检索结果-南通市图书馆

China’s Transformative Approach to Africa——Sino-Angolan Relations as A Case Study(1983-2019)

在线全文

学校读者我要写书评

暂无评论

China’s Transformative Approach to Africa——Sino-Angolan R...

作者： roberto dos santos 山东大学

学位级别：硕士

The main purpose of this thesis is to analyse these recent historical,and transformative,relations between Angola and China as a useful case study that can synthesize and be used as a standard case to explain the development of this transformative and close commercial and trade relations between China and Africa in the 21st *** dependent variable for the research will be the diplomatic missions,events and deals between China and Angola during the time frame that I established for the study;while the independent variable will be the domestic events and domestic political concerns of the respective countries,combined with the geopolitical transformations that occurred throughout the years that determined the course of the relations between China and Angola,and how that translates to a larger geopolitical *** real aspect of this dissertation begins with a brief historical contextualization towards Angola-Chinese relations after both countries officially established diplomatic relations in 12 January 1983,until the 2002,when the civil war in Angola had officially *** the strengthen of economic cooperation between the two countries,we will investigate on the reasons,the dynamics,and factors that contributed to the creation of a channel of Chinese financial assistance to Angola through the offering of credit lines in the form of infrastructure projects,and how those funds were used by Angola for its post-war ***,this dissertation also focuses on how China,through its policy of investments and financial assistance,exchange it for Angola’s oil and other natural resources in the form of a cooperative exchange that serves both interests *** author chose the specific chronological arc（1983-2019）,to make a synthesis of what was the Sino-Angolan bilateral relations during those early years until *** period provides the opportunity to analyse and understand of how the People’s Republic of China after the rise of p

关键词：

Old climatically-buffered infertile landscapes(OCBILs):more than harsh habitats,Atlantic Forest inselbergs can be drivers of evolutionary diversity

同方学位论文库评论

在线全文

同方学位论文库

学校读者我要写书评

暂无评论

Journal of Mountain Science 2022年第9期19卷 2528-2543页

作者： Felipe de CARVALHO ARAÚJO Natália de aguiar-CAMPOS Cleber Rodrigo de SOUZA Eduardo de Paiva PAULA Rubens Manoel dos santos Laboratory of Phytogeography and Evolutionary Ecology Department of Forest SciencesFederal University of LavrasLavrasMinas GeraisBrazil

Granite-gneiss rock outcrop inselbergs are ancient stable ecosystems with old,climaticallybuffered infertile landscapes(OCBILs).Although inselbergs provide key ecosystem services,little is done for their conservation and,so far,a lot of their unknown evolutionary history has already been lost by human *** a fine-scale approach,here we tested if habitat and environmental filtering(the inselberg’s harshness)affect the evolutionary diversity of an Atlantic Forest inselberg in *** recorded all trees with a diameter at breast height≥5cm in 20 plots in four habitat types(total sampled area of 0.8 hectares),from highest to lowest:island,hillside,foothill,and semideciduous forest(matrix).We also collected soil samples for chemical,textural and physical soil *** fitted linear models to test the effects of soil and habitat on plotlevel metrics of phylogenetic diversity and structure,lineage diversity,phylogeneticβ-diversity,and evolutionary *** found that the upper inselberg habitats contain a distinct set of ancient,closely related,harsh-tolerant lineages,as well as a subset of lineages that persist under harsh conditions with a certain degree of water *** inferior inselberg habitats harbor higher lineage diversity than expected by *** strongly predicted evolutionary *** concluded that soil depth,slope,nutrients and texture(environmental filtering)and habitat types and topography(habitat filtering)shape the evolutionary history contained in fine-scale inselberg habitats,which should encourage the conservation of these ancient ecosystems.

关键词： Phylogenetic diversity Atlantic Forest Niche conservatism Environmental filters Soil fertility Terrestrial Island

Capacitorless Solid-state Power Filter for Single-phase DC-AC Converters

在线全文

学校读者我要写书评

暂无评论

CES Transactions on Electrical Machines and Systems 2024年第3期8卷 367-377页

作者： Haitham Kanakri Euzeli C.dos santos Purdue University Electrical and Computer Engineering DepartmentIndianapolisIN46202 USA

Converters rely on passive filtering as a crucial element due to the high-frequency operational characteristics of power *** filtering methods involve a dual inductor-capacitor(LC)cell or an inductor-capacitor-inductor(LCL)***,capacitors are susceptible to wear-out mechanisms and failure ***,the necessity for monitoring and regular replacement adds to an elevated cost of ownership for such *** utilization of an active output power filter can be used to diminish the dimensions of the LC filter and the electrolytic dc-link capacitor,even though the inclusion of capacitors remains an indispensable part of the *** paper introduces capacitorless solid-state power filter(SSPF)for single-phase dc-ac *** proposed configuration is capable of generating a sinusoidal ac voltage without relying on *** proposed filter,composed of a planar transformer and an H-bridge converter operating at high frequency,injects voltage harmonics to attain a sinusoidal output *** design parameters of the planar transformer are incorporated,and the impact of magnetizing and leakage inductances on the operation of the SSPF is *** analysis,supported by simulation and experimental results,are provided for a design example for a single-phase *** total harmonic distortion observed in the output voltage is well below the IEEE 519 *** system operation is experimentally tested under both steady-state and dynamic conditions.A comparison with existing technology is presented,demonstrating that the proposed topology reduces the passive components used for filtering.

关键词： Solid-state power filter(SSPF) Capacitorless topology Active output power filter(AOF) Planar transformer Electrolytic capacitor Lifetime Wear-out mechanisms

Pharmacological therapy used in the elimination of Helicobacter pylori infection:A review

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2015年第1期21卷 139-154页

作者： Ariolana A dos santos Adriana A Carvalho Department of Pharmacy Federal University of SergipeCampus Lagarto49400-00 LagartoSergipeBrazil

The optimal therapy for Helicobacter pylori(***) infection should combine a high cure rate and a short treatment duration with a favorable side-effect profile and should maintain a low *** strategies have been proposed to increase the *** eradication rate,including the extension of the treatment duration to 14 d,the use of a four-drug regimen(quadruple,sequential,and concomitant treatments),and the use of novel antibiotics,such as ***,triple therapy remains the most widely accepted firstline treatment regimen in Brazil and the United Statesand throughout *** this therapy is limited by resistance to clarithromycin,other therapeutic regimens have been investigated *** review describes the current literature involving studies directly comparing these different therapies and their efficacies.

关键词： Clarithromycin resistant Helicobacter pylori Pepti

Influence of a non-rotating shoulder on heat generation,microstructure and mechanical properties of dissimilar AA2024/AA7050 FSW joints

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2018年第1期34卷 119-127页

作者： Alessandro Barbini Jan Carstensen Jorge F.dos santos Helmholtz-Zentrum Geesthacht Institute of Materials Research Materials Mechanics Solid-State Joining Processes (WMP)

Friction stir welding （FSW） and stationary shoulder friction stir welding （SSFSW） were carried out for the butt joining of dissimilar AA2024-T3 and AA7050-T7651 aluminium alloys with thicknesses of 2 mm. A comparison between the two processes was performed by varying the welding speed while keeping the rotational speed constant, Through the analysis of the force and torque produced during welding and a simple analytical model, it was possible to show that in SSFSW there is more effective coupling with the tool and the heat produced is more efficiently distributed. This process decreases both the welding area and the diffusion at the interface of the two alloys compared with FSW. The minimum microhardness occurred at the advancing side （AS） at the interface between the thermo-mechanically affected zone （TMAZ） and the stir zone （SZ） in both processes, although the decrease was more gradual in SSFSW. This interface is also where all specimens failed for both welding technologies. An increase in tensile strength was measured in SSFSW compared with standard FSW. Furthermore, it was possible to establish the mechanical performance of the material in the fracture zone using digital image correlation.

关键词： Stationary shoulder friction stir welding Friction stir welding Dissimilar welded joints Process analysis Microstructure analysis Mechanical behaviour

Best practices for electrochemical characterization of supercapacitors

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2023年第5期80卷 265-283,I0007页

作者： João Pedro aguiar dos santos Fernando Cesar Rufino Joǎo IYutaka Ota Rodolfo CFernandes Rafael Vicentini Cesar JBPagan Leonardo Morais Da Silva Hudson Zanin Brazilian Renewable Energies Center for Innovation on New EnergiesSchool of Electrical and Computer EngineeringUniversity of CampinasSP 13083-852Brazil School of Electrical and Computer Engineering University of CampinasSP 13083-852Brazil Department of Chemistry Laboratory of Fundamental and Applied ElectrochemistryFederal University of Jequitinhonha e Mucuri's ValleyRodovia MGT 367km 5835000Alto da Jacuba39100-000 DiamantinaMGBrazil

We discuss here essential aspects of the experimental supercapacitors characterization by a series of well-known electrochemical *** are motivated by a considerable number of publications that misreport procedures and *** often conceal or neglect essential information about the electrochemical analytical apparatus used and its *** lack of such information may lead researchers,especially inexperienced ones,to misunderstand the procedures and ***,the misled electrochemical equipment configuration favors misinterpretation of data and low reproducibility *** paper aims to highlight these issues and clarify *** explain fundamental concepts of some electrochemical analytical methods,such as cyclic voltammetry,galvanostatic charge-discharge,single potential step chronoamperometry,and electrochemical impedance spectroscopy,focusing on the supercapacitor *** configurations of electrical parameters are presented and discussed to highlight the effects of incorrect setup and uncover misleading *** discuss how the electrochemical setup and data analyses matter in reliable data results for the supercapacitor.

关键词： Supercapacitor Electrochemical instrumentation Electrochemical methods Electrochemistry

Ion dynamics into different pore size distributions in supercapacitors under compression

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2023年第5期80卷 110-119,I0004页

作者： João Pedro aguiar dos santos Cesar J.B.Pagan Rafael Vicentini Reinaldo F.Teófilo Renato Beraldo Leonardo M.Da Silva Hudson Zanin Brazilian Renewable Energies Center for Innovation on New EnergiesSchool of Electrical and Computer EngineeringUniversity of CampinasAv.Albert Einstein 40CampinasSP13083-852Brazil School of Electrical and Computer Engineering University of CampinasSP 13083-852Brazil Multivariate Chemical Data Analysis Laboratory Department of ChemistryUniversidade Federal de Viçosa36570-900 ViçosaMGBrazil Department of Chemistry Laboratory of Fundamental and Applied ElectrochemistryFederal University of Jequitinhonha and Mucuri's ValleyRodovia MGT 367km 5835000 Alto da Jacuba39100-000DiamantinaMGBrazil

Compressing supercapacitor(SCs)electrode is essential for improving the energy storage characteristics and minimizing ions’distance travel,faradaic reactions,and overall ohmic *** comprising the ion dynamics in SC electrodes under compression are still ***,the ionic dynamics of five aqueous electrolytes in electrodes under compression were studied in this work for tracking electrochemical and structural changes under mechanical stress.A superionic state is formed when the electrode is compressed until the micropores match the dimensions with the electrolyte’s hydrated ion sizes,which increases the *** excessive compression is applied,the accessible pore regions decrease,and the capacitance ***,as the studied hydrated ions have different dimensions,the match between ion/pore sizes *** the LiOH and NaClO4electrolytes,increasing the pressure from 60 to 120 and 100 PSI raised the capacitance from 13.5 to 35.2 F g^(-1)and 30.9 to 39.0 F g^(-1),***,the KOH electrolyte with the lowest and LiCl with the biggest combination of hydrated ion size have their point of maximum capacitance(39.5 and 36.7F g^(-1))achieved at 140 and 80 PSI,*** LiCl and KCl electrolytes,overcompression causes a drop in capacitance higher than 23%.

关键词： Mechanic compression Pore size distribution lon dynamics Activated carbon Supercapacitors

Microencapsulated oregano and cinnamon essential oils as a natural alternative to reduce Listeria monocytogenes in Italian salami

在线全文

学校读者我要写书评

暂无评论

Food Bioscience 2022年第6期50卷 1766-1773页

作者： Franciele Maria Gottardo Bárbara Biduski Lára Franco dos santos Jucilene Sena dos santos Laura Beatriz Rodrigues Luciana Ruschel dos santos Graduate Program in Food Science and Technology University of Passo FundoBR 28599052-900Passo FundoRSBrazil Food Quality and Sensory Science Department Teagasc Food Research CentreAshtownDublinD15 KN3KIreland Graduate Program in Bioexperimentation University of Passo FundoBR 28599052-900Passo FundoRSBrazil College of Agronomy and Veterinary Science University of Passo FundoBR 28599052-900Passo FundoRSBrazil

Meat products are classified as perishable foods and have favourable conditions for the multiplication of microorganisms such as Listeria monocytogenes,an important pathogen associated with ready-to-eat *** compounds are used for food preservation combined with encapsulation techniques to improve *** study evaluated the anti-Listeria potential of isolated and combined microencapsulated oregano(OEO)and cinnamon(CEO)essential oils in Italian *** combination ratios of OEO and CEO were tested and 50:50 ratio(OEO:CEO)was encapsulated using sodium *** microcapsules were evaluated for encapsulation efficiency(EE),morphology and action against *** in a meat *** microcapsules and 50/50 combined EO were incorporated into the Italian salami to evaluate the physicochemical,microbiological and sensory *** combinations of EO showed *** inhibition zone and CIM with 1:16 *** microencapsulated EO had 98.36%encapsulation *** 2%microcapsule had a significant reduction of *** from the *** though the panellists mentioned the sandy attribute in the CATA,the salami with EO microcapsules texture did not differ from the *** the essential oils had high encapsulation efficiency,the smell and flavour of cinnamon and oregano interfered negatively with the sensory ***,the encapsulation of the combined essential oils(50/50)significantly reduced *** in Italian salami.

关键词： Natural antimicrobial Sodium alginate Ready-to-eat Encapsulation

Building capabilities in natural resource-dependent economies:An innovation systems analysis of the TVET program in Guyana

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Innovation Studies 2019年第1期3卷 1-11页

作者： Chantal dos santos Friedrich-Alexander University Erlangen-Nuremberg 91054 ErlangenGermany

This paper examines Guyana's technical and vocational education and training(TVET)system in relation to diversifying the country's economy away from natural resource *** innovation systems approach is used to examine the effectiveness of TVET as a means of building capabilities in Guyana's key industries,gold and sugar,providing a snapshot of the state of the system in early,*** interviewees across several areas of expertise were consulted in Georgetown,*** analysis of primary and secondary research finds TVET's effectiveness to be limited by a lack of labor market information and funding,energy costs,a“brain drain”,and insufficient information communication technology skills and *** remedies include increasing the frequency of labor market surveys,attracting the Guyanese diaspora back to share knowledge,reducing the cost of energy by taking advantage of domestic renewable energy potential,and setting up a Sovereign Wealth Fund.

关键词： Innovation systems Guyana CARICOM Natural resources TVET