recent progress of advanced nanomaterial-based electrochemical DO *** the comparison of the working principles on the main analysis techniques toward DO,the advantages of the electrochemical method are *** is placed on recently developed nanomaterials that exhibit special characteristics,including nanostructures and preparation routes,to benefit DO ***,we also introduce some interesting research on the configuration design of the electrode and device,which is rarely ***,the different requirements of the electrochemical DO sensors in different application fields are included to provide brief guidance on the selection of appropriate ***,the main challenges are evaluated to propose future development prospects and detection strategies for nanomaterial-based electrochemical sensors.

关键词： Nanomaterial Dissolved oxygen Electrochemical sensor Nanostructures Detection principles

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A benchmark-based method for evaluating hyperparameter optimization techniques of neural networks for surface water quality prediction

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Frontiers of Environmental Science & Engineering 2024年第5期18卷 13-27页

作者： Xuan Wang Yan Dong Jing Yang Zhipeng Liu Jinsuo Lu School of Environmental and Municipal Engineering Xi’an University of Architecture and TechnologyXi’an710055China Shaanxi key laboratory of Environmental Engineering Xi’an University of Architecture and TechnologyXi’an710055China State key laboratory of Green Building in West China Xi’an University of Architecture and TechnologyXi’an710055China

Neural networks(NNs)have been used extensively in surface water prediction tasks due to computing algorithm improvements and data *** essential step in developing an NN is the hyperparameter *** practice,it is common to manually determine hyperparameters in the studies of NNs in water resources *** may result in considerable randomness and require significant computation time;therefore,hyperparameter optimization(HPO)is *** study adopted five representatives of the HPO techniques in the surface water quality prediction tasks,including the grid sampling(GS),random search(RS),genetic algorithm(GA),Bayesian optimization(BO)based on the Gaussian process(GP),and the tree Parzen estimator(TPE).For the evaluation of these techniques,this study proposed a method:first,the optimal hyperparameter value sets achieved by GS were regarded as the benchmark;then,the other HPO techniques were evaluated and compared with the benchmark in convergence,optimization orientation,and consistency of the optimized *** results indicated that the TPE-based BO algorithm was recommended because it yielded stable convergence,reasonable optimization orientation,and the highest consistency rates with the benchmark *** optimization consistency rates via TPE for the hyperparameters hidden layers,hidden dimension,learning rate,and batch size were 86.7%,73.3%,73.3%,and 80.0%,*** the evaluation of HPO techniques directly based on the prediction performance of the optimized NN in a single HPO test,the proposed benchmark-based HPO evaluation approach is feasible and robust.

关键词： Neural networks Hyperparameter optimization Surface water quality prediction Bayes optimization Genetic algorithm

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Highly Improved Creep Resistance in Polypropylene Through Thermally Reduced Graphene Oxide and Its Creep Lifetime Prediction

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Chinese Journal of Polymer Science 2024年第2期42卷 256-266,I0010页

作者： Can-Can Zhang Jun-Long Yang Ya-Jiang Huang Guang-Xian Li College of Polymer Science and Engineering State Key Laboratory of Polymer Materials Engineering of ChinaSichuan UniversityChengdu610065China

Polypropylene(PP) exhibits suboptimal creep resistance due to the presence of methyl groups on its main chain, leading to irregular chain segment distribution, diminished inter-chain interaction, and crystallinity. This structural feature causes chain slippage in PP under stress,significantly constraining its service lifetime. In this study, thermally reduced graphene oxide(TrGO) nanosheets were incorporated into the PP matrix, yielding a nanocomposite with exceptional creep resistance performance. Results demonstrated that at a stress of 25 MPa, a 2.0 wt% TrGO content could enhance the creep failure lifetime of PP by 21.5 times compared to neat PP. Rheology, transmission electron microscopy(TEM),and scanning electron microscopy(SEM) characterization techniques were employed to analyze the mechanism of TrGO's influence on PP's creep behavior. It was observed that when TrGO content exceeded 1.0 wt%, an effective particle network structure formed within the PP matrix. This homogeneously dispersed TrGO-formed particle network structure restricted the migration and rearrangement of PP molecular chains, enabling prolonged stress resistance without structural failure. By combining the time-strain superposition method with the critical failure strain as a criterion, generalized creep compliance curves for PP and its composites were established, facilitating the prediction of material creep failure lifetimes, with a strong agreement between experimental and predicted lifetime values. This research proposes a novel strategy aimed at developing polypropylene materials and products with enhanced long-term stability and durability, thus extending service life, reducing failure risk, and broadening their potential across various application domains.

关键词： Thermally reduced graphene oxide Polypropylene Creep failure and lifetime prediction

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A unique subseafloor microbiosphere in the Mariana Trench driven by episodic sedimentation

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Marine Life Science & Technology 2024年第1期6卷 168-181页

作者： Jiwen Liu Da-Wei Li Xinxin He Ronghua Liu Haojin Cheng Chenglong Su Mengna Chen Yonghong Wang Zhongsheng Zhao Hanyue Xu Zhangyu Cheng Zicheng Wang Nikolai Pedentchouk David J.Lea-Smith Jonathan D.Todd Xiaoshou Liu Meixun Zhao Xiao-Hua Zhang Frontiers Science Center for Deep Ocean Multispheres and Earth System and College of Marine Life SciencesOcean University of ChinaQingdao 266003China laboratory for Marine Ecology and Environmental Science Laoshan LaboratoryQingdao 266237China Institute of Evolution and Marine Biodiversity Ocean University of ChinaQingdao 266003China key laboratory of Marine Chemistry Theory and Technology Ministry of EducationOcean University of ChinaQingdao 266100China key Lab of Submarine Geosciences and Prospecting techniques Ministry of Education/College of Marine GeosciencesOcean University of ChinaQingdao 266100China key laboratory of Physical Oceanography Ministry of Education/Research Vessel CentreOcean University of ChinaQingdao 266100China School of Environmental Sciences University of East AngliaNorwich NR47TJUK School of Biological Sciences University of East AngliaNorwich NR47TJUK

Hadal trenches are characterized by enhanced and infrequent high-rate episodic sedimentation events that likely introduce not only labile organic carbon and key nutrients but also new microbes that significantly alter the subseafloor ***,the role of high-rate episodic sedimentation in controlling the composition of the hadal subseafloor microbiosphere is ***,analyses of carbon isotope composition in a~750 cm long sediment core from the Challenger Deep revealed noncontinuous deposition,with anomalous ^(14)C ages likely caused by seismically driven mass transport and the funneling effect of trench *** community composition and diverse enzyme activities in the upper~27 cm differed from those at lower depths,probably due to sudden sediment deposition and differences in redox condition and organic matter *** lower depths,microbial population numbers,and composition remained relatively constant,except at some discrete depths with altered enzyme activity and microbial phyla abundance,possibly due to additional sudden sedimentation events of different *** is provided of a unique role for high-rate episodic sedimentation events in controlling the subsurface microbiosphere in Earth’s deepest ocean floor and highlight the need to perform thorough analysis over a large depth range to characterize hadal benthic *** depositional processes are likely crucial in shaping deep-water geochemical environments and thereby the deep subseafloor biosphere.

关键词： Hadal subseafloor Deep water sediment Mariana Trench Radiocarbon Microbial community Redox potential

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Analyzing the surface passivity effect of germanium oxynitride:a comprehensive approach through first principles simulation and interface state density

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Nuclear Science and techniques 2024年第5期35卷 74-84页

作者： Sheng-Jie Du Xiu-Xia Li Yang Tian Yuan-Yuan Liu Ke Jia Zhong-Zheng Tang Jian-Ping Cheng Zhi Deng Yu-Lan Li Zheng-Cao Li Sha-Sha Lv College of Nuclear Science and Technology Joint laboratory of Jinping Ultra‑Low Radiation Background Measurement of Ministry of Ecology and Environment key laboratory of Beam Technology of Ministry of Education Beijing Normal UniversityBeijing Normal UniversityBeijing 100875China Joint Research Center Nuctech Company LimitedBeijing 100084China Department of Engineering Physics Key Laboratory of Particle&Radiation Imaging of Ministry of EducationTsinghua UniversityBeijing 100084China key laboratory of Advanced Materials(MOE) School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

High-purity germanium(HPGe)detectors,which are used for direct dark matter detection,have the advantages of a low threshold and excellent energy *** surface passivation of HPGe has become crucial for achieving an extremely low energy *** this study,first-principles simulations,passivation film preparation,and metal oxide semiconductor(MOS)capacitor characterization were combined to study surface *** calculations of the energy band structure of the -H,-OH,and -NH_(2) passivation groups on the surface of Ge were performed,and the interface state density and potential with five different passivation groups with N/O atomic ratios were accurately analyzed to obtain a stable surface *** on the theoretical calculation results,the surface passivation layers of the Ge_(2)ON_(2) film were prepared via magnetron sputtering in accordance with the optimum atomic ratio *** microstructure,C-V,and I-V electrical properties of the layers,and the passivation effect of the Al/Ge_(2)ON_(2)/Ge MOS were characterized to test the interface state *** mean interface state density obtained by the Terman method was 8.4×10^(11) cm^(-2) eV^(-1).The processing of germanium oxynitrogen passivation films is expected to be used in direct dark matter detection of the HPGe detector surface passivation technology to reduce the detector leakage currents.

关键词： Surface passivation High purity germanium detector Germanium nitrogen oxide Interface state density

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Application of machine learning in perovskite materials and devices:A review

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Journal of Energy Chemistry 2024年第7期94卷 254-272页

作者： Ming Chen Zhenhua Yin Zhicheng Shan Xiaokai Zheng Lei Liu Zhonghua Dai Jun Zhang Shengzhong(Frank)Liu Zhuo Xu School of Electric Power Civil Engineering and ArchitectureCollege of Physics and Electronics EngineeringState Key Laboratory of Quantum Optics and Quantum Optics DevicesShanxiUniversityTaiyuan030006ShanxiChina key laboratory of Applied Surface and Colloid Chemistry National Ministry of EducationShanxi Engineering Lab for Advanced Energy TechnologySchool of Materials Science and EngineeringShaanxi Normal UniversityXi'an 710119ShaanxiChina State key laboratory of Catalysis Dalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina

Metal-halide hybrid perovskite materials are excellent candidates for solar cells and photoelectric *** recent years,machine learning(ML)techniques have developed rapidly in many fields and provided ideas for material discovery and *** can be applied to discover new materials quickly and effectively,with significant savings in resources and time compared with traditional experiments and density functional theory(DFT)*** this review,we present the application of ML in per-ovskites and briefly review the recent works in the field of ML-assisted perovskite ***,the advantages of perovskites in solar cells and the merits of ML applied to perovskites are ***,the workflow of ML in perovskite design and some basic ML algorithms are ***,the applications of ML in predicting various properties of perovskite materials and devices are ***,we propose some prospects for the future development of this *** rapid devel-opment of ML technology will largely promote the process of materials science,and ML will become an increasingly popular method for predicting the target properties of materials and devices.

关键词： Machine learning Perovskite Materials design Bandgap engineering Stability Crystal structure

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Gapless Genome Assembly of ZH8015 and Preliminary Multi-Omics Analysis to Investigate ZH8015's Responses Against Brown Planthopper Infestation

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Rice science 2024年第3期31卷 317-327,I0042-I0045页

作者： LI Dian DUAN Wenjing LIU Qun’en WU Weixun ZHAN Xiaodeng SUN Lianping ZHANG Yingxin CHENG Shihua State key laboratory of Rice Biology and Breeding China National Rice Research InstituteHangzhou 310006China

Accurate genomic information is essential for advancing genetic breeding research in specific rice *** study presented a gapless genome assembly of the indica rice cultivar Zhonghui 8015(ZH8015)using Pac Bio HiFi,Hi-C,and ONT(Oxford Nanopore Technologies)ultra-long sequencing technologies,annotating 43037 gene ***,utilizing this genome along with transcriptomic and metabolomic techniques,we explored ZH8015's response to brown planthopper(BPH)*** transcriptomic sampling indicated significant changes in gene expression levels around 48 h after BPH *** analysis revealed particularly significant alterations in genes related to reactive oxygen species scavenging and cell wall *** results demonstrated marked increases in levels of several monosaccharides,which are components of the cell wall and dramatic changes in flavonoid *** association analysis identified differentially expressed genes associated with key metabolites,shedding light on ZH8015's response to BPH *** summary,this study constructed a reliable genome sequence resource for ZH8015,and the preliminary multi-omics results will guide future insect-resistant breeding research.

关键词： brown planthopper gapless genome genome assembly multi-omics Nilaparvata lugens rice

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The medium-temperature dependence of jet transport coefficient in high-energy nucleus-nucleus collisions

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Nuclear Science and techniques 2024年第7期35卷 173-191页

作者： Man Xie Qing-Fei Han En-Ke Wang Ben-Wei Zhang Han-Zhong Zhang key laboratory of Atomic and Subatomic Structure and Quantum Control(MOE) Guangdong Basic Research Center of Excellence for Structure and Fundamental Interactions of MatterInstitute of Quantum Matter South China Normal UniversityGuangzhou510006China Guangdong-Hong Kong Joint laboratory of Quantum Matter Guangdong Provincial Key Laboratory of Nuclear ScienceSouthern Nuclear Science Computing CenterSouth China Normal UniversityGuangzhou 510006China key laboratory of Quark and Lepton Physics(MOE)and Institute of Particle Physics Central China Normal UniversityWuhan430079China

The medium-temperature T dependence of the jet transport coefficient̂q was studied via the nuclear modification factor RAA(p_(T))and elliptical flow parameter v_(2)(p_(T))for large transverse momentum p_(T) hadrons in high-energy nucleus-nucleus *** a next-to-leading-order perturbative QCD parton model for hard scatterings with modified fragmentation functions due to jet quenching controlled by q,we check the suppression and azimuthal anisotropy for large p_(T) hadrons,and extract q by global fits to RAA(pT)and v_(2)(pT)data in A+A collisions at RHIC and LHC,*** numerical results from the best fits show that q∕T^(3) goes down with local medium-temperature T in the parton jet *** with the case of a constant q∕T^(3),the going-down T dependence of q∕T^(3) makes a hard parton jet to lose more energy near T_(c) and therefore strengthens the azimuthal anisotropy for large pT *** a result,v_(2)(p_(T))for large pT hadrons was enhanced by approximately 10%to better fit the data at RHIC/*** the first-order phase transition from QGP to the hadron phase and the additional energy loss in the hadron phase,v_(2)(p_(T))is again enhanced by 5-10%at RHIC/LHC.

关键词： Jet quenching Jet transport parameter Hadron suppression Elliptic flow coefficient Energy loss asymmetry

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Control of interfacial reaction and defect formation in Gd/Bi_(2)Te_(2.7)Se_(0.3) composites with excellent thermoelectric and magnetocaloric properties

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Chinese Physics B 2024年第8期33卷 474-481页

作者：薛天畅魏平刘承姗李龙舟朱婉婷聂晓蕾赵文俞 State key laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China

The method to combine thermoelectric(TE)and magnetocaloric(MC)cooling techniques lies in developing a new material that simultaneously possesses a large TE and good MC cooling *** this work,using n-type Bi_(2)Te_(2.7)Se_(0.3)(BTS)as the TE base material and Gd as the second-phase MC material,Gd/BTS composites were prepared by the spark plasma sintering *** the composites,interfacial reaction between Gd and BTS was identified,resulting in the formation of Gd Te,which has a large impact on the electron concentration through the adjustment of defect *** MC/TE composite containing 2.5 wt%Gd exhibited a ZT value of 0.6 at 300 K,essentially retaining the original TE performance,while all the composites largely maintained the excellent MC performance of *** work provides a potential pathway to achieving high performance in MC/TE composites.

关键词： thermo-electro-magnetic energy conversion materials interfacial reaction thermoelectric performance magnetic entropy change

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