检索结果-南通市图书馆

Efficient reduction and adsorption of Cr(Ⅵ)using FeCl_(3)-modified biochar:Synergistic roles of persistent free radicals and Fe(Ⅱ)

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 2024年第3期137卷 626-638页

作者： Shujie Hu Chengshuai Liu Hongling Bu Manjia Chen ying-heng fei National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and ManagementInstitute of Eco-environmental and Soil SciencesGuangdong Academy of SciencesGuangzhou 510650China State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of ScienceGuiyang 550081China School of Environment Science and Engineering Guangzhou UniversityGuangzhou 510006China College of Resources and Environment Chongqing SchoolUniversity of Chinese Academy of SciencesChongqing 400714China School of Environmental Science and Engineering Guangdong University of TechnologyGuangzhou 510006China

Transition metal iron and persistent free radicals(PFRs)both affect the redox properties of biochar,but the electron transfer relationship between them and the coupling reduction mechanism of Cr(Ⅵ)requires further *** untangle the interplay between iron and PFRs in biochar and the infuences on redox properties,FeCl_(3)-modified rice husk biochar(FBCs)was prepared and its reduction mechanism for Cr(Ⅵ)without light was *** FBCs had higher surface positive charges,oxygen-containing functional groups,and PFRs compared with pristine rice husk biochar(BC).Phenoxyl PFRs with high electrondonating capability formed in *** pronounced electron paramagnetic resonance signals showed that the PFRs preferred to form at lower Fe(Ⅲ)*** a high concentration of Fe(Ⅲ)would be reduced to Fe(Ⅱ)and consumed the formed *** kinetics and X-ray photoelectron spectroscopy analy.is indicated that the FBCs effectively.enhanced the Cr(Ⅵ)removal efficiency by 1.54-8.20 fold and the Cr(Ⅵ)reduction efficiency by 1.88-9.29 fold compared to those of *** quenching and competitive reductant addition experiments revealed that the higher Cr(Ⅵ)reduction performance of FBCs was mainly.attributed to the formed PFRs,which could contribute to~74.0%of Cr(Ⅵ)reduction by direct or indirect electron *** PFRs on FBCs surfaces could promote the Fe(Ⅲ)/Fe(Ⅱ)cycle through single electron transfer and synergistically.accelerate~52.3%of Cr(Ⅵ)*** study provides an improved understanding of the reduction mechanism of iron-modified biochar PFRs on Cr(Ⅵ)in environments.

关键词： Biochar Iron-modification Cr(Ⅵ) Electron transfer Reduction mechanism

Three-dimensional numerical manifold method for heat conduction problems with a simplex integral on the boundary

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2024年第4期67卷 1007-1022页

作者： TONG DeFu yI XiongWei TAN fei JIAO yuyong LIANG JiaWei Faculty of Engineering China University of GeoscienceWuhan 430074China Department of Civil Engineering Monash UniversityMelbourne VIC 3800Australia Badong National Observation and Research Station of Geohazards China University of GeoscienceWuhan 430074China

The three-dimensional numerical manifold method(3D-NMM),which is based on the derivation of Galerkin's variation,is a powerful calculation tool that uses two cover *** 3D-NMM can be used to handle continue-discontinue problems and extend to THM *** this study,we extended the 3D-NMM to simulate both steady-state and transient heat conduction *** modelling was carried out using the raster methods(RSM).For the system equation,a variational method was employed to drive the discrete equations,and the crucial boundary conditions were solved using the penalty *** solve the boundary integral problem,the face integral of scalar fields and two-dimensional simplex integration were used to accurately.describe the integral on poly.onal *** numerical examples were used to verify the results of 3D steady-state and transient heat-conduction *** numerical results indicated that the 3D-NMM is effective for handling 3D both steadystate and transient heat conduction problems with high solution accuracy.

关键词： three-dimensional numerical manifold method transient analy.is heat conduction problem Galerkin variation simplex integration

Point Cloud Classification Using Content-Based Transformer via Clustering in Feature Space

在线全文

学校读者我要写书评

暂无评论

IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 231-239页

作者： yahui Liu Bin Tian yisheng Lv Lingxi Li fei-yue Wang the State Key Laboratory for Management and Control of Complex Systems Institute of AutomationChinese Academy of SciencesBeijing 100190 the School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100190 IEEE the Transportation and Autonomous Systems Institute(TASI)and the Department of Electrical and Computer Engineering Purdue School of Engineering and TechnologyIndiana University-Purdue University Indianapolis(IUPUI)Indianapolis 46202 USA

Recently. there have been some attempts of Transformer in 3D point cloud classification. In order to reduce computations, most existing methods focus on local spatial attention,but ignore their content and fail to establish relationships between distant but relevant points. To overcome the limitation of local spatial attention, we propose a point content-based Transformer architecture, called PointConT for short. It exploits the locality of points in the feature space(content-based), which clusters the sampled points with similar features into the same class and computes the self-attention within each class, thus enabling an effective trade-off between capturing long-range dependencies and computational complexity. We further introduce an inception feature aggregator for point cloud classification, which uses parallel structures to aggregate high-frequency and low-frequency information in each branch separately. Extensive experiments show that our PointConT model achieves a remarkable performance on point cloud shape classification. Especially. our method exhibits 90.3% Top-1 accuracy on the hardest setting of ScanObjectN N. Source code of this paper is available at https://***/yahuiliu99/PointC onT.

关键词： Content-based Transformer deep learning feature aggregator local attention point cloud classification

Strength and ductility optimization of HPDC AlSi8MgCuZn2 alloys by modifying pre-aging treatment

在线全文

学校读者我要写书评

暂无评论

China Foundry 2024年第4期21卷 343-351页

作者： yuan-hang Jiang Hui-ting Zheng fei Liu Hai-dong Zhao National Engineering Research Center of Near-net Shape Forming for Metallic Materials South China University of TechnologyGuangzhou 510641China

Considering the components produced by high pressure die casting(HPDC)process usually.with ultra-large sizes and complex morphologies,high temperature solid solution treatment is not a suitable method to further improve their mechanical *** this study,two-stage aging treatment with different pre-aging times was designed and employed to further improve the mechanical properties of HPDC Al8SiMgCuZn *** characteristics of precipitates were evaluated by a transmission electron microscope(TEM),and the precipitation strengthening mechanism was *** results reveal that the strengthening is mainly.contributed by the precipitation ofβ″phase after two-stage aging,and the number density and size of the precipitates are significantly.depended on the pre-aging *** number density of precipitates is increased with the pre-aging time prolonged from 0 h to 4 h,and then decreases with the further increase of pre-aging time from 4 h to 6 *** precipitates with the highest density and smallest size are observed after pre-aging for 4 *** pre-aged at 100℃for 4 h and then artificial aged at 200℃for 30 min,the yield strength of 207 MPa,ultimate tensile strength of 325 MPa and elongation of 7.6%are achieved.

关键词： high pressure die cast aluminum alloy microstructural heterogeneity mechanical properties precipitation strengthening two-stage aging

Rosemary extract improves egg quality by altering gut barrier function,intestinal microbiota and oviductal gene expressions in late-phase laying hens

在线全文

学校读者我要写书评

暂无评论

Journal of Animal Science and Biotechnology 2024年第1期15卷 295-312页

作者： Lianhua Zhang Junwei Ge fei Gao Min yang Hui Li fei Xia Hongtong Bai Xiangshu Piao Zhiying Sun Lei Shi Key Laboratory of Plant Resources Institute of BotanyChinese Academy of SciencesBeijing 100093China China National Botanical Garden Beijing 100093China College of Pharmacy Shandong University of Traditional Chinese MedicineJinan 250355China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Animal Nutrition College of Animal Science and TechnologyChina Agricultural UniversityBeijing 100193China

Background Rosemary extract(RE)has been reported to exert antioxidant ***,the application of RE in late-phase laying hens on egg quality,intestinal barrier and microbiota,and oviductal function has not been systematically.*** study was investigated to detect the potential effects of RE on performance,egg quality,serum parameters,intestinal heath,cecal microbiota and metabolism,and oviductal gene expressions in late-phase laying hens.A total of 21065-week-old“Jing Tint 6”laying hens were randomly.allocated into five treatments with six replicates and seven birds per replicate and fed basal diet(CON)or basal diet supplemented with chlortetracycline at 50 mg/kg(CTC)or RE at 50 mg/kg(RE50),100 mg/kg(RE100),and 200 mg/kg(RE200).Results Our results showed that RE200 improved(Pyolk,serum superoxide dismutase(SOD)compared with *** significant differences were observed for Haugh unit and n-6/n-3 of egg yolk among CTC,RE50,RE100 and RE200 *** with CTC and RE50 groups,RE200 increased serum SOD activity on d 28 and *** with CON,RE supplementation decreased(Py RE 200,including Firmicutes,Eisenbergiella,Paraprevotella,Papillibacter,and butyrate,were closely.associated with Haugh unit,n-6/n-3,SOD,IL-6,and ***2 analy.is indicated that RE altered carbohydrate and amino acid metabolism of cecal microbiota and increased butyrate synthesizing enzymes,including 3-oxoacid Co A-transferase and butyrate-acetoacetate Co ***,transcriptomic analy.is revealed that RE200 improved gene expressions and functional pathways related to immunity and albumen formation in the oviductal *** Dietary supplementation with 2

关键词： Intestinal health Laying hens Microbiota Oviductal function Phytochemicals Production

Comparison of Rotating Stall Warning by Different Methods for Variable Speed Configurations in a Contra-Rotating Compressor

在线全文

学校读者我要写书评

暂无评论

Journal of Thermal Science 2024年第4期33卷 1379-1393页

作者： XUE fei WANG yan'gang LIU Qian WU Tong LIU Hanru School of Power and Energy Northwestern Polytechnical UniversityXi’an710072China

Stall in compressors can cause performance degradation and even lead to *** unacceptable consequences can be avoided by timely.monitoring stall inception and taking effective *** paper focused on the rotating stall warning in a low-speed axial contra-rotating ***,the stall disturbance characteristics under different speed configurations were *** results showed that as the speed ratio(RR)increased,the stall disturbance propagation speed based on the rear rotor speed gradually.***,the standard deviation(SD)method,the cross-correlation(CC)method,and the discrete wavelet transform(DWT)method were employed to obtain the stall initiation moments of three different speed *** was found that the SD and CC methods did not achieve significant stall warning results in all three speed ***,the stall initiation moment obtained by the DWT method at RR=1.125 was one period after the stall had fully.developed,which was ***,a stall warning method was developed in the present work based on the long short-term memory(LSTM)regression *** apply.ng the LSTM model,the predicted stall initiation moments of three speed configurations were at the 557th,518th,and 333rd revolution,which were44,2,and 74 revolutions ahead of stall onset moments,***,in scenarios where a minor disturbance preceded the stall,the stall warning effect of the LSTM was greatly.improved in comparison with the aforementioned three *** contrast,when the pressure fluctuation before the stall was relatively.small,the differences between the stall initiation moments predicted by these four methods were not significant.

关键词： contra-rotating compressor stall disturbance stall initiation moment long short-term memory(LSTM) stall warning

Hydroly.is mechanism of ybB_(2)C_(2)and the microstructure of the carbon derived from the hydroly.is reaction

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2024年第4期171卷 209-221页

作者： Zhihui Li Hao Zhang Jixin Chen Jiemin Wang Xiaohui Wang Jinxing yang Chao Zhang Zerong Zhang Hongyang Liu fei Huang Meishuan Li fei Li Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Shanghai Key Laboratory for High Temperature Materials and Precision Forming School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China

Carbide-derived carbon(CDC)materials have gained great attention due to the excellent properties for various potential ***,graphite crystal is formed during a room-temperature hydroly.is pro-cess of layered compound ybB_(2)C_(2).The formation mechanism can be demonstrated by a ybB_(2)C_(2)molecular cell:yb^(3+)acts as a cathode where H_(2)O molecule is reduced to H atom and OH^(−)ion,while(B_(2)C_(2))^(3−)acts as an anode where OH−ion is oxidized to O ***,ybB_(2)C_(2)molecular cell begins to disintegrate,i.e.,yb^(3+)ion,B and C atoms dissociate from the molecular *** as-produced C atoms combine to form graphite *** initial graphite crystal is a cabbage-like microsphere,and then it gradually.disintegrates and transforms into layered *** addition,ybB_(6),yb_(3)(OH)_(3)n(BO_(3))_((3-n))sol,hydrogen,hydrocarbons,and carbon oxides form *** method provides a general and inexpensive route to obtain carbide-derived graphite crystal.

关键词： Carbide-derived carbon ybB_(2)C_(2) Hydroly.is Molecular cell First-principles calculations

Does City Shape Affect China's Economic Development?

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

China & World Economy 2024年第1期32卷 21-56页

作者： Wei Zou fei yang Economics and Management School Wuhan UniversityChina

This paper constructs a general equilibrium spatial urban model and measures city geometric compactness using the patch-shape index based on evidence from satellite imagery and basic vector maps of *** adopts the ordinary least squares and instrumental variable approaches to examine the effect of city shape on the urban development of 279 Chinese cities at or above the prefecture *** empirical results show that there was a significant negative correlation between city shape and economic ***,every 1 percentage point increase in the patch-shape index led to a decrease in city-scale GDP by 0.009 percent,housing prices by 0.044 percent,and wages by 0.024 *** compact urban layouts attracted an inflow of households and firms,stimulated city economic growth,and were associated with increased housing prices and wage *** paper considers the cities'initial conditions,trends in population changes(expanding,shrinking,and stagnant cities),and geographic factors,and finds that the results are *** array of policy implications can be drawn from the research.

关键词： city footprint compactness economic development urban spatial shape

Construction of a nomogram model to predict technical difficulty in performing laparoscopic sphincter-preserving radical resection for rectal cancer

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2024年第18期30卷 2418-2439页

作者： Xiao-Cong Zhou Shi-Wei Guan fei-yue Ke Gaurav Dhamija Qiang Wang Bang-fei Chen Medical University(Wenzhou Central Hospital) Wenzhou 325000Zhejiang ProvinceChina Department of Hepatobiliary Surgery The Dingli Clinical Institute of Wenzhou Medical University(Wenzhou Central Hospital)Wenzhou 325000Zhejiang ProvinceChina Postgraduate Training Base Alliance of Wenzhou Medical University Wenzhou Central HospitalWenzhou 325000Zhejiang ProvinceChina School of International Studies Wenzhou Medical UniversityWenzhou Central HospitalWenzhou 325000Zhejiang ProvinceChina Department of Radiology The Dingli Clinical Institute of Wenzhou Medical University(Wenzhou Central Hospital)Wenzhou 325000Zhejiang ProvinceChina Department of Colorectal Surgery The Affiliated Zhejiang HospitalZhejiang University School of Medicine(Zhejiang Hospital)Hangzhou 310000Zhejiang ProvinceChina

BACKGROUND Colorectal surgeons are well aware that performing surgery for rectal cancer becomes more challenging in obese patients with narrow and deep pelvic ***,it is essential for colorectal surgeons to have a comprehensive understanding of pelvic structure prior to surgery and anticipate potential surgical *** To evaluate predictive parameters for technical challenges encountered during laparoscopic radical sphincter-preserving surgery for rectal *** We retrospectively.gathered data from 162 consecutive patients who underwent laparoscopic radical sphincterpreserving surgery for rectal ***-dimensional reconstruction of pelvic bone and soft tissue parameters was conducted using computed tomography(CT)*** difficulty was categorized as either high or low,and multivariate logistic regression analy.is was employed to identify predictors of operative difficulty,ultimately.creating a *** Out of 162 patients,21(13.0%)were classified in the high surgical difficulty group,while 141(87.0%)were in the low surgical difficulty *** logistic regression analy.is showed that the surgical approach using laparoscopic intersphincteric dissection,intraoperative preventive ostomy,and the sacrococcygeal distance were independent risk factors for highly.difficult laparoscopic radical sphincter-sparing surgery for rectal cancer(Ply.the anterior-posterior diameter of pelvic inlet/sacrococcygeal distance was identified as a protective factor(Ply.constructed,demonstrating good predictive accuracy(C-index=0.834).CONCLUSION The surgical approach,intraoperative preventive ostomy,the sacrococcygeal distance,and the anterior-posterior diameter of pelvic inlet/sacrococcygeal distance could help to predict the difficulty of laparoscopic radical sphincter-preserving surgery.

关键词： Nomogram Rectal cancer Laparoscopic operation Sphincter-preserving surgery Technical difficulty