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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 被引量:1
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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 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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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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Numerical investigation of friction-heating-pressurization and its control parameters in the shear band of high-speed landslides
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作者 ZHAO Nenghao CUI Shenghua LU Haijun 《Journal of Mountain Science》 SCIE CSCD 2024年第10期3380-3395,共16页
High-speed sliding often leads to catastrophic landslides,many of which,in the initial sliding phase before disintegration,experience a friction-induced thermal pressurization effect in the bottom shear band,accelerat... High-speed sliding often leads to catastrophic landslides,many of which,in the initial sliding phase before disintegration,experience a friction-induced thermal pressurization effect in the bottom shear band,accelerating the movement of the overlying sliding mass.To quantitatively investigate this complex multiphysical phenomenon,we established a set of equations that describe the variations in temperature and excess pore pressure within the shear band,as well as the conservation of momentum equation for the overlying sliding mass.With a simplified landslide model,we investigated the variations of temperature and excess pore pressure within the shear band and their impacts on the velocity of the overlying sliding mass.On this basis,we studied the impact of seven key parameters on the maximum temperature and excess pore pressure in the shear band,as well as the impact on the velocity of the overlying sliding mass.The simulation results of the standard model show that the temperature and excess pore pressure in the shear band are significantly higher than those in the adjacent areas,and reach the maximum values in the center.Within a few seconds after the start,the maximum excess pore pressure in the shear zone is close to the initial stress,and the shear strength loss rate exceeds 90%.The thermal pressurization mechanism significantly increases the velocity of the overlying sliding mass.The results of parameter sensitivity analysis show that the thermal expansion coefficient has the most significant impact on the temperature and excess pore pressure in the shear band,and the sliding surface dip angle has the most significant impact on the velocity of the overlying sliding mass.The results of this study are of great significance for clarifying the mechanism of thermal pressurization-induced high-speed sliding. 展开更多
关键词 High-speed landslide Shear band Friction-heating-pressurization Numerical investigation
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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 Study on the Implementation Path of the Blended Teaching Model in Geological Hazards Investigation and Evaluation
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作者 Liu Yang Wenjuan Wang +2 位作者 Weijian Zhou Dan Wang Ping Yin 《Journal of Contemporary Educational Research》 2024年第9期106-111,共6页
Geological Hazards Investigation and Evaluation is the core course of Environmental Geological Engineering,aiming to cultivate skilled talents with solid theoretical knowledge and excellent practical skills.At present... Geological Hazards Investigation and Evaluation is the core course of Environmental Geological Engineering,aiming to cultivate skilled talents with solid theoretical knowledge and excellent practical skills.At present,the course faces several issues,including a teaching environment disconnected from real-world work scenarios,course content that deviates from job-related tasks,a lack of digital teaching resources,and reliance on a single teaching method,leading to students’poor feedback from employers.Based on the concept of outcome-based education,the course team of Geological Hazards Investigation and Evaluation establishes a“five-step double-rotation”blended teaching model with the help of a Small Private Online Course platform.The program is designed to improve the teaching environment and expand the digitalized teaching resources in order to improve students’learning motivation,enhance learning effectiveness,and cultivate skillful talents who meet employers’satisfaction. 展开更多
关键词 Outcome-based education concept Geological Hazards investigation and Evaluation Teaching mode Blended teaching and learning
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Investigation on Color Pattern Diversity of Overwintering Harmonia axyridis in Southern Suburb of Jiamusi 被引量:1
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作者 李佳琳 可晓斌 +3 位作者 王卓微 周丽娜 王景元 罗志文 《Plant Diseases and Pests》 CAS 2011年第4期40-42,共3页
Five sampling points for Harmonia axyridis (Pallas) were set in Sifeng Mountain scenic spot and four school districts of Jiamusi University, and diversity of color pattern of overwintering H. axyridis was surveyed f... Five sampling points for Harmonia axyridis (Pallas) were set in Sifeng Mountain scenic spot and four school districts of Jiamusi University, and diversity of color pattern of overwintering H. axyridis was surveyed from October to December in 2010. Survey results found that there were 16 color patterns of H. axyridis in southern suburb of Jiamusi, 11 species showed yellow background, while the other 5 species were black background, accounting for 68.75% and 31.25% of all the species, respectively. The majority of H. axyridis with yellow background had 18 or 19 spots. Compared with the sampling data in 2006 and 2008, the propor- tions of the color patterns had no significant difference in different years, but it slightly varied with the changes of environment. 展开更多
关键词 Harmonia axyridis Color patterns DIVERSITY investigation China
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Investigation and Analysis on Agricultural Resources in the Main Living Areas of Pumi Nationality in Yunnan Province 被引量:1
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作者 杨少华 康平德 +4 位作者 郭承刚 陈翠 徐福荣 汤王外 徐中志 《Agricultural Science & Technology》 CAS 2011年第11期1691-1698,共8页
[Objective] To fully grasp the living environment and the use of agricultural resources of Pumi nationality, a minority group specific in Yunnan. [Methods]Field investigation and analysis were conducted on the social ... [Objective] To fully grasp the living environment and the use of agricultural resources of Pumi nationality, a minority group specific in Yunnan. [Methods]Field investigation and analysis were conducted on the social economic conditions, living environment, types of agricultural resources and their use in the main inhabitances of Pumi people including Yulong, Ninglang, Lanping and Weixi County in Yunnan. [Result] There are certain differences in social and economic situations of the four counties, and the ecological environment is generally good. The main agricultural resources in villages under investigation include beans and coarse cereals, while there are certain differences among other agricultural resources due to their location. [Conclusion] The living environment of the main inhabitances of Pumi people in Yunnan is good and there are plenty and characteristic agricultural resources which have certain potentiality for development in the future. 展开更多
关键词 YUNNAN Pumi nationality Inhabit investigation Agricultural resources analysis
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Investigation of Main Fungal Diseases of Pepper (Piper nigrum L.) in Hainan Province and Their Pathogen Identification
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作者 崔昌华 郑服丛 +3 位作者 贺春萍 李锐 何小兵 郑肖兰 《Plant Diseases and Pests》 CAS 2011年第2期1-5,共5页
[ Objective ] The paper was to confirm the current major diseases of pepper in Hainan Province and their corresponding pathogens. [ Method ] The pep- per gardens in 13 main cultivation regions of pepper in Hainan Prov... [ Objective ] The paper was to confirm the current major diseases of pepper in Hainan Province and their corresponding pathogens. [ Method ] The pep- per gardens in 13 main cultivation regions of pepper in Hainan Province were systematically investigated, and the pathogens of the obtained specimens were isolated and identified. [ Result] Seven fungal diseases in pepper were totally investigated, including blast, anthracnose, blight, slow wilt, root rot, basal rot and scleretin- ia disease. Currently, the diseases with serious damage on pepper include blast, anthracnese, blight and slow wilt. [ Conclusion] The result provides the theoreti- cal basis for the integrated control of diseases in pepper, and is also benefit for scientific research workers to master the latest dynamic of diseases. 展开更多
关键词 PEPPER Disease investigation Pathogen identification
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Investigation and Analysis of Autumn and Winter Ornamental Landscape Plants in Kuitun City of Xinjiang
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作者 杨逢玉 何磊 郭润华 《Journal of Landscape Research》 2010年第8期11-13,共3页
Through field investigation on autumn and winter ornamental landscape plants in representative main roads, residential areas and parks of Kuitun City and based on relevant materials, the disposition and landscaping of... Through field investigation on autumn and winter ornamental landscape plants in representative main roads, residential areas and parks of Kuitun City and based on relevant materials, the disposition and landscaping of these plants were analyzed from the perspectives of plant species, ornamental characteristics and landscape creation. The result showed that autumn and winter landscape plants in Kuitun City were primarily evergreen coniferous and deciduous trees outstanding for their shapes and colors, and that landscape was created through different types of plant disposition. Especially colors of trunks, barks, leaves, winter buds and fruits' colors provided favorable conditions for appreciating plants in autumn and winter. Finally, suggestions were proposed according to the investigation and analysis of autumn and winter ornamental plants in Kuitun City, so as to provide reference for future construction and development of landscape plants. 展开更多
关键词 Landscape PLANTS AUTUMN and WINTER ORnameNTAL PLANTS investigation Kuitun CITY
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An Investigation of Avoidance of Relative Clauses in the English Writings of High Vocational College Students
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作者 张劲柏 吴婧 《海外英语》 2015年第9期236-238,共3页
This study investigates the avoidance of relative clauses by high vocational college students and also explores the differences in the avoidance of the RCs by high-level students and low-level students in their Englis... This study investigates the avoidance of relative clauses by high vocational college students and also explores the differences in the avoidance of the RCs by high-level students and low-level students in their English writings. The data used in this study have been collected from English writing tasks and analyzed by Statistical Package for Social Sciences(SPSS17.0). The major findings of this study are stated as follows: 1) There are significant differences in the production of the relative clauses in their English writings by Chinese higher vocational college students and English native speakers. Avoidance of relative clauses exists in the English writings of higher vocational college students. 2) High-level Chinese higher vocational college students display less of the avoidance phenomenon in their English writings than low-level students. 展开更多
关键词 AVOIDANCE relative CLAUSES English writing investigation higher VOCATIONAL COLLEGE students
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Investigation and Survey of Graduate Employment of Business English Major——In the case of JMI
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作者 张金艳 《海外英语》 2017年第21期243-244,共2页
Business English Major is the key specialty in Jiangsu Maritime Institute.Grasping and understanding the situation of graduates is of very important meaning to the major construction and the personnel cultivating prog... Business English Major is the key specialty in Jiangsu Maritime Institute.Grasping and understanding the situation of graduates is of very important meaning to the major construction and the personnel cultivating program.This article is mainly about the investigation and survey of graduate of 2011,and rational suggestions will be put forward on improving the quality of graduate and the major construction and the personnel cultivating program. 展开更多
关键词 Business English Major EMPLOYMENT investigation personnel cultivating program
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Application of the High-resolution EM Method in the Investigation of B Tunnel 被引量:2
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作者 何兰芳 何展翔 +2 位作者 王绪本 张希哲 杨轮凯 《Applied Geophysics》 SCIE CSCD 2005年第3期140-144,i0001,共6页
A successful case history of exploring for concealed structure using the high-resolution EM method in the investigation of the West-East Gas Pipeline Project's B Tunnel is presented in this paper. The high frequency ... A successful case history of exploring for concealed structure using the high-resolution EM method in the investigation of the West-East Gas Pipeline Project's B Tunnel is presented in this paper. The high frequency electromagnetic image system named STRATAGEM EH4, operating at frequencies ranging from 90KHz to 1Hz, was used for data acquisition. The orthogonal components of the electromagnetic field were measured during the field acquisition and the relevant electromagnetic attributes of the object body were extracted from the electromagnetic data. Hybrid sources, consisting of natural and full tensor-controlled sources, were utilized to produce high-quality electromagnetic field data. B Tunnel lies in the western part of Hubei province, at depths of less than 200m. The geologic setting of B tunnel is very complex. Following an initial geologic investigation, an outcrop considered to be a bedrock interface by investigators, collapsed during tunneling operations. A second investigation applied high-resolution EM and seismic refraction methods to reveal a more complex geologic structure along the tunnel route. The predicted rock classes and fault were encountered during the subsequent tunneling operations. 展开更多
关键词 HFEM HREM Concealed Structure and tunnel investigation
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Damage investigation of girder bridges under the Wenchuan earthquake and corresponding seismic design recommendations 被引量:70
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作者 Li Jianzhong Peng Tianbo Xu Yan 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2008年第4期337-344,共8页
An investigation of girder bridges on National Highway 213 and the Doujiangyan-Wenchuan expressway after the Wenchuan earthquake showed that typical types of damage included: span collapses due to unseating at expans... An investigation of girder bridges on National Highway 213 and the Doujiangyan-Wenchuan expressway after the Wenchuan earthquake showed that typical types of damage included: span collapses due to unseating at expansion joints; shear key failure; and damage of the expansion joint due to the slide-induced large relative displacement between the bottom of the girder and the top of the laminated-rubber bearing. This slide, however, can actually act as a form of isolation for the substructure, and as a result, the piers and foundation of most of the bridges on state route 213 suffered minor damage. The exception was the Baihua Bridge, which suffered severe damage. Corresponding seismic design recommendations are presented based on this investigation. 展开更多
关键词 Wenchuan earthquake bridge damage investigation seismic design recommendation
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Epidemiological Investigation and Genome Analysis of Duck Circovirus in Southern China 被引量:11
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作者 Chun-he Wan Guang-hua Fu Shao-hua Shi Long-fei Cheng Hong-mei Chen Chun-xiang Peng Su Lin Yu Huang 《Virologica Sinica》 SCIE CAS CSCD 2011年第5期289-296,共8页
Duck circovirus (DuCV), a potential immunosuppressive virus, was investigated in Southern China from March 2006 to December 2009 by using a polymerase chain reaction (PCR) based method. In this study, a total of 1... Duck circovirus (DuCV), a potential immunosuppressive virus, was investigated in Southern China from March 2006 to December 2009 by using a polymerase chain reaction (PCR) based method. In this study, a total of 138 sick or dead duck samples from 18 different farms were examined with an average DuCV infection rate of-35%. It was found that ducks between the ages of 40~60 days were more susceptible to DuCV. There was no evidence showing that the DuCV virus was capable of vertical transmission. Farms with positive PCR results exhibited no regularly apparent clinical abnormalities such as feathering disorders, growth retardation or lower-than-average weight. The complete genomes of 91 strains from Fujian Province and 1 from Zhejiang Province were sequenced and analyzed. The 10 DuCV genomes, comlbared with others genomes downloaded from GenBank, ranged in size from 1988 to 1996 base pairs, with sequence identities ranging from 83.2% to 99.8%. Phylogenetic analysis based on genome sequences demonstrated that DuCVs can be divided into two distinct genetic genotypes, Group I (the Euro-USA lineage) and Group II(the Taiwan lineage), with approximately 10.0% genetic difference between the two types. Molecular epidemiological data suggest there is no obvious difference among DuCV strains isolated from different geographic locations or different species, including Duck, Muscovy duck, Mule duck, Cheery duck, Mulard duck and Pekin duck. 展开更多
关键词 Duck circovims(DuCV) Epidemiological investigation GENOME Phylogenetic analysis
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Industrially Experimental Investigations and Development of the Curve-ROD Baffle Heat Exchanger 被引量:7
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作者 严良文 吴金星 王志文 《Journal of Shanghai University(English Edition)》 CAS 2004年第3期337-341,共5页
The conventional heat exchanger with segmental baffles is prone to bring forth fluid-induced vibration of heat transfer tubes and increase the pressure drop of shell-side greatly at higher fluid flow velocity. In orde... The conventional heat exchanger with segmental baffles is prone to bring forth fluid-induced vibration of heat transfer tubes and increase the pressure drop of shell-side greatly at higher fluid flow velocity. In order to avoid the above defects, the ROD-baffle heat exchanger has been developed. However, its collocation of heat transfer tubes is conventionally in square, which leads to fewer heat transfer area per unit volume. Based on the ROD-baffle heat exchanger, a new type curve-ROD baffle has been developed, and an industrial investigation of the curve-ROD baffle heat exchanger with normal triangular collocation has been carried into execution. In this paper, two equations using the Reynolds number were acquired to predict the heat transfer coefficients of the shell-side and tube-side. The experimental results show that the shell-side heat transfer and pressure drop characteristics of the curve-ROD baffle heat exchanger are superior to those of the segmental baffle one. 展开更多
关键词 heat exchanger curve-ROD baffle heat transfer pressure drop experimental investigation.
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Experimental Investigation of the Characteristics of an Artificial Cavity During the Water-Exit of a Slender Body 被引量:4
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作者 Guoqiang Fu Jiaolong Zhao +1 位作者 Liping Sun Yang Lu 《Journal of Marine Science and Application》 CSCD 2018年第4期578-584,共7页
Experimental studies are carried out with slender bodies vertically exiting out of the water using a high-speed camera. The mechanisms for the formation, development, and collapse of the cavity around the slender body... Experimental studies are carried out with slender bodies vertically exiting out of the water using a high-speed camera. The mechanisms for the formation, development, and collapse of the cavity around the slender body are explored. The dynamic characteristics of the shoulder cavity and the trail cavity during the water-exit of low-speed bodies are analyzed for various water depths and initial velocities. The results show that the initial velocity has a great influence on the formation, development, and collapse of the cavity. The length and the thickness of the shoulder cavity vary non-linearly with the depth. 展开更多
关键词 Water-exit Slender BODY CAVITY development CAVITY COLLAPSE EXPERIMENTAL investigation
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Theoretical and Experimental Investigation of Flexural Vibration Transfer Properties of High-Pressure Periodic Pipe 被引量:4
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作者 魏振东 李宝仁 +1 位作者 杜经民 杨钢 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第4期68-71,共4页
According to the theory of phononic crystals, the hydraulic pipeline is designed to be a periodic structure composed of steel pipes and hoses to suppress the vibration of the hydraulic system with band gaps. We presen... According to the theory of phononic crystals, the hydraulic pipeline is designed to be a periodic structure composed of steel pipes and hoses to suppress the vibration of the hydraulic system with band gaps. We present theoretical and experimental investigations into the flexural vibration transfer properties of a high-pressure periodic pipe with the force on the inner pipe wall by oii pressure taken into consideration. The results show that the vibration attenuation of periodic pipe decreases along with the elevation of working pressure for the hydraulic system, and the band gaps in low frequency ranges move towards high frequency ranges. The periodic pipe has good vibration attenuation performance in the frequency range below 1000 Hz and the vibration of the hydraulic system is effectively suppressed. A11 the results are validated by experiment. The experimental results show a good agreement with the numerical calculations, thus the flexural vibration transfer properties of the high- pressure periodic pipe can be precisely calculated by taking the fluid structure interaction between the pipe and oil into consideration. This study provides an effective way for the vibration control of the hydraulic system. 展开更多
关键词 of on in theoretical and Experimental investigation of Flexural Vibration Transfer Properties of High-Pressure Periodic Pipe IS
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Environmental Investigation and Evaluation of Land Subsidence in the Datong Coalfield Based on InSAR Technology 被引量:5
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作者 JIA Xiuming MA Chao ZHAO Anyuan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第5期1035-1044,共10页
Heavy mining of Jurassic and Carboniferous horizontal coal seams in the Datong coalfield has seriously affected the local geological environment, which is mainly manifested by such geohazards as soil avalanches, lands... Heavy mining of Jurassic and Carboniferous horizontal coal seams in the Datong coalfield has seriously affected the local geological environment, which is mainly manifested by such geohazards as soil avalanches, landslides, mudflows, surface subsidence, surface cracks, surface solid waste accumulation and surface deformation. More seriously, coal mining causes groundwater to leak. Overpumping of groundwater has resulted in substantial land subsidence of the urban area in Datong City. Based on the previous geo-environmental investigation in the work area, the authors used radar remote sensing techniques such as InSAR (synthetic aperture radar interferometry) and D-InSAR (differential synthetic aperture radar interferometry), supplemented by the optical remote sensing method, for geo-environmental investigation to ascertain the geo-environmental background of the Datong Jurassic and Carboniferous-Permian coalfield and evaluate the effects of the geohazards, thus providing a basis for the geo-environmental protection, geohazard control and prevention, land improvement and optimization of the human environment. In this study 8 cog-nominal ERS-1/2 SAR data frames during 1992 to 2003 were used, but the following processing was made: (1) the multitemporal SAR magnitude images were used to interpret the geological structure, vegetation, microgeomorphology and drainage system; (2) the multi-temporal InSAR coherent images were used to make a classification of surface features and evaluate the coherence change due to coal mining; and (3) the multi-temporal cog-nominal SAR images were used to complete D-InSAR processing to remove the information of differential deformation areas (sites). In the end, a ten-year time series of differential interferograms were obtained using the multi-temporal cog-nominal SAR images. In the tests, 84 deformed areas (sites) were obtained, belonging to those in 1993-1996, 1996-1997, 1997-1998, 1998-2001, 1998-2002 and 2001-2003 respectively. Of the 84 areas, 44 are mining subsidence ones, 23 urban subsidence ones and 17 landslide subsidence ones. They cover a total area of 1824.4 km^2, equivalent to the area of the whole Datong coalfield. Then an accurate evaluation was made on the geo-environment of the Datong coalfield. The tests show that InSAR is now the only feasible technical means for making one all-weather, real-time measurement of a coal mining land subsidence area covering up to 10,000 km^2 to subcentimeter resolution. This study is a successful application of InSAR in the investigation and evaluation of land subsidence, especially in coal mining areas. 展开更多
关键词 environmental investigation synthetic aperture radar interferometry (InSAR) Datong coalfield
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Experimental investigation of dynamic characteristics of leaching tubing for solution mining of salt cavern carbon and energy storage
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作者 Yin-Ping Li Xin-Bo Ge +1 位作者 Xi-Lin Shi Hong-Ling Ma 《Petroleum Science》 SCIE EI CAS CSCD 2024年第4期2703-2722,共20页
Salt caverns are extensively utilized for storing various substances such as fossil energy,hydrogen,compressed air,nuclear waste,and industrial solid waste.In China,when the salt cavern is leached through single-well ... Salt caverns are extensively utilized for storing various substances such as fossil energy,hydrogen,compressed air,nuclear waste,and industrial solid waste.In China,when the salt cavern is leached through single-well water solution mining with oil as a cushion,engineering challenges arise with the leaching tubing,leading to issues like damage and instability.These problems significantly hinder the progress of cavern construction and the control of cavern shape.The primary cause of this is the flowinduced vibration instability of leaching tubing within a confined space,which results in severe bending or damage to the tubing.This study presents a model experimental investigation on the dynamic characteristics of leaching tubing using a self-developed liquid-solid coupling physical model experiment apparatus.The experiment utilizes a silicone-rubber pipe(SRP)and a polycarbonate pipe(PCP)to examine the effects of various factors on the dynamic stability of cantilevered pipes conveying fluid.These factors include external space constraint,flexural rigidity,medium outside the pipe,overhanging length,and end conditions.The experiments reveal four dynamic response phenomena:water hammer,static buckling,chaotic motion,and flutter instability.The study further demonstrates that the length of the external space constraint has a direct impact on the flutter critical flow velocity of the cantilevered pipe conveying fluid.Additionally,the flutter critical flow velocity is influenced by the end conditions and different external media. 展开更多
关键词 Salt cavern storage Solution mining Leaching tubing Experimental investigation Flutter instability
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