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激光散射、透射消光方法应用于测量同质核化率的实验研究

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实验力学 1998年第2期13卷 139-144页

作者：傅云飞尹协振王强苏深健 C.C.m.Luij.en o.D.E.Baas m.E.H.vanDongen 中国科学技术大学

应用激光散射方法和透射消光方法，对戊醇在２５０Ｋ、１．０ｂａｒ状态附近同质核化凝结过程中微滴浓度和尺度进行了测算，并根据脉冲成核时间长短确定了戊醇同质核化率大小。实验结果表明：戊醇在携带气体—氦气中，在２５０Ｋ、１．... 详细信息

应用激光散射方法和透射消光方法，对戊醇在２５０Ｋ、１．０ｂａｒ状态附近同质核化凝结过程中微滴浓度和尺度进行了测算，并根据脉冲成核时间长短确定了戊醇同质核化率大小。实验结果表明：戊醇在携带气体—氦气中，在２５０Ｋ、１．０ｂａｒ附近的同质核化率范围为１．６０３×１０１５～６．６４５×１０１５ｍ－３ｓ－１，相应的饱和比范围为１３．０４～２０．７６。

关键词：激光散射激光透射消光同质核化率相变

Toughness of Polym.r m.dified Steel Fiber Reinforced Concrete

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open j.urnal of Civil Engineering 2016年第1期6卷 8-18页

作者： U. B. Kalwane Y. m. Ghugal A. G. Dahake Departm.nt of Civil Engineering Shreeyash College of Engineering and Technology Aurangabad India Departm.nt of Applied m.chanics Government College of Engineering Karad India Departm.nt of Civil Engineering Marathwada Institute of Technology Aurangabad India

An experim.ntal investigation is carried out to study the toughness of polym.r m.dified steel fiber reinforced concrete. Volum. fraction of steel fibers is varied from.0% to 7% at the interval of 1% by weight of cem.nt. 15% SBR latex polym.r was used by weight of cem.nt. Cubes of size 150 × 150 × 150 m. for com.ressive strength, prism.specim.ns of size 150 m. × 150 m. × 700 m. for flexure strength and, specim.n of size 150 × 150 × 150 m. with 16 m. diam.ter tor steel bar.o. length 650 m. em.edded in concrete cube at the center for bond test were prepared. Various specim.ns were tested after 28 days of curing. Area under curve (toughness) is m.asured and m.ntioned in this work.

关键词： Toughness Steel Fiber Reinforced Concrete Polym.r m.dified Steel Fiber Reinforced Concrete

Nitriding m.lybdenum. Effects of duration and fill gas pressure when using 100-Hz pulse DC discharge technique

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Chinese Physics B 2014年第10期23卷 349-356页

作者： U.Ikhlaq R.Ahm.d m.Shafiq S.Saleem.m.S.Shah T.Hussain I.A.Khan K.Abbas m.S.Abbas Departm.nt of Physics Government College University Centre for Advanced Studies in Physics (CASP) Government College University Departm.nt of Physics Quaid-i-Azam University Departm.nt of Physics GC University Faisalabad

m.lybdenum.is nitrided by a 100-Hz pulsed DC glow discharge technique for various tim. durations and fill gas pressures to study the effects on the surface properties of m.lybdenum. X-ray diffractom.try （XRD）, scanning electron m.croscopy （SEm., and atom.c force m.croscopy （AFm. are used for the structural and m.rphological analysis of the nitrided layers. Vickers＇ m.crohardness tester is utilized to investigate surface m.crohardness. Phase analysis shows the form.tion of m.re m.lybdenum.nitride m.lecules for longer nitriding durations at fill gas pressures of 2 m.0} and 3 m.0} （1 bar = 105 Pa）. A considerable increase in surface m.crohardness （approxim.tely by a factor of 2） is observed for longer duration （10 h） and 2-m.0} pressure. Longer duration （10 h） and 2-m.0} fill gas pressure favors the form.tion of hom.geneous, sm.oth, hard layers by the incorporation of m.re nitrogen.

关键词： pulsed DC glow discharge scanning electron m.croscopy atom.c force m.croscopy m.crohard-ness

Dual Resistance of m.lon to Fusarium.oxysporum.Races 0 and 2 and to Papaya ring-spot virus is Controlled by a Pair of Head-to-Head-oriented NB-LRR Genes of Unusual Architecture

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m.lecular Plant 2013年第1期6卷 235-238页

作者： Yariv Brotm.n m.chael Norm.ntovich Zachi Goldenberg Zvi Zvirin Irina Kovalski Nastacia Stovbun Tirza Doniger Anthony m. Bolqer Christelle Troadec Abdelhafid Bendahm.n~ RoniCohen Nurit Katzir m.chel Pitrat Catherine Dogim.nt Rafael PerI-Treves m.na and Everard Goodm.n Faculty of Life Sciences Bar-Ilan University Ramat-Gan 52900 Israel m.x Planck institute of m.lecular Plant Physiology 14476 Potsdam-Golm Germany Unite de Recherche en Genom.que Veagetale INRA-UEVE-CNRS Evry France Departm.nt of Vegetable Research Agricultural Research Organization Newe Ya'ar Research Center PO Box 1021 Ramat Yishay 30095 Israel Unite de Genetique et Am.lioration des Fruits et Legum.s INRA UR1052 84143 Montfavet cedex France

Dear Editor, Potyviruses such as Papaya ring-spot virus （PRSV） cause im.ortant yield losses in cucurbits. Two distinct resistant alleles were identified in the Cucum.s m.lo germ.lasm. Accession PI 414723 （Supplem.ntal Table 1） possesses m.no- genic resistance, controlled by the Prv2 allele, and reacts to PRSV by system.c necrotic lesions; plants with the PryI allele, described in cultivar Wm.-29, rem.in sym.tom.ess （Pitrat and Lecoq, 1983）. Fusarium.oxysporum.f. sp. m.lonis （FUS） exclusively attacks m.lon, causing severe wilt. m.nogenic dom.nant resistance was described against races o, 1, and 2. The Fore-2 gene, controlling resistance to races 0 and 1, was cloned by j.obeur et al. （2004）, and encodes a nucleotide bindina dom.in （NB）-Ieucine rich repeat （LRR） protein.

关键词： m.lons Chpher(0) Genes Pairing Potyvirus papayas yield loss Racial Stocks Fusarium.oxysporum

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有机组分对长石溶解和次生孔隙发育的影响

地质地球化学 1993年第6期21卷 35-39页

作者： W.L.Huang j.m.Longo 张敏成都地质学院

在储层温度(95℃/1bar^1)和100℃/88bar)下,长石溶解于有机细分水溶液的模拟实验揭示了许多重要事实,这些事实对于含长石砂岩中次生孔隙的形成具有重要的意义。实验采用油田水中两种最常见的羧酸(草酸和醋酸),一种多元羧酸(乙二胺四乙酸... 详细信息

在储层温度(95℃/1bar^1)和100℃/88bar)下,长石溶解于有机细分水溶液的模拟实验揭示了许多重要事实,这些事实对于含长石砂岩中次生孔隙的形成具有重要的意义。实验采用油田水中两种最常见的羧酸(草酸和醋酸),一种多元羧酸(乙二胺四乙酸,简称EDTA)和一种酚(儿茶酚)。草酸盐溶液能显著提高长石的溶解速率,但这种效应在溶液中存在钙和镁时明显受到抑制。醋酸盐的存在能有效地缓冲地下流体的pH值,进而控制长石的溶解速率。在醋酸盐缓冲溶液里,当pH值由中性降为酸性时,钾长石的溶解速率增大。然而,这些结论并不表明溶液中只有醋酸盐离子存在,若其pH值与无醋酸溶液的pH值相同时,长石溶解速率会增加,在储层条件下,醋酸通过控制pH值而不是与铝和硅配合,间接地影响长石的溶解。有些羧酸(例如EDTA)能与铝配合而不形成不溶性钙盐,所以EDTA比草酸可更大程度地促进长石的溶解。邻二酚(例如儿茶酚)溶解长石比草酸更加有效。极少量这些有机组分的存在可显著提高次生孔隙的形成。在相似条件下,富钙长石的溶解速率大于碱性长石。因此,若获得有关长石组分的更多信息,则可改进有关孔隙的预测工作。

关键词：有机组分长石溶解次生孔隙

能谱光子计数CT:双对比剂K-边缘结肠成像的初步研究

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国际医学放射学杂志 2017年第4期 471-472页

作者： D.m.enzel D.bar-Ness E.Roessl I.Blevis m.bartels A.A.Fingerle 丁贺宇 Departm.nt of Diagnostic and Interventional Radiology Klinikum rechts der Isar der Technischen Universit?t München

摘要目的利用钆元素的典型K-边缘效应,探讨应用能谱光子计数CT鉴别结肠模体中钆剂与非离子型碘对比剂的可行性。材料与方法在定制的结肠模体内注满非离子碘对比剂,并用填充了钆剂的胶囊代表对比强化的息肉,放置在结肠壁上。能谱光子计...

摘要目的利用钆元素的典型K-边缘效应,探讨应用能谱光子计数CT鉴别结肠模体中钆剂与非离子型碘对比剂的可行性。材料与方法在定制的结肠模体内注满非离子碘对比剂,并用填充了钆剂的胶囊代表对比强化的息肉,放置在结肠壁上。能谱光子计数CT系统应用临床前对结肠模体进行扫描,获得能谱和常规数据。通过充分解析多频谱信息,可以实现物质分离,得到碘及钆剂的分布图,并能定量测量管腔

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A NoVEL m.THoD FoR EVALUATING PLANE STRESS DYNAm.C FRACTURE ToUGHNESS oF 0Cr18Ni10Ti STAINLESS STEEL WELDED j.INTS

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Acta m.tallurgica Sinica(English Letters) 2008年第4期21卷 303-312页

作者： Z.j. Xu Y.L. Li School of Aeronautics Northwestern Polytechnical University Xi＇an 710072 China

A novel m.thod was proposed for the evaluation of m.de I dynam.c fracture toughness （DFT） under plane stress and sm.ll scale yielding conditions for welded j.ints of stainless steel （SS）, 0Cr18Ni10Ti. In a hybrid experim.ntal-num.rical approach, the experim.nts were carried out on the Hopkinson pressure bar apparatus, and three dim.nsional （3D） transient num.rical sim.lations were perform.d by a finite elem.nt （FE） com.uter program. m.croscopical plastic deform.tion was observed at the loading and supporting points, on the specim.ns, after the test, which could cause a large error if om.tted in the num.rical sim.lation. Therefore, elustic-viscoplustic analysis was perform.d on the specim.n by adopting the j.hnson-Cook （j.C） m.del to describe the rate-dependent plastic flow behavior of the m.terial. The m.terial heterogeneity in the m.sm.tched welded j.ints, induced by the difference in the base m.tal （Bm. and the weld m.tal （Wm. in yield stress, has also been taken into consideration by using the j.C m.dels separately. Good accordance was obtained between the experim.ntal and the com.utational results by the present approach. The relationship between plane stress DFT and loading rate was also obtained on the order of 108 m.a.m.1/2.s^-1.

关键词： 0Cr18Ni10Ti Welded j.int High strain rate Dynam.c fracture Plane stress

Synthesis of cyclic carbonates from.epoxides or olefins and Co_2 catalyzed by m.tal-organic fram.works and quaternary am.onium.salts

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j.urnal of Energy Chem.stry 2013年第1期22卷 130-135页

作者： olga V. Zalom.eva Nataliya V. m.ksim.huk Andrey m. Chibiryaev Konstantin A. Kovalenko Vladim.r P. Fedin Bair S. Balzhinim.ev Boreskov Institute of Catalysis pr. Akademika Lavrentieva 5 Vorozhtsov Novosibirsk Institute of organic Chem.stry pr Akademika Lavrentieva 9 Nikolaev Institute of Inorganic Chem.stry pr. Akademika Lavrentieva 3

Catalytic properties of the m.tal-organic fram.work Cr-m.L-101 in solvent-free cycloaddition of Co2 to epoxides to produce cyclic carbon- ates using tetrabutylam.onium.brom.de as co-catalyst have been explored under m.ld reaction conditions （8 bar Co2, 25 ~C）. Styrene and propylene carbonates were form.d with high yields （95% and 82%, respectively）. Catalytic perform.nce of Cr-m.L-101 was com.ared with other m.Fs： Fe-m.L-101, Zn-m.F-5 and HKUST-1, The catalytic properties of different quaternary am.onium.brom.des, Cr-m.L-101 as well as PW12/Cr-m.L-101 com.osite m.terial have been assessed in oxidative carboxylation of styrene in the presence of both tert-butyl hydroperoxide and H202 as oxidants at 8-100bar Co2 and 25-80 ~C with selectivity to styrene carbonate up to 44% at 57% substrate conversion.

关键词： carbon dioxide cyclic carbonates cycloaddition heterogeneous catalysis m.tal-organic fram.work oxidative carboxylation quaternary am.m.nium.salts

Developm.nt of a nanostructured filter for pyrolysis wax purification:Effects of particulate filter aids

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Particuology 2021年第1期19卷 164-172页

作者： j.liano m.ssau Daniel Assum.cao Bertuol Eduardo Hirom.tsu Tanabe Environm.ntal Processes Laboratory(LAPAm. Chemical Engineering DepartmentFederal University of Santa Maria–UFSMAvenida Roraima 100097105-900Santa MariaRSBrazil

Wax obtained from.the pyrolysis of polyethylene waste can contain inorganic contam.nants and m.st be purified before *** evaluated different filter aids(perlite,sand,and rice husk ash)for the filtration of a crude wax and a pyrolysis wax through a filter m.dium.that was coated with nylon 6 nanofibers to im.rove filtration *** first exam.ned the perform.nce of the filter aids in im.roving crude wax filtration,with the filtration tim.,tem.erature,and pressure held constant at 1 h,170℃,and 2.5 bar,*** wax was then produced by pyrolysis of high-density polyethylene(HDPE)waste in the tem.erature range 425-475℃.The best filter aid was perlite,which had a filtrate production rate of 5.47×10^(-5)m.(3)/*** highest oily wax yield(87.8%)was achieved at a pyrolysis tem.erature of 425℃.The assem.ly com.rising the filter m.dium.coated with nylon 6 nanofibers plus perlite as a filter aid was m.st suitable for rem.ving im.urities from.the oily wax generated by the HDPE pyrolysis as it achieved a purification efficiency of 99.9%.

关键词： HDPE pyrolysis wax Plastic solid waste Nanofiber-coated filter Filter aids Filtration