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双钝体涡街流量计流体振动特性的试验研究 被引量:9
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作者 彭杰纲 傅新 陈鹰 《机械工程学报》 EI CAS CSCD 北大核心 2002年第8期23-26,共4页
研究了双钝体旋涡脱离的流体动力学特性以及利用双钝体增强流体振动的最佳组合结构。给出了多种钝体组合结构的斯特劳哈尔数的试验结果,表明双钝体结构具有常定的斯特劳哈尔数。用50mm口径涡街流量计进行的试验证明,双钝体组合在一定的... 研究了双钝体旋涡脱离的流体动力学特性以及利用双钝体增强流体振动的最佳组合结构。给出了多种钝体组合结构的斯特劳哈尔数的试验结果,表明双钝体结构具有常定的斯特劳哈尔数。用50mm口径涡街流量计进行的试验证明,双钝体组合在一定的条件下能获得理想的旋涡重叠,从而增强流体的振动。在钝体的轴对称点上,还观察到强度和频率相同,相位相差180°的流体振动点,利用优化的双钝体结构和差动传感技术,研制出小流量灵敏度和抗干扰性能很好的新型旋涡流量计。 展开更多
关键词 涡街流量计 双钝旋涡脱离 振动 试验研究
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人眼晶体和晶体悬韧带及虹膜肌肉的胚胎发育(摘要)
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作者 李凤鸣 齐悦 《医学研究杂志》 1991年第8期24-25,共2页
本文在采用光镜对30例鸡胚60只眼晶体胚胎发育研究的基础上,采用光镜及透射电镜和扫描电镜,对131例发育不同阶段人胚的212只眼之晶体、晶体悬韧带以及瞳孔扩约肌和开大肌的胚胎发育及其超微结构进行了探讨。 1.本实验所观察人胚晶体发... 本文在采用光镜对30例鸡胚60只眼晶体胚胎发育研究的基础上,采用光镜及透射电镜和扫描电镜,对131例发育不同阶段人胚的212只眼之晶体、晶体悬韧带以及瞳孔扩约肌和开大肌的胚胎发育及其超微结构进行了探讨。 1.本实验所观察人胚晶体发育及超微结构变化与国外学者的研究结果基本相同,但为国内首次报道。晶体起源于体表外胚层,人胚晶体泡在胚胎33天已形成,脱离体表外胚层后,于第5周末原始晶体纤维开始生长, 展开更多
关键词 悬韧带 虹膜肌 眼晶 开大肌 超微结构 胚胎发育 脱离体 扩约肌 人胚 后囊
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1例右耳廓咬伤部分离体再植成功的护理
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作者 张庆芬 彭丽荣 《解放军医药杂志》 CAS 1994年第6期467-467,共1页
一患者,男,34岁。因与他人发生口角,被对方辎咬住耳廓,并将部分耳廓撕脱离体,当即从伤口处流出多量鲜红色血,伴有剧烈头痛,在当地县医院给予简单包扎伤口后,将病人及离体的右耳廓送往我院住院治疗。专科检查:右耳廓外侧缘上1/2部有约3cm... 一患者,男,34岁。因与他人发生口角,被对方辎咬住耳廓,并将部分耳廓撕脱离体,当即从伤口处流出多量鲜红色血,伴有剧烈头痛,在当地县医院给予简单包扎伤口后,将病人及离体的右耳廓送往我院住院治疗。专科检查:右耳廓外侧缘上1/2部有约3cm×1cm大小缺损,创缘不整齐,有血凝块覆盖。 展开更多
关键词 简单包扎 脱离体 剧烈头痛 血凝块 外侧缘 清创缝合术 血液循环 住院治疗 无菌注射器 高压氧治疗
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脱位离体牙再植的临床疗效观察
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作者 张葳 胡彦玲 《宁夏医学杂志》 CAS 2011年第4期367-369,共3页
目的总结脱位离体牙再植术的临床疗效。方法对174颗脱位牙再植术疗效进行回顾性分析。结果术后随访5年,174颗患牙成功再植151颗,总有效率达86%。结论年龄越小、离体时间越短,再植成功率越高;正确掌握适应证,严格遵守操作规范,以及合理... 目的总结脱位离体牙再植术的临床疗效。方法对174颗脱位牙再植术疗效进行回顾性分析。结果术后随访5年,174颗患牙成功再植151颗,总有效率达86%。结论年龄越小、离体时间越短,再植成功率越高;正确掌握适应证,严格遵守操作规范,以及合理的固定时间是提高疗效的关键因素。 展开更多
关键词 脱离 再植数
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左主支气管肿瘤切除术中瘤体脱落致呼吸衰竭1例
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作者 李松会 付明鹤 +1 位作者 郭桂珍 刘晓军 《河南医科大学学报》 1999年第3期141-142,共2页
关键词 支气管肿瘤 呼吸衰竭 肿瘤切除术 脱离
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材料力学与弹性力学异同点对比分析 被引量:1
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作者 卢小雨 董春亮 《内江科技》 2016年第8期77-77,14,共2页
本文从研究对象、研究方法、应力应变符号、一点的应力状态公式等方面对材料力学与弹性力学的异同点进行了对比分析,这既能帮助学生理解两者之间的异同点,同时也能达到温故而知新的效果,从而提高弹性力学的教学效果。
关键词 应力状态 对比分析 应力公式 教学效果 主平面 斜截面 切应力 常微分方程 杆件 脱离体
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优化供配电线路防雷系统研究 被引量:1
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作者 白广良 《现代商贸工业》 2010年第22期403-404,共2页
由于气候的变化,雷电频发,线路防雷愈来愈显得重要,根据兴隆台采油厂的近几年来线路雷电事故情况,通过采用新型防雷装置,加密避雷器安装点,解决避雷器被击穿后不能自动退出系统的问题,改进了原有的防雷设计,提高了防雷强度,减少了雷害... 由于气候的变化,雷电频发,线路防雷愈来愈显得重要,根据兴隆台采油厂的近几年来线路雷电事故情况,通过采用新型防雷装置,加密避雷器安装点,解决避雷器被击穿后不能自动退出系统的问题,改进了原有的防雷设计,提高了防雷强度,减少了雷害的发生和损坏程度,通过防雷系统的应用数据统计,计算经济效益,采油厂经济效益得到显著提高。 展开更多
关键词 氧化锌避雷器 防雷设计 脱离体 保护间距 接地
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应用超声生物显微镜检查及诊断青光眼术后睫状体脱离 被引量:1
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作者 李琳 李冬育 +2 位作者 赵春梅 石国强 单秀水 《眼科》 CAS 2001年第6期338-340,共3页
目的 :探讨青光眼术后睫状体脱离造成浅前房的形态学改变及其临床意义。方法 :应用眼科传统B超及超声生物显微镜 (ultrasoundbiomicroscopy ,UBM )对青光眼术后睫状体脱离的患眼、健眼形态进行观察并对其测量的相关数据进行统计学分析... 目的 :探讨青光眼术后睫状体脱离造成浅前房的形态学改变及其临床意义。方法 :应用眼科传统B超及超声生物显微镜 (ultrasoundbiomicroscopy ,UBM )对青光眼术后睫状体脱离的患眼、健眼形态进行观察并对其测量的相关数据进行统计学分析。结果 :UBM对B超不能诊断的睫状体脱离和脉络膜浅脱离 ,能特异性地进行检查诊断。其特征性表现为 :巩膜与睫状体间存在无回声区 ,睫状体位置前移、前旋 ,睫状体平坦部向眼中轴部位移动 ,部分患者可见睫状体平坦部呈层间分离 ,前房变浅的原因是睫状突向前扭转 ,导致虹膜根部膨隆 ,晶状体向前移位。所有睫状体脱离眼均为 36 0度全周脱离 ,而非某一象限的脱离 ,不伴有脉络膜脱离的单纯睫状体脱离所致的青光眼术后浅前房 ,一般不致前房完全消失 ,保守治疗可奏效。结论 :应用UBM检查可以对睫状体脱离造成的青光眼术后浅前房进行明确诊断 ,为临床治疗提供可靠依据。 展开更多
关键词 超声生物显微镜 眼状脱离 手术后并发症 青光眼
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中药抗肿瘤转移的分子机制研究进展 被引量:5
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作者 陈玉娟 王珺 《陕西中医》 2010年第6期762-764,共3页
关键词 抗肿瘤转移 中医中药 分子机制 微小转移灶 辨证论治 淋巴管内 脱离 周围组织
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铲运机的内力分析
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作者 刘国民 乔世珊 《华电技术》 CAS 1993年第6期9-11,16,共4页
在运动分析的基础上,对HL—2.5型铲运机作了内力分析。通过对组成机构的各个刚体列脱离体平衡方程,经整理得到求解所有约束力的封闭方程组,并以HL—2.5铲运机为例做了详细的数值计算,取得了理想结果。
关键词 铲运机 脱离体 封闭方程组 内力
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结构受力分析的基本方法——截面法的应用
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作者 李舒瑶 《黄河水利职业技术学院学报》 1993年第4期47-49,共3页
在构件、结构的设计计算中,必须进行受力分析。既使根据构造等要求按规范设计的构件、结构,进行强度、刚度的稳定性校核时也需要考虑危险截面的受力分析。在中专建筑力学教学中,学生感到难以掌握的部分就是结构的受力分析。
关键词 截面法 受力分析 力学教学 脱离体 危险截面 规范设计 支座反力 静定梁 受力图 静定结构
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曳光对无线电引信的影响研究 被引量:1
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作者 朱晓勤 张润录 张龙山 《探测与控制学报》 CSCD 北大核心 2008年第4期1-3,共3页
针对曳光榴弹的曳光火焰对无线电引信工作的影响,进行了靶场遥测和地面定量测试,发现曳光会使弹体天线引信射频输出端有数百毫伏噪声,绝大部分能量集中在100 Hz以下。采用脱离弹体天线的微波引信可防止曳光的影响;在弹体天线引信中增加... 针对曳光榴弹的曳光火焰对无线电引信工作的影响,进行了靶场遥测和地面定量测试,发现曳光会使弹体天线引信射频输出端有数百毫伏噪声,绝大部分能量集中在100 Hz以下。采用脱离弹体天线的微波引信可防止曳光的影响;在弹体天线引信中增加高通滤波,可有效克服曳光噪声对引信工作的影响。 展开更多
关键词 曳光榴弹 无线电引信 曳光弹火焰喷射噪声 脱离天线
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Desulfurization of Diesel Fuel by Extraction with [BF4]^--based Ionic Liquids 被引量:20
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作者 褚雪梅 胡玉峰 +5 位作者 李吉广 梁倩卿 刘艳升 张先明 彭效明 岳文佳 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2008年第6期881-884,共4页
The extractive removal of sulfur compounds (S-compounds) from Dongying and Liaohe diesel fuels with [BF4]^--based ionic liquids were systematically investigated. The results show that the absorption capacity of an i... The extractive removal of sulfur compounds (S-compounds) from Dongying and Liaohe diesel fuels with [BF4]^--based ionic liquids were systematically investigated. The results show that the absorption capacity of an ionic liquid for the S-compounds in diesel fuels relies on its structure and its size. In the case of the two examined diesel fuels, both elongating the cation tail length and increasing the mass ratio of ionic liquid/diesel fuel promote the desulfurization ability of the examined ionic liquids. The results also show that imidazolium-based ionic liquids display higher extraction efficiencies than pyridinium-based ionic liquids, presumably owing to the fact that the rings of the S-compounds are similar to the imidazolium head ring. With the 1 : 1 mass ratio of ionic liquid/diesel fuel, the rates of the first desulfurization of Dongying and Liaohe diesel fuels using [C8mim][BF4] amount to 29.96% and 39.76%, suggesting that [C8mim][BF4] is a promising extractant for desulfurization of these diesel fuels. 展开更多
关键词 DESULFURIZATION diesel fuel ionic liquid
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Catalytic Oxidative Desulfurization of Gasoline Using Vanadium(V)-substituted Polyoxometalate/H_2O_2/Ionic Liquid Emulsion System 被引量:2
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作者 Ge Jianhua Zhou Yuming +1 位作者 Yang Yong Xue Mengwei 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2012年第1期25-31,共7页
Aiming at deep desulfurization of gasoline,three amphiphilic catalysts [C18H37N(CH3)3]3+x [PMo12-xVxO40](x=1,2,or 3) were prepared and characterized.The amphiphilic vanadium(V)-substituted polyoxometalates were dissol... Aiming at deep desulfurization of gasoline,three amphiphilic catalysts [C18H37N(CH3)3]3+x [PMo12-xVxO40](x=1,2,or 3) were prepared and characterized.The amphiphilic vanadium(V)-substituted polyoxometalates were dissolved in water-immiscible ionic liquid([Bmim]PF6),forming a H2O2-in-[Bmim]PF6 emulsion desulfurization system with 30 m% H2O2 serving as the oxidant.The catalytic oxidation of sulfur-containing model oil has been studied in detail under various reaction conditions using this system.The ionic liquid emulsion system showed high catalytic oxidative activity in the treatment of commodity gasoline.Furthermore,the mechanism of catalytic oxidative desulfurization was also elaborated. 展开更多
关键词 DESULFURIZATION vanadium (V)-substituted polyoxometalates ionic liquid emulsion catalytic oxidation
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Ternary System of Fe-based Ionic Liquid,Ethanol and Water for Wet Flue Gas Desulfurization 被引量:5
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作者 解美莹 李沛沛 +2 位作者 郭惠锋 高丽霞 余江 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2012年第1期140-145,共6页
Fe-based ionic liquid (Fe-IL) was synthesized by mixing FeCl3·6H2O and 1-butyl-3-methylimidazolium chloride [Bmim]C1 in this paper. The phase diagram of a ternary Fe-IL, ethanol and water system was investigate... Fe-based ionic liquid (Fe-IL) was synthesized by mixing FeCl3·6H2O and 1-butyl-3-methylimidazolium chloride [Bmim]C1 in this paper. The phase diagram of a ternary Fe-IL, ethanol and water system was investigated to construct a ternary desulfurization solution for wet flue gas desulfurization. The effects of flow rate and concentration of SO2, reaction temperature, pH and Fe-IL fraction in aqueous desulfurization solution on the desulfiariza- tion efficiency were investigated. The results shows that the best composition of ternary desulfurization solution of Fe-IL, ethanol and water is 1 : 1.5 : 3 by volume ratio, and pH should be controlled at 2.0. Under such conditions, a desulfurization rate greater than 90% could be obtained. The product of sulfuric acid had inhibition effect on the wet desulfurization process. With applying this new ternary desulfurization solution, not only the catalyst Fe-IL can be recycled and reused, but also the product sulfuric acid can be separated directly from the ternary desulfurization system. 展开更多
关键词 Fe-based ionic liquid ternary phase diagram sulfide dioxide wet flue gas desulfurization
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Study on Removal of Naphthenic Acids from White Oil by[BMIM]Br-AlCl_3 被引量:2
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作者 Li Jing Sun Yu Shi Li (The State Key Laboratory of Chemical Engineering,East China University of Science and Technology, Shanghai 200237) 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2010年第4期46-51,共6页
The removal of acid compounds (naphthenates) from acidic oil with ionic liquids was systematically investigated. [BMIM]Br-AlCl3 was used to investigate the effect on deacidification of oil. Experimental results show... The removal of acid compounds (naphthenates) from acidic oil with ionic liquids was systematically investigated. [BMIM]Br-AlCl3 was used to investigate the effect on deacidification of oil. Experimental results showed that at a temperature of 323K with a molar ratio of AlCl3 to [BM1M]Br-AlCl3 of 0.2, and a mass ratio of IL to white oil of 4%, the deacidification rate could reach 75.9%. And a reaction time of 4 h was sufficient to achieve the goal. The study on reproducibility of catalytic performance of [BMIM]Br-AlCl3 showed the possibility of using the ionic liquid in the continuous catalytic reaction. 展开更多
关键词 naphthenic acid ionic liquid white oil DEACIDIFICATION
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Effect of water on extractive desulfurization of fuel oils using ionic liquids: A COSMO-RS and experimental study 被引量:3
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作者 Zhen Song Dian Yu +4 位作者 Qian Zeng Jingjing Zhang Hongye Cheng Lifang Chen Zhiwen Qi 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2017年第2期159-165,共7页
When evaluating ionic liquids (ILs) for extractive desulfurization (EDS) of fuel oils, the inevitable presence of water in the system may have a significant and in many cases strongly negative effect. However, few... When evaluating ionic liquids (ILs) for extractive desulfurization (EDS) of fuel oils, the inevitable presence of water in the system may have a significant and in many cases strongly negative effect. However, few studies have considered this particular issue and a promoted water effect on EDS is scarcely reported. In this work, COSMO-RS was firstly employed to calculate the capacity and selectivity for EDS of various IL/H20 mixtures, which cover different IL characters and a wide water concentration range. Experiments were then conducted with a representative IL [C4MIM]IH2P04], whose stable and even promoted extraction performance with a small amount of water was suggested by COSMO-RS. Through analyses of the desulfurization ratio, the cross- solubility and the water content in the desulfurized fuel, the promoted effect of water within a certain range (〈 10 wt%) was experimentally demonstrated. Moreover, such effect of water was explained combining the viscosity, the solvent-solute interactions and the COSMO-RS based analysis. 展开更多
关键词 Extractive desulfudzationIonic liquidsCOSMO-RSWater content effect
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Photosynthetic responses of thalli and isolated protoplasts of Bryopsis hypnoides(Bryopsidales,Chlorophyta)during dehydration 被引量:1
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作者 吕芳 王广策 靳皓琛 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第2期334-342,共9页
Bryopsis kypnoides Lamouroux is a unique intertidal siphonous green alga whose extruded protoplasm can aggregate spontaneously in seawater to form numerous new cells that can develop into mature algal thalli. In this ... Bryopsis kypnoides Lamouroux is a unique intertidal siphonous green alga whose extruded protoplasm can aggregate spontaneously in seawater to form numerous new cells that can develop into mature algal thalli. In this study, the photosynthetic responses during dehydration of both the thalli and protoplasts isolated from B. kypnoides were measured using a Dual-PAM (pulse amplitude modulation)-100 fluorometer. The results show that the photosynthetic rates of B. kypnoides thalli were maintained for an initial period, beyond which continued desiccation resulted in reduced rates of PSI and PSII. However, the photosynthetic performances of the isolated protoplasts dehydrated in air (CO2 concentration 600-700 mg/L) showed a slight increase of Y(II) at 20% water loss, but the rates decreased thereafter with declining water content. When protoplasts were dehydrated in CO2 deficient conditions (CO2 concentration 40-80 mg/L), the values of Y(II) declined steadily with increased dehydration without an initial rise. These results indicated that the thalli and isolated protoplasts of this alga can utilize CO2 in ambient air effectively, and the photosynthetic performances of the isolated protoplasts were significantly different from that of the thalli during dehydration. Thus the protoplasts may be an excellent system for the study of stress tolerance. 展开更多
关键词 Bryopsis hypnoides chlorophyll fluorescence DEHYDRATION PROTOPLASTS pulse amplifiedmodulation fluorescence system
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Removal of Trace Olefins from Aromatics by Catalytic Alkylation Using 1-Alkyl-3-methylimidazolium Bromochloroaluminate Catalyst
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作者 Sun Yu Shi Li(State Key Laboratory of Chemical Engineering,East China University of Science and Technology,Shanghai 200237) 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2011年第2期14-18,共5页
Removal of trace olefins from aromatic liquids had been investigated in the presence of various ionic liquids like 1-ethyl-3-methylimidazoliurn bromochloroaluminate (EMIMBr-AlCl3), 1-butyl-3-methylimidazolium bromoc... Removal of trace olefins from aromatic liquids had been investigated in the presence of various ionic liquids like 1-ethyl-3-methylimidazoliurn bromochloroaluminate (EMIMBr-AlCl3), 1-butyl-3-methylimidazolium bromochloroaluminate (BMIMBr-AlCl3), l-hexyl-3-methylimidazolium bromochloroaluminate (HMIMBr-AlCl3), and 1-octyl-3-methylimidazolium bromochloroaluminate (OMIMBr-A1C13). It was found that the longer the alkyl chain of ionic liquid cations was, the higher the olefins conversion would be. OMIMBr-AlCl3 (with 0.67 molar fraction of AlCl3) had an obvious performance on olefins removal. The influences of various reaction parameters such as the dosage of catalyst, the reaction temperature, and the reaction time on the reaction catalyzed by OMIMBr-AlCl3 were investigated. Under optimum reaction conditions, a higher than 99% conversion of olefins was achieved. The preliminary results revealed that the process could save time, consume less energy, separate products easier, and cause less pollution to the environment. 展开更多
关键词 ionic liquids olefins removal 1-alkyl-3-methylimidazolium bromochloroaluminate AROMATIC
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Support Effects on Thiophene Hydrodesulfurization over Co-Mo-Ni/Al_2O_3 and Co-Mo-Ni/TiO_2-Al_2O_3 Catalysts 被引量:7
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作者 刘超 周志明 +2 位作者 黄永利 程振民 袁渭康 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第4期383-391,共9页
A carbon-based sulfonated catalyst was prepared by direct sulfonation and carbonization (in moderate conditions:200 &#176;C, 12 h) of red liquor solids, a by-product of paper-making process. The prepared sulfonate... A carbon-based sulfonated catalyst was prepared by direct sulfonation and carbonization (in moderate conditions:200 &#176;C, 12 h) of red liquor solids, a by-product of paper-making process. The prepared sulfonated cata-lyst (SC) had aromatic structure, composed of carbon enriched inner core, and oxygen-containing (SO3H, COOH, OH) groups enriched surface. The SO3H, COOH, OH groups amounted to 0.74 mmol·g^-1, 0.78 mmol·g^-1, 2.18 mmol·g^-1, respectively. The fresh SC showed much higher catalytic activity than that of the traditional solid acid catalysts (strong-acid 732 cation exchange resin, hydrogen type zeolite socony mobile-five (HZSM-5), sulfated zir-conia) in esterification of oleic acid. SC was deactivated during the reactions, through the mechanisms of leaching of sulfonated species and formation of sulfonate esters. Two regeneration methods were developed, and the catalytic activity can be mostly regenerated by regeneration Method 1 and be fully regenerated by regeneration Method 2, respectively. 展开更多
关键词 HYDRODESULFURIZATION SUPPORT hierarchically macro-/mesoporous structure AL2O3 TiO2-Al2O3
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