期刊文献+
共找到81篇文章
< 1 2 5 >
每页显示 20 50 100
Comparative Analysis of the Essential Oil of the Underground Organs of Valeriana spp. from Different Countries
1
作者 Ain Raal Valeriia Kokitko +2 位作者 Vira Odyntsova Anne Orav Oleh Koshovyi 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第7期1365-1382,共18页
Valeriana officinalis L.is a plant from the Caprifoliaceae family,which is widely distributed in various parts of the world,especially in Europe and Asia.All species of Valeriana are distinguished by their ability to s... Valeriana officinalis L.is a plant from the Caprifoliaceae family,which is widely distributed in various parts of the world,especially in Europe and Asia.All species of Valeriana are distinguished by their ability to synthesize essen-tial oil,which has a powerful effect on the physiological and mental aspects of the human body.The aim was to study the qualitative and quantitative composition of essential oil from valerian roots,collected in different coun-tries,using the gas chromatography method,and to establish marker compounds for valerian species.13 samples of commercial roots with rhizomes of V.officinalis from nine countries of the world and a sample of Valeriana pratensis and Valeriana stolonifera growing in Ukraine were selected for the study.The essential oil was obtained from dried valerian roots by the distillation method described in the European Pharmacopoeia.To determine the component composition of the essential oils of the selected samples,the methods of gas chromatography with a mass spectrometric detector and capillary gas chromatography were used.The commercial samples of V.offici-nalis from different countries yielded 0.21%–1.03%of essential oil.Only six of 13 samples contained essential oil in an amount that satisfies the requirement of the European Pharmacopoeia standard(not less than 4 mL/kg).150 compounds were identified in the essential oils of 13 samples of V.officinalis essential oils.The range and average content and coefficients of variation of the identified compounds were determined.The principal com-pounds of V.officinalis essential oils were bornyl acetate(1.6%–27.1%),valeranone(0.5%–17.9%),valerenal(0%–14.7%),camphene(0%–14.6%),α-fenchene(0%–10.6%),and valerenic acid(0%–8.5%).The samples of V.pratensis and V.stolonifera yielded rather high levels of essential oil(1.18%and 0.93%,respectively).Three chemotypes of V.officinalis samples were determined-bornyl acetate/valerenal,valeranone,and isovaleric acid.The composition of the three essential oils compared was rather similar.Based on the study results,we propose the following marker compounds for V.officinalis consistently present in all 16 examined samples:bornyl acetate(1.6%–27.1%),limonene(0.2–2.3),and valeranone(0.5%–17.9%).The study of samples from Ukraine indicates the prospects of using these species of the genus Valeriana with the aim of expanding the raw material base and creating potential herbal preparations with a sedative effect,which are extremely necessary for the population of the country in the war and post-war periods. 展开更多
关键词 Valeriana officinalis Valeriana pratensis Valeriana stolonifera volatile compounds TERPENOIDS CHEMOTYPE
下载PDF
Variation in the Composition of the Essential Oil of Commercial Salvia officinalis L.Leaves Samples from Different Countries
2
作者 Ain Raal Anne Orav +4 位作者 Tetiana Ilina Alla Kovalyova Taras Koliadzhyn Yuliia Avidzba Oleh Koshovyi 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第8期2051-2062,共12页
Salvia officinalis L.(Lamiaceae)leaves and its essential oil is used for mouth and throat disorders,skin disorders,minor wounds,and gastrointestinal disorders,and is widely used worldwide.The research aimed to conduct... Salvia officinalis L.(Lamiaceae)leaves and its essential oil is used for mouth and throat disorders,skin disorders,minor wounds,and gastrointestinal disorders,and is widely used worldwide.The research aimed to conduct a comparative study of the composition of S.officinalis essential oils from commercial samples,and their main chemotypes.The volatile constituents from S.officinalis leaves were investigated using gas chromatography(GC).The commercial samples of sage leaves were obtained from retail pharmacies in nine mainly European countries.The yield of essential oil in S.officinalis commercial leaves was between 10.0 and 24.8 mL/kg.The principal components(>5%)among the main identified 25 compounds were 1,8-cineole(8.3%–45.3%),α-thujone(3.0%–34.0%),сamphor(11.3%–29.3%),β-thujone(1.5%–12.9%),viridiflorol(1.1%–10.4%),camphene(2.6%–7.1%),andα-pinene(1.3%–5.8%).In seven(Estonia,England,France,Hungary,Belgium,Ukraine,Georgia)samplesα-thujone dominated.Four samples(Estonia,Georgia,England,Hungary)belong to the most common chemotypeα-thujone>camphor>1,8-cineole.Eight chemotypes of S.officinalis essential oils have been found.Toxic thujones are widespread compounds among them. 展开更多
关键词 SAGE TERPENOIDS CHEMOTYPES thujone TOXICITY
下载PDF
The Thermal Comfort and Hygrothermal Performance of the First Certified Passive House in Estonia
3
作者 Targo Kalamees 《Journal of Civil Engineering and Architecture》 2024年第4期165-174,共10页
This study presents the thermal comfort and hygrothermal performance of building envelope of the first certified passive single-family detached house in Estonia.Temperature and humidity conditions were measured from d... This study presents the thermal comfort and hygrothermal performance of building envelope of the first certified passive single-family detached house in Estonia.Temperature and humidity conditions were measured from different rooms and building envelopes.This article presents analysis of measurement results during the first year after construction.Results showed high room temperature,achieved mainly due to large windows with southern exposure and the small heat loss of the building envelope.High indoor temperature decreased the indoor RH(relative humidity)to quite low levels.Even the RH was low,the moisture excess was high indicating that the design of PH(passive houses)indoor humidity loads cannot be decreased.Humidity in the externally insulated cross-laminated timber panels was observed to be high,caused by drying out of the constructional moisture and the high diffusion resistance of the wood fibre sheathing board.That caused water vapour condensation and risk for mould growth.In conclusion,while planning buildings with high-energy efficiency,more focused attention should be paid to the performance of the building service systems and moisture safety already in the preliminary stages of design. 展开更多
关键词 PH nZEB(nearly zero-energy building) hygrothermal performance moisture safety indoor climate OVERHEATING
下载PDF
Perceptions of Bark Beetle Landscape Disturbance Effects on Natural Resources and Drinking Water: Assessing Communication and Knowledge Exchange in the Rocky Mountain Region, USA
4
作者 Stuart P. Cottrell Katherine Mattor Jana Raadik Cottrell 《Open Journal of Ecology》 2024年第1期77-100,共24页
Widespread changes to forested watersheds affected by the mountain pine beetle (Dendroctonus ponderosae Hopkins) epidemic across western North America raised concerns about the effects of this climate-induced disturba... Widespread changes to forested watersheds affected by the mountain pine beetle (Dendroctonus ponderosae Hopkins) epidemic across western North America raised concerns about the effects of this climate-induced disturbance on drinking water and natural resources. Effective communication and knowledge exchange across scientists and stakeholders (i.e., drinking water managers) is essential for constructively responding to such landscape scale disturbances, providing improved adaptive capacity through knowledge sharing. An assessment of stakeholder knowledge levels, information needs, primary concerns, and suggested communication strategies were conducted via an online elicitation survey and World Science Café workshops. Knowledge levels, assessed via a survey of local water managers and experts, were relatively low with approximately half of the respondents reporting little to no knowledge of the effects of mountain pine beetle on drinking water quality and quantity, thereby indicating limited knowledge exchange between scientists and drinking water stakeholders. Increased accessibility and dissemination of research findings pertinent to the mountain pine beetle epidemic’s effects on drinking water quality and quantity is necessary for natural resource management. Recommendations for improved communication among scientists and drinking water stakeholders in particular and forest health in general include dispersal of non-academic research summaries, information exchange through existing media and community resources, demonstration projects, and information clearinghouses. This information provides a better understanding of the challenges, concerns, and first-hand experience of stakeholders of a landscape disturbance issue to apply this knowledge to enhance land management practice and how researchers on this overall project enhanced science communication efforts. 展开更多
关键词 Adaptive Capacity Climate Change Forested Watersheds Water Quality Water Quantity
下载PDF
The Preliminary Research of Sea Water District Heating and Cooling for Tallinn Coastal Area
5
作者 Allan Hani Teet-Andrus Koiv 《Smart Grid and Renewable Energy》 2012年第3期246-252,共7页
This paper describes possibilities to utilize sea water for district heating and cooling purposes in Tallinn costal area. The sea water temperature profiles and suitability of heating and cooling generation are studie... This paper describes possibilities to utilize sea water for district heating and cooling purposes in Tallinn costal area. The sea water temperature profiles and suitability of heating and cooling generation are studied for continental climatic conditions. The district network study bases on 21 buildings located near to the Gulf of Finland. Industrial reversible heat pump technology is selected to cover heating and cooling loads for the new buildings. Combination of existing district heating and heat pump technology is considered for existing buildings. The results show possibilities, threats and need for further research of the sea water based heat pump district network implementation. 展开更多
关键词 DISTRICT HEATING COOLING SEA Water Heat PUMP RENEWABLE Energy Office Building
下载PDF
Robust Stability Analysis of Smith Predictor Based Interval Fractional-Order Control Systems:A Case Study in Level Control Process
6
作者 Majid Ghorbani Mahsan Tavakoli-Kakhki +1 位作者 Aleksei Tepljakov Eduard Petlenkov 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第3期762-780,共19页
The robust stability study of the classic Smith predictor-based control system for uncertain fractional-order plants with interval time delays and interval coefficients is the emphasis of this work.Interval uncertaint... The robust stability study of the classic Smith predictor-based control system for uncertain fractional-order plants with interval time delays and interval coefficients is the emphasis of this work.Interval uncertainties are a type of parametric uncertainties that cannot be avoided when modeling real-world plants.Also,in the considered Smith predictor control structure it is supposed that the controller is a fractional-order proportional integral derivative(FOPID)controller.To the best of the authors'knowledge,no method has been developed until now to analyze the robust stability of a Smith predictor based fractional-order control system in the presence of the simultaneous uncertainties in gain,time-constants,and time delay.The three primary contributions of this study are as follows:ⅰ)a set of necessary and sufficient conditions is constructed using a graphical method to examine the robust stability of a Smith predictor-based fractionalorder control system—the proposed method explicitly determines whether or not the FOPID controller can robustly stabilize the Smith predictor-based fractional-order control system;ⅱ)an auxiliary function as a robust stability testing function is presented to reduce the computational complexity of the robust stability analysis;andⅲ)two auxiliary functions are proposed to achieve the control requirements on the disturbance rejection and the noise reduction.Finally,four numerical examples and an experimental verification are presented in this study to demonstrate the efficacy and significance of the suggested technique. 展开更多
关键词 Interval uncertainty FOPID controller fractional-order systems robust stability analysis smith predictor
下载PDF
A review of particulate-reinforced aluminum matrix composites fabricated by selective laser melting 被引量:39
7
作者 Pei WANG Jürgen ECKERT +4 位作者 Konda-gokuldoss PRASHANTH Ming-wei WU Ivan KABAN Li-xia XI Sergio SCUDINO 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2020年第8期2001-2034,共34页
Selective laser melting(SLM)is an emerging layer-wise additive manufacturing technique that can generate complex components with high performance.Particulate-reinforced aluminum matrix composites(PAMCs)are important m... Selective laser melting(SLM)is an emerging layer-wise additive manufacturing technique that can generate complex components with high performance.Particulate-reinforced aluminum matrix composites(PAMCs)are important materials for various applications due to the combined properties of Al matrix and reinforcements.Considering the advantages of SLM technology and PAMCs,the novel SLM PAMCs have been developed and researched in recent years.Therefore,the current research progress about the SLM PAMCs is reviewed.Firstly,special attention is paid to the solidification behavior of SLM PAMCs.Secondly,the important issues about the design and fabrication of high-performance SLM PAMCs,including the selection of reinforcement,the influence of parameters on the processing and microstructure,the defect evolution and phase control,are highlighted and discussed comprehensively.Thirdly,the performance and strengthening mechanism of SLM PAMCs are systematically figured out.Finally,future directions are pointed out on the advancement of high-performance SLM PAMCs. 展开更多
关键词 selective laser melting aluminum matrix composites solidification behavior MICROSTRUCTURE PROPERTIES
下载PDF
The Global Stratotype Section and Point (GSSP) for the base of the Katian Stage of the Upper Ordovician Series at Black Knob Ridge, Southeastern Oklahoma, USA 被引量:9
8
作者 Daniel Goldman Stephen A. Leslie +3 位作者 Jaak Nōlvak Seth Young Stig M. Bergstroem Warren D. Huff 《Episodes》 SCIE 2007年第4期258-270,共13页
The Global Boundary Stratotype Section and Point (GSSP) for the Katian Stage of the Upper Ordovician Series is defined as the 4.0 m-level above the base of the Bigfork Chert in the Black Knob Ridge section, southeas... The Global Boundary Stratotype Section and Point (GSSP) for the Katian Stage of the Upper Ordovician Series is defined as the 4.0 m-level above the base of the Bigfork Chert in the Black Knob Ridge section, southeastern Oklahoma. This point in this section is coincident with the first appearance of the graptolite Diplacanthograptus caudatus, which has proved to be a reliable datum for precise worldwide correlation. The FAD ofD. caudatus occurs very near the first occurrences of the graptolites D. lanceolatus, Co.rynoides americanus, Orthograptus pageanus, O. quadrimucronatus, Dicranograptus hians, and Neurograptus margaritatus. This rapid succession of fossil species appearance events provides a secure basis for identification of the base of the Katian Stage of the Upper Ordovician Series and for its global chronostratigraphic correlation. 展开更多
关键词 层形断面 奥陶纪 俄克拉荷马州 美国 地质特点
下载PDF
Management of erectile dysfunction in hypertension:Tips and tricks 被引量:5
9
作者 Margus Viigimaa Charalambos Vlachopoulos +1 位作者 Antonios Lazaridis Michael Doumas 《World Journal of Cardiology》 CAS 2014年第9期908-915,共8页
Arterial hypertension is a major risk factor for cardiovascular disease and affects approximately one third of the adult population worldwide. The vascular origin of erectile dysfunction is now widely accepted in the ... Arterial hypertension is a major risk factor for cardiovascular disease and affects approximately one third of the adult population worldwide. The vascular origin of erectile dysfunction is now widely accepted in the vast majority of cases. Erectile dysfunction is frequently encountered in patients with arterial hypertension and greatly affects their quality of life of hypertensive patients and their sexual partners. Therefore, the management of erectile dysfunction in hypertensive patients is of paramount importance. Unfortunately, erectile dysfunction remains under-reported, under-recognized, and under-treated in hypertensive patients, mainly due to the lack of familiarity with this clinical entity by treating physicians. This review aims to discuss the more frequent problems in the management of hypertensive patients with erectile dysfunction and propose ways to overcome these problems in everyday clinical practice. 展开更多
关键词 Erectile dysfunction HYPERTENSION Antihy-pertensive drugs MANAGEMENT Phosphodiesterase-5 inhibitors Cardiovascular risk
下载PDF
Aberrant glycosylation of the anti-Thomsen-Friedenreich glycotope immunoglobulin G in gastric cancer patients 被引量:3
10
作者 Kristel Kodar Jelena Izotova +3 位作者 Kersti Klaamas Boris Sergeyev Lilian Jrvekülg Oleg Kurtenkov 《World Journal of Gastroenterology》 SCIE CAS 2013年第23期3573-3582,共10页
AIM: To study whether alterations in the glycosylation of immunoglobulin G (IgG) specific to the ThomsenFriedenreich glycotope (TF) have diagnostic and prognostic potential in gastric cancer. METHODS: Serum samples we... AIM: To study whether alterations in the glycosylation of immunoglobulin G (IgG) specific to the ThomsenFriedenreich glycotope (TF) have diagnostic and prognostic potential in gastric cancer. METHODS: Serum samples were obtained from patients with histologically verified gastric carcinoma (n = 89), healthy blood donors (n = 40), and patients with benign stomach diseases (n = 22). The lectin-enzymelinked immunosorbent assay-based glycoprofiling of TF-specific IgG (anti-TF IgG) was performed using synthetic TF-polyacrylamide conjugate as antigen, total IgG purified by affinity chromatography on protein G sepharose, and lectins of various sugar specificities: mannose-specific concanavalin A (ConA), fucose-specificAleuria aurantia lectin (AAL) and sialic acid-specific Sambucus nigra agglutinin (SNA). The sensitivity and specificity of the differences between cancer patients and controls were evaluated by receiver operator characteristic (ROC) curve analysis. Overall survival was analyzed by the Kaplan-Meier method. Time-dependent ROC curve statistics were applied to determine cut-off values for survival analysis. All calculations and comparisons were performed using the GraphPad Prism 5 and SPSS 15.0 software.RESULTS: The level of TF-specific IgG was significantly increased in cancer patients compared with non-cancer controls (P < 0.001). This increase was pronounced mostly in stage 1 of the disease. Cancer patients showed a higher level of ConA binding to antiTF-IgG (P < 0.05) and a very low level of SNA lectin binding (P = 0.0001). No appreciable stage-dependency of the binding of any lectin to anti-TF IgG was found. A strong positive correlation between the binding of AAL and SNA was found in all groups studied (r = 0.71-0.72; P < 0.0001). The changes in ConA reactivity were not related to those of the fucoseor sialic acid-specific lectin. Changes in the SNA binding index and the ConA/SNA binding ratio demonstrated good sensitivity and specificity for stomach cancer: sensitivity 78.79% (95%CI: 61.09-91.02) and 72.73% (95%CI: 57.21-85.04); specificity 79.17 (95%CI: 65.01-89.53) and 88.64% (95%CI: 71.8-96.6), for the SNA binding index and the ConA/SNA binding ratio, respectively. The other combinations of lectins did not improve the accuracy of the assay. The low level of ConA-positive anti-TF IgG was associated with a survival benefit in cancer patients (HR = 1.56; 95%CI: 0.78-3.09; P = 0.19), especially in stages 3-4 of the disease (HR = 2.17; 95%CI: 0.98-4.79; P = 0.048). A significantly better survival rate was found in all cancer patients with a low reactivity of anti-TF IgG to the fucose-specific AAL lectin (HR = 2.39; 95%CI: 1.0-5.7;P = 0.038).CONCLUSION: The changes in the TF-specific IgG glycosylation pattern can be used as a biomarker for stomach cancer detection, and to predict patient survival. 展开更多
关键词 Thomsen-Friedenreich antigen Anticarbohydrate antibodies STOMACH cancer IgG GLYCOSYLATION Survival LECTINS
下载PDF
A Flexible Fin with Bio-Inspired Stiffness Profile and Geometry 被引量:2
11
作者 T. Salumae M. Kruusmaa 《Journal of Bionic Engineering》 SCIE EI CSCD 2011年第4期418-428,共11页
Biological evidence suggests that fish use mostly anterior muscles for steady swimming while the caudal part of the body is passive and, acting as a carrier of energy, transfers the momentum to the surrounding water. ... Biological evidence suggests that fish use mostly anterior muscles for steady swimming while the caudal part of the body is passive and, acting as a carrier of energy, transfers the momentum to the surrounding water. Inspired by those findings we hypothesize that certain swimming patterns can be achieved without copying the distributed actuation mechanism of fish but rather using a single actuator at the anterior part to create the travelling wave. To test the hypothesis a pitching flexible fin made of silicone rubber and silicone foam was designed by copying the stiffness distribution profile and geometry of a rainbow trout. The kinematics of the fin was compared to that of a steadily swimming trout. Fin's propulsive wave length and tail-beat am- plitude were determined while it was actuated by a single servo motor. Results showed that the propulsive wave length and tail-beat amplitude of a steadily swimming 50 cm rainbow trout was achieved with our biomimetic fin while stimulated using certain actuation parameters (frequency 2.31 Hz and amplitude 6.6 degrees). The study concluded that fish-like swimming can be achieved by mimicking the stiffness and geometry of a rainbow trout and disregarding the details of the actuation mechanism. 展开更多
关键词 biomimetics stiffness profile FIN ROBOTICS FISH
下载PDF
Resiliency oriented control of a smart microgrid with photovoltaic modules 被引量:2
12
作者 Sambeet Mishra Kristjan Peterson +3 位作者 Tauno Hilimon Jelena Shuvalova Fushuan Wen Ivo Palu 《Global Energy Interconnection》 EI CAS CSCD 2021年第5期441-452,共12页
The resiliency of a standalone microgrid is of considerable issue because the available regulation measures and capabilities are limited.Given this background,this paper presented a new mathematical model for a detail... The resiliency of a standalone microgrid is of considerable issue because the available regulation measures and capabilities are limited.Given this background,this paper presented a new mathematical model for a detailed photovoltaic(PV)module and the application of new control techniques for efficient energy extraction.The PV module employs a single-stage conversion method to integrate it with the utility grid.For extraction the maximum power from PV and integrate it to power grid,a three-phase voltage source converter is used.For obtaining the maximum power at a particular irradiance a maximum power point tracking(MPPT)scheme is used.The fuzzy logic control and adaptive network-based fuzzy inference system are proposed for direct current(DC)link voltage control.The proposed model and control scheme are validated through a comparison with the standard power-voltage and current-voltage charts for a PV module.Simulation results demonstrate that the system stability can be maintained with the power grid and in the island mode,in contrast with the MPPT. 展开更多
关键词 PV module MPPT Adaptive network-based fuzzy inference system(ANFIS) Converter control Grid integration
下载PDF
Microstructural evolution and mechanical properties of selective laser melted Ti-6Al-4V induced by annealing treatment 被引量:4
13
作者 WANG Pei CHEN Feng-hua +3 位作者 J.ECKERT S.PILZ S.SCUDINO K.G.PRASHANTH 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第4期1068-1077,共10页
Ti-6Al-4V specimens were fabricated by selective laser melting(SLM)to study the effect of thermal treatment on the phase transformation,elemental diffusion,microstructure,and mechanical properties.The results show tha... Ti-6Al-4V specimens were fabricated by selective laser melting(SLM)to study the effect of thermal treatment on the phase transformation,elemental diffusion,microstructure,and mechanical properties.The results show that vanadium enriches around the boundary ofαphases with increasing annealing temperature to 973 K,andα′phases transform intoα+βat 973 K.The typicalα′martensite microstructure transforms to fine-scale equiaxed microstructure at 973 K and the equiaxed microstructure significantly coarsens with increasing annealing temperature to 1273 K.The SLM Ti-6Al-4V alloy annealed at 973 K exhibits a well-balanced combination of strength and ductility((1305±25)MPa and(37±3)%,respectively). 展开更多
关键词 selective laser melting TI-6AL-4V annealing treatment MICROSTRUCTURE mechanical properties
下载PDF
Applicability of Static Supercritical Carbon Dioxide Extraction in Biogeochemical Characterization of Oil Shales 被引量:3
14
作者 Hans Luik Lea Luik +2 位作者 Vilja Palu Galina Sharayeva Andre Gregor 《American Journal of Analytical Chemistry》 2014年第3期173-180,共8页
This study aimed at the assessment of applicability of static supercritical carbon dioxide extraction method (SFE) in biogeochemical characterization of oil shales as an alternative to the standard Soxhlet extration. ... This study aimed at the assessment of applicability of static supercritical carbon dioxide extraction method (SFE) in biogeochemical characterization of oil shales as an alternative to the standard Soxhlet extration. A comparative investigation on yields and compositions of the solvent soluble bitumoids and their constituents extracted from Estonian Kukersite and Dictyonema oil shales by using Soxhlet extraction method (SEM) and static CO2 supercritical fluid extraction in an autoclave at varied subpyrolysis temperatures was carried out. Resulting from TLC- and GC-MS-analyses, aliphatic and aromatic hydrocarbons and neutral oxygen compounds were separated and identified. For the first time, in the composition of the Kukersite bitumoid, homologous series of n-alkanones-3 to n-alkanones-7 were detected. The extracts obtained were similar in both group and individual composition, and geochemical parametres calculated on the basis of aliphatic hydrocarbons including that made static SFE applicable to geochemical investigation of oil shales. 展开更多
关键词 Oil SHALE Bitumoid SUPERCRITICAL EXTRACTION SOXHLET EXTRACTION GEOCHEMICAL Parametres
下载PDF
State of charge and health estimation of batteries for electric vehicles applications:key issues and challenges 被引量:2
15
作者 Samarendra Pratap Singh Praveen Prakash Singh +1 位作者 Sri Niwas Singh Prabhakar Tiwari 《Global Energy Interconnection》 CAS CSCD 2021年第2期145-157,共13页
Using electric vehicles(EVs)for transportation is considered as a necessary component for managing sustainable development and environmental issues.The present concerns regarding the environment,such as rapid fossil f... Using electric vehicles(EVs)for transportation is considered as a necessary component for managing sustainable development and environmental issues.The present concerns regarding the environment,such as rapid fossil fuel depletion,increases in air pollution,accelerating energy demands,global warming,and climate change,have paved the way for the electrification of the transport sector.EVs can address all of the aforementioned issues.Portable power supplies have become the lifeline of the EV world,especially lithium-ion(Li-ion)batteries.Li-ion batteries have attracted considerable attention in the EV industry,owing to their high energy density,power density,lifespan,nominal voltage,and cost.One major issue with such batteries concerns providing a quick and accurate estimation of a battery’s state and health;therefore,accurate determinations of the battery’S performance and health,as well as an accurate prediction of its life,are necessary to ensure reliability and efficiency.This study conducts a review of the technological briefs of EVs and their types,as well as the corresponding battery characteristics.Various aspects of recent research and developments in Li-ion battery prognostics and health monitoring are summarized,along with the techniques,algorithms,and models used for current/voltage estimations,state-of-charge(SoC)estimations,capacity estimations,and remaining-useful-life predictions. 展开更多
关键词 Electric Vehicles State of Charge State of Health Battery Test
下载PDF
The Efficiency Analysis of the Exhaust Air Heat Pump System 被引量:1
16
作者 Alo Mikola Teet-Andrus Koiv 《Engineering(科研)》 2014年第13期1037-1045,共9页
This paper is based on long term parameter measurements of the exhaust air heat pumps (EAHP) system in a new built apartment building. The building was equipped with an exhaust air ventilation system and exhaust air h... This paper is based on long term parameter measurements of the exhaust air heat pumps (EAHP) system in a new built apartment building. The building was equipped with an exhaust air ventilation system and exhaust air heat pump for ventilation heat recover. The results of the measurements show that the COP of the EAHP is mainly related to the temperature graph of the heating system and the supply temperature of domestic hot water (DWH). During the measurement period some other impact factors, such as the quality of maintenance, the nighttime temperature graph of the heating system, the reduction of the exhaust air flows in case of low temperatures, mistakes in designing and low building quality, have also played a role. An analysis of energy consumption shows that in winter conditions the COP is about 3.0 and in the transition period about 3.3. The energy recovery value of the EAHP is 0.5. 展开更多
关键词 Heat Pump Exhaust Air Heat Pump Heat Recovery Heat Requirement COP The Coefficient of Performance
下载PDF
Analysis of Short Sea Shipping-Based Logistics Corridors in the Baltic Sea Region 被引量:1
17
作者 Joachim R. Daduna Kristina Hunke Gunnar Prause 《Journal of Shipping and Ocean Engineering》 2012年第5期304-319,共16页
Despite recent turbulences in global economy, the growth of global trade volumes is expected to continue in the future, leading to increased demands on the performance of logistics networks. The political framework fo... Despite recent turbulences in global economy, the growth of global trade volumes is expected to continue in the future, leading to increased demands on the performance of logistics networks. The political framework for EU (European Union) Transport Policy Development is presented in the EU White Paper on Transport 2011 in order to build a competitive European transport system. One significant aspect is the promotion of multimodal transport in order to decrease terrestrial transport services (road and rail) and to increase services in the maritime transport sector, especially considering the relief of road and railway infrastructure. Looking at the present situation, SSS (Short Sea Shipping) is already used in many different transport fields all around the world. However, there still exists a great potential which currently is not used or not sufficiently exploited for many different reasons. In order to identify the potential use of SSS in multimodal transport, different scenarios in the Baltic Sea Region and the adjoining hinterland have been developed pointing out alternative solutions for routing. These options are analyzed in detail and evaluated from different perspectives (i.e. transport and handling costs, time consumption and transport-related emissions). Afterwards, advantages and disadvantages of each alternative will be examined by taking into account economic and ecological aspects in making decision. 展开更多
关键词 Short sea shipping multimodal transportation transport route optimization.
下载PDF
The Application of the Ground Source and Air-to-Water Heat Pumps in Cold Climate Areas 被引量:3
18
作者 Kaspar Tennokese Teet-Andrus Koiv +1 位作者 Alo Mikola Villu Vares 《Smart Grid and Renewable Energy》 2013年第7期473-481,共9页
This article gives an overview of using the ground source heat pump (GSHP) and air-to-water heat pump (A&WHP) in cold climate areas for heating and for domestic hot water production of buildings. Computer simulati... This article gives an overview of using the ground source heat pump (GSHP) and air-to-water heat pump (A&WHP) in cold climate areas for heating and for domestic hot water production of buildings. Computer simulation and analysis were carried out for a typical detached house, with 200 m2 of living area, the heat demand of 9 kW and the average heat demand for DHW production of 1 kW. In heating period the average Coefficient of Performance (COP) of the A&WHP is considerably lower than COP of the GSHP. 展开更多
关键词 Ground Source Heat Pump Air-Water Heat Pump Heat Requirement COP
下载PDF
Using zircon saturation thermometry of source magma in strongly altered volcanic ashes
19
作者 Tarmo Kiipli 《Acta Geochimica》 EI CAS CSCD 2022年第3期406-418,共13页
The present study deals with the possibilities of applying the zircon saturation thermometry, which is based on the equilibrium between the zircon crystals and the melt, to strongly altered volcanic ashes—bentonites.... The present study deals with the possibilities of applying the zircon saturation thermometry, which is based on the equilibrium between the zircon crystals and the melt, to strongly altered volcanic ashes—bentonites. It proposes an alternative to a widely used method of calculating magma temperature from Zr content and major component composition(Boehnke in Chem Geol351:324–333, 2013), that is not suitable for bentonites, as most of the major components have been largely altered in these rocks. For calculating source magma temperatures in strongly altered volcanic ashes, the exponential function from the Zr(ppm)/Al_(2)O_(3)(%) ratio with compositional corrections from the TiO_(2)/Al_(2)O_(3) ratio was found applicable. The idea to use the ratios of these elements is based on the low mobility of these elements in the earth’s surface conditions. Temperatures of magma, forming in the partial melting process, are assessed from the bulk rock composition. Pre-eruption temperatures were estimated from the composition of fine fractions of bentonites. The accuracy of the new method was established from comparison with the method by Boehnke et al.(Chem Geol 351:324–333,2013). The difference between the two methods was mostly less than ± 30° to ± 50°. The comparison with the magma temperature, estimated from the sanidine composition,revealed 13° lower values on average. Although the proposed method for estimating the source magma temperatures is less precise than the method of accounting for detailed rock compositions, it can be used in strongly altered rocks, where other methods are not usable. The new method still enables differentiation between felsic source magmas originating at low or high temperatures. Early Palaeozoic bentonites in the Baltic Basin can be divided,according to the source magma temperatures, into two types:(1) Low temperature(650–790 ℃), containing potassium-rich sanidine and abundant biotite(S type),(2)high temperature(770–850 ℃) with sodium-rich sanidine and scarce biotite(I type). 展开更多
关键词 ZIRCON Thermometry Volcanic ash Kbentonite Source magma SANIDINE
下载PDF
Emerging Challenges for Numerical Simulations of Quasi-Static Collision Experiments on Laser-Welded Thin-Walled Steel Structures
20
作者 Jani Romanoff &Mihkel Körgesaar Heikki Remes 《Journal of Marine Science and Application》 CSCD 2020年第4期567-583,共17页
This paper re-evaluates recently published quasi-static tests on laser-welded thin-walled steel structures in order to discuss the fundamental challenges in collision simulations based on finite element analysis.Clamp... This paper re-evaluates recently published quasi-static tests on laser-welded thin-walled steel structures in order to discuss the fundamental challenges in collision simulations based on finite element analysis.Clamped square panels were considered,with spherical indenter positioned at the mid-span of the stiffeners and moved along this centerline in order to change the load-carrying mechanism of the panels.Furthermore,the use of panels with single-sided flat bar stiffening and web-core sandwich panels enabled the investigation of the effect of structural topology on structural behavior and strength.The changes in loading position and panel topology resulted in different loading,structural and material gradients.In web-core panels,these three gradients occur at the same locations making the panel global responses sensitive for statistical variations and the failure process time-dependent.In stiffened panel with reduced structural gradient,this sensitivity and time-dependency in failure process is not observed.These observations set challenges to numerical simulations due to spatial and temporal discretization as well as the observed microrotation,which is beyond the currently used assumptions of classical continuum mechanics.Therefore,finally,we discuss the potential of non-classical continuum mechanics as remedy to deal with these phenomena and provide a base for necessary development for future. 展开更多
关键词 Collision and grounding EXPERIMENTS Thin-walled structure Finite element analysis Welding
下载PDF
上一页 1 2 5 下一页 到第
使用帮助 返回顶部