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Journal of Earth Science 2024年第4期35卷 1186-1195页

作者： Yangyang Zhang Yuelong Chen Dapeng Li Huan kang Mingliang Fang Yunliang xu School of Earth Science and Resources China University of GeosciencesBeijing100083China State Key Laboratory of Earthquake Dynamics Institute of GeologyChina Earthquake AdministrationBeijing100083China Jinchuan Group Company Limited Jinchang737104China China-Explo Tian Cheng(Beijing)Technology Company Limited Beijing100093China

Radon(Rn)and helium(He)gases from uranium decay form distinct anomalies related to buried uranium *** order to trace the geochemical anomalous sources from the volcanic-related uranium deposits in deeply buried areas,systematical Rn contents and He isotope ratios were analyzed from the Daguanchang uranium *** soil gas Rn concentrations above the deep uranium are ten times higher than those in barren areas,indicating that instantaneous Rn content measurements can be used to detect deeply buried *** helium isotope ratios(^(3)He/^(4)He)of the unmineralized samples from the mineralized drill hole(ZK1)are relatively lower and uniform compared to those of the samples from no-mineral drill hole(ZK2).However,the Th and U contents of the drill core samples from ZK1 are slightly lower than those of the samples from ZK2,indicating that the lower 3He/4He ratios in ZK1 are most likely due to the addition of 4He from underlying uranium *** differences in the instantaneous Rn contents are consistent with the variations in the He isotope ratios of the drill core *** results demonstrate that soil gas Rn and ^(3)He/^(4)He ratios are useful tracers and can indicate the existence of deeply buried volcanic-related hydrothermal uranium ores.

关键词： tracers radon helium ^(3)He/^(4)He ratio uranium deposits Daguanchang deposit

Improving fatigue properties of normal direction ultrasonic vibration assisted face grinding Inconel 718 by regulating machined surface integrity

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International Journal of Extreme Manufacturing 2024年第3期6卷 458-475页

作者： Nianwei xu Renke kang Bi Zhang Yuan Zhang Chenxu Wang Yan Bao Zhigang Dong State Key Laboratory of High-Performance Precision Manufacturing Dalian University of TechnologyDalian 116024People’s Republic of China Department of Mechanical and Energy Engineering Southern University of Science and TechnologyShenzhen 518055People’s Republic of China

Fatigue properties are crucial for critical aero-engine components in extreme serviceenvironments,which are significantly affected by surface integrity(SI)indexes(especially surface topography,residual stressσ_(res),and microhardness)after machining ***-direction ultrasonic vibration-assisted face grinding(ND-UVAFG)has advantages in improving the machinability of Inconel 718,but there is a competitive relationship between higher compressiveσ_(res)and higher surface roughness R_(a)in affecting fatigue *** lack of a quantitative relationship between multiple SI indexes and fatigue strength makes theindeterminacy of a regulatory strategy for improving fatigue *** this work,a model of fatigue strength(σ_f)_(sur)considering multiple SI indexes was ***,high-cycle fatigue tests were carried out on Inconel 718 samples with different SI characteristics,and the influence of ND-UVAFG process parameters on SI was *** on SI indexes data,the(σ_f)_(sur)distribution in the grinding surface layer for ND-UVAFG Inconel 718 samples was determined using the developed model,and then the fatigue crack initiation(FCI)sites were *** predicted FCI sites corresponded well with the experimental results,therebyverifying this model.A strategy for improving the fatigue life was proposed in this work,which was to transfer the fatigue source from the machined surface to the bulk material by controlling the SI ***,a critical condition of SI indexes that FCI sites appeared on the surface or in bulk material was given by fitting the predicted *** to the critical condition,an SI field where FCI sites appeared in the bulk material could be *** this field,thefatigue life of Inconel 718 samples could be improved by approximately 140%.

关键词： surface integrity fatigue strength Inconel 718 ultrasonic assisted grinding

Micropillar compression using discrete dislocation dynamics and machine learning

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Theoretical & Applied Mechanics Letters 2024年第1期14卷 39-47页

作者： Jin Tao Dean Wei Junshi Yu Qianhua Kan Guozheng kang xu Zhang School of Mechanics and Aerospace Engineering Southwest Jiaotong UniversityChengdu 610031China State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing 100190China

Discrete dislocation dynamics(DDD)simulations reveal the evolution of dislocation structures and the interaction of *** study investigated the compression behavior of single-crystal copper micropillars using fewshot machine learning with data provided by DDD *** types of features are considered:external features comprising specimen size and loading orientation and internal features involving dislocation source length,Schmid factor,the orientation of the most easily activated dislocations and their distance from the free *** yielding stress and stress-strain curves of single-crystal copper micropillar are predicted well by incorporating both external and internal features of the sample as separate or combined *** is found that the machine learning accuracy predictions for single-crystal micropillar compression can be improved by incorporating easily activated dislocation features with external ***,the effect of easily activated dislocation on yielding is less important compared to the effects of specimen size and Schmid factor which includes information of orientation but becomes more evident in small-sized ***,incorporating internal features,especially the information of most easily activated dislocations,improves predictive capabilities across diverse sample sizes and orientations.

关键词： Discrete dislocation dynamics simulations Machine learning Size effects Orientation effects Microstructural features

Photo-induced tunable luminescence from an aggregated amphiphilic ethylene-pyrene derivative in aqueous media

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Chinese Chemical Letters 2024年第6期35卷 303-306页

作者： Junying Zhang Ruochen Li Haihua Wang Wenbing kang Xing-Dong xu National Engineering Research Center for Colloidal Materials Key Laboratory of Special Functional Aggregated Materials of Ministry of EducationShandong Key Laboratory of Advanced Silicone Materials and TechnologySchool of Chemistry and Chemical EngineeringShandong UniversityJi’nan 250100China

An amphiphilic derivative with a large Stokes shift by introducing flexible hydrophilic long chains into a rigid ethylene-pyrene compound have been successfully *** alkylated compound exhibited a notable change in charge distribution,facilitating cation-π *** the process of amphiphilic self-assembly,the formation of highly ordered aggregates enabled effective photo-dimerization under 449 nm LED ***,this photo-responsive technology not only exhibited advanced multi-color emission effects,including white light emission but also exhibited environmentally friendly behavior in the aqueous phase.

关键词： Supramolecular chemistry Amphiphilic assembly Stimuli-responsive materials Tunable luminescence Pyrene derivative

Comprehensive applicability evaluation of four precipitation products at multiple spatiotemporal scales in Northwest China

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Journal of Arid Land 2024年第9期16卷 1232-1254页

作者： WANG Xiangyu xu Min kang Shichang LI xuemei HAN Haidong LI Xingdong School of Mathematics Lanzhou Jiaotong UniversityLanzhou 730070China Key Laboratory of Cryospheric Science and Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China Faculty of Geomatics Lanzhou Jiaotong UniversityLanzhou 730070China

Precipitation plays a crucial role in the water cycle of Northwest *** accurate precipitation data is crucial for regional water resource management,hydrological forecasting,flood control and drought ***,the applicability of multi-source precipitation products for long time series in Northwest China has not been thoroughly *** this study,precipitation data from 183 meteorological stations in Northwest China from 1979 to 2020 were selected to assess the regional applicability of four precipitation products(the fifth generation of European Centre for Medium-Range Weather Forecasts(ECMWF)atmospheric reanalysis of the global climate(ERA5),Global Precipitation Climatology Centre(GPCC),Climatic Research Unit gridded Time Series Version 4.07(CRU TS v4.07,hereafter CRU),and Tropical Rainfall Measuring Mission(TRMM))based on the following statistical indicators:correlation coefficient,root mean square error(RMSE),relative bias(RB),mean absolute error(MAE),probability of detection(POD),false alarm ratio(FAR),and equitable threat score(ETS).The results showed that precipitation in Northwest China was generally high in the east and low in the west,and exhibited an increasing trend from 1979 to *** with the station observations,ERA5 showed a larger spatial distribution difference than the other *** overall overestimation of multi-year average precipitation was approximately 200.00 mm and the degree of overestimation increased with increasing precipitation *** multi-year average precipitation of GPCC and CRU was relatively close to that of station *** trend of annual precipitation of TRMM was overestimated in high-altitude regions and the eastern part of Lanzhou with more *** the monthly scale,GPCC performed well but underestimated precipitation in the Tarim Basin(RB=-4.11%),while ERA5 and TRMM exhibited poor accuracy in high-altitude ***5 had a large bias(RB≥120.00%)in winter months

关键词： precipitation products the fifth generation of European Centre for Medium-Range Weather Forecasts(ECMWF)atmospheric reanalysis of the global climate(ERA5) Global Precipitation Climatology Centre(GPCC) Climatic Research Unit gridded Time Series(CRU TS) Tropical Rainfall Measuring Mission(TRMM) applicability evaluation Northwest China

Low interleukin-10 level indicates a good prognosis in Salmonella enterica serovar typhimurium-induced pediatric hemophagocytic lymphohistiocytosis:A case report

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World Journal of Clinical Cases 2024年第9期12卷 1660-1668页

作者： Yuan-Yuan Chen Xiang-Zhi xu xiao-Jun xu Division/Center of Pediatric Hematology Oncology Children’s HospitalZhejiang University School of MedicineHangzhou 310003Zhejiang ProvinceChina Pediatric Intensive Care Unit Children’s Hospital of Zhejiang University School of MedicineHangzhou 310003Zhejiang ProvinceChina

BACKGROUND Secondary hemophagocytic lymphohistiocytosis(sHLH)triggered by Salmonella enterica serovar Typhimurium is rare in pediatric *** is no consensus on how to treat ***-triggered *** SUMMARY A 9-year-old boy with intermittent fever for 3 d presented to our hospital with positive results for ***,human rhinovirus,and Mycoplasma pneumoniae *** the time of admission to our institution,the patient’s T helper 1/T helper 2 cytokine levels were 326 pg/mL for interleukin 6(IL-6),9.1 pg/mL for IL-10,and 246.7 pg/mL for interferon-gamma(IFN-γ),for which the ratio of IL-10 to IFN-γwas *** this study,the patient received meropenem,linezolid,and cefoperazone/sulbactam in combination with high-dose methylprednisolone therapy(10 mg/kg/d for 3 d)and antishock supportive treatment *** careful evaluation,this patient did not receive HLH chemotherapy and recovered *** *** infection-triggered sHLH patient had a ratio of IL-10 to IFN-γ≤1.33,an IL-10 concentration≤10.0 pg/mL,and/or an IFN-γconcentration≤225 pg/mL at *** antimicrobial and supportive treatment was sufficient,and the HLH-94/2004 protocol was not necessary under these conditions.

关键词： Hemophagocytic lymphohistiocytosis Cytokine pattern Interferon gamma Interleukin-10 Salmonella enterica serovar Typhimurium Case report

Development and validation of a nomogram for predicting in-hospital mortality of intensive care unit patients with liver cirrhosis

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World Journal of Hepatology 2024年第4期16卷 625-639页

作者： xiao-Wei Tang Wen-Sen Ren Shu Huang kang Zou Huan xu xiao-Min Shi Wei Zhang Lei Shi Mu-Han Lü Department of Gastroenterology The Affiliated Hospital of Southwest Medical UniversityLuzhou 646099Sichuan ProvinceChina Nuclear Medicine and Molecular Imaging Key Laboratory The Affiliated Hospital of Southwest Medical UniversityLuzhou 646099Sichuan ProvinceChina Department of Gastroenterology Lianshui People’Hospital of Kangda College Affiliated to Nanjing Medical UniversityHuaian 223499Jiangsu ProvinceChina

BACKGROUND Liver cirrhosis patients admitted to intensive care unit(ICU)have a high mortality *** To establish and validate a nomogram for predicting in-hospital mortality of ICU patients with liver *** We extracted demographic,etiological,vital sign,laboratory test,comorbidity,complication,treatment,and severity score data of liver cirrhosis patients from the Medical Information Mart for Intensive Care IV(MIMIC-IV)and electronic ICU(eICU)collaborative research database(eICU-CRD).Predictor selection and model building were based on the MIMIC-IV *** variables selected through least absolute shrinkage and selection operator analysis were further screened through multivariate regression analysis to obtain final *** final predictors were included in the multivariate logistic regression model,which was used to construct a ***,we conducted external validation using the *** area under the receiver operating characteristic curve(AUC),decision curve,and calibration curve were used to assess the efficacy of the *** Risk factors,including the mean respiratory rate,mean systolic blood pressure,mean heart rate,white blood cells,international normalized ratio,total bilirubin,age,invasive ventilation,vasopressor use,maximum stage of acute kidney injury,and sequential organ failure assessment score,were included in the multivariate logistic *** model achieved AUCs of 0.864 and 0.808 in the MIMIC-IV and eICU-CRD databases,*** calibration curve also confirmed the predictive ability of the model,while the decision curve confirmed its clinical *** The nomogram has high accuracy in predicting in-hospital *** the included predictors may help improve the prognosis of patients.

关键词： Liver cirrhosis Intensive care unit Nomogram Predicting model Mortality

Facile synthesis of hierarchical NaX zeolite from natural kaolinite for efficient Knoevenagel condensation

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Chinese Journal of Chemical Engineering 2024年第1期65卷 75-84页

作者： Wen xiao Peng Dong Chan Wang Jingdong xu Tiesen Li Haibo Zhu Tinghai Wang Renwei xu Yuanyuan Yue National Engineering Research Center of Chemical Fertilizer Catalyst College of Chemical EngineeringFuzhou UniversityFuzhou 350108China Qingyuan Innovation Laboratory Quanzhou 362801China Sinochem Quanzhou Energy Technology Co. Ltd.Quanzhou 362000China

Zeolite catalysts have found extensive applications in the synthesis of various fine ***,the micropores of zeolites impose diffusion limitations on bulky molecules,greatly reducing the catalytic ***,we explore an economic and environmentally friendly method for synthesizing hierarchical NaX zeolite that exhibits improved catalytic performance in the Knoevenagel condensation reaction for producing the useful fine chemical *** synthesis was achieved via a low-temperature activation of kaolinite and subsequent in-situ transformation strategy without any template or *** characterizations reveal that the synthesized NaX zeolite has both intercrystalline and intra-crystalline mesopores,smaller crystal size,and larger external specific surface area compared to commercial NaX *** mechanism investigations show that the inter-crystalline mesopores are generated by stacking smaller crystals formed from in-situ crystallization of the depolymerized kaolinite,and the intra-crystalline mesopores are inherited from the pores in the depolymerized *** synthesis strategy provides an energy-saving and effective way to construct hierarchical zeolites,which may gain wide applications in fine chemical manufacturing.

关键词： Hierarchical NaX zeolite Template-free synthesis Natural kaolinite Knoevenagel condensation

Understanding the Interfacial Energy Structure and Electron Extraction Process in Inverted Organic Solar Cells with Phosphine-Doped Cathode Interlayers

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Chinese Journal of Chemistry 2024年第12期42卷 1347-1354页

作者： Yi Yang Jingwen Wang Yang xiao Bowei xu Jianhui Hou State Key Laboratory of Polymer Physics and Chemistry Beijing National Laboratory for Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China State Key Laboratory of Chemical Resource Engineering College of Materials Science and EngineeringBeijing University of Chemical TechnologyBejing 100029China University of Chinese Academy of Sciences Beijing 100049China

Comprehensive Summary Cathode interlayers(CILs)play an essential role in achieving efficient organic solar cells(OSCs).However,the electronic structure at the electrode/CIL/active layer interfaces and the underlying mechanisms for electron collection remain unclear,which becomes a major obstacle to develop high-performance ***,we investigate the relationship of the electron collection abilities of four cross-linked and n-doped CILs(c-NDI:P0,c-NDI:P1,c-NDI:P2,c-NDI:P3)with their electronic structure of space charge region at heterojunction *** accurately calculating the depletion region width according to the barrier height,doping density and permittivity,we put forward that the optimal thickness of CIL should be consistent with the depletion region width to realize the minimum energy *** a result,the depletion region width is largely reduced from 13 nm to 0.8 nm at the indium tin oxide(ITO)/c-NDI:P0 interface,resulting in a decent PCE of 17.7%for the corresponding inverted OSCs.

关键词： Organic solar cells Cathode interlayer Depletion region width Electric conductivity Electron transport Electron transfer Electron extraction process

MdbHLH162 connects the gibberellin and jasmonic acid signals to regulate anthocyanin biosynthesis in apple

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Journal of Integrative Plant Biology 2024年第2期66卷 265-284页

作者： Jian-Ping An Rui-Rui xu xiao-Na Wang xiao-Wei Zhang Chun-Xiang You Yuepeng Han Apple technology innovation center of Shandong Province College of Horticulture Science and EngineeringShandong Agricultural UniversityTai-An 271018China CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture Wuhan Botanical GardenHubei Hongshan LaboratoryThe Innovative Academy of Seed Design of Chinese Academy of SciencesWuhan 430074China College of Biology and Oceanography Weifang UniversityWeifang 261061China

Anthocyanins are secondary metabolites induced by environmental stimuli and developmental *** positive regulators of anthocyanin biosynthesis have been reported,whereas the anthocyanin repressors have been *** the signal transduction pathways of gibberellin(GA)and jasmonic acid(JA)and their regulation of anthocyanin biosynthesis have been investigated,the cross-talk between GA and JA and the antagonistic mechanism of regulating anthocyanin biosynthesis remain to be *** this study,we identified the anthocyanin repressor MdbHLH162 in apple and revealed its molecular mechanism of regulating anthocyanin biosynthesis by integrating the GA and JA ***162 exerted passive repression by interacting with MdbHLH3 and MdbHLH33,which are two recognized positive regulators of anthocyanin ***162 negatively regulated anthocyanin biosynthesis by disrupting the formation of the anthocyanin-activated MdMYB1-MdbHLH3/33complexes and weakening transcriptional activation of the anthocyanin biosynthetic genes MdDFR and MdUF3GT by MdbHLH3 and *** GA repressor MdRGL2a antagonized MdbHLH162-mediated inhibition of anthocyanins by sequestering MdbHLH162 from the MdbHLH162-MdbHLH3/33 *** JA repressors MdJAZ1 and MdJAZ2 interfered with the antagonistic regulation of MdbHLH162 by MdRGL2a by titrating the formation of the MdRGL2a-MdbHLH162 *** findings reveal that MdbHLH162 integrates the GA and JA signals to negatively regulate anthocyanin *** study provides new information for discovering more anthocyanin biosynthesis repressors and explores the cross-talk between hormone signals.

关键词： anthocyanin biosynthesis bHLH transcription factor gibberellin jasmonic acid regulatory network transcriptional regulation