检索结果-南通市图书馆

Wheat straw return can lead to biogenic toluene emissions

Journal of Environmental Sciences 2023年第2期124卷 281-290页

作者： Ting Wu Xiaoyu zhao Mengdi Liu Juan zhao xinming Wang School of Ecology and Environment Anhui Normal UniversityWuhu 241000China Center of Cooperative Innovation for Recovery and Reconstruction of Degraded Ecosystem in Wanjiang City Belt Wuhu 241000China State Key Laboratory of Organic Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China

As a common practice in agricultural system,straw return has been reported to release a large number of trace gases and attractedmuch attention.However,the role of straw return in toluene emission remains poorly understood.In this study we measured the emissions of toluene as well as other 50 volatile organic compounds(VOCs)from wheat straw return for 66 days under flooded and non-flooded conditions,respectively.The results showed that substantial toluene was released from the returned wheat straw particularly under flooded condition,and primarily derived from the secondary product.Toluene emissions from the returned wheat straw were 36.8 and 8.45 mg C/kg,sharing 28.0%and 8.6%of total VOCs released,and over 90% of toluene emissions occurred between days 24-56 and 0-17 under flooded and non-flooded conditions,respectively.The emission rates of toluene were relatively high but decreased sharply at the beginning 2 days,and then was steady until 24 days under the two moisture conditions.After the initial decrease these rose again to form one“peak emission window”between days 24-56 under flooded condition,while these were still very low and steady until the end under non-flooded condition.The toluene emission rates significantly positively correlated with microbial biomass C under flooded condition,but negatively associated with bacteria and fungus number,microbial biomass C,and CO_(2) flux under non-flooded condition,suggesting that microorganism might play an important role in toluene emissions from wheat straw return.A rough estimate indicated that straw return might be important for biogenic toluene.

关键词： Toluene Boigenic volatile organic compounds(BVOCs) Emission profile Straw return

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

Simultaneous enhancement in mechanical and corrosion properties of Al-Mg-Si alloys using machine learning

引用

Journal of Materials Science & Technology 2023年第36期167卷 1-13页

作者： xinming Feng Zhilei Wang Lei Jiang Fan zhao Zhihao Zhang Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China Beijing Laboratory of Metallic Materials and Processing for Modern Transportation Institute for Advanced Materials and TechnologyUniversity of Science and Technology BeijingBeijing 100083China Key Laboratory for Advanced Materials Processing(MOE) University of Science and Technology BeijingBeijing 100083China Beijing Advanced Innovation Center for Materials Genome Engineering Institute for Advanced Materials and TechnologyUniversity of Science and Technology BeijingBeijing 100083China

Al-Mg-Si alloys with high strength and good corrosion resistance are regarded as desirable materials for all-aluminum vehicles.However,the traditional trial-and-error experimental methods are insufficient to address the trade-offbetween strength and corrosion resistance.In this work,a non-dominated sorting genetic machine-learning algorithm(NSGA-II)was employed to optimize the chemical composition,so as to simultaneously improve the strength and corrosion resistance.Three high-performance Al-Mg-Si alloys with low Mg,Si,and Cu contents were successfully developed,where the yield strength(YS),ultimate tensile strength(UTS),and the elongation(δ)reached 375-380 MPa,410-416 MPa,and 13.7%-15.2%,re-spectively.Compared with higher-Cu-content 6013 alloy,the YS and UTS of the present alloys increase by about 60 MPa,and the intergranular corrosion resistance is also significantly improved.Microstruc-ture characterization demonstrated thatβ’’and QP phases introduced a significant synergistic precipita-tion strengthening effect;the dispersoids formed by trace Mn,Cr,Fe,Zr,and Ti contributed dispersion strengthening effect;and the good pitting corrosion resistance is attributed to lower Mg and Si contents.

关键词： Aluminum alloy Machine learning High strength Corrosion resistance

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

Histogram analysis of apparent diffusion coefficient predicts response to radiofrequency ablation in hepatocellular carcinoma

引用

Chinese Journal of Cancer Research 2019年第2期31卷 366-374页

作者： Xiaohong Ma Han Ouyang Shuang Wang Meng Wang Chunwu Zhou Xinming Zhao Department of Diagnostic Radiology National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital Chinese Academy of Medical Sciences Peking Union Medical College Department of Epidemiology National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital Chinese Academy of Medical Sciences Peking Union Medical College

Objective: The aim of this study was to predict tumor progression in patients with hepatocellular carcinoma(HCC) treated with radiofrequency ablation(RFA) using histogram analysis of apparent diffusion coefficients(ADC).Methods: Breath-hold diffusion weighted imaging(DWI) was performed in 64 patients(33 progressive and 31 stable) with biopsy-proven HCC prior to RFA. All patients had pre-treatment magnetic resonance imaging(MRI)and follow-up computed tomography(CT) or MRI. The ADC values(ADC_(10), ADC_(30_, ADC_(median) and ADC_(max))were obtained from the histogram's 10 th, 30 th, 50 th and 100 th percentiles. The ratios of ADC_(10), ADC_(30_,ADCmedian and ADCmax to the mean non-lesion area-ADC(RADC_(10), RADC_(30_, RADC_(median), and RADC_(max)) were calculated. The two patient groups were compared. Key predictive factors for survival were determined using the univariate and multivariate analysis of the Cox model. The Kaplan-Meier survival analysis was performed, and pairs of survival curves based on the key factors were compared using the log-rank test.Results: The ADC_(30_, ADCmedian, ADCmax, RADC_(30_, RADC_(median), and RADC_(max) were significantly larger in the progressive group than in the stable group(P<0.05). The median progression-free survival(PFS) was 22.9 months for all patients. The mean PFS for the stable and progressive groups were 47.7±1.3 and 9.8±1.3 months,respectively. Univariate analysis indicated that RADC_(10), RADC_(30_, and RADC_(median) were significantly correlated with the PFS [hazard ratio(HR)=31.02, 43.84, and 44.29, respectively, P<0.05 for all]. Multivariate analysis showed that RADCmedian was the only independent predictor of tumor progression(P=0.04). And the cutoff value of RADC_(median) was 0.71.Conclusions: Pre-RFA ADC histogram analysis might serve as a useful biomarker for predicting tumor progression and survival in patients with HCC treated with RFA.

关键词： Diffusion-weighted imaging apparent diffusion coefficient histogram analysis hepatocellular carcinoma radiofrequency ablation survival time

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

Heterostructure design of MOFs derived Co_(9)S_(8)/FeCoS_(2)/C composite with efficient microwave absorption and waterproof functions

引用

Journal of Materials Science & Technology 2022年第34期129卷 15-26页

作者： Runrun Cheng Yan Wang Xiaochuang Di zhao Lu Ping Wang xinming Wu School of Materials and Chemical Engineering Xi’an Technological UniversityXi’an 710021China

At present, the problem of electromagnetic wave(EMW) pollution is critical, and the design of highperformance absorbers is of great significance. Based on the synergy between dielectric and magnetic losses, and between multicomponents in heterostructures, the development of light-weight absorbers with a strong absorption capability and multiple scattering is a promising strategy to achieve highperformance absorbers. In this work, CoFe-MOF precursors with a bouquet-like structure were prepared via the hydrothermal method, and Co_(7)Fe_(3)/C and Co_(9)S_(8)/FeCoS_(2)/C composites were obtained through a carbonization and sulfuration treatment during the high-temperature pyrolysis process, respectively. The experimental and theoretical results show that the Co_(9)S_(8)/FeCoS_(2)/C composite has a better EMW absorption performance, and its optimal reflection loss(RL) value is-53.9 d B at a low filler loading of 20 wt.%,which is due to the S doping that enhances the interface polarization relaxation process and improves the impedance matching characteristics. Moreover, the Co_(9)S_(8)/FeCoS_(2)/C composite can be as candidates of high-efficiency absorbers in extreme application environments.

关键词： Electromagnetic absorption Metal-organic frameworks(MOFs) Bouquet-like CoFe-MOF Sulfur doping

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

Quantitative Method of the Structural Damage Identification of Gas Explosion Based on Case Study:The Shanxi “11. 23” Explosion Investigation

引用

Journal of Beijing Institute of Technology 2018年第1期27卷 1-14页

作者： Huanjuan zhao Yiran Yan xinming Qian Mine Emergency Technology Research Center(University of Science and Technology Beijing) State Administration of Production Safety Supervision and AdministrationSchool of Civil and Resources EngineeringUniversity of Science and Technology Beijing State Key Laboratory of High-Efficient Mining and Safety of Metal Mines (University of Science and Technology Beijing) Ministry of Education State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology

In order to present a retrospective analysis of exposition accidents using input data from investigation processes,data from a specific accident was examined,in which we analyzed possible involved gas species（ liquefied petroleum gas; nature gas） and computed their concentrations and distributions based on the interactions between the structures and the effects of the explosion. In this study,5 scenarios were created to analyze the impact effect. Moreover,a coupling algorithm was put into practice,with a practical outflow boundary and joint strength are applied. Finally,the damage effects of each scenario were simulated. Our experimental results showed significant differences in the 5 scenarios concerning the damage effects on the building structures. The results from scenario 3 agree with the accident characteristics,demonstrating the effectiveness of our proposed modeling method. Our proposed method reflects gas properties,species and the concentration and distribution,and the simulated results validates the root cause,process,and consequences of accidental explosions. Furthermore,this method describes the evolution process of explosions in different building structures. Significantly,our model demonstrates the quantatative explosion effect of factors like gas species,gas volumes,and distributions of gases on explosion results. In this study,a feasible,effective,and quantitative method for structure safety is defined,which is helpful to accelerate the development of safer site regulations.

关键词： mechanics of explosion simulation dynamic response liquefied petroleum gas nature gas quantitative analysis

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

Preparing a wettability-controllable stainless-steel mesh and its oil-water separation performance

引用

ChemPhysMater 2022年第2期1卷 126-132页

作者： Bohao Qi Wenjing Yi Changsong Liu Xinsheng zhao xinming Li School of Mechanical Engineering Qingdao University of TechnologyQingdao 266520China

The ability to regulate and apply surface wettability has attracted much attention in the surface engineering field.In this study,a simple chemical etching method was used to construct a rough micro/nano structure on 304 stainless steel mesh;this rough surface was subsequently decorated with fatty acids of varying chain length to regulate wettability.The wettability,composition,and morphology of the surface were characterized and ana-lyzed by measuring contact angles,and by atomic force microscopy,scanning electron microscopy,and Fourier-transform infrared spectroscopy.The superhydrophobic and superoleophilic properties of the mesh modified with long-chain fatty acids were examined for oil-water separation performance and reusability.The surface had a micro/nano hierarchical morphology with ordered carbon chains,and the hydrophilic-to-superhydrophobic transformation was achieved by adjusting the chain length of the fatty acid to deliver contact angles in the range of 30°~154°.The oil contact angle was always 0°,irrespective of the chain length fatty acid,and oil drops quickly penetrated the mesh surface.A fatty acid with a longer chain afforded a more hydrophobic and oleophilic mesh surface and better oil-water separation efficiency(up to 96%),which still exceeded 85%after 50 cycles of oil-water separation testing.Consequently,the prepared surface with controllable wettability has excellent prospects for use in intelligent response interfaces and oil-water separation applications.

关键词： Manipulating wettability Oil–water separation Stainless-steel mesh Chemical etching Fatty acids

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

Multi-omics fusion analysis models with machine learning predict survival of HER2-negative metastatic breast cancer: a multicenter prospective observational study

引用

Chinese Medical Journal 2023年第7期136卷 863-865页

作者： Jiani Wang Yuwei Liu Renzhi Zhang Zhenyu Liu Zongbi Yi Xiuwen Guan Xinming Zhao Jingying Jiang Jie Tian Fei Ma Department of Medical Oncology National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China Key Laboratory of Molecular Imaging Beijing Key Laboratory of Molecular ImagingInstitute of AutomationChinese Academy of SciencesBeijing 100190China School of Engineering Medicine Beihang UniversityBeijing 100191China Department of Diagnostic Radiology National Cancer Center/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100080China

To the Editor:Oncology precision medicine aims to identify patientsmostlikely torespondeffectivelytotherapies.Efforts to establish a survival prediction model using a single platform have not yet met the precision med... 详细信息

关键词： breast HER2 prospective

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

Evaluation of CT findings for the differentiation of benign from malignant primary retroperitoneal tumors

引用

Chinese Medical Journal 2014年第1期127卷 114-119页

作者： Zhu Zheng zhao Xinming Zhao Yanfeng Yang Lei zhao Jing Dai Jingrui Zhou Chunwu Department of Imaging Diagnosis Cancer Institute & HospitalChinese Academy of Medical Sciences & Peking Union MedicalCollege Beijing 100021 China

Background Benign and malignant primary retroperitoneal tumors （RT） have different pathological manifestations,and overlapping imaging characteristics.This study aimed to evaluate the value of computed tomography （CT） for differentiating benign from malignant RT.Methods One hundred and ninety-four patients with clinical and radiographic data were evaluated retrospectively following surgical resection of primary RT.There were 38.1％（n=74） benign lesions and 61.9％（n=120） malignant lesions.Categorical variables were tested with a chi-square test or Fisher＇s exact test for the diagnostic indexes and sensitivity and specificity of CT characteristics.Results In univariate analysis,the differences in ill-defined margins,irregular surfaces,long diameter ＞6.75 cm,short diameter ＞6.25 cm,and solid or mixed texture had statistical significance; the sensitivity and specificity were 44.2％ and 91.9％,70.0％ and 62.2％,68.8％ and 60.7％,59.7％ and 74.2％,87.5％ and 35.1％,respectively.In multivariate analysis,a combination of all the above indexes was the best model for differentiating malignant tumors,resulting in the most accurate diagnosis of malignancies with a sensitivity of 77.2％ and a specificity of 81.1％（P＜0.0001） when the score was 4.The differences in other findings including CT attenuation,number,and calcification had no statistical significance.The unique characteristics included the spotted enhancement （mottled high density）in schwannoma （P＜0.0001）,adipose tissue in liposarcoma （P＜0.0001）and paravertebral location in neurogenic tumors （P＜0.0001）.Conclusions More accurate differential diagnosis of primary RT can be made through comprehensive analysis of the combined diagnostic indexes of CT.Some specific characteristics of CT can assist in preoperative planning.

关键词： retroperitoneal tumor computed tomography X-ray

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

SAR Change Detection Algorithm Combined with FFDNet Spatial Denoising

引用

Journal of Environmental & Earth Sciences 2023年第2期5卷 88-101页

作者： Yuqing Wu Qing Xu Zheng Zhang Jingzhen Ma Tianming zhao xinming Zhu Institute of Geospatial Information Information Engineering UniversityZhengzhouHenan450001China

Objectives:When detecting changes in synthetic aperture radar(SAR)images,the quality of the difference map has an important impact on the detection results,and the speckle noise in the image interferes with the extraction of change information.In order to improve the detection accuracy of SAR image change detection and improve the quality of the difference map,this paper proposes a method that combines the popular deep neural network with the clustering algorithm.Methods:Firstly,the SAR image with speckle noise was constructed,and the FFDNet architecture was used to retrain the SAR image,and the network parameters with better effect on speckle noise suppression were obtained.Then the log ratio operator is generated by using the reconstructed image output from the network.Finally,K-means and FCM clustering algorithms are used to analyze the difference images,and the binary map of change detection results is generated.Results:The experimental results have high detection accuracy on Bern and Sulzberger’s real data,which proves the effectiveness of the method.

关键词： SAR change detection Image noise reduction FFDNet Difference diagram Clustering algorithm

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

Seasonal Variation and Land-Use/Land-Cover Type Impacts on the Correlation of Urban Heat Island Intensity and Difference Vegetation Index with Satellite Data in Xi’an,China

引用

Wuhan University Journal of Natural Sciences 2018年第5期23卷 387-395页

作者： zhao Wenting ZHU xinming JIANG Guangxin GAO Zhiyuan College of Urban and Environment Northwest University

Green coverage has pronounced influences on urban heat island（UHI） effect, while the impacts of seasonal variation and Land-Use/Land-Cover（LULC） types on this effect has not been implemented. This paper investigated the spatio-seasonal characteristics of urban thermal environment and the vegetation-soil mixed area, and then explored the effects of vegetation status on UHI intensity from the perspectives of seasons and regions in Xi＇an using four Landsat 8 images. UHI intensity index was implemented to extract UHI intensity based on thermal infrared imagery, and difference vegetation index（DVI） was used to represent vegetation-soil mixed area. Results indicated that DVI has impacts on UHI intensity, and their relations vary with season and region. In the whole Xi＇an, if UHI intensity is smaller than-0.1, DVI increases with the increase of UHI intensity; whereas for UHI intensity is greater than-0.1, DVI decreases with increases of the UHI intensity from early spring to autumn. The highest correlation level was discovered in the autumn map（R^2=0.713）. Results of correlation analysis further displayed that DVI positively correlated with UHI intensity at impervious surface, and that the main urban area possessed the best correlation with R^2=0.564 5.

关键词： urban heat island （UHI） difference vegetation index（DVI） spatial and seasonal variation correlation analysis Xi＇an

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

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：