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期刊论文 8

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四极杆 1

生物标志物 1

碰撞诱导解离 1

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线形离子阱 1

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Determination of the dissociation constants of polyepoxysuccinic acid

ZHANG Lihua, ZHU Zhiliang, QIU Yanling, ZHANG Ronghua, ZHAO Jianfu

《环境科学与工程前沿（英文）》 2008年 第2卷 第4期   页码 505-508 doi: 10.1007/s11783-008-0077-x

摘要： The dissociation constants of polyepoxysuccinic acid (PESA) were investigated in this study. Based on the potentiometric titration and the BEST program, the dissociation constants of PESA were determined. Considering the complexity of the dissociation of PESA in aqueous solution, several models were constructed to simulate the dissociation process of PESA. By comparison, the dissociation constants of PESA were obtained with model 4. The species distribution of PESA in aqueous solution as a function of pH was also presented according to the experimental and calculation results. It showed that the HL model with five basic structure units to describe the dissociation of PESA was reasonable, and the relevant constants had less error and better matching between the experimental and calculation data. The corresponding values of p were 4.68 and 4.92, respectively, for HL at 35°C with ionic strength of 0.1 mol/L.

关键词： function     comparison     relevant     corresponding     dissociation    

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Peroxyacetyl nitrate measurements by thermal dissociation–chemical ionization mass spectrometry in an

Xinfeng Wang, Tao Wang, Likun Xue, Wei Nie, Zheng Xu, Steven C. N. Poon, Wenxing Wang

《环境科学与工程前沿（英文）》 2017年 第11卷 第4期 doi: 10.1007/s11783-017-0925-7

摘要： Peroxyacetyl nitrate (PAN) is an important indicator of photochemical smog and has adverse effects on human health and vegetation growth. A rapid and highly selective technique of thermal dissociation–chemical ionization mass spectrometry (TD-CIMS) was recently developed to measure the abundance of PAN in real time; however, it may be subject to artifact in the presence of nitric oxide (NO). In this study, we tested the interference of the PAN signal induced by NO, evaluated the performance of TD-CIMS in an urban environment, and investigated the concentration and formation of PAN in urban Hong Kong. NO caused a significant underestimation of the PAN signal in TD-CIMS, with the underestimation increasing sharply with NO concentration and decreasing slightly with PAN abundance. A formula was derived to link the loss of PAN signal with the concentrations of NO and PAN, which can be used for data correction in PAN measurements. The corrected PAN data from TD-CIMS were consistent with those from the commonly used gas chromatography with electron capture detection, which confirms the utility of TD-CIMS in an urban environment in which NO is abundant. In autumn of 2010, the hourly average PAN mixing ratio varied from 0.06 ppbv to 5.17 ppbv, indicating the occurrence of photochemical pollution in urban Hong Kong. The formation efficiency of PAN during pollution episodes was as high as 3.9 to 5.9 ppbv per 100 ppbv ozone. PAN levels showed a near-linear increase with NO concentration, suggesting a control policy of NO reduction for PAN pollution.

关键词： TD-CIMS     Peroxyacetyl nitrate     Interference     Photochemical pollution     Formation efficiency    

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A mini review on chemical fixation of CO 2 : Absorption and catalytic conversion into cyclic carbonates

Weili DAI, Chaktong AU, Shenglian LUO, Shuangfeng YIN,

《化学科学与工程前沿（英文）》 2010年 第4卷 第2期   页码 163-171 doi: 10.1007/s11705-009-0235-0

摘要： In this article, we present our research results on chemical fixation of CO using organobismuth compounds. We fabricated bismuth biphenoate complex, Zn-Mg-Al composite oxides, and SBA-15 or Al-SBA-15 immobilized hydroxyl ionic liquid for CO cycloaddition onto epoxides. The hypervalent bismuth compounds show good ability for association and dissociation with CO. The bismuth biphenolate complexes are catalytically effective for the cycloaddition reaction. The heterogeneous catalysts, viz. Zn-Mg-Al oxides and SBA-15 or Al-SBA-15 immobilized ionic liquid, are efficient for the synthesis of cyclic carbonate from CO and epoxide. It is found that the presence of a trace amount of water can improve the catalytic activity of the immobilized ionic liquid.

关键词： SBA-15     CO cycloaddition     Al-SBA-15 immobilized     CO     dissociation    

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Mechanism of dichloromethane disproportionation over mesoporous TiO

Yuzhou Deng, Shengpan Peng, Haidi Liu, Shuangde Li, Yunfa Chen

《环境科学与工程前沿（英文）》 2019年 第13卷 第2期 doi: 10.1007/s11783-019-1113-8

摘要：

• Mechanism of DCM disproportionation over mesoporous TiO2 was studied.

• DCM was completely eliminated at 350℃ under 1 vol.% humidity.

• Anatase (001) was the key for disproportionation.

• A competitive oxidation route co-existed with disproportionation.

• Disproportionation was favored at low temperature.

关键词： Dichloromethane     Disproportionation     Mechanism     Anatase (001)     Water dissociation    

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Latest progress in numerical simulations on multiphase flow and thermodynamics in production of natural gas from gas hydrate reservoir

Lin ZUO, Lixia SUN, Changfu YOU

《能源前沿（英文）》 2009年 第3卷 第2期   页码 152-159 doi: 10.1007/s11708-009-0017-x

摘要： Natural gas hydrates are promising potential alternative energy resources. Some studies on the multiphase flow and thermodynamics have been conducted to investigate the feasibility of gas production from hydrate dissociation. The methods for natural gas production are analyzed and several models describing the dissociation process are listed and compared. Two prevailing models, one for depressurization and the other for thermal stimulation, are discussed in detail. A comprehensive numerical method considering the multiphase flow and thermodynamics of gas production from various hydrate-bearing reservoirs is required to better understand the dissociation process of natural gas hydrate, which would be of great benefit to its future exploration and exploitation.

关键词： numerical simulation     natural gas hydrate     dissociation     thermodynamics     multiphase flow    

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A density functional theory study of methane activation on MgO supported NiM cluster: role of M on C–H activation

《化学科学与工程前沿（英文）》 2022年 第16卷 第10期   页码 1485-1492 doi: 10.1007/s11705-022-2169-8

摘要： Methane activation is a pivotal step in the application of natural gas converting into high-value added chemicals via methane steam/dry reforming reactions. Ni element was found to be the most widely used catalyst. In present work, methane activation on MgO supported Ni–M (M = Fe, Co, Cu, Pd, Pt) cluster was explored through detailed density functional theory calculations, compared to pure Ni cluster. CH4 adsorption on Cu promoted Ni cluster requires overcoming an energy of 0.07 eV, indicating that it is slightly endothermic and unfavored to occur, while the adsorption energies of other promoters M (M = Fe, Co, Pd and Pt) are all higher than that of pure Ni cluster. The role of M on the first C–H bond cleavage of CH4 was investigated. Doping elements of the same period in Ni cluster, such as Fe, Co and Cu, for C–H bond activation follows the trend of the decrease of metal atom radius. As a result, Ni–Fe shows the best ability for C–H bond cleavage. In addition, doping the elements of the same family, like Pd and Pt, for CH4 activation is according to the increase of metal atom radius. Consequently, C–H bond activation demands a lower energy barrier on Ni–Pt cluster. To illustrate the adsorptive dissociation behaviors of CH4 at different Ni–M clusters, the Mulliken atomic charge was analyzed. In general, the electron gain of CH4 binding at different Ni–M clusters follows the sequence of Ni–Cu (–0.02 e) < Ni (–0.04 e) < Ni–Pd (–0.08 e) < Ni–Pt (–0.09 e) < Ni–Co (–0.10 e) < Ni–Fe (–0.12 e), and the binding strength between catalysts and CH 4 raises with the CH4 electron gain increasing. This work provides insights into understanding the role of promoter metal M on thermal-catalytic activation of CH4 over Ni/MgO catalysts, and is useful to interpret the reaction at an atomic scale.

关键词： CH4 dissociation     Ni–M     C–H bond activation     charge transfer    

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Simultaneous removal of trihalomethanes by bimetallic Ag/Zn: kinetics study

Ahmed H A DABWAN, Satoshi KANECO, Hideyuki KATSUMATA, Kiyoyuki EGUSA, Tohru SUZUKI, Kiyohisa OHTA,

《化学科学与工程前沿（英文）》 2010年 第4卷 第3期   页码 322-327 doi: 10.1007/s11705-009-0261-y

摘要： In the present work, bimetallic silver/zinc was applied into the degradation of trihalomethanes, THMs: CHCl, CHBrCl, CHBrCl, and CHBr. The kinetics reaction rates and removal efficiencies of the THM compound mixtures, in the aqueous solutions, were investigated. Batch experiments were conducted under mild conditions, ambient temperature, and pressure. The primary degradation reaction followed a pseudo-first-order kinetic law. The first-order rate constants and the degradation efficiencies followed the decreasing order of CHBr>CHBrCl>CHBrCl>CHCl. The bond dissociation energy and hydrophilic/hydrophobic characteristics of the THM compounds may become the most important parameters affecting the degradation kinetics and efficiency by bimetallic Ag/Zn.

关键词： reaction     first-order     dissociation     degradation reaction     aqueous    

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四极杆-线形离子阱串联质谱系统及临床生物标志物分析 Article

方向, 谢洁, 楚士颖, 江游, 安育廷, 李畅, 龚晓云, 翟睿, 黄泽建, 裘春玲, 戴新华

《工程（英文）》 2022年 第16卷 第9期   页码 56-64 doi: 10.1016/j.eng.2020.10.021

摘要： 碰撞诱导解离（collision-induced dissociation, CID）由共振激发，其无量纲马修参数q值为0.40。激发50 ms，CID效率达64%。

关键词： 线形离子阱     四极杆     空间电荷效应     碰撞诱导解离     生物标志物    

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标题 作者 时间 类型 操作

Determination of the dissociation constants of polyepoxysuccinic acid

ZHANG Lihua, ZHU Zhiliang, QIU Yanling, ZHANG Ronghua, ZHAO Jianfu

期刊论文

Peroxyacetyl nitrate measurements by thermal dissociation–chemical ionization mass spectrometry in an

Xinfeng Wang, Tao Wang, Likun Xue, Wei Nie, Zheng Xu, Steven C. N. Poon, Wenxing Wang

期刊论文

A mini review on chemical fixation of CO 2 : Absorption and catalytic conversion into cyclic carbonates

Weili DAI, Chaktong AU, Shenglian LUO, Shuangfeng YIN,

期刊论文

Mechanism of dichloromethane disproportionation over mesoporous TiO

Yuzhou Deng, Shengpan Peng, Haidi Liu, Shuangde Li, Yunfa Chen

期刊论文

Latest progress in numerical simulations on multiphase flow and thermodynamics in production of natural gas from gas hydrate reservoir

Lin ZUO, Lixia SUN, Changfu YOU

期刊论文

A density functional theory study of methane activation on MgO supported NiM cluster: role of M on C–H activation

期刊论文

Simultaneous removal of trihalomethanes by bimetallic Ag/Zn: kinetics study

Ahmed H A DABWAN, Satoshi KANECO, Hideyuki KATSUMATA, Kiyoyuki EGUSA, Tohru SUZUKI, Kiyohisa OHTA,

期刊论文

四极杆-线形离子阱串联质谱系统及临床生物标志物分析

方向, 谢洁, 楚士颖, 江游, 安育廷, 李畅, 龚晓云, 翟睿, 黄泽建, 裘春玲, 戴新华

期刊论文