检索结果-南通市图书馆

Fabrication of AZ31/Mg3Y Composites with Excellent Strength and Plasticity via Accumulated Rolling Bonding and Diffusion Annealing

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2024年第2期37卷 339-352页

作者： Yang Feng Wenhuan Chen Zheng Xu Weijun He Bin Jiang Fusheng Pan College of Materials Science and Engineering Chongqing UniversityChongqing400044China International Joint Laboratory for Light Alloys(Ministry of Education) Chongqing UniversityChongqing400044China

AZ31/Mg3Y composites with a layer thickness of 100-200μm were fabricated by accumulated rolling bonding(ARB),which was followed by diffusion annealing at 300℃ for 0-32 h.An interface layer,containing numerous Al-Y precipitates,is formed in the Mg3Y layer that is adjacent to the interface as a result of Al diffusing from the AZ31 layers into the Mg3Y layers.The thickness of the interface layer gets increased and more precipitates are formed in the interface layer with the extension of the annealing time.The microhardness of the AZ31 and Mg3Y layer decreases firstly and then reaches a stable value,while the microhardness of the interface layer increases gradually with the extension of the annealing time.The AZ31/Mg3Y composites exhibit equivalent strength but increased ductility after diffusion annealing,in comparison to the as-rolled AZ31/Mg3Y composite.In addition,the AZ31/Mg3Y composites after annealing always present higher strength and ductility than AZ31/AZ31 composite,which was fabricated by the same process as that for the AZ31/Mg3Y composites.hetero-deformation induced strengthening also plays an important role in the excellent strength and ductility of the annealed AZ31/Mg3Y composite.This study can provide a direction for improving the plasticity and strength of magnesium alloys synergistically.

关键词： AZ31/Mg3Y composite Accumulated rolling bonding Diffusion annealing Precipitates Strengthening

Conservation of architectural paintings at Xiaonan Garden, former residence of Weng family in Changshu

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Architectural Research 2016年第1期5卷 91-100页

作者： Weijun He Shi Hu Lifang Ji Architecture Academy Southeast University Nanjing 210096 China Nanjing Museum Nanjing 210096 China

Xiaonan Garden is the back garden at the Weng family＇s former residence, a famed mansion in Jiangnan. Various architectural colored paintings in the Jiangnan style, including a rare paster colored painting, are preserved in the garden. This study examines the wooden support, pigments, and structure of the painting and conducts a series of conservation experiments in situ and in the laboratory. Several conservation problems, such as the manually brushed lime, re-adherence of flaking painting layers, and consolidation of gold foil, were solved, and good results were obtained. Virtual recovery provided a solid foundation for protection and example of research on architectural colored paintings in Jiangnan.

关键词： Architectural colored painting Conservation

Ensemble enhanced active learning mixture discriminant analysis model and its application for semi-supervised fault classification

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Information Technology & Electronic Engineering 2022年第12期23卷 1814-1827页

作者： weijun WANG Yun WANG Jun WANG Xinyun FANG Yuchen he Key Laboratory of Intelligent Manufacturing Quality Big Data Tracing and Analysis of Zhejiang Province China Jiliang UniversityHangzhou 310018China Mechanical and Electrical Engineering Department Zhejiang Tongji Vocational College of Science and TechnologyHangzhou 311231China Suzhou Institute of Metrology Suzhou 215004China

As an indispensable part of process monitoring, the performance of fault classification relies heavily on the sufficiency of process knowledge. However, data labels are always difficult to acquire because of the limited sampling condition or expensive laboratory analysis, which may lead to deterioration of classification performance.To handle this dilemma, a new semi-supervised fault classification strategy is performed in which enhanced active learning is employed to evaluate the value of each unlabeled sample with respect to a specific labeled dataset.Unlabeled samples with large values will serve as supplementary information for the training dataset. In addition,we introduce several reasonable indexes and criteria, and thus human labeling interference is greatly reduced. Finally,the fault classification effectiveness of the proposed method is evaluated using a numerical example and the Tennessee Eastman process.

关键词： Semi-supervised Active learning Ensemble learning Mixture discriminant analysis Fault classification

In-situ investigation on the microstructure evolution of Mg-2Gd alloys during the V-bending tests

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2022年第36期131卷 167-176页

作者： Chao he Jianxin Zhou Yan Yang Bin Jiang Ming Yuan Zhihua Dong Yanfu Chai Weijun He Guangsheng Huang Dingfei Zhang Fusheng Pan State Key Laboratory of Mechanical Transmissions College of Materials Science and EngineeringChongqing UniversitySha Zheng Street 174#Sha Ping Ba DistrictChongqing 400044China National Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing 400044China School of Mechanical and Electrical Engineering Shaoxing UniversityShaoxing 312000China School of Chemistry and Materials Science Hubei Engineering UniversityXiaogan 432000China

In this work,the in-situ observation of the microstructure in the Mg-2Gd(wt%)alloys during V-bending tests was operated.The microstructure and texture evolutions were characterized by the in-situ electron backscatter diffraction(EBSD),scanning electron microscopy(SEM)and the high-angle annular dark-field scanning transmission electron microscopy(HAADF-STEM)technique.The results revealed a unique microcracks nucleation mechanism in the Mg-Gd alloys compared with the traditional Mg alloy(AZ31 alloy).The microcrack was nucleated at the grain boundary for the Mg-2Gd alloy and in the intragranular for the AZ31 alloy during the bending process.This difference mode between the Mg-Gd and the AZ31 alloys was mainly attributed to the more random topology of the grain boundary network,the lower grain boundary cohesion and the enhanced hinder ability for the dislocations due to the segregated Gd atoms in the Mg-Gd alloy.Furthermore,the microcracks that had a large angleθwith the extruded direction(ED)in the Mg-Gd alloys were preferred nucleated since grain boundaries had the larger normal stress during the bending process.

关键词： Magnesium In-situ V-bending Microstructure Texture Microcracks

Growth performance,fatty acid composition,and lipid metabolism are altered in groupers(Epinephelus coioides)by dietary fish oil replacement with palm oil

在线全文

学校读者我要写书评

暂无评论

Animal Nutrition 2022年第1期8卷 102-113页

作者： Yingmei Qin Lingyun he Yanfei Wang Dong Li weijun Chen Jidan Ye Xiamen Key Laboratory for Feed Quality Testing and Safety Evaluation Fisheries College of Jimei UniversityXiamen 361021China

In this study,we conducted a 56-d feeding trial to investigate the effects of replacing the fish oil(FO)with palm oil(PO)on the performance,tissue fatty acid(FA)composition,and mRNA levels of genes related to hepatic lipid metabolism in grouper(Epinephelus coioides).Five isolipidic(13%crude lipid)and isonitrogenous(48%CP)diets were formulated by incrementally adding PO to the control diet(25%fish meal and 9%added FO)to replace FO in the control diets.Triplicate groups of 30 groupers(initial weight:12.6±0.1 g)were fed one of the diets twice daily,to apparent satiety.The replacement of FO with 50%PO revealed maximum growth without affecting the performance and whole-body proximate compositions,and replacing FO with 100%PO revealed a comparable(P>0.05)growth with that of the control diet,suggesting PO as a suitable alternative to FO.The analysis of FA profiles in the dorsal muscle and liver though reflected the FA profile of the diet,PO substitutions above 50%could compromise(Phe FA profile in the liver and flesh of the fish species in comparison with the control diet.Furthermore,the mRNA levels of FAS,G6PD,LPL,PPARА,and D6FAD genes in the liver had positive linear and/or quadratic responses,but the SCD,HSL,ATGL,FABP,SREBP-1C and ELOVL5 had the opposite trend,with increasing dietary PO inclusion levels,whereas the mRNA level of ACC was not affected by dietary treatments.The optimal level of PO substitution for FO was estimated to be 47.1%of the feed,based on the regression analysis of percent weight gains against dietary PO inclusion levels;however,it might affect the FA profile in the liver and flesh of the fish species,and further study is required to investigate whether the changes in tissue FA composition will affect the welfare and market value over a production cycle of grouper.

关键词： Dietary lipid Epinephelus coioides Fatty acid metabolism Growth performance

Arsenic trioxide induced rhabdomyolysis, a rare but severe side effect, in an APL patient： a case report

在线全文

学校读者我要写书评

暂无评论

Frontiers of Medicine 2017年第2期11卷 284-286页

作者： Haiyan he Ran An Jian Hou weijun Fu Myeloma and Lymphoma Center Department of Hematology Changzheng Hospital Shanghai 200003 China

Arsenic trioxide （ATO）, a component of the traditional Chinese medicine arsenic sublimate, promotes apoptosis and induces leukemic cell differentiation. Combined with all-trans-retinotic acid （ATRA）, ATO has become the first-line induction therapy in treating acute promyelocytic leukemia （APL）. The most common side effects of ATO include hepatotoxicity, gastrointestinal symptoms, water-sodium retention, and nervous system damage. In this report, we present a rare side effect, rhabdomyolysis, in a 68-year-old female APL patient who was treated with ATO. After taking 10 mg ATO daily for 6 days, she presented shortness of breath, myodynia, elevated creatine kinase, and acute renal insufficiency. This report describes the first case of ATO-induced rhabdomyolysis.

关键词： arsenic trioxide APL rhabdomyolysis

Long-term declining in carbon monoxide(CO)at a rural site of Beijing during 2006-2018 implies the improved combustion efficiency and effective emission control

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2022年第5期34卷 432-442页

作者： Yingruo Li Zhiqiang Ma Tingting Han weijun Quan Junxia Wang Huaigang Zhou Di he Fan Dong Institute of Urban Meteorology China Meteorological AdministrationBeijing 100089China Key Laboratory of Atmospheric Chemistry China Meteorological AdministrationBeijing 100081China Environmental Meteorology Forecast Center of Beijing-Tianjin-hebei China Meteorological AdministrationBeijing 100089China College of Environmental Science and Engineering Peking UniversityBeijing 100871China

Carbon monoxide(CO)is primarily the result of incomplete combustion,which has impor-tant impacts on the atmospheric chemical cycle and climate.Improved quantitative char-acterization of long-term CO trends is important for both atmospheric modeling and the design and implementation of policies to efficiently control multiple pollutants.Due to the limitations of high time-resolution and high-quality long-term observational data,studies on long-term trends in the CO concentration in China are quite limited.In this study,the observational data of the concentration of CO in a rural site of Beijing during 2006-2018 was used to analyze the long-term trend in CO concentration in Beijing.The Theil-Sen method and the generalized additive model(GAM)-based method,were used to conduct the trend estimation analysis.We found that the concentration of CO at the Shangdianzi site showed a significant downward trend during 2006-2018,with a decline rate of 22.8±5.1 ppbV per year.The declining trend in CO also showed phasic characteristics,with a fast decreasing rate during the period of 2006-2008,stable variations during the period of 2009-2013 and a continuous downward trend after 2013.The declining trend in the CO concentration in the south to west(S-W)sectors where the polluted air masses come from is more rapid than that in the sectors where the clean air masses come from.The declining trend in the CO concentration implies the improved combustion efficiency and the successful air pollution control policies in Beijing and the surrounding area.

关键词： Carbon monoxide Long-term trend Theil-Sen method Generalized additive model (GAM)-based method Stratified analysis

Assessing artificial neural networks coupled with waveletanalysis for multi-layer soil moisture dynamics pr

在线全文

学校读者我要写书评

暂无评论

Research in Cold and Arid Regions 2016年第2期8卷 116-124页

作者： JunJun Yang ZhiBin he weijun Zhao Linze Inland River Basin Research Station Chinese EcoSystem Research Network Key Laboratory of Eco-hydrology of Inland River Basin Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Academy of Water Res

Soil moisture simulation and prediction in semi-arid regions are important for agricultural production, soil conservation and climate change. However, considerable heterogeneity in the spatial distribution of soil moisture, and poor ability of distributed hydrological models to estimate it, severely impact the use of soil moisture models in research and practical applications. In this study, a newly-developed technique of coupled (WA-ANN) wavelet analysis (W A) and artificial neural network (ANN) was applied for a multi-layer soil moisture simulation in the Pailugou catchment of the Qilian Mountains, Gansu Province, China. Datasets included seven meteorological factors: air and land surface temperatures, relative humidity, global radiation, atmospheric pressure, wind speed, precipitation, and soil water content at 20, 40, 60, 80, 120 and 160 cm. To investigate the effectiveness of W A-ANN, ANN was applied by itself to conduct a comparison. Three main findings of this study were: (1) ANN and WA-ANN provided a statistically reliable and robust prediction of soil moisture in both the root zone and deepest soil layer studied (NSE >0.85, NSE means Nash-Sutcliffe Efficiency coefficient); (2) when input meteorological factors were transformed using maximum signal to noise ratio (SNR) and one-dimensional auto de-noising algorithm (heursure) in W A, the coupling technique improved the performance of ANN especially for soil moisture at 160 cm depth; (3) the results of multi-layer soil moisture prediction indicated that there may be different sources of water at different soil layers, and this can be used as an indicator of the maximum impact depth of meteorological factors on the soil water content at this study site. We conclude that our results show that appropriate simulation methodology can provide optimal simulation with a minimum distortion of the raw-time series; the new method used here is applicable to soil sciences and management applications.

关键词： artificial neural network denoising wavelet analysis time series analysis soil moisture prediction

Enhancement of Fenton oxidation for removing organic matter from hypersaline solution by accelerating ferric system with hydroxylamine hydrochloride and benzoquinone

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2016年第3期28卷 16-23页

作者： Siwei Peng weijun Zhang Jie he Xiaofang Yang Dongsheng Wang Guisheng Zeng Key Laboratory of Jiangxi Province for Ecological Diagnosis-Remediation and Pollution Control Nanchang Hangkong University State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of Sciences

Fenton oxidation is generally inhibited in the presence of a high concentration of chloride ions.This study investigated the feasibility of using benzoquinone（BQ） and hydroxylamine hydrochloride（HA） as Fenton enhancers for the removal of glycerin from saline water under ambient temperature by accelerating the ferric system.It was found that organics removal was not obviously affected by chloride ions of low concentration（less than 0.1 mol/L）,while the mineralization rate was strongly inhibited in the presence of a large amount of chloride ions.In addition,ferric hydrolysis-precipitation was significantly alleviated in the presence of HA and BQ,and HA was more effective in reducing ferric ions into ferrous ions than HA,while the H_2O_2 decomposition rate was higher in the BQ-Fenton system.Electron spin resonance analysis revealed that OH production was reduced in high salinity conditions,while it was enhanced after the addition of HA and BQ（especially HA）.This study provided a possible solution to control and alleviate the inhibitory effect of chloride ions on the Fenton process for organics removal.

关键词： Saline solution Fenton oxidation Hydroxyl radicals Benzoquinone Hydroxylamine hydrochloride