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Impact mechanism of perception on the protection intention of tourist heritage sites:Taking the Hangzhou section of the Grand Canal as an example
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作者 GU Ya-qing LI A-jie 《Ecological Economy》 2024年第1期25-38,共14页
Heritage tourism is a hot research topic in the academic field,and most scholars focus on the development model of heritage tourism and heritage conservation theory and methods,but less on the heritage tourists themse... Heritage tourism is a hot research topic in the academic field,and most scholars focus on the development model of heritage tourism and heritage conservation theory and methods,but less on the heritage tourists themselves.Based on the theory of planned behavior,the study introduces the variable of“perception”,and takes the Hangzhou section of the Grand Canal as a case study,and investigates tourists through literature,fieldwork and questionnaires.The study constructs a“perception-subjective norm-willingness to protect”model to explore the influence of tourists’“perception”and“subjective norm”on“willingness to protect”.The study found that:first,heritage tourists’perceptions significantly affect attitudes,subjective norms,perceptual behavior control and willingness to conserve.Second,tourists’attitudes,subjective norms and perceptual behavior control significantly affect their willingness to conserve.Third,heritage tourists’economic perceptions,social perceptions and emotional perceptions can affect willingness to conserve.The study provides references for relevant governments and tourism enterprises to conserve and develop the Grand Canal section. 展开更多
关键词 heritage tourism the theory of planned behavior PERCEPTION willingness to protect
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Biogeochemistry of sedimentary organic matter in the Yongjiang River estuary in the southern part of Hangzhou Bay,China,since the Late Pleistocene
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作者 Dongqin HUANG Xiaolong LI +6 位作者 Zilong LI Pei Sun LOH Jianxiong HU Jianfang CHEN Yuan-Pin CHANG Chin-Wen YANG Qin GAO 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第3期772-786,共15页
A sediment core(YJK19-02)collected from the southern outlet of Hangzhou Bay near the Yongjiang River estuary in East China was analyzed for grain size,lignin,bulk elemental composition,stable carbon isotope,and rare e... A sediment core(YJK19-02)collected from the southern outlet of Hangzhou Bay near the Yongjiang River estuary in East China was analyzed for grain size,lignin,bulk elemental composition,stable carbon isotope,and rare earth elements(REEs)to determine the sources and diagenesis of sedimentary organic matter(OM)of the estuary and adjacent areas since the Late Pleistocene.δ^(13)C values(-24.80‰–-23.60‰),total organic carbon/total nitrogen(TOC/TN)molar ratios(8.00–12.14),and light rare earth element/heavy rare earth element ratios(LREE/HREE=8.34–8.91)revealed the predominance of terrestrial sources of OM,mainly from the Changjiang(Yangtze)River.The lignin parameters of syringyl/vanillyl(S/V=0.20–0.73)and cinnamyl/vanillyl(C/V=0.03–0.19)ratios indicate the predominance of nonwoody angiosperms,and the vanillic acid/vanillin ratios[(Ad/Al)_(V)=0.32–1.57]indicate medium to high degrees of lignin degradation.An increasing trend ofΛ(total lignin in mg/100-mg OC)values from ca.14500 a BP to ca.11000 a BP reflected the increase in temperature during the Late Pleistocene.However,a time lag effect of temperature on vegetation abundance was also revealed.The relatively higher and stableΛvalues correspond to the higher temperature during the mid-Holocene from ca.8500 a BP to ca.4500 a BP.Λvalues decreased from ca.4000 a BP to the present,corresponding to historical temperature fluctuations during this time.Our results show that the vegetation abundance in the Yongjiang River Basin since the Late Pleistocene was related to the temperature fluctuation duo to climate change. 展开更多
关键词 Yongjiang River estuary sedimentary organic matter LIGNIN environmental change Late Pleistocene
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Characterization of Mutations in Genes Related to Rifampicin and Isoniazid Resistance in Multidrug-resistant Mycobacterium tuberculosis Strains from Hangzhou,China
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作者 HUANG Yin Yan XIE Li +5 位作者 WU Yi Fei JIA Qing Jun CHENG Qing Lin LI Qing Chun AI Li Yun BAI Xue Xin 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2023年第9期869-873,共5页
Tuberculosis(TB),caused by the Mycobacterium tuberculosis complex(MTBC),is the 13^(th)leading cause of death and the second leading cause of infectious killer after COVID-19(above HIV and AIDS),according to the World ... Tuberculosis(TB),caused by the Mycobacterium tuberculosis complex(MTBC),is the 13^(th)leading cause of death and the second leading cause of infectious killer after COVID-19(above HIV and AIDS),according to the World Health Organization's 2022 Global TB Report.In 2021,10.6 million people were diagnosed with a new episode of TB and 1.6 million people died as a result. 展开更多
关键词 TUBERCULOSIS DEATH MYCOBACTERIUM
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Variation in reproductive life-history traits of Chinese Bulbuls(Pycnonotus sinensis)along the urbanization gradient in Hangzhou,China
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作者 Xingmin Chen Qin Zhang +3 位作者 Sisi Lan Qin Huang Shuihua Chen Yanping Wang 《Avian Research》 SCIE CSCD 2023年第2期174-181,共8页
Urbanization brings new selection pressures to wildlife living in cities,and changes in the life-history traits of urban species can reflect their responses to such pressures.To date,most of the studies investigating ... Urbanization brings new selection pressures to wildlife living in cities,and changes in the life-history traits of urban species can reflect their responses to such pressures.To date,most of the studies investigating the impacts of urbanization on avian life-history traits are conducted in Europe and North America,while such studies are often lacking in quickly developing countries in Asia(e.g.,China).In this study,we examined the variations in reproductive life-history traits of Chinese Bulbuls(Pycnonotus sinensis)along the urbanization gradient in Hangzhou,China.We detected 234 natural nests of Chinese Bulbuls and continuously monitored them in two continuous breeding seasons from 2012 to 2013.We collected data on seven life-history traits(laying date,incubation period,nestling period,clutch size,egg volume,hatching success rate,and fledging success rate).We used infrared cameras to record the number of feedings per hour as the measure of food resources for the nestlings.We measured nest predation pressure by monitoring 148 natural breeding nests during breeding seasons and 54 artificial nests immediately after breeding seasons.We then calculated the urbanization synthetic index(USI)as a measure of the level of urbanization and examined its relationship with the seven life-history traits.We found that Chinese Bulbuls laid eggs significantly earlier with increasing USI.However,the other six life-history traits did not vary significantly with the USI.Moreover,the feeding frequency of chicks increased significantly with the USI,but the nest predation pressure of Chinese Bulbuls decreased significantly with the USI.Increased food resources and reduced nest predation pressure in cities may lead to earlier laying date of Chinese Bulbuls.Further study should test whether the earlier laying date of Chinese Bulbuls is the result of phenotypic plasticity or genetic change. 展开更多
关键词 Feeding frequency Laying date Life-history trait Nest predation URBANIZATION Urbanization synthetic index(USI)
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Characteristics of Haze Weather and Its Meteorological In-fluencing Factors in Hangzhou
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作者 Yani ZHANG Rui LIU +2 位作者 Yunbiao ZHANG Yongliang HU Weishi AN 《Meteorological and Environmental Research》 CAS 2023年第1期24-28,共5页
Based on the observation data of the annual number of haze days,rainy days,fog days and gale days,sunshine hours,relative humidity and maximum wind speed at Hangzhou station from 1960 to 2021,the variation characteris... Based on the observation data of the annual number of haze days,rainy days,fog days and gale days,sunshine hours,relative humidity and maximum wind speed at Hangzhou station from 1960 to 2021,the variation characteristics of haze days and meteorological influencing factors were studied by mathematical statistical methods such as Mann-Kendall nonparametric test,sliding T test,wavelet analysis and Pearson correlation two-tailed test.The results show that the annual number of haze days generally showed an upward trend,and the climate tendency rate was 20 d/a;there was a sudden change around 2001,and it changed from stable to rapid growth;the number of haze days was the largest in spring and winter,followed by autumn,while it was the smallest in summer.The annual number of haze days had a strongly significant period of 40 a and a mesoscale variation period of 13 a.The number of haze days was negatively correlated with the number of rainy days,fog days and gale days,sunshine hours,relative humidity and maximum wind speed,which passed the 0.05 significance test.In recent 60 years,the number of rainy days and gale days,relative humidity,and maximum wind speed in Hangzhou have decreased,resulting in the weakening of atmospheric wet deposition capacity and power transmission conditions,which provided favorable meteorological conditions for the increase of haze weather. 展开更多
关键词 Number of haze days Wavelet analysis Influencing factor Correlation
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Short-term wind speed forecasting bias correction in the Hangzhou area of China based on a machine learning model
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作者 Yi Fang Yunfei Wu +4 位作者 Fengmin Wu Yan Yan Qi Liu Nian Liu Jiangjiang Xia 《Atmospheric and Oceanic Science Letters》 CSCD 2023年第4期37-44,共8页
准确的风速预报具有重要的社会意义.在本研究中,使用名为WSFBC-XGB的XGBoost机器学习模型对中国浙江省杭州市自动气象站的短期风速预报误差进行校正.WSFBC-XGB使用本地数值天气预报系统的产品作为输入.将WSFBC-XGB校正的结果与传统MOS(... 准确的风速预报具有重要的社会意义.在本研究中,使用名为WSFBC-XGB的XGBoost机器学习模型对中国浙江省杭州市自动气象站的短期风速预报误差进行校正.WSFBC-XGB使用本地数值天气预报系统的产品作为输入.将WSFBC-XGB校正的结果与传统MOS(模型输出统计)方法校正的结果进行了比较.结果表明:WSFBC-XGB预报风速的均方根误差(RMSE)/准确率(ACC)分别比NWP和MOS降低/提高了26.1%和7.64%/35.6%和7.02%;对于90%的站点WSFBC-XGB的RMSE/ACC均小于/高于MOS.此外,采用平均杂质减少法对WSFBC-XGB的可解释性进行分析,以帮助用户增加对模型的信任.结果表明:10米风速(47.35%),10米风的经向分量(12.73%),日循环(9.97%)和1000百帕风的经向分量(7.45%)是前4个最重要的特征.WSFBC-XGB模型将有助于提高短期风速预报的准确性,为大型户外活动提供支持. 展开更多
关键词 机器学习 极端梯度提升算法 风速 后处理 平均杂质减少
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Distribution pattern of macrobenthic assemblages along a salinity gradient in the Hangzhou Bay and its adjacent waters
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作者 Runxuan Yan Xiaobo Wang +1 位作者 Songyao Peng Qingxi Han 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第9期79-89,共11页
It is widely acknowledged that the distribution of macrobenthos is affected by salinity, but the degree of influence varies in different areas. To explore the distribution pattern of macrobenthic assemblages in the Ha... It is widely acknowledged that the distribution of macrobenthos is affected by salinity, but the degree of influence varies in different areas. To explore the distribution pattern of macrobenthic assemblages in the Hangzhou Bay,12 stations were sampled to collect macrobenthos and the corresponding bottom water. Changes in the general characteristics of macrobenthos along the salinity gradient in the Hangzhou Bay and its adjacent waters were considered. Three dominant species were identified, including the polychaetes Sternaspis chinensis, the crustacea Oratosquilla oratoria and the echinoderm Ophiuroglypha kinbergi. And the macrobenthic assemblages showed a zonal distribution along with the salinity change. The correlation analyses showed that salinity, depth,temperature, suspended solids and dissolved oxygen had concurrent significant correlations with carnivorous group, Margalef species richness(d), Brillouin index(H) and Shannon-Wiener diversity index(H'). In light of the strong correlation between salinity and Changjiang River diluted water, which produces considerable disturbances by freshwater inflows, the deposition of suspended solids and the resuspension of seabed sediments,the combined environmental disturbances, instead of salinity alone, should be adopted to explain the zonation distribution pattern of macrobenthic assemblages. 展开更多
关键词 MACROBENTHOS dominant species functional groups environmental disturbances
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Impact of Land Use Change on Vegetation Carbon Storage During Rapid Urbanization:A Case Study of Hangzhou,China 被引量:4
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作者 WANG Zhi XU Lihua +6 位作者 SHI Yijun MA Qiwei WU Yaqi LU Zhangwei MAO Liwei PANG Enqi ZHANG Qi 《Chinese Geographical Science》 SCIE CSCD 2021年第2期209-222,共14页
Land use changes have significant impacts on the carbon balance in an urban ecosystem.When there is rapid development in urbanizing regions,land use changes have a dramatic effect on vegetation carbon storage(VCS).Thi... Land use changes have significant impacts on the carbon balance in an urban ecosystem.When there is rapid development in urbanizing regions,land use changes have a dramatic effect on vegetation carbon storage(VCS).This study investigates the impact of land use change on VCS in a period of rapid urbanization in Hangzhou,China.The results show that:1)from 2000 to 2015,land use in Hangzhou underwent huge changes,mainly reflected in decrease in cropland and wetland and the increased settlement.More than 34.58%of the land was transformed,and the land use changes are primarily characterized by a significant decrease in cropland due to the occupation by settlement.2)over the 15 years,changes in land use led to a decrease of 3.93×10^(5) t of VCS in the urban ecosystem.The large-scale transformation of cropland and wetland,which have a comparatively high carbon density,into land for settlement exerted a negative impact on VCS.3)The central city,which with the Circle-E/I/O mode,had the lowest comprehensive land use dynamic degree,leading to moderate land use change and an increase in VCS;Yuhang and Xiaoshan,which with Multicore-E/O/I mode and Fan-E/O/I modes,had a higher comprehensive land use dynamic degree,drastic changes in land use,and a decrease in VCS.This study proposes a reliable method of estimating changes in VCS,clarifies the relationship between land use change and VCS during rapid urbanization,and provides recommendations for sustainable urban development. 展开更多
关键词 land use change vegetation carbon storage(VCS) URBANIZATION GAIN-LOSS method Hangzhou China
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Molecular Characterization and Correlation with β-lactam Resistance of Streptococcus pneumonia Isolates in Hangzhou,China 被引量:7
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作者 chu mei fen liu xiao xiang +6 位作者 zhang shao ni huang yan ying du peng wang li fang ji lei yan jie sun ai hua 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2018年第5期389-393,共5页
Penicillin-binding proteins(PBPs) are the target of β-lactam antibiotics(the major treatment for Streptococcus pneumoniae infections),and mutations in PBPs are considered as a primary mechanism for the developmen... Penicillin-binding proteins(PBPs) are the target of β-lactam antibiotics(the major treatment for Streptococcus pneumoniae infections),and mutations in PBPs are considered as a primary mechanism for the development of β-lactam resistance in S.pneumoniae.This study was conducted to investigate the mutations in the PBPs of clinical S.pneumoniae isolates in Hangzhou,China,in correlation with β-lactam resistance.Results showed that 19 F was the predominant serotype(7/27) and 14 of the S.pneumoniae isolates were resistant to both penicillin G and cephalosporin.Genotyping results suggested that β-lactam-resistant isolates primarily exhibited single-site mutations in both the STMK and SRNVP motifs of pbp1 a in combination with double-site mutations in the STMK motif of pbp2 x,which might be the primary mechanisms underlying the β-lactam resistance of the isolates in this study. 展开更多
关键词 PBP lactam Resistance of Streptococcus pneumonia Isolates in Hangzhou China RSP
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Impact of economic development on wetlands in Hangzhou Bay Industrial Belt 被引量:4
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作者 REN Liyan YUE Wenze +1 位作者 LI Jialin WU Cifang 《Journal of Geographical Sciences》 SCIE CSCD 2010年第3期406-416,共11页
Based on Landsat TM images in 2005 and urban planning data of 2005-2020 in Hangzhou Bay Industrial Belt, this paper studied the potential risk of the planned urban construction land extension to the wetlands by employ... Based on Landsat TM images in 2005 and urban planning data of 2005-2020 in Hangzhou Bay Industrial Belt, this paper studied the potential risk of the planned urban construction land extension to the wetlands by employing a GIS spatial analysis method. The results show that: (1) The wetland resources are widely distributed and diverse, with a proximal distribution to present urban construction lands spatially. (2) From 2005 to 2020, the urban construction lands will expand vastly and rapidly, and will take over large areas of wetlands that are mostly the ponds and the aquiculture water areas in the reclamation areas of Hangzhou Bay south coast. Moreover, this change will be spatially uneven obviously, e.g., the most serious recessions of the wetlands are concentrated in Ningbo city, Hangzhou city and Cixi city. (3) Overall, the potential risk to wetlands is very high, and will keep increasing with the trend of urbanization. (4) The quantity and spatial pattern of the planning urban construction land have substantial impacts on the wetland loss. Therefore, some policies and regulations are suggested to coordinate the relationship between urban economic development and wetland resource protection such as adjusting the construction land planning, compensating for wetland occupation as well as constructing wetland parks. 展开更多
关键词 WETLANDS change prediction risk analysis urban planning Hangzhou Bay Industrial Belt (HBIB)
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The Distribution of Sedimentary Organic Matter and Implication of Its Transfer from Changjiang Estuary to Hangzhou Bay, China 被引量:3
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作者 Fanglu Xu Zhongqiang Ji +2 位作者 Kui Wang Haiyan Jin Pei Sun Loh 《Open Journal of Marine Science》 2016年第1期103-114,共12页
In this study, a comparison was made between the Changjiang Estuary and the Hanghzou Bay, in terms of the sources and diagenesis of the sedimentary organic matter (OM). To achieve this purpose, surface sediments from ... In this study, a comparison was made between the Changjiang Estuary and the Hanghzou Bay, in terms of the sources and diagenesis of the sedimentary organic matter (OM). To achieve this purpose, surface sediments from the estuary and bay were analyzed for lignin-derived phenols, stable carbon isotope and TOC/TN (total organic carbon/total nitrogen) molar ratio. The signal of land-derived OM decreased, and the vanillic acid to vanillin ratio, (Ad/Al)v, increased with increasing distance from the Changjiang Estuary and the Hangzhou Bay. These results corresponded with the contribution of the terrigenous OM from the rivers to the coastal zone, and the predominance of marine OM farther offshore, and that the land-derived OM underwent decomposition during transport along the estuary and bay. It should be noted that besides the Qiantang River, Hangzhou Bay is also receiving more than half of its materials from Changjiang Estuary, which flows into the Hangzhou Bay at the north, and leaves via the southern part of the bay. This important aspect of the hydrological cycle in Hangzhou Bay corresponded to higher Λ (total lignin in mg/100 mg OC), higher TOC and C/N ratios and more elevated (Ad/Al)v and (Ad/Al)s values in the bay than the Changjiang Estuary, thus, rendering the bay as a site for the accumulation and rapid cycling of terrigenous OM. 展开更多
关键词 Changjiang Estuary Hangzhou Bay Sedimentary Organic Matter LIGNIN
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International Silica Cycle Workshop held in Hangzhou
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作者 TREGUER Paul RAN Lihua +1 位作者 CHAI Fei CHEN Jianfang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2018年第12期129-129,共1页
Silicon is the second most abundant element on the planet Earth. Its electronic configuration is close to that of carbon, but the aqueous environment prevailing on our planet gives advantages to carbon compounds at th... Silicon is the second most abundant element on the planet Earth. Its electronic configuration is close to that of carbon, but the aqueous environment prevailing on our planet gives advantages to carbon compounds at the expenses of siliceous compounds.Silicified organisms, however, are everywhere on Earth, particularly in the marine realm where siliceous diatoms play a key role in the ocean biological carbon pump. Thus, a better understanding of the processes that control the silica cycle at global scale is crucial. 展开更多
关键词 Hangzhou INTERNATIONAL SYMPOSIUM on silicon RECYCLING carbon
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Occurrence Regularity and Prediction Model of Underground Pest Adults in Hangzhou District of China
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作者 Wang Daoze Hong Wenying +2 位作者 Wu Yanjun Wang Aijuan Wei Jiqian 《Plant Diseases and Pests》 CAS 2013年第1期1-6,27,共7页
To improve forecasting and sustained control level of underground pests, trapping quantity of underground pests (black cutworm,mole cricket and scar-ab) by lamps and their field dynamics in Hangzhou district from 20... To improve forecasting and sustained control level of underground pests, trapping quantity of underground pests (black cutworm,mole cricket and scar-ab) by lamps and their field dynamics in Hangzhou district from 2005 to 2011 were investigated in the paper. The results showed that different pests had obvious differences in population dynamic. The black cutworm (Agrotis ypsilon) had several damage peaks (late May, late June and late July) and the moth amount in early period was relatively high. The mole cricket ( Gryllotalpa africana) had two damage peaks (late May to early July, early September to mid and late October). The scarab (Anomala corpulenta) had one damage peak (late May to late June). There were periodic changes in total quantity of underground pests among years, and the peak period appeared in the year of 2005, 2007 to 2009 and 2011, respectively. On this basis, temperature, humidity, rainfall and light were used as forecas- ting factors, using the method of stepwise regression, 19 factors with significant correlation were screened out and prediction models for occurrence quantity and oc- currence period of the three pests were established. By using accuracy degree judge model for verification, the score values of prediction model for occurrence quan-tity and occurrence period of the three underground pests were more than 58 and 70, which indicated that the historical coincident rate and prediction accuracy of estabhshed prediction models were good. 展开更多
关键词 Hangzhou district Underground pests Population dynamic Occurrence regularity Prediction model
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Soundscape evaluation and integrated humanist ecology of audiovisual sense in Hangzhou Gongshu section of the Beijing-Hangzhou Grand Canal
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作者 SHI Jian-ren JIN Shu-min YANG Yi 《Ecological Economy》 2022年第3期225-230,共6页
Located at the end of the Beijing-Hangzhou Canal,Hangzhou has a historical and cultural heritage with an abundance of acoustic and visual landscape.The paper introduces the concept of“soundscape”into the canal lands... Located at the end of the Beijing-Hangzhou Canal,Hangzhou has a historical and cultural heritage with an abundance of acoustic and visual landscape.The paper introduces the concept of“soundscape”into the canal landscape design,and analyzes its characteristics through documentary analysis,questionnaire method,soundscape walk method,grid method and statistical analysis method.Besides,GIS is also used to present the analysis in a visualized way.The study adopt the increase,decrease and protect design methods which are commonly used in soundscape and the landscape combination methods derived from the classic landscape rules.Eventually,the design is performed in a targeted manner from the perspective of the integrated design of vision and soundscape,offering a optimum proposal and construction strategy.It is hoped that it can promote the design of the integrated acoustic-visual environment of the canal so as to improve the overall spatial environment quality of the urban canal. 展开更多
关键词 SOUNDSCAPE integrated design of vision and soundscape soundscape map the Beijing-Hangzhou Canal
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Research on the Traveling Characteristics and Comparison of Bike Sharing in College Campus-A Case Study in Hangzhou
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作者 Yang Tang Weiwei Liu +3 位作者 Chennan Zhang Yihao He Ning Ji Xinyao Chen 《Journal on Internet of Things》 2020年第3期89-99,共11页
Bike sharing emerging from college campus in China's Mainland has become a major part in the daily traveling of Chinese urban residents.It changes the traveling behavior of urban residents,and simultaneously,raise... Bike sharing emerging from college campus in China's Mainland has become a major part in the daily traveling of Chinese urban residents.It changes the traveling behavior of urban residents,and simultaneously,raises higher requirements on urban transportation facility construction and management.However,the return of bike sharing to college campus causes more troubles to schools.The fundamental cause is the closed peculiarity of campus traveling comparing with city traveling,and also the discrepancy between college campuses of different types.This paper investigates the traveling characteristics of bike sharing in college campus in three different locations in Hangzhou City,Zhejiang Province of China in the questionnaire,and compares the discrepancy with urban bike sharing traveling characteristics and the discrepancy in bike sharing use between college campuses of different types.From the perspective of parking,maintenance and operation,and hardware design,the paper eventually raises suggestions to optimize independent college campus bike sharing service facility and management consistent with urban system.The research may also offer beneficial reference to the release of bike sharing facilities consistent with urban system in all sorts of independent parks,especially college campus. 展开更多
关键词 Bike Sharing university campus travel characteristics Hangzhou
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A survey on porcine circovirus type 2 infection and phylogenetic analysis of its ORF2 gene in Hangzhou,Zhejiang Province,China 被引量:13
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作者 Zong-zhao YANG Jiang-bing SHUAI +1 位作者 Xian-jun DAI Wei-huan FANG 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2008年第2期148-153,共6页
Porcine circovirus type 2 (PCV2) is closely related to the postweaning multisystemic wasting syndrome (PMWS). In this study, the pig serum and tissue samples collected from different regions of Hangzhou District in Zh... Porcine circovirus type 2 (PCV2) is closely related to the postweaning multisystemic wasting syndrome (PMWS). In this study, the pig serum and tissue samples collected from different regions of Hangzhou District in Zhejiang Province of China between 2003 and 2005 were analyzed by enzyme-linked immunosorbent assay (ELISA) for PCV2 antibody and by polymerase chain reaction (PCR) for ORF2 gene. The results show that out of 1250 randomly collected serum samples, 500 sera (40%) were seropositive for PCV2. PCR results demonstrate that Hangzhou PCV2 with more than 50% Chinese PCV2 strains and French PCV2 formed Cluster A. Only one PCV2 from Hangzhou belonged to Cluster B with some other Chinese PCV2 and Netherlands’s isolates. Cluster C consisted of PCV2 isolates from China, US, Canada, UK and Germany. The results indicate that the PCV2 infection was widespread in Hangzhou. 展开更多
关键词 PCV2 动植物分析 遗传基因 中国
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Heavy Metals, Phosphorus and Some Other Elements in Urban Soils of Hangzhou City, China 被引量:93
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作者 ZHANGMing-Kui KEZi-Xia 《Pedosphere》 SCIE CAS CSCD 2004年第2期177-185,共9页
Health implications of inhaling and/or ingesting dust particles with high concentrations of heavy metals from urban soils are a subject of intense concern. Understanding the geochemistry of these metals is key to thei... Health implications of inhaling and/or ingesting dust particles with high concentrations of heavy metals from urban soils are a subject of intense concern. Understanding the geochemistry of these metals is key to their effective management. Total concentrations of heavy metals,phosphorus (P) and 8 other elements from topsoil samples collected at 82 locations in Hangzhou City were measured to:a) assess their distribution in urban environments; and b) understand their differentiation as related to land use. Metal mobility was also studied using a three-step sequential chemical fractionation procedure. About 8.5%,1.2%,3.6%,11.0% and 30.3% of the soil samples had Cd,Cr,Cu,Pb,and Zn concentrations,respectively,above their allowable limits for public and private green areas and residential use. However,in commercial and industrial areas,most samples had metal concentrations below their allowable limits. Statistical analyses revealed that the 16 measured elements in urban soils could be divided into four groups based on natural or anthropic sources using a hierarchical cluster analysis. Additionally,Cu,Pb,and P showed similar spatial distributions with significant pollution in commercial zones,suggesting vehicle traffic or commercial activities as dominant pollutant sources. Also,Cd,Co,Cr,Ni,Zn,Mn and Fe had the highest concentrations in industrial locations,signifying that industrial activities were the main sources of these seven metals. Moreover,the data highlighted land-use as a major influence on heavy metal concentrations and forms found in topsoils with large proportions of soil Cd,Co,Cr,and Ni found in residual fractions and soil Cu,Pb and Zn mainly as extractable fractions. 展开更多
关键词 重金属 城市土壤 杭州
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PAHs in aquatic sediment in Hangzhou, China: Analytical methods, pollution pattern, risk assessment and sources 被引量:15
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作者 ZHU Li-zhong CAI Xue-fen WANG Jing 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第5期748-755,共8页
Eleven surface sediment samples, from Hangzhou section of Qiantang River and Jinghang Canal, west Lake the inland river were collected to investigate 17 polycycUc aromatic hydrocarbons(PAHs) pollution in aquatic sed... Eleven surface sediment samples, from Hangzhou section of Qiantang River and Jinghang Canal, west Lake the inland river were collected to investigate 17 polycycUc aromatic hydrocarbons(PAHs) pollution in aquatic sediments of Hangzhou. Accelerated solvent extraction(ASE) was used to extract PAHs from sediments with satisfactory recoveries. It was found that the total PAHs in the sediments ranged from 308.4 to 3037 ng/g dw, and PAHs pollution in sediments from Jinghang Canal were the heaviest. Lowest effect level(LEL) and severe effect level (SEL) sediment quality guidelines were introduced to perform risk assessment for PAHs pollution in aquatic sediments. Only one sample in Jinghang Canal had adverse impact on benthic organism. 2-3 ring PAHs had a noticeable contribution to total PAHs, especially NA, PHEN. A quantity method was used to determine the major source, the results showed petroleum origin was the chief source to PAHs pollution in all sediments with the exception of sediments from Jinghang Canal where combustion sources had a larger contribution. 展开更多
关键词 PAHS ASE SEDIMENT source risk assessment
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Concentrations and chemical forms of potentially toxic metals in road-deposited sediments from different zones of Hangzhou, China 被引量:22
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作者 ZHANG Mingkui WANG Hao 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第5期625-631,共7页
The 25 road-deposited sediments were collected from five different land-use zones (industrial, residential, commercial, park, and countryside) in Hangzhou, China. The concentrations of metals (Cd, Co, Cr, Cu, Fe, M... The 25 road-deposited sediments were collected from five different land-use zones (industrial, residential, commercial, park, and countryside) in Hangzhou, China. The concentrations of metals (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) in these samples were determined using ICP-AES after digestion with the mixture of HNO3-HF-HC1 (aqua regia), and chemically fractionated according to the modified BCR (the European Community Bureau of Reference) sequential extraction procedure. The high metal concentration levels were detected in the sample from industrial zone and commercial zone having heavy traffic. While the low metal levels were noted in the street dust sample from residential zone, park, and countryside zone. The mobility sequence based on the sum of the BCR sequential extraction stages was: Zn (80.28%), Pb (78.68%), Cd (77.66%) 〉 Cu (73.34%) 〉 Mn (67.92%) 〉 Co (41.66%) 〉 Ni (30.36%) 〉 Cr (21.56%), Fe (20.86%). Correlation analysis and principal component analysis were applied to the data matrix to evaluate the analytical results and to identify the possible pollution sources of metals. Factor analysis showed that these areas were mainly contaminated by three sources, namely lithology, traffic, and industry. 展开更多
关键词 heavy metals road-deposited sediment BCR sequential extraction multivariate analysis
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Post-transplant diabetes mellitus in liver transplantation:Hangzhou experience 被引量:21
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作者 Xu, Xiao Ling, Qi +2 位作者 He, Zeng-Lei Gao, Feng Zheng, Shu-Sen 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2008年第5期465-470,共6页
BACKGROUND: Diabetes mellitus (DM) is a frequent and serious complication in patients with liver diseases. We aimed to assess the prevalence and consequences of post-transplant DM (PTDM) in Chinese patients with HBV-r... BACKGROUND: Diabetes mellitus (DM) is a frequent and serious complication in patients with liver diseases. We aimed to assess the prevalence and consequences of post-transplant DM (PTDM) in Chinese patients with HBV-related liver diseases and to determine the possible risk factors. METHODS: Altogether 165 patients with HBV infection and undergoing cadaveric related liver transplantation (LT) were enrolled. The clinical data of patients with (PTDM group) and without PTDM (non-PTDM group) were compared. RESULTS: Of the 165 patients, 28 had DM and 12 had impaired fasting glucose (IFG) before LT. Patients with pre-transplant DM or IFG had a survival rate similar to that of the others. Forty patients (24.2%) developed PTDM with a mean time of 36 17 days (range 2-300 days) after LT. Of those, 32 developed PTDM within 3 months post-LT and 29 needed insulin treatment. Pre-transplant hepatic encephalopathy and tacrolimus application were found more frequently in the PTDM group than in the non-PTDM group. The plasma tacrolimus levels were notably higher at I and 3 months post-LT in the PTDM group than those in the non-PTDM group. Compared to the non-PTDM group, the PTDM group showed remarkably poorer survival and tumor-free survival in patients with hepatocellular carcinoma, and significantly higher incidence of sepsis, fungal infection, chronic kidney diseases and biliary complications after LT. CONCLUSIONS: Pre-transplant DM did not affect the patient survival after LT. Since PTDM is common, it has a negative impact on outcome and may contribute to tumor recurrence. Pre-transplant hepatic encephalopathy, a tacrolimus-based regimen, and high levels of tacrolimus are clearly associated with the occurrence of PTDM. 展开更多
关键词 diabetes mellitus hepatitis B virus liver transplantation PROGNOSIS
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