期刊文献+
共找到43篇文章
< 1 2 3 >
每页显示 20 50 100
华北地区冬小麦生产潜力数值模拟 被引量:5
1
作者 邬定荣 刘建栋 +2 位作者 刘玲 姜朝阳 于强 《干旱地区农业研究》 CSCD 北大核心 2012年第5期7-14,共8页
利用自然正交分解(EOF)对由机理性作物生长模型模拟的华北地区冬小麦的光温和气候生产潜力结果进行了分析,揭示生产潜力在时空上的分异规律。首先在中国科学院禹城综合试验站进行了冬小麦田间试验,测定了冬小麦生理生态及干物质积累过... 利用自然正交分解(EOF)对由机理性作物生长模型模拟的华北地区冬小麦的光温和气候生产潜力结果进行了分析,揭示生产潜力在时空上的分异规律。首先在中国科学院禹城综合试验站进行了冬小麦田间试验,测定了冬小麦生理生态及干物质积累过程等试验数据。根据试验数据对WOFOST模型进行了改进,获取了相关模型参数并对模型进行了充分验证,验证结果表明模型可以较好地模拟冬小麦生长过程。随后利用验证后的WOFOST模型模拟了华北地区42个站点1961—2006年冬小麦的光温生产潜力和气候生产潜力,并对其进行EOF分析。结果表明华北地区光温生产潜力呈东北高西南低的变化趋势,气候生产潜力大致呈南高北低的趋势,该结果与以往研究结果较为一致。EOF分析则表明,影响光温生产潜力最重要的因子是辐射,其次是温度。影响气候生产潜力最重要的是降水,其次是该区域光温条件的综合效应。 展开更多
关键词 华北地区 冬小麦 光温生产潜力 气候生产潜力 EOF
在线阅读 下载PDF
华北平原夏玉米生产潜力数值模拟及其自然正交分析 被引量:2
2
作者 刘玲 刘建栋 +4 位作者 邬定荣 王治海 邱美娟 姜朝阳 Yu Qiang 《中国农学通报》 CSCD 2013年第33期85-93,共9页
为了明确华北平原夏玉米区域生产潜力的气象要素影响层次,在中国科学院禹城综合试验站进行了夏玉米田间试验,利用Licor-6400便携式光合仪等对夏玉米生长过程进行了较为全面的生理生态参数测定,在此基础上对WOFOST模型进行了相应改进和... 为了明确华北平原夏玉米区域生产潜力的气象要素影响层次,在中国科学院禹城综合试验站进行了夏玉米田间试验,利用Licor-6400便携式光合仪等对夏玉米生长过程进行了较为全面的生理生态参数测定,在此基础上对WOFOST模型进行了相应改进和系统验证,并利用验证后的WOFOST模型对华北平原42个站点1961—2006年夏玉米光温生产潜力和气候生产潜力进行了数值模拟,进行了生产力自然正交分解(EOF)分析。结果表明:模型可以较好地模拟夏玉米生长发育及干物质积累过程。华北平原光温生产潜力变化在7360~11370 kg/hm2之间,平均值为9384 kg/hm2,呈东北高西南低的趋势。光温生产潜力的EOF第一模态方差贡献超过总方差的1/3,前3个模态累计方差贡献达到总方差的62.5%。第一模态在区域上均为正值,具有较好的一致性。气候生产潜力变化在6160~10420 kg/hm2之间,平均值为7906 kg/hm2,与光温生产潜力的区域分布趋势类似,气候生产潜力的EOF前2个模态较为突出,其累计方差贡献可达总方差的1/3。该研究首次将作物数值模拟与EOF方法相结合,进一步揭示了气象要素对夏玉米生产潜力的影响层次关系,可为区域农业布局及决策提供一定的理论支持及实践指导。 展开更多
关键词 华北平原 夏玉米 光温生产潜力 气候生产潜力 EOF
在线阅读 下载PDF
Effect of preparation methods on the performance of CuFe-SSZ-13 catalysts for selective catalytic reduction of NO_x with NH_3 被引量:9
3
作者 Yijiao Wang Lijuan Xie +1 位作者 Fudong Liu Wenquan Ruan 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2019年第7期195-204,共10页
CuFe-SSZ-13 catalyst showed excellent performance in the selective catalytic reduction of NO_x with NH_3(NH_3-SCR) for diesel engine exhaust purification. To investigate the effect of preparation methods on NH_3-SCR p... CuFe-SSZ-13 catalyst showed excellent performance in the selective catalytic reduction of NO_x with NH_3(NH_3-SCR) for diesel engine exhaust purification. To investigate the effect of preparation methods on NH_3-SCR performance, Fe was loaded into one-pot synthesized Cu-SSZ-13 catalysts through solid-state ion-exchange(SSIE), homogeneous deposition precipitation(HDP) and liquid ion-exchange(IE), respectively. Three CuFe-SSZ-13 catalysts showed similar SO_2 resistance, which was better than that of Cu-SSZ-13. The improvement was attributed to the protection of Fe species. Hydrothermal stability of three CuFe-SSZ-13 catalysts was significantly different, which was attributed to the state of active species caused by different preparation methods. Compared with the other two catalysts, more active species existed inside the zeolite pores of CuFe-SSZ-13 SSIE. During hydrothermal aging, the aggregation of these active species in the pores caused the collapse of catalyst structure, ultimately leading to the deactivation of CuFe-SSZ-13 SSIE. In contrast, Fe species was dispersed better on the surface over CuFe-SSZ-13 IE, enhancing the hydrothermal stability of catalysts. Consequently, Fe loading effectively improved the resistance of SO_2 and H_2O over Cu-SSZ-13. For CuFe-SSZ-13, large amounts of active species located inside the zeolite pores are not beneficial for the hydrothermal stability. 展开更多
关键词 NOxremoval CuFe-SSZ-13 PREPARATION methods ACTIVE SPECIES NH3-SCR PERFORMANCE
原文传递
Seasonal and inter-annual variations in carbon fluxes and evapotranspiration over cotton field under drip irrigation with plastic mulch in an arid region of Northwest China 被引量:13
4
作者 Jie BAI Jin WANG +4 位作者 Xi CHEN Ge Ping LUO Hao SHI Long Hui LI Jun Li LI 《Journal of Arid Land》 SCIE CSCD 2015年第2期272-284,共13页
Xinjiang is the largest semi-arid and arid region in China, and drip irrigation under plastic mulch is widely used in this water-limited area. Quantifying carbon and water fluxes as well as investigating their environ... Xinjiang is the largest semi-arid and arid region in China, and drip irrigation under plastic mulch is widely used in this water-limited area. Quantifying carbon and water fluxes as well as investigating their environ- mental drivers over cotton fields is critical for understanding regional carbon and water budgets in Xinjiang, the largest cotton production basin of China. In this study, an eddy covariance (EC) technique was used to measure the carbon and water fluxes of cotton field under drip irrigation with plastic mulch in the growing seasons of 2009, 2010, 2012 and 2013 at Wulanwusu Agrometeorological Experiment Station, a representative oasis cropland in northern Xinjiang. The diurnal patterns of gross primary production (GPP), net ecosystem exchange (NEE) and evapotran-spiration (ET) showed obviously sinusoidal variations from June to September, while the diurnal ecosystem respiration (Res) was stable between daytime and nighttime. The daytime hourly GPP and ET displayed asymptotic rela-tionships with net solar radiation (Rnet), while showed concave patterns with raising vapor pressure deficit (VPD) and air temperature (Ta). The increases in hourly GPP and ET towards the maximum occurred over half ranges of VPD and Ta. The seasonal variations of GPP, NEE and ET were close to the cotton phenology, which almost reached the peak value in July. The cumulative GPP averaged 816.2±55.0 g C/m^2 in the growing season (from April to October), and more than half of GPP was partitioned into NEE (mean value of -478.6±41.4 g C/m^2). The mean seasonal ET was 501.3±13.9 mm, and the mean water use efficiency (WUE) was 1.0+0.1 (mg C/g H2O)/d. The agro-ecosystem behaved as a carbon sink from squaring to harvest period, while it acted as a carbon source before the squaring time as well as after the harvest time. 展开更多
关键词 cotton eddy covariance net ecosystem exchange (NEE) carbon budget water use efficiency (WUE)
在线阅读 下载PDF
Pharmacokinetic evaluation,molecular docking and in vitro biological evaluation of 1,3,4-oxadiazole derivatives as potent antioxidants and STAT3 inhibitors 被引量:2
5
作者 Rashmin khanam Iram I.Hejazi +2 位作者 Syed Shahabuddin Abdul R.Bhat Fareeda Athar 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2019年第2期133-141,共9页
1, 3, 4-Oxadiazole derivatives(4 a–5 f) were previously synthesized to investigate their anticancer properties.However, studies relating to their antioxidant potential and signal transducer and activator of transcrip... 1, 3, 4-Oxadiazole derivatives(4 a–5 f) were previously synthesized to investigate their anticancer properties.However, studies relating to their antioxidant potential and signal transducer and activator of transcription(STAT) inhibition have not been performed. We investigated previously synthesized 1, 3, 4-oxadiazole derivatives(4 a–5 f) for various radical scavenging properties using several in vitro antioxidant assays and also for direct inhibition of STAT3 through molecular docking. The data obtained from various antioxidant assays such as 2, 2,-diphenyl-1-picrylhydrazyl radical(DPPH), nitric oxide, hydrogen peroxide, and superoxide anion radical revealed that among all the derivatives, compound 5 e displayed high antioxidant activities than the standard antioxidant L-ascorbic acid. Additionally, the total reduction assay and antioxidant capacity assay further confirmed the antioxidant potential of compound 5 e. Furthermore, the molecular docking studies performed for all derivatives along with the standard inhibitor STX-0119 showed that binding energy released in direct binding with the SH2 domain of STAT3 was the highest for compound 5 e(-9.91 kcal/mol).Through virtual screening, compound 5 e was found to exhibit optimum competency in inhibiting STAT3 activity. Compound 5 e decreased the activation of STAT3 as observed with Western blot. In brief, compound5 e was identified as a potent antioxidant agent and STAT3 inhibitor and effective agent for cancer treatment. 展开更多
关键词 1 3 4-oxadiazoles STRUCTURE-ACTIVITY relationship (SAR) Antioxidant activities STAT3 INHIBITORS Molecular DOCKING
暂未订购
Incorporation of a nanotechnology-based additive in cementitious products for clay stabilisation 被引量:3
6
作者 E.U.Eyo S.Ng’ambi S.J.Abbey 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2020年第5期1056-1069,共14页
The mechanical performances and water retention characteristics of clays,stabilised by partial substitution of cement with by-products and inclusion of a nanotechnology-based additive called RoadCem(RC),are studied in... The mechanical performances and water retention characteristics of clays,stabilised by partial substitution of cement with by-products and inclusion of a nanotechnology-based additive called RoadCem(RC),are studied in this research.The unconfined compression tests and one-dimensional oedometer swelling were performed after 7 d of curing to understand the influence of addition of 1%of RC material in the stabilised soils with the cement partially replaced by 49%,59%and 69%of ground granulated blast furnace slag(GBBS)or pulverised fuel ash(PFA).The moisture retention capacity of the stabilised clays was also explored using the soil-water retention curve(SWRC)from the measured suctions.Results confirmed an obvious effect of the use of RC with the obtained strength and swell properties of the stabilised clays suitable for road application at 50%replacement of cement.This outcome is associated with the in-depth and penetrating hydration of the cementitious materials by the RC and water which results in the production of needle-like matrix with interlocking filaments e a phenomenon referred to as the‘wrapping’effect.On the other hand,the SWRC used to describe the water holding capacity and corresponding swell mechanism of clays stabilised by a proportion of RC showed a satisfactory response.The moisture retention of the RC-modified clays was initially higher but reduced subsequently as the saturation level increased with decreasing suction.This phenomenon confirmed that clays stabilised by including the RC are water-proof in nature,thus ensuring reduced porosity and suction even at reduced water content.Overall,the stabilised clays with the combination of cement,GGBS and RC showed a better performance compared to those with the PFA included. 展开更多
关键词 CEMENT Ground granulated blast furnace slag(GBBS) Fly ash RoadCem(RC) SWELL Stabilisation Unconfined compressive strength Soil-water retention curve(SWRC)
在线阅读 下载PDF
Structural & Magnetic Characterizations of NiLiZn Nanoferrites Synthesized by Co-precipitation Method 被引量:1
7
作者 D.N. Rohadiana Z.A.Z. Jamal +2 位作者 S.B. Jamaludin M.F. Bari J. Adnan 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2011年第11期991-995,共5页
Synthesis of Ni0.sLixZn(0.5-x)Fe204 nanoparticles with x=0, 0.1, 0.2, 0.3, 0.4 and 0.5 were realized via coprecipitation method. X-ray diffraction (XRD) and vibrating sample magnetometer (VSM) measurements were ... Synthesis of Ni0.sLixZn(0.5-x)Fe204 nanoparticles with x=0, 0.1, 0.2, 0.3, 0.4 and 0.5 were realized via coprecipitation method. X-ray diffraction (XRD) and vibrating sample magnetometer (VSM) measurements were performed on the samples to determine the characteristics of the crystal structures and the magnetic properties of the samples, respectively. The spinel phase structures of the samples were confirmed by XRD analysis. Patterns of decreased lattice parameter and increased crystallite size values were observed by increasing the Li concentration at longer synthesis reaction periods. Similarly, for the magnetic properties, both the saturation magnetization (Ms) and coercivity (Hc) were found to vary with increasing patterns at higher Li doping levels and longer synthesis reaction periods. The results and mechanisms concerned were discussed. 展开更多
关键词 Lithium nickel zinc ferrite CO-PRECIPITATION Crystal structure Magnetic properties
原文传递
Multiclass stand-alone and ensemble machine learning algorithms utilised to classify soils based on their physico-chemical characteristics 被引量:2
8
作者 Eyo Eyo Samuel Abbey 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2022年第2期603-615,共13页
This study has provided an approach to classify soil using machine learning.Multiclass elements of stand-alone machine learning algorithms(i.e.logistic regression(LR)and artificial neural network(ANN)),decision tree e... This study has provided an approach to classify soil using machine learning.Multiclass elements of stand-alone machine learning algorithms(i.e.logistic regression(LR)and artificial neural network(ANN)),decision tree ensembles(i.e.decision forest(DF)and decision jungle(DJ)),and meta-ensemble models(i.e.stacking ensemble(SE)and voting ensemble(VE))were used to classify soils based on their intrinsic physico-chemical properties.Also,the multiclass prediction was carried out across multiple cross-validation(CV)methods,i.e.train validation split(TVS),k-fold cross-validation(KFCV),and Monte Carlo cross-validation(MCCV).Results indicated that the soils’clay fraction(CF)had the most influence on the multiclass prediction of natural soils’plasticity while specific surface and carbonate content(CC)possessed the least within the nature of the dataset used in this study.Stand-alone machine learning models(LR and ANN)produced relatively less accurate predictive performance(accuracy of 0.45,average precision of 0.5,and average recall of 0.44)compared to tree-based models(accuracy of 0.68,average precision of 0.71,and recall rate of 0.68),while the meta-ensembles(SE and VE)outperformed(accuracy of 0.75,average precision of 0.74,and average recall rate of 0.72)all the models utilised for multiclass classification.Sensitivity analysis of the meta-ensembles proved their capacities to discriminate between soil classes across the methods of CV considered.Machine learning training and validation using MCCV and KFCV methods enabled better prediction while also ensuring that the dataset was not overfitted by the machine learning models.Further confirmation of this phenomenon was depicted by the continuous rise of the cumulative lift curve(LC)of the best performing models when using the MCCV technique.Overall,this study demonstrated that soil’s physico-chemical properties do have a direct influence on plastic behaviour and,therefore,can be relied upon to classify soils. 展开更多
关键词 Soil classification Physico-chemistry Soil plasticity Machine learning Logistic regression(LR) Machine learning ensembles Artificial neural network(ANN)
在线阅读 下载PDF
Sustained neuronal viability by paracrine factors: new opportunities for endothelial progenitor cell secretome 被引量:1
9
作者 Stefano Di Santo Hans Rudolf Widmer 《Neural Regeneration Research》 SCIE CAS CSCD 2021年第7期1429-1430,共2页
Despite the big progresses in the field of regenerative medicine, the loss of neurons remains essentially an unresolved challenge.Among the different approaches under investigation, there are great expectations on ste... Despite the big progresses in the field of regenerative medicine, the loss of neurons remains essentially an unresolved challenge.Among the different approaches under investigation, there are great expectations on stem and progenitor cells-based strategies. 展开更多
关键词 PROGENITOR strategies. SPITE
暂未订购
The Youth Fitness International Test(YFIT)battery for monitoring and surveillance among children and adolescents:A modified Delphi consensus project with 169 experts from 50 countries and territories
10
作者 Francisco B.Ortega Kai Zhang +23 位作者 Cristina Cadenas-Sanchez Mark S.Tremblay Gregor Jurak Grant R,Tomkinson Jonatan R.Ruiz Katja Keller Christine Delisle Nystrom Jennifer MSacheck Russell Pate Kathryn LWeston Tetsuhiro Kidokoro Eric TPoon Lucy-Joy M.Wachira Ronald Ssenyonga Thayse Natacha Q.F.Gomes Carlos Cristi-Montero Brooklyn J.Fraser Claudia Niessner Vincent O.Onywera Yang Liu Li-Lin Liang Stephanie A.Prince Justin J.Lang the Delphi Fitness Expert Group 《Journal of Sport and Health Science》 2025年第4期48-63,共16页
Background:Physicalfitness in childhood and adolescence is associated with a variety of health outcomes and is a powerful marker of current and future health.However,inconsistencies in tests and protocols limit interna... Background:Physicalfitness in childhood and adolescence is associated with a variety of health outcomes and is a powerful marker of current and future health.However,inconsistencies in tests and protocols limit international monitoring and surveillance.The objective of the study was to seek international consensus on a proposed,evidence-informed,Youth Fitness International Test(YFIT)battery and protocols for health monitoring and surveillance in children and adolescents aged 618 years.Methods:We conducted an international modified Delphi study to evaluate the level of agreement with a proposed,evidence-based,YFIT of core health-relatedfitness tests and protocols to be used worldwide in 6-to 18-year-olds.This proposal was based on previous European and North American projects that systematically reviewed the existing evidence to identify the most valid,reliable,health-related,safe,and feasiblefitness tests to be used in children and adolescents aged 618 years.We designed a single-panel modified Delphi study and invited 216 experts from all around the world to answer this Delphi survey,of whom one-third are from low-to-middle income countries and one-third are women.Four experts were involved in the piloting of the survey and did not participate in the main Delphi study to avoid bias.We pre-defined an agreement of 80%among the expert participants to achieve consensus.Results:We obtained a high response rate(78%)with a total of 169fitness experts from 50 countries and territories,including 63 women and 61 experts from low-or middle-income countries/territories.Consensus(>85%agreement)was achieved for all proposed tests and protocols,supporting the YFIT battery,which includes weight and height(to compute body mass index as a proxy of body size/composition),the 20-m shuttle run(cardiorespiratoryfitness),handgrip strength,and standing long jump(muscularfitness).Conclusion:This study contributes to standardizingfitness tests and protocols used for research,monitoring,and surveillance across the world,which will allow for future data pooling and the development of international and regional sex-and age-specific reference values,health-related cut-points,and a global picture offitness among children and adolescents. 展开更多
关键词 FITNESS Experts DELPHI Protocols Youth Fitness International Test
在线阅读 下载PDF
Atomically dispersed catalysts for small molecule electrooxidation in direct liquid fuel cells 被引量:2
11
作者 Jinfa Chang Guanzhi Wang +1 位作者 Wei Zhang Yang Yang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第5期439-453,共15页
Direct liquid fuel cells(DLFCs) have received increasing attention because of their high energy densities,instant recharging abilities, simple cell structure, and facile storage and transport. The main challenge for t... Direct liquid fuel cells(DLFCs) have received increasing attention because of their high energy densities,instant recharging abilities, simple cell structure, and facile storage and transport. The main challenge for the commercialization of DLFCs is the high loading requirement of platinum group metals(PGMs) as catalysts. Atomically dispersed catalysts(ADCs) have been brought into recent focus for DLFCs due to their well-defined active sites, high selectivity, maximal atom-utilization, and anti-poisoning property. In this review, we summarized the structure–property relationship for unveiling the underlying mechanisms of ADCs for DLFCs. More specifically, different types of fuels used in DLFCs such as methanol, formic acid,and ethanol were discussed. At last, we highlighted current challenges, research directions, and future outlooks towards the practical application of DLFCs. 展开更多
关键词 Atomic dispersion ELECTROCATALYST Small molecule electrooxidation Direct liquid fuel cells
在线阅读 下载PDF
A comparison of lower limb stiffness and mechanical muscle function in ACL-reconstructed,elite,and adolescent alpine ski racers/ski cross athletes 被引量:2
12
作者 Matthew J.Jordan Per Aagaard Walter Herzog 《Journal of Sport and Health Science》 SCIE 2018年第4期416-424,共9页
Purpose: The aim of this study was to compare mechanical muscle function in the eccentric/concentric phases of vertical bilateral jumping in anterior cruciate ligament-reconstructed (ACLR), elite (ELITE), and ado... Purpose: The aim of this study was to compare mechanical muscle function in the eccentric/concentric phases of vertical bilateral jumping in anterior cruciate ligament-reconstructed (ACLR), elite (ELITE), and adolescent (ADOL) alpine ski racers and ski cross athletes. Methods: Alpine ski racers/ski crossers (ACLR: n = 12, age = 26.7 ± 3.8 years; ELITE: n = 12, age = 23.9 ± 3.0 years; ADOL: n = 12, age = 17.8 ± 0.7 years; females: n = 6 per group, males: n = 6 per group) performed 5 maximal countermovement jumps (CMJs) and 5 squat jumps. The ground reaction forces for each limb were analyzed using dual force plate recording to obtain body center of mass (BCM) velocity, displacement, and power. The eccentric deceleration (ECC) and concentric phases were determined from BCM velocity. CMJ net concentric and ECC impulses were calculated (body mass normalized) along with the peak and mean BCM power and maximal vertical jump height. CMJ lower limb stiffness (LLS) was determined by the slope of the ground reaction forces vs. the BCM displacement curve over the ECC phase. Concentric and ECC asymmetry indices were calculated for each leg, and the left vs. right LLS was compared. Outcome measures (reported as mean ± SD) calculated as a 5-jump mean were normalized to body mass and compared using an analysis of variance. Results: No between-group differences were found for peak and mean power or jump heights. There were no group differences for LLS or net concentric phase impulse, but the net ECC impulse was lower in the ADOL group compared with ELITE skiers (ADOL: 1.33 ± 0.32 Ns/kg; ELITE: 1.59 ± 0.16 Ns/kg; p 〈 0.05). Although no group differences were found for ECC asymmetry indices, a group × limb interaction was found for LLS (p 〈 0.01), which was systematically higher in the right vs. the left limb of ADOL skiers (right: 54.1 ± 17.9 N/m/kg; left: 48.7 ± 15.7 N/m/kg;p 〈 0.01). Conclusion: ADOL skiers demonstrated decreased ECC impulse and systematic right limb dominance in LLS compared with ACLR and ELITE skiers. The implication of these findings for injury and performance are unknown, but further investigation into these potential relationships is warranted.2018 Published by Elsevier B.V. on behalf of Shanghai University of Sport. This is an open access article under the CC BY-NC-ND license. (http://creativecommons.org/licenses/by-nc-nd/4.0/). 展开更多
关键词 Between-limb asymmetry Injury prevention Knee injuries Muscle power Vertical jump
在线阅读 下载PDF
Taxonomic and metabolic shifts in the Coorong bacterial metagenome driven by salinity and external inputs 被引量:1
13
作者 Kelly NEWTON Thomas C.JEFFRIES +3 位作者 Renee J.SMITH Justin R.SEYMOUR Laurent SEURONT James G.MITCHELL 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2018年第6期2033-2049,共17页
The Coorong estuary lies at the terminus of Australia's largest river system, the Murray-Darling; both are strongly influenced by human activities; including farming and extensive flow modification. Metagenomic ap... The Coorong estuary lies at the terminus of Australia's largest river system, the Murray-Darling; both are strongly influenced by human activities; including farming and extensive flow modification. Metagenomic approaches were used to determine the planktonic bacterial community composition and potential metabolic function at two extremes in the Coorong, the river mouth which exhibits marine-like salinity, and the hypersaline upper-reaches of the estuary. Significant shifts in taxa and metabolic function were seen between the two sites. The river mouth exhibited an increase in abundance of R hodobacteriaceae and Alteromonadaceae; families readily able to adapt to change in nutrient conditions; and the potentially pathogenic families B rucellaceae, Enterobacteriaceae and Vibrionaceae. Metabolisms over-represented include motility and chemotaxis, RNA metabolism and membrane transport, all of which are involved in actively searching for and obtaining nutrients. Also over-represented were metabolisms involved in population succession and stress response. An over-representation of taxa and metabolisms indicative of environmental change is reflective of anthropogenically af fected riverine input. In the hypersaline upper reaches of the estuary, the halophilic family Ectothiorhodospiraceae was over-represented, as were the families Flavobacteriaceae, Cytophagaceae and Nocardioidaceae, members of which are able to survive over a wide salinity range. Metabolisms over-represented here were reflective of increased bacterial growth, characteristic of hypersaline environments, and included DNA metabolism, nucleotide and nucleoside synthesis and cell cycle. Coorong metagenomes clustered taxonomically and metabolically with other planktonic metagenomes, but remained an outlier of this group with only 71% and 84% similarity, respectively. This indicates that the Coorong exhibits a unique planktonic bacterial community that is influenced by riverine input at the river mouth and salinity in the upper-reaches. 展开更多
关键词 HYPERSALINE ESTUARY bacteria taxonomy metabolic potential
在线阅读 下载PDF
Excellent photoluminescence and electrochemical properties of Sm^(3+) doped Ca_(2)MgSi_(2)O_(7) nanophosphor:Display and electrochemical sensor applications 被引量:1
14
作者 R.B.Basavaraj K.Sureshkumar +6 位作者 D.P.Aarti M.B.Madhusudana Reddy G.Nagaraju T.Ramakrishnappa G.R.Navyashree K.R.Venkatesha Babu K.S.Hemalatha 《Journal of Rare Earths》 SCIE EI CAS CSCD 2024年第6期1046-1055,I0002,共11页
A series of orange-red light emitting Ca_(2)MgSi_(2)O_(7):Sm^(3+)nanopowders were fabricated via low-cost ecofriendly green combustion technique using Aloe vera gel as fuel.The phase purity of the samples were confirm... A series of orange-red light emitting Ca_(2)MgSi_(2)O_(7):Sm^(3+)nanopowders were fabricated via low-cost ecofriendly green combustion technique using Aloe vera gel as fuel.The phase purity of the samples were confirmed by the powder X-ray diffraction(PXRD)technique.Pure single-phase tetragonal structure is observed from the PXRD results with no additional impurity peaks.The band gap energy of the fabricated powders was estimated by diffuse reflectance spectra(DRS)and is found to be in the range of 4.01-5.98 eV.A high resolution scanning electron microscope(SEM)was used to study the morphological behaviour of the samples.Honeycomb-like structures are observed from the SEM results.The particle size was evaluated by transmission electron microscopy(TEM)and is found to be~50 nm.The interplanar distance is found to be 0.53 nm.Photoluminescence properties were systematically studied in detail.The phosphors are successfully excited at 403 nm NUV light,producing reddish-orange characteristic emission.The emission peaks are centered at 558(^(4)G_(5/2)→^(6)H_(5/2)),607(^(4)G_(5/2)→^(6)H_(7/2))and 645 nm(^(4)G_(5/2)→^(6)H_(9/2)),respectively.Among the observed peaks the red emanation(^(4)G_(5/2)→^(6)H_(7/2))is stronger than the orange emission(^(4)G_(5/2)→^(6)H_(5/2))in the current investigation.The photoluminescent concentration quenching is noticed above 5 mol%Sm^(3+)ion doping content.The dipole-dipole interaction resulting in cross relaxation is found to be the principal cause of concentration quenching mechanism.The color features such as Commission Internationale de I’Eclairage(CIE)and correlated color temperature(CCT)were studied in detail.The optimized chromaticity coordinates were estimated to be(0.6363,0.3632),which fall in the reddish-orange region.The average CCT value obtained is 3362 K.The average color purity is found to be~82%.Sm^(3+)incorporated Ca_(2)MgSi_(2)O_(7) samples are possible contender for single white light generation commercial candidates owing to their strong hypersensitivity of Sm^(3+)ions through host,least possibility for re-absorption of blue-green emission owing to poor direct f-f excitation of Sm^(3+)ions,and high color purity(reddish-orange emission).The prepared powders exhibit excellent electrochemical redox properties and CPE modified optimized powders show outstanding sensitive response which indicates its use in the potential electrochemical sensor materials for drug sensing studies. 展开更多
关键词 Green combustion PHOTOLUMINESCENCE Orange-red emission Color purity Sensors Rare earths
原文传递
Spatial-temporal evolution of vegetation evapotranspiration in Hebei Province,China 被引量:5
15
作者 WANG Qian-feng TANG Jia +6 位作者 ZENG Jing-yu QU Yan-ping ZHANG Qing SHUI Wei WANG Wu-lin YI Lin LENG Song 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第9期2107-2117,共11页
Evapotranspiration (ET) is the sum of soil or water body evaporation and plant transpiration from the earth surface and ocean to the atmosphere, and thus plays a significant role in regulating carbon and water resou... Evapotranspiration (ET) is the sum of soil or water body evaporation and plant transpiration from the earth surface and ocean to the atmosphere, and thus plays a significant role in regulating carbon and water resource cycles. The time-series data set from the remote sensing MOLDS product (MOD16) was used to study the spatial-temporal evolution of vegetation evapotranspiration in salinized areas during 2000-2014 by analyzing the variability, spatial patterns and Mann-Kendall (MK) nonparametric trends for the time series. The results indicate that inter-annual and intra-annual variations of ET across various vegetated areas show seasonal changes, with the abnormal months identified. The Cultivated land displays a greater degree of spatial heterogeneity and the spatial pattern of ET in the area covered by broadleaved deciduous forests corresponds to a higher ET rate and increased water consumption. Awidespread decline of ET is observed only in cultivated areas. However, agricultural cultivation doesn't worsen water shortage and soil salinization problems in the region, and water shortage problems are worsening for other vegetated areas. This research provides a basis of reference for the reasonable allocation of water resources and restructuring of vegetation patterns in salinized areas. 展开更多
关键词 EVAPOTRANSPIRATION Hebei Province MODIS spatial pattern VEGETATION spatial-temporal evolution
在线阅读 下载PDF
Paracrine factors for neurodegenerative disorders:special emphasis on Parkinson's disease
16
作者 Stefano Di Santo Hans Rudolf Widmer 《Neural Regeneration Research》 SCIE CAS CSCD 2016年第4期570-571,共2页
The progressive loss of dopaminergic neurons in the ventral mesencephalon is the main pathological hallmark of Parkinson’s disease(PD).Drugs currently available only alleviate the principal symptomatic motor-relate... The progressive loss of dopaminergic neurons in the ventral mesencephalon is the main pathological hallmark of Parkinson’s disease(PD).Drugs currently available only alleviate the principal symptomatic motor-related disturbances and their benefit is counteracted by side effects in the long time. 展开更多
关键词 Paracrine factors for neurodegenerative disorders ECM MSC
暂未订购
Aluminum Toxicity:A Case Study on Tobacco(Nicotiana tabacum L.) 被引量:1
17
作者 Munir Ozturk Mert Metin +10 位作者 Volkan Altay Tomonori Kawano Alvina Gul Bengu Turkyilmaz Unal Dilek Unal Rouf Ahmad Bhat Moonisa Aslam Dervash Kristina Toderich Esra Koc Pedro Garcia Caparros Andleeb Shahzadi 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第1期165-192,共28页
Aluminum is an abundant metal in the earth’s crust that turns out to be toxic in acidic environments.Many plants are affected by the presence of aluminum at the whole plant level,at the organ level,and at the cellula... Aluminum is an abundant metal in the earth’s crust that turns out to be toxic in acidic environments.Many plants are affected by the presence of aluminum at the whole plant level,at the organ level,and at the cellular level.Tobacco as a cash crop(Nicotiana tabacum L.)is a widely cultivated plant worldwide and is also a good model organism for research.Although there are many articles on Al-phytotoxicity in the literature,reviews on a single species that are economically and scientifically important are limited.In this article,we not only provide the biology associated with tobacco Al-toxicity,but also some essential information regarding the effects of this metal on other plant species(even animals).This review provides information on aluminum localization and uptake process by different staining techniques,as well as the effects of its toxicity at different compartment levels and the physiological consequences derived from them.In addition,molecular studies in recent years have reported specific responses to Al toxicity,such as overexpression of various protective proteins.Besides,this review discusses data on various organelle-based responses,cell death,and other mechanisms,data on tobacco plants and other kingdoms relevant to these studies. 展开更多
关键词 ALUMINUM oxidative stress protective proteins ROS TOBACCO TOXICITY
在线阅读 下载PDF
Crystal structure and luminescence dynamics of highly pure LiM(PO_(3))_(3):Eu^(3+)(M=Sr,Ca) red phosphors for white light emitting diodes
18
作者 Payal Khajuria M.Manhas +3 位作者 A.K.Bedyal Ankush Vij H.C.Swart Vinay Kumar 《Journal of Rare Earths》 SCIE EI CAS CSCD 2024年第8期1470-1478,I0002,共10页
Highly pure red phosphors LiM(PO_(3))_(3):Eu^(3+)(M=Sr,Ca) doped with Eu^(3+)(1 mol%) were synthesized via solution combustion method and their crystal structure and luminescence dynamics were studied to explore its s... Highly pure red phosphors LiM(PO_(3))_(3):Eu^(3+)(M=Sr,Ca) doped with Eu^(3+)(1 mol%) were synthesized via solution combustion method and their crystal structure and luminescence dynamics were studied to explore its suitability in white light emitting diodes.The Rietveld refinement analysis of the powder Xray diffraction patterns reveals that the phosphors belong to the pure triclinic phase of LiSr(PO_(3))_(3) and LiCa(PO_(3)) with space group P-1(2).The scanning electron microscopy images showed the agglomerated morphology.The photoluminescence emission spectra under 393 nm show an orange band at 594 nm and a red band at 613 nm ascribed to ^(5)D_(0)→^(7)F_(1).^(5)D_(0)→^(7)F_(2) transitions of Eu^(3+)ion in both the phosphors.Moreover,the spectroscopic properties such as luminescence behaviour,and Stark splitting were used to examine the symmetry of Eu^(3+)ions in LiM(PO_(3))_(3):Es^(3+)(M=Sr,Ca) phosphors in terms of distortion induced upon doping.The Stark splitting shows that the actual site symmetry for Eu^(3+)ion was estimated to be D_(2) type for both phosphors.The photometric properties of LiCa(PO_(3))_(3):Eu^(3+)such as Commission International de l'Eclairage coordinates(x=0.64,y=0.36) near to the standard one(red),high color purity(95%) and higher brightness reveal that the phosphor has the capability of acting as a red component in n-UV white light emitting diodes. 展开更多
关键词 Photoluminescence PHOSPHATE WLEDs Stark splitting Rare earths
原文传递
Gamma Irradiation Enhanced Leaf Bioactive Components and Bioassay Parameters in M<sub>5</sub>Mulberry (<i>Morus</i>Sp.) Mutant
19
作者 Hyadalu Lingappa Ramesh Lingenahalli Hosallappa Shivashankarappa Veerapura Narayanappa Yoganandamurthy 《American Journal of Plant Sciences》 2021年第12期1945-1962,共18页
Gamma radiation is an effective tool for inducing genetic variation in plant characters. In the present experiment, M<sub>5</sub> mulberry variety juvenile twigs were subjected to source Co<sup>60<... Gamma radiation is an effective tool for inducing genetic variation in plant characters. In the present experiment, M<sub>5</sub> mulberry variety juvenile twigs were subjected to source Co<sup>60</sup> gamma irradiation (1 kR - 10 kR)</span><span> </span><span style="font-family:"">and mutants grown in triplicates in randomized block design to raise M<sub>1</sub> and M<sub>2</sub><sup> </sup>generation. In M<sub>2</sub> generation plants were subjected to phytochemical and bioassay tests. Silkworm rearing parameters and commercial characters of cocoons were recorded by feeding cross breed silkworms. Results show that M<sub>5</sub> mutant leaves revealed significant variations in phytochemical constituents and moisture content. Bioassay tests recorded significant differences compared to control in M<sub>2</sub> generation. Commercial characters like cocoon weight (1.41 g), shell weight (0.24 g), shell percentage (16.29 %), filament length (821.00 mts), renditta (8.2), denier (2.24) and effective rate of rearing (92.14 %) were increased. It is concluded </span><span style="font-family:"">that, gamma rays treatment enhances the mulberry plants leaf </span><span style="font-family:"">bioactive components, silkworm rearing and cocoon parameters<b> </b>and shows beneficial variants in M<sub>2</sub> generation. 展开更多
关键词 BIOASSAY Cocoon Commercial Characters Gamma Rays Genotype Irradiation MULBERRY M5 Phytochemical
在线阅读 下载PDF
Organophosphine ligand derived sandwich-structural electrocatalyst for oxygen evolution reaction
20
作者 Zejun Sun Wenjuan Xu +8 位作者 Liutao Guo Qiang Han Jianyi Gao Jiaping Wang Yanru Feng Chengrui Li Qionglin Liang Hong-bin Sun Yang Yang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第7期74-83,I0003,共11页
The synchronous construction of metal phosphate and phosphorus-doped carbon structures is of great significance to innovate the design,synthesis,and application of catalysts,as these phosphoruscontaining composite mat... The synchronous construction of metal phosphate and phosphorus-doped carbon structures is of great significance to innovate the design,synthesis,and application of catalysts,as these phosphoruscontaining composite materials have shown a remarkable contribution to electrocatalysts.However,their preparation procedure generally involves using large amounts of excess phosphorus sources for phosphorization,which inevitably release poisonous PH_(3) or dangerous phosphorus vapor.Here,a strategy for in-situ formation of FePO_(4) embedded in P-doped carbon 2D nano film(FePO_(4)/PdC)is developed using a highly integrated precursor,which is a small molecular organophosphine ligand,1,1’bis(diphenylphosphine)ferrocene(DPPF).The multi-source precursor DPPF that contains Fe,P,and C is molecular-vapor-deposited on the nickel foam(NF)supported ZIF-67 nanosheets to obtain the composite catalyst,namely DPPF-500/ZIF-67/NF.FePO_(4)/PdC encapsulated the ZIF-67 derived Co/N-doped carbon matrix(Co NC)to form a sandwich structure FePO_(4)/PdC@CoNC.The constructed catalyst shows good performance for OER,requiring an overpotential of only 297 m V to deliver 600 m A/cm^(2) with a Tafel slope of 42.7 m V dec^(-1).DFT calculations demonstrate that the synergistic effects between the metal active center and P-doped carbon film reduce the energy barriers and improve electron transport.This method of constructing P-containing catalysts overcomes the demand for additional P sources to realize eco-friendly fabrication and yields a unique structure with good catalytic activity. 展开更多
关键词 Organophosphorus ligand Synchronous Synthesis FePO_(4) P-doped Carbon 2D nano film Oxygen evolution reaction
在线阅读 下载PDF
上一页 1 2 3 下一页 到第
使用帮助 返回顶部