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Modelling of Nature-Based Solutions (NBS) for Urban Water Management—Investment and Outscaling Implications at Basin and Regional Levels 被引量:2
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作者 Berhanu Fanta Alemaw Thebeyame Ron Chaoka Nata Tadesse Tafesse 《Journal of Water Resource and Protection》 2020年第10期853-883,共31页
This manuscript is an attempt to demonstrate effectiveness of nature-based solutions (NBS) and measures to reduce risk of flooding and environmental impact in urban settings. The nature-based solutions (NBS) were asse... This manuscript is an attempt to demonstrate effectiveness of nature-based solutions (NBS) and measures to reduce risk of flooding and environmental impact in urban settings. The nature-based solutions (NBS) were assessed as scenarios from experience of urban storm drainage and sewerage systems based on practices that improve urban water management through modelling using urban stormwater management model (SWMM). The model has been applied in a typical urban environment in the second city in Botswana, the City of Francistown, which has a population of more than one hundred thousand. By considering the 2-yr and 10-year storm events in a calibrated SWMM, NBS scenarios from a mix of low impact and drainage measures were considered. The considered NBS scenarios were used to determine their effectiveness in terms of reducing and controlling peak runoff, flood volumes, infiltration and evapotranspiration in the study area, which are vital in assessing the opportunity and challenge for sustainable management of water resources and associated tradeoff of investments in the urban contexts. The study demonstrates the usefulness of implementing effective measures for achieving NBS in urban context and possibility of outscaling at basin and regional levels. 展开更多
关键词 Modelling of Urban Drainage SWMM Sustainable Urban Water Management nature-based solutions (NBS) Africa
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Kangfuxin solution alleviates esophageal stenosis after endoscopic submucosal dissection:A natural ingredient strategy
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作者 Xin Zhou Dan Ma +7 位作者 Yi-Xiang He Jing Jin Hong-Lian Wang Yun-Feng Wang Fan Yang Jian-Qin Liu Jie Chen Zhi Li 《World Journal of Gastroenterology》 SCIE CAS 2025年第1期110-125,共16页
BACKGROUND Esophageal stricture ranks among the most significant complications following endoscopic submucosal dissection(ESD).Excessive fibrotic repair is a typical pathological feature leading to stenosis after ESD.... BACKGROUND Esophageal stricture ranks among the most significant complications following endoscopic submucosal dissection(ESD).Excessive fibrotic repair is a typical pathological feature leading to stenosis after ESD.AIM To examine the effectiveness and underlying mechanism of Kangfuxin solution(KFX)in mitigating excessive fibrotic repair of the esophagus post-ESD.METHODS Pigs received KFX at 0.74 mL/kg/d for 21 days after esophageal full circumferential ESD.Endoscopic examinations occurred on days 7 and 21 post-ESD.In vitro,recombinant transforming growth factor(TGF)-β1(5 ng/mL)induced a fibrotic microenvironment in primary esophageal fibroblasts(pEsF).After 24 hours of KFX treatment(at 1.5%,1%,and 0.5%),expression ofα-smooth muscle actin-2(ACTA2),fibronectin(FN),and type collagen I was assessed.Profibrotic signaling was analyzed,including TGF-β1,Smad2/3,and phosphor-smad2/3(p-Smad2/3).RESULTS Compared to the Control group,the groups treated with KFX and prednisolone exhibited reduced esophageal stenosis,lower weight loss rates,and improved food tolerance 21 d after ESD.After treatment,Masson staining revealed thinner and less dense collagen fibers in the submucosal layer.Additionally,the expression of fibrotic effector molecules was notably inhibited.Mechanistically,KFX downregulated the transduction levels of fibrotic functional molecules such as TGF-β1,Smad2/3,and p-Smad2/3.In vitro,pEsF exposed to TGF-β1-induced fibrotic microenvironment displayed increased fibrotic activity,which was reversed by KFX treatment,leading to reduced activation of ACTA2,FN,and collagen I.The 1.5%KFX treatment group showed decreased expression of p-Smad 2/3 in TGF-β1-activated pEsF.CONCLUSION KFX showed promise as a therapeutic option for post-full circumferential esophageal ESD strictures,potentially by suppressing fibroblast fibrotic activity through modulation of the TGF-β1/Smads signaling pathway. 展开更多
关键词 Kangfuxin solution natural component Endoscopic submucosal dissection Esophagus stricture Fibrosis
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Urban Planning Based on Nature—A Nature-Based Solution
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作者 Tomislav Đorđević 《Journal of Building Construction and Planning Research》 2023年第1期1-25,共25页
After an international contest announced by the City of Abu Dhabi “Cool Abu Dhabi Challenge”<sup>1</sup> and the article published as a digest of a paper titled A Nature-based Solution [1], the decision ... After an international contest announced by the City of Abu Dhabi “Cool Abu Dhabi Challenge”<sup>1</sup> and the article published as a digest of a paper titled A Nature-based Solution [1], the decision has been made to take part in improving thermal comfort in public spaces by mitigating the impact of the effect of Urban Heat Islands (UHI)<sup>2</sup> in the city of the Belgrade. The basic research aims at achieving the balance between the conflicting impacts when the buildings with their infrastructure and water-green surrounding area are in such correlation that it fulfils acceptable living and heating standards and reduces the use of fossil fuels for cooling the urban areas (buildings). By implementing the remote detection it is possible to analyze and quantify the impact of over-building on the temperature rise in urban areas as well as the disturbance of the heating comfort and the increased demand for additional cooling. Now it is possible to create virtual models that will incorporate this newly-added urban vegetation into urban plans, depending on the evaporation potential that will affect the microclimate of the urban area. Such natural cooling can be measured and adapted and hence aimed at a potential decrease in areas with UHI emissions [2]. Suitable greenery in the summer season can be a useful improvement which concurrently enables and complements several cooling mechanisms—evaporative cooling and evapotranspiration, i.e. natural cooling systems. The remote detection shall establish and map the “healthy” and “unhealthy” greenery zones—that is the vegetation zones with the highest evaporative potential with the “cooling by evaporation” effect and also, by implementing the urban prediction model, it shall propose green infrastructure corridors aimed at a potential decrease in the Urban Heat Island Emission. 展开更多
关键词 nature-base solution (NBS) Urban Heat Islands (UHI) Land Surface Temperature (LST) Land Use and Land Cover (LULC) Normalized Difference Vegetation Index (NDVI)
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Finding Symbolic and All Numerical Solutions for Design Optimization Based on Monotonicity Analysis and Solving Polynomial Systems 被引量:1
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作者 Chen Yong Li Bailin School of Mechanical Engineering , Southwest Jiaotong University, Chengdu 610031, China 《Journal of Modern Transportation》 1996年第1期16-23,共8页
A method for determining symbolic and all numerical solutions in design optimization based on monotonicity analysis and solving polynomial systems is presented in this paper. Groebner Bases of the algebraic system equ... A method for determining symbolic and all numerical solutions in design optimization based on monotonicity analysis and solving polynomial systems is presented in this paper. Groebner Bases of the algebraic system equivalent to the subproblem of the design optimization is taken as the symbolic (analytical) expression of the optimum solution for the symbolic optimization, i.e. the problem with symbolic coefficients. A method based on substituting and eliminating for determining Groebner Bases is also proposed, and method for finding all numerical optimum solutions is discussed. Finally an example is given, demonstrating the strategy and efficiency of the method. 展开更多
关键词 design optimization symbolic optimum solution monotonicity analysis Groebner bases homotopy continuation method
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Variable-Coefficient Mapping Method Based on Elliptical Equation and Exact Solutions to Nonlinear SchrSdinger Equations with Variable Coefficient
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作者 GE Jian-Ya WANG Rui-Min +1 位作者 DAI Chao-Qing ZHANG Jie-Fang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第4X期656-662,共7页
In this paper, by means of the variable-coefficient mapping method based on elliptical equation, we obtain explicit solutions of nonlinear Schrodinger equation with variable-coefficient. These solutions include Jacobi... In this paper, by means of the variable-coefficient mapping method based on elliptical equation, we obtain explicit solutions of nonlinear Schrodinger equation with variable-coefficient. These solutions include Jacobian elliptic function solutions, solitary wave solutions, soliton-like solutions, and trigonometric function solutions, among which some are found for the first time. Six figures are given to illustrate some features of these solutions. The method can be applied to other nonlinear evolution equations in mathematical physics. 展开更多
关键词 variable-coefficient mapping method based on elliptical equation nonlinear Schrodinger equation Jacobian elliptic function solutions solitonic solutions trigonometric function solutions
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An Evaluation Study of a Nature Based Rehabilitation in Sweden for Patients with Exhaustion Disorder
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作者 Gärd Holmqvist Cristina Lundqvist-Persson 《Health》 2021年第9期934-954,共21页
The aim of this study was to evaluate a Nature Based Rehabilitation (NBR) for a group of patients with Exhaustion Disorder (ED) in the southwest Sweden. A multidisciplinary team consisting of an occupational therapist... The aim of this study was to evaluate a Nature Based Rehabilitation (NBR) for a group of patients with Exhaustion Disorder (ED) in the southwest Sweden. A multidisciplinary team consisting of an occupational therapist, a physiotherapist, a medical doctor practising symbolic drama and a nurse with gardening experience provided NBR in an agricultural environment. Patients were offered 14 weeks of rehabilitation in a group of eight persons, three mornings per week. Seventeen patients participated in the study and 15 completed the study. A semi-structured interview was conducted at the beginning of the rehabilitation and at the end and a follow-up interview by telephone was done one year after completion of the rehabilitation. The interviews were recorded and transcribed. Assessment scales used included: Stress and Crisis Inventory (SCI-93), Coping Resources Inventory (CRI) and Visual Analogue Scale (VAS). Weekly notes from the staff members were reviewed and compared with the patient’s own experience. The interviews and the staff notes were analysed with semantic thematic analysis. Result showed that this kind of NBR with a multidisciplinary team promotes improved health and improved quality of life for patients with ED and may thus constitute a good alternative to treatment, provided the ED has not become chronic. 展开更多
关键词 Burn Out Syndrome Exhaustion Disorder Stress Disorder nature based Rehabilitation
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Skin formation in drying a film of soft matter solutions:Application of solute based Lagrangian scheme
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作者 罗凌 孟凡龙 +1 位作者 张俊英 Masao Doi 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第7期356-360,共5页
When a film of soft matter solutions is being dried, a skin layer often forms at its surface, which is a gel-like elastic phase made of concentrated soft matter solutions. We study the dynamics of this process by usin... When a film of soft matter solutions is being dried, a skin layer often forms at its surface, which is a gel-like elastic phase made of concentrated soft matter solutions. We study the dynamics of this process by using the solute based Lagrangian scheme which was proposed by us recently. In this scheme, the process of the gelation(i.e., the change from sol to gel) can be naturally incorporated in the diffusion equation. Effects of the elasticity of the skin phase, the evaporation rate of the solvents, and the initial concentration of the solutions are discussed. Moreover, the condition for the skin formation is provided. 展开更多
关键词 soft matter solution skin formation Onsager principle solute based Lagrangian scheme
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Detection of the Hazards That Threaten Some Coastal Areas, and Ecosystem-Based Solution to Strengthen the Natural Defenses
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作者 Ahmed E. Rakha 《Journal of Geoscience and Environment Protection》 2022年第9期170-184,共15页
The coastal strip of the Nile delta has been vulnerable to environmental hazards. Field surveys, interpretation of Landsat enhanced thematic mapper imageries (ETM), and hydrochemistry analysis of the water samples was... The coastal strip of the Nile delta has been vulnerable to environmental hazards. Field surveys, interpretation of Landsat enhanced thematic mapper imageries (ETM), and hydrochemistry analysis of the water samples was used as methods and materials to detect the hazards associated with climate change which threaten some natural protection coastal areas of the central part of the Nile Delta and assess its magnitude. The invasion of seawaters is the main hazard due to the impacts of global warming phenomena. Elimination of the coastal dunes which act as natural defenses has been accelerating the negative impacts that have been appearing clearly on low-lying lands. Planting that protected areas of the coastal strip are considered the most suitable ecosystem-based and most beneficial solution should be authorized and adopted by the local administration to preserve those areas and adapt to these disasters. 展开更多
关键词 The Ecosystem-based solution Climate Change Sea-Level Rise Coastal Strip natural Protection Nile Delta The Adaption PROTECTION
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Some Potential Solutions to Global Environment Problems & Energy Crisis: Based on Design
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作者 P.M. Wang G. Liu 《Journal of Environmental Science and Engineering》 2010年第6期55-59,共5页
Nowadays human society enters the 21st century, with the rapid economic and technological development, people's material and spiritual requirements has got great satisfaction. However, natural environmental damage br... Nowadays human society enters the 21st century, with the rapid economic and technological development, people's material and spiritual requirements has got great satisfaction. However, natural environmental damage brought by us is also accelerating. Natural disasters happen frequently, including ecological degradation and deterioration, energy resources crisis, greenhouse effect, earthquakes, tsunamis, volcanoes etc. The global crisis has once again waken-up call to mankind. How to properly solve these crises had become a common and urgent responsibility of mankind. This paper will mainly discuss and seek some new potential methods in solving energy crisis and environmental problems from the perspective of automotive and architecture design. As an architect, how to avoid light pollution and reduce heat absorption of roof, increasing heat reflectance of roof are becoming their main and urgent responsibilities. On the other hand, reducing greenhouse effect, researching and developing new low-carbon, low-emission fuel sources are also becoming automotive designers' obligations. Living in harmony with nature & earth is becoming the common human themes of the 21 st century. 展开更多
关键词 Global crisis product architecture design solutions harmony with nature
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Research on Design and Management of Community-Based Ecotourism Model in Aksu-Zhabagly Nature Reserve of Kazakhstan 被引量:1
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作者 Imanaly Akbar Sholpan Abdreyeva +2 位作者 Alexandr Artemyev Markhaba Тumazhanova Gulnar Orynbasarova 《Journal of Geoscience and Environment Protection》 2022年第4期33-48,共16页
This study investigates the community-based ecotourism (CBE) model using a sample of the Aksu-Zhabagly nature reserve (NR). The aim is to propose a suitable CBE model for Aksu-Zhabgly nature-based tourism destinations... This study investigates the community-based ecotourism (CBE) model using a sample of the Aksu-Zhabagly nature reserve (NR). The aim is to propose a suitable CBE model for Aksu-Zhabgly nature-based tourism destinations by employing a combination of field observation, examination, evaluation, and SWOT analysis. The study determines the strategic suggestions for CBE model designing by the results of SWOT analysis. It concludes that convenient transportation and superior location, diversified wild animals and plants, rich in ethnocultural resources, traditional and tranquil life in a typical rural setting, hospitality and positive attitude of locals to tourism and great potential of the region for sustainable development of ecotourism are the strengths. At the same time, the far residential location from the provincial cities, low-quality service, outdated facilities and shortage of skilled employees in tourism management are the main weakness. Another group of constraints to tourism development is lack of tourism marketing and promotion agencies, lack of transparency, poor institution arrangement and corruption, and lack of preferential policies for CBE development. Finally, the paper recommends that economic development, environmental protection, culture and heritage, marketing and image, favorable political environment, and local residents’ empowerment are the main essential to effectively implement the sustainable development of CBE in the Aksu-Zhabagly tourist destination. 展开更多
关键词 MANAGEMENT Community-based Ecotourism MODEL Aksu-Zhabagly nature Reserve Kazakhstan
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THE ANALYTICAL SOLUTIONS BASED ON THE CONCEPT OF FINITE ELEMENT METHODS
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作者 隋允康 郭田福 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1990年第4期321-331,共11页
On the basis of the concept of finite element methods, the rigorous analytical solutions of structural response in terms of the design variables are researched in this paper. The spatial trusses are taken as an exampl... On the basis of the concept of finite element methods, the rigorous analytical solutions of structural response in terms of the design variables are researched in this paper. The spatial trusses are taken as an example for the solution of the analytical expressions of the explicit displacements which are proved mathematically; then some conclusions are reached that are useful to structural sensitivity analysis and optimization. In the third part of the paper, a generalized geometric programming method is sugguested for the optimal model with the explicit displacement. Finally, the analytical solutions of the displacements of three trusses are given as examples. 展开更多
关键词 THE ANALYTICAL solutions based ON THE CONCEPT OF FINITE ELEMENT METHODS
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Market-based solutions:An appropriate approach to resolve environmental problems
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作者 Bei Zhang 《Chinese Journal of Population,Resources and Environment》 2013年第1期87-91,共5页
It was the first time that the Intergovernmental Panel on Climate Change(IPCC),which was founded in 1988,regarded climate change as a significant international political problem(O'Brien and Williams 2007).Over the... It was the first time that the Intergovernmental Panel on Climate Change(IPCC),which was founded in 1988,regarded climate change as a significant international political problem(O'Brien and Williams 2007).Over the next decades,environmentalist and policy makers have been applying many efficient ways to solve various environmental problems and have gained achievements.With the support of successful cases,this paper will focus on the market-based solutions and discuss its advantages compared with the conventional approach. 展开更多
关键词 market-based solutions environmental problems climate change
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Nature-Based Therapy for People Suffering from Post-Concussion Syndrome—A Pilot Study
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作者 Sus Sola Corazon Lisbeth Jul Olsen +1 位作者 Anne-Marie Olsen Ulrik Sidenius 《Health》 2019年第11期1501-1517,共17页
Background: Approximately 10% - 15% of people diagnosed with a concussion develop post-concussion syndrome (PCS), in which mental fatigue is a dominating symptom. PCS has major consequences for the individuals diagnos... Background: Approximately 10% - 15% of people diagnosed with a concussion develop post-concussion syndrome (PCS), in which mental fatigue is a dominating symptom. PCS has major consequences for the individuals diagnosed, and society as a whole. Objective: The objective of the pilot study was to investigate whether a nature-based therapeutic (NBT) intervention would be suitable for ameliorating the symptoms experienced by people with PCS, especially mental fatigue. Method: Eight participants diagnosed with PCS took part in a NBT programme, which consisted of weekly two-hour sessions over the course of eight weeks. The participants’ level of mental fatigue was measured on the Mental Fatigue Scale (MFS) before and after the intervention. An analogue scale inspired by the EuroQol-visual analogue scales (EQ-VAS) was used to measure immediate self-perceived feeling of health/ well-being before and after individual sessions. A semi-structured interview was held with each participant after the intervention. The interviews and logbooks were analysed through content analysis, which entails several steps in a spiral-like process, from reading and re-reading the transcripts to forming units of meaning, which were then grouped into sub-categories and categories for further analysis. Result: The MFS showed a significant decrease in mental fatigue and large effect size. The participants’ self-assessed health/ well-being on the analogue scale showed an increase from the beginning to the end of each session. The analysis of the interviews revealed that the participants experienced the sensory stimuli and exercises in the natural environment as motivating and meaningful, even when they were challenging. Further, they found the psycho-educational aspects transferable to everyday life. Conclusion: The results support that NBT can have potential in the rehabilitation of PCS, by lowering mental fatigue and improving health and well-being. The NBT was further found to be experienced as enjoyable and motivating with good transferability to everyday life. 展开更多
关键词 Mild Traumatic Brain Injury CONCUSSION Mental Fatigue Ecotherapy nature-based Rehabilitation
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Interaction Rule between Rare Earths and LowMelting Point Elements in Fe-,Cu-,AI-,Ni-Base Liquid Solutions 被引量:1
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作者 Du Ting Sun Yunyong +1 位作者 Wu Yeming Wang Longmei 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 1997年第1期15-18,共5页
Interaction rule between representative RE and Sn, Sb, Pb, Cu, S, P low melting point elements respectively in Fe , Cu , Al , Ni base liquid solutions including totally 34 ternary and quarternary systems was inve... Interaction rule between representative RE and Sn, Sb, Pb, Cu, S, P low melting point elements respectively in Fe , Cu , Al , Ni base liquid solutions including totally 34 ternary and quarternary systems was investigated. For each system some thermodynamic properties were obtained, such as the standard free energies of equilibrium reactions, activity interaction coefficients etc .. 展开更多
关键词 rare earth low melting point element FE CU Al and Ni base solution interaction rule
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Natural climate solutions.The way forward 被引量:1
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作者 Caichun Yin Paulo Pereira +1 位作者 Wenwu Zhao Damia Barcelo 《Geography and Sustainability》 CSCD 2023年第2期179-182,共4页
Climate change is a global challenge that threatens global ecological security and sustainable development.Find-ing ways to mitigate their impacts is paramount through engineering carbon storage,low-carbon energy tran... Climate change is a global challenge that threatens global ecological security and sustainable development.Find-ing ways to mitigate their impacts is paramount through engineering carbon storage,low-carbon energy tran-sition,or natural climate solutions(NCS).NCS involve a set of measures(e.g.,afforestation,land restoration,biochar reuse or sustainable land use practices).Implementing NCS increases carbon sequestration and mitigates climate change at the lowest costs and greenest ways.In addition,NCS practices can improve multiple ecosystem services(ES)such as air quality,flood and erosion regulation,pest control,water purification,wild food biomass,recreation or landscape aesthetics.However,unsustainable implementation of NCS,such as over-afforestation of dense mono-forest,can lead to tradeoffs with water supply,wildfire risk,and decreased grasslands and crop-lands.Therefore,to optimise the NCS implementation,reducing the tradeoffs associated and transforming the“expand ecosystem area”to“improve ecosystem management efficiency”is vital.Although NCS can contribute significantly to mitigating climate change,systematic climate actions must be accompanied by a transformation in the global society and investment in new technologies.This will be key to addressing global challenges such as the achievement of Sustainable Development Goals(SDGs),such as SDG 13(Climate Action),SDG 15(Life on Land),SDG 2(Zero Hunger),SDG 3(Good Health and Wellbeing),SDG 6(Clean Water and Sanitation),and SDG 14(Life Bellow Water). 展开更多
关键词 natural climate solutions Climate mitigation Ecosystem services TRADEOFFS Sustainable Development Goals
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Natural Languages Processing for Building Computer- based Learning Tools
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作者 张颖 李娜 《海外英语》 2015年第18期232-234,共3页
This paper outlines a framework to use computer and natural language techniques for various levels of learners to learn foreign languages in Computer-based Learning environment.We propose some ideas for using the comp... This paper outlines a framework to use computer and natural language techniques for various levels of learners to learn foreign languages in Computer-based Learning environment.We propose some ideas for using the computer as a practical tool for learning foreign language where the most of courseware is generated automatically.We then describe how to build Computer-based Learning tools,discuss its effectiveness,and conclude with some possibilities using on-line resources. 展开更多
关键词 naturAL LANGUAGE COMPUTER based learning tools
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Morphological evolution of γ'precipitates in a nickel-based superalloy during various solution treatments 被引量:10
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作者 Zhou, Yu Zhang, Zheng +1 位作者 Zhao, Zihua Zhong, Qunpeng 《Rare Metals》 SCIE EI CAS CSCD 2012年第3期221-226,共6页
The morphological evolution of the γ' phase in nickel-based superalloy жc6y during various solution heat treatments was investigated. The significant changes of the γ' precipitates were observed in the solu... The morphological evolution of the γ' phase in nickel-based superalloy жc6y during various solution heat treatments was investigated. The significant changes of the γ' precipitates were observed in the solution-treated samples. The coarsening and dissolution of γ' phase simulta-neously occurred at intermediate temperatures. In some areas, the primary precipitates became blunt and the adjacent ones were intercon-nected with each other via a diffuse neck, indicating a coarsening process of the primary γ' population. The coarsening was dominated by the precipitate agglomeration mechanism (PAM) rather than by the well-known Ostwald ripening mechanism. In other areas, the partial dissolu-tion of the γ' precipitates began to occur, spreading gradually from dendrite cores to interdendritic regions. In addition, a flower-like γ' struc-ture was developed during the subsolvus solution treatments. The observable long filaments composed of erraticly shaped precipitates were caused by the heterogeneous nucleation of the cooling precipitates during water quenching. 展开更多
关键词 nickel-based superalloy solution heat treatment γ precipitates γ dissolution
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Effect of solid-solution temperature on the microstructure of Fe-Ni based high strength low thermal expansion (HSLTE) alloy 被引量:6
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作者 Yifan Tu Jin Xu +2 位作者 Jianfu Zhang Boping Zhang Dongliang Zhao 《Journal of University of Science and Technology Beijing》 CSCD 2007年第1期46-51,共6页
The influence of solid-solution temperature on the dissolution of carbide precipitates, the average grain size and the microhardness of the austenite matrix in an Fe-Ni based high strength low thermal expansion (HSLT... The influence of solid-solution temperature on the dissolution of carbide precipitates, the average grain size and the microhardness of the austenite matrix in an Fe-Ni based high strength low thermal expansion (HSLTE) alloy was investigated to obtain the proper temperature range of the solid-solution process. The XRD analysis, microstructure observations, and the theoretical calculations showed that the Mo-rich M2C-type precipitates in the Fe-Ni based HSLTE alloy dissolve completely at about 1100℃. The average grain size of the studied alloys increases from 14 to 46 μm in the temperature range of 1050 to 1200℃. The microhardness of the matrix decreases gust for the sake of solid-solution treatment, but then increases later with increasing solution temperature because of the solution strengthening effect. 展开更多
关键词 Fe-Ni based alloy solid-solution temperature MICROSTRUCTURE carbide dissolution
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Thermodynamics and Phase Equilibria for Ce,Y in the Presence of O,S in Ni-base Solutions 被引量:1
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作者 杜挺 王龙妹 +2 位作者 刘爱生 吴夜明 张玉清 《Journal of Rare Earths》 SCIE EI CAS CSCD 1993年第1期25-27,共3页
The deoxidation,desulfuration,deoxysulfuration constants and the standard Gibbs energies(in J mol^(-1))of formation of the following rare earth compounds as the equilibrium phases in Ni-base solutions are given: Ce_2O... The deoxidation,desulfuration,deoxysulfuration constants and the standard Gibbs energies(in J mol^(-1))of formation of the following rare earth compounds as the equilibrium phases in Ni-base solutions are given: Ce_2O_3:lgK=-(6.0729×10~4/T)+16.50 △G^0=-1.162460×10~6+315.84T Ce_2O_2S:lgK=-(5.1450×10~4/T)+12.46 △G^0=-9.84850×10~5+238.50T Ce_2S_3:lgK=-(7.2232×10~4/T)+27.98 △G^0=-1.382600×10~6+535.55T Y_2O_3:lgK=-(4.2572×10~4/T)+7.74 △G^0=-8.14920×10~5+148.16T Y_2O_2S:lgK=-(3.3146×10~4/T)+3.85 △G^0=-6.34460×10~5+73.72T Y_2S_3:lgK=-(1.22487×10~5/T)+55.78 △G^0=-2.344630×10~0+1067.76T Interaction coefficients between Ce.Y and O are also given: e_o^(?)=-(3.33451×10~5/T)+149.7 e_O^(?)=-(1.63437×10~5/T)+71.8 The phase equilibria for Ni-Ce-S-O and Ni-Y-S-O solutions at 1600℃ provide the basis for pre- dicting the sequence and type of Ce and Y equilibrium phases formed in Ni-base solutions.The formulas controlling the morphology of inclusion formed in liquid Ni by Ce or Y addition are also given. 展开更多
关键词 CE Y Ni-base solutions THERMODYNAMICS Phase equilibria
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EXISTENCE OF POSITIVE SOLUTIONS FOR A CLASS OF PARABOLIC EQUATIONS WITH NATURAL GROWTH TERMS AND L^1 DATA
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作者 Kaouther AMMAR Hicham REDWANE 《Acta Mathematica Scientia》 SCIE CSCD 2014年第4期1127-1144,共18页
We study a class of nonlinear parabolic equations of the type:δb(u)/δt-div(a(x,t,u)△u)+y(u)|△u|^2=f,where the right hand side belongs to L^1(Q), b is a strictly increasing C^1-function and -div(a(x... We study a class of nonlinear parabolic equations of the type:δb(u)/δt-div(a(x,t,u)△u)+y(u)|△u|^2=f,where the right hand side belongs to L^1(Q), b is a strictly increasing C^1-function and -div(a(x, t, u)△u) is a Leray-Lions operator. The function g is just assumed to be continuous on R and to satisfy a sign condition. Without any additional growth assumption on u, we prove the existence of a renormalized solution. 展开更多
关键词 renormalized solutions natural growth terms L^1 data
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