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Book review “Wattles: Australian Acacia species around the world” by David M. Richardson, Johannes J. Le Roux and Elizabete Marchante
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作者 Klaus von Gadow 《Forest Ecosystems》 SCIE CSCD 2024年第2期140-141,共2页
In a world of Google and AI, developing an encyclopedic coverage of a theme that is of great interest to biologists, social scientists, politicians and environmental managers, is a daunting challenge. Wattles is a boo... In a world of Google and AI, developing an encyclopedic coverage of a theme that is of great interest to biologists, social scientists, politicians and environmental managers, is a daunting challenge. Wattles is a book that presents new knowledge, makes interesting reading, and has the potential to stimulate research in a variety of disciplines. We learn that Acacia, commonly known as the wattles or acacias, is a genus of shrubs and trees comprising 1,083 species of which 417 are known to have been introduced to areas outside their native range. We are surprised to read that Australian acacias are found almost everywhere, in virtually all terrestrial habitats, including woodlands, grasslands, alpine settings,rainforests, coastal dunes and deserts, causing major environmental and socio-economic changes in the invaded regions. Until recently, Acacia comprised a group of plant species native to Africa, South America and Australasia, but the name is now reserved for species predominantly from Australia, including some from Southeast Asia. The genus name Acacia is Neo-Latin, and refers to a preparation extracted from the leaves and fruit pods of Vachellia nilotica, the original type of the genus. 展开更多
关键词 RICHARDSON OUTSIDE LATIN
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Grouping tree species to estimate basal area increment in temperate multispecies forests in Durango,Mexico
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作者 Jaime Roberto Padilla-Martínez Carola Paul +2 位作者 Kai Husmann Jose Javier Corral-Rivas Klaus von Gadow 《Forest Ecosystems》 SCIE CSCD 2024年第1期1-13,共13页
Multispecies forests have received increased scientific attention,driven by the hypothesis that biodiversity improves ecological resilience.However,a greater species diversity presents challenges for forest management... Multispecies forests have received increased scientific attention,driven by the hypothesis that biodiversity improves ecological resilience.However,a greater species diversity presents challenges for forest management and research.Our study aims to develop basal area growth models for tree species cohorts.The analysis is based on a dataset of 423 permanent plots(2,500 m^(2))located in temperate forests in Durango,Mexico.First,we define tree species cohorts based on individual and neighborhood-based variables using a combination of principal component and cluster analyses.Then,we estimate the basal area increment of each cohort through the generalized additive model to describe the effect of tree size,competition,stand density and site quality.The principal component and cluster analyses assign a total of 37 tree species to eight cohorts that differed primarily with regard to the distribution of tree size and vertical position within the community.The generalized additive models provide satisfactory estimates of tree growth for the species cohorts,explaining between 19 and 53 percent of the total variation of basal area increment,and highlight the following results:i)most cohorts show a"rise-and-fall"effect of tree size on tree growth;ii)surprisingly,the competition index"basal area of larger trees"had showed a positive effect in four of the eight cohorts;iii)stand density had a negative effect on basal area increment,though the effect was minor in medium-and high-density stands,and iv)basal area growth was positively correlated with site quality except for an oak cohort.The developed species cohorts and growth models provide insight into their particular ecological features and growth patterns that may support the development of sustainable management strategies for temperate multispecies forests. 展开更多
关键词 Temperate multispecies forests Cluster analysis Basal area increment Generalized additive models
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Investigating Stability Properties for Transition Metal Carbonate Precursors Using Universal Cluster Expansion Technique(UNCLE)as Cathodes for Li-Ion Batteries
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作者 Mogahabo Tebogo Morukuladi N.L.Lethole +2 位作者 M.C.Masedi N.N.Ngoepe P.E.Ngoepe 《材料科学与工程(中英文A版)》 2024年第1期26-33,共8页
The universal cluster expansion technique was used in this study to determine the binary phase diagrams for the transition metal carbonate precursors MCO3(M:Mn,Ni,Co).The use of mixed cathode materials in lithium-ion ... The universal cluster expansion technique was used in this study to determine the binary phase diagrams for the transition metal carbonate precursors MCO3(M:Mn,Ni,Co).The use of mixed cathode materials in lithium-ion batteries such as NMC(Ni,Mn and Co)formulations,is a strategic approach to optimize performance,enhance safety and address cost and environmental considerations in the rapidly evolving field of energy storage.This study focuses on the cost issue related to lithium ion batteries by investigating the manganese rich NMC since manganese is more abundant and cost-effective.We doped MnCO3 with nickel and doped MnCO3 with cobalt then ran cluster expansion calculations to generate binary phases.The binary phase diagrams generated indicated that doping MnCO3 with nickel favours the Mn-rich side,while doping MnCO3 with cobalt favours 50%Mn-rich and 50%Co-rich.We further extracted the most stable structures from both binary diagrams and determined their electronic,mechanical and vibrational stabilities using DFT(density functional theory)calculations within the LDA(local gradient approximation)with Hubbard parameter(U).The electronic properties revealed that both materials are semiconductors due to their narrow energy band gap obtained while the mechanical properties showed that structures are mechanically stable since their necessary conditions for trigonal and triclinic systems were satisfied. 展开更多
关键词 Binary phase diagrams mechanical properties electronic conductivity phonon dispersion curves.
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Exploring the moderating role of financial development in environmental Kuznets curve for South Africa:fresh evidence from the novel dynamic ARDL simulations approach 被引量:2
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作者 Maxwell Chukwudi Udeagha Marthinus Christoffel Breitenbach 《Financial Innovation》 2023年第1期79-130,共52页
The extant literature has produced mixed evidence on the relationship between finan-cial development and ecological sustainability.This work addresses this conundrum by investigating financial development’s direct an... The extant literature has produced mixed evidence on the relationship between finan-cial development and ecological sustainability.This work addresses this conundrum by investigating financial development’s direct and indirect consequences on ecologi-cal quality utilizing the environmental Kuznets curve(EKC)methodological approach.Our empirical analysis is based on the novel dynamic autoregressive distributed lag simulations approach for South Africa between 1960 and 2020.The results,which used five distinct financial development measures,demonstrate that financial develop-ment boosts ecological integrity and environmental sustainability over the long and short terms.In the instance of South Africa,we additionally confirm the validity of the EKC theory.More importantly,the outcomes of the indirect channels demonstrate that financial development increases energy usage’s role in causing pollution while attenuating the detrimental impacts of economic growth,trade openness,and foreign direct investment on ecological quality.Moreover,the presence of an inadequate financial system is a requirement for the basis of the pollution haven hypothesis(PHH),which we examine using trade openness and foreign direct investment variables.PHH for both of these variables disappears when financial development crosses specified thresholds.Finally,industrial value addition destroys ecological quality while tech-nological innovation enhances it.This research provides some crucial policy recom-mendations and fresh perspectives for South Africa as it develops national initiatives to support ecological sustainability and reach its net zero emissions goal. 展开更多
关键词 Financial development Trade openness CO_(2)emissions Dynamic ARDL simulations Energy consumption EKC COINTEGRATION Economic growth Foreign direct investment Industrial value-added South Africa
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Revisiting the nexus between fiscal decentralization and CO_(2)emissions in South Africa:fresh policy insights 被引量:1
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作者 Maxwell Chukwudi Udeagha Marthinus Christoffel Breitenbach 《Financial Innovation》 2023年第1期1384-1429,共46页
The argument over fiscal decentralization and carbon dioxide emission(CO_(2))reduction has received much attention.However,evidence to back this claim is limited.Economic theory predicts that fiscal decentralization a... The argument over fiscal decentralization and carbon dioxide emission(CO_(2))reduction has received much attention.However,evidence to back this claim is limited.Economic theory predicts that fiscal decentralization affects environmental quality,but the specifics of this relationship are still up for debate.Some scholars noted that fiscal decentralization might lead to a race to the top,whereas others contended that it would result in a race to the bottom.In light of the current debates in environmental and development economics,this study aims to provide insight into how this relationship may function in South Africa from 1960 to 2020.In contrast to the existing research,the present study uses a novel dynamic autoregressive distributed lag simulation approach to assess the positive and negative changes in fiscal decentralization,scale effect,technique effect,technological innovation,foreign direct investment,energy consumption,industrial growth,and trade openness on CO_(2)emissions.The following are the main findings:(i)Fiscal decentralization had a CO_(2)emission reduction impact in the short and long run,highlighting the presence of the race to the top approach.(ii)Economic growth(as represented by the scale effect)eroded ecological integrity.However,its square(as expressed by technique effect)aided in strengthening ecological protection,validating the environmental Kuznets curve hypothesis.(iii)CO_(2)emissions were driven by energy utilization,trade openness,industrial value-added,and foreign direct investment,whereas technological innovation boosted ecological integrity.Findings suggest that further fiscal decentralization should be undertaken through further devolution of power to local entities,particularly regarding environmental policy issues,to maintain South Africa’s ecological sustainability.South Africa should also establish policies to improve environmental sustainability by strengthening a lower layer of government and clarifying responsibilities at the national and local levels to fulfill the energy-saving functions of fiscal expenditures. 展开更多
关键词 Fiscal decentralization Trade openness CO_(2)emissions Dynamic ARDL simulations Energy consumption EKC COINTEGRATION Economic growth Industrial value-added South Africa
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Matrix integrable fifth-order mKdV equations and their soliton solutions 被引量:2
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作者 马文秀 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第2期47-52,共6页
We consider matrix integrable fifth-order mKdV equations via a kind of group reductions of the Ablowitz–Kaup–Newell–Segur matrix spectral problems. Based on properties of eigenvalue and adjoint eigenvalue problems,... We consider matrix integrable fifth-order mKdV equations via a kind of group reductions of the Ablowitz–Kaup–Newell–Segur matrix spectral problems. Based on properties of eigenvalue and adjoint eigenvalue problems, we solve the corresponding Riemann–Hilbert problems, where eigenvalues could equal adjoint eigenvalues, and construct their soliton solutions, when there are zero reflection coefficients. Illustrative examples of scalar and two-component integrable fifthorder mKdV equations are given. 展开更多
关键词 matrix integrable equation Riemann–Hilbert problem SOLITON
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A new hybrid method with data‑characteristic‑driven analysis for artificial intelligence and robotics index return forecasting
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作者 Yue‑Jun Zhang Han Zhang Rangan Gupta 《Financial Innovation》 2023年第1期2019-2041,共23页
Forecasting returns for the Artificial Intelligence and Robotics Index is of great significance for financial market stability,and the development of the artificial intelligence industry.To provide investors with a mo... Forecasting returns for the Artificial Intelligence and Robotics Index is of great significance for financial market stability,and the development of the artificial intelligence industry.To provide investors with a more reliable reference in terms of artificial intelligence index investment,this paper selects the NASDAQ CTA Artificial Intelligence and Robotics(AIRO)Index as the research target,and proposes innovative hybrid methods to forecast returns by considering its multiple structural characteristics.Specifically,this paper uses the ensemble empirical mode decomposition(EEMD)method and the modified iterative cumulative sum of squares(ICSS)algorithm to decompose the index returns and identify the structural breakpoints.Furthermore,it combines the least-square support vector machine approach with the particle swarm optimization method(PSO-LSSVM)and the generalized autoregressive conditional heteroskedasticity(GARCH)type models to construct innovative hybrid forecasting methods.On the one hand,the empirical results indicate that the AIRO index returns have complex structural characteristics,and present time-varying and nonlinear characteristics with high complexity and mutability;on the other hand,the newly proposed hybrid forecasting method(i.e.,the EEMD-PSO-LSSVM-ICSS-GARCH models)which considers these complex structural characteristics,can yield the optimal forecasting performance for the AIRO index returns. 展开更多
关键词 Artificial Intelligence and Robotics index return forecasting PSO-LSSVM model GARCH model Decomposition and integration model Combination model
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Prioritised identification of structural classes of natural products from higher plants in the expedition of antimalarial drug discovery
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作者 Phanankosi Moyo Luke Invernizzi +5 位作者 Sephora M.Mianda Wiehan Rudolph Andrew W.Andayi Mingxun Wang Neil R.Crouch Vinesh J.Maharaj 《Natural Products and Bioprospecting》 CSCD 2023年第1期348-367,共20页
The emergence and spread of drug-recalcitrant Plasmodium falciparum parasites threaten to reverse the gains made in the fight against malaria.Urgent measures need to be taken to curb this impending challenge.The highe... The emergence and spread of drug-recalcitrant Plasmodium falciparum parasites threaten to reverse the gains made in the fight against malaria.Urgent measures need to be taken to curb this impending challenge.The higher plant-derived sesquiterpene,quinoline alkaloids,and naphthoquinone natural product classes of compounds have previously served as phenomenal chemical scaffolds from which integral antimalarial drugs were developed.Historical successes serve as an inspiration for the continued investigation of plant-derived natural products compounds in search of novel molecular templates from which new antimalarial drugs could be developed.The aim of this study was to identify potential chemical scaffolds for malaria drug discovery following analysis of historical data on phytochemicals screened in vitro against P.falciparum.To identify these novel scaffolds,we queried an in-house manually curated database of plant-derived natural product compounds and their in vitro biological data.Natural products were assigned to different structural classes using NPClassifier.To identify the most promising chemical scaffolds,we then correlated natural compound class with bioactivity and other data,namely(i)potency,(ii)resistance index,(iii)selectivity index and(iv)physicochemical properties.We used an unbiased scoring system to rank the different natural product classes based on the assessment of their bioactivity data.From this analysis we identified the top-ranked natural product pathway as the alkaloids.The top three ranked super classes identified were(i)pseudoalkaloids,(ii)naphthalenes and(iii)tyrosine alkaloids and the top five ranked classes(i)quassinoids(of super class triterpenoids),(ii)steroidal alkaloids(of super class pseudoalkaloids)(iii)cycloeudesmane sesquiterpenoids(of super class triterpenoids)(iv)isoquinoline alkaloids(of super class tyrosine alkaloids)and(v)naphthoquinones(of super class naphthalenes).Launched chemical space of these identified classes of compounds was,by and large,distinct from that of‘legacy’antimalarial drugs.Our study was able to identify chemical scaffolds with acceptable biological properties that are structurally different from current and previously used antimalarial drugs.These molecules have the potential to be developed into new antimalarial drugs. 展开更多
关键词 Natural products Compound classes PHYTOCHEMICALS Plasmodium falciparum Antiplasmodial drug resistance MALARIA Drug development
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Cross-correlation Forecast of CSST Spectroscopic Galaxy and MeerKAT Neutral Hydrogen Intensity Mapping Surveys
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作者 Yu-Er Jiang Yan Gong +6 位作者 Meng Zhang Qi Xiong Xingchen Zhou Furen Deng Xuelei Chen Yin-Zhe Ma Bin Yue 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第7期25-36,共12页
Cross-correlating the data on neutral hydrogen(HⅠ)21 cm intensity mapping with galaxy surveys is an effective method to extract astrophysical and cosmological information.In this work,we investigate the cross-correla... Cross-correlating the data on neutral hydrogen(HⅠ)21 cm intensity mapping with galaxy surveys is an effective method to extract astrophysical and cosmological information.In this work,we investigate the cross-correlation of MeerKAT single-dish mode HⅠintensity mapping and China Space Station Telescope(CSST)spectroscopic galaxy surveys.We simulate a survey area of~300 deg~2 of MeerKAT and CSST surveys at z=0.5 using MultiDark N-body simulation.The PC A algorithm is applied to remove the foregrounds of HⅠintensity mapping,and signal compensation is considered to solve the signal loss problem in HⅠ-galaxy cross power spectrum caused by the foreground removal process.We find that from CSST galaxy auto and MeerKAT-CSST cross power spectra,the constraint accuracy of the parameter productΩ_(HⅠ)b_(HⅠ)r_(HⅠ,g)can reach~1%,which is about one order of magnitude higher than the current results.After performing the full MeerKAT HⅠintensity mapping survey with5000 deg~2 survey area,the accuracy can be enhanced to<0.3%.This implies that the MeerKAT-CSST cross-correlation can be a powerful tool to probe the cosmic HⅠproperty and the evolution of galaxies and the Universe. 展开更多
关键词 (cosmology:)large-scale structure of universe (cosmology:)cosmological parameters COSMOLOGY
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Classifying moisture sources associated with snowfall in the mountains of Lesotho
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作者 Alexi M.MARINAKI Jennifer M.FITCHETT 《Journal of Mountain Science》 SCIE CSCD 2024年第6期1941-1953,共13页
An average of eight snowfall events occur each year in the eastern Lesotho Highlands.These snowfall events are typically associated with cut-off low(CoLs)systems and mid-latitude cyclones.However,the moisture sources ... An average of eight snowfall events occur each year in the eastern Lesotho Highlands.These snowfall events are typically associated with cut-off low(CoLs)systems and mid-latitude cyclones.However,the moisture sources of the snowfall are unclassified and unclear.The Hybrid Single-Particle Lagrangian Integrated Trajectory(HYSPLIT)model,an air mass back trajectory model,has been used to evaluate moisture source waters locally in southern Africa and internationally in China and Europe.This study uses HYSPLIT to determine the source moisture of snow in Lesotho.A list of all 82 snowfall events in Lesotho spanning 2017 to 2022 was compiled using the Snow Report SA Instagram page,including the date and location of snowfall.A 72-hour back trajectory for each snowfall event was initiated for both Afriski and the whole of Lesotho.This amounts to models of moisture source trajectories for 28 and 82 snowfall days,respectively.These air mass pathways are classified according to their frequency per snowfall event,per month in the snow season,per year and for the full period.From this,associated moisture source regions and dominant air mass trajectories were identified.This study reports that the air mass trajectories associated with Afriski and Lesotho as a whole are very similar.The most common pathway of air mass trajectories transporting snow-bearing moisture to Lesotho was an inland trajectory from the northern regions of southern Africa.This pathway makes up 16.6%of all trajectories reported and is associated with the Angola Low,the Congo Air Boundary and the St.Helena High Pressure. 展开更多
关键词 Eastern Lesotho Highlands Afriski SNOW Cut-off Lows HYSPLIT Synoptic Climatology
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High level arsenic resistance in bacteria present in biooxidation tanks used to treat gold-bearing arsenopyrite concentrates:A review 被引量:9
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作者 D.E.RAWLINGS 《中国有色金属学会会刊:英文版》 EI CSCD 2008年第6期1311-1318,共8页
在连续流动的、搅动的坦克过程使用到金忍受的毒砂集中的对待的微生物引起的协会变得在很多年适应了砷的高集中。主导的微生物, Acidithiobacillus caldus 和 Leptospirillum ferriphilum,被发现包含砷抵抗基因的二个集合。艺术基因... 在连续流动的、搅动的坦克过程使用到金忍受的毒砂集中的对待的微生物引起的协会变得在很多年适应了砷的高集中。主导的微生物, Acidithiobacillus caldus 和 Leptospirillum ferriphilum,被发现包含砷抵抗基因的二个集合。艺术基因的一个集合在所有是在场的不管他们是否是,种孤立高度砷抵抗。艺术基因的第二个集合在象 Tn21 一样 transposons 上是在场的并且在测试的所有紧张被发现那被使适应了砷的高集中。在在场的砷抵抗 transposons 在。caldus 和 L。ferriphilum 为他们密切相关,却足够地不同独立地被获得了而非从一个细菌被传递了给其它。transposons 在 Escherchia coli 是置换地活跃的并且被显示比测试这是可能的定位 chromosomally 的艺术基因授与砷抵抗的高水平。相同的 Transposons 包含砷抵抗基因或仔细与从 L 的 transposon 有关。ferriphilum,原来在南非发现,也在两 L 被发现。ferrooxidans 和 L。ferriphilum 从南美洲和欧洲孤立。一个 arsB 基因大美人在。caldus 被两个都表明了 chromosomal 艺术基因的能力授与砷抵抗的底层在的相应再结合生产在。caldus 和为猛烈异种的创造的一个基因系统的发展。 展开更多
关键词 砷电阻因子 转座子 微生物 毒砂
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MHD flow of upper-convected Maxwell fluid over porous stretching sheet using successive Taylor series linearization method 被引量:3
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作者 S.S.MOTSA T.HAYAT O.M.ALDOSSARY 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2012年第8期975-990,共16页
This paper investigates the magnetohydrodynamic (MHD) boundary layer flow of an incompressible upper-convected Maxwell (UCM) fluid over a porous stretching surface. Similarity transformations are used to reduce th... This paper investigates the magnetohydrodynamic (MHD) boundary layer flow of an incompressible upper-convected Maxwell (UCM) fluid over a porous stretching surface. Similarity transformations are used to reduce the governing partial differential equations into a kind of nonlinear ordinary differential equations. The nonlinear prob- lem is solved by using the successive Taylor series linearization method (STSLM). The computations for velocity components are carried out for the emerging parameters. The numerical values of the skin friction coefficient are presented and analyzed for various parameters of interest in the problem. 展开更多
关键词 upper-convected Maxwell (UCM) fluid boundary layer flow successivelinearization method successive Taylor series linearization method (STSLM)
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Experimental evaluation of activated carbon derived from South Africa discard coal for natural gas storage 被引量:2
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作者 Jibril Abdulsalam Jean Mulopo +2 位作者 Bilainu Oboirien Samson Bada Rosemary Falcon 《International Journal of Coal Science & Technology》 EI 2019年第3期459-477,共19页
Lacking in literature is the use of discard coal to produce activated carbon and in its subsequent use in the storage of natural gas. In this study, the characterization and gas storage evaluation of a largely porous ... Lacking in literature is the use of discard coal to produce activated carbon and in its subsequent use in the storage of natural gas. In this study, the characterization and gas storage evaluation of a largely porous activated carbon with large surface area synthesized from discard coal were investigated. Discard coals are waste material generated from coal beneficiation process. In developing the activated carbon, chemical activation route with the use of KOH reagent was applied. The effects of KOH/discard coal weight ratio (1:1, 2.5:1, 4:1), temperature (400-800 ℃) and particle size (0.15-0.25 mm, 0.25-0.5 mm, 0.5-1 mm) on the adsorptive properties of the activated carbon were methodically evaluated and optimized using response surface methodology. The synthesized activated carbon was characterized using BET, SEM/EDS, and XRD. The results showed that for each activation process, the surface area and pore volume of the resulting activated carbon increased with increased temperature and KOH/discard coal weight ratio. The maximum surface area of 1826.41 m2/g, pore volume of 1.252 cm^3/g and pore size of 2.77 nm were obtained at carbonization temperature of 800 ℃ and KOH/discard coal weight ratio of 4:1. Methane and nitrogen adsorption data at high pressure were fitted to Toth isotherm model with a predictive accuracy of about 99%. Adsorption parameters using the Toth model provides useful information in the design of adsorbed natural gas storage system. According to the requirements of adsorbent desired for natural gas storage, it could be stated that the synthesized activated carbon could well be applied for natural gas storage. 展开更多
关键词 DISCARD COAL ACTIVATED carbon Surface area METHANE ADSORPTION
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Modelling and thermodynamic properties of pure CO_(2)and fue gas sorption data on South African coals using Langmuir,Freundlich,Temkin,and extended Langmuir isotherm models 被引量:3
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作者 Major Mabuza Kasturie Premlall Michael O.Daramola 《International Journal of Coal Science & Technology》 EI CAS CSCD 2022年第3期136-150,共15页
Carbon sequestration in unmineable coal seams has been proposed as one of the most attractive technologies to mitigate carbon dioxide(CO_(2))emissions in which CO_(2)is stored in the microporous structure of the coal ... Carbon sequestration in unmineable coal seams has been proposed as one of the most attractive technologies to mitigate carbon dioxide(CO_(2))emissions in which CO_(2)is stored in the microporous structure of the coal matrix in an adsorbed state.The CO_(2)adsorption process is hence considered one of the more efective methodologies in environmental sciences.Thus,adsorption isotherm measurements and modelling are key important scientifc measures required in understanding the adsorption system,mechanism,and process optimization in coalbeds.In this paper,three renowned and reliable adsorption isotherm models were employed including Langmuir,Freundlich,and Temkin for pure CO_(2)adsorption data,and the extended-Langmuir model for multicomponent,such as fue gas mixture-adsorption data as investigated in this research work.Also,signifcant thermodynamics properties including the standard enthalpy change(ΔH°),entropy change(ΔS°),and Gibbs free energy(ΔG°)were assessed using the van’t Hof equation.The statistical evaluation of the goodness-of-ft was done using three(3)statistical data analysis methods including correlation coefcient(R^(2)),standard deviation(σ),and standard error(SE).The Langmuir isotherm model accurately represent the pure CO_(2)adsorption on the coals than Freundlich and Temkin.The extended Langmuir gives best experimental data ft for the fue gas.The thermodynamic evaluations revealed that CO_(2)adsorption on the South African coals is feasible,spontaneous,and exothermic;and the adsorption mechanism is a combined physical and chemical interaction between the adsorbate and the adsorbent. 展开更多
关键词 Global warming Flue gas Adsorption Unmineable coal Adsorption models
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Continuous Fabrication of Ti_(3)C_(2)T_x MXene-Based Braided Coaxial Zinc-Ion Hybrid Supercapacitors with Improved Performance 被引量:4
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作者 Bao Shi La Li +3 位作者 Aibing Chen Tien-Chien Jen Xinying Liu Guozhen Shen 《Nano-Micro Letters》 SCIE EI CAS CSCD 2022年第2期206-215,共10页
Zinc-ion hybrid fiber supercapacitors(FSCs)are promising energy storages for wearable electronics owing to their high energy density,good flexibility,and weavability.However,it is still a critical challenge to optimiz... Zinc-ion hybrid fiber supercapacitors(FSCs)are promising energy storages for wearable electronics owing to their high energy density,good flexibility,and weavability.However,it is still a critical challenge to optimize the structure of the designed FSC to improve energy density and realize the continuous fabrication of super-long FSCs.Herein,we propose a braided coaxial zinc-ion hybrid FSC with several meters of Ti_(3)C_(2)T_x MXene cathode as core electrodes,and shell zinc fiber anode was braided on the surface of the Ti_(3)C_(2)T_x MXene fibers across the solid electrolytes.According to the simulated results using ANSYS Maxwell software,the braided structures revealed a higher capacitance compared to the spring-like structures.The resulting FSCs exhibited a high areal capacitance of 214 mF cm^(-2),the energy density of 42.8μWh cm^(-2)at 5 mV s^(-1),and excellent cycling stability with 83.58%capacity retention after 5000 cycles.The coaxial FSC was tied several kinds of knots,proving a shape-controllable fiber energy storage.Furthermore,the knitted FSC showed superior stability and weavability,which can be woven into watch belts or embedded into textiles to power smart watches and LED arrays for a few days. 展开更多
关键词 Ti_(3)C_(2)T_x MXene Fiber supercapacitor Coaxial structure Zinc-ion
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Evidence for Mesoproterozoic collision,deep burial and rapid exhumation of garbenschiefer in the Namaqua Front,South Africa 被引量:3
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作者 Valby Van Schijndel David HCornell +1 位作者 Robert Anczkiewicz Anders Schersten 《Geoscience Frontiers》 SCIE CAS CSCD 2020年第2期511-531,共21页
Metamorphic provinces such as the^1 Ga Grenvillian,~400 Ma Caledonide and Triassic Qinling Provinces often contain rocks with high-pressure assemblages such as eclogites,which formed at mantle depths in subduction zon... Metamorphic provinces such as the^1 Ga Grenvillian,~400 Ma Caledonide and Triassic Qinling Provinces often contain rocks with high-pressure assemblages such as eclogites,which formed at mantle depths in subduction zones.These are evidence of the accretion of terranes by subduction of oceans and collision to form large tectonostratigraphic provinces.The Mesoproterozoic Namaqua-Natal Province comprises a number of terranes thought to have been assembled by plate-tectonic processes,but they have generally yielded metamorphic pressures below 5 kbar,corresponding to<20 km,crustal depths,lacking evidence for subduction processes.The Kaaien Terrane in the Namaqua Front contains two large garbenschiefer units with the unusual paragenesis garnet-hornblende-epidote-white mica-plagioclase-ilmenite-quartz.Their protoliths are graywackes influenced by andesitic volcanism during their deposition at^1870 Ma,in a passive margin of the Rehoboth Province or Kaapvaal Craton.Prograde garnet growth dated at 11655 Ma culminated in peak metamorphic conditions of 64530C and 10.40.7 kbar,corresponding to 40 km depth.This is attributed to subduction of these rocks before collision between the overriding arc-related Areachap Terrane,the Kaaien Terrane and the Kaapvaal-Rehoboth cratonic block during the Namaqua orogeny.Exhumation of the garbenschiefer slabs was followed by rapid cooling,as the 11435 Ma argon dates of hornblende and white mica,with closure temperatures^540C and^440C respectively,are the same within error.This was probably due to tectonic juxtaposition of the garbenschiefer slab with much cooler rock units.The exhumation was accommodated along the Trooilapspan-Brakbosch Shear Zone due to ongoing transpression.Other components of the Namaqua Front have distinctly different P-T-t paths,exemplified by greenschist metamorphism in the 1300 Ma Wilgenhoutsdrift Group,and medium-pressure metamorphism in the Areachap Terrane.They were juxtaposed by late-tectonic uplift and transpressional movements.The^40 km depth of garbenschiefer peak metamorphism is the deepest yet found in the Namaqua-Natal Province and strengthens the plate tectonic model of accretion by collision of terranes at the end of a Wilson cycle.The high pressure paragenesis of the garbenschiefer was preserved due to its location in the Namaqua Front,whereas most other parts of the Namaqua-Natal Province were overprinted by 1100–1020 Ma thermal events after the collision events. 展开更多
关键词 Collision orogeny P-T-t path Garbenschiefer Lu–Hf garnet U–Pb zircon 40Ar/39Ar dating
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Antioxidant, antibacterial and phytochemical properties of two medicinal plants against the wound infecting bacteria 被引量:1
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作者 Idowu Jonas Sagbo Anthony Jide Afolayan Graeme Bradley 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2017年第9期817-825,共9页
Objective: To investigate the antioxidant, antibacterial and phytochemical properties of ethanol extracts of Brachylaena elliptica and Brachylaena ilicifolia against wound infecting bacteria normally found in diabetic... Objective: To investigate the antioxidant, antibacterial and phytochemical properties of ethanol extracts of Brachylaena elliptica and Brachylaena ilicifolia against wound infecting bacteria normally found in diabetic patients.Methods: The in vitro antioxidant activity of the two plants extracts were investigated spectrophotometrically using 1,1-diphenyl-2-picrylhydrazyl, nitric oxide, azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) diammonium salt, hydrogen peroxide(H_2O_2) and ferric reducing power. The antibacterial assay and minimum inhibitory concentration(MIC) was determined using the agar dilution method against five bacteria strains using amoxycillin and ciprofloxacin as positive control. The phytochemical analyses(tannins,total phenol, flavonoids, flavonols, proanthocyanidin, alkaloids and saponins) were assessed using standard methods.Results: The ethanol extract of both plants exhibited strong antioxidant activities in some cases when compared to the standards(vitamin C and BHT). The antibacterial activity of both plants showed an appreciable broad spectrum activity against these wound pathogens with MIC value ranges between 0.3 mg/m L and 5 mg/m L. Tannins,phenols, flavanols, proanthocyanidins and alkaloids content of B. ilicifolia were significantly higher than those in B. elliptica. However, there were no significant differences in the flavanoid content of both plants extracts.Conclusions: These results indicated that the ethanol leaf extracts of these plants have antioxidant and antibacterial activity against the tested bacteria possibly due to the presence of bioactive compounds and therefore could be used as alternative therapy against wound infection caused by these bacteria in diabetic patients. 展开更多
关键词 Diabetes mellitus ANTIOXIDANT PHYTOCHEMICAL Brachylaena elliptica Brachylaena ilicifolia WOUND
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Traditional usage,phytochemistry and pharmacology of Croton sylvaticus Hochst.ex C.Krauss 被引量:1
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作者 Alfred Maroyi 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2017年第5期401-407,共7页
Croton sylvaticus(C. sylvaticus) is widely used as herbal medicine by the indigenous people of tropical Africa. The potential of C. sylvaticus as herbal medicine,the phytochemistry and pharmacological properties of it... Croton sylvaticus(C. sylvaticus) is widely used as herbal medicine by the indigenous people of tropical Africa. The potential of C. sylvaticus as herbal medicine,the phytochemistry and pharmacological properties of its parts used as herbal medicines are reviewed. The extensive literature survey revealed that C. sylvaticus is traditionally used to treat or manage at least 24 human and animal diseases and ailments. The species is used as herbal medicine for diseases and ailments such as abdominal pains,boils,fever,inflammation,malaria,rheumatism,swellings and tuberculosis and as ethnoveterinary medicine. Multiple classes of phytochemicals such as alkaloids,anthraquinones,essential oils,flavonoids,lignan,phenolics,sterols,tannins and terpenoids have been isolated from the species. Scientific studies on C. sylvaticus indicate that it has a wide range of pharmacological activities which include antibacterial,antifungal,anti-inflammatory,antioxidant,larvicidal and effects on the central nervous system. Although studies have confirmed that C. sylvaticus has a wide range of bioactives,further research on the exact bioactive molecules and mechanisms of action are required. 展开更多
关键词 AFRICA Croton sylvaticus ETHNOPHARMACOLOGY EUPHORBIACEAE Indigenous knowledge Traditional uses
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Postharvest physiological responses of pomegranate fruit (cv. Wonderful) to exogenous putrescine treatment and effects on physico-chemical and phytochemical properties 被引量:2
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作者 Olaniyi Amos Fawole Julian Atukuri +1 位作者 Ebrahiema Arendse Umezuruike Obia Opara 《Food Science and Human Wellness》 SCIE 2020年第2期146-161,共16页
Pomegranate fruit(cv.Wonderful)were treated with putrescine(1,2 and 3 mmol/L)before storage for 4 months at 5℃ and 95%RH and the effects on postharvest life and quality attributes were studied.Results showed that inc... Pomegranate fruit(cv.Wonderful)were treated with putrescine(1,2 and 3 mmol/L)before storage for 4 months at 5℃ and 95%RH and the effects on postharvest life and quality attributes were studied.Results showed that incidence of physiological disorders such as external decay,husk scald,chilling injury and aril browning increased with progressive storage but treating pomegranate fruit with putrescine reduced incidence of most disorders.Control fruit had higher levels of external decay(1.72%–33.26%),chilling injury(10.53%–38.77%)and scalding(15.04%–100%)with less attractive color during 4 month storage.Variations were observed on other fruit quality parameters although treatment with putrescine at 2 and 3 mmol/L concentration reduced changes in color,total soluble solid,Titratable acidity and ascorbic acid.Sensory parameters were best preserved in fruit treated with 2 mmol/L concentration of putrescine with respect to juiciness and crispness.Treatment of pomegranate fruit with putrescine resulted in improved storability and fruit quality during storage.Therefore,for short term storage,2 mmol/L concentration of putrescine could be recommended for maintaining fruit quality especially in the first two months of storage.However,for longer storage period,a higher concentration is recommended,as 3 mmol/L concentration was the most effective in alleviating disorders and maintaining physico-chemical parameters and sensory attributes during storage in this study. 展开更多
关键词 Decay Chilling injury PHYTOCHEMICAL Sensory properties Principal component analysis
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Matrix Integrable Fourth-Order Nonlinear Schr?dinger Equations and Their Exact Soliton Solutions 被引量:2
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作者 Wen-Xiu Ma 《Chinese Physics Letters》 SCIE EI CAS CSCD 2022年第10期1-6,共6页
We construct matrix integrable fourth-order nonlinear Schrödinger equations through reducing the Ablowitz-Kaup-Newell-Segur matrix eigenvalue problems.Based on properties of eigenvalue and adjoint eigenvalue prob... We construct matrix integrable fourth-order nonlinear Schrödinger equations through reducing the Ablowitz-Kaup-Newell-Segur matrix eigenvalue problems.Based on properties of eigenvalue and adjoint eigenvalue problems,we solve the corresponding reflectionless Riemann-Hilbert problems,where eigenvalues could equal adjoint eigenvalues,and formulate their soliton solutions via those reflectionless Riemann-Hilbert problems.Soliton solutions are computed for three illustrative examples of scalar and two-component integrable fourth-order nonlinear Schrödinger equations. 展开更多
关键词 EIGENVALUE INTEGRABLE ADJOINT
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