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Synergistic Effect in Mixed Capillary Gas Chromatographic Stationap Phases Containing Heptakis(2,3,6-tri-o-pentyl)-β-cyclodextrin and Dibenzo-18-crown-6 被引量:1
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作者 Li Ming YUAN Ruo Nong FU +3 位作者 Xue Xian CHEN Shi Hong GUl Rong Ji DAI (Chemistry Department of Yunnan Normal University.Kunming 650092)(Department of Chemical Engineering.Beijing institute of Technology,BEijing 100081)(Solar Energy Research Institute ofyunna 《Chinese Chemical Letters》 SCIE CAS CSCD 1999年第3期223-226,共4页
used-silical capillary columns containing heptakis(2、3、6-tri-o-pentyl)-β-cyclodextrinand dibenzo-18-crown-6 were prepared.By studying the selectivity of mixed stationary phases forsome solute pairs.as well a... used-silical capillary columns containing heptakis(2、3、6-tri-o-pentyl)-β-cyclodextrinand dibenzo-18-crown-6 were prepared.By studying the selectivity of mixed stationary phases forsome solute pairs.as well as comparing with the heptakis(2.3、6-tri-O-pentyl)-β-cyclodextrin and thedibenzo-18-crown-6 used as individual stationary phase、the synergistic effects were observed.These effects were affected by the column temperature.mixed ratio and linear velocity of carrier gas. 展开更多
关键词 gas chromatography mixed stationary phase synergistic effect heptakis(2.3.6-tri-o-pentyl)-β-cyclodextrin DIBEnZO-18-CROWn-6
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A comprehensive review on Mg-based materials as filler in mixed matrix membranes for CO_(2)separation
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作者 Payam Veisi Alireza Askari Arash Fattah-alhosseini 《Journal of Magnesium and Alloys》 2025年第2期539-561,共23页
The crisis of excessive increase in CO_(2)emissions has quickly become a serious issue and requires low-cost and bio-compatible solutions.The employee of membrane technology for CO_(2)gas separation has garnered signi... The crisis of excessive increase in CO_(2)emissions has quickly become a serious issue and requires low-cost and bio-compatible solutions.The employee of membrane technology for CO_(2)gas separation has garnered significant interest among researchers.However,this method encounters challenges related to selectivity and permeability.Therefore,modifying and reinforcing the polymer membranes to improve gas separation performance seems essential.Among the various methods for polymer membrane modification,modification with magnesium-based fillers to prepare a mixed matrix membrane(MMM)is considered an efficient method.Owing to magnesium metal's low weight,low density,high strength,and good selectivity,magnesium-based materials(Mg-based materials)have more porosity,higher available surface area,more adsorption sites,lighter weight,and more gas absorption tendency than other fillers,which makes them an attractive choice for the preparation of gas separation MMMs.This research deals with the introduction of Mg-based materials,various methods of synthesis of Mg-based materials,different methods of introducing Mg-based materials into the membrane matrix,and their effect on the performance of MMMs in CO_(2)gas separation applications.Therefore,this review can provide researchers with light horizons in using the high potential of Mg-based materials as efficient fillers in MMMs to achieve excellent permeability and selectivity and generally improve their performance in CO_(2)gas separation applications. 展开更多
关键词 Mg-based materials Mg-based fillers mixed matrix membrane(mmm) Co2 separation gas separation applications
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Recovery of iron from copper slag via modified roasting in CO-CO2 mixed gas and magnetic separation 被引量:5
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作者 Ping-guo Jiang Jin-sheng Liu +2 位作者 Yi-yu Xiao Xiao-heng Tan Wen-jie Liu 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2020年第7期796-806,共11页
A novel technology,modified roasting in CO-CO2 mixed gas and magnetic separation,was presented to recover iron from copper slag.The effects of various parameters such as dosage of flux(CaO),gas flowrate of CO and CO2,... A novel technology,modified roasting in CO-CO2 mixed gas and magnetic separation,was presented to recover iron from copper slag.The effects of various parameters such as dosage of flux(CaO),gas flowrate of CO and CO2,roasting temperature,roasting time,particle size of modified slag and magnetic flux density on the oxidized modification and magnetic separation were investigated by comparison of the X-ray diffraction patterns and iron recovery ratio.The optimum conditions for recovering iron by oxidizing roasting and magnetic separation are as follows:calcium oxide content of 25 wt.%,mixed gas flow rates of CO2 and CO of 180 and 20 mL/min,oxidizing roasting at 1323 K for 2 h,grinding the modified slag to 38.5-25.0μm and magnetic separation at 170 mT.The mineralogical and microstructural characteristics of modified slag revealed that the iron-bearing minerals in the copper slag were oxidized,the generated magnetite grew into large particles,and the silicate in copper slag was combined with calcium oxide to form calcium silicate.Finally,the iron-bearing concentrate with an iron grade of 54.79%and iron recovery ratio of 80.14%was effectively obtained. 展开更多
关键词 Copper slag CO-CO2 mixed gas Modified roasting Magnetic separation Iron recovery ratio
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Distinguished discriminatory separation of CO2 from its methane-containing gas mixture via PEBAX mixed matrix membrane 被引量:1
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作者 Pouria Abbasszadeh Gamali Abbass Kazemi +4 位作者 Reza Zadmard Morteza Jalali Anjareghi Azadeh Rezakhani Reza Rahighi Mohammad Madani 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第1期73-80,共8页
Highly selective separation of CO_2 from its methane-containing binary gas mixture can be achieved by using Poly(ether-block-amide)(PEBAX)mixed matrix membranes(MMMs).According to FESEM and AFM analyses,silica-based n... Highly selective separation of CO_2 from its methane-containing binary gas mixture can be achieved by using Poly(ether-block-amide)(PEBAX)mixed matrix membranes(MMMs).According to FESEM and AFM analyses,silica-based nanoparticles were homogenously integrated within the polymer matrix,facilitating penetration of CO_2 through the membrane while acting as barrier for methane gas.The membrane containing 4.6 wt% fumed silica(FS)(PEBAX/4.6 wt%FS)exhibits astonishing selectivity results where binary gas mixture of CO_2/CH_4 was used as feed gas.As detected by gas chromatography,in the permeate side,data showed a significant increase of CO_2 permeance,while CH_4 transport through the mixed matrix membrane was not detectable.Moreover,PEBAX/4.6 wt%FS greatly exceeds the Robeson limit.According to data reported on CO_2/CH_4 gas pair separation in the literature,the results achieved in this work are beyond those data reported in the literature,particularly when PEBAX/4.6 wt%FS membrane was utilized. 展开更多
关键词 mixed matrix membrane Fumed silica Binary gas mixture CO2/CH4 separation
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Effects of precursor moisture and inert N_2 atmosphere calcinations on structure and properties of alumina modified CeZrLaNd mixed oxides 被引量:3
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作者 Meisheng Cui Zhizhe Zhai +3 位作者 Hao Wang Yongke Hou Yongqi Zhang Xiaowei Huang 《Journal of Rare Earths》 SCIE EI CAS CSCD 2019年第6期609-616,共8页
CeO_2-ZrO_2 mixed oxides are widely used in the three-way catalysts due to their unique reversible oxygen storage and release capacity. Large surface area, high oxygen storage capacity and good thermal stability of ce... CeO_2-ZrO_2 mixed oxides are widely used in the three-way catalysts due to their unique reversible oxygen storage and release capacity. Large surface area, high oxygen storage capacity and good thermal stability of cerium zirconium mixed oxides are the key properties for the automotive catalysts so as to meet the strict emission regulations. In this work, alumina modified CeZrLaNd mixed oxides were prepared by a co-precipitation method. The effects of moisture in precursor and inert N2 atmosphere during calcinations on the structure and properties were investigated by Brunauer-Emmett-Teller(BET) surface area measurements, X-ray diffraction(XRD), scanning electron microscopy(SEM), transmission electron microscopy(TEM), hydrogen temperature-programmed reduction(H_2-TPR), oxygen storage capacity(OSC), Raman spectroscopy, and X-ray photoelectron spectroscopy(XPS). The results show that the moisture in precursor during calcinations increases the crystal grain size of the cerium zirconium mixed oxides, improving the thermal stability. And the aged surface area of sample after being calcined at1000 ℃ for 4 h reaches 68.8 m^2/g(5.7% increase compared with the common sample). The inert N2 atmosphere endows a great pore-enlarging effect, which leads to high fresh surface area of 148.9 m2/g(13.5% increase compared with the common sample) and big pore volume of 0.5705 mL/g. The redox and oxygen storage capacity are also improved by inert N2 atmosphere with high OSC value of 241.06μmolO_2/g(41.3% increase compared with the common calcination), due to the abundant formation of the crystal defects and oxygen vacancies. 展开更多
关键词 PRECURSOR MOISTURE Inert n2 ATMOSPHERE CALCInATIOnS ALUMInA MODIFIED CeZrLand mixed oxides Rare earths
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Gas metal arc welding of high nitrogen stainless steel with AreN_(2)-O_(2)ternary shielding gas 被引量:3
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作者 Zeng Liu Cheng-lei Fan +5 位作者 Zhu Ming Chao Chen Ang Liu Chun-li Yang San-bao Lin Lang-ping Wang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2021年第3期923-931,共9页
High nitrogen stainless steel with nitrogen content of 0.75%was welded by gas metal arc welding with Ar-N_(2)-O_(2)ternary shielding gas.The effect of the ternary shielding gas on the retention and improvement of nitr... High nitrogen stainless steel with nitrogen content of 0.75%was welded by gas metal arc welding with Ar-N_(2)-O_(2)ternary shielding gas.The effect of the ternary shielding gas on the retention and improvement of nitrogen content in the weld was identified.Surfacing test was conducted first to compare the ability of O_(2)and CO_(2)in prompting nitrogen dissolution.The nitrogen content of the surfacing metal with O_(2)is slightly higher than CO_(2).And then AreN_(2)-O_(2)shielding gas was applied to weld high nitrogen stainless steel.After using N_(2)-containing shielding gas,the nitrogen content of the weld was improved by 0.1 wt%.As N_(2)continued to increase,the increment of nitrogen content was not obvious,but the ferrite decreased from the top to the bottom.When the proportion of N_(2)reached 20%,a full austenitic weld was obtained and the tensile strength was improved by 8.7%.Combined with the results of surfacing test and welding test,it is concluded that the main effect of N_(2)is to inhibit the escape of nitrogen and suppress the nitrogen diffusion from bottom to the top in the molten pool. 展开更多
关键词 High nitrogen stainless steel Aren2-o2 shielding gas Action mechanism
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Investigation of the hydrate formation process in fine sediments by a binary CO2/N2 gas mixture 被引量:2
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作者 Xiaoya Zang Lihua Wan Deqing Liang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第9期2157-2163,共7页
To obtain the fundamental data of CO2/N2 gas mixture hydrate formation kinetics and CO2 separation and sequestration mechanisms,the gas hydrate formation process by a binary CO2/N2 gas mixture(50:50)in fine sediments(... To obtain the fundamental data of CO2/N2 gas mixture hydrate formation kinetics and CO2 separation and sequestration mechanisms,the gas hydrate formation process by a binary CO2/N2 gas mixture(50:50)in fine sediments(150–250μm)was investigated in a semibatch vessel at variable temperatures(273,275,and 277 K)and pressures(5.8–7.8 MPa).During the gas hydrate reaction process,the changes in the gaseous phase composition were determined by gas chromatography.The results indicate that the gas hydrate formation process of the binary CO2/N2 gas mixture in fine sediments can be reduced to two stages.Firstly,the dissolved gas containing a large amount of CO2 formed gas hydrates,and then gaseous N2 participated in the gas hydrate formation.In the second stage,all the dissolved gas was consumed.Thus,both gaseous CO2 and N2 diffused into sediment.The first stage in different experiments lasted for 5–15 h,and>60%of the gas was consumed in this period.The gas consumption rate was greater in the first stage than in the second stage.After the completion of gas hydrate formation,the CO2 content in the gas hydrate was more than that in the gas phase.This indicates that CO2 formed hydrate easily than N2 in the binary mixture.Higher operating pressures and lower temperatures increased the gas consumption rate of the binary gas mixture in gas hydrate formation. 展开更多
关键词 gas HYDRATE FORMATIOn SEDIMEnTS CO2/n2 mixTURE
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Investigation of the performance of CF3I/c-C4F8/N2 and CF3I/c-C4F8/CO2 gas mixtures from electron transport parameters 被引量:5
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作者 Ruishuang ZHONG Su ZHAO +4 位作者 Dengming XIAO Hui WANG Xiuchen JIANG Zhongmin YU Yunkun DENG 《Plasma Science and Technology》 SCIE EI CAS CSCD 2020年第5期44-51,共8页
CF3I gas mixtures have attracted considerable attention as potential environmentally-friendly alternatives to SF6 gas,owing to their excellent insulating performance.This paper attempts to study the CF3I ternary gas m... CF3I gas mixtures have attracted considerable attention as potential environmentally-friendly alternatives to SF6 gas,owing to their excellent insulating performance.This paper attempts to study the CF3I ternary gas mixtures with c-C4F8 and buffer gases N2 and CO2 by considering dielectric strength from electron transport parameters based on the Boltzmann method and synergistic effect analysis,compared with SF6 gas mixtures.The results confirm that the critical electric field strength of CF3I/c-C4F8/70%CO2 is greater than that of 30%SF6/70%CO2 when the CF3I content is greater than 17%.Moreover,a higher content of c-C4F8 decreases the sensitivity of gas mixtures to an electric field,and this phenomenon is more obvious in CF3I/c-C4F8/CO2 gas mixtures.The synergistic effects for CF3I/c-C4F8/70%N2 were most obvious when the c-C4F8 content was approximately 20%,and for CF3I/c-C4F8/70%CO2 when the c-C4F8 content was approximately 10%.On the basis of this research,CF3I/c-C4F8/70%N2 shows better insulation performance when the c-C4F8 content is in the15%–20%range.For CF3I/c-C4F8/70%CO2,when the c-C4F8 content is in the 10%–15%range,the gas mixtures have excellent performance.Hence,these gas systems might be used as alternative gas mixtures to SF6 in high-voltage equipment. 展开更多
关键词 CF3I/c-C4F8/n2 gas mixtures CF3I/c-C4F8/CO2 gas mixtures Boltzmann method electron transport parameters synergistic effect
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大气压N_2-O_2混合气纳秒脉冲表面介质阻挡放电建模仿真 被引量:11
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作者 朱益飞 贾敏 +2 位作者 崔巍 李应红 吴云 《高电压技术》 EI CAS CSCD 北大核心 2013年第7期1716-1723,共8页
大气压N2-O2混合气ns脉冲表面介质阻挡放电(SDBD)机理是等离子体气动激励与流动耦合作用机制研究的重要内容。为此,耦合等离子体化学反应动力学方程和考虑能量的等离子体漂移-扩散方程组,建立了大气压下N2-O2混合气ns脉冲放电的2维模型... 大气压N2-O2混合气ns脉冲表面介质阻挡放电(SDBD)机理是等离子体气动激励与流动耦合作用机制研究的重要内容。为此,耦合等离子体化学反应动力学方程和考虑能量的等离子体漂移-扩散方程组,建立了大气压下N2-O2混合气ns脉冲放电的2维模型。考虑15种粒子、对应的电子碰撞反应以及35个化学反应过程,得到了SDBD的伏安特性、电荷分布和能量分布。综合分析电荷及电子能量分布结果表明,高能电子撞击是产生离子的主要方式,而低能电子的累积和离子在电场驱动下的定向运动是使放电呈现非平衡的重要原因。将计算结果与实验获得的伏安特性数据、放电形态和光谱分析结果进行了比照分析,发现2者比较相符,验证了模型的可靠性。 展开更多
关键词 大气压 表面介质阻挡放电 SDBD nS脉冲 n2-o2混合气 等离子体化学 仿真模型
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煤对N_2-O_2混合气体吸附规律的试验研究 被引量:5
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作者 赵鹏涛 黄渊跃 +1 位作者 方前程 徐东方 《煤炭科学技术》 CAS 北大核心 2013年第4期57-59,共3页
为研究空气代替N2驱替煤层瓦斯的可行性,基于高压容量法,研究了煤对不同浓度配比的N2-O2混合气体的竞争吸附特性,得到试验煤样对N2-O2混合气体竞争吸附规律以及煤对混合气体中O2的吸附规律。研究表明:煤对N2-O2二元混合气体的吸附常数... 为研究空气代替N2驱替煤层瓦斯的可行性,基于高压容量法,研究了煤对不同浓度配比的N2-O2混合气体的竞争吸附特性,得到试验煤样对N2-O2混合气体竞争吸附规律以及煤对混合气体中O2的吸附规律。研究表明:煤对N2-O2二元混合气体的吸附常数介于煤对单组分的N2与O2的吸附常数之间,并且随着N2浓度的提高,吸附常数也逐渐增大,趋近于煤对单组分的N2的吸附常数;煤对混合气体中O2的吸附量处于很低水平,试验测试点范围内最大吸附量仅为1mL/g,并没有达到自燃的界限。根据试验结果可知,用空气代替N2驱替煤层瓦斯是可行的。 展开更多
关键词 竞争吸附 n2-o2混合气体 吸附规律 注气 吸附常数
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Multichannel Discharge Characteristics of Gas Switch Gap in SF_6-N_2 or SF_6-Ar Gas Mixtures Under Nanosecond Triggering Pulses
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作者 常家森 王虎 +1 位作者 张乔根 邱爱慈 《Plasma Science and Technology》 SCIE EI CAS CSCD 2011年第6期719-723,共5页
Experiments were carried out to ascertain multichannel discharge characteristics in a self-designed coaxial field-distortion gas switch filled with SFa-N2 or SF6-Ar gas mixtures of different mixing ratios. In these ex... Experiments were carried out to ascertain multichannel discharge characteristics in a self-designed coaxial field-distortion gas switch filled with SFa-N2 or SF6-Ar gas mixtures of different mixing ratios. In these experiments, the pressure varied from 0.1 MPa to 0.2 MPa, the voltage pulse peak applied to the switch was in the range from 40 kV to 78 kV, and the pulse rise time was 11 ns. The static breakdown strength of the gas switch gap in the switch was also measured. The results show that in general the average number of discharge channels for SF6-Ar or SF6-N2 gas mixture which contains less SFa is larger than that for gas mixture which contains more SF6, however, the average number of channels almost keeps constant as the gas mixing ratio varies when the pulse rise rate is high enough. The static breakdown strength of the gas switch gap decreases slightly as the content of argon or nitrogen increases. 展开更多
关键词 multichannel discharge gas dielectric strength SFB-n2 SF6-Ar mixing ratio
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Efficient CO_2/N_2 separation by mixed matrix membrane with amide functionalized porous coordination polymer filler
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作者 Qianqian Li Jingui Duan Wanqin Jin 《Chinese Chemical Letters》 SCIE CAS CSCD 2018年第6期854-856,共3页
Mixed matrix membrane used to selective removal of CO2 was considered as an efficient solution to energy and environmental sustainability. In this study, a MMM that consists of amide functionalized porous coordination... Mixed matrix membrane used to selective removal of CO2 was considered as an efficient solution to energy and environmental sustainability. In this study, a MMM that consists of amide functionalized porous coordination polymer filler(MIL-53-NH2) was successfully prepared, which sharply promotes the CO2/N2 selectivity from 44(neat polymeric membrane) to 75. Remarkably, the positive effect of amide group and nanochannel of MIL-53-NH2 filler was illustrated by decreased selectivity of the MMM with formic acid modified MIL-53-NH2 filler(MIL-53-NHCOH). 展开更多
关键词 Porous coordination polymer mixed matrix membrane CO2/n2 separation Amide group
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双歧杆菌对2′-岩藻糖基乳糖和乳糖-N-四糖的菌株特异性代谢探究
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作者 何诗微 杨波 +2 位作者 郭敏 赵建新 陈海琴 《食品与发酵工业》 北大核心 2025年第24期314-321,共8页
母乳低聚糖(human milk oligosaccharides, HMOs)是母乳中第三大固体成分,具有多种生理功能,现有研究表明其对婴儿肠道中双歧杆菌属的定植具有重要意义。前期研究聚焦于2′-岩藻糖基乳糖(2′-fucosyllactose, 2′-FL)或乳糖-N-四糖(lact... 母乳低聚糖(human milk oligosaccharides, HMOs)是母乳中第三大固体成分,具有多种生理功能,现有研究表明其对婴儿肠道中双歧杆菌属的定植具有重要意义。前期研究聚焦于2′-岩藻糖基乳糖(2′-fucosyllactose, 2′-FL)或乳糖-N-四糖(lacto-N-tetraose, LNT)等个别HMO的菌株代谢特性,该研究利用高效液相色谱质谱联用靶向代谢技术首次系统揭示5株双歧杆菌(长双歧杆菌婴儿亚种FHBSJZ50M1、长双歧杆菌长亚种CCFM752、两歧双歧杆菌FJSWX9M8、短双歧杆菌FHuNCS1M5及齿双歧杆菌FGZ15I1M1)对2′-FL、LNT及其等比例混合物的动态代谢差异。结果显示,实验所用菌株均能利用单一及混合母乳低聚糖,但其生长效率和代谢物图谱呈现显著种间差异,长双歧杆菌长亚种CCFM752能通过对2′-FL的优先级利用在双歧杆菌群落中占据主导地位。该研究揭示了双歧杆菌通过底物优先级代谢和代谢产物调控双途径塑造菌群结构,并强调了2′-FL的生态调控功能,为解析HMOs-双歧杆菌精准配伍提供了菌株级代谢证据,并为婴幼儿配方食品中益生菌-HMOs组合的精准适配奠定了理论基础。 展开更多
关键词 2′-岩藻糖基乳糖 乳糖-n-四糖 双歧杆菌 混菌培养
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H_2-O_2(N_2)混气着火过程非线性特性研究
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作者 李卓毅 张会强 《工程热物理学报》 EI CAS CSCD 北大核心 2005年第4期697-700,共4页
本文采用基元反应模拟H2-O2(N2)混合气体的着火过程,得到了不同散热和不同燃料-氧化剂初始浓度比条件下着火临界曲线。结果表明: H2/O2摩尔比相同时,不同散热条件下的着火临界曲线非常相似,可近似看成同一曲线在第二区的“延伸线”上滑... 本文采用基元反应模拟H2-O2(N2)混合气体的着火过程,得到了不同散热和不同燃料-氧化剂初始浓度比条件下着火临界曲线。结果表明: H2/O2摩尔比相同时,不同散热条件下的着火临界曲线非常相似,可近似看成同一曲线在第二区的“延伸线”上滑移。临界曲线第二区的P—T关系符合2k1=ks[Ms]。散热对着火极限的影响和着火延迟时间有密切关系,在临界曲线第二区延迟时间最小,导致散热对该区的影响最弱,从而使着火临界曲线非常相似。 展开更多
关键词 基元反应 着火临界曲线 着火 H2-o2(n2)混合气体
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用I_p作为N_2O_4-O_3硝化取代芳烃的定位判据
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作者 吕早生 吕春绪 《武汉科技大学学报》 CAS 2002年第4期352-353,360,共3页
利用前沿轨道理论及N2O4 O3硝化芳烃的机理推导出取代芳烃第一电离能与取代基定位方向之间关系,用第一电离能IP的大小判断N2O4 O3硝化各种取代芳烃过程中NO2基团所取代的位置,提出了判断取代芳烃中取代基是对位定位基还是间位定位基的判... 利用前沿轨道理论及N2O4 O3硝化芳烃的机理推导出取代芳烃第一电离能与取代基定位方向之间关系,用第一电离能IP的大小判断N2O4 O3硝化各种取代芳烃过程中NO2基团所取代的位置,提出了判断取代芳烃中取代基是对位定位基还是间位定位基的判据,此判据与实验结果相一致。 展开更多
关键词 IP n2O4-o3硝化取代芳烃 硝化反应 定位判据 第一电离能 取代基 前沿轨道理论
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N_2O_4-O_3硝化取代芳烃时取代基上的P轨道的邻位协助作用
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作者 吕早生 汪弋 《武汉科技大学学报》 CAS 2002年第3期245-246,273,共3页
对N2 O4 O3 硝化取代芳烃进行广泛的研究 ,发现其产物的异构体分布与传统的混酸硝化产物的异构体分布有很大差别 ,并对造成这种差别的原因进行了分析。分析表明 ,取代基上的P轨道的邻位协助作用是主要因素 。
关键词 n2O4-o3 取代芳烃 取代基 P轨道 邻位协助作用 硝化反应 四氧化二氮 异构体分布
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Na改性ZSM-5吸附剂对C_(4)F_(7)N/CO_(2)混合气体及其分解产物的吸附特性
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作者 朱峰 赵跃 +1 位作者 马凤翔 刘伟 《高电压技术》 北大核心 2025年第12期5878-5888,共11页
C_(4)F_(7)N/CO_(2)混合气体作为替代SF6最有潜力的新型绝缘气体,具有广阔的应用前景,但其在长期运行过程中可能会因为过热或放电等发生分解,影响设备的安全运行。为提高绝缘设备的运行水平,文中首先搭建过热分解吸附实验平台,采用气相... C_(4)F_(7)N/CO_(2)混合气体作为替代SF6最有潜力的新型绝缘气体,具有广阔的应用前景,但其在长期运行过程中可能会因为过热或放电等发生分解,影响设备的安全运行。为提高绝缘设备的运行水平,文中首先搭建过热分解吸附实验平台,采用气相色谱-质谱联用仪、傅里叶红外光谱仪对混合气体及其分解组分的吸附率进行检测;其次结合Multiwfn、GaussView 6.0.16软件阐明吸附机理;最终利用分子动力学模拟开展ZSM-5分子筛Na改性与全硅模型吸附对比研究。研究发现:ZSM-5分子筛改性前对CO_(2)、C_(4)F_(7)N、C_(2)F_(5)CN、C_(3)F_(6)、C_(3)F_(8)、CF_(3)CN、CF_(4)的吸附率均不高,经Na改性后对C_(3)F_(8)和CF_(3)CN两种气体的吸附能力增强,而对CO_(2)的吸附能力几乎未受影响,这一特性有利于C_(4)F_(7)N/CO_(2)混合气体的分离,也为后续新型吸附剂的研发提供理论支撑。 展开更多
关键词 热分解产物 分子动力学模拟 ZSM-5分子筛 na改性 C_(4)F_(7)n/CO_(2)混合气体
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基于126 kV共箱型GIL的空气和C_(4)F_(7)N/CO_(2)混合气体温升特性研究
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作者 李端姣 孙文星 +1 位作者 陈宇慧 胡晓光 《绝缘材料》 北大核心 2025年第7期143-150,共8页
气体绝缘输电线路(GIL)的温升特性决定了其通流容量,为掌握全氟异丁腈(C_(4)F_(7)N)混合气体和干燥空气这两类典型环保绝缘气体的温升特性,对126 kV三相共箱型气体绝缘输电线路的温升过程进行仿真,根据仿真结果建立温升试验平台,开展了... 气体绝缘输电线路(GIL)的温升特性决定了其通流容量,为掌握全氟异丁腈(C_(4)F_(7)N)混合气体和干燥空气这两类典型环保绝缘气体的温升特性,对126 kV三相共箱型气体绝缘输电线路的温升过程进行仿真,根据仿真结果建立温升试验平台,开展了不同气体介质、不同通流等条件下的温升试验。结果表明:在相同通流条件下,C4F7N/CO_(2)混合气体与干燥空气在典型应用参数下的温升接近,但均高于SF6气体的温升;当通流为3 150 A时,充入C_(4)F_(7)N/CO_(2)混合气体与干燥空气均可满足设备温升不超过75 K的要求,但当通流为3 465 A时,充入C4F7N/CO_(2)混合气体与干燥空气均无法满足设备温升要求;同时还发现,分别充入3种气体时B相温升均高于A、C相,符合仿真结果和热对流过程,说明在126 kV三相共箱型GIL的温升设计中需要重点考虑B相导体的最高温升。 展开更多
关键词 环保型气体绝缘输电线路 环保绝缘气体 温升特性 C_(4)F_(7)n/CO_(2)混合气体 干燥空气
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C_(4)F_(7)N/CO_(2)混合绝缘气体紫外光谱特性及检测方法研究
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作者 陈经纬 贝逸群 +2 位作者 朱立铭 张嵩 李博 《科技资讯》 2025年第11期69-71,共3页
随着人们环保意识的不断提升和国家可持续发展的迫切需求,近年来,对环保绝缘气体的研究和应用日益受到关注。C_(4)F_(7)N/CO_(2)作为传统SF_(6)气体的一种有前景的替代品,因其优异的绝缘特性和较低的环境影响而备受瞩目。系统地分析了C_... 随着人们环保意识的不断提升和国家可持续发展的迫切需求,近年来,对环保绝缘气体的研究和应用日益受到关注。C_(4)F_(7)N/CO_(2)作为传统SF_(6)气体的一种有前景的替代品,因其优异的绝缘特性和较低的环境影响而备受瞩目。系统地分析了C_(4)F_(7)N/CO_(2)气体混合物的紫外光谱特性,并提出了一种基于紫外光谱的新型检测方法。实验结果表明,紫外光谱技术检测C_(4)F_(7)N/CO_(2)气体混合物是可行且有效的,为环保绝缘气体在电力系统中的开发和应用提供了宝贵的参考。 展开更多
关键词 C_(4)F_(7)n/CO_(2)混合气体 紫外光谱 光谱特性 混合比
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Enhanced gas separation performance of mixed matrix hollow fiber membranes containing post-functionalized S-MIL-53 被引量:6
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作者 Haitao Zhu Xingming Jie +3 位作者 Lina Wang Guodong Kang Dandan Liu Yiming Cao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2018年第3期781-790,共10页
Mixed matrix hollow fiber membranes(MMHFMs)filled with metal-organic frameworks(MOFs)have great potential for energy-efficient gas separation processes,but the major hurdle is polymer/MOFs interfacial defects and ... Mixed matrix hollow fiber membranes(MMHFMs)filled with metal-organic frameworks(MOFs)have great potential for energy-efficient gas separation processes,but the major hurdle is polymer/MOFs interfacial defects and membrane plasticization.Herein,lab-synthesized MIL-53 was post-functionalized by aminosilane grafting and subsequently incorporated into Ultem-1000 polymer matrix to fabricate high performance MMHFMs.SEM,DLS,XRD and TGA were performed to characterize silane-modified MIL-53(S-MIL-53)and prepared MMHFMs.Moreover,the effect of MOFs loading was systematically investigated first;then gas separation performance of MMHFMs for pure and mixed gas was evaluated under different pressures.MMHFMs containing post-functionalized S-MIL-53 achieved remarkable gas permeation properties which was better than model predictions.Compared to pure HFMs,CO2permeance of MMHFM loaded with 15%S-MIL-53 increased by 157%accompanying with 40%increase for CO2/N2selectivity,which outperformed the MMHFM filled with naked MIL-53.The pure and mixed gas permeation measurements with elevated feed pressure indicated that incorporation of S-MIL-53 also increased the resistance against CO2plasticization.This work reveals that post-modified MOFs embedded in MMHFMs facilitate the improvement of gas separation performance and suppression of membrane plasticization. 展开更多
关键词 Post-functionalized S-MIL-53 mixed matrix hollow fiber membranes CO2 permeance Plasticization gas separation
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