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Status quo and trend of development of comprehensive resource utilization of citrus by-products
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作者 Yuan Hu Hanxi Li +2 位作者 Keming Yin Jun Chen Fu Wang 《Journal of Future Foods》 2026年第6期1084-1102,共19页
Citrus is the world's most produced fruit.With the rapid growth of citrus cultivation and processing industries globally,the volume of by-products,including dropped fruits,defective fruits,and waste generated duri... Citrus is the world's most produced fruit.With the rapid growth of citrus cultivation and processing industries globally,the volume of by-products,including dropped fruits,defective fruits,and waste generated during processing,has surged.Consequently,resource wastage and environmental pollution due to the low utilization rate of these by-products have become increasingly prominent issues.Currently,citrus by-products are directly utilized as seasonings,tea,and traditional Chinese medicine,or for the extraction of pectin,flavonoids,carotenoids,limonoids,essential oils,synephrine,and other functional ingredients.They are also processed into ethanol,citric acid,feed,and organic fertilizer through biomass fermentation.Despite these applications,the overall utilization rate of citrus by-products remains low.Additionally,there is a lack of key technologies and core equipment,and the production of high value-added functional products is limited.The future direction for citrus by-product utilization lies in green,low-carbon,high-efficiency,and high-value comprehensive recycling.To address the serious environmental pollution and recycling challenges posed by citrus rotting,it is proposed for the first time to develop new products and mold prevention strategies throughout the entire citrus supply chain-"Planting-field management-harvesting-transportation-storage"-to achieve a circular economy approach.This strategy aims to"Take from citrus and give back to citrus"effectively preventing and reducing citrus rotting.Furthermore,it can mitigate the significant economic losses caused by fruit decay and provide insights into the high-quality development of comprehensive citrus by-product utilization. 展开更多
关键词 CITRUS By-products RECYCLING Low-carbon utilization High-value utilization Mold prevention strategy
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Large-scale modelling wind damage vulnerability through combination of high-resolution forest resources maps and ForestGALES
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作者 Morgane Merlin Tommaso Locatelli +1 位作者 Barry Gardiner Rasmus Astrup 《Forest Ecosystems》 2025年第5期1021-1034,共14页
Assessing forest vulnerability to disturbances at a high spatial resolution and for regional and national scales has become attainable with the combination of remote sensing-derived high-resolution forest maps and mec... Assessing forest vulnerability to disturbances at a high spatial resolution and for regional and national scales has become attainable with the combination of remote sensing-derived high-resolution forest maps and mechanistic risk models. This study demonstrated large-scale and high-resolution modelling of wind damage vulnerability in Norway. The hybrid mechanistic wind damage model, ForestGALES, was adapted to map the critical wind speeds(CWS) of damage across Norway using a national forest attribute map at a 16 m × 16 m spatial resolution. P arametrization of the model for the Norwegian context was done using the literature and the National Forest Inventory data. This new parametrization of the model for Norwegian forests yielded estimates of CWS significantly different from the default parametrization. Both parametrizations fell short of providing acceptable discrimination of the damaged area following the storm of November 19, 2021 in the central southern region of Norway when using unadjusted CWS. After adjusting the CWS and the storm wind speeds by a constant factor, the Norwegian parametrization provided acceptable discrimination and was thus defined as suitable to use in future studies, despite the lack of field-and laboratory experiments to directly derive parameters for Norwegian forests. The windstorm event used for model validation in this study highlighted the challenges of predicting wind damage to forests in landscapes with complex topography. Future studies should focus on further developing ForestGALES and new datasets describing extreme wind climates to better represent the wind and tree interactions in complex topography, and predict the level of risk in order to develop local climate-smart forest management strategies. 展开更多
关键词 WIND Natural disturbance ForestGALES Damage probability Forest resource map
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Integrated Water Resource Assessment of Irrigation System of Haryana
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作者 Shiv Singh Rawat S. Lahari A. K. Gosain 《Agricultural Sciences》 2018年第4期489-510,共22页
Agriculture is the major activity in the state of Haryana and large volume of water is required to meet the irrigation demands of the crops grown. But, there is limited water availability in the state. Haryana receive... Agriculture is the major activity in the state of Haryana and large volume of water is required to meet the irrigation demands of the crops grown. But, there is limited water availability in the state. Haryana receives water from Yamuna River and Bhakra system. Sowmelt, rainfall and groundwater are main sources of water in the catchment. It is essential to integrate the manmade canal system with hydrological system. This paper focuses on integrated hydrological modeling framework to conceptualize the system and to assess the Water Resources of the state. Snowmelt and Rainfall runoff modeling using GR4JSG model were combined to model the inflows to the irrigation system of Haryana. Irrigator canal model of eWater Source has been used to generate water demands from crops grown. The water balance and water use efficiency have been worked out for each district of Haryana. The hydro climate input data, stream flows, crop data and soil data have been used in the study. The flows modeled at Tuini (P), Yashwant Nagar, Bausan, Haripur, Poanta and HKB sites were compared with the observed flows. The objective function of NSE Daily and log Flow duration was used for model calibration and validation at various locations up to Mathura, the outlet of the study area. The value of the objective function at Mathura was 0.54, a fairly good value. The results of the Irrigator canal model have shown that all the Inflows, Outflows and the Utilizations of water have been properly balanced for each district. The water use efficiency of districts varies from 27% to 59%. The overall water use efficiency for Haryana canal system has been calculated as 39%. This is low value indicating excess water is being extracted to meet the water demands. 展开更多
关键词 HYDROLOGICAL Modeling GR4JSG MODEL GR4J MODEL MODIS Snow Cover IRRIGATOR CANAL MODEL eWater Source WATER Balance and WATER Use Efficiency
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Economic Sustainability Assessment of Groundwater Resources: Case Study of Hanoi, Vietnam
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作者 Nuong Thi Bui Akira Kawamura +3 位作者 Hideo Amaguchi Duong Du Bui Ngoc Tu Truong Hoang Nam Nguyen 《Journal of Environmental Science and Engineering(B)》 2017年第12期624-633,共10页
The most useful indicators should be established, designed and customized based on local issues of a target area. In order to establish groundwater sustainability indicators for the Vietnam capital, Hanoi, in this stu... The most useful indicators should be established, designed and customized based on local issues of a target area. In order to establish groundwater sustainability indicators for the Vietnam capital, Hanoi, in this study, the sustainability assessment framework of groundwater resources from an economic perspective is proposed for the first time with the focus of Hanoi current groundwater problems. An AHP (Analytical Hierarchy Process) approach is employed to generate the main components (aspects and indicators) of this framework, because development of composite indicators is considered to be a best approach for sustainability evaluation. To do this, the current problems of Hanoi groundwater resources were carefully reviewed and explored to propose three main aspects (quantity, quality and management) and appropriately construct their 9 MESIs (Macroeconomic Sustainability Indicators). As for the results, the sustainability indices of the quantity, quality and management aspects were appropriately assessed as good, excellent and good sustainability levels, respectively. As a result, the sustainability of Hanoi groundwater resources development is economically good, indicating that there has been a big effort to improve the groundwater sustainability from both sides, the local government and communities. 展开更多
关键词 GROUNDWATER MESI sustainability assessment AHP Hanoi.
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Structural Stability and Accumulation of Organic Matter in Some Soils under Cashew Tree Orchards in the Department of Touba in North-West Cote d’Ivoire
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作者 Alui Konan Alphonse Ballo Koffi Celestin +1 位作者 Kouassi Kouakou Joselin Yao-Kouame Albert 《Open Journal of Soil Science》 2020年第5期181-193,共13页
Degradation of the physical quality of the soil is a common problem encountered in agrosystems, particularly in the case of open field cropping systems in the northern areas of C&#244;te d’Ivoire. Thus, the struc... Degradation of the physical quality of the soil is a common problem encountered in agrosystems, particularly in the case of open field cropping systems in the northern areas of C&#244;te d’Ivoire. Thus, the structural stability of the soil, which is a good indicator of the sensitivity to threshing and to water erosion in relation to the accumulation of organic matter, was evaluated in two types of soil (Ferralsol and Cambisol) in cashew orchards, in two villages (Mahana and Sanankoro) producing cashew nuts, located the Department of Touba in the North West of C&#244;te d’Ivoire. The objective of this study is to develop new technical routes that are better suited to further promote the sequestration of organic carbon in the soil. Soil samples were taken from open soil profiles at the two chosen sites to allow laboratory analyzes. The results indicate that the surface horizon of Cambisol (site 1) is more stable (Is = 0.78) than that of Ferralsol (site 2;Is = 1.08) with nevertheless relatively small thicknesses of horizons. The median horizons and those of depth, indicate a mediocre stability (Is vary from 1.03 to 1.62). In terms of the quantity of organic carbon, the estimated values vary from 1.96 to 4.53 t&sdot;ha&minus;1 for Cambisol (site 1) and from 1.44 to 3.46 t&sdot;ha&minus;1 for Ferralsol (site 2). These values remain relatively low especially at the level of the median horizons and those located in depths. Statistical tests have shown a very highly significant and negative association between the structural stability of soils and the amount of organic carbon in the different horizons. The relationship implies that organic carbon plays an important role in the structural stability of soil horizons under cashew tree orchards. 展开更多
关键词 Structural Stability Organic Carbon SOILS CASHEW Cote d’Ivoire
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Underground mining impact on groundwater in Kuye River Basin,China:A coupling model study 被引量:1
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作者 Shu Li Yi Jing +4 位作者 Xiangyu Zhang Fengran Zhang Qingsong Qi Ningbo Li Le Bai 《River》 2025年第1期106-115,共10页
The Kuye River Basin has experienced a rapid depletion of groundwater due to the increased coal production.In this study,by introducing the empirical equations derived from the three zone theory in the coal mining ind... The Kuye River Basin has experienced a rapid depletion of groundwater due to the increased coal production.In this study,by introducing the empirical equations derived from the three zone theory in the coal mining industry in China as a boundary condition,a calculation model was developed by coupling the soil and water assessment tool and visual modular three-dimensional finite-difference ground-water flow model(SWAT-VISUAL MODFLOW).The model was applied to several coal mines in the basin to quantify the groundwater impact of underground mining.For illustration purposes,two underground water observation stations and one water level station were selected for groundwater change simulation in 2009,producing the results that agreed well with the observed data.We found that groundwater level was closely related to the height of the fractured water-conducting zone caused by underground mining,and a higher height led to a lower groundwater level.This finding was further supported by the calculation that underground mining was responsible for 23.20mm aquifer breakages in 2009.Thus,preventing surface subsidence due to underground mining can help protecting the basin's groundwater. 展开更多
关键词 coupled SWAT-VISUAL MODFLOW GROUNDWATER Kuye River Basin underground mining for coal
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Enhancing the Effectiveness of Overseas Study Programs for University Teachers:Strategies and Influencing Factors
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作者 ZHOU Yuntao 《International Journal of Plant Engineering and Management》 2025年第2期65-79,共15页
Overseas study for university teachers is a crucial path for their professional development and an effective means to enhance the level of education internationalization.However,the effectiveness of these studies is i... Overseas study for university teachers is a crucial path for their professional development and an effective means to enhance the level of education internationalization.However,the effectiveness of these studies is influenced by the various factors,including pre⁃study selection and preparation,management and support in the study period,application and assessment of study outcomes afterward,as well as personal factors such as age,family background,and education experience.This paper aims to explore the impact of these factors on the effectiveness of teachers′international education studies and propose the corresponding improvement suggestions,in order to provide a reference for improving the quality and effectiveness of teachers′studies. 展开更多
关键词 university teachers overseas study and research influencing factors internationalization of education
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The sign of bistable wave speed for a plankton model
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作者 Yuting Wan Jiang Li Hongyong Wang 《International Journal of Biomathematics》 2025年第6期213-226,共14页
The sign of the speed of bistable traveling wave solution is an important focus in the field of population dynamics,since it can be used to predict which species will win the competition and ultimately survive.In this... The sign of the speed of bistable traveling wave solution is an important focus in the field of population dynamics,since it can be used to predict which species will win the competition and ultimately survive.In this paper,the sign of bistable wave speed of a plankton model with cubic nonlinearity is studied.By a delicate analysis,a sufficient condition for bistable wave to be stationary is first obtained.Symmetric and multiplication properties for stationary bistable wave are established.By upper-lower solution method and comparison principle,two sufficient conditions are found so that the bistable wave speed is negative or positive.Moreover,numerical simulations are performed to illustrate our theoretic conclusions. 展开更多
关键词 Propagation direction plankton allelopathy bistable wave.
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Impact of climate changes on Arizona State precipitation patterns using high-resolution climatic gridded datasets
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作者 Hayder H.Kareem Shahla Abdulqader Nassrullah 《Journal of Groundwater Science and Engineering》 2025年第1期34-46,共13页
Climate change significantly affects environment,ecosystems,communities,and economies.These impacts often result in quick and gradual changes in water resources,environmental conditions,and weather patterns.A geograph... Climate change significantly affects environment,ecosystems,communities,and economies.These impacts often result in quick and gradual changes in water resources,environmental conditions,and weather patterns.A geographical study was conducted in Arizona State,USA,to examine monthly precipi-tation concentration rates over time.This analysis used a high-resolution 0.50×0.50 grid for monthly precip-itation data from 1961 to 2022,Provided by the Climatic Research Unit.The study aimed to analyze climatic changes affected the first and last five years of each decade,as well as the entire decade,during the specified period.GIS was used to meet the objectives of this study.Arizona experienced 51–568 mm,67–560 mm,63–622 mm,and 52–590 mm of rainfall in the sixth,seventh,eighth,and ninth decades of the second millennium,respectively.Both the first and second five year periods of each decade showed accept-able rainfall amounts despite fluctuations.However,rainfall decreased in the first and second decades of the third millennium.and in the first two years of the third decade.Rainfall amounts dropped to 42–472 mm,55–469 mm,and 74–498 mm,respectively,indicating a downward trend in precipitation.The central part of the state received the highest rainfall,while the eastern and western regions(spanning north to south)had significantly less.Over the decades of the third millennium,the average annual rainfall every five years was relatively low,showing a declining trend due to severe climate changes,generally ranging between 35 mm and 498 mm.The central regions consistently received more rainfall than the eastern and western outskirts.Arizona is currently experiencing a decrease in rainfall due to climate change,a situation that could deterio-rate further.This highlights the need to optimize the use of existing rainfall and explore alternative water sources. 展开更多
关键词 Spatial Analysis Climate Impact Precipitation Rates CRU Dataset GIS Arizona State USA
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A remote sensing-driven oyster suitability index for marine ranching in the Zhujiang(Pearl)River estuary
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作者 Qilin Chunpi Wenbo He +2 位作者 Zifeng Mo Xinyan Li Jun Zhao 《Acta Oceanologica Sinica》 2025年第8期164-179,共16页
Oyster farming provides substantial ecological and economic benefits but is often constrained by the challenges of selecting suitable sites in dynamic coastal environments.This study presents a tailored oyster suitabi... Oyster farming provides substantial ecological and economic benefits but is often constrained by the challenges of selecting suitable sites in dynamic coastal environments.This study presents a tailored oyster suitability index(OSI)for the Zhujiang(Pearl)River Estuary(PRE),developed using Landsat satellite imagery and in situ observations collected from 2013 to 2023.Key environmental parameters,including sea surface temperature(SST),salinity,turbidity,and chlorophyll-a(Chl-a)concentration,were integrated for OSI retrieval.Optimal algorithms for each parameter were identified through evaluation using field measurements,yielding high accuracy,as evidenced by strong determination coefficients(R^(2))and low root mean square error(RMSE):R^(2)=0.98,RMSE=0.74℃for SST;R^(2)=0.94,RMSE=0.50 for salinity;R^(2)=0.95,RMSE=1.21 mg/m^(3)for Chl-a;R^(2)=0.91,RMSE=1.48 NTU for turbidity.The OSI revealed pronounced seasonal and spatial variability,with the highest suitability observed during winter and the lowest during summer.Validation results demonstrated strong alignment between OSI predictions and existing oyster farming zones.These findings underscore the value of remote sensing for scalable,near-real-time aquaculture site assessments.The OSI framework provides a robust decision-support tool for optimizing oyster cultivation,promoting sustainable aquaculture development in dynamic estuarine systems such as the PRE and beyond. 展开更多
关键词 oyster suitability index remote sensing Landsat 8/9 Zhujiang River estuary marine ranch
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Satellite observations and hydrodynamic simulations of harmful algal blooms in Guangdong coastal waters
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作者 Xiyuan Zeng Jianhang Zhu +12 位作者 Qian Chen Xiaomin Sun Guanxian Huang Shaojie Sun Bin Ai Lin Deng Siyu Chen Yimeng Wang Xi Chen Zihao Chao Xiaochun Shi Chongbin Xu Jun Zhao 《Acta Oceanologica Sinica》 2025年第11期69-89,共21页
Over recent decades,the increasing frequency and intensity of Harmful Algal Blooms(HABs)have resulted in severe environmental impacts worldwide.Understanding the physical drivers of HABs is crucial for understanding t... Over recent decades,the increasing frequency and intensity of Harmful Algal Blooms(HABs)have resulted in severe environmental impacts worldwide.Understanding the physical drivers of HABs is crucial for understanding their dynamics and mitigating their environmental consequences.This study integrates satellite remote sensing and hydrodynamic modeling to investigate two HAB events and their driving mechanisms in Guangdong coastal waters during February and August 2021.An HAB detection method using Sentinel-3 ocean and land color instrument data based on an improved floating algae index algorithm was developed.The spatiotemporal dynamics of physical drivers were analyzed using a submesoscale permitting regional ocean modeling system hydrodynamic simulation.Both HAB detection results and hydrodynamic simulations were validated against in situ buoy measurements.In coastal area of Jiangmen City,local changes of divergence,impacts from the Zhujiang River(Pearl River)fresh water plume were found to be drivers accounted for long-termed variations of chlorophyll and triggers for HABs,while changes in vertical mixing associated with wind speed regulate the short-termed changes.In coastal area of Shantou City,initiations of HABs were mainly driven by wind-induced coastal upwelling.Distribution,aggregation and elongation of HAB patches were modulated by surface fronts and vortices induced by fresh water plume and complex coastlines.These findings underscore the advantages of integrating satellite remote sensing,3D hydrodynamic modeling,and in situ observations for elucidating the complex physical mechanisms governing HAB dynamics in coastal waters. 展开更多
关键词 harmful algal blooms ocean color remote sensing numerical modeling Guangdong coastal waters
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Polyphenol-rich extract from Wisteria floribunda(Willd.)DC.flowers promotes osteoblast differentiation and bone formation by modulating the mTOR pathway
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作者 Jayasingha Arachchige Chathuranga Chanaka Jayasingha Kyoung Tae Lee +4 位作者 Cheng-Yun Jin Yung Hyun Choi Chang Soo Lee Min-Jeong Jung Gi-Young Kim 《Asian Pacific Journal of Tropical Biomedicine》 2025年第8期313-323,共11页
Objective:To investigate the osteogenic effects of polyphenol-rich extracts from Wisteria floribunda(Willd.)DC.(W.floribunda)flowers and elucidate the underlying mechanisms.Methods:Polyphenolic compounds of W.floribun... Objective:To investigate the osteogenic effects of polyphenol-rich extracts from Wisteria floribunda(Willd.)DC.(W.floribunda)flowers and elucidate the underlying mechanisms.Methods:Polyphenolic compounds of W.floribunda extracts were analyzed,including flavonoids and glucoside derivatives.Osteogenic activity was assessed in MC3T3-E1 preosteoblast cells by measurement of alkaline phosphatase(ALP)activity,alizarin red S staining,and the expression of osteogenic markers(RUNX2,SP7,and ALPL).In vivo effects were evaluated in zebrafish larvae by assessing skeletal development and expression of osteogenic genes(runx2a,sp7,and alpl).The role of mammalian target of rapamycin(mTOR)pathway was examined using rapamycin.Results:W.floribunda extracts significantly enhanced ALP activity,bone mineralization,and the expression of RUNX2,SP7,and ALPL in MC3T3-E1 cells.In zebrafish larvae,W.floribunda extracts improved vertebral mineralization and upregulated osteogenic genes.Mechanistically,the plant extract activated the mTOR pathway,and rapamycin treatment attenuated the extracts-induced ALP activity,mineralization,and vertebral formation in zebrafish,confirming mTOR involvement.Conclusions:W.floribunda extracts promote osteoblast differentiation and bone formation via mTOR pathway activation.These findings provide novel insights into the potential of W.floribunda extracts and support its further investigation as a natural therapeutic candidate for bone degenerative disorders such as osteoporosis. 展开更多
关键词 Wisteria floribunda(Willd.)DC. OSTEOGENESIS Bone formation mTOR ZEBRAFISH
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Exploring the dynamics of creative tourism:A tourist-centric perspective to achieve economic sustainable development
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作者 ZOU Fuxia Atefeh AHMADI DEHRASHID +2 位作者 Mehmet AKIF CIFCI Emrah ARSLAN Nina KHALIGHI 《Journal of Mountain Science》 2025年第1期278-295,共18页
Creative tourism is a dynamic and innovative approach to tourism,which points out the importance of people's active participation and their immersion in such experiences.In a vernacular context,it should attract p... Creative tourism is a dynamic and innovative approach to tourism,which points out the importance of people's active participation and their immersion in such experiences.In a vernacular context,it should attract people(local and tourists)attention to accomplish its main goals.Despite its rich cultural and natural assets,Kurdistan province faces several challenges that impact its tourism potential.To achieve that,the study uses quantitative approach to thoroughly analyze and evaluate the components of creative tourism in this province.The research focuses on tourists who visited the province's ten towns during the spring and summer of 2023.Data collection utilized a Likert-scale questionnaire ranging from"very good"to"very poor".The study employed a semistructured questionnaire developed through qualitative interviews alongside a researcher-made questionnaire validated by experts from the University of Kurdistan.The qualitative questionnaire achieved a high-reliability score of 93%using Cronbach's alpha coefficient.In-depth interviews and literary research were conducted to identify creative tourism components and indicators,informing the development of a quantitative questionnaire.Data analysis was performed using SPSS 20 and AMOS software to scrutinize the survey findings,providing insights into enhancing creative tourism strategies in Kurdistan province.The results reveal the varying significance of these dimensions,with the cultural dimension identified as the most crucial(factor loading:0.95),followed by the social(0.92),economic(0.88),and managerial/political dimensions(0.83).The study highlights the importance of cultural planning,community engagement,and infrastructural support in fostering creative tourism.Furthermore,it explores the impact of creative industries,such as music and arts rooted in Kurdish culture,on tourism development.Economic diversification and spatialphysical considerations are critical factors in enhancing Kurdistan's appeal as a creative tourism destination,emphasizing sustainable growth and cultural preservation. 展开更多
关键词 Creative tourism Tourism development Local and regional development Structural equation Iran
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气候变化对中国水资源影响的适应性评估与管理框架 被引量:44
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作者 夏军 Thomas Tanner +6 位作者 任国玉 程晓陶 王金霞 王忠静 严茂超 刘晓洁 Ian Holman 《气候变化研究进展》 CSCD 2008年第4期215-219,共5页
通过论述气候变化对中国水资源影响的适应性评估与管理框架,提出一个气候变化影响决策评估工具,它包括:未来气候变化对中国水资源潜在影响的定性描述分析、半定量与定量分析以及适应性对策评估。由于不同气候区域所面临的水资源问题不同... 通过论述气候变化对中国水资源影响的适应性评估与管理框架,提出一个气候变化影响决策评估工具,它包括:未来气候变化对中国水资源潜在影响的定性描述分析、半定量与定量分析以及适应性对策评估。由于不同气候区域所面临的水资源问题不同,选择中国4个典型案例区域,并确定不同的目标进行气候变化适应性管理综合研究,提出了甄别气候变化影响和适应性管理的新的思路、框架与方法论。该项研究为应对未来气候变化影响的水资源规划与风险管理提供了途径与方法。 展开更多
关键词 气候变化 水资源 适应性管理
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微生物胞外聚合物的研究进展 被引量:9
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作者 皋德祥 邓欢欢 +2 位作者 张明华 葛利云 王红武 《温州医学院学报》 CAS 2012年第3期297-301,共5页
胞外聚合物(extracellular polymeric substance,EPS)是一类有机高分子多聚化合物,相对分子量分布在1×104~3×104之间,它是在特定的生存条件下微生物新陈代谢过程中产生的胞外物质。这类物质可以起到对微生物自身的保护和... 胞外聚合物(extracellular polymeric substance,EPS)是一类有机高分子多聚化合物,相对分子量分布在1×104~3×104之间,它是在特定的生存条件下微生物新陈代谢过程中产生的胞外物质。这类物质可以起到对微生物自身的保护和它们之间相互附着的作用,而且在微生物缺乏营养的条件下可以为其提供营养来源。EPS在微生物群体中广泛存在,EPS有一些独特的性能,使EPS的研究越来越受到人们的重视。 展开更多
关键词 微生物 胞外聚合物 特性 提取方法 组成 综述文献
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淮河流域近500年洪旱事件演变特征分析 被引量:25
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作者 杨传国 陈喜 +4 位作者 张润润 胡琪 余钟波 郝振纯 林朝晖 《水科学进展》 EI CAS CSCD 北大核心 2014年第4期503-510,共8页
为了认识淮河流域过去500年洪旱事件发生规律并鉴别当前的洪旱情势,收集并对比分析了流域实测降雨资料、重建历史雨季降雨资料、历史旱涝等级资料、历史洪旱文献记录和历史调查洪水资料等多源洪旱灾害数据。以重建历史雨季降雨资料和... 为了认识淮河流域过去500年洪旱事件发生规律并鉴别当前的洪旱情势,收集并对比分析了流域实测降雨资料、重建历史雨季降雨资料、历史旱涝等级资料、历史洪旱文献记录和历史调查洪水资料等多源洪旱灾害数据。以重建历史雨季降雨资料和历史旱涝等级资料为主要依据,通过滑动平均、频率计算、小波分析和突变检验等方法,分析流域过去500年洪水干旱时空分布特征和演变规律。结果表明,17世纪淮河流域洪旱灾害最严重,但20世纪极端洪旱事件发生频次最多。淮河流域洪旱事件存在40年左右的稳定长周期,主周期从18世纪的15~20年逐渐减少到19世纪的5年周期,近20年来出现2~3年的主周期,洪旱灾害事件呈增加趋势,流域社会经济发展面临着严峻的洪旱灾害威胁。 展开更多
关键词 洪水 干旱 重建历史降雨 演变特征 淮河流域
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连续纵向水质监测方法在温瑞塘河的应用 被引量:3
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作者 马小雪 李军 +2 位作者 商栩 Randy A Dahlgren 张明华 《中国环境监测》 CAS CSCD 北大核心 2013年第2期131-136,共6页
水质监测结果是水质评价与水污染防治的重要依据。针对常规定点水质监测方法无法完整再现水质指标的时空连续分布特征的问题,将船只搭载的水质实时监测设备与GPS同步形成基于GIS数据支撑的连续纵向水质监测方法。重点对水质监测仪及GPS... 水质监测结果是水质评价与水污染防治的重要依据。针对常规定点水质监测方法无法完整再现水质指标的时空连续分布特征的问题,将船只搭载的水质实时监测设备与GPS同步形成基于GIS数据支撑的连续纵向水质监测方法。重点对水质监测仪及GPS空间数据集成问题进行了分析讨论,并在温瑞塘河流域进行了实验论证。结果表明,连续性纵向水质监测不但能进行连续时空水质监测,还能与GPS、GIS结合进行连续性时空分布特征的分析。 展开更多
关键词 连续性 水质监测 GPS GIS
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2种抗生素对球等鞭金藻的毒理学研究 被引量:8
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作者 皋德祥 宋国梁 +2 位作者 葛利云 邓欢欢 张明华 《浙江农业科学》 2013年第2期179-182,共4页
利用恩诺沙星和盐酸环丙沙星2种抗生素在不同浓度下对球等鞭金藻进行毒理研究。分别对球等鞭金藻的96EC50、叶绿素和过氧化酶活性进行分析。结果表明,2种抗生素对球等鞭金藻的毒理危害等级分别为高毒和中毒。恩诺沙星浓度对叶绿素和过... 利用恩诺沙星和盐酸环丙沙星2种抗生素在不同浓度下对球等鞭金藻进行毒理研究。分别对球等鞭金藻的96EC50、叶绿素和过氧化酶活性进行分析。结果表明,2种抗生素对球等鞭金藻的毒理危害等级分别为高毒和中毒。恩诺沙星浓度对叶绿素和过氧化氢酶活性的抑制影响不大,而盐酸环丙沙星浓度在0~10 mg.L-1范围内对叶绿素和过氧化氢酶活性抑制效果明显,当浓度>10 mg.L-1后抑制效果稳定。 展开更多
关键词 恩诺沙星 盐酸环丙沙星 抗生素 球等鞭金藻 96EC50 过氧化氢酶活性
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雨水生物过滤处理技术在澳大利亚的研究与应用 被引量:4
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作者 张翔凌 Ana Deletic 《武汉理工大学学报》 CAS CSCD 北大核心 2011年第11期116-119,142,共5页
介绍了一种澳大利亚采用的雨水生物过滤处理技术。阐述了FAWB研究人员在系统构型、填料选择、植物选择种植及其净化效果等方面所取得的主要研究成果。针对雨水生物过滤处理技术在悬浮物、重金属离子和营养性污染物去除方面的优势,以及... 介绍了一种澳大利亚采用的雨水生物过滤处理技术。阐述了FAWB研究人员在系统构型、填料选择、植物选择种植及其净化效果等方面所取得的主要研究成果。针对雨水生物过滤处理技术在悬浮物、重金属离子和营养性污染物去除方面的优势,以及在系统构型方面有效储存雨水以回用的特色,提出可对该技术改进为我国的雨水处理系统研究和雨水处理构筑物设计所借鉴的建议。 展开更多
关键词 雨水 生物过滤 污染物去除 回用 填料
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水体中叶绿素a含量短周期预测的研究
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作者 李鹏程 纪晓亮 +1 位作者 梅琨 张明华 《浙江农业科学》 2013年第4期460-463,共4页
通过连续监测数据分别使用线性回归方法和人工神经网络方法建立叶绿素a在短周期内的同步和6步超前预测模型,探讨在短周期内建立叶绿素a含量预测模型的可行性,从而对可能发生的"水华"现象做出前瞻性预测。同时,通过对建立的线... 通过连续监测数据分别使用线性回归方法和人工神经网络方法建立叶绿素a在短周期内的同步和6步超前预测模型,探讨在短周期内建立叶绿素a含量预测模型的可行性,从而对可能发生的"水华"现象做出前瞻性预测。同时,通过对建立的线性回归模型和人工神经网络模型进行比较,发现人工神经网络在预测精度方面较线性模型有一定优势。 展开更多
关键词 逐步线性回归 人工神经网络 叶绿素A
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