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复配气相缓蚀剂对多种金属大气腐蚀的综合保护作用研究
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作者 韩兴存 林德雨 张金伟 《材料保护》 CAS CSCD 北大核心 2019年第1期40-43,112共5页
为了应对海洋大气环境中电子设备容易被腐蚀的难题,制备了一种复配气相缓蚀剂。通过半封闭空间挥发减量试验、缓蚀膜疏水性表征、模拟环境和海洋大气环境试验等评价了复配气相缓蚀剂对钢、T2紫铜、黄铜、银、铝等电子设备常用金属的气... 为了应对海洋大气环境中电子设备容易被腐蚀的难题,制备了一种复配气相缓蚀剂。通过半封闭空间挥发减量试验、缓蚀膜疏水性表征、模拟环境和海洋大气环境试验等评价了复配气相缓蚀剂对钢、T2紫铜、黄铜、银、铝等电子设备常用金属的气相缓蚀性能。结果表明:复配气相缓蚀剂对以上金属均具有显著的缓蚀作用,其中对钢的缓蚀率为86.9%,对T2紫铜为58.7%,对黄铜为96.2%,对银和铝在模拟腐蚀环境中具有一级气相缓蚀能力,是一种性能优良的电子设备多金属大气腐蚀综合防护材料。 展开更多
关键词 气相缓蚀剂 复配 大气腐蚀 电子设备
不同级配类型增韧型环氧沥青混合料路用性能研究
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作者 刘攀 李璐 +1 位作者 盛兴跃 郝增恒 《公路》 北大核心 2019年第3期38-42,共5页
针对环氧沥青材料在钢桥面铺装中的应用,制备了增韧型环氧沥青混合料,并研究了5种级配类型对增韧型环氧沥青混合料马歇尔性能、高温稳定性、低温抗裂性、水稳定性能、抗疲劳性能及抗滑性能的影响。试验结果表明,级配类型对增韧型环氧沥... 针对环氧沥青材料在钢桥面铺装中的应用,制备了增韧型环氧沥青混合料,并研究了5种级配类型对增韧型环氧沥青混合料马歇尔性能、高温稳定性、低温抗裂性、水稳定性能、抗疲劳性能及抗滑性能的影响。试验结果表明,级配类型对增韧型环氧沥青混合料的抗滑性能影响较大,对混合料的其他路用性能影响较小,不同级配类型下的混合料均具有良好的路用性能。增韧型环氧沥青混合料能够满足钢桥面铺装对材料性能的要求。 展开更多
关键词 增韧型环氧沥青 混合料 级配 路用性能 钢桥面铺装
硅藻精土改性沥青混合料抗水侵蚀性能研究 预览
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作者 梁高荣 陈其龙 覃峰 《西部交通科技》 2019年第5期1-4,共4页
文章通过将硅藻土提纯得到硅藻精土并按不同比例掺入到沥青中,进行沥青混合料马歇尔试验、浸水马歇尔试验、冻融劈裂试验以及浸水车辙试验研究。试验结果表明:通过马歇尔试验得出,当硅藻精土的掺配比为13%时,沥青混合料各项指标达到最... 文章通过将硅藻土提纯得到硅藻精土并按不同比例掺入到沥青中,进行沥青混合料马歇尔试验、浸水马歇尔试验、冻融劈裂试验以及浸水车辙试验研究。试验结果表明:通过马歇尔试验得出,当硅藻精土的掺配比为13%时,沥青混合料各项指标达到最优效果;硅藻精土掺量为13%时,浸水马歇尔残留稳定度达到的峰值是基质沥青混合料浸水马歇尔残留稳定度的1.05倍,说明加入硅藻精土后可以有效提高混合料的力学特性;在冻融劈裂试验中,硅藻精土改性沥青混合料的劈裂强度较70^#沥青混合料的劈裂强度明显增强,其中掺入13%硅藻精土改性沥青混合料的劈裂强度较70^#沥青混合料的劈裂强度提高了近6.5%;在浸水车辙试验中,掺入硅藻精土的沥青混合料变形量均比基质沥青混合料小,动稳定度均比基质沥青大,说明加入硅藻精土改性剂后可以有效提高混合料的抗变形能力。综合得出13%掺量的硅藻精土改性沥青混合料的抗水侵蚀性能效果最佳。 展开更多
关键词 硅藻精土 改性沥青 混合料 抗水侵蚀 性能研究
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Eutectic mixture promoted CO2 sorption on MgO-TiO2 composite at elevated temperature
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作者 Vishwanath Hiremath Monica Louise T.Trivino Jeong Gil Seo 《环境科学学报:英文版》 SCIE EI CAS CSCD 2019年第2期80-88,共9页
The development of carbon dioxide (CO2) sorbents that can operate at elevated temperatures is significant for the advancement of pre-combustion capture technologies. Recently, promoter-based systems composed of alkali... The development of carbon dioxide (CO2) sorbents that can operate at elevated temperatures is significant for the advancement of pre-combustion capture technologies. Recently, promoter-based systems composed of alkali/alkaline earth metal nitrates and/or carbonates have been considered as next-generation solid sorbents due to their improved CO2 uptake and kinetics. However, obtaining stable MgO sorbents against temperature swing regeneration still remained challenging. Herein, we report MgO-TiO2 solid sorbents promoted by eutectic mixture (KNO3 and LiNO3) for elevated temperature CO2 sorption. The developed sorbents show improved CO2 sorption capacity, which may be attributed to the alternative CO2 sorption pathway provided by the ionization of highly dispersed MgO in the eutectic mixture. The MgO-TiO2 framework was also shown to assist in retaining the MgO configuration by constraining its interaction with CO2. Furthermore, it is demonstrated that constructing composite structures is essential to improve the CO2 sorption characteristics, mainly recyclability, at elevated temperatures. The developed promoter integrated sorbents showed exceptionally high CO2 sorption capacity of > 30 wt.% at an elevated temperature (300°C) with pronounced stability under temperature swing operation. 展开更多
关键词 MgO-TiO2 COMPOSITE Elevated temperature CO2 capture EUTECTIC mixture promoter MGO stability
Weed growth,herbicide efficacy,and rice productivity in dry seeded paddy field under different wheat stubble management methods 预览
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作者 Muhammad Zia-Ul-Haq Abdul Khaliq +4 位作者 Qiang Sheng Amar Matloob Saddam Hussain Saba Fatima Zeshan Aslam 《农业科学学报:英文版》 SCIE CAS CSCD 2019年第4期907-926,共20页
To ascertain the influence of wheat stubble management options and chemical weed control methods on weed growth and productivity of dry direct-seeded fine rice,a two years’field study was undertaken at the Agronomic ... To ascertain the influence of wheat stubble management options and chemical weed control methods on weed growth and productivity of dry direct-seeded fine rice,a two years’field study was undertaken at the Agronomic Research Farm,University of Agriculture,Faisalabad,Pakistan in 2013 and 2014.Different wheat stubble management methods,viz.,incorporation,burning and retention were executed during seed-bed preparation.While,herbicide treatments comprised of a weed check,weed free,pendimethalin followed by tank mixture of fenoxaprop p-ethyl+ethoxysulfuron ethyl,and bispyribac sodium followed by tank mixture of fenoxaprop p-ethyl+ethoxysulfuron ethyl.Results revealed that weed control efficacy of both herbicide treatments ranged from 84 to 94%.Herbicide treatments significantly reduced weed density(88–90%)and dry weight(86–88%),while improved the rice growth attributes compared with weed check.Application of bispyribac sodium followed by tank mixture of fenoxaprop p-ethyl+ethoxysulfuron ethyl in stubble retention recorded 226 and 273%increase in kernel yield over weedy check in 2013 and 2014,respectively.In stubble incorporation,pendimethalin followed by tank mixture of fenoxaprop p-ethyl+ethoxysulfuron ethyl was more effective in increasing(256–293%)rice yields over weedy check.Among different treatment combinations,the maximum net benefits(1 397.49–1 472.22 USD ha–1),net returns(636–700 USD ha–1),benefit cost ratio(1.77–1.83)and marginal rate of return(2 187–2 330%)were recorded with the application of bispyribac sodium followed by fenoxaprop p-ethyl+ethoxysulfuron ethyl in stubble retention.In crux,application of bispyribac sodium followed by tank mixture of fenoxaprop p-ethyl+ethoxysulfuron ethyl in stubble retention is efficient approach to control weeds,and get maximum rice productivity and net economic returns under dry seeded system. 展开更多
关键词 HERBICIDE mixture weedy check STUBBLE management WEEDS density and DRY weight DSR
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振动弦法测定制冷剂/冷冻机油混合介质的黏度 预览
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作者 李潘源 毕胜山 《合成润滑材料》 CAS 2019年第3期30-33,共4页
运动黏度是润滑油关键的技术指标之一,在一定程度上可以反映润滑油的润滑性,但仅依据冷冻机油的运动黏度 却无法准确判断冷冻机的润滑状况。因为在冷冻机中冷冻机油与制冷剂相互溶解形成制冷剂/冷冻机油混合介质,冷冻机油 被稀释,运动... 运动黏度是润滑油关键的技术指标之一,在一定程度上可以反映润滑油的润滑性,但仅依据冷冻机油的运动黏度 却无法准确判断冷冻机的润滑状况。因为在冷冻机中冷冻机油与制冷剂相互溶解形成制冷剂/冷冻机油混合介质,冷冻机油 被稀释,运动黏度显著下降,润滑性能也会随着下降。为了预测冷冻机油的润滑性,测定实际工况条件下制冷剂/冷冻机油混 合介质的运动黏度十分必要。为此开发了测定制冷剂/冷冻机油混合介质运动黏度的振动弦法,该方法的相对偏差在±3.0% 以内,可为预测冷冻机油在冷冻机中的润滑性以及为研制新型的冷冻机油提供帮助。 展开更多
关键词 振动弦法 冷冻机油 制冷剂 混合介质 润滑性 运动黏度
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热碱-分步酶水解-厌氧消化工艺处理秸秆畜粪混合物料及其甲烷高值化条件
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作者 卞爱琴 远野 +5 位作者 张璐璐 付强 陈天明 何磊 丁成 王爱杰 《环境科学》 EI CAS CSCD 北大核心 2019年第2期1003-1010,共8页
为获得秸秆畜粪混合物料在厌氧消化过程中的甲烷高值化产出,提出了一种新型'热碱-分步酶水解-厌氧消化'组合工艺.以玉米秸秆和牛粪混合物料作为实验对象,考察物料中纤维素、半纤维素、蛋白质获得高溶出效率的热碱预处理条件;分... 为获得秸秆畜粪混合物料在厌氧消化过程中的甲烷高值化产出,提出了一种新型'热碱-分步酶水解-厌氧消化'组合工艺.以玉米秸秆和牛粪混合物料作为实验对象,考察物料中纤维素、半纤维素、蛋白质获得高溶出效率的热碱预处理条件;分步投加纤维素酶和蛋白酶的剂量及水解时间;热碱预处理后的混合浆液和热碱-酶水解后的混合水解液厌氧消化甲烷产率及产气周期.结果表明,在80℃和0. 5%Na OH碱用量条件下,纤维素、半纤维素和蛋白质的溶出效率(%TS)最高,与未预处理相比(对照组),分别提高24. 84%、12. 24%和8. 92%;分步酶水解的过程和条件为:先投加80 U·g-1的纤维素酶水解18 h,再投加20 U·g-1的蛋白酶水解4 h,纤维素和蛋白质的水解效率可分别达到74. 08%和74. 01%,获得的水解液中糖类提高12~32倍;在厌氧消化阶段,热碱-酶水解后的水解液甲烷产量最高值可达750 m L·h-1,产气周期50 h,相比于热碱预处理后的底物消化(对照组),产甲烷效率提高了约14倍,产气周期缩短了约17 d.热碱-酶水解预处理能有效地解除混合物料厌氧消化过程的水解限速,研究结果可以为开发高效的农业废弃物能源高值化利用技术提供参考依据. 展开更多
关键词 秸秆畜粪 混合物料 热碱预处理 酶水解 厌氧消化 甲烷产率
爆炸气体或蒸气混合物的类别判定 预览
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作者 黄旭 《石油化工设计》 CAS 2019年第2期73-74,I0004共3页
石油化工企业的生产装置在生产过程中会产生大量爆炸危险气体,需要选择合理的防爆电气及其他设备以保证工艺的装置安全生产。根据现行国内、外标准规范的要求,结合工程示例,研究分析了可燃性爆炸危险介质混合物的分类方法,给出对于含有... 石油化工企业的生产装置在生产过程中会产生大量爆炸危险气体,需要选择合理的防爆电气及其他设备以保证工艺的装置安全生产。根据现行国内、外标准规范的要求,结合工程示例,研究分析了可燃性爆炸危险介质混合物的分类方法,给出对于含有氢气的爆炸危险气体的计算公式,并得出不是含有氢气的可燃性爆炸危险介质混合物都应为ⅡC的分类。 展开更多
关键词 爆炸 混合物 最大试验安全间隙 最小点燃电流比
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Turbulent mechanisms in open channel sediment-laden flows 预览
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作者 Hai Huang Hongwu Zhang +1 位作者 Deyu Zhong Yinglong JZhang 《国际泥沙研究:英文版》 SCIE 2019年第6期550-563,共14页
The effects of turbulence onwater-sediment mixtures is a critical issue in studying sediment-laden flows.The sediment concentrations and particle inertia play a significant role in the effects of turbulence on mixture... The effects of turbulence onwater-sediment mixtures is a critical issue in studying sediment-laden flows.The sediment concentrations and particle inertia play a significant role in the effects of turbulence on mixtures.A two-phase mixture turbulence model was applied to investigate the turbulence mechanisms affecting sediment-laden flows.The two-phase mixture turbulence model takes into account the complicated mechanisms arising from interphase transfer of turbulent kinetic energy,particle collisions,and stratification.The turbulence in sediment-laden flows is the result of the interaction of four factors,i.e.the production,dissipation,diffusion,and inter-phase transfer of turbulent kinetic energy of mixtures.The turbulence production and dissipation are two dominant processes which balance the turbulent kinetic energy of mixtures.The turbulence production represents turbulence intensity,while the inter-phase transfer of turbulent kinetic energy denotes the effect of particles on the turbulence of sediment-laden flows.Although,the magnitude of the inter-phase interaction term is much less than that of the turbulence production and dissipation terms,due to an approximate local balance between production and dissipation of the turbulent kinetic energy,even the small order of the inter-phase interaction has a significant impact on the turbulent balance of sediment-laden flows.The presence of particles plays a duel role in the turbulence dissipation of mixtures:both promotion and suppression.An important parameter used to determine the turbulent viscosity of mixtures,which is constant in clear water,is the function of the sediment concentration and particle inertia in sediment-laden flows. 展开更多
关键词 TURBULENCE modulation TWO-PHASE MIXTURE TURBULENCE model Suspended SEDIMENT Open CHANNELS
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啶酰菌胺与烯肟菌酯复配对灰葡萄孢的毒力增效作用
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作者 牛慧慧 赵建江 +3 位作者 韩秀英 王文桥 毕秋艳 马志强 《农药》 CAS CSCD 北大核心 2019年第1期61-64,共4页
[目的]明确啶酰菌胺与烯肟菌酯复配对灰葡萄孢的毒力增效作用。[方法]采用菌丝生长速率法测定2种药不同配比对灰葡萄孢的毒力;采用孢子萌发法和离体叶片法测定最佳组合对灰葡萄孢的毒力并进行田间试验。[结果] 2者以6∶1复配时增效最明... [目的]明确啶酰菌胺与烯肟菌酯复配对灰葡萄孢的毒力增效作用。[方法]采用菌丝生长速率法测定2种药不同配比对灰葡萄孢的毒力;采用孢子萌发法和离体叶片法测定最佳组合对灰葡萄孢的毒力并进行田间试验。[结果] 2者以6∶1复配时增效最明显,对孢子萌发和其他菌株的菌落扩展,对灰霉病的保护和治疗作用均显示增效;在剂量为250~350 g a.i./hm^2时,对灰霉病的防效高于80%。[结论]啶酰菌胺与烯肟菌酯复配对灰霉病防效高,可用于灰霉病的防治。 展开更多
关键词 灰葡萄孢 啶酰菌胺 烯肟菌酯 混配 增效作用
Tribo-charging of binary mixtures composed of coarse and fine particles in gas-solid pipe flow
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作者 Haifeng Wang Farzam Fotovat +1 位作者 Xiaotao T. Bi John R. Grace 《中国颗粒学报:英文版》 SCIE EI CAS CSCD 2019年第2期101-109,共9页
Experiments were conducted to investigate the effect of adding fines on the tribo-charging of coarse glass beads. Four types of fines, i.e., copper, stainless steel, uncoated and silver-coated fine glass beads, mixed ... Experiments were conducted to investigate the effect of adding fines on the tribo-charging of coarse glass beads. Four types of fines, i.e., copper, stainless steel, uncoated and silver-coated fine glass beads, mixed w让h 240-830 μm glass beads were conveyed by air through a stainless-steel spiral pipe acting as a tribo-charger. Regardless of the type or electrical conductivity of the fine particles tested, adding small amounts of fines (up to 10wt%) to coarse glass beads resulted in a sharp increase in the mass and surface charge densities of the particles. In gen eral, the profiles of the mass and surface charge den sides of the fine-coarse particle mixtures as a function of the mixture composition were determined by the relative magnitude of contact potential differences and the total surface areas of all the comp on ents. The domi nant particle tri bo-electrification mecha nism switched from coarse particle-wall con tacts to fine particle-wall contacts when the fines weight percentage in the mixture exceeded 10%. A model was developed to predict the mass charge density of bi nary mixtures as a function of the mixture composition. 展开更多
关键词 Tribo-charging ELECTROSTATICS FINE particles BINARY MIXTURE GAS-SOLID flow
烧结混合料水分自动控制系统的开发及应用
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作者 谭奇兵 文虹力 +2 位作者 蒋杰 黄俊程 李宗社 《烧结球团》 北大核心 2019年第2期18-23,68共7页
混合料水分在烧结过程中有着制粒和导热的作用,水分的控制一直是烧结生产中关注的重点。为了更好地对混合料水分进行控制,开发了一种以红外水分分析仪、微波水分分析仪及变频水泵等作为硬件基础,以PID控制、前馈控制、反馈控制等来实现... 混合料水分在烧结过程中有着制粒和导热的作用,水分的控制一直是烧结生产中关注的重点。为了更好地对混合料水分进行控制,开发了一种以红外水分分析仪、微波水分分析仪及变频水泵等作为硬件基础,以PID控制、前馈控制、反馈控制等来实现水分实时监测和闭环自动调节的水分自动控制系统。主要从硬件组成及工作原理、设计、应用效果等方面对该系统进行了阐述,并对其在柳钢3~#360 m^2烧结机的应用情况进行了介绍。该系统投入使用后,水分目标值稳定率(±0.2%)由85.3%提高到95.7%,烧结矿转鼓指数稳定率(>75%)由95.6%提高到98.9%,FeO稳定率(±1.0%)由96.7%提高到了98.8%,利用系数由1.478t/(m^2·h)提高到了1.537t/(m^2·h),有效地减少了混合料水分的波动,改善了烧结矿的产、质量指标。 展开更多
关键词 烧结 混合料 水分 自动控制 开发及应用
Effects of seed mixture sowing with transgenic Bt rice and its parental line on the population dynamics of target stemborers and leafrollers, and non-target planthoppers
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作者 Zhuo Li Li-Kun Li +3 位作者 Bin Liu Long Wang Megha N. Parajulee Fa-Jun Chen 《昆虫科学:英文版》 SCIE CAS CSCD 2019年第4期777-794,共18页
The widespread planting of insect-resistant crops has caused a dramatic shift in agricultural landscapes, thus raising concerns about the potential impacts on both target and non-target pests. In this study, we examin... The widespread planting of insect-resistant crops has caused a dramatic shift in agricultural landscapes, thus raising concerns about the potential impacts on both target and non-target pests. In this study, we examined the potential effects of intra-specific seed mixture sowing with transgenic Bt rice (Bt) and its parental non-transgenic line (Nt)(100% Bt rice [Bt100], 5% Nt+95% Bt [Nt05Bt95], 10% Nt+90% Bt [Nt|0Bt90], 20% Nt+80% Bt [Nt2oBtso], 40% Nt+60% Bt [Nt4oBt6O] and 100% Nt rice [Ntjoo]) on target and non-target pests in a 2-year field trial in southern China. The occurrence of target pests, Sesamia inf evens. Chilo suppressalis and Cnaphalocrocis medinalis, decreased with the increased ratio of Bt rice, and the mixture ratios with more than 90% Bt rice (Btjoo and Nt()5Bt95) significantly increased the pest suppression efficiency, with the lowest occurrences of non-target planthoppers, Nilaparvata lugens and Sogatella jurcijera in Ntioo and NtosBtgs. Furthermore, there were no significant differences in 1000?grain dry weight and grain dry weight per 100 plants between Btjoo and NtosBtgs,Seed mixture sowing of Bt rice with <10%(especially 5%) of its parent line was sufficient to overcome potential compliance issues that exist with the use of block or structured refuge to provide most effective control of both target and non-target pests without compromising the grain yield. It is also expected that the strategy of seed mixture sowing with transgenic Bt rice and the nontransgenic parental line would provide rice yield stability while decreasing the insecticide use frequency in rice production. 展开更多
关键词 cultivar diversity occurrence and damage seed mixture SOWING TARGET and non-target pests TRANSGENIC Bt rice yield
Optimizing the compressive strength of concrete containing micro-silica, nano-silica, and polypropylene fibers using extreme vertices mixture design
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作者 Fatemeh ZAHIRI Hamid ESKANDARI-NADDAF 《结构与土木工程前沿:英文版》 EI CSCD 2019年第4期821-830,共10页
Many studies have evaluated the effects of additives such as nano-silica (NS), micro-silica (MS) and polymer fibers on optimizing the mechanical properties of concrete, such as compressive strength. Nowadays, with pro... Many studies have evaluated the effects of additives such as nano-silica (NS), micro-silica (MS) and polymer fibers on optimizing the mechanical properties of concrete, such as compressive strength. Nowadays, with progress in cement industry provides, it has become possible to produce cement type I with strength classes of 32.5, 42.5, and 52.5 MPa. On the one hand, the microstructure of cement has changed, and modified by NS, MS, and polymers;therefore it is very important to determine the optimal percentage of each additives for those CSCs. In this study, 12 mix designs containing different percentages of MS, NS, and polymer fibers in three cement strength classes(CSCs)(32.5, 42.5, and 52.5 MPa) were designed and constructed based on the mixture method. Results indicated the sensitivity of each CSCs can be different on the NS or MS in compressive strength of concrete. Consequently, strength classes have a significant effect on the amount of MS and NS in mix design of concrete. While, polymer fibers don’t have significant effect in compressive strength considering CSCs. 展开更多
关键词 mixture method COMPRESSIVE strength NANO-SILICA micro-silica polypropylene fibers
Extending the EMMS/bubbling model to fluidization of binary particle mixture:Formulation and steady-state validation
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作者 Nouman Ahmad Yujie Tian +3 位作者 Bona Lu Kun Hong Haifeng Wang Wei Wang 《中国化学工程学报:英文版》 SCIE EI CAS CSCD 2019年第1期54-62,共9页
The EMMS/bubbling model originally proposed for fluidization of monodisperse particles is extended to fluidization of binary particle mixture in this study.The dense and dilute phases are considered to comprise of two... The EMMS/bubbling model originally proposed for fluidization of monodisperse particles is extended to fluidization of binary particle mixture in this study.The dense and dilute phases are considered to comprise of two types of particles differing in size and/or density.Governing equations and the stability condition are then formulated and solved by using an optimization numerical scheme.The effects of bubble diameter are first investigated and a suitable bubble diameter correlation is chosen.Preliminary validation for steady state behavior shows the extended model can fairly capture the overall hydrodynamic behaviors in terms of volume fraction of bubbles and average bed voidage for both monodisperse and binary particle systems.This encourages us to integrate this model with CFD for more validations in the future. 展开更多
关键词 EMMS BINARY mixture FLUIDIZATION MESOSCALE structure
高速公路Superpave路面施工中的应用要点 预览
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作者 李岩青 《山西建筑》 2019年第7期158-160,共3页
对Superpave设计方法与马歇尔设计方法进行了比较,介绍了Superpave混合料的特性和优势,分析了Superpave混合料在拌制、铺摊、碾压等各工序中质量控制的要点,说明了该路面具有的良好路用性能,是解决路面早期损坏特别是车辙病害的有效途径。
关键词 SUPERPAVE路面 混合料 碾压
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冷拌环氧沥青混合料路用性能的室内试验
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作者 王俊彦 李洋 +3 位作者 顾帆 杨梦林 陈东风 顾伟峰 《材料科学与工程学报》 CAS CSCD 北大核心 2019年第2期296-299,338共5页
通过室内试验研究了三种国产冷拌环氧沥青胶结料的粘度-时间变化规律和力学性质,以及混合料的高低温性能、抗水损害和疲劳性能等路用性能。研究结果表明,冷拌环氧沥青胶结料性能优良,其混合料具有优良的路用性能,适合钢桥面铺装。
关键词 公路钢桥面铺装 冷拌环氧沥青 混合料 力学性质 路用性能
Failure behavior of soil-rock mixture slopes based on centrifuge model test
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作者 WANG Teng ZHANG Ga 《山地科学学报:英文版》 SCIE CSCD 2019年第8期1928-1942,共15页
The stability of soil-rock mixtures(SRMs) that widely distributed in slopes is of significant concern for slope safety evaluation and disaster prevention. The failure behavior of SRM slopes under surface loading condi... The stability of soil-rock mixtures(SRMs) that widely distributed in slopes is of significant concern for slope safety evaluation and disaster prevention. The failure behavior of SRM slopes under surface loading conditions was investigated through a series of centrifuge model tests considering various volumetric gravel contents. The displacement field of the slope was determined with image-based displacement system to observe the deformation of the soil and the movement of the block during loading in the tests. The test results showed that the ultimate bearing capacity and the stiffness of SRM slopes increased evidently when the volumetric block content exceeded a threshold value. Moreover, there were more evident slips around the blocks in the SRM slope. The microscopic analysis of the block motion showed that the rotation of the blocks could aggravate the deformation localization to facilitate the development of the slip surface. The high correlation between the rotation of the key blocks and the slope failure indicated that the blocks became the dominant load-bearing medium that influenced the slope failure. The blocks in the sliding body formed a chain to bear the load and change the displacement distribution of the adjacent matrix sand through the block rotation. 展开更多
关键词 Soil ROCK MIXTURE SLOPE stability SLOPE FAILURE CENTRIFUGE model test
1D TOCSY技术应用于氨基醇混合物的选择性检测
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作者 张何 黄桂兰 袁铃 《分析试验室》 CAS CSCD 北大核心 2019年第2期222-229,共8页
对一维全相关谱(1D TOCSY)技术分析高背景干扰下3种痕量氨基醇混合物(三乙醇胺、N-甲基二乙醇胺、2-二异丙基氨基乙醇)进行了研究。优化了脉冲序列、整形脉冲、混合时间等关键实验参数,实现对3种痕量氨基醇化合物相关峰的指认和结构鉴定... 对一维全相关谱(1D TOCSY)技术分析高背景干扰下3种痕量氨基醇混合物(三乙醇胺、N-甲基二乙醇胺、2-二异丙基氨基乙醇)进行了研究。优化了脉冲序列、整形脉冲、混合时间等关键实验参数,实现对3种痕量氨基醇化合物相关峰的指认和结构鉴定,方法检测限为5μg/mL。在三乙醇胺的氢谱信号完全被掩盖或干扰的情况下,讨论了利用1D TOCSY定量分析三乙醇胺的可行性。将建立的1D TOCSY方法成功应用于国际禁止化学武器组织(OPCW)第42次水平考试的盲样分析。与1D NOESY方法相比,1D TOCSY方法在实现选择性检测的同时,具有更高的检测灵敏度,有利于痕量分析。 展开更多
关键词 选择性激发 一维全相关谱 氨基醇 混合物
Intertidal area classification with generalized extreme value distribution and Markov random field in quad-polarimetric synthetic aperture radar imagery
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作者 Ting-ting JIN Xiao-qiang SHE +1 位作者 Xiao-lan QIU Bin LEI 《信息与电子工程前沿:英文版》 SCIE EI CSCD 2019年第2期253-264,共12页
Classification of intertidal area in synthetic aperture radar(SAR) images is an important yet challenging issue when considering the complicatedly and dramatically changing features of tidal fluctuation. The difficult... Classification of intertidal area in synthetic aperture radar(SAR) images is an important yet challenging issue when considering the complicatedly and dramatically changing features of tidal fluctuation. The difficulty of intertidal area classification is compounded because a high proportion of this area is frequently flooded by water, making statistical modeling methods with spatial contextual information often ineffective. Because polarimetric entropy and anisotropy play significant roles in characterizing intertidal areas, in this paper we propose a novel unsupervised contextual classification algorithm. The key point of the method is to combine the generalized extreme value(GEV) statistical model of the polarization features and the Markov random field(MRF) for contextual smoothing. A goodness-of-fit test is added to determine the significance of the components of the statistical model. The final classification results are obtained by effectively combining the results of polarimetric entropy and anisotropy. Experimental results of the polarimetric data obtained by the Chinese Gaofen-3 SAR satellite demonstrate the feasibility and superiority of the proposed classification algorithm. 展开更多
关键词 INTERTIDAL CLASSIFICATION Polarimetric synthetic APERTURE radar Finite mixture MODEL MARKOV random field Generalized extreme value MODEL
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