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Killing Effect of Mixed Fumigation of Phosphine and Carbon Dioxide on Eggs of Lasioderma serricorne F. 被引量:2
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作者 彭涛 刘师伟 +2 位作者 谭琳 余兴江 郭年梅 《Agricultural Science & Technology》 CAS 2015年第12期2730-2732,共3页
[Objective] This study aimed to investigate the killing effect of mixed fumi- gation of phosphine and carbon dioxide on eggs of Lasioderma serricorne F. [Method] The outside-storage phosphine generator was placed in a... [Objective] This study aimed to investigate the killing effect of mixed fumi- gation of phosphine and carbon dioxide on eggs of Lasioderma serricorne F. [Method] The outside-storage phosphine generator was placed in a tabernacled smoke box, and the mortality rates of L. serricome F. eggs in the smoke box under conditions of different aluminium phosphide usage amount and different fumigation time were studied. In addition, the times needed by tabernacle and smoke box cen- ter to reach the phosphine concentration peak were recorded. [Result] The optimum conditions for killing the eggs of L. serricorne were as follows: temperature of (27± 2) ℃, relatively humidity of (45±5)%, aluminium phosphide usage amount of 1.5 g/m3 and effective exposure time of 96 h. The killing effect of mixed fumigation of phos- phine and carbon dioxide was increased with the extension of fumigation time. The increased usage amount of aluminium phosphide showed no significant effect on killing effect. The tabernacle space and smoke box center all required relatively short time to reach the phosphine concentration peak. If the tabernacle had a good airtightness, the overall fumigation time could be shortened. [Conclusion] The fumi- gation method is reliable, and it can be used for the control of L. serricorne F. in tobacco storage. 展开更多
关键词 mixed fumigation of phosphine and carbon dioxide Lasioderma serri- come F. Egg Fumigation time Mortality rate
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Mechanical Properties and ITZ Microstructure of Recycled Aggregate Concrete Using Carbonated Recycled Coarse Aggregate 被引量:7
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作者 伍君勇 张云升 +2 位作者 ZHU Pinghua FENG Jincai 胡坤 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2018年第3期648-653,共6页
The effect of carbonation treatment and mixing method on the mechanical properties and interfacial transition zone(ITZ) properties of recycled aggregate concrete(RAC) was investigated. Properties of recycled concr... The effect of carbonation treatment and mixing method on the mechanical properties and interfacial transition zone(ITZ) properties of recycled aggregate concrete(RAC) was investigated. Properties of recycled concrete aggregate(RCA) were tested firstly. Then, five types of concretes were made and slump of fresh concrete was measured immediately after mixing. Compressive strength and splitting tensile strength of hardened concrete were measured at 28 d. Meanwhile, the microstructure of RAC was analyzed by backscattered electron(BSE) image. It was found that the water absorption ratio of carbonated recycled concrete aggregate(CRCA) was much lower when compared to the untreated RCA. Comparatively, the apparent density of CRCA was not significantly modified. The concrete strength results indicate that the mix CRAC-2 prepared with CRCA by adopting two-stage mixing approach shows the highest compressive strength value compared to the other mixes. The microstructural analysis demonstrate that the mix CRAC-2 has a much denser old ITZ than the untreated RAC because of the chemical reaction between CO2 and the hydration products of RCA. This study confirms that the ITZ microstructure of RAC can be efficiently modified by carbonation treatment of RCA and encourages broadening the application of construction and demolition wastes. 展开更多
关键词 recycled aggregate concrete compressive strength interfacial transition zone carbonation treatment two-stage mixing approach back scattered electron
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Closed-form internal impedance model and characterization of mixed carbon nanotube bundles for three-dimensional integrated circuits
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作者 卢启军 朱樟明 +2 位作者 杨银堂 丁瑞雪 李跃进 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第1期520-525,共6页
Based on the complex effective conductivity method, a closed-form expression for the internal impedance of mixed carbon nanotube (CNT) bundles, in which the number of CNTs for a given diameter follows a Gaussian dis... Based on the complex effective conductivity method, a closed-form expression for the internal impedance of mixed carbon nanotube (CNT) bundles, in which the number of CNTs for a given diameter follows a Gaussian distribution, is proposed in this paper. It can appropriately capture the skin effect as well as the temperature effect of mixed CNT bundles. The results of the closed-form expression and the numerical calculation are compared with various mean diameters, standard deviations, and temperatures. It is shown that the proposed model has very high accuracy in the whole frequency range considered, with maximum errors of 1% and 2.3% for the resistance and the internal inductance, respectively. Moreover, by using the proposed model, the high-frequency electrical characteristics of mixed CNT bundles are deeply analyzed to provide helpful design guidelines for their application in future high-performance three-dimensional integrated circuits. 展开更多
关键词 mixed carbon nanotube (CNT) bundle internal impedance closed-form expression complex ef-fective conductivity method
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Mapping Soil Organic Carbon Stocks of Northeastern China Using Expert Knowledge and GIS-based Methods 被引量:2
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作者 SONG Xiaodong LIU Feng +4 位作者 JU Bing ZHI Junjun LI Decheng ZHAO Yuguo ZHANG Ganlin 《Chinese Geographical Science》 SCIE CSCD 2017年第4期516-528,共13页
The main aim of this paper was to calculate soil organic carbon stock(SOCS) with consideration of the pedogenetic horizons using expert knowledge and GIS-based methods in northeastern China.A novel prediction process ... The main aim of this paper was to calculate soil organic carbon stock(SOCS) with consideration of the pedogenetic horizons using expert knowledge and GIS-based methods in northeastern China.A novel prediction process was presented and was referred to as model-then-calculate with respect to the variable thicknesses of soil horizons(MCV).The model-then-calculate with fixed-thickness(MCF),soil profile statistics(SPS),pedological professional knowledge-based(PKB) and vegetation type-based(Veg) methods were carried out for comparison.With respect to the similar pedological information,nine common layers from topsoil to bedrock were grouped in the MCV.Validation results suggested that the MCV method generated better performance than the other methods considered.For the comparison of polygon based approaches,the Veg method generated better accuracy than both SPS and PKB,as limited soil data were incorporated.Additional prediction of the pedogenetic horizons within MCV benefitted the regional SOCS estimation and provided information for future soil classification and understanding of soil functions.The intermediate product,that is,horizon thickness maps were fluctuant enough and reflected many details in space.The linear mixed model indicated that mean annual air temperature(MAAT) was the most important predictor for the SOCS simulation.The minimal residual of the linear mixed models was achieved in the vegetation type-based model,whereas the maximal residual was fitted in the soil type-based model.About 95% of SOCS could be found in Argosols,Cambosols and Isohumosols.The largest SOCS was found in the croplands with vegetation of Triticum aestivum L.,Sorghum bicolor(L.) Moench,Glycine max(L.) Merr.,Zea mays L.and Setaria italica(L.) P.Beauv. 展开更多
关键词 soil organic carbon stock model-then-calculate random forest linear mixed model northeastern China
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Sintering Behaviour of Al_2O_3-SiC-C Ramming Mix
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作者 WUXingrong CAOFeng 《China's Refractories》 CAS 2004年第2期33-36,共4页
Silicon fines, boron acid solid powders and microfine SiO 2 as sintering agents were incorporated into Al 2O 3-SiC-C ramming mix in order to investigated their effects on the microstructure, mechanical properties a... Silicon fines, boron acid solid powders and microfine SiO 2 as sintering agents were incorporated into Al 2O 3-SiC-C ramming mix in order to investigated their effects on the microstructure, mechanical properties and sintering behavior of the ramming mix. Results show that all the three agents could improved both densification and mehanical properties markedly, compared to that of non-agent specimens and the effect of the composite of boron acid solid powders and microfine SiO 2 is the best. The oxidation resistance increased with the addition of agents, which is supported by densification. Microstructures showed that agent powders could fill pores or produce liquid phases at high temperature, therefore, improve the sintering of the ramming mix. 展开更多
关键词 ALUMINA Silicon carbide Carbon ramming mix Sintering agent DENSIFICATION Oxidation resistance
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Characterization of CeO_2-ZrO_2 mixed oxides prepared by two different co-precipitation methods 被引量:6
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作者 岳梅 崔梅生 +2 位作者 张娜 龙志奇 黄小卫 《Journal of Rare Earths》 SCIE EI CAS CSCD 2013年第3期251-256,共6页
A series of cerium zirconium mixed oxides were prepared by two co-precipitation methods using magnesium hydrogen carbonate (MHC) and mixed ammonia-ammonia hydrogen carbonate (AAHC) as precipitant respectively. The... A series of cerium zirconium mixed oxides were prepared by two co-precipitation methods using magnesium hydrogen carbonate (MHC) and mixed ammonia-ammonia hydrogen carbonate (AAHC) as precipitant respectively. The crystal structure, BET surface area and morphology of the produced cerium zirconium mixed oxides were characterized by X-ray diffraction (XRD), Bru- mauer-Emmett-Teller (BET) and scanning electron microscopy (SEM) techniques. The reduction-oxidation behavior and oxygen storage capacity (OSC) performance were also studied by temperature programmed reduction (TPR) and oxygen pulse chemical adsorption methods. The XRD results demonstrated that the cerium zirconium mixed oxides obtained by both methods possessed struc ture of cubic solid solution phase. The fresh surface area calcinated at 600 ℃, aged surface area after 1000 ℃and OSC at 500 ℃ of cerium zirconium mixed oxides were determined to be 89.337, 34.784 ma/g, and 567 pmol O2/g for MHC method and 122.010, 46.307 m2/g, and 665 pmol O2/g for AAHC method, respectively. 展开更多
关键词 cerium zirconium mixed oxide magnesium hydrogen carbonate mixed ammonia-ammonia hydrogen carbonate co-pre-cipitation rare earths
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Production of Poly(3-Hydroxybutyrate-co-3-Hydroxyhexanoate) Using Aeromonas hydrophila 4AK4 Grown in Mixed Carbon Source 被引量:1
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作者 张瑾 张广 +2 位作者 陈金春 华秀英 陈国强 《Tsinghua Science and Technology》 SCIE EI CAS 2002年第4期393-397,共5页
Aeromonas hydrophila 4AK4 was grown on mixed substrates of soybean oil and lauric acid for the production of polyhydroxyalkanoate copolymer consisting of 3 hydroxybutyrate (3HB) and 3 hydroxyhexanoate (3HHx). A m... Aeromonas hydrophila 4AK4 was grown on mixed substrates of soybean oil and lauric acid for the production of polyhydroxyalkanoate copolymer consisting of 3 hydroxybutyrate (3HB) and 3 hydroxyhexanoate (3HHx). A maximal poly(3 hydroxybutyrate co 3 hydroxyhexanoate) (PHBHHx) content of 49.13% in dry cells was obtained in a shake flask culture. PHBHHx of 6.26 g/L was produced in a fermentation experiment over 48 h on a sole carbon source containing 100 g/L soybean oil, while 12.40 g/L PHBHHx was produced on a mixed carbon source containing 80 g/L soybean and 20 g/L lauric acid over the same period of time, resulting in a polyhydroxyalkanoate (PHA) productivity of 0.25 g/(L·h). The results show that mixed carbon sources are suitable for industrialized production of PHBHHx from A. hydrophila 4AK4, as the mixed carbon sources also overcome the foaming problem that occurs when lauric acid is employed as a sole carbon source in PHBHHx production. 展开更多
关键词 polyhydroxyalkanoates (PHAs) poly(3 hydroxybutyrate co 3 hydroxyhexanoate) (PHBHHx) Aeromonas hydrophila mixed carbon source
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Clumped Isotope Analysis of Calcite and Dolomite Mixtures Using Selective Acid Extraction
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作者 Sen Li Andrew Schauer +3 位作者 Alexis Licht Jie Liang Kate Huntington Kangning Peng 《Journal of Earth Science》 SCIE CAS CSCD 2023年第3期726-734,共9页
Acid extraction methods have been used in the last half century to selectively extract the CO_(2)produced from different carbonate minerals in mixed samples.However,these methods are often time-consuming and labor int... Acid extraction methods have been used in the last half century to selectively extract the CO_(2)produced from different carbonate minerals in mixed samples.However,these methods are often time-consuming and labor intensive.Their application to clumped isotope(Δ47)analysis has not been demonstrated.We propose here an acid extraction method with phosphoric acid for bulk stable and clumped isotope analysis that treats mixtures of calcite and dolomite the same regardless of the proportional composition.CO_(2)evolved from calcite is extracted by allowing a reaction with phosphoric acid to proceed for 10 min at 50℃.We then extract CO_(2)evolved from dolomite by rapid ramping the acid temperature from 50 to 90℃and allowing the reaction to complete.The experimental results show that our method yields accurate calcite and dolomiteΔ_(47)values from mixed samples under different proportional compositions.Our method also displays equal or higher accuracy for calciteδ^(13)C and dolomiteδ^(13)C andδ^(18)O values from mixtures when compared to previous studies.Our approach exhibits higher sample throughput than previous methods,is adequate for clumped isotopic analysis and simplifies the reaction progression from over 24 h to less than 2 h,while maintaining relatively high isotopic obtaining accuracy.It yet poorly resolves calciteδ18O values,as found with previous methods. 展开更多
关键词 mixed carbonate samples selective acid extraction acid fractionation correction clumped isotope bulk isotope CALCITE DOLOMITE
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A facile template free synthesis of porous carbon nanospheres with high capacitive performance 被引量:1
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作者 Junyu Piao Deshan Bin +3 位作者 Shuyi Duan Xijie Lin Dong Zhang Anmin Cao 《Science China Chemistry》 SCIE EI CAS CSCD 2018年第5期538-544,共7页
Porous carbon nanospheres have been widely used in different fields such as electric devices, catalysts, and water treatment. Here we will introduce a template-free process for the preparation of porous carbon nanosph... Porous carbon nanospheres have been widely used in different fields such as electric devices, catalysts, and water treatment. Here we will introduce a template-free process for the preparation of porous carbon nanospheres starting from a direct 3-aminophenol formaldehyde polymerization in a mixed solution. We identify that the addition of different alcohols, particularly ethanol and nbutanol, is able to change the growth habit of the polymer nanospheres and introduce a favorable inner compositional homogeneity for the preparation of porous structure. After the carbonization of the polymer nanospheres, the obtained porous carbon exhibits promising electrochemical performance when used as electrode material in super capacitor. 展开更多
关键词 porous carbon nanospheres alcohol mixed solvent template-free super capacitors
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On-Chip Fabrication of Carbon Nanoparticle–Chitosan Composite Membrane
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作者 Weiping Ding Cheng Liang +2 位作者 Sijie Sun Liqun He Dayong Gao 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2015年第11期1087-1093,共7页
The on-chip fabrication of a carbon nanoparticle-chitosan composite membrane (i.e. a sorbent membrane or a mixed matrix membrane) using laminar flow-based interfacial deprotonation technology was presented in this p... The on-chip fabrication of a carbon nanoparticle-chitosan composite membrane (i.e. a sorbent membrane or a mixed matrix membrane) using laminar flow-based interfacial deprotonation technology was presented in this paper. In addition, the effects of carbon nanoparticles and reactant flow rates on membrane formation were investigated. Finally, the permeability and adsorption capacities of the membrane were discussed. During fabrication, an acidic chitosan solution and a basic buffer solution that contained carbon nanoparticles were introduced into a microchannel. At the flow interface, a freestanding composite membrane with embedded carbon nanoparticles was formed due to the deprotonation of the chitosan molecules. The membrane growth gradually stopped with time from upstream to downstream and the thickness of the membrane increased rapidly and then slowly along the reactant flow direction. The formation of the membrane was divided into two stages. The average growth rate in the first stage was significantly larger than the average growth rate in the second stage. Carbon nanoparticles in the basic solution acted as nucleating agents and made the membrane formation much easier. As the flow rate of the chitosan solution increased, the averaged membrane thickness and the membrane hydraulic permeability initially increased and then decreased. Because of the addition of carbon nanoparticles, the formed membrane had adsorption abilities. The carbon nanoparticle-chitosan composite membrane that was fabricated in this study could be employed for simultaneous adsorption and dialysis in microdevices in the future. 展开更多
关键词 On-chip fabrication Composite membrane Carbon nanoparticle Chitosan Interracial deprotonation mixed matrix membrane
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