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Incorporation of source contributions to improve the accuracy of soil heavy metal mapping using small sample sizes at a county scale

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Pedosphere 2024年第1期34卷 170-180页

作者： jie SONG Xin wang Dongsheng YU Jiangang LI Yanhe ZHAO Siwei wang Lixia MA State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China Chinese Academy of Sciences University Beijing 100049China Agricultural and Rural Bureau of Luanping County Luanping 068250China

Estimating heavy metal(HM) distribution with high precision is the key to effectively preventing Chinese medicinal plants from being polluted by the native soil. A total of 44 surface soil samples were gathered to detect the concentrations of eight HMs(As, Hg, Cu, Cr, Ni, Zn, Pb, and Cd) in the herb growing area of Luanping County, northeastern Hebei Province, China. An absolute principal component score-multiple linear regression(APCS-MLR) model was used to quantify pollution source contributions to soil HMs. Furthermore, the source contribution rates and environmental data of each sampling point were simultaneously incorporated into a stepwise linear regression model to identify the crucial indicators for predicting soil HM spatial distributions. Results showed that 88% of Cu, 72% of Cr, and 72% of Ni came from natural sources;50% of Zn, 49% of Pb, and 59% of Cd were mainly caused by agricultural activities;and 44% of As and 56% of Hg originated from industrial activities. When three-type(natural, agricultural, and industrial) source contribution rates and environmental data were simultaneously incorporated into the stepwise linear regression model, the fitting accuracy was significantly improved and the model could explain 31%–86% of the total variance in soil HM concentrations. This study introduced three-type source contributions of each sampling point based on APCS-MLR analysis as new covariates to improve soil HM estimation precision, thus providing a new approach for predicting the spatial distribution of HMs using small sample sizes at the county scale.

关键词： absolute principal component score-multiple linear regression Chinese herbal medicine influencing factors spatial distribution stepwise multiple regression

Mapping soil organic matter in cultivated land based on multi-year composite images on monthly time scales

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Journal of Integrative Agriculture 2024年第4期23卷 1393-1408页

作者： jie Song Dongsheng Yu Siwei wang Yanhe Zhao Xin wang Lixia Ma Jiangang Li State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China Agricultural and Rural Bureau of Luanping County Luanping 068250China Chinese Academy of Sciences University Beijing 100049China

Rapid and accurate acquisition of soil organic matter(SOM)information in cultivated land is important for sustainable agricultural development and carbon balance *** study proposed a novel approach to predict SOM with high accuracy using multiyear synthetic remote sensing variables on a monthly *** obtained 12 monthly synthetic Sentinel-2 images covering the study area from 2016 to 2021 through the Google Earth Engine(GEE)platform,and reflectance bands and vegetation indices were extracted from these composite *** the random forest(RF),support vector machine(SVM)and gradient boosting regression tree(GBRT)models were tested to investigate the difference in SOM prediction accuracy under different combinations of monthly synthetic *** showed that firstly,all monthly synthetic spectral bands of Sentinel-2 showed a significant correlation with SOM(Paining bands did not exhibit significant *** research offers a new attempt to map SOM with high accuracy and fine spatial resolution based on monthly synthetic Sentinel-2 images.

关键词： soil organic matter Sentinel-2 monthly synthetic images machine learning model spatial prediction

A multiple flame-retardant,early fire-warning,and highly sensitive thread-shaped all-fabric-based piezoresistive sensor

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Science China(Technological Sciences) 2024年第4期67卷 1151-1159页

作者： LI WeiBiao ZHANG Shuai MA ShuQi wang JiaCheng wang Huan YANG QiRong SONG YongTao ZHU jie North China Institute of Aerospace Engineering Langfang 065000China Langfang Fire and Rescue Division of Hebei Province Langfang 065000China School of Information Science and Engineering Xinjiang College of Science and TechnologyKorla 841000China

In the artificial intelligence age,multifunctional and intelligent fireproof fabric-based electronics are urgently ***,a novel thread-shaped all-fabric-based piezoresistive sensor(denoted as TAFPS)with properties such as flame retardancy,firewarning,and piezoresistivity is proposed,which is composed of an inner nickel-plated fabric electrode,a multifunctional double helix fabric,and an external flame-retardant encapsulation *** to the multiple flame-retardant properties of glass fiber tubular fabric,aminated carbon nanotubes(ACNTs),and ammonium polyphosphate,the char residue of the TAFPS reaches40.3 wt%at 800℃.In addition,the heat-sensitive effect of ACNTs during combustion causes a rapid decrease in the TAFPS resistance,triggering the fire alarm system within 2 ***,benefiting from the force-sensitive behavior of the double helix layer and tightly wrapped pattern of the external heat-shrinkable tubular fabric,TAFPS demonstrated a high sensitivity of4.40 kPa^(-1)(0–5.81 k Pa)and good stability for 10000 *** its excellent flame resistance,high sensitivity,and agreeable stability,the developed TAFPS can be integrated into fire suits to monitor the exercise training process and the external fire *** work offers a novel approach for fabricating all-fabric-based piezoresistive sensors in the future for fire prevention and fire alarms,with promising applications in fire protection,the Internet of Things,and smart apparel.

关键词： all-fabric piezoresistive sensor multiple flame retardancy agile fire-warning high sensitivity

A novel mullite anti-gyroid/SiC gyroid ceramic metastructure based on digital light processing 3D printing with enhanced electromagnetic wave absorption and mechanical properties

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Journal of Advanced Ceramics 2024年第8期13卷 1212-1222页

作者： Chaoyang wang Xiao Chen Zhicheng wang Jjalin Bai jie Tang Yulong She Zhengren Huang Yong Yang State Key Laboratory of High Performance Ceramics and Superfine Microstructures Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China College of Materials Science and Opto-Electronic Technology University of Chinese Academy of SciencesBeijing 100049China

Sic-based composites are widely used as electromagnetic wave absorbers due to their excellent dielectric ***,the constraints associated with structural design and the intricacies of the preparation process hinder their broader *** this study,novel mullite anti-gyroid/SiC gyroid metastructures are designed to integrate the mechanical and electromagnetic wave(EMW)absorption properties of composite *** anti-gyroid/SiC gyroid composites are fabricated utilizing a combination of digital light processing(DLP)three-dimensional(3D)printing and precursor infiltration and pyrolysis(PiP)*** the modulation of structural units,the electromagnetic parameters can be effectively regulated,thus improving the impedance matching characteristics of the *** structural composites show outstanding EMW absorption properties,with a minimum reflection loss of-54 dB at a thickness of 1.9 mm and an effective absorption bandwidth of 3.20 GHz at a thickness of 2.2 ***,the PIP process significantly enhances the mechanical properties of the composites;compared with those of the mullite/SiC ceramics,the flexural strength of the composites is improved by 3.69-5.85 times(13.28±1.15 MPa vs.(49.05±1.07)-(77.78±3.72)MPa),and the compressive strength is improved by 4.59-13.58 times(8.55±0.90 MPa vs.(39.02±1.63)-(116.13±2.58)MPa).This approach offers a novel and effective method for fabricating structural composites with an expanded range of higher electromagnetic wave absorption properties and improved mechanical properties.

关键词： mullite anti-gyroid/SiC gyroid metastructures digital light processing(DLP) precursor infiltration and pyrolysis(PIP) electromagnetic waveabsorption

Contemporary strategies and approaches for characterizing composition and enhancing biofilm penetration targeting bacterial extracellular polymeric substances

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Journal of Pharmaceutical Analysis 2024年第4期14卷 506-524页

作者： Lan Lu Yuting Zhao Mingxing Li Xiaobo wang jie Zhu Li Liao Jingya wang Key Laboratory of Medicinal and Edible Plants Resources Development of Sichuan Education Department Sichuan Industrial Institute of AntibioticsSchool of PharmacyChengdu UniversityChengdu610000China Meishan Pharmaceutical Vocational College School of PharmacyMeishanSichuan620200China Laboratory of Molecular Pharmacology Department of PharmacologySchool of PharmacySouthwest Medical UniversityLuzhouSichuan646000China Hepatobiliary Surgery Langzhong People's HospitalLangzhongSichuan646000China

Extracellular polymeric substances(EPS)constitutes crucial elements within bacterial biofilms,facili-tating accelerated antimicrobial resistance and conferring defense against the host's immune *** precise and effective antibiofilm approaches and strategies,tailored to the specific charac-teristics of EPS composition,can offer valuable insights for the creation of novel antimicrobial ***,in turn,holds the potential to mitigate the alarming issue of bacterial drug *** analysis of EPS compositions relies heavily on colorimetric approaches with a significant bias,which is likely due to the selection of a standard compound and the cross-interference of various EPS *** the pivotal role of EPS in biofilm functionality,it is imperative for EPS research to delve deeper into the analysis of intricate compositions,moving beyond the current focus on polymeric *** ne-cessitates a shift from heavy reliance on colorimetric analytic methods to more comprehensive and nuanced analytical *** this study,we have provided a comprehensive summary of existing analytical methods utilized in the characterization of EPS ***,novel strategies aimed at targeting EPS to enhance biofilm penetration were explored,with a specific focus on high-lighting the limitations associated with colorimetric ***,we have outlined the challenges faced in identifying additional components of EPS and propose a prospective research plan to address these *** review has the potential to guide future researchers in the search for novel compounds capable of suppressing EPS,thereby inhibiting biofilm *** insight opens up a new avenue for exploration within this research domain.

关键词： Analytic strategies and approaches Composition characterization Extracellular polymeric substances(EPS) Promoting biofilm penetration

Ultrafast Molecular Movies:Probing Chemical Dynamics with Femtosecond Electron and X-Ray Diffraction

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CCS Chemistry 2024年第5期6卷 1092-1109页

作者： Qianci wang Longteng Yun jie Yang Center of Basic Molecular Science Department of ChemistryTsinghua UniversityBeijing 100084

Understanding the process of chemical reactions has always been a relentless pursuit for *** development of femtosecond pump-probe techniques since the 1980s has revolutionized the field of chemical dynamics,enabling the capture of timeresolved snapshots of reactions on the femtosecond *** from the 2010s,breakthroughs in femtosecond electron and X-ray sources has enabled ultrafast electron and X-ray diffraction techniques,which is able to directly reveal the temporal evolution of atomic geometries of molecules,allowing for the creation of molecular ***-phase molecular movies reveal intrinsic intramolecular processes,while liquid-phase molecular movies provide insights for complicated solvent-solute *** minireview focuses on the advances in studying gasphase and liquid-phase molecular dynamics(MD)using ultrafast electron and X-ray diffraction techniques on femtosecond and picosecond *** fast-developing experimental capability of the direct observation of molecular structural evolution during chemical reactions,on its natural femtosecond timescale and subangstrom length scale,offers tremendous potential for the field of chemical kinetics and MD.

关键词： molecular movie electron diffraction X-raydiffraction femtosecond gasphase liquidphase

Quantitative prediction model for the depth limit of oil accumulation in the deep carbonate rocks:A case study of Lower Ordovician in Tazhong area of Tarim Basin

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Petroleum Science 2024年第1期21卷 115-124页

作者： Wen-Yang wang Xiong-Qi Pang Ya-Ping wang Zhang-Xin Chen Fu-jie Jiang Ying Chen State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China College of Geosciences China University of Petroleum(Beijing)Beijing102249China Research Institute of Exploration and Development PetroChina Southwest Oil&Gas Field CompanyChengdu610041SichuanChina Chemical and Petroleum Engineering Schulich School of EngineeringUniversity of CalgaryCalgaryT2N 1N4Canada

With continuous hydrocarbon exploration extending to deeper basins,the deepest industrial oil accumulation was discovered below 8,200 m,revealing a new exploration ***,the extent to which oil exploration can be extended,and the prediction of the depth limit of oil accumulation(DLOA),are issues that have attracted significant attention in petroleum *** it is difficult to characterize the evolution of the physical properties of the marine carbonate reservoir with burial depth,and the deepest drilling still cannot reach the ***,the DLOA cannot be predicted by directly establishing the relationship between the ratio of drilling to the dry layer and the *** this study,by establishing the relationships between the porosity and the depth and dry layer ratio of the carbonate reservoir,the relationships between the depth and dry layer ratio were obtained *** depth corresponding to a dry layer ratio of 100%is the *** on this,a quantitative prediction model for the DLOA was finally *** results indicate that the porosity of the carbonate reservoir,Lower Ordovician in Tazhong area of Tarim Basin,tends to decrease with burial depth,and manifests as an overall low porosity reservoir in deep *** critical porosity of the DLOA was 1.8%,which is the critical geological condition corresponding to a 100%dry layer ratio encountered in the *** depth of the DLOA was 9,000 *** study provides a new method for DLOA prediction that is beneficial for a deeper understanding of oil accumulation,and is of great importance for scientific guidance on deep oil drilling.

关键词： Deep layer Tarim Basin Hydrocarbon accumulation Depth limit of oil accumulation Prediction model

Small-diameter acellular porcine corneal stroma for peripheral corneal ulceration treatment

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International Journal of Ophthalmology(English edition) 2024年第5期17卷 831-837页

作者： Tian Liang Xia wang jie Wu Yan Cheng Department of Ophthalmology Xi’an No.1 HospitalXi’an 710002Shaanxi ProvinceChina

aiM:To evaluate the clinical efficacy of small-diameter acellular porcine corneal stroma(SAPS)for the treatment of peripheral corneal ulceration(PCU).METHODS:This retrospective clinical study included 18 patients(18 eyes)with PCU between April 2018 and December *** patients had PCU and underwent lamellar keratoplasty with *** indicators included preoperative and postoperative best-corrected visual acuity(BCVA)and transparency of *** infection control rate in the surgical eye-lesion area was also ***:Eighteen patients underwent lamellar keratoplasty with SAPS to treat *** of the patients experienced rejection after 6mo(18/18)and 12mo(16/16)of *** BCVA(0.47±0.30)at the 6mo followup after operation was significantly improved compared with the baseline(0.99±0.80),and the difference was statistically significant(Z=-3.415,P<0.05).The BCVA at the 12mo follow-up after operation was not statistically significant compared to the 6mo(Z=0,P=1).With time,the SAPS graft gradually became *** the 6mo(18/18)and 12mo(16/16)follow-up,none of the patients had recurrent corneal ***:SAPS is clinically effective in the treatment of PCU,improving the patient’s BCVA and reducing the incidence of rejection after keratoplasty.

关键词： acellular porcine corneal stroma lamellar keratoplasty infectious corneal ulcer

A Novel Method for Aging Prediction of Railway Catenary Based on Improved Kalman Filter

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Structural Durability & Health Monitoring 2024年第1期18卷 73-90页

作者： jie Li Rongwen wang Yongtao Hu Jinjun Li School of Electrical Engineering and Automation Henan Institute of TechnologyXinxiang453003China Technology Center Sichuan Injet Electric Co.Ltd.Deyang618000China Embedded System Research Institute Xinxiang Engineering Research Center for Intelligent Condition Monitoring of MachineryXinxiang453003China

The aging prediction of railway catenary is of profound significance for ensuring the regular operation of electrified ***,in real-world scenarios,accurate predictions are challenging due to various *** paper addresses this challenge by proposing a novel method for predicting the aging of railway catenary based on an improved Kalman filter(KF).The proposed method focuses on modifying the priori state estimate covariance and measurement error covariance of the KF to enhance accuracy in complex *** comparing the optimal displacement value with the theoretically calculated value based on the thermal expansion effect of metals,it becomes possible to ascertain the aging status of the *** improve prediction accuracy,a railway catenary aging prediction model is constructed by integrating the Takagi-Sugeno(T-S)fuzzy neural network(FNN)and *** this model,an adaptive training method is introduced,allowing the FNN to use fewer fuzzy *** inputs of the model include time,temperature,and historical displacement,while the output is the predicted ***,the KF is enhanced by modifying its prior state estimate covariance and measurement error *** modifications contribute to more accurate ***,a low-power experimental platform based on FPGA is implemented to verify the effectiveness of the proposed *** test results demonstrate that the proposed method outperforms the compared method,showcasing its superior performance.

关键词： Railway catenary Takagi-Sugeno fuzzy neural network Kalman filter aging prediction