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Inheritance and Protection of Native Culture in Campus Landscapes
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作者 郭选昌 高麟腋 《Journal of Landscape Research》 2011年第9期7-10,共4页
Significance and development of native culture was introduced, native culture as an important component of regional characteristics faded out gradually in the "cultural blending" of modern society, but the c... Significance and development of native culture was introduced, native culture as an important component of regional characteristics faded out gradually in the "cultural blending" of modern society, but the construction of socialist cultures with Chinese characteristics must have traditional Chinese cultures as its foundation. Thus, significance of succeeding and protecting native culture was stressed. Functional, cultural and ecological attributes of campus landscapes were analyzed. Campus as a distribution center of knowledge and consciousness guides the development of social consciousness, and also contributes a lot in succeeding and protecting native cultures, so the construction of campus landscapes is of great significance. Landscape design of the new campus of Sichuan Fine Arts Institute was taken for an example to highlight the expression of native "materials", "things" and "conceptions" in campus landscapes, from the perspective of inheritance and protection of native culture, various disciplines such as cultural studies, ecology and psychology were combined to comprehensively analyze application and protection of native culture in campus landscapes, forecast development trend of campus landscapes, so as to guide future development of campus landscapes theoretically and practically. 展开更多
关键词 CAMPUS landscapes native culture INHERITANCE PROTECTION New CAMPUS of SICHUAN Fine ARTS Institute
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Application and Analysis of Native Plant in Landscaping
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作者 龚建勇 史培行 《Journal of Landscape Research》 2010年第3期84-86,91,共4页
With PVESM point of view, this study analyzed comprehensive functions of native plants, which including natural function, visual function, ecological function, social function and spiritual function, the advantages of... With PVESM point of view, this study analyzed comprehensive functions of native plants, which including natural function, visual function, ecological function, social function and spiritual function, the advantages of native plants in landscaping and the effects of it on human living environment were expounded. Based on analyzing the present situations of native plants in landscaping, the relative improvement measures were put forward. 展开更多
关键词 landSCAPING native Plant Ecological system
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Plantations of native shrub species restore soil microbial diversity in the Horqin Sandy Land, northeastern China 被引量:5
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作者 DeMing JIANG ChengYou CAO +2 位作者 Ying ZHANG ZhenBo CUI XiaoShu HAN 《Journal of Arid Land》 SCIE CSCD 2014年第4期445-453,共9页
Caragana microphylla Lam., a leguminous shrub species, plays an important role in revegetation in the degraded ecosystems of the Horqin Sandy Land, Northeastern China. Large areas planted with this shrub have been art... Caragana microphylla Lam., a leguminous shrub species, plays an important role in revegetation in the degraded ecosystems of the Horqin Sandy Land, Northeastern China. Large areas planted with this shrub have been artificially established as sand binders for soil protection, which might change the composition of soil bacterial communities with the development of sand dune stabilization. In this paper, we investigated the diversity and composition of native soil bacterial communities in the C. microphylla plantation for sand fixation using polymerase chain reaction with denaturing gradient gel electrophoresis(PCR-DGGE) to understand the influence of this plantation on sandy soil ecosystem development. We collected soil samples from plantations with an age sequence of 0, 9, 16, and 26 years, as well as from the natural community, to identify the differences among soil bacterial communities. The result showed that bacterial abundance and community composition in the sandy land were affected by the age of the C. microphylla plantation. Moreover, bacterial diversity decreased with increasing plantation age, and the composition of the bacterial community in the 26-year plantation was similar to that in the natural community. Phylogenetic analysis of bands excised from the DGGE gels showed that members of alpha Proteobacterium, gamma Proteobacterium, Gemmatimonadetes and Chloroflexi were dominant in the sandy land. The stabilization of moving sand dune and development of sand-fixed plantation resulted in an increase of soil fertility, which could drive the structural evolvement of soil bacterial community, and it needs over 20 years for the soil bacterial community to form a stable structure, similar to the case for the natural vegetation. 展开更多
关键词 soil bacteria DIVERSITY plantation age denaturing gradient gel electrophoresis Horqin Sandy land
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Geochemistry, mineral paragenesis and geothermal conditions of oreforming fluids from the Ain El Bey Cu–Fe deposit: potential occurrence of native gold and precious metal traces (North African orogenic belt, Northern Tunisia)
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作者 Rania Ben Aissa Wiem Ben Aissa +2 位作者 Said Tlig Lassaad Ben Aissa Abdessalem Ben Haj Amara 《Acta Geochimica》 EI CAS CSCD 2024年第2期366-384,共19页
The Ain El Bey abandoned mine, in North-West Tunisia, fits into the geodynamic context of the European and African plate boundary. Ore deposit corresponds to veins and breccia of multiphase Cu–Fe-rich mineralization ... The Ain El Bey abandoned mine, in North-West Tunisia, fits into the geodynamic context of the European and African plate boundary. Ore deposit corresponds to veins and breccia of multiphase Cu–Fe-rich mineralization related to various hydrothermal fluid circulations. Petromineralogical studies indicate a rich mineral paragenesis with a minimum of seven mineralization phases and, at least, six pyrite generations. As is also the case for galena and native silver, native gold is observed for the first time as inclusion in quartz which opens up, thus, new perspectives for prospecting and evaluating the potential for noble metals associated with the mineralization. Scanning Electron Microscope--Energy Dispersive Spectroscopy and Transmission electron microscopy analyses show, in addition, a large incorporation of trace elements, including Ag and Au, in mineral structures such as fahlores(tetrahedrite-tennantite) and chalcopyrite ones. The mineral/mineral associations, used as geothermometers, gave estimated temperatures for the mineralizing fluids varying from 254 to 330 ℃ for phase Ⅲ, from 254 to 350 ℃ for phase Ⅳ, and from 200 to 300 ℃ for phases Ⅴ and Ⅵ. The seventh and last identified mineralization phase, marked by a deposit of native gold, reflects a drop in the mineralizing fluid’s temperature(< 200 ℃) compatible with boiling conditions. Such results open up perspectives for the development of precious metal research and the revaluation of the Cu–Fe ore deposit at the Ain El Bey abandoned mine, as well as at the surrounding areas fitting in the geodynamic framework of the Africa-Europe plate boundary. 展开更多
关键词 Ore-formingfluids Mineral geochemistry Mineral geothermometers native silver-gold Ain El Bey Ore deposit North Tunisia
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Native and prosthetic septic arthritis in a university hospital in Saudi Arabia:A retrospective study
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作者 Reham Kaki 《World Journal of Orthopedics》 2024年第8期722-733,共12页
BACKGROUND Septic arthritis,whether native or prosthetic,poses a significant challenge in clinical practice due to its potentially devastating consequences.Despite its clinical importance,there remains a dearth of com... BACKGROUND Septic arthritis,whether native or prosthetic,poses a significant challenge in clinical practice due to its potentially devastating consequences.Despite its clinical importance,there remains a dearth of comprehensive studies and standardized diagnostic criteria,particularly in the Kingdom of Saudi Arabia.AIM To investigate the epidemiology,microbiological profiles,and clinical characteristics of native and prosthetic septic joints in the Saudi Arabian population.METHODS Medical records of patients diagnosed with septic arthritis between January 1,2015,and December 31,2022,were retrospectively reviewed.Data regarding patient demographics,clinical presentation,microbiological cultures,treatment modalities,and outcomes were analyzed.RESULTS In a retrospective review of 52 cases of septic arthritis,a balanced gender distribution was observed(1:1 ratio),with the knee being the most commonly affected joint(80.8%).Methicillin-resistant Staphylococcus aureus predominated in native joints(24.2%),while Brucella spp.was more prevalent in prosthetic joints(21.1%).Joint preservation was achieved in most cases(84.6%),with no significant difference in clinical features between native and prosthetic joints.However,certain comorbidities were more common in native joint cases,including renal impairment(P=0.002),hemodialysis(P=0.004),heart disease(P=0.013),and chronic liver disease(P=0.048).At the same time,osteoarthritis was more prevalent in prosthetic joint cases(P=0.013).Vancomycin was the most frequently used antibiotic(26.9%),and most patients received antibiotics before joint aspiration(57.7%).Surgical intervention,predominantly arthrotomy,was required in most cases(32.7%).Notably,a significant association was found between joint type and mortality(odds ratio=0.587,P=0.048),as well as the Charlson comorbidity index and mortality(P=0.001).CONCLUSION This study highlighted distinctive microbiological profiles and etiological factors in septic arthritis cases in the Saudi Arabian population. 展开更多
关键词 Septic arthritis native joint Prosthetic joint EPIDEMIOLOGY Diagnostic criteria Saudi Arabia
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React Native的跨平台移动应用开发实践
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作者 王硕 祁欣颖 《信息与电脑》 2024年第7期119-121,共3页
随着智能手机的普及,移动应用成了连接用户与服务的重要渠道。然而,面对iOS和Android等多个平台,开发者不得不重复开发同一应用以适配不同系统,这不仅消耗了大量的资源,也延长了产品的上市时间。React Native作为一种跨平台移动应用开... 随着智能手机的普及,移动应用成了连接用户与服务的重要渠道。然而,面对iOS和Android等多个平台,开发者不得不重复开发同一应用以适配不同系统,这不仅消耗了大量的资源,也延长了产品的上市时间。React Native作为一种跨平台移动应用开发框架,允许开发者使用Java Script编写应用,一次编码便可在多个平台上运行。本文通过实践案例分析了使用React Native进行跨平台移动应用开发的效率和成本效益,探讨了其在解决平台异质性问题上的有效性,并对比了React Native与其他跨平台框架的优势。结果表明,基于React Native的跨平台开发不仅能够显著提高开发效率,降低开发成本,而且还能提供与原生应用接近的用户体验,为移动应用开发提供了一种高效的解决方案。 展开更多
关键词 React native 跨平台开发 移动应用 开发效率 成本效益
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Coordinative Development Between Land Use Change and Regional Population-Resources-Environment-Development System—A Case Study of Jiangsu Province 被引量:2
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作者 XIAO Sisi HUANG Xianjin PENG Buzhuo 《Chinese Geographical Science》 SCIE CSCD 2007年第4期289-296,共8页
Land use change has significant influence on the operation of the PopulationResources-Environment-De-velopment (PRED) System. Moderate land use is the key factor to ensure the coordinative and sustainable development ... Land use change has significant influence on the operation of the PopulationResources-Environment-De-velopment (PRED) System. Moderate land use is the key factor to ensure the coordinative and sustainable development between land use and PRED system. Based on the internal relationship between land use and PRED system, a PRED evaluation index system and a Press-Status-Response (PSR) model were established in this study. According to the expounding on the mechanism of the PSR model, we investigated the coordinative development between the changes of regional land use and PRED system taking Jiangsu Province as an example. The results showed that the orders of the Synthetic Index of Land Use (SILU) and the Variation of PRED Index (VPI) in Jiangsu are both the southern Jiangsu>the central Jiangsu>the northern Jiangsu. A cubic curve model was used to fit the relationship between the VPI and SILU. The inflection point of VPI was situated in 5.0 of SILU. When SILU was below 5.0, VPI increased with SILU, which will be helpful to the coordinative development between land use and PRED system. Based on those results, it is suggested that the land use degree of the southern Jiangsu, especially that of Nanjing City, should be moderately controlled at present, while land resources of the central Jiangsu and the northern Jiangsu should be further exploited. 展开更多
关键词 land use change Population-Resources-Environment-Development (PRED) system Press-Status-Response (PSR) model coordinative development Jiangsu Province China
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Restoration and Conservation of Deteriorated Arid Land by a Native Thorny Shrub Lycium shawii 被引量:1
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作者 Modi Mohammed Ahmed Ali Mohammed AI-Dousari 《Journal of Agricultural Science and Technology(A)》 2017年第2期100-106,共7页
Land degradation is of great concern in the desert environment of Kuwait, as it has a negative impact on the natural resources. In response to this situation, Kuwait conserves their natural environment by setting asid... Land degradation is of great concern in the desert environment of Kuwait, as it has a negative impact on the natural resources. In response to this situation, Kuwait conserves their natural environment by setting aside areas of significant natural ecosystem, such as wild life center at the Liyah area. The area suffered during the past four decades from severe environmental pressures due to the excessive exploitation of natural resources of sand and gravel as well as overgrazing and military activities. Re-vegetation and restoration programs were applied in the degraded areas in Liyah in December 2003. A large variety of native plants were used for the restoration, however, in this research, only one native perennial drought resistant plant Lycium shawii (Awsaj) was highlighted. Tissue cultured thorny shrub planted at experimental site showed high adaptation on gravel hill side with harsh field condition. Their survival rate was 100% under drip irrigation only 10% was the mortality rate due to improper fixation of irrigation system. The average length of the main stem and the number of branches gradually increased by year from 42 cm with three branches in 2011 to 170 cm with seven branches in 2014. Since Lycium shrubs have the ability to grow in severely degraded areas, with extreme condition of prolonged drought, high temperature and poor nutrient soil as well as their ability to form nabkha, it is considered to be most suitable shrub used for rehabilitation program at Liyah area. 展开更多
关键词 Degraded lands restoration program thomy shrub Lycium shawii.
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Estimating potential harvestable biomass for bioenergy from sustainably managed private native forests in Southeast Queensland, Australia
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作者 michael r.ngugi victor j.neldner +4 位作者 sean ryan tom lewis jiaorong li phillip norman michelle mogilski 《Forest Ecosystems》 SCIE CSCD 2018年第1期62-76,共15页
Background: Australia's energy future is at the crossroads and the role of renewable sources is in focus. Biomass from sustainably managed forests provide a significant opportunity for electricity and heat generatio... Background: Australia's energy future is at the crossroads and the role of renewable sources is in focus. Biomass from sustainably managed forests provide a significant opportunity for electricity and heat generation and production of liquid fuels. Australia has extensive native forests of which a significant proportion are on private land. However, there is limited knowledge on the potential capacity of this resource to contribute to the expansion of a biomass for bioenergy industry. In addition, there are concerns on how to reconcile biomass harvesting with environmental protection. Methods: We used regional ecosystem vegetation mapping for Queensland to stratify harvestable forests within the 1.8 m hectares of private native forests present in the Southeast Queensland bioregion in 2014. We used a dataset of 52,620 individual tree measurements from 541 forest inventory plots collected over the last 10 years. Tree biomass was estimated using current biomass allometric equations for Australia. Biomass potentially available from selective sawlog harvesting and silvicultural treatment across the bioregion was calculated and mapped. Results: Current sawlog harvesting extracts 41.4% of the standing tree biomass and a biomass for bioenergy harvest would retain on average 36% of felled tree biomass on site for the protection of environmental and fauna habitat values. The estimated area extent of harvestable private native forests in the bioregion in 2013 was 888,000 ha and estimated available biomass for bioenergy in living trees was 13.6 million tonnes (t). The spotted gum (Corymbio citriodora subsp, variegata) forests were the most extensive, covering an area of 379,823 ha and with a biomass for bioenergy yield of 14.2 t-ha-1 (with approximately 11.2 t.ha-1 of the biomass harvested from silvicultural thinning and 3 t.ha-1 recovered from sawlog harvest residual). Conclusions: Silvicultural treatment of private native forests in the Southeast Queensland bioregion, has the capacity to supply a large quantity of biomass for bioenergy. The availability of a biomass for bioenergy market, and integration of sawlog harvesting and silvicultural treatment operations, could provide land owners with additional commercial incentive to improve the management of private native forests. This could potentially promote restoration of degraded forests, ecological sustainability and continued provision of wood products. 展开更多
关键词 Renewable energy Forest biomass Woody biomass native forests Silvicultural management Biomassretention Biobased
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Attribution of explanatory factors for change in soil organic carbon density in the native grasslands of Inner Mongolia,China
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作者 JIN Dongyan Phil J MURRAY +5 位作者 XIN Xiaoping QIN Yifei CHEN Baorui QING Gele ZHANG Zhao YAN Ruirui 《Journal of Arid Land》 SCIE CSCD 2018年第3期375-387,共13页
The variation in soil organic carbon density(SOCD) has been widely documented at various spatial and temporal scales. However, an accurate method for examining the attribution of explanatory factors for change in SO... The variation in soil organic carbon density(SOCD) has been widely documented at various spatial and temporal scales. However, an accurate method for examining the attribution of explanatory factors for change in SOCD is still lacking. This study aims to attribute and quantify the key climatic factors, anthropogenic activities, and soil properties associated with SOCD change in the native grasslands of Inner Mongolia, China, by comparing data between the 1960s and the 2010s. In 2007 and 2011, we resampled 142 soil profiles which were originally sampled during 1963–1964 in the native grasslands of Inner Mongolia. SOCD was determined in A horizon(eluvial horizon) of the soil. We selected the explanatory factors based on a random forest method, and explored the relationships between SOCD change and each of the explanatory factors using a linear mixed model. Our results indicated that the change in SOCD varied from the east to the west of Inner Mongolia, and SOCD was 18% lower in the 2010s than in the 1960s. The lower SOCD in the 2010s may primarily be attributed to the increasing in mean annual water surface evaporation, which explained approximately 10% and 50% of the total variation and explainable variation in the change in SOCD, respectively. The sand content of the soil is also a significant explanatory factor for the decrease in SOCD, which explained about 4% and 21% of the total variation and explainable variation in the change in SOCD, respectively. Furthermore, the collection of quantitative information on grazing frequency and duration may also help to improve our understanding of the anthropogenic factors that govern the change in SOCD. 展开更多
关键词 soil organic carbon climate change soil texture mixed linear model effect isolation native grasslands
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Pampa Biome Native Plant Appreciation by the Analysis of <i>Glandularia peruviana</i>(L.) Cuttings Growth
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作者 Luciana Dall’Agnese Cláudia Petry Paloma Alves da Silva Sexto 《American Journal of Plant Sciences》 2015年第3期427-432,共6页
A native plant of Biome Pampa (Southern Brazil), the Glandularia peruviana (L.) Small species has been, until now, little studied as ornamental plant for use as mulch and formation of massifs. Whilst this species didn... A native plant of Biome Pampa (Southern Brazil), the Glandularia peruviana (L.) Small species has been, until now, little studied as ornamental plant for use as mulch and formation of massifs. Whilst this species didn’t suffer any genetic improvement process, it is extremely ornamental by its color and size. In order to promote its comercial propagation and its use to improve the Pampa biodiversity, this study was conducted to know, as a ruderal plant native from South America, how the behavior of the plants was when employed plant propagation and use of artificial auxin on the cuttings. The test consisted of assessing the growth of cuttings treated or not with indol-butyric acid, analyzed at diferent ages, at 21, 24, 27 and 31 days in the University of Passo Fundo, Passo Fundo, Brazil. It was observed that the plant total dry mass values showed no standard of behavior, values for dry matter, whether of leaves, stem, root, shoot and total not responded to treatments and analyzed ages. The same occurred for specific leaf weight, plant height, number of green leaves, number of dead leaves, average leaf length and average number of stems. The lack of significant treatment and age effects may be explained by the plant primitiveness, which is ruderal, so its development has little influenced by the propagation practices. 展开更多
关键词 Glandularia peruviana Indol-Butyric Acid native Plant Age Propagation Ruderal
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Improvement of Native Pasture Productivity through Introduction of Various Types of Palatable Species on Dry Lands in Timor
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作者 Bernadete Barek Koten Redempta Wea +2 位作者 Agustinus Semang Johanis Jermias Victor Lenda 《Journal of Agricultural Science and Technology(A)》 2020年第1期30-33,共4页
This research was aimed to evaluate the productivity of native pasture in Timor Island by introducing various palatable species.The study was carried out on native pasture in Tuatuka,Timor Island for seven months.The ... This research was aimed to evaluate the productivity of native pasture in Timor Island by introducing various palatable species.The study was carried out on native pasture in Tuatuka,Timor Island for seven months.The study was performed by using randomized block design(RBD)with eight treatments(S0:no introduction,S1:Cynodon dactilon,S2:Dicanthium aristatum,S3:C.plectotachyus,S4:Brachiaria decumbens,S5:Desmanthus virgatus,S6:Macroptilium atropurpureum,S7:Clitoria ternatea)with four replications.Procedures on this study include trial plots preparation,tillers preparation for each species,introduction of species in trial plots,maintenance and observation of the productivity.Variables observed were forage production(fresh and dry matter(DM)in ton/ha),nutrient content(%)and stock capacity(animal unit(AU)/ha).Data were analyzed for variance based on RBD and followed by Duncan’s test.Analysis of variance showed that introduction of species had a very significant effect(p<0.01)on all observed variables.The introduction of M.atropurpureum produced the highest fresh forage(2.1 t/ha)and DM production(0.69 t/ha).M.atropurpureum also had the highest DM content(43.61%),nitrogen free extract(52.52%)and stock capacity(1.06 AU/ha).The highest crude protein and crude fiber content were found in D.virgatus(4.31%and 36.62%).The highest extract ether was observed in D.aristatum(1.48%).No introduction had the lowest productivity,but demonstrated the highest ash content.The introduction of palatable species increased the productivity of native pasture in Timor and M.atropupureum was the best introduced species. 展开更多
关键词 Species introduction LEGUME Macroptilium atropurpureum native pasture in Timor forage production GRASS dry land
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基于React Native的用户交互设计
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作者 秦鹏 《电脑编程技巧与维护》 2024年第9期11-13,16,共4页
研究旨在探讨如何在基于React Native的跨平台应用开发中进行有效的人机交互设计。随着移动应用市场的持续扩大,跨平台开发框架(例如,React Native)提供了一种高效的方式来构建应用,但其成功与否往往取决于用户体验的质量。研究重点讨... 研究旨在探讨如何在基于React Native的跨平台应用开发中进行有效的人机交互设计。随着移动应用市场的持续扩大,跨平台开发框架(例如,React Native)提供了一种高效的方式来构建应用,但其成功与否往往取决于用户体验的质量。研究重点讨论了利用React Native的特性和工具来设计具有优秀人机交互的跨平台应用,通过实际案例和技术细节进行了深入探讨。 展开更多
关键词 React native框架 跨平台应用开发 人机交互设计 实践方法
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Heavy Metals in Native Potato and Health Risk Assessment in Highland Andean Zones of Junín, Peru
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作者 Edith Orellana María Carolina Bastos +5 位作者 Walter Cuadrado Rosa Zárate Vicky Sarapura Luz Yallico Fiorella Tabra Diana Bao 《Journal of Environmental Protection》 2020年第11期921-937,共17页
Heavy metals are transferred from the abiotic environment to living organisms, accumulate in food, contaminate the food chain, and are an important route of human exposure involving a potential health risk. In this st... Heavy metals are transferred from the abiotic environment to living organisms, accumulate in food, contaminate the food chain, and are an important route of human exposure involving a potential health risk. In this study, the concentrations of heavy metals (Cd, Fe, Pb, Zn and As) in agricultural soils and tubers of <em>Solanum tuberosum spp. andigena</em> (native potato) were evaluated. Also, an assessment of the health risk associated with the daily intake by the local population was performed in the four districts of the department of Junín, between altitudes of 3800 m to 4200 m. The heavy metals concentrations in soils with native potato cultivation followed the following decreasing order of Fe > Zn > Pb > As > Cd, with values below national standards. The heavy metals content in native potatoes was below the limits recommended by international standards with the exception of Pb. The bioconcentration factor (BCF) for the two native potato varieties in decreasing order was Zn > Cd > Pb > As > Fe, all less than 0.5. The estimated daily intake of metals (EDIM) in adults and children through the consumption of native potatoes was higher for Fe and Zn. The threshold carcinogenic risk values (TCR) for As exceeded the safety limits 1 × 10<sup>-4</sup>. It is concluded that the residents in the four high Andean localities would be exposed to carcinogenic adverse health effects associated with the intake of native potatoes. It is important to monitor the concentration of As and other heavy metals in the Andean soils and crops in order to implement a soil and crop management program to ensure food quality. 展开更多
关键词 Bioconcentration Factor Daily Intake Non-Carcinogenic Risk Carcinogenic Risk native Potato
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The contribution of trace elements from seawater to chimneys:a case study of the native sulfur chimneys in the sea area off Kueishantao,northeast of Taiwan Island
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作者 刘长华 汪小妹 +2 位作者 靳新娣 曾志刚 陈镇东 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2009年第1期162-171,共10页
Hydrothermal fuid containing abundant matter erupts from seafloor, meets ambient cold seawater and forms chimneys. So the main matter origins of chimneys are seawater and matter which are taken by hydrothermal fluid f... Hydrothermal fuid containing abundant matter erupts from seafloor, meets ambient cold seawater and forms chimneys. So the main matter origins of chimneys are seawater and matter which are taken by hydrothermal fluid from deep reservoir. However, because of seawater's little contribution to the forming of chimneys, it is usually covered by the abundant matter which is taken by hydrothermal fluid. Therefore, chimneys formed in ordinary deep elements, cannot be used to study the seawater's seawater hydrothermal activity, containing complex contribution to their formation. While the native sulfur chimneys, formed by hydrothermal activity near the sea area off Kueishantao, are single sulfur composition (over 99%), and within chimneys distinct layers are seen. Different layers were sampled for trace element determination, with Inductively Coupled Plasma Mass Spectrometry (ICP-MS). By analyzing the data, we consider C-layer (secondary inner-layer) as the framework layer of the chimney which formed early (Fig.4), and its trace elements derive from hydrothermal fluid. While the trace elements within A, B, D layers have undergone later alteration. A, B layers are affected by seawater and D layer by hydrothermal fluid. The increase of trace elements of A and B layers was calculated using C layer as background. Based on the known typical volume of chimneys of the near sea area off Kueishantao, we calculated the volume of seawater that contributed trace element to chimneys formation to be about 6.37×10^4 L. This simple quantified estimate may help us better understand the seafloor hydrothermal activity and chimneys. 展开更多
关键词 seafloor hydrothermal activity CHIMNEY native sulfur trace element
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Comparing the climate change mitigation potentials of alternative land uses:Crops for biofuels or biochar vs.natural regrowth
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作者 Anne Cecilie Løvenskiold Xiangping Hu +1 位作者 Wenwu Zhao Francesco Cherubini 《Geography and Sustainability》 2022年第4期347-357,共11页
Using biomass from dedicated crops for energy production and natural vegetation regrowth are key elements in future climate change mitigation scenarios.However,there are still uncertainties about the mitigation potent... Using biomass from dedicated crops for energy production and natural vegetation regrowth are key elements in future climate change mitigation scenarios.However,there are still uncertainties about the mitigation potentials that can be achieved by the different land-based systems and how they perform relative to each other.In this study,we use harmonized future land use datasets to identify global land areas dedicated to second generation bioenergy crop production in 2050 under different climate scenarios.We then assess the global climate change mitigation potentials of using biomass for producing bioethanol with(BECCS)or without carbon capture and storage,biochar,or a synthetic fuel(e-methanol).For the latter,the electricity required to produce hydrogen for e-methanol synthesis is sourced from either wind power or the projected average electricity mix in 2050.Mitigation potential from natural regrowth on the identified land is also quantified.For all the cases,we modelled emissions of greenhouse gases from the life-cycle stages and use parameterized models to estimate local biomass growth rates.The identified land areas range from 1.95 to 13.8 million hectares and can provide from 30 to 178 mega ton(Mt)dry biomass annually from dedicated crops.Climate change mitigation potentials range from 11 to 257 MtCO_(2)-eq.yr^(−1),depending on technological option and land availability.The largest mitigation is delivered by BECCS,but e-methanol can achieve similar findings when hydrogen is sourced from wind power.If hydrogen is produced from grid electricity,e-methanol can result in net positive emissions.E-methanol can also deliver more final energy than bioethanol(4.04 vs.1.27 EJ yr^(−1)).Natural vegetation regrowth can generally achieve higher mitigation than bioethanol,but less than biochar.An optimal combination of BECCS and natural vegetation regrowth can achieve a larger mitigation,up to 281 MtCO_(2)-eq.yr^(−1),indicating that integrated solutions can help to achieve successful land management strategies for climate change mitigation. 展开更多
关键词 Negative emission technologies Natural regrowth land management Bioenergy systems Carbon neutrality
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Implementation Application of Alternative Fuel for Land Transportation Sector in Indonesia Based on Other Countries Experience
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作者 Mirza Mahendra Sutrasno Kartohardjono Yuswan Muharam 《Journal of Energy and Power Engineering》 2013年第3期524-536,共13页
The usage of alternative fuel as a substitute of oil fuel for transportation sector in developed countries has been commonly implemented in order to decrease crude oil consumption, where in a few years back, the crude... The usage of alternative fuel as a substitute of oil fuel for transportation sector in developed countries has been commonly implemented in order to decrease crude oil consumption, where in a few years back, the crude oil price is constantly increasing. In addition, global warming issue becomes one of reasons that motivate many countries to switch for a cleaner energy usage. As a country that has a relatively big reserve of natural gas, its appropriate natural gas could minimize subsidized oil fuel and also financing country's burden if Indonesia is optimizing the usage of energy resources. This paper will discuss about the background of gas fuel usage for road transportation sector in Indonesia, review of alternative fuel usage, the gas fuel usage status in Indonesia and gas usage recommendation for land transportation sector in Indonesia based on other countries experiences. 展开更多
关键词 Alternative fuel cleaner energy gas fuel land transportation.
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syngo NATIVE无对比剂MR血管成像技术 被引量:13
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作者 王超洪 孙志国 +1 位作者 张琼 安靖 《磁共振成像》 CAS 2010年第3期214-217,共4页
syngo NATIVE是西门子磁共振事业部独家推出的无对比剂MR血管成像软件包,经过严格的内部和外部测试,以及全球数十名临床专家的反复应用,获得大量的建议和好评,目前已经成为一种成熟和完善的技术。syngo NATIVE包括两种不同的技术:syngo ... syngo NATIVE是西门子磁共振事业部独家推出的无对比剂MR血管成像软件包,经过严格的内部和外部测试,以及全球数十名临床专家的反复应用,获得大量的建议和好评,目前已经成为一种成熟和完善的技术。syngo NATIVE包括两种不同的技术:syngo NATIVE True FISP和syngo NATIVE SPACE,分别用于腹部动脉(特别是肾动脉)和外周动脉的成像。本文分别对这两种技术的原理以及临床检查的要点进行了介绍。 展开更多
关键词 磁共振成像 血管造影术 syngo native
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Native XML数据库技术综述 被引量:13
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作者 逯鹏 吕良双 高庆一 《计算机科学》 CSCD 北大核心 2004年第4期84-88,共5页
XML成为数据统一描述和表示的标准。如何管理已经出现的大量的XML数据成为重要的问题。NativeXML数据库(NXD)是解决XML数据管理的重要手段。分析和综述了NXD研究现状,以及几个主要研究方向:数据模型、查询语言、存储技术等。分析了NXD... XML成为数据统一描述和表示的标准。如何管理已经出现的大量的XML数据成为重要的问题。NativeXML数据库(NXD)是解决XML数据管理的重要手段。分析和综述了NXD研究现状,以及几个主要研究方向:数据模型、查询语言、存储技术等。分析了NXD的基本特性和具有代表性的NXD系统,最后指出了目前研究存在的不足以及该学科的发展趋势。 展开更多
关键词 native XML 数据库 数据管理 数据模型 数据处理 数据库管理系统
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心脏磁共振成像Native T1 mapping序列对急性心肌炎的诊断价值 被引量:7
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作者 刘钢 范占明 +4 位作者 温兆赢 贺毅 曾牧 赵轶轲 陆东旭 《中国医药》 2016年第5期642-646,共5页
目的 探讨心脏磁共振成像(CMR) Native T1mapping序列对急性心肌炎的诊断价值.方法 选择2014年2月至2015年10月于首都医科大学附属北京安贞医院确诊为急性心肌炎患者25例(急性心肌炎组)和25名健康志愿者(对照组),分别行CMR黑血T2... 目的 探讨心脏磁共振成像(CMR) Native T1mapping序列对急性心肌炎的诊断价值.方法 选择2014年2月至2015年10月于首都医科大学附属北京安贞医院确诊为急性心肌炎患者25例(急性心肌炎组)和25名健康志愿者(对照组),分别行CMR黑血T2、Native T1 mapping及钆对比剂延迟强化(LGE)序列扫描,分析对比左心功能、黑血T2信号强度比、T1弛豫时间、LGE出现部位以及黑血T2、Native T1 mapping、LGE三种序列的诊断效能.结果 急性心肌炎组左心室射血分数、左心室每搏输出量、心排血量明显低于对照组[(55±8)%比(59±7)%、(49±16) ml比(54±12) ml、(3.6±1.0) L/min比(3.9±1.2) L/min],T1弛豫时间、T2信号强度比明显高于对照组[(1 308±56)ms比(1 241 ±20) ms、(1.75±0.23)比(1.57 ±0.14)],差异均有统计学意义(均P<0.05).对照组没有出现LGE,急性心肌炎组47个心肌节段出现LGE,其中位于心外膜下21处(44.7%)和心肌中层22处(46.8%),而侧壁22处(46.8%)和下壁23处(48.9%),25例患者没有出现单独的心内膜下LGE类型.T1mapping序列诊断急性心肌炎的敏感度(91.5%)和准确率(90.4%)要明显高于黑血T2序列(50.3%、64.2%)和LGE序列(73.1%、83.0%),特异度(89.2%)低于LGE序列(96.3%)而高于黑血T2序列(88.5%).结论 CMR T1mapping对于急性心肌炎有很好的诊断价值,其相对于黑血T2和LGE有更高的敏感度和准确率,尤其是对于弥漫性病变及微小的局灶性病变,其量化分析的优势更加明显. 展开更多
关键词 急性心肌炎 磁共振成像 native T1 mapping序列
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