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Identifying the Hydrochemical Characteristics,Genetic Mechanisms and Potential Human Health Risks of Fluoride and Nitrate Enriched Groundwater in the Tongzhou District,Beijing,North China
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作者 ZHANG Shouchuan LIU Kai +2 位作者 MA Yan WANG Luyao SUN Junliang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第2期468-476,共9页
Fluoride and nitrate enriched groundwater are potential threats to the safety of the groundwater supply that may cause significant effects on human health and public safety,especially in aggregated population areas an... Fluoride and nitrate enriched groundwater are potential threats to the safety of the groundwater supply that may cause significant effects on human health and public safety,especially in aggregated population areas and economic hubs.This study focuses on the high F^(−)and NO_(3)^(−)concentration groundwater in Tongzhou District,Beijing,North China.A total of 36 groundwater samples were collected to analyze the hydrochemical characteristics,elucidate genetic mechanisms and evaluate the potential human health risks.The results of the analysis indicate:Firstly,most of the groundwater samples are characterized by Mg-HCO_(3) and Na-HCO_(3) with the pH ranging from 7.19 to 8.28 and TDS with a large variation across the range 471-2337 mg/L.The NO_(3)^(−)concentration in 38.89%groundwater samples and the F^(−)concentration in 66.67%groundwater samples exceed the permissible limited value.Secondly,F^(−)in groundwater originates predominantly from water-rock interactions and the fluorite dissolution,which is also regulated by cation exchange,competitive adsorption of HCO_(3)−and an alkaline environment.Thirdly,the effect of sewage disposal and agricultural activities have a significant effect on high NO3-concentration,while the high F^(−)concentration is less influenced by anthropogenic activity.The alkaline environment favors nitrification,thus being conducive to the production of NO_(3)^(−).Finally,the health risk assessment is evaluated for different population groups.The results indicate that high NO_(3)^(−)and F^(−)concentration in groundwater would have the largest threat to children’s health.The findings of this study could contribute to the provision of a scientific basis for groundwater supply policy formulation relating to public health in Tongzhou District. 展开更多
关键词 fluoride concentration nitrate pollution genetic mechanism health risk assessment Tongzhou district
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Optimization of Agricultural Industrial Structure in Changping District of Beijing Based on Grey Relational Analysis
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作者 Haosong LI Rao CHEN 《Asian Agricultural Research》 2024年第4期3-7,共5页
In the economic development of Beijing,although the share of the total amount of agricultural industry in the overall economy is relatively low,it has an important impact on the daily life of residents,social stabilit... In the economic development of Beijing,although the share of the total amount of agricultural industry in the overall economy is relatively low,it has an important impact on the daily life of residents,social stability and the development of other industries.Changping District,as an important agricultural production base of Beijing,its agricultural development has an indispensable strategic significance for the stability and growth of the entire regional economy.Therefore,it is very important to study the structure of agricultural industry in Changping District.Based on the detailed analysis of the agricultural industrial structure of Changping District,this paper uses the grey relation theory to analyze the different industries in the agricultural industrial structure of Changping District,including planting,forestry,animal husbandry,fishery and agricultural,forestry,service industries,in order to reveal the impact of these industries on the agricultural industrial structure of Changping District.Through this study,it comes up with specific and feasible suggestions for the optimization of agricultural industrial structure in Changping District,and provides valuable reference for the agricultural development of other areas in Beijing. 展开更多
关键词 GREY RELATION theory Changping district AGRICULTURAL INDUSTRIAL structure
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Acceptability of Ambulatory Surgical Services and Its Predictors among Residents of Budondo Sub-County—Jinja District, Uganda
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作者 Anna Turumanya Kalumuna 《Surgical Science》 2023年第3期170-191,共22页
Background: 25% of all people requiring surgical care are not able to access it due to its high cost. These people stand a high risk of preventable severe morbidity and mortality due to poor prognosis of surgically co... Background: 25% of all people requiring surgical care are not able to access it due to its high cost. These people stand a high risk of preventable severe morbidity and mortality due to poor prognosis of surgically correctable illnesses. Ambulatory surgical care services are significantly cheaper than orthodox surgical care and have become very relevant in this time and age where health conditions that can only be treated with surgical intervention are on the rise. The acceptability of ambulatory surgical care services will determine how this model increases universal health coverage. Objective: To assess the acceptability of ambulatory surgical services and its predictors among residents of Budondo Sub-County—Jinja district. Methods: The study was cross-sectional targeting 371 household heads in Budondo Sub-County, which was stratified by parish, with villages in each randomly sampled. Systematic random sampling was used to sample households and households therein were purposively sampled. Structured interviews and questionnaires were the data collection techniques, and data was analyzed in SPSS version 25 using descriptive statistics and a binomial logit model. Results: The level of acceptability of ambulatory surgical care services among residents of Budondo Sub-County was found to be near-universal, at 96.5%. The odds of accepting ambulatory surgical care were least among household heads who agreed that surgery done in a hospital would be cheaper than surgery done at community level (aOR = 0.174 [CI = 0.055 - 0.553]), those who had health insurance (aOR = 0.105 [95% CI = 0.030 - 0.371]), and household heads who were covered with private health insurance (aOR = 0.078 [95% CI = 0.008 - 0.792]). Acceptability of ASC was higher among household heads who agreed that they would trust ambulatory surgical centers with their life were more likely to accept ambulatory surgical care (aOR = 1.124, [95% CI = 1.122 - 3.218], P = 0.000), and household heads from households that had less than five members with surgery history were twice as likely to accept ambulatory surgical care (aOR = 2.431 [95% CI = 1.122 - 5.898], P = 0.000). Conclusion: Acceptability of ambulatory surgical care services among residents of Budondo Sub-County is high, and near-universal. It is mainly predicted by intrapersonal correlates and to a small extent by socio-demographic characteristics, with the implication that the administration of Global Surgical Initiatives in Kyabirwa ought to focus on modifying or uphold the intrapersonal characteristics found to be antagonists and protagonists of acceptability, respectively. 展开更多
关键词 ACCEPTABILITY Ambulatory Surgery PREDICTORS jinja district
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Evaluation and Improvement Strategies for Slow Traffic Systems Based on Multi-source Big Data:A Case Study of Shijingshan District of Beijing City
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作者 LI Yiwen 《Journal of Landscape Research》 2023年第4期62-64,68,共4页
The slow traffic system is an important component of urban transportation,and the prerequisite and necessary condition for Beijing to continue promoting“green priority”are establishing a good urban slow traffic syst... The slow traffic system is an important component of urban transportation,and the prerequisite and necessary condition for Beijing to continue promoting“green priority”are establishing a good urban slow traffic system.Shijingshan District of Beijing City is taken as a research object.By analyzing and processing population distribution data,POI data,and shared bicycle data,the shortcomings and deficiencies of the current slow traffic system in Shijingshan District are explored,and corresponding solutions are proposed,in order to provide new ideas and methods for future urban planning from the perspective of data. 展开更多
关键词 Multi-source data Slow traffic system Shijingshan district
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Big Data Analysis and Optimization Suggestions of Cultural Facilities in Shijingshan District,Beijing City
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作者 KANG Yue YUAN Leyi DING Zhengli 《Journal of Landscape Research》 2023年第2期49-53,共5页
With the successful holding of Beijing Winter Olympic Games in 2022,the planning and cultural services of Shijingshan District have been reviewed,but the systematic planning theory has not been fully applied.Through t... With the successful holding of Beijing Winter Olympic Games in 2022,the planning and cultural services of Shijingshan District have been reviewed,but the systematic planning theory has not been fully applied.Through the big data research method,the location advantages and disadvantages of Shijingshan District were analyzed,and the distribution of its cultural facilities was defined.Feasible optimization schemes were proposed according to its advantages and disadvantages as well as the experience and conditions of the Winter Olympics. 展开更多
关键词 BEIjinG Shijingshan district Cultural service facilities Big data Renovation of old functional areas
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The Operating Revenue of Jinbo Bio-Pharmaceutical for 2023 Reaching 0.78 Billion yuan
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《China Detergent & Cosmetics》 CAS 2024年第2期5-5,共1页
In Mar.20th,2024,Jinbo Bio-Pharmaceutical released the first performance report since it was listed at Beijing Stock Exchange,with many data hitting a record high.The company realized an operating revenue of 0.78 bill... In Mar.20th,2024,Jinbo Bio-Pharmaceutical released the first performance report since it was listed at Beijing Stock Exchange,with many data hitting a record high.The company realized an operating revenue of 0.78 billion yuan,with a year-on-year increase of 99.96%,and hitting a new high for the past five years.The net profit attributable to shareholders was 0.3 billion yuan,with a year-on-year increase of 174.6%.The net profit attributable to shareholders after deducting non recurring gains and losses was 0.286 billion yuan,with a year-on-year increase of 181.02%. 展开更多
关键词 REVENUE LISTED jin
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Effects of drip and flood irrigation on carbon dioxide exchange and crop growth in the maize ecosystem in the Hetao Irrigation District,China
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作者 LI Chaoqun HAN Wenting PENG Manman 《Journal of Arid Land》 SCIE CSCD 2024年第2期282-297,共16页
Drip irrigation and flood irrigation are major irrigation methods for maize crops in the Hetao Irrigation District,Inner Mongolia Autonomous Region,China.This research delves into the effects of these irrigation metho... Drip irrigation and flood irrigation are major irrigation methods for maize crops in the Hetao Irrigation District,Inner Mongolia Autonomous Region,China.This research delves into the effects of these irrigation methods on carbon dioxide(CO_(2))exchange and crop growth in this region.The experimental site was divided into drip and flood irrigation zones.The irrigation schedules of this study aligned with the local commonly used irrigation schedule.We employed a developed chamber system to measure the diurnal CO_(2)exchange of maize plants during various growth stages under both drip and flood irrigation methods.From May to September in 2020 and 2021,two sets of repeated experiments were conducted.In each experiment,a total of nine measurements of CO_(2)exchange were performed to obtain carbon exchange data at different growth stages of maize crop.During each CO_(2)exchange measurement event,CO_(2)flux data were collected every two hours over a day-long period to capture the diurnal variations in CO_(2)exchange.During each CO_(2)exchange measurement event,the biological parameters(aboveground biomass and crop growth rate)of maize and environmental parameters(including air humidity,air temperature,precipitation,soil water content,and photosynthetically active radiation)were measured.The results indicated a V-shaped trend in net ecosystem CO_(2)exchange in daytime,reducing slowly at night,while the net assimilation rate(net primary productivity)exhibited a contrasting trend.Notably,compared with flood irrigation,drip irrigation demonstrated significantly higher average daily soil CO_(2)emission and greater average daily CO_(2)absorption by maize plants.Consequently,within the maize ecosystem,drip irrigation appeared more conducive to absorbing atmospheric CO_(2).Furthermore,drip irrigation demonstrated a faster crop growth rate and increased aboveground biomass compared with flood irrigation.A strong linear relationship existed between leaf area index and light utilization efficiency,irrespective of the irrigation method.Notably,drip irrigation displayed superior light use efficiency compared with flood irrigation.The final yield results corroborated these findings,indicating that drip irrigation yielded higher harvest index and overall yield than flood irrigation.The results of this study provide a basis for the selection of optimal irrigation methods commonly used in the Hetao Irrigation District.This research also serves as a reference for future irrigation studies that consider measurements of both carbon emissions and yield simultaneously. 展开更多
关键词 carbon dioxide exchange maize growth drip irrigation harvest index net primary productivity Hetao Irrigation district
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Cutting-edge Technological Innovation Outcome Displayed at 2024 Beijing Science and Technology Week
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作者 Zhang Yida 《China's Foreign Trade》 2024年第3期47-49,共3页
The 2024 National Science and Technology Week and Beijing Science and Technology Week opened in Shougang Park in Shijingshan District from May 25 to June 1.Under the theme of“Carrying forward the spirit of scientists... The 2024 National Science and Technology Week and Beijing Science and Technology Week opened in Shougang Park in Shijingshan District from May 25 to June 1.Under the theme of“Carrying forward the spirit of scientists and inspiring societal innovation,”this event focused on the new-generation IT technology,medical health,energy and technology,modern agriculture and intelligent manufacturing industries. 展开更多
关键词 district CUTTING opened
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The Translation of Slangs in Two English Versions of Jin Ping Mei
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作者 ZHANG Yihong 《Cultural and Religious Studies》 2024年第3期146-157,共12页
The Chinese classical novel Jin Ping Mei abounds with a large number of slangs,which correspondingly leads to the difficulty of the novel’s English translation and also gives rise to the emergence of diversified Engl... The Chinese classical novel Jin Ping Mei abounds with a large number of slangs,which correspondingly leads to the difficulty of the novel’s English translation and also gives rise to the emergence of diversified English versions.The two English translators,Clement Egerton and David Roy,adopted completely different translation strategies when dealing with Chinese slangs in the novel.Their different translation purposes account for the significant disparity concerning the slang translation.Clement Egerton pays more attention to the novel’s plot in his English version The Golden Lotus,rather than the unique expressions of the original language,so that in the concrete translation process,a domestication strategy is adopted for the sake of the target language readers’understanding,resulting in distortion and omission of the slang expressions in the translated text.By contrast,the translation purpose which guides David Roy’translation The Plum in the Golden Vase is to convey the complexity and literariness of the original Chinese text,and hence the foreignization strategy is employed concerning slang translation,which aims to accurately reproduce the unique expressions of slangs in the original text.Comparatively speaking,David Roy’s translation succeeds in preserving the Chinese slangs to the greatest extent both in form and meaning,and can shed light for the slang translation in other Chinese literary works. 展开更多
关键词 jin Ping Mei SLANGS domestication and foreignization translation purpose
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A Study of the Treatment of Disfiguring Diseases in the “Qian Jin Fang”
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作者 Yuhan Li Yang Zhao 《Journal of Clinical and Nursing Research》 2024年第3期200-206,共7页
Traditional Chinese medicine(TCM)has been passed down for more than 2,000 years.TCM beauty products driven by the principles of identification and treatment with various dosage forms and exhibit mild and safe efficacy... Traditional Chinese medicine(TCM)has been passed down for more than 2,000 years.TCM beauty products driven by the principles of identification and treatment with various dosage forms and exhibit mild and safe efficacy are bound to become a main component of the beauty industry in the future.Xu once commented that“Qian Jin Fang”is different from the traditional prescription system,which emphasizes the use of medicines.In this paper,we mainly selected the prescriptions for the treatment of disfigurement diseases such as acne,scarring,black dryness,face hyperpigmentation,black mole,and rosacea from the article titled,“Upper Seven Orifices Disease-Facial Medicine IX”in the Bei Ji Qian Jin Yao Fang[1].By studying and analyzing the original composition of the formula,understanding the etiology and pathogenesis of the disease,and exploring the characteristics of the formula concerning the efficacy of TCM,their properties,flavors,and meridians,we summarized the characteristics of the Qian Jin Fang.It is based on the external treatment of disfigurement diseases,with a wide variety of drugs,flexibility,and accuracy.This method draws upon analogies while utilizing excipients and harmonizers to focus on the combined healing approach of treatment and nourishment. 展开更多
关键词 Qian jin fang External treatment Disfiguring diseases ACNE
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Epidemiological Characteristics of An Outbreak of Severe Acute Respiratory Syndrome in Dongcheng District of Beijing From March to May 2003 被引量:2
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作者 WAN—NIANLIANG‘ YONGHUANG +3 位作者 WAN—XINZHOU LEIQIAO JIAN—HuIHUANG ZHENG—LAIWU 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2003年第4期305-313,共9页
Objective To describe epidemiologic features of an outbreak of severe acute respiratory syndrome (SARS) in Dongcheng District, Beijing occurred in a period between March and May 2003. Methods Data of SARS cases notifi... Objective To describe epidemiologic features of an outbreak of severe acute respiratory syndrome (SARS) in Dongcheng District, Beijing occurred in a period between March and May 2003. Methods Data of SARS cases notified from Dongcheng District Center for Disease Control and Prevention (CDC )and supplemented by other channels were collected. Clinicians and officials of local hospitals were interviewed in groups and medical records of fatal cases of SARS were reviewed to verify the diagnosis. Stored serum specimens of the patients were detected for IgG antibody against SARS Co-V by enzyme-linked immunosorbent assay (ELISA). All the data were input into dataset files by Microsoft Excel-2000 software and analyzed with SPSS version 10.0 software. Results Outbreak of SARS in Dongcheng District started on March 14, 2003 with a peak in mid- and late April, and dropped in early May. A total of 572 reported cases were collected during this period in Dongcheng District, Beijing, and 99 of them were excluded from SARS, because of diagnosis of common cold, regular pneumonia, measles and rubella, etc. Actually, 473 SARS cases, which included 390 (82.5%) probable cases and 83 (17.5%) suspect cases, were analyzed. About 90% of the probable cases were positive for IgG antibody. Attack rate of SARS in permanent residents of Dongcheng District was 28.3 per 100 000. Forty-one of them died, with a case-fatality rate of 8.7%. Persons were all susceptible to infection of SARS Co-V, with the highest proportion at ages of 20-50 years, which accounted for 68.7% of the total cases. Average age of the patients at their onset was 40.7 years. No gender difference in SARS cases was found. Number of SARS cases in health-care workers (HCWs) accounted for 18.0% and that in retired workers accounted for 15.4% of the total cases. Cases occurred in all 10 sub-districts of Dongcheng, with the highest in Beixinqiao and Andingmen Sub-districts. Totally, 230 of the 572 notified cases (40.2%) were hospitalized at local hospitals under the jurisdiction of Dongcheng District. Eighteen of 85 cases of SARS occurred in HCWs of local hospitals, accounting for 4.5% of the total number of HCWs working at wards caring for SARS patients or fever clinics. There were 34.7% of SARS cases without any histories of contact before the onset of the disease. Familial aggregation phenomena were observed in 41.8% of the cases and 18.1% of households. And 7.4% (attack rate ) of those exposed to SARS cases suffered from the illness during the periods of quarantine. Conclusions SARS appeared to be infectious in origin and caused outbreak in Dongcheng District, Beijing introduced by an imported case traveling from Hong Kong in a period between March and May 2003. People are all susceptible to infection of SARS Co-V, which mainly threatens the young adults and the middle-aged, as well as HCWs and the retired workers. The main mode of transmission is direct exposure to SARS patients in a near distance at hospitals or families via droplets spread. Prevention and control of SARS should be focused on early isolation of patients and quarantine for close contacts. Current available measures to prevent and control SARS are proved to be effective. 展开更多
关键词 BEIjinG Dongcheng district OUTBREAK Severe acute respiratory syndrome (SARS) EPIDEMIOLOGY SARS coronavirus (SARS Co-V) Health-care workers (HCWs)
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Cause Analysis and Prediction of the Groundwater Level in Jinghuiqu Irrigation District 被引量:1
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作者 Wangxiong Tao Jie Zhang Jianying Wang 《Journal of Geoscience and Environment Protection》 2015年第2期85-89,共5页
Groundwater environment evolution can comprehensively reflect groundwater dynamics. Based on the relationship between the groundwater system and the external environment in Jinghuiqu irrigation district, adopting the ... Groundwater environment evolution can comprehensively reflect groundwater dynamics. Based on the relationship between the groundwater system and the external environment in Jinghuiqu irrigation district, adopting the Principal Component Analysis method, variation characteristics of environmental factors including climate and human activity and their impact on groundwater were systematically analyzed. The results show that groundwater level in Jinghuiqu irrigation district has been significantly dropped in nearly 34 years;the reduction of surface water irrigation use, which reduced the amounts of groundwater recharge and destroyed the water balance, is considered as the most direct cause for falling of regional groundwater level. Besides, reduction in precipitation, increase of evaporation also accelerated the declining of the groundwater level at some extent. Finally, a predicting method of groundwater depth based on BP neural network is developed. The experimental results show that the predicting model can reasonablely predict the groundwater level in Jinghuiqu irrigation district with a high precision. 展开更多
关键词 jinghuiqu IRRIGATION district GROUNDWATER Level CAUSE PREDICTION BP Neural Network
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Evaluation and Improvement Measures of Rural Human Settlements in Licheng District of Jinan City 被引量:1
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作者 Zhang Beibei Cui Dongxu 《Meteorological and Environmental Research》 CAS 2018年第2期39-46,共8页
Based on the data of rural human settlements in Licheng District of Jinan City in 2016,the evaluation system of rural human settlements composed of four subsystems( social economy,infrastructure,public environment,an... Based on the data of rural human settlements in Licheng District of Jinan City in 2016,the evaluation system of rural human settlements composed of four subsystems( social economy,infrastructure,public environment,and construction management) was constructed. According to the comprehensive scores of various administrative villages calculated by means of multi-index comprehensive evaluation method and fuzzy comprehensive evaluation method,the human settlements of 521 administrative villages in Licheng District were divided into four types: excellent,good,average,and poor. Moreover,the spatial differences in the evaluation results of rural human settlements were analyzed using GIS spatial analysis technology. Finally,based on the evaluation results of rural human settlements in Licheng District,some measures to improve and control rural human settlements in different types of villages at various development stages were proposed to fully improve the quality of rural human settlements. 展开更多
关键词 Rural human settlements EVALUATION Indicator system Classification guidance Licheng district
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The Current Situation and Planning Strategy of Police Station Facilities in Megacities Under the Background of New Urbanization:A Case Study of Changping District in Beijing 被引量:2
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作者 LI Daoyong LIU Junchen LIU Mengge 《Journal of Landscape Research》 2020年第3期47-53,共7页
In the process of new urbanization,the population of megacities is increasing rapidly,the scale of cities is expanding,and the supply of service facilities has been unable to meet the demand.As an important carrier of... In the process of new urbanization,the population of megacities is increasing rapidly,the scale of cities is expanding,and the supply of service facilities has been unable to meet the demand.As an important carrier of urban governance and urban management,the police station should properly deal with the existing problems in the urban police stations,and improve the quality of life of residents by optimizing urban service facilities,which is of great significance for the implementation of people-oriented new urbanization.Taking Changping District of Beijing as an example,this study pointed out that there were many problems in police stations in Changping District.For example,the area of land is not up to the standard,the service capacity is not up to the demand,and the facilities are not up to the demand.Then,three planning strategies:adjusting the planning standards of facilities,optimizing the spatial layout of facilities,and strengthening the later guarantee of facilities were put forward,so as to improve people’s satisfaction with life,promote the high-quality development of new urbanization,and provide reference for the supplement of service facilities in megacities. 展开更多
关键词 New urbanization MEGACITIES Police station Changping district
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Measurement and Spatial Distribution of Urban Land Use Compactness in Chaoyang District of Beijing,China 被引量:1
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作者 Hong Min Jin Fengjun Brian D. Fath 《Chinese Journal of Population,Resources and Environment》 2010年第4期3-9,共7页
China is in the process of rapid urbanization,and wise land use is critical to the long-term sustainability of Chinese cities.Promotion of a compact city is typically believed to be helpful for sustainable land use ma... China is in the process of rapid urbanization,and wise land use is critical to the long-term sustainability of Chinese cities.Promotion of a compact city is typically believed to be helpful for sustainable land use management.However,given the fact that Chinese cities are characterized by high population densities,the applicability of a more compact solution to expand cities in China remains questionable;there is little evidence to support the many claims in its favor.In seeking to provide empirical data to explore the application of compact city theory in China,one of the key problems researchers face is the task of measuring the urban compactness,in order to objectively investigate the current characteristics of urban compactness.To meet this need,indices were developed for measuring the urban land use compactness,by which the spatial distribution characteristics of urban land use compactness were identified and applied to the Chaoyang District of Beijing.The conclusions can be made as follows:(1) comprehensive land use compactness in Chaoyang District has increased during the period of 2001-2007,especially the population density;(2) the spatial distribution of land use compactness has the characteristics of a ring structure,which shows a decreasing trend with its distance to the city center;(3) there is a strong positive correlation between urban land use compactness and location.The better the location is,the higher the land use compactness is. 展开更多
关键词 urban land use compactness measurement indices Chaoyang district
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Molecular Epidemiological Analysis of Group A Streptococci Isolated from Children in Chaoyang District of Beijing, 2011:emm Types, Virulence Factor Genes and Erythromycin Resistant Genes 被引量:3
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作者 WANG Hai Bin SONG Yan Yan +4 位作者 YOU Yuan Hai WANG Heng Wei HAN Qin Hua ZHAO Jian Hong ZHANG Xiao Xi 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2013年第9期782-784,共3页
Group A streptococcus (GAS) causes a wide range of diseases in the human population. GAS diseases are more common in children than in adults, with clinical manifestations ranging from pharyngitis and impetigo to inv... Group A streptococcus (GAS) causes a wide range of diseases in the human population. GAS diseases are more common in children than in adults, with clinical manifestations ranging from pharyngitis and impetigo to invasive infections and post streptococcal sequelae, such as acute rheumatic fever and acute post-streptococcal glomerulonephritis[1]. GAS harbors a host of virulence factors that contribute to its complex pathogenicity and differences in the disease severity and frequency. M protein, one of the major virulence factors, is encoded by the emm gene induces a type of specific host immune response and confers antiphagocytic properties. 展开更多
关键词 Virulence Factor Genes and Erythromycin Resistant Genes emm Types Molecular Epidemiological Analysis of Group A Streptococci Isolated from Children in Chaoyang district of Beijing GAS
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Landscape Greening of Subway Stations Close to Commercial Districts in Beijing
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作者 WANG Ziyuan YANG Xin 《Journal of Landscape Research》 2019年第1期38-45,共8页
Due to the rapid urban construction, commercial districts in Beijing are constructed near subway stations. Good landscape greening plays a crucial role in improving the environmental quality of the area around subway ... Due to the rapid urban construction, commercial districts in Beijing are constructed near subway stations. Good landscape greening plays a crucial role in improving the environmental quality of the area around subway stations. At present, there are few studies on the landscape greening around subway stations adjacent to commercial districts. In this paper, field research on landscapes in the commercial district around seven typical subway stations was conducted to monitor real-time noise and crowd activities and analyze the utilization status of street parks, in order to provide a reference for the construction and renovation of the landscape greening around subway stations near commercial districts. 展开更多
关键词 Commercial district Area AROUND the SUBWAY STATION Noise LANDSCAPE GREENING
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Empirical Analysis on Dominant Agriculture in Agricultural Districts and Counties of Tianjin
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作者 Xiaolan YUN 《Asian Agricultural Research》 2017年第4期16-19,25,共5页
At present,developing the dominant agriculture plays an essential role in promoting the agricultural modernization of Tianjin. Based on the theory of location quotient,this paper made a quantitative analysis of the do... At present,developing the dominant agriculture plays an essential role in promoting the agricultural modernization of Tianjin. Based on the theory of location quotient,this paper made a quantitative analysis of the dominant agriculture in the agricultural districts and counties of Tianjin. According to the analysis,it made a qualitative analysis of the factors. Finally,it determined the dominant agriculture of each agricultural district and county of Tianjin. 展开更多
关键词 Agricultural districts and counties Dominant agriculture Empirical analysis TIANjin
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Numerical Simulation of Land Subsidence at Tanggu District in Tianjin, China 被引量:2
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作者 董国凤 张建军 +1 位作者 赵全 赵新华 《Transactions of Tianjin University》 EI CAS 2006年第6期457-462,共6页
Based on observed data from Tanggu District in Tianjin, a back-propagation neural network (BPNN) model was introduced to predict possible land subsidence due to exploitation of groundwater. According to model estimati... Based on observed data from Tanggu District in Tianjin, a back-propagation neural network (BPNN) model was introduced to predict possible land subsidence due to exploitation of groundwater. According to model estimation under various hypothetical extraction scenarios, patterns of land subsidence at Tanggu District were studied and discussed.The predicted average background land subsidence rate of Tanggu is 9.47 mm/a.The significance of contribution of aquifers to land subsidence descends in order of units Ⅳ,Ⅲ,Ⅴ,Ⅱ.Land subsidence tends to deteriorate with the increase in total extraction rate. 展开更多
关键词 地下水开采 承压含水层 地面沉降 神经网络 溏沽地区
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Land use scenarios simulation in ecological conservation area:A case study of Miyun district,Beijing
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作者 JIN Hao-ran LIU Sheng-he 《Ecological Economy》 2016年第2期102-111,共10页
Ecological conservation area,as the main water source and ecological barrier of a city,provides ecosystem service for urban sustainable development.Land use simulation and forecast could be beneficial to improve futur... Ecological conservation area,as the main water source and ecological barrier of a city,provides ecosystem service for urban sustainable development.Land use simulation and forecast could be beneficial to improve future land use efficiency and environmental protection.In this paper,we took the Miyun district as the study area and applied the CLUE-S model for land use simulation,based on land use data in 2001 and 2010.Eight key driving factors were selected,including elevation,slope,distance,population density and others.Based on the adjusted model parameters,the land use patterns of 2020 in Miyun district were simulated respectively for rapid growth scenario,land use planning scenario and ecological protection scenario and then identify the area needed extraordinary supervision in land planning implementation.The results showed that the simulation accuracy for 2010 reached 85%considerably,implying that the CLUE-S model is well fitted for modeling the land use pattern in Miyun district.Construction land increases and cultivated land decreases dramatically by 2020 in rapid growth and land use planning scenarios.The potential land use change tends to occur near Miyun reservoir,while the sensitive area for ecological protection and land planning implementation are distributed around urban area,Fengjiayu and Jugezhuang town.Some opencast mine areas,which would be converted to forest land in planning,will be hard to execute in the actual situation,so these areas should be paid more attention in land management.The conclusions made in this study will provide data reference and basic information for the future ecological protection and land use planning implementation in Miyun district,which could also be useful for other similar cities. 展开更多
关键词 land use simulation scenario analysis CLUE-S model Miyun district
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