检索结果-南通市图书馆

Effect of insulin on Blattela germanica Linnacus

在线全文

学校读者我要写书评

暂无评论

Asian Pacific Journal of Tropical Biomedicine 2011年第4期1卷 285-288页

作者： Abolghasemi E moosa Kazem sh Abolhasani m Davoudi m Department of medical Entomology and Vector Control School of Public HealthTehran University of Medical Sciences

Objective:To determine the sensitivity of Blattela germanica L(*** L) to differenct doses of ***:*** were reared in laboratory conditions at(25±2) ℃ and(50±5)%relative humidity(RH),and exposure period of 12:12 L/*** concentrations,viz.5,10,15,20 and 25 μ of insulin N,R,(N+R) were prepared and injected to 10 treated cockroaches with another 10 cockroaches which were injected with normal saline as control ***:Insulin N with a dose of 20 μ caused more than 70%mortality of *** in this *** was a significant difference between 20 μ of insulin N with other doses of 5,10,15 and 25 μ,and its comparison with other forms of medication also showed obvious difference(Pg doses of insulin which can be used as posion bait or gel against german cockroaches could be utilized in the control of *** in the future field studies.

关键词： Insulin Rearing Blattela germanica Insectary Sensitivity

Natural Convection of a Power-Law Nanofluid in a Square Cavity with a Vertical Fin

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

Fluid Dynamics & materials Processing 2024年第9期20卷 2091-2108页

作者： Amira m’hadbi mohammed El ganaoui Haïkel Ben Hamed Amenallah guizani Khalid chtaibi LERmAB Department of Transition and Energy Efficiency ProfessionsIUT H Poincaréde LongwyUniversity of LorraineLongwy54400France LPT Center for Energy Research and Technologies(Borj Cedria2084)University of Tunis El ManarTunis1068Tunisia LTI Department of Mechanical Engineering and ProductionIUTUniversity of Picardie Jules-VerneAmiens80025France

The behavior of non-Newtonian power-law nanofluids under free convection heat transfer conditions in a cooled square enclosure equipped with a heated fin is investigated *** particular,the impact of nanofluids,composed of water and Al_(2)O_(3),TiO_(2),and Cu nanoparticles,on heat transfer enhancement is *** aim of this research is also to analyze the influence of different parameters,including the Rayleigh number(Ra=10^(4)-10^(6)),nanoparticle volume fraction(φ=0%-20%),non-Newtonian power-law indexes(n=0.6-1.4),and fin dimensions(Ar=0.3,0.5,and 0.7).Streamlines and isotherms are used to depict flow and related heat transfer *** indicate that thermal performance improves with increasing Rayleigh number,regardless of the nanoparticle type or nanofluid rheological *** suggests that the buoyancy force has a significant impact on heat transfer,particularly near the heat *** Nusselt number is more sensitive to variations in Cu nanoparticle volume fractions compared to Al₂O₃and TiO₂.moreover,the average Nusselt numbers for power-law nanofluids with n1)are greater(smaller)than for Newtonian fluids due to the decrease(increase)in viscosity with increasing(decreasing)shear rate,at the same values of Rayleigh number Ra owing to the amplification(attenuation)of the convective ***,the most substantial enhancement is observed with Cu-water shear-thinning nanofluid,where the Nusselt number increases by 136%when changing from Newtonian to shear thinning behavior and by 154.9%when adding 16%nanoparticle volume ***,an even larger increase of 57%in the average Nusselt number is obtained on increasing the fin length from 0.3 to 0.7.

关键词： Heat transfer nanofluid non-Newtonian fluid natural convection

characteristics of ionospheric scintillation climatology over Indian low-latitude region during the 24th solar maximum period

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

geodesy and geodynamics 2019年第2期10卷 110-117页

作者： K.Sahithi m.Sridhar Sarat K.Kotamraju K.ch.Sri Kavya g.Sivavaraprasad D.Venkata Ratnam ch.Deepthi Department of Electronics and Communication Engineering Koneru Lakshamaiah Education Foundation

The amplitude and phase of L-band satellite signals are fluctuated randomly due to small scale electron density irregularity structures in the ionosphere which result in fleeting variations, known as 'ionospheric scintillations'. The global Navigation Satellite System(gNSS) is a profound remote sensing tool to monitor, model and forecast the ionospheric weather conditions. In this paper, the gNSS amplitude scintillation data has been analyzed during the year 2013 at Bengaluru(12.9°N, 77.59°E) and Lucknow(26.8467°N, 80.9462°E) stations to reinforce climatology of ionospheric scintillation over Indian low-latitude region. The probability of scintillation occurrence and their variations over equatorial and Equatorial Ionization Anomaly(EIA) regions in India are analyzed during various geomagnetic quiet and disturbed days, months and seasons. The annual occurrence of amplitude scintillations are mapped with the function of local time. It is observed from the experimental results that the probability of scintillations occurrences is higher over EIA region than over the equatorial region. The probability of scintillations is higher during march equinox and December solstice, and lowest during June *** of scintillations is intense during post-sunset period. The maximum percentage of scintillation occurrences at the two stations are recorded in November. moreover, the highest percentage of scintillation occurrences took place on storm day(march 17, 2013) at the two stations. This work would be helpful for understanding the features of gNSS amplitude scintillations over Southern and Northern Indian regions. moreover, these kinds of investigations are helpful for developing new algorithms to nowcast and forecast ionospheric scintillations over Indian Sub-continent.

关键词： gNSS Ionospheric scintillations Indian low-latitude region

Asynchronous Nested Optimization Algorithms and Their Parallel Implementation

在线全文

学校读者我要写书评

暂无评论

Wuhan University Journal of Natural Sciences 2001年第Z1期6卷 560-567页

作者： Hans W. moritsch, g.ch. Pflug, m. Siomak Department of Statistics and Decision Support Systems,University of Vienna, Universitaetsstrasse 5 A\|1090 Vienna, Austria Department of Statistics and Decision Support Systems University of Vienna Vienna Austria

Large scale optimization problems can only be solved in an efficient way, if their special structure is taken as the basis of algorithm design. In this paper we consider a very broad class of large-scale problems with special structure, namely tree structured problems. We show how the exploitation of the structure leads to efficient decomposition algorithms and how it may be implemented in a parallel environment.

关键词： financial management stochastic optimization tree structured problems parallel programming Java

Effect of radiative loss mechanisms on FIR thermometric parameters of Nd^(3+)-doped lithium tellurite glasses

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2024年第7期42卷 1250-1257,I0002页

作者： C.Y.morassuti A.P.L Silva L.A.O.Nunes S.m.Lima L.H.C.Andrade Optical and Photothermal Spectroscopy group(gEOF) Center for Studies in Natural Resources(CERNA)State University of Mato Grosso do Sul(UEMS)C.P.351DouradosMSBrazil Renato Archer Information Technology Center Dom Pedro I Highway(SP-65)Km 1436-Chácaras Campos dos AmaraisCampinasSPBrazil Institute of Physics of São Carlos University of São PauloSão CarlosSPBrazil

Nd^(3+)-doped tellurite glasses are promising materials for thermometers based on the fluorescence intensity ratio(FIR)***,at high Nd^(3+)concentrations,energy transfer(ET)processes such as optical reabsorption and cross-relaxation can affect the Nd^(3+)emission,which has been little explored in the ***,the present work investigated the use of Nd^(3+)-doped tellurite glass(samples doped with Nd^(3+)at 0.2 mol%,0.5 mol%,2.0 mol%,and 4.0 mol%)in fluorescence thermometers,in the temperature range from 299 to 371 *** results indicate a strong dependence of the FIR parameters on the Nd^(3+)concentration,due to changes in the emission band profiles caused by optical reabsorption of the Nd^(3+)emissions and cross-relaxation processes.A decrease of the relative sensitivity of the ratio^(4)F_(5/2)→^(4)I_(9/2)/^(4)F_(3/2)→^(4)I_(9/2)is observed for samples doped with higher amounts of Nd^(3+).The maximum relative sensitivity at 299 K is 3.00%/K,which is the highest value among the reported Nd^(3+)ions.

关键词： Nd^(3+)-doped tellurite glass Fluorescence intensity ratio Optical thermometry Judd-Ofelt Rare earths

characterization of the High-Strength mg–3Nd–0.5Zn Alloy Prepared by Thermomechanical Processing

在线全文

学校读者我要写书评

暂无评论

Acta metallurgica Sinica(English Letters) 2019年第3期32卷 321-331页

作者： Ji■í Kub■sek Drahomír Dvorsk■ Jozef Vesel■ Peter min■rik m■ria Zemkov■ Dalibor Vojtěch Department of metals and Corrosion Engineering Faculty of Chemical Technology University of Chemistry and Technology Prague Department of Physics of materials Charles University

magnesium alloys based on Nd and Zn are promising materials for both aviation industry and medical *** mechanical properties of these materials can be achieved by thermomechanical processing such as extrusion or rolling and by aging treatment, which can significantly strengthen the alloy. The question remains especially about the connection of texture strength created in the alloys based on the specific conditions of preparation. This work focuses on the mg–3 Nd–0.5 Zn magnesium alloy prepared by hot extrusion of the as-cast state at two different temperatures combined with heat pre-treatment. Extrusion ratio of 16 and rate of 0.2 mm/s at 350 and 400 °C were selected for material preparation. The structures of prepared materials were studied by scanning electron microscopy and transmission electron microscopy. The effect of microstructure on mechanical properties was evaluated. Obtained results revealed the strong effect of thermal pre-treatment on final microstructure and mechanical properties of extruded materials. The Hall–Petch relation between grain size and tensile yield strength has been suggested in this paper based on the literature review and presented data. The observed behavior strongly supports the fact that the Hall–Petch of extruded mg–3Nd–0.5 Zn alloys with different texture intensities cannot be clearly estimated and predicted. In addition, Hall–Petch relations presented in literature can be sufficiently obtained only for fraction of the mg–3Nd–0.5 Zn alloys.

关键词： mg–Nd–Zn alloys Extrusion Thermal treatment microstructure mechanical properties

Effect of tritium reduction in determining energy gain by using R-matrix method direct laser fusion in D-T reaction

在线全文

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2007年第3期18卷 129-136页

作者： S.N.HOSSEINI mOTLAgH sh.S.mOHAmADY m.Kh.mORADKHANI R.shAmSI Department of Physics Iran University of Science and Technology IranDepartment of PhysicsIran University of Science and Technology IranDepartment of PhysicsIran University of Science and Technology IranDepartment of Industrial EngineeringMazandaran University of Science and Technology Iran

The laser fusion criterion is known as the ρR-Criterion, also called high-gain condition. This parameter is temperature dependent and can be calculated by R-matrix method. This method is applied for determining improved fusion cross-section for the reactions T(d,n)4He, 3He(d,p)4He, D(d,p)T, D(d,n)3He. In this paper the time dependent reaction rate equations for fusion reaction T(d,n)4He are solved and by using the obtained results we computed the fu- sion power density, energy gain versus temperature and ρR-parameter. The obtained results show that a suitable com- bination may be a deuterium fraction fD=0.65 and fT=0.35 which would lead 30% reduction in the tritium content of the fuel mixture, and this choice would not change the energy gain value very much. Finally, the obtained energy gain for D-T reaction by using R-matrix is in good agreement with other theories.

关键词：氘氚反应激光聚合等离子体交叉断面

High Preformation SiC-AlN Composites

在线全文

学校读者我要写书评

暂无评论

Journal of materials Science & Technology 1997年第4期13卷 342-344页

作者： chen, Zm Tan, sh Zhang, ZQ Jiang, DL shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 200050 China

High performance SiC-AlN composites were fabricated by hot-pressing with Y2O3 as additive via liquid phase sintering. The SiC-AlN composites containing 5 vol. pet AIN exhibit superior mechanical properties with flexural strength, fracture toughness and Vickers hardness of 1131 mPa, 6.1 mPa.m(1/2) and 28.6 gPa respectively. microstructure observations indicate that the grain size of the composites is obviously inhibited due to the formation of solid solution. TEm-EDS analysis demonstrates the existence of the solid solution. In addition, subgrain boundaries induced by dislocations in the matrix SiC grains, seem to divide a large grain into numerous nano-sized small grains, which significantly increase the mechanical properties of the composites.

关键词： Ceramic matrix composites

Sliding Wear Behavior of a grey Cast Iron Surface Remelted by TIg

在线全文

学校读者我要写书评

暂无评论

Journal of materials Science & Technology 2009年第5期25卷 622-628页

作者： H.mohamadzadeh H.Saghafian sh.Kheirandish Department of metallurgy and materials Engineering Iran University of Science and TechnologyTehranIran

The sliding wear behavior of a grey cast iron surface remelted by tungsten inert gas （TIg） was studied and compared with the unremelted one in the current work. To evaluate the wear behavior a Pin-on-Disk wear test machine was used. Pins which were prepared from the samples with the remelted layers of different thicknesses of 1.2, 1.8, 2.5 and 3 turn were worn on an AISID3 steel counterface having a hardness of 63HRC under the applied loads of 54, 76 and gg N at a constant sliding velocity of 0.45 m/s. Scanning electron microscopy （SEm） equipped with energy dispersive X-ray analysis （EDS） and X-ray diffraction （XRD） techniques were used to characterize worn surface and subsurface and also wear debris obtained from the wear tests under different test conditions. Results showed that surface remelted grey cast iron have better wear properties for all applied normal loads in comparison with unremelted ones. microscopic studies on the worn surfaces and subsurfaces of samples revealed that dominant wear mechanism for surface remelted samples was mild oxidative, while it was severe for unremelted samples. Increasing remelted layer thickness and then forming grosser microstructure lead to a decline of wear properties, whereas lower thickness of remelted layer with finer microstructure due to having higher cooling rate through remelting process can withstand better against wear.

关键词： grey cast Iron Surface remelted Tungsten inert gas (TIg) Wear