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Climate Smart Agriculture: Achievements and Prospects in Africa

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Journal of Geoscience and Environment Protection 2015年第6期3卷 99-105页

作者： Adornis D. Nciizah isaiah i. C. Wakindiki Agricultural Research Council—institute for Soil Climate and Water Pretoria South Africa

Smallholder agriculture is facing a myriad of challenges in the wake of a changing climate. To counter this, several measures have been suggested in attempts to reduce the vulnerability of smallholder farmers who are the worst affected by changes in climate. However, despite these interventions not much improvement in agricultural production has been realized by the smallholder farmers. This suggests the need for more alternative options for these resource poor farmers. One such intervention is climate smart agriculture (CSA), which is probably one of the most viable and sustainable options. it offers both mitigation and adaptation measures to climate changes. However, problems of its viability and sustainability have been raised by several authors who argue that there are barriers, limits and costs, which may hinder its adoption by farmers. This review discusses the achievements attained so far in improving the productivity of smallholder agricultural soils under changing climatic conditions. The review also looks at the prospect of CSA with regards to South African smallholder agriculture.

关键词： Adaptation Mitigation Recovery Soil Health Soil Management

Beneficial effect of reduced oxygen concentration with transfer of blastocysts in iVF patients older than 40 years old

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Health 2010年第9期2卷 1010-1017页

作者： Javier i. García Soledad Sepúlveda Luis Noriega-Hoces 不详

The aim of the present study was to determine the impact of oxygen concentration on implantation, pregnancy and delivery rates in iVF patients older than 40 year old with transfer of blastocysts. included were 558 women aged 23-45 years old undergoing iVF/iCSi procedures whose embryos were cultured at blastocyst stage under two different oxygen environments (a bi-gas system: 5.6% CO2 in air and a tri-gas system: 5.6% CO2, 5% de O2 and 89.4% N2). The main outcome measures of this study are implantation, pregnancy and delivery rates. implantation, pregnancy and delivery rates are found to be reduced in women older than 40 years old. The implantation and pregnancy rates are significantly higher in women older than 40 years old from the 5% of O2 group, in comparison to the 20% group (25.00% versus 2.70% and 41.38% versus 5.56%;P iveries rates were 13.79% and 5.56% in the 5% and 20% oxygen groups respectively (P: NS). The birthweight was similar in both study groups (P: NS). Gestational age was significantly longer in wo- men from the 5% of O2 group, in comparison to the 20% (36.87 versus 35.87 weeks, P indicated that the embryonic culture with 5% of oxygen and transfer of blastocysts in women older than 40 years old improve the results in the in Vitro fertilization/intracytoplasmic injection procedures (iVF/iCSi).

关键词： ART Blastocyst iVF iCSi Oxygen

The association of Triatoma maculata(Ericsson 1848) with the gecko Thecadactylus rapicauda(Houttuyn 1782)(Reptilia:Squamata:Gekkonidae):a strategy of domiciliation of the Chagas disease peridomestic vector in Venezuela?

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Asian Pacific Journal of Tropical Biomedicine 2011年第4期1卷 279-284页

作者： Reyes-Lugo M Reyes-Contreras M Salvi i Gelves W Avilan A Llavaneras D Navarrete LF Cordero G Sanchez EE Rodriguez-Acosta A Medical Entomology Section Institute of Tropical MedicineUniversidad Central de VenezuelaCaracasVenezuela School of Biology Universidad Simon BolivarCaracasVenezuela immunochemistry Section Tropical Medicine InstituteUniversidad Central de VenezuelaCaracasVenezuela Tropical Zoology institute Universidad Central de VenezuelaCaracasVenezuela Texas A&M University-Kingsville Department of ChemistryKingsvilleTexasUSA instituto Nacional de Higiene Rafael Rangel CaracasVenezuela

Objective:To investigate the bioecological relationship between Chagas disease peridomestic vectors and reptiles as source of ***:in a three-story building,triatomines were captured by direct search and electric vacuum cleaner search in and outside the ***,age structure of the captured Triatoma maculata(***) were identified and *** living in sympatric with the triatomines were also ***:*** were found living sympatric with geckos(Thecadactylus rapicauda) and they bit residents of the apartment building in study.A total of 1 448 individuals of *** were captured within three days,of which 74.2%(1 074 eggs) were eggs,21.5%were nymphs at different stages,and 4.3%were ***:The association of *** and *** is an effective strategy of colonizing dwellings located in the vicinity of the habitat where both species are present;and therefore,could have implications of high importance in the intradomiciliary transmission of Chagas disease.

关键词： Chagas disease Gekkonidae Reduviidae Thecadactylus rapicauda Triatoma maculate Trypanosoma cruzi Vector domiciliation

Presence of Multifractality in High-Energy Nuclear Collisions

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Journal of Modern Physics 2014年第17期5卷 1889-1895页

作者： M. i. Haque M. Tariq Tahir Hussain Department of Kulliyat AK Tibbiya College Aligarh Muslim University Aligarh India Department of Physics Aligarh Muslim University Aligarh India Department of Applied Physics Aligarh Muslim University Aligarh India

in the present study an attempt is made to examine multifractality in multiparticle production in relativistic nuclear collisions;multifractality is investigated in 14.5 A GeV/c 28Si-nucleus collisions. For this, Gq-moments are calculated and variations of ?are looked into. Values of mass exponents, tq, and generalised dimensions, Dq, are obtained. Analysis of multifractal moments reveals that multiplicity fluctuations are of dynamical nature.

关键词： Multifractal Moments Dynamical Fluctuations Quark-Gluon Plasma Emulsion

Unveiling bulk and surface radiation forces in a dielectric liquid

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Light(Science & Applications) 2022年第5期11卷 925-934页

作者： N.G.C.Astrath G.A.S.Flizikowski B.Anghinoni L.C.Malacarne M.L.Baesso T.Požar M.Partanen i.Brevik D.Razansky S.E.Bialkowski Department of Physics Universidade Estadual de MaringáMaringáPRBrazil Faculty of Mechanical Engineering University of LjubljanaLjubljanaSlovenia Department of Electronics and Nanoengineering Aalto UniversityAaltoFinland Department of Energy and Process Engineering Norwegian University of Science and TechnologyTrondheimNorway institute for Biomedical Engineering and institute of Pharmacology and Toxicology Faculty of MedicineUniversity of ZurichZurichSwitzerland institute for Biomedical Engineering Department of Information Technology and Electrical EngineeringETH ZurichZurichSwitzerland Department of Chemistry and Biochemistry Utah State UniversityLoganUTUSA

Precise control over light-matter interactions is critical for many optical manipulation and material characterization methodologies,further playing a paramount role in a host of nanotechnology ***,the fundamental aspects of interactions between electromagnetic fields and matter have yet to be established unequivocally in terms of an electromagnetic momentum ***,we use tightly focused pulsed laser beams to detect bulk and boundary optical forces in a dielectric *** the optical convoluted signal,we decouple thermal and nonlinear optical effects from the radiation forces using a theoretical interpretation based on the Microscopic Ampère force *** is shown,for the first time,that the time-dependent pressure distribution within the fluid chiefly originates from the electrostriction *** results shed light on the contribution of optical forces to the surface displacements observed at the dielectric air-water interfaces,thus shedding light on the long-standing controversy surrounding the basic definition of electromagnetic momentum density in matter.

关键词： dielectric momentum surface

Application of a new reagent for analysis of oxygen presence in a lowcarbon steel wire rod

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Journal of iron and Steel Research international 2021年第6期28卷 729-738页

作者： M.i.Dávila-Pérez H.J.Vergara-Hernández O.Vázquez-Gómez F.Reyes-Calderón E.López-Martínez J.M.Salgado-López National Technology of Mexico/T.i.of Morelia Morelia 58120MichoacanMexico National Council for Science and Technology CONACYT Mexico City 03940Mexico isthmus University Santo Domingo TehuantepecOaxaca 70760Mexico Engineering and industrial Development Center CiDESi Santiago de Queretaro 76125QueretaroMexico

A microstructural analysis was performed to determine the presence of oxygen in a wire rod section of AiSi 1008 steel with a surface mechanical failure produced during wire *** failure zone was analyzed by comparison using three different attack reagents:alkaline sodium chromate(ASC),ASC with hydrogen peroxide and amyl alcohol,and a solution of nitric acid in ethyl *** reagents were applied in samples in the failure zone,showing different types of zones in regions with internal and superficial defects such as carbides,pores,cracks,deformation,and detachment zones,indicating the possible presence of *** areas identified were observed by means of an optical microscope and were correlated with the content of elements that were present in the region using a scanning electron microscope and a scattered X-ray energy spectrometer,which determined that the areas identified by chromate sodium correspond to regions with a high concentration of oxygen and slag-forming elements such as silicon,aluminum,and iron;this is associated with the presence of oxygen in the oxide *** was also observed that the ASC and the modified ASC solution with hydrogen peroxide and amyl alcohol could identify areas with a high presence of oxides,while the nitric acid solution only identified the steel *** modified ASC solution is an alternative to identify the presence of chemical variants of oxygen because the conventional formulation is unstable and has a too short shelf life,and therefore,its application must be carried out at the time of preparation.

关键词： Etching Alkaline sodium chromate Oxide presence internal defect

Luminescent Composite Films Based on Mechanically Strong Ladder-like Polyphenylsilsesquioxane and Oligophenyleuropiumsiloxane

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Chinese Journal of Polymer Science 2024年第11期42卷 1793-1801,I0013页

作者： E.E.Kim T.O.Ershova A.S.Belova D.A.Khanin E.V.Bashkova G.G.Nikiforova Yu.N.Kononevich A.A.Anisimov O.i.Shchegolikhina A.M.Muzafarov A.N.Nesmeyanov institute of Organoelement Compounds Russian Academy of SciencesMoscow119334Russian Federation Tula State Lev Tolstoy Pedagogical University Tula300026Russian Federation V.Topchiev institute of Petrochemical Synthesis Russian Academy of Sciences Moscow119991Russian Federation Moscow institute of Physics and Technology(National Research University) DolgoprudnyMoscow Region141700Russian Federation N.S.Enikolopov institute of Synthetic Polymeric Materials Russian Academy of SciencesMoscow117393Russian Federation

Nowadays organosilicon luminescent materials are of increasing interest due to the variety of their synthetic or modification techniques and application *** polyphenylsilsesquioxanes(L-PPSQ)are a unique class of organosilicon polymers,which can be ideal matrices for the luminescent composites due to their high thermal stability,optical transparency and mechanical *** this work,new mechanically strong,heat-resistant,transparent and sensitive to ammonia vapor luminescent composite films based on L-PPSQ have been *** the source of Europium ions oligophenyleuropiumsiloxane was used,demonstrating perfect compatibility to the matrix due to the similar *** improve luminescent properties of the films,new organosilicon ligands were introduced into the composites and their influence on the properties of the materials was *** properties of described composites may allow their further application as multifunctional coatings.

关键词： Luminescent composite films Ladder-like polyphenylsilsesquioxane Oligophenyleuropiumsiloxane

Seasonal variation and chemical composition of particulate matter： A study by XPS, iCP-AES and sequential microanalysis using Raman with SEM/EDS

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Journal of Environmental Sciences 2018年第12期30卷 32-49页

作者： Lucy T.González Francisco E.Longoria-Rodríguez Margarita Sánchez-Domínguez Cesar Leyva-Porras Karim Acuna-Askar Boris i.Kharissov Alejandro Arizpe-Zapata Juan M.Alfaro-Barbosa Universidad Autónoma de Nuevo León Facultad de Ciencias Químicas Laboratorio de Química Analítica AmbientalCódigo Postal 64570MaonterreyN.L.Mexico Centro de investigación en Materiales Avanzados SC Unidad MonterreyAlianza Notre 202 Código Postal 66628 Apodaca Nueuo León Mexico Centro de investigación en Materiales Avanzados SC Miguel de Cervantes # 120 Código Postal 31109 Chihuahua Chih. Mexico Universidad Autónoma de Nuevo León Facultad de Medicina Laboratorio de Biorremediación AmbientalCódigo Postal 64460 MonterreyN.L. Mexico

During the winter period（January–March 2016）, the total suspended particles（TSP） and particulate matter smaller than 2.5 μm（PM2.5） were characterized by the application of various analytical techniques in four zones of the Metropolitan Area of Monterrey in Mexico. To evaluate the seasonal variation of some elements in the particulate matter, the results of this study were compared with those obtained during the summer season（July–September 2015）. The speciation of the C_（1s） signal by X-ray photoelectron spectroscopy revealed the contribution of aromatic and aliphatic hydrocarbons as the main components in both seasons. Conversely, carboxylic groups associated with biogenic emissions were detected only in winter. The percentages of SO_4^（2-） ions were lower in winter, possibly caused by the decrease in the solar radiation, and relative humidity recorded. The results of the iCP analysis revealed that Fe, Zn and Cu were the most abundant metals in both TSP and PM2.5 in the two seasons. There were significant seasonal variations for concentrations of As, Ni and Zn in the urban area and for Fe, As, Cd, Ni and Zn in the industrial zone. This was attributed to the greater burning of fuels as well as to an increase in vehicular traffic, the effect of thermal inversion and changes in some meteorological parameters. The results of the sequential microanalysis by Raman spectroscopy and SEM/EDS allowed observation of deposits of carbonaceous material on the particles and to perform the speciation of particles rich in Fe and Pb, which helped infer their possible emission sources.

关键词： Seasonal variation Total suspended particles PM2.5 X-ray photoelectron spectroscopy Micro-Raman spectroscopy

Characterization and Electrochemical Properties of Nanostructured Zr-Doped Anatase TiO_2 Tubes Synthesized by Sol–Gel Template Route

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Journal of Materials Science & Technology 2017年第6期33卷 527-534页

作者： Denis P.Opra Sergey V.Gnedenkov Sergey L.Sinebryukhov Elena i.Voit Alexander A.Sokolov Evgeny B.Modin Anatoly B.Podgorbunsky Yury V.Sushkov Veniamin V.Zheleznov institute of Chemistry Far Eastern Branch of Russian Academy of Sciences Far Eastern Federal University National Research Centre "Kurchatov institute"

A series of nanostructured Zr-doped anatase TiO_2 tubes with the Zr/Ti molar ratio of 0.01, 0.02, 0.03, and0.09 were prepared by a sol–gel technology on a carbon fiber template. The electrochemical performance of Zr-doped anatase TiO_2 as anodes for rechargeable lithium batteries was investigated and compared with undoped titania. Tests represented that after 35-fold charge/discharge cycling at C/10 the reversible capacity of Zr-doped titania（Zr/Ti = 0.03） reaches 135 m A h g^（-1）, while the capacity of undoped titania（Zr/Ti = 0） yielded only 50 m A h g^（-1）. Based on the results of the physicochemical investigation, three reasons of improving electrochemical performance of Zr-doped titania were suggested. According to the scanning electron microscopy and transmission electron microscopy, Zr^（4＋） doping induces a decrease in nanoparticle size, which facilitates the Li＋diffusion. The Raman investigations show the more open structure of Zr-doped TiO_2 as compared to undoped titania due to changing of the unit cell parameters, that significantly affects on the reversibility of the insertion/extraction process. The electrochemical impedance spectroscopy results indicate that substitution of Zr^（4＋） for Ti^（4＋） into anatase TiO_2 has favorable effects on the conductivity.

关键词： Li-ion batteries Anatase titania Nanostructured materials Sol–gel template process Doping Electrochemical performance