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Experimental investigation on the permeability of gap-graded soil due to horizontal suffusion considering boundary effect
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作者 Xuwei Wang Yeshuang Xu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第3期1072-1084,共13页
The boundary condition is a crucial factor affecting the permeability variation due to suffusion.An experimental investigation on the permeability of gap-graded soil due to horizontal suffusion considering the boundar... The boundary condition is a crucial factor affecting the permeability variation due to suffusion.An experimental investigation on the permeability of gap-graded soil due to horizontal suffusion considering the boundary effect is conducted,where the hydraulic head difference(DH)varies,and the boundary includes non-loss and soil-loss conditions.Soil samples are filled into seven soil storerooms connected in turn.After evaluation,the variation in content of fine sand(ΔR_(f))and the hydraulic conductivity of soils in each storeroom(C_(i))are analyzed.In the non-loss test,the soil sample filling area is divided into runoff,transited,and accumulated areas according to the negative or positive ΔR_(f) values.ΔR_(f) increases from negative to positive along the seepage path,and Ci decreases from runoff area to transited area and then rebounds in accumulated area.In the soil-loss test,all soil sample filling areas belong to the runoff area,where the gentle-loss,strengthened-loss,and alleviated-loss parts are further divided.ΔR_(f) decreases from the gentle-loss part to the strengthened-loss part and then rebounds in the alleviated-loss part,and C_(i) increases and then decreases along the seepage path.The relationship between ΔR_(f) and Ci is different with the boundary condition.Ci exponentially decreases with ΔR_(f) in the non-loss test and increases with ΔR_(f) generally in the soil-loss test. 展开更多
关键词 Suffusion PERMEABILITY Experimental investigation Boundary effect Horizontal seepage
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Investigation of the epidemiology,pathogenicity and immunogenicity of Bordetella bronchiseptica isolated from cats and dogs in China from 2021 to 2023
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作者 Qinghua Shang Wenhui Gao +7 位作者 Xiangting Zhang Jianqing Zhao Ying Wu Haoqi Li Ming Zhou Zhen F.Fu Chengguang Zhang Ling Zhao 《Animal Diseases》 CAS 2024年第3期156-172,共17页
Bordetella bronchiseptica(Bb)is recognized as a leading cause of respiratory diseases in dogs and cats.However,epidemiological data on Bb in dogs and cats in China are still limited,and there is no commercially availa... Bordetella bronchiseptica(Bb)is recognized as a leading cause of respiratory diseases in dogs and cats.However,epidemiological data on Bb in dogs and cats in China are still limited,and there is no commercially available vaccine.Live vaccines containing Bb that are widely used abroad are generally efective but can establish latency and potentially reactivate to cause illness in some immunodefcient vaccinated recipients,raising safety concerns.In this study,34 canine-derived and two feline-derived Bb strains were isolated from 1809 canine and 113 feline nasopharyngeal swab samples collected from eight provinces in China from 2021 to 2023.The PCR results showed that the percentage of positive Bb was 22.94%(441/1922),and more than 90%of the Bb isolates had four virulence factor-encoding genes(VFGs),namely,fhaB,prn,betA and dnt.All the isolated strains displayed a multidrug-resistant phenotype.The virulence of 10 Bb strains isolated from dogs with respiratory symptoms was tested in mice,and we found that eight isolates were highly virulent.Furthermore,the eight Bb isolates with high virulence were inactivated and intramuscularly injected into mice,and three Bb strains(WH1218,WH1203 and WH1224)with the best protective efcacy were selected.Dogs immunized with these three strains exhibited strong protection against challenge with the Bb feld strain WH1218.Ultimately,the WH1218 strain with the greatest protection in dogs was selected as the vaccine candidate.Dogs and cats that received a vaccine containing 109 CFU of the inactivated WH1218 strain showed complete protection against challenge with the Bb feld strain WH1218.This study revealed that Bb is an important pathogen that causes respiratory diseases in domestic dogs and cats in China,and all the isolates exhibited multidrug resistance.The present work contributes to the current understanding of the prevalence,antimicrobial resistance,and virulence genes of Bb in domestic dogs and cats.Additionally,our results suggest that the WH1218 strain is a promising candidate safe and efcacious inactivated Bb vaccine. 展开更多
关键词 Bordetella bronchiseptica Epidemiological investigation PATHOGENICITY IMMUNOGENICITY Inactivated vaccine
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Experimental investigation on coal pore-fracture variation and fractal characteristics synergistically affected by solvents for improving clean gas extraction
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作者 Feilin Han Sheng Xue +3 位作者 Chunshan Zheng Zhongwei Chen Guofu Li Bingyou Jiang 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第3期413-425,共13页
Chemical solvents instead of pure water being as hydraulic fracturing fluid could effectively increase permeability and improve clean methane extraction efficiency.However,pore-fracture variation features of lean coal... Chemical solvents instead of pure water being as hydraulic fracturing fluid could effectively increase permeability and improve clean methane extraction efficiency.However,pore-fracture variation features of lean coal synergistically affected by solvents have not been fully understood.Ultrasonic testing,nuclear magnetic resonance analysis,liquid phase mass spectrometry was adopted to comprehensively analyze pore-fracture change characteristics of lean coal treated by combined solvent(NMP and CS_(2)).Meanwhile,quantitative characterization of above changing properties was conducted using geometric fractal theory.Relationship model between permeability,fractal dimension and porosity were established.Results indicate that the end face fractures of coal are well developed after CS2and combined solvent treatments,of which,end face box-counting fractal dimensions range from 1.1227 to 1.4767.Maximum decreases in ultrasonic longitudinal wave velocity of coal affected by NMP,CS_(2)and combined solvent are 2.700%,20.521%,22.454%,respectively.Solvent treatments could lead to increasing amount of both mesopores and macropores.Decrease ratio of fractal dimension Dsis 0.259%–2.159%,while permeability increases ratio of NMR ranges from 0.1904 to 6.4486.Meanwhile,combined solvent could dissolve coal polar and non-polar small molecules and expand flow space.Results could provide reference for solvent selection and parameter optimization of permeability-enhancement technology. 展开更多
关键词 Clean gas extraction Chemical solvent Experimental investigation Fractal characteristics Pore fracture
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Serological Investigation into the Infected Genotypes of Patients with Japanese Encephalitis in the Coastal Provinces of China
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作者 Weijia Zhang Jierong Zhao +10 位作者 Qikai Yin Shenghui Liu Ruichen Wang Shihong Fu Fan Li Ying He Kai Nie Guodong Liang Songtao Xu Guang Yang Huanyu Wang 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第7期716-725,共10页
Objective Genotypes(G)1,3,and 5 of the Japanese encephalitis virus(JEV)have been isolated in China,but the dominant genotype circulating in Chinese coastal areas remains unknown.We searched for G5 JEV-infected cases a... Objective Genotypes(G)1,3,and 5 of the Japanese encephalitis virus(JEV)have been isolated in China,but the dominant genotype circulating in Chinese coastal areas remains unknown.We searched for G5 JEV-infected cases and attempted to elucidate which JEV genotype was most closely related to human Japanese encephalitis(JE)in the coastal provinces of China.Methods In this study,we collected serum specimens from patients with JE in three coastal provinces of China(Guangdong,Zhejiang,and Shandong)from 2018 to 2020 and conducted JEV cross-neutralization tests against G1,G3,and G5.Results Acute serum specimens from clinically reported JE cases were obtained for laboratory confirmation from hospitals in Shandong(92 patients),Zhejiang(192 patients),and Guangdong(77 patients),China,from 2018 to 2020.Seventy of the 361 serum specimens were laboratory-confirmed to be infected with JEV.Two cases were confirmed to be infected with G1 JEV,32 with G3 JEV,and two with G5 JEV.Conclusion G3 was the primary infection genotype among JE cases with a definite infection genotype,and the infection caused by G5 JEV was confirmed serologically in China. 展开更多
关键词 Japanese encephalitis virus Serological investigation Plaque reduction neutralization test Cross-neutralization test GENOTYPE
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Systematic investigation of Radix Salviae for treating diabetic peripheral neuropathy disease based on network Pharmacology
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作者 Tao Kang Xiao Qin +1 位作者 Yan Chen Qian Yang 《World Journal of Diabetes》 SCIE 2024年第5期945-957,共13页
BACKGROUND Diabetic peripheral neuropathy(DPN)is a debilitating complication of diabetes mellitus with limited available treatment options.Radix Salviae,a traditional Chinese herb,has shown promise in treating DPN,but... BACKGROUND Diabetic peripheral neuropathy(DPN)is a debilitating complication of diabetes mellitus with limited available treatment options.Radix Salviae,a traditional Chinese herb,has shown promise in treating DPN,but its therapeutic mech-anisms have not been systematically investigated.AIM Radix Salviae(Danshen in pinin),a traditional Chinese medicine(TCM),is widely used to treat DPN in China.However,the mechanism through which Radix Salviae treats DPN remains unclear.Therefore,we aimed to explore the mechanism of action of Radix Salviae against DPN using network pharmacology.METHODS The active ingredients and target genes of Radix Salviae were screened using the TCM pharmacology database and analysis platform.The genes associated with DPN were obtained from the Gene Cards and OMIM databases,a drug-com-position-target-disease network was constructed,and a protein–protein inter-action network was subsequently constructed to screen the main targets.Gene Ontology(GO)functional annotation and pathway enrichment analysis were performed via the Kyoto Encyclopedia of Genes and Genomes(KEGG)using Bioconductor.RESULTS A total of 56 effective components,108 targets and 4581 DPN-related target genes of Radix Salviae were screened.Intervention with Radix Salviae for DPN mainly involved 81 target genes.The top 30 major targets were selected for enrichment analysis of GO and KEGG pathways.CONCLUSION These results suggested that Radix Salviae could treat DPN by regulating the AGE-RAGE signaling pathway and the PI3K-Akt signaling pathway.Therefore,Danshen may affect DPN by regulating inflammation and apoptosis. 展开更多
关键词 Diabetic peripheral neuropathy Radix Salviae Network pharmacology Systematic investigation
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A Survey of Crime Scene Investigation Image Retrieval Using Deep Learning
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作者 Ying Liu Aodong Zhou +1 位作者 Jize Xue Zhijie Xu 《Journal of Beijing Institute of Technology》 EI CAS 2024年第4期271-286,共16页
Crime scene investigation(CSI)image is key evidence carrier during criminal investiga-tion,in which CSI image retrieval can assist the public police to obtain criminal clues.Moreover,with the rapid development of deep... Crime scene investigation(CSI)image is key evidence carrier during criminal investiga-tion,in which CSI image retrieval can assist the public police to obtain criminal clues.Moreover,with the rapid development of deep learning,data-driven paradigm has become the mainstreammethod of CSI image feature extraction and representation,and in this process,datasets provideeffective support for CSI retrieval performance.However,there is a lack of systematic research onCSI image retrieval methods and datasets.Therefore,we present an overview of the existing worksabout one-class and multi-class CSI image retrieval based on deep learning.According to theresearch,based on their technical functionalities and implementation methods,CSI image retrievalis roughly classified into five categories:feature representation,metric learning,generative adversar-ial networks,autoencoder networks and attention networks.Furthermore,We analyzed the remain-ing challenges and discussed future work directions in this field. 展开更多
关键词 crime scene investigation(CSI)image image retrieval deep learning
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Auto-parametric resonance of a continuous-beam-bridge model under two-point periodic excitation:an experimental investigation and stability analysis
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作者 Li Yuchun Shen Chao +1 位作者 Liu Wei Li Dong 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第2期445-454,共10页
The auto-parametric resonance of a continuous-beam bridge model subjected to a two-point periodic excitation is experimentally and numerically investigated in this study.An auto-parametric resonance experiment of the ... The auto-parametric resonance of a continuous-beam bridge model subjected to a two-point periodic excitation is experimentally and numerically investigated in this study.An auto-parametric resonance experiment of the test model is conducted to observe and measure the auto-parametric resonance of a continuous beam under a two-point excitation on columns.The parametric vibration equation is established for the test model using the finite-element method.The auto-parametric resonance stability of the structure is analyzed by using Newmark's method and the energy-growth exponent method.The effects of the phase difference of the two-point excitation on the stability boundaries of auto-parametric resonance are studied for the test model.Compared with the experiment,the numerical instability predictions of auto-parametric resonance are consistent with the test phenomena,and the numerical stability boundaries of auto-parametric resonance agree with the experimental ones.For a continuous beam bridge,when the ratio of multipoint excitation frequency(applied to the columns)to natural frequency of the continuous girder is approximately equal to 2,the continuous beam may undergo a strong auto-parametric resonance.Combined with the present experiment and analysis,a hypothesis of Volgograd Bridge's serpentine vibration is discussed. 展开更多
关键词 auto-parametric resonance continuous beam bridge model two-point excitation experimental investigation stability analysis vibration of Volgograd Bridge
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Investigation and Analysis of Main Diseases of Landscape Plants in the Main Urban Area of Lu'an City
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作者 Gao LIU Hao SONG Juanjuan HU 《Plant Diseases and Pests》 2024年第1期18-21,共4页
To figure out the disease occurrence of landscape plants in the main urban area of Lu'an City,the author investigated the disease occurrence of landscape plants in park green space,residential green space,unit att... To figure out the disease occurrence of landscape plants in the main urban area of Lu'an City,the author investigated the disease occurrence of landscape plants in park green space,residential green space,unit attached green space and main road in the area under administration.The survey results showed that there were 29 species of urban landscape plant diseases,mainly powdery mildew and spot diseases.According to the characteristics of the diseases,the causes and problems of the diseases were analyzed,and the corresponding prevention and control measures were put forward. 展开更多
关键词 Landscape plant Disease species investigation Status analysis Lu'an City
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A Case of Investigation and Diagnosis of Immune Thrombocytopenic Purpura After Vaccination of COVID-19 Inactivated Vaccine
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作者 Hao Leng Ju Yan +3 位作者 Xiaoling Zhu Xiaoxia Jiang Jingzhi Li Yundan Cheng 《Journal of Clinical and Nursing Research》 2024年第6期328-334,共7页
Objective:Analyze the relationship between inoculating one case of the COVID-19 inactivated vaccine(Vero cell)and immune thrombocytopenic purpura to provide a reference for the standardized handling of adverse events ... Objective:Analyze the relationship between inoculating one case of the COVID-19 inactivated vaccine(Vero cell)and immune thrombocytopenic purpura to provide a reference for the standardized handling of adverse events following immunization.Methods:According to the"National Monitoring Program for Suspected Adverse Reactions to Vaccinations,"an on-site investigation,data collection and analysis,expert group diagnosis,and medical association assessment were conducted on a case of immune thrombocytopenic purpura in District A of Chongqing after vaccination with the inactivated COVID-19 vaccine.The assessment report was delivered to the three relevant parties,the case was reviewed,and the experience was summarized.Results:The investigation and diagnosis by the district-level vaccination abnormal reaction expert group concluded that the disease that occurred after vaccination with the COVID-19 inactivated vaccine was secondary immune thrombocytopenic purpura,an abnormal reaction to the vaccination.The medical damage was classified as Level II Grade B.The vaccine production enterprise raised objections to this conclusion.After re-assessment by the municipal-level medical association,the conclusion was consistent with that of the district-level medical association.The vaccine production enterprise did not raise any further objections.Conclusion:Through active collaboration among district and municipal-level medical associations,disease control institutions,and vaccination units,the recipients have been promptly and effectively treated,providing financial support for their subsequent treatment and safeguarding their rights.The investigation and disposal procedures for adverse events following immunization in Chongqing are clear,and the mechanism is sound.It is necessary to continue strengthening the monitoring of adverse events following immunization according to the existing plan and to ensure timely and standardized handling.Simultaneously,it is crucial to strengthen vaccine management and vaccination management. 展开更多
关键词 Adverse events following immunization IMMUNIZATIONS COVID-19 inactivated vaccine(Vero cell) Immune thrombocytopenic purpura investigation and diagnosis
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First contact investigations and compliance to treatment in patients with uveitis 被引量:1
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作者 Anuja Patil Sanjeev Gupta +5 位作者 Pradeep Venkatesh Mousumi Banerjee Vinod Kumar Rohan Chawla Shorya Vardhan Azad Atul Kumar 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第11期1820-1826,共7页
AIM:To ascertain the pattern of investigations at first contact in uveitic patients and evaluate compliance to treatment.METHODS:An observational study comprised of 201 uveitic patients presenting for the first time t... AIM:To ascertain the pattern of investigations at first contact in uveitic patients and evaluate compliance to treatment.METHODS:An observational study comprised of 201 uveitic patients presenting for the first time to our centre from January 2019 to June 2020.Detailed information regarding systemic investigations undertaken by specialists at the time of first contact and the cost of these investigations were reviewed on the first visit to our centre.Compliance with the treatment was determined and reasons behind non-compliance were evaluated on the first follow-up in patients who had no improvement in clinical signs and symptoms.RESULTS:The mean age of the study group was 35.35±14.1y and gender composition was 59.7%males and 40.3%females.Anterior uveitis was observed in 45.3%of patients,intermediate uveitis in 31.8%of patients,posterior uveitis in 14.9%of patients and panuveitis in 8.0%of patients.Association with a systemic disease was evident in 17.9%of patients.When compared with standard guidelines and uveitis patterns,systemic investigations were identified to be relevant only in 38.3%of patients.Non-compliance to treatment was documented in 22.4%of patients.Common reasons for non-compliance were inadequate counselling by the treating physician about treatment in 26.7%of patients and a busy schedule at work/school in 22.2%of patients.CONCLUSION:Significant number of investigations performed at first contact is found to be contrary to standard guidelines and are not contributory to the care.About a quarter of patients in this study are found to be non-compliant with the treatment.Compliance is more challenging to achieve in school-going children and working adults.The availability of comprehensive,periodically updated,evidence-based guidelines on the role of investigations and the use of trained counsellors may help to channelize proper evaluation and improve compliance to treatment,respectively,in patients with uveitis. 展开更多
关键词 UVEITIS COMPLIANCE investigationS first contact
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Modeling differential car-following behavior under normal and rainy conditions: A memory-based deep learning method with attention mechanism
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作者 柏海舰 过晨晨 +3 位作者 丁恒 卫立阳 孙婷 陈星宇 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第6期187-202,共16页
In order to analyze and learn the difference in car-following behavior between normal and rainy days, we first collect car-following trajectory data of an urban elevated road on normal and rainy days by microwave rada... In order to analyze and learn the difference in car-following behavior between normal and rainy days, we first collect car-following trajectory data of an urban elevated road on normal and rainy days by microwave radar and analyze the differences in speed, relative speed, acceleration, space headway, and time headway among data through statistics. Secondly, owing to the time-series characteristics of car-following data, we use the long short-term memory(LSTM) neural network optimized by attention mechanism(AM) and sparrow search algorithm(SSA) to learn the different car-following behaviors under different weather conditions and build corresponding models(ASL-Normal, ASL-Rain, where ASL stands for AM-SSA-LSTM), respectively. Finally, the simulation test shows that the mean square error(MSE) and reciprocal of time-to-collision(RTTC) of the ASL model are better than those of LSTM and intelligent diver model(IDM), which is closer to the real data. The ASL model can better learn different driving behaviors on normal and rainy days. However,it has a higher sensitivity to weather conditions from cross test on normal and rainy data-sets which need classification training or sample diversification processing. In the car-following platoon simulation, the stability performances of two models are excellent, which can describe the basic characteristics of traffic flow on normal and rainy days. Comparing with ASL-Rain model, the convergence time of ASL-Normal is shorter, reflecting that cautious driving behavior on rainy days will reduce traffic efficiency to a certain extent. However, ASL-Normal model produces a more severe and frequent traffic oscillation within a shorter period because of aggressive driving behavior on normal days. 展开更多
关键词 car-following behavior deep learning weather condition heterogeneous traffic flow
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Investigations on the tensile deformation of pure Mg and Mg–15Gd alloy by in-situ X-ray synchrotron radiation and visco-plastic self-consistent modeling
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作者 Yuling Xu Yuanding Huang +5 位作者 Yuye Wang Weiming Gan Shiwei Wang Emad Maawad Norbert Schell Norbert Hort 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第2期607-613,共7页
In this study,the texture evolutions of two Mg materials during tension are explored.In-situ X-ray synchrotron and Visco-Plastic SelfConsistent(VPSC) modeling are employed to investigate the different deformation mode... In this study,the texture evolutions of two Mg materials during tension are explored.In-situ X-ray synchrotron and Visco-Plastic SelfConsistent(VPSC) modeling are employed to investigate the different deformation modes between pure Mg and Mg-15Gd(wt.%) alloy.These two materials with a strong extrusion texture show large different slip/twinning activity behaviors during tensile deformation.The basal(a) slip has the highest contribution to the initial stage of plastic deformation for pure Mg.During the subsequent plastic deformation,the prismatic slip is dominant due to the strong ED//(100) fiber texture.In contrast,the deformation behavior of Mg-15Gd alloy is more complex.Twinning and basal slip are dominant at the early stage of plastic deformation,but further deformation results in the increased activation of prismatic and pyramidal slips.In comparison to pure Mg,the ratios of the critical resolved shear stress(CRSS) between non-basal slip and basal slip of the Mg-15Gd alloy are much lower. 展开更多
关键词 Mg alloy TEXTURE Mechanical behavior In-situ investigation
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Empirical Investigation of Treatment of Sour Gas by Novel Technology: Energy Optimization
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作者 Ehsan Monfared Farshad Farahbod 《American Journal of Analytical Chemistry》 CAS 2023年第4期175-183,共9页
The sour gas sweetening is one of the main processes in gas industries. Gas sweetening is done through chemical processes. Therefore, it requires high cost and energy. The results show that increasing the operating te... The sour gas sweetening is one of the main processes in gas industries. Gas sweetening is done through chemical processes. Therefore, it requires high cost and energy. The results show that increasing the operating temperature increases the mass transfer coefficient and increases the mass transfer rate. Theoretical and experimental data show that sulfur removal in 4.5 W magnetic field is desirable. The increase in sulfur removal percentage in the magnetic field of 4.5 W and 6.75 W is about 16.4% and 15.2%, respectively. According to the obtained results, the effect of temperature increase from 18.8°C to 23.4°C is more evident than the effect of temperature change from 23.4°C to 32.2°C. Because more thermal energy is needed to provide higher temperatures. Therefore, the temperature of 23.4°C is reported as the optimal temperature. The results of this research show that the percentage of sulfur removal is also high at this temperature. 展开更多
关键词 Oil and Gas Industries Optimized Energy Treatment Process Empirical investigation
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Model investigation of the low-carbon MgO-treated soil foundation based on CO_(2) overall carbonation
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作者 Guanghua Cai Songyu Liu +2 位作者 Yuqing Zhong Chisun Poon Jiangshan Li 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第11期2901-2916,共16页
The overall carbonation of MgO-admixed soil provides not only an efficient and environmentally friendly technique for improving soft ground but also a permanently safe solution for CO_(2) sequestration.To evaluate the... The overall carbonation of MgO-admixed soil provides not only an efficient and environmentally friendly technique for improving soft ground but also a permanently safe solution for CO_(2) sequestration.To evaluate the carbon sequestration potential and promote the carbonation application in soil improvement,a laboratory-scale model investigation is designed under pressurized carbonation considering the influences of MgO dosage and CO_(2) ventilation mode(way).The temperature,dynamic resilience modulus,and dynamic cone penetration(DCP)were tested to assess the carbonation treatment effect.The physical,strength,and microscopic tests were also undertaken to reveal the evolution mechanisms of CO_(2) migration in the MgO-carbonated foundation.The results indicate that the temperature peaks of MgO-treated foundation emerge at w20 h during hydration,but occur at a distance of 0e25 cm from the gas source within 6 h during carbonation.The dynamic resilience moduli of the model foundation increase by more than two times after carbonation and the DCP indices reduce dramatically.As the distance from the gas inlet increases,the bearing capacity,strength,and carbon sequestration decrease,whereas the moisture content increases.Compared to the end ventilation,the middle ventilation produces a higher carbonation degree and a wider carbonation area.The cementation and filling of nesquehonite and dypingite/hydromagnesite are verified to be critical factors for carbonation evolution and enhancing mechanical performances.Finally,the overall carbonation model is described schematically in three stages of CO_(2) migration.The outcomes would help to facilitate the practical application of CO_(2) sequestration in soil treatment. 展开更多
关键词 Model investigation Overall carbonation Reactive MgO Engineering properties Microscopic characteristics
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Experimental Investigation on the Strength and Ductility Performance of Steel-Timber-Steel Joints with Screw and Steel-Tube Fasteners
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作者 Huifeng Yang Mingwang Wu +3 位作者 Rixin Gu Hang Cao Kai Xiao Benkai Shi 《Journal of Renewable Materials》 EI 2023年第12期4175-4195,共21页
This article presents experimental results of steel-timber-steel(STS)joints loaded parallel to grain.Eight groups of specimens were designed,and tensile tests were performed.The fastener types and fastener numbers wer... This article presents experimental results of steel-timber-steel(STS)joints loaded parallel to grain.Eight groups of specimens were designed,and tensile tests were performed.The fastener types and fastener numbers were considered to evaluate the tensile strengths and ductility performances of the STS joints.The screws with 6 mm diameter and the innovative steel-tubes with 18 mm diameter were adopted as connecting fasteners.The experimental results were discussed in terms of yielding and ultimate strengths,slip stiffness,and ductility factors.The ductility classification and failure mechanisms of each group of specimens were analyzed.It was demonstrated that the STS joint with large diameter steel-tubes showed acceptable ductility,which was close to the ductility of the STS joint with small diameter screws,thanks to the hollow structure of the steel-tube.The theoretical strengths of various failure modes for the joints with small diameter screws or large diameter steel-tubes were calculated and compared with the experimental results.The ductile performance of the STS joint was discussed by comparing the theoretical strengths of various failure modes.The effective number of the STS joint with multifasteners was also analyzed by considering the failure mechanisms in aspects of tensile strength and slip stiffness. 展开更多
关键词 Steel-timber-steel joint SCREW steel-tube DUCTILITY experimental investigation timber structure
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Investigation and Analysis of HIV Infection among Unpaid Blood Donors in Wuzhou City
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作者 Lifei Liang Haiyan Wang +1 位作者 Qiong Zeng Meijie Zhou 《World Journal of AIDS》 2023年第2期19-27,共9页
Objective: To take the unpaid blood donors in Wuzhou City as the research object, analyze the characteristics and prevalence of HIV infection, further explore its epidemiological characteristics, and lay a solid found... Objective: To take the unpaid blood donors in Wuzhou City as the research object, analyze the characteristics and prevalence of HIV infection, further explore its epidemiological characteristics, and lay a solid foundation for the recruitment of unpaid blood donors and the safety of blood transfusion, so as to reduce the risk of HIV transmission through blood transfusion. Methods: This paper collected the anti-HIV test results of unpaid blood donors and the confirmation results of reactive samples from 2015 to 2020, and carried out statistical analysis on the relevant information of positive samples. Result: From 2015 to 2020, a total of 233,242 unpaid blood donors were tested, and the positive rate of anti-HIV initial screening was 0.057% (132/233,242), and the positive rate of anti-HIV confirmed was 0.022% (51/233,242);the comparison of positive rates in each year was P < 0.05. Among the total number of infections, 76.47% (39/51) of confirmed positive persons were infected with HIV alone, followed by combined TP infection, accounting for 15.69% (8/51);for the people between 46 and 55 years old, the infection rate was the highest, reaching 37.3%;and more men (90.2%) were infected than women. In terms of education background, junior high school and below were the majority, accounting for 58.83% of the total;in terms of marital status, the number of unmarried people was 27, accounting for 52.9%. In terms of occupation, there were two main groups: farmers and workers, accounting for 66.7% of the total number of infections, and students accounting for 15.7%. Among the confirmed positives, the proportion of first-time blood donors and whole blood donors was higher than that of those who donated blood again or donated component blood. Conclusion: The situation of HIV infection among unpaid blood donors in Wuzhou City was relatively stable from 2015 to 2020, with no significant change in the absolute number of infected people compared to the previous period (the HIV infection rate from 2010 to 2013 was 0.03%), and most of them were males, unmarried people and those with low education. Therefore, attention must be paid to the consultation and recruitment of blood donors before blood donation, as well as the HIV screening in the laboratory after blood donation, so as to ensure the safety of clinical blood use. 展开更多
关键词 Unpaid Blood Donors HIV Infection investigation
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A speckle noise suppression method based on surface waves investigation and monitoring data
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作者 Jingwei Gu Xiuzhong Li Yijun He 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第1期131-141,共11页
The internal energy distribution of waves can be described using ocean-wave spectra.In many ways,obtaining wave spectra on a global scale is critical.Surface waves investigation and monitoring onboard the Chinese-Fren... The internal energy distribution of waves can be described using ocean-wave spectra.In many ways,obtaining wave spectra on a global scale is critical.Surface waves investigation and monitoring onboard the Chinese-French oceanography satellite is the first space-borne instrument for detecting wave spectra specially,which was launched on October 29,2018.It can avoid the shortage of synthetic aperture radar detection results while still having some problems,especially with the effects of speckle noise.In this study,a method to suppress the speckle noise is proposed.First,the empirical formula for background speckle noise is established.Second,many spatio-temporal representative fluctuation spectra are classified and averaged.Third,rational transfer function filtering is used to obtain speckle noise close to the along-track direction.Finally,a signal-to-noise ratio threshold is used to suppress the abnormal speckle noise.This method solves the problems existing in previous denoising methods,such as excessive denoising in the along-track direction and the inability of some abnormal noises to be denoised in the two-dimensional directional wave spectra. 展开更多
关键词 speckle noise surface waves investigation and monitoring WaveWatch III wave spectra
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Analysis of Epidemiological Investigations and Responses to Human Rabies Deaths in Côte d’Ivoire, 2021
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作者 Issaka Tiembre Tetchi Sopi Malthide +2 位作者 Akani Bangama Christiane Djoman Joseph Benié Bi 《Open Journal of Epidemiology》 2023年第3期208-217,共10页
Rabies is an infectious disease that almost always leads to death as soon as the first signs appear, and is still endemic in several regions, including Côte d’Ivoire. Epidemiological investigations are carried o... Rabies is an infectious disease that almost always leads to death as soon as the first signs appear, and is still endemic in several regions, including Côte d’Ivoire. Epidemiological investigations are carried out and response measures implemented in the event of any death from human rabies. However, the quality of these investigations does not always allow the adoption of response measures. The aim of this work was to evaluate the reports of epidemiological investigations and response actions carried out during the occurrence of human rabies deaths from 2016 to 2018. This was a cross-sectional study that took place from April to September 2021 at the National Institute of Public Hygiene and focused on human rabies deaths notified from 206 to 2018. Of sixty-one (61) human rabies deaths recorded, sixty (60) were investigated, among which fifty-nine (59) deaths had been subject to response. Most deaths occurred in rural areas (75%), and the main vector was the dog (98%). Several shortcomings were noted: response actions were not carried out promptly;joint interventions bringing together human and animal health professionals were rare, there was little communication about rabies to communities (36%), and very little vaccination of the vector, the source of the disease (12%);an almost total absence of capacity-building for local players (7%);the health districts of Abobo-Ouest, Bondoukou, Divo and Fresco, which had regularly recorded human rabies deaths, had not benefited from dog vaccination, which is supposed to break the circulation of the virus. The persistence of rabies deaths in the health districts could probably be linked to these shortcomings. Faced with these realities, it is essential to strengthen the epidemiological investigation capacities of the players involved, in order to improve the quality of investigations and ensure an effective response. 展开更多
关键词 Epidemiological investigations RESPONSE Human Rabies Côte d’Ivoire
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Investigation and Hazard Assessment of Invasive Alien Plants on the Campus of Tongren University
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作者 Tinghong TAN Yingying HE +4 位作者 Zide YANG Siyu XIA Li LUO Hong YANG Lan WANG 《Plant Diseases and Pests》 CAS 2023年第4期33-37,共5页
[Objectives]The paper was to investigate and assess the species,distribution and hazard status of invasive alien plants on the campus of Tongren University.[Methods]A survey was conducted using line survey method,and ... [Objectives]The paper was to investigate and assess the species,distribution and hazard status of invasive alien plants on the campus of Tongren University.[Methods]A survey was conducted using line survey method,and the risk assessment index system of invasive alien plants was established by analytic hierarchy process(AHP).[Results]There were 11 species of invasive alien plants on the campus of Tongren University,belonging to 8 genera and 5 families.There were 6 species of invasive alien plants belonging to Asteraceae,accounting for 54.55%of the total.In terms of the origin of invasive plants,most of them were native to North America and Europe,accounting for 27.27%of the total.In terms of harmful level,there were no high-risk invasive plants on the campus of Tongren University,but Alternanthera philoxeroides had the highest score and was the most harmful.[Conclusions]The present situation of alien plant invasion on the campus of Tongren University is closely related to the ecological environment of the campus.It is suggested to strengthen the management of campus plants,focus on the prevention and control of A.philoxeroides,and carry out regular investigation of invasive alien plants on campus to ensure the ecological safety of the campus. 展开更多
关键词 Tongren University Invasive alien plants Plant investigation Analytic hierarchy process Hazard assessment
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3D Model Construction and Ecological Environment Investigation on a Regional Scale Using UAV Remote Sensing
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作者 Chao Chen Yankun Chen +7 位作者 Haohai Jin Li Chen Zhisong Liu Haozhe Sun Junchi Hong Haonan Wang Shiyu Fang Xin Zhang 《Intelligent Automation & Soft Computing》 SCIE 2023年第8期1655-1672,共18页
The acquisition of digital regional-scale information and ecological environmental data has high requirements for structural texture,spatial res-olution,and multiple parameter categories,which is challenging to achiev... The acquisition of digital regional-scale information and ecological environmental data has high requirements for structural texture,spatial res-olution,and multiple parameter categories,which is challenging to achieve using satellite remote sensing.Considering the convenient,facilitative,and flexible characteristics of UAV(unmanned air vehicle)remote sensing tech-nology,this study selects a campus as a typical research area and uses the Pegasus D2000 equipped with a D-MSPC2000 multi-spectral camera and a CAM3000 aerial camera to acquire oblique images and multi-spectral data.Using professional software,including Context Capture,ENVI,and ArcGIS,a 3D(three-dimensional)campus model,a digital orthophoto map,and multi-spectral remote sensing map drawing are realized,and the geometric accuracy of typical feature selection is evaluated.Based on a quantitative remote sensing model,the campus ecological environment assessment is performed from the perspectives of vegetation and water body.The results presented in this study could be of great significance to the scientific management and sustainable development of regional natural resources. 展开更多
关键词 Unmanned air vehicle multi-spectral camera oblique photography 3D model construction ecological environment investigation regional scale
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