检索结果-南通市图书馆

Mapping upland crop–rice cropping systems for targeted sustainable intensification in South China

The Crop Journal 2024年第2期12卷 614-629页

作者： Bingwen Qiu Linhai Yu Peng Yang Wenbin Wu jianfeng chen Xiaolin Zhu Mingjie Duan Key Laboratory of Spatial Data Mining&Information Sharing of Ministry of Education Academy of Digital China(Fujian)Fuzhou UniversityFuzhou 350116FujianChina Key Laboratory of Agricultural Remote Sensing Ministry of Agriculture and Rural AffairsBeijing 100081China Department of Land Surveying and Geo-Informatics The Hong Kong Polytechnic UniversityKowloon 999077Hong KongChina

Upland crop-rice cropping systems(UCR)facilitate sustainable agricultural intensification.Accurate UCR cultivation mapping is needed to ensure food security,sustainable water management,and rural revitalization.However,datasets describing cropping systems are limited in spatial coverage and crop types.Mapping UCR is more challenging than crop identification and most existing approaches rely heavily on accurate phenology calendars and representative training samples,which limits its applications over large regions.We describe a novel algorithm(RRSS)for automatic mapping of upland crop-rice cropping systems using Sentinel-1 Synthetic Aperture Radar(SAR)and Sentinel-2 Multispectral Instrument(MSI)data.One indicator,the VV backscatter range,was proposed to discriminate UCR and another two indicators were designed by coupling greenness and pigment indices to further discriminate tobacco or oilseed UCR.The RRSS algorithm was applied to South China characterized by complex smallholder rice cropping systems and diverse topographic conditions.This study developed 10-m UCR maps of a major rice bowl in South China,the Xiang-Gan-Min(XGM)region.The performance of the RRSS algorithm was validated based on 5197 ground-truth reference sites,with an overall accuracy of 91.92%.There were7348 km^(2) areas of UCR,roughly one-half of them located in plains.The UCR was represented mainly by oilseed-UCR and tobacco-UCR,which contributed respectively 69%and 15%of UCR area.UCR patterns accounted for only one-tenth of rice production,which can be tripled by intensification from single rice cropping.Application to complex and fragmented subtropical regions suggested the spatiotemporal robustness of the RRSS algorithm,which could be further applied to generate 10-m UCR datasets for application at national or global scales.

关键词： Cropping-pattern mapping Paddy rice Sentinel-1/2 China Sustainable intensification

来源：

维普期刊数据库

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

Interface catalytic reduction of alumina by nickle for the aluminum nanowire growth: Dynamics observed by in situ TEM

引用

Nano Research 2024年第3期17卷 1225-1231页

作者： Zichun Wang Dan Wang Ang Li Lizhuo Wang Xiaodong Han Yijiao Jiang jianfeng chen Jun Huang Beijing Advanced Innovation Center for Soft Matter Science and Engineering State Key Laboratory of Organic–Inorganic CompositesBeijing University of Chemical TechnologyBeijing 100029China Laboratory for Catalysis Engineering School of Chemical and Biomolecular EngineeringThe University of SydneyNew South Wales 2006Australia Beijing Key Laboratory of Microstructure and Property of Advanced Materials Beijing University of TechnologyBeijing 100024China Department of Engineering Macquarie UniversitySydneyNew South Wales 2109Australia

Metal nanowires show promise in a broad range of applications and can be fabricated via a number of methods,such as vapor–liquid–solid process and template-based electrodeposition.However,the synthesis of Al nanowires(NWs)is still challenging from the stable alumina substrate.In this work,the Ni-catalyzed fabrication of Al NWs has been realized using various Al_(2)O_(3) substrates.The growth dynamics of Al NWs on Ni/Al_(2)O_(3) was studied using in situ transmission electron microscopy(TEM).The effect of alumina structures,compositions,and growth temperature were investigated.The growth of Al NWs correlates with the Na addition to the alumina support.Since no eutectic mixture of nickel aluminide was formed,a mechanism of Ni-catalyzed reduction of Al_(2)O_(3) for Al NWs growth has been proposed instead of the vapor–liquid–solid mechanism.The key insights reported here are not restricted to Ni-catalyzed Al NWs growth but can be extended to understanding the dynamic change and catalytic performance of Ni/Al_(2)O_(3) under working conditions.

关键词： in situ transmission electron microscopy(TEM) Al nanowires alumina reduction nanowire growth

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

A Deep Learning Framework for Mass-Forming Chronic Pancreatitis and Pancreatic Ductal Adenocarcinoma Classification Based on Magnetic Resonance Imaging

引用

Computers, Materials & Continua 2024年第4期79卷 409-427页

作者： Luda chen Kuangzhu Bao Ying chen Jingang Hao jianfeng He Faculty of Information Engineering and Automation Kunming University of Science and TechnologyKunming650504China Department of Radiology Second Affiliated Hospital of Kunming Medical UniversityKunming650101China School of Physics and Electronic Engineering Yuxi Normal UniversityYuxi653100China

Pancreatic diseases, including mass-forming chronic pancreatitis (MFCP) and pancreatic ductal adenocarcinoma(PDAC), present with similar imaging features, leading to diagnostic complexities. Deep Learning (DL) methodshave been shown to perform well on diagnostic tasks. Existing DL pancreatic lesion diagnosis studies basedon Magnetic Resonance Imaging (MRI) utilize the prior information to guide models to focus on the lesionregion. However, over-reliance on prior information may ignore the background information that is helpful fordiagnosis. This study verifies the diagnostic significance of the background information using a clinical dataset.Consequently, the Prior Difference Guidance Network (PDGNet) is proposed, merging decoupled lesion andbackground information via the Prior Normalization Fusion (PNF) strategy and the Feature Difference Guidance(FDG) module, to direct the model to concentrate on beneficial regions for diagnosis. Extensive experiments inthe clinical dataset demonstrate that the proposed method achieves promising diagnosis performance: PDGNetsbased on conventional networks record an ACC (Accuracy) and AUC (Area Under the Curve) of 87.50% and89.98%, marking improvements of 8.19% and 7.64% over the prior-free benchmark. Compared to lesion-focusedbenchmarks, the uplift is 6.14% and 6.02%. PDGNets based on advanced networks reach an ACC and AUC of89.77% and 92.80%. The study underscores the potential of harnessing background information in medical imagediagnosis, suggesting a more holistic view for future research.

关键词： Pancreatic cancer pancreatitis background region prior normalization fusion feature difference guidance

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Application of epoxy resin in cultural relics protection

引用

Chinese Chemical Letters 2024年第4期35卷 31-42页

作者： Zhaoru chen Xiaoxu Liu Haonan chen Jialong Li Xiaofeng Wang jianfeng Zhu Shaanxi Key Laboratory of Green Preparation and Functionalization for Inorganic Materials School of Material Science and EngineeringShaanxi University of Science and TechnologyXi'an 710021China College of Mechanical&Electrical Engineering Shaanxi University of Science and TechnologyXi'an 710021China

Cultural relics have their unique artistic, cultural and historical value, and the protection of important cultural relics is conducive to the inheritance of historical culture. As a kind of cementing agent and binder commonly seen in cultural relics protection, epoxy resin is widely used in the bonding and consolidation of various materials in cultural relics, which has important practical application value. In this review, a systematic classification of commonly used epoxy resins, including their molecular structures, synthesis reactions and properties are provided, the problems and solutions of epoxy resin in cultural relics protection are summarized. The solutions are classified into three aspects: functional epoxy resin, blending modification, and other modification. Representative application examples of epoxy resin are listed in the field of cultural relics protection, and the development direction of epoxy resin in cultural relics protection in the future is proposed, which provides useful guidance for the modification of epoxy resin and its application in cultural relics protection in the future.

关键词： Epoxy resin Cultural relics Modified UV resistance

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Creep constitutive model considering nonlinear creep degradation of fractured rock

引用

International Journal of Mining Science and Technology 2024年第1期34卷 105-116页

作者： Wang Chunping Liu jianfeng chen Liang Liu Jian Wang Lu Liao Yilin Beijing Research Institute of Uranium Geology Beijing 100029China CAEA Innovation Center for Geological Disposal of High-Level Radioactive Waste Beijing 100029China State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan UniversityChengdu 610065China School of Architecture and Civil Engineering Xihua UniversityChengdu 610039China

Stability analysis of underground constructions requires a model study of rock masses’ long-term performance. Creep tests under different stress conditions was conducted on intact granite and granite samples fractured at 30° and 45° angles. The experimental results indicate that the steady creep strain rates of intact and fractured rock present an exponential increase trend with the increase of stress level. A nonlinear creep model is developed based on the experimental results, in which the initial damage caused by fracture together with the damage caused by constant load have been taken into consideration. The fitting analysis results indicated that the model proposed is more accurate at identifying the full creep regions in fractured granite, especially the accelerated stage of creep deformation. The least-square fit error of the proposed creep model is significantly lower than that of Nishihara model by almost an order of magnitude. An analysis of the effects of elastic modulus, viscosity coefficient, and damage factors on fractured rock strain rate and creep strain is conducted. If no consideration is given to the effects of the damage, the proposed nonlinear creep model can degenerate into to the classical Nishihara model.

关键词： Fractured rock Damage Creep Beishan granite Geological disposal

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Nonlinear Impact Damage Evolution of Charpy Type and Analysis of Its Key Influencing Factors

引用

Chinese Journal of Mechanical Engineering 2024年第1期37卷 254-264页

作者： jianfeng Mao Qian Xu Jiadong Yang Chi Cao Dasheng Wang Fengping Zhong Mingya chen Institute of Process Equipment and Control Engineering Zhejiang University of TechnologyHangzhou 310032China Taizhou Key Laboratory of Advanced Manufacturing Technology Taizhou InstituteZhejiang University of TechnologyTaizhou 318014China State Key Laboratory of Nuclear Power Safety Monitoring Technology and Equipment Shenzhen 518172China Zhejiang Academy of Special Equipment Science Hangzhou 310020China Suzhou Nuclear Power Research Institute Suzhou 215004China

The current research of Charpy impact mainly focuses on obtaining the ductile brittle transition temperature of materials by experiments.Compared with experiments,numerical simulation can study many problems with harsh conditions.However,there are still few studies on the influence of geometric factors such as side grooves.In this paper,the geometry of standard Charpy impact test is designed.Specimens with different widths and side grooves are tested.The finite element model of Charpy impact was established by ABAQUS software.Use test results and simulation results to verify each other.The effects of sample width,side groove depth and side groove bottom fillet on the impact fracture resistance of the sample were studied.The results show that the specimen width is positively correlated with the impact toughness of the specimen.The side groove greatly reduces the impact toughness of the material;the toughness of side groove decreases with the increase of depth;the fracture toughness of side groove decreases with the increase of fillet at the bottom of side groove.The proportion of toughness energy to impact energy of samples was analyzed.The results show that the toughness energy accounts for about 70%of the impact energy of the sample,which has little to do with the geometric characteristics of the sample.This study presents a reliable method for studying Charpy impact tests.The influence of geometric parameters is obtained,which provides a reference method for the study of impact toughness of high toughness materials.

关键词： Johnson-Cook model Impact toughness Charpy impact

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

A mite parasitoid,Pyemotes zhonghuajia,negatively impacts the fitness traits and immune response of the fall armyworm,Spodoptera frugiperda

引用

Journal of Integrative Agriculture 2024年第1期23卷 205-216页

作者： Yanfei Song Tai’an Tian Yichai chen Keshi Zhang Maofa Yang jianfeng Liu Institute of Entomology Guizhou Provincial Key Laboratory for Agricultural Pest Management of the Mountainous RegionGuizhou University/Scientific Observing and Experiment Station of Crop Pests in GuiyangMinistry of Agriculture and Rural AffairsGuiyang 550025China Administration of Guizhou Fanjingshan National Nature Reserve Jiangkou 554400China Centre for Biodiversity and Biosecurity School of Biological SciencesThe University of AucklandAuckland 1072New Zealand College of Tobacco Science Guizhou UniversityGuiyang 550025China

Parasitoids are key regulators in ecological communities and widely used as agents in biocontrol programmes.The fall armyworm,Spodoptera frugiperda,recently invaded multiple continents and caused substantial economic losses in agriculture.Pyemotes zhonghuajia,a newly identified mite parasitoid,has shown potential for controlling various agricultural insect pests.Therefore,this study tested the performance of P.zhonghuajia in parasitising S.frugiperda.We also investigated the sublethal effects of parasitism by P.zhonghuajia on host fitness traits,transgenerational impacts,and cellular and humoral immunity.Our result showed that the fifth-instar larvae of S.frugiperda parasitised by 40 P.zhonghuajia were all dead(i.e.,a lethal effect),while parasitism by 5 or 10 P.zhonghuajia was considered sublethal since many S.frugiperda survived to adulthood and produced offspring after mating.The sublethal influences from parasitism by P.zhonghuajia resulted in reduced pupal weight,adult emergence rate and fecundity,but increased developmental time and longevity.Parasitism at both lethal(40 mites)and sublethal(10 mites)levels impaired the cellular and humoral immunity of S.frugiperda.This study presents the first empirical evidence that mite parasitoids can negatively influence host immunity.Moreover,it provides insights into the biocontrol potential of mite parasitoids and their interactions with hosts.

关键词： Pyemotes zhonghuajia Spodoptera frugiperda immunity parasitically-induced influence biocontrol parasitoid

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Prognostic value of time-varying dead space estimates in mechanically ventilated patients with acute respiratory distress syndrome

引用

Journal of Intensive Medicine 2024年第2期4卷 187-193页

作者： Lianlian Jiang Hui chen jianfeng Xie Ling Liu Yi Yang Jiangsu Provincial Key Laboratory of Critical Care Medicine Department of Critical Care MedicineZhongda HospitalSchool of MedicineSoutheast UniversityNanjingJiangsuChina Department of Critical Care Medicine The First Affiliated Hospital of Soochow UniversitySoochow UniversitySuzhouJiangsuChina

Background The dead space fraction(VD/VT)has proven to be a powerful predictor of higher mortality in acute respiratory distress syndrome(ARDS).However,its measurement relies on expired carbon dioxide,limiting its widespread application in clinical practice.Several estimates employing routine variables have been found to be reliable substitutes for direct measurement of VD/VT.In this study,we evaluated the prognostic value of these dead space estimates obtained in the first 7 days following the initiation of ventilation.Methods This retrospective observational study was conducted using data from the Chinese database in intensive care(CDIC).Eligible participants were adult ARDS patients receiving invasive mechanical ventilation while in the intensive care unit between 1st January 2014 and 31st March 2021.We collected data during the first 7 days of ventilation to calculate various dead space estimates,including ventilatory ratio(VR),corrected minute ventilation(V_(Ecorr)),VD/VT(Harris–Benedict),VD/VT(Siddiki estimate),and VD/VT(Penn State estimate)longitudinally.A time-dependent Cox model was used to handle these time-varying estimates.Results A total of 392 patients(median age 66[interquartile range:55–77]years,median SOFA score 9[interquartile range:7–12])were finally included in our analysis,among whom 132(33.7%)patients died within 28 days of admission.VR(hazard ratio[HR]=1.04 per 0.1 increase,95%confidence interval[CI]:1.01 to 1.06;P=0.013),V_(Ecorr)(HR=1.08 per 1 increase,95%CI:1.04 to 1.12;P1.3,V_(Ecorr)>7.53,and VD/VT(Harris–Benedict)>0.59 was independently

关键词： Acute respiratory distress syndr ome Mechanical ventilation Dead space 28-day mortality

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

A creep model for ultra-deep salt rock considering thermal-mechanical damage under triaxial stress conditions

引用

Journal of Rock Mechanics and Geotechnical Engineering 2024年第2期16卷 588-596页

作者： Chao Liang jianfeng Liu Jianxiong Yang Huining Xu Zhaowei chen Lina Ran College of Water Resource and Hydropower Sichuan UniversityChengdu610065China CNPC Key Laboratory of Oil and Gas Underground Storage Engineering Langfang065007China CNPC Engineering Technology R&D Company Limited Beijing102206China

To investigate the specific creep behavior of ultra-deep buried salt during oil and gas exploitation,a set of triaxial creep experiments was conducted at elevated temperatures with constant axial pressure and unloading confining pressure conditions.Experimental results show that the salt sample deforms more significantly with the increase of applied temperature and deviatoric loading.The accelerated creep phase is not occurring until the applied temperature reaches 130℃,and higher temperature is beneficial to the occurrence of accelerated creep.To describe the specific creep behavior,a novel three-dimensional(3D)creep constitutive model is developed that incorporates the thermal and mechanical variables into mechanical elements.Subsequently,the standard particle swarm optimization(SPSO)method is adopted to fit the experimental data,and the sensibility of key model parameters is analyzed to further illustrate the model function.As a result,the model can accurately predict the creep behavior of salt under the coupled thermo-mechanical effect in deep-buried condition.Based on the research results,the creep mechanical behavior of wellbore shrinkage is predicted in deep drilling projects crossing salt layer,which has practical implications for deep rock mechanics problems.

关键词： Creep experiments Creep model Thermal and mechanical damage Fractional derivative

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Genetic variants in the 6p21.3 region influence hepatitis B virus clearance and chronic hepatitis B risk in the Han Chinese population

引用

Liver Research 2024年第1期8卷 54-60页

作者： Jiancheng Huang Mingkuan Su Fanhui Kong Hongbin chen Shuiqing Wu jianfeng Guo Haiying Wu Department of Laboratory Medicine Mindong Hospital Affiliated to Fujian Medical UniversityFuanFujianChina Department of Gastroenterology Mindong Hospital Affiliated to Fujian Medical UniversityFuanFujianChina

Background and aim:A genome-wide association study has indicated the association of numerous genes in the 6p21.3 region with chronic hepatitis B virus(HBV)infection.In this study,we screened 12 representative single-nucleotide polymorphisms(SNPs)from the 6p21.3 region and investigated their association with the risk of chronic hepatitis B(CHB)to better understand the molecular etiology un-derlying CHB risk in the Han Chinese population.Methods:Between March 2021 and November 2022,we included 183 patients with CHB(case group)and 196 with natural HBV clearance(control group).Allele typing of the selected SNPs was performed using snapshot technology.The correlation between the 12 chosen SNPs and the risk of chronic HBV infection was examined using binary logistic regression analysis.Interacting genes of the variants were identified,and expression quantitative trait loci(eQTL)were analyzed using the 3DSNP database.Results:We validated 12 previously reported CHB susceptibility sites,including rs1419881 of tran-scription factor 19(TCF19),rs3130542 and rs2853953 of human leukocyte antigen(HLA)-C,rs652888 of euchromatic histone-lysine-methyltransferase 2(EHMT2),rs2856718,rs9276370,rs7756516,and rs7453920 of HLA-DQ,rs378352 of HLA-DOA,and rs3077,rs9277535,and rs9366816 of HLA-DP.Logistic regression analyses revealed that polymorphisms such as rs9276370,rs7756516,rs7453920,rs3077,rs9277535,and rs9366816 were positively correlated with natural HBV clearance in the dominant model.Conversely,rs3130542 and rs378352 were identified as risk factors for CHB.Haplotype analysis revealed that rs9276370,rs7756516,and rs7453920 in HLA-DQ were TTG and GCA haplotypes.Although the TTG haplotype was positively correlated with a higher risk of CHB,the GCA haplotype significantly influenced the natural clearance of HBV.Bioinformatics analysis demonstrated that rs378352,rs3077,and rs9366816 were located within enhancer states;rs3077 and rs9366816 overlapped with nine tran-scription factor-binding sites,whereas rs378352 altered five sequence

关键词： Chronic hepatitis B(CHB) Expression quantitative trait loci(eQTL) Haplotype Hepatitis B virus(HBV) Human leukocyte antigen(HLA) Single-nucleotide polymorphism(SNP)

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：