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Malaria prevalence in north-eastern Nigeria:A cross-sectional study Houben ch^(1*),Fleischmann H^2,Gǜckel M^3

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Asian Pacific Journal of Tropical Medicine 2013年第11期6卷 865-868页

作者： Houben ch Fleischmann H Gckel M Diagnostic Center MMM group & Specialist Hospital Yola Hospital RoadP.M.B.2266YolaAdamawa.StateNigeria Medical Mission Institute Tropical MedicineHermann Schell Str 797074 WrzburgGermany Helios Kliniken Schwerin Wismarsche Str 393-39719049 SchwerinGermany

Objective:To assess the prevalence of malaria parasitemia in north-east Nigeria and to evaluate the measures for the prevention of ***:A village in north-eastern Nigeria was selected for the cross sectional study at the height of the rainy season in October 2011.A total of 550 inhabitants of a hamlet were recruited for this *** obtaining the consent individuals received a structured interview and were tested for malaria parasites in their blood *** testing positive for malaria were given a course of artemesinin-based combination therapy（ACT）.Results:A total of 497 inhabitants representing approximately 90 percent of the population participated:a quarter of the study group carried malaria parasitesexclusively Plasmodium falciparum（***）-representing a *** parasite rate（PfPR） of 24.5%.Besides,53/138 in the age group of 2 to children tested positive for *** representing a PfPR2-10 value of 38.4%.Malaria control measures were used in just under a third（157/497） of this *** these measures 28/157（17.8%） still tested positive for ***:The malaria burden is overestimated for this region in north-east *** findings support an intermediate pattern of malaria *** 30%bed nets coverage for malaria control is well below the WHO estimates for 2011.

关键词： Malaria control Malaria endemicity Malaria prevalence Malaria transmission

Electronic factor in electron self-exchange reaction of hydrated redox ion pairs from thermodynamic data

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chinese Journal of chemistry 1997年第3期15卷 201-210页

作者： Bu, YX Deng, ch SHANDONG UNIV INST THEORET CHEMSHANDONG 250100PEOPLES R CHINA

An accurate scheme for determining the electronic factor of the electron self-exchange reaction in solution is presented in this paper. The used various activation parameters and slopes of potential energy surfaces are obtained in terms of an improved activation model and the accurate potential function determined from the vibrational spectroscopic and thermodynamic data. The coupling matrix elements are determined using numerical integral method over the perturbed double-zeta Slater type state functions. Theoretical results of electronic factor in this work are found in close agreement with those extracted from experimental rate constant data and to be less than unity. Results indicate that outer-sphere electron transfer reactions in solution involving hydrated transition metal ions are nonadiabatic in nature.

关键词： electronic factor Landau-Zener probability activation model hydrated transition metal ions

Polygeneration Study of Low-to-Medium Enthalpy Geothermal Reservoirs in Mexico

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Journal of Thermal Science 2021年第3期30卷 1077-1087页

作者： chÁVEZ Oscar GODÍNEZ Francisco Tecnológico Nacional de México/I.T.chihuahua.Av.Tecnológico 2909 C.P.31310ChihuahuaChihuahuaMéxico Instituto de Ingeniería Universidad Nacional Autónoma de MéxicoUNAMC.U.Ciudad de MéxicoC.P.04510México Polo Universitario de Tecnología Avanzada Universidad Nacional Autónoma de MéxicoVía de la Innovación No.410Autopista Monterrey-Aeropuertokm.10 PIITC.P.66629Apodaca Nuevo LeónMéxico

This study combines the thermodynamic analysis of a polygeneration system along with the numerical modelling of the thermal behavior of geothermal reservoirs in Mexico to exploit their *** reservoir was modeled as a porous medium assuming a five-spot well configuration and local thermal *** heat conduction-convection along with the Laplace equations were solved to compute temperature distributions,the useful life and the optimum distance between injection-extraction *** predicted temperature and pressure of the geothermal fluid at the outlet of the reservoir were exploited in the polygeneration system consisting of:(1)a Rankine cycle,(2)an absorption refrigeration cycle,and(3)a heat *** developed approach allows calculating both the optimal distance between injection-extraction wells and the global(utilization)efficiency of six arrangements(each composed by a reservoir connected to a polygeneration system)by assuming that reservoirs have a lifespan of 30 *** also show that:(a)due to the low efficiency of the Rankine cycle,very little thermal energy is converted into electrical one;(b)not only the temperature and the size are important when evaluating the power production performance of reservoirs,but also the permeability plays a fundamental role;(c)the first law efficiency of the polygeneration system ranges from 41.9%to 43.7%;(d)the utilization efficiency of the six arrangements lies in the range between 25.8%and 31%.

关键词： polygeneration system geothermal reservoir local thermal equilibrium low-to-medium enthalpy

Photochemical reaction of azobenzene in solvent-swollen Nafion membranes

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chinese Journal of chemistry 1996年第6期14卷 541-548页

作者： Tung, ch Guan, JQ chINESE ACAD SCI INST PHOTOG CHEMBEIJING 100101PEOPLES R CHINA

The photochemical reactions of azobenzene (AB) incorporated into different solvent-swollen Nafion membranes were investigated. The location of azobenzene in water-swollen Nafion membranes was different from that in methanol-swollen Nafion membranes, which was responsible for the different photochemical reactions of AB. In methanol-swollen Nafion membranes only transcis isomerization took place, while in water-swollen Nafion membranes photochemical cyclization of AB occurred after rapid transcis isomerization. The relation between the relative quantum yields and the light intensity showed that the cyclization was a two-photo process. The numbers of AB molecules per cluster (n(AB)/cluster) in Nafion membranes with different AB concentrations and different water contents were calculated. Under the experimental condition two competitive photocyclization mechanisms were suggested by n(AB)/cluster in Nafion membranes, relative quantum yields of the cyclization, and the change of the ratio of benzidine to benzo[c]cinnoline.

关键词： Nafion photochemical reaction azobenzene

Contrasting plant growth performance of invasive polyploid and native diploid Prosopis is mediated by the soil bacterial community

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Ecological Processes 2023年第1期12卷 193-203页

作者： Rishabh Kaushik Meesha Sharma ch.V.Ramana ch.Sasikala Maharaj K.Pandit Jealott’s Hill International Research Centre WarfieldBracknell RG426EYEnglandUK Department of Environmental Studies University of DelhiDelhi 110007India Department of Plant Sciences School of Life SciencesUniversity of HyderabadP.O.Central UniversityHyderabad 500046India Bacterial Discovery Laboratory Centre for EnvironmentInstitute of Science and TechnologyJ.N.T.University HyderabadKukatpallyHyderabad 500085India Jindal School of Environment&Sustainability OP Jindal Global UniversitySonipatHaryana 131001India

Background Soil microbial communities affect above-ground plant diversity and community composition by influencing plant growth *** studies have tested the effect of soil bacterial microbiome on growth performance of native and invasive plants,but the influence of specific bacterial isolates has not been ***,we investigated the effects of soil bacterial exclusion by soil sterilization and by inoculation of Streptomyces rhizobacterial isolates on the growth performance of native and invasive Prosopis *** Plant growth performance of invasive *** was significantly reduced when grown in sterilized soils,whereas native *** showed enhanced growth performance in the sterilized *** grown in the soil inoculated with the specific Streptomyces isolate from ***(PJ1),the growth performance of invasive *** was significantly enhanced while that of native *** seedlings was significantly ***,inoculation of *** and *** seedlings with Streptomyces isolate from the rhizosphere of native ***(PC1)had no significant effect on the growth performances either of *** or *** Our study reveals that invasive *** experiences positive feedback from the non-native soil bacterial community,while the native *** experiences negative feedback from its soil bacterial *** results provide fresh experimental evidence for the enemy release hypothesis,and further our understanding of the contrasting growth-promoting effects of differentially recruited microbial species belonging to the same genus(Streptomyces)in the rhizospheres of alien invasive and native plants.

关键词： Soil bacteria Streptomyces Invasive Prosopis juliflora Prosopis cineraria Soil microbiota

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Stochastic many-body calculations of moiréstates in twisted bilayer graphene at high pressures

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npj Computational Materials 2022年第1期8卷 89-98页

作者： Mariya Romanova Vojtěch Vlček Department of chemistry and Biochemistry University of CaliforniaSanta BarbaraCA93106-9510USA

We introduce three developments within the stochastic many-body perturbation theory:efficient evaluation of off-diagonal self-energy terms,construction of Dyson orbitals,and stochastic constrained random phase *** stochastic approaches readily handle systems with thousands of *** use them to explore the electronic states of twisted bilayer graphene(tBLG)characterized by giant unit cells and correlated electronic *** document the formation of electron localization under compression;weakly correlated states are merely shifted in *** demonstrate how to efficiently downfold the correlated subspace on a model Hamiltonian with a screened frequency-dependent two-body *** the 6°tBLG system,the onsite interactions are between 200 and 300 meV under *** Dyson orbitals exhibit spatial distribution similar to the mean-field single-particle *** pressure,the electron-electron interactions increase in the localized states;however,the dynamical screening does not fully balance the dominant bare Coulomb interaction.

关键词： interaction twisted stochastic

Phase Evolution during the Sintering of Submicron Ti(C,N)-Based Cermets

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Rare Metals 2001年第4期20卷 248-254页

作者： Li, ch Xiong, WH Yu, LX Huazhong Univ Sci & Technol State Key Lab Plast Forming Simulat & Die & Mould Wuhan 430074 Peoples R China

The submicron powder mixtures of TiC-TiN-WC-Mo-C-Ni sintered at 1400degreesC or below in vacuum were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analyses. The results showed that Mo2C formed at 800degreesC or below. Both WC and Mo2C disappeared at 1200degreesC, and TiN disappeared at 1250degreesC. In addition, the variations of lattice constants of the titanium carbonitride and nickel binder phase with sintering temperature were experimentally obtained, and the reason was analyzed.

关键词： submicron cermet phase sintering

Peraluminous A-type granites formed through synchronous fractionation,magma mixing,mingling,and undercooling:evidence from microgranular enclaves and host Mesoproterozoic Kanigiri granite pluton,Nellore Schist Belt,southeast India

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Acta Geochimica 2023年第4期42卷 603-636页

作者： ch.Narshimha Santosh Kumar Department of Geology Centre of Advanced StudyKumaun UniversityNainital 263001India

The field and microstructural features coupled with mineral chemical data from microgranular enclave(ME)and host Mesoproterozoic Kanigiri granite(KG)pluton of Nellore Schist Belt(NSB),Southeastern India,have been documented in order to infer the likely processes responsible for the origin and evolution of ME and host KG *** ME and host KG bear the same mineral assemblages barring the KG which does not contain amphibole;however,they are modally *** ME in KG is originated due to multiple intrusions of ME magmas into the crystallizing host KG magma *** and textural features indicate the dynamic magma flow,mingling,and undercooling of the ME against a relatively cooler surface of host KG *** presence of NSB country rock xenoliths and its diffuse boundaries suggest the intrusive relation and marginal assimilation by the intruding KG *** occasional cumulate texture in the ME appears to have formed by the accumulation of early-formed minerals that crystallized rapidly in the ME magma *** ME shows the magmatically deform features developed due to the flowage and erosion by the subsequent intrusions of ME magma pulses into the crystallizing host KG magma *** ME amphiboles show unusual composition as ferro-edenitic hornblende to potassian-hastingsitic hornblende,that crystallized in the subalkaline-alkaline transition,low fO_(2)(reducing to mildly oxidizing)*** unusual extremely low Mg/Mg+Fe^(t)=0.015(avg.)of ME amphiboles may be related to the changing physico-chemical(P,T,fO_(2),and H_(2)O)condition of the ME magma or they might have crystallized in equilibrium with more evolved KG *** KG(FeOt/MgO=37.04,avg.)and ME(FeO~t/MgO=77.72,avg.)biotites are siderophyllite,and buffered between QFM and NNO syn-crystallizing in the water undersaturated(H_(2O)≈3.58 wt.%in KG;≈3.53wt.%in ME),alkaline anorogenic(A-type)host magmas that were emplaced at mid-crustal(4–5 kbar;17 km)***,microtextural and mineral

关键词： Enclave Kanigiri granite Magma mixing-fractionation Nellore schist belt SE India

Photophysical Behaviors of Azobenzene in Solvent-Swollen Nafion Membranes

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chinese chemical Letters 1996年第10期7卷 944-947页

作者： Guan, JQ Tung, ch ACAD SINICA INST PHOTOG CHEMBEIJING 100101PEOPLES R CHINA

The fluorescence from azobenzene (AB) molecule incorporated into water-swollen Nafion in acid form was observed at room temperature for the first time. The incorporation process was investigated by UV absorption. The plot of the concentration of AB in Nafion vs. the soaking time shows that the adsorption process is diffusion-controlled, and the apparent diffusion coefficient (D) was determined to be 7.6x10(-10) cm(2)s(-1). These results are attributed to the fact that AB molecules are located in the fluorocarbon/water interface of the Nafion membranes and are protonated. In methanol-swollen Nafion membranes, AB fails to fluoresce because it is located at the methanol pool enclosed by the cluster networks.

关键词： Photophysical Behaviors of Azobenzene in Solvent-Swollen Nafion Membranes