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期刊论文 36

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碳酸盐岩 3

动力学 2

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二苯甲酮 1

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Direct synthesis of diphenyl carbonate over heterogeneous catalyst: effects of structure of substituted

WU Guangwen, JIN Fang, WU Yuxin, ZHANG Guangxu, LI Dinghuo, WANG Cunwen, MA Peisheng

《化学科学与工程前沿（英文）》 2007年 第1卷 第1期   页码 59-64 doi: 10.1007/s11705-007-0012-x

摘要： The perovskite-type compound LaMnO was substituted for the part of La in position A and for the part of Mn in position B by citrate method. The phases were detected by X-ray diffraction. Powder morphologies were scanned by scanning electron microscopy. The valence of atoms was determined by X-ray photoelectron spectroscopy. It was found that the perovskite can form crystal defect and increase the proportion of high valence B element by doping. Active component Pd was loaded on various perovskite supports for synthesis of diphenyl carbonate. The results showed that the activities of catalysts in which supports have crystal defect by substitution were higher. It can be concluded that perovskite with defect structure by doping could lead to the formation of oxygen vacancy where the lattice oxygen became exchangeable with the oxygen gas. Also, this improved the redox process of the carrier by transferring electrons and activities of catalysts.

关键词： photoelectron spectroscopy     diphenyl carbonate     proportion     diffraction     perovskite    

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Removing polybrominated diphenyl ethers in pure water using Fe/Pd bimetallic nanoparticles

Min ZHANG,Jian LU,Zhencheng XU,Yiliang HE,Bo ZHANG,Song JIN,Brian BOMAN

《环境科学与工程前沿（英文）》 2015年 第9卷 第5期   页码 832-839 doi: 10.1007/s11783-015-0778-x

摘要： Polybrominated diphenyl ethers (PBDEs) have been widely used as fire-retardants. Due to their high production volume, widespread usage, and environmental persistence, PBDEs have become ubiquitous contaminants in various environments.Nanoscale zero-valent iron (ZVI) is an effective reductant for many halogenated organic compounds. To enhance the degradation efficiency, ZVI/Palladium bimetallic nanoparticles (nZVI/Pd) were synthesized in this study to degrade decabromodiphenyl ether (BDE209) in water. Approximately 90% of BDE209 was rapidly removed by nZVI/Pd within 80 min, whereas about 25% of BDE209 was removed by nZVI. Degradation of BDE209 by nZVI/Pd fits pseudo-first-order kinetics. An increase in pH led to sharply decrease the rate of BDE209 degradation. The degradation rate constant in the treatment with initial pH at 9.0 was more than 6.8 × higher than that under pH 5.0. The degradation intermediates of BDE209 by nZVI/Pd were identified and the degradation pathways were hypothesized. Results from this study suggest that nZVI/Pd may be an effective tool for treating polybrominated diphenyl ethers (PBDEs) in water.

关键词： degradation     bimetallic nanoparticles     nanoscale zero-valent iron     polybrominated diphenyl ethers    

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Photocatalytic degradation of polybrominated diphenyl ethers in pure water system

Min ZHANG,Jian LU,Yiliang HE,P Chris WILSON

《环境科学与工程前沿（英文）》 2016年 第10卷 第2期   页码 229-235 doi: 10.1007/s11783-014-0762-x

摘要： Due to the low water solubility of polybrominated diphenyl ethers, organic solvent is usually added into the oxidation system to enhance the removal efficiency. In this study the photocatalytic degradation of decabromodiphenyl ether (BDE209), a type of polybrominated diphenyl ether used throughout the world, in pure water without the addition of organic solvent was investigated. In the pure water system, BDE209 was not dissolved but dispersed as nano-scale particles with a mean diameter of 166 nm. Most of BDE209 (>98%) were removed within 4 h and the final debromination ratio was greater than 80%. Although the addition of organic solvent (tetrahydrofuran, THF) could lead to a relatively high BDE209 degradation rate, the final debromination ratio (<50%) was much lower than that in pure water system. Major oxidation intermediates of tetrahydrofuran, including tetrahydro-2-furanol and γ-butyrolactone, were detected indicating the engagement of THF in the BDE209 degradation process. The photocatalytic degradation of BDE209 in the pure water system followed first-order kinetics. The BDE209 degradation rate constant increased from 0.0011 to 0.0023 min as the pH increased from 3 to 9.

关键词： polybrominated diphenyl ethers     photocatalytic degradation     solvent    

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Polyethylene glycol-supported ionic liquid as a highly efficient catalyst for the synthesis of propylene carbonate

Rui YAO, Hua WANG, Jinyu HAN

《化学科学与工程前沿（英文）》 2012年 第6卷 第3期   页码 239-245 doi: 10.1007/s11705-012-1297-y

摘要： The coupling reaction of propylene and CO to form propylene carbonate (PC) was promoted by an ionic liquid (IL) covalently bound to polyethylene glycol (PEG). The supported ionic liquid, which has both acidic and basic components, proved to be an active catalyst for PC synthesis under mild conditions. The effects of different cations and anions, reaction temperature, CO pressure, and reaction time were investigated. It was demonstrated that the acid group in the catalyst plays an important role in the reaction. With this system, a high PC yield (95%) was achieved under mild conditions (3.0 MPa, 120°C and 4 h) without a co-solvent. In addition, the catalyst was readily recovered and reused. Based on the experimental results, a plausible mechanism for the catalyst was proposed.

关键词： ionic liquid     PEG-supported ionic liquid     carbon dioxide     propylene carbonate    

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Synthesis and fluorescence behavior of 2,5-diphenyl-1,3,4-oxadiazole-containing bismaleimides and bissuccinimides

Xin ZHANG, Zichen LI

《化学科学与工程前沿（英文）》 2013年 第7卷 第4期   页码 381-387 doi: 10.1007/s11705-013-1359-9

摘要： Bismaleimides bearing 2,5-diphenyl-1,3,4-oxadiazole chromophores at , , position and corresponding saturated bissuccinimides were synthesized. Several synthetic strategies for these bismaleimides were discussed in detail. Almost no or very weak fluorescence was observed for these bismaleimides, however, the bissuccinimides show a strong fluorescence. The effect of molecular geometry on optical behavior and fluorescence quenching mechanism were investigated by UV-vis absorption and fluorescence emission spectroscopy. The electron coupling of ground state of -bismaleimide is stronger than those of - and -bismaleimides. -Bissuccinimide displays increasing fluorescence quantum yields with red shifts of 22–24 nm, compared to -bissuccinimide. Polymerizable C=C bonds play a key role in the intramolecular fluorescence quenching.

关键词： fluorescence     bismaleimide     oxadiazole     succinimide    

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Effect of wastewater composition on the calcium carbonate precipitation in upflow anaerobic sludge blanket

Shucheng YANG, Yanling HE, Charles CHOU, Pengxiang ZHANG, Dongqi WANG, Yonghong LIU,

《环境科学与工程前沿（英文）》 2010年 第4卷 第2期   页码 142-149 doi: 10.1007/s11783-010-0026-3

摘要： Calcium carbonate often precipitates in anaerobic reactors treating wastewater with high calcium content. The aim of this paper is to study the effect of wastewater composition on calcium carbonate precipitation in upflow anaerobic sludge blanket (UASB) reactors. Two laboratory-scale UASB reactors were operated with calcium-containing influents using acetate and carbohydrate as substrate, respectively. There was an obvious accumulation of inorganic precipitate observed in the biogranules. Observations via scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS) showed that the acclimated biogranules in the two reactors differed in microstructure. Calcium carbonate was found to have precipitated on the surface of acetate-degrading biogranules, but precipitated at the core of the carbohydrate-degrading biogranules. The results indicated that substrates had significant influence on the location of calcium carbonate precipitation in anaerobic granular sludge, which was expected due to the different methanogens distribution and pH gradient within the granular sludge degrading various substrates. Moreover, the location of calcium carbonate precipitation substantially affected the specific methanogenic activity (SMA) of the granular sludge. The SMA of the acetate-degrading biogranules dropped from 1.96 gCOD·gVSS·d to 0.61 gCOD·gVSS·d after 180-d of operation in the reactor. However, the SMA of the carbohydrate-degrading biogranules was not adversely affected by calcium carbonate precipitation.

关键词： calcium carbonate     precipitation     anaerobic granular sludge     wastewater composition     microstructure     upflow anaerobic sludge blanket (UASB)    

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85 nmUV降解水中二苯甲酮和孔雀石绿的动力学研究

闻瑞梅,葛伟伟

《中国工程科学》 2007年 第9卷 第9期   页码 40-46

摘要：

研究了185 nmUV降解水中 二苯甲酮和孔雀石绿的动力学，主要 包括185 nmUV降解水中有机物的动力 学分析，反应速率常数的理论分析， 各种因素如温度、浓度、pH值以及流 速等影响反应速率常数的因素分析， 并建立化学反应动力学方程；讨论185 nmUV降解水中的二苯甲酮和孔雀石绿的 动力学规律；从理论和实验讨论185 nmUV 降解水中的二苯甲酮和孔雀石绿是符合准 一级动力学规律。

关键词： 水     185 nmUV     二苯甲酮     孔雀石绿     动力学    

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Novel eco-efficient reactive distillation process for dimethyl carbonate production by indirect alcoholysis

Iulian Patraşcu, Costin S. Bîldea, Anton A. Kiss

《化学科学与工程前沿（英文）》 2022年 第16卷 第2期   页码 316-331 doi: 10.1007/s11705-021-2047-9

摘要： Dimethyl carbonate is an eco-friendly essential chemical that can be sustainably produced from CO , which is available from carbon capture activities or can even be captured from the air. The rapid increase in dimethyl carbonate demand is driven by the fast growth of polycarbonates, solvent, pharmaceutical, and lithium-ion battery industries. Dimethyl carbonate can be produced from CO through various chemical pathways, but the most convenient route reported is the indirect alcoholysis of urea. Previous research used techniques such as heat integration and reactive distillation to reduce the energy use and costs, but the use of an excess of methanol in the trans-esterification step led to an energy intensive extractive distillation required to break the dimethyl carbonate-methanol azeotrope. This work shows that the production of dimethyl carbonate by indirect alcoholysis of urea can be improved by using an excess of propylene carbonate (instead of an excess of methanol), a neat feat that we showed it requires only 2.64 kW·h·kg dimethyl carbonate in a reaction-separation-recycle process, and a reactive distillation column that effectively replaces two conventional distillation columns and the reactor for dimethyl carbonate synthesis. Therefore, less equipment is required, the methanol-dimethyl carbonate azeotrope does not need to be recycled, and the overall savings are higher. Moreover, we propose the use of a reactive distillation column in a heat integrated process to obtain high purity dimethyl carbonate (>99.8 wt-%). The energy requirement is reduced by heat integration to just 1.25 kW·h·kg dimethyl carbonate, which is about 52% lower than the reaction-separation-recycle process. To benefit from the energy savings, the dynamics and control of the process are provided for ±10% changes in the nominal rate of 32 ktpy dimethyl carbonate, and for uncertainties in reaction kinetics.

关键词： dimethyl carbonate     reactive distillation     process design     plantwide control    

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地下水碳酸平衡检查系统

刘建刚,郑克勋,傅伟宁,吴顺华

《中国工程科学》 2003年 第5卷 第9期   页码 61-64

摘要：

文章主要研究地下水在不同温度和CO2分压条件下碳酸三种存在形式与pH值的关系，以便更有效地对地下水水质资料进行可靠性检查。分析认为HCO3-出现峰值的分界pH0值，纯水在CO2分压1～105Pa，温度0～30℃时的变化范围为7.92～8.60，碳酸盐岩地下水的变化范围为8.28～8.57。pH0值随温度的升高而降低。石灰岩和白云岩的pH0十分接近，碳酸盐岩地区的平衡特性将取决于方解石成分。

关键词： 碳酸盐岩     地下水     碳酸平衡     pH值    

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Multi-objective optimization of molten carbonate fuel cell system for reducing CO

Ramin ROSHANDEL,Majid ASTANEH,Farzin GOLZAR

《能源前沿（英文）》 2015年 第9卷 第1期   页码 106-114 doi: 10.1007/s11708-014-0341-7

摘要： The aim of this paper is to investigate the implementation of a molten carbonate fuel cell (MCFC) as a CO separator. By applying multi-objective optimization (MOO) using the genetic algorithm, the optimal values of operating load and the corresponding values of objective functions are obtained. Objective functions are minimization of the cost of electricity (COE) and minimization of CO emission rate. CO tax that is accounted as the pollution-related cost, transforming the environmental objective to the cost function. The results show that the MCFC stack which is fed by the syngas and gas turbine exhaust, not only reduces CO emission rate, but also produces electricity and reduces environmental cost of the system.

关键词： molten carbonate fuel cell (MCFC)     multi-objective optimization (MOO)     Pareto curve     genetic algorithm     CO2 separation    

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Legacies and health risks of heavy metals, polybrominated diphenyl ethers, and polychlorinated dibenzo-dioxins

《环境科学与工程前沿（英文）》 2023年 第17卷 第7期 doi: 10.1007/s11783-023-1679-z

摘要：

● Heavy metals and organic toxins may persist in legacy sites for a long time.

关键词： E-waste     Human health risk     Organ risk     Heavy metal toxicity     PBDE     PCDD/F    

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Effect of potassium carbonate on catalytic synthesis of calcium carbide at moderate temperature

Dejun SHI, Ke QIAO, Zifeng YAN

《化学科学与工程前沿（英文）》 2011年 第5卷 第3期   页码 372-375 doi: 10.1007/s11705-010-0570-1

摘要： Calcium carbide was successfully synthesized by carbothermal reduction of lime with coke at 1973 K for 1.5 h. The effect of potassium carbonate as additive on the composition and morphology of the product was investigated using X-ray diffraction and scanning electron microscope. Addition of potassium carbonate increased the yield of calcium carbide. The sample in the presence of potassium carbonate generated acetylene gas of 168.3 L/kg, which was 10% higher than that in the absence of potassium carbonate. This result confirmed the catalytic effect of potassium carbonate on the synthesis of calcium carbide. A possible mechanism of the above effects was that the additive, which was melted at the reduction temperature, dissolved CaO and so promoted the contact between CaO and carbon, which was essential for the solid-solid reaction to form calcium carbide.

关键词： calcium carbide     synthesis     catalysis    

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Influence of crystalline phase of Li-Al-O oxides on the activity of Wacker-type catalysts in dimethyl carbonate

Yadong GE, Yuanyuan DONG, Shengping WANG, Yujun ZHAO, Jing LV, Xinbin MA

《化学科学与工程前沿（英文）》 2012年 第6卷 第4期   页码 415-422 doi: 10.1007/s11705-012-1214-4

摘要： The catalysts supported on LiAl O (spinel) for vapor phase synthesis of dimethyl carbonate (DMC) from methyl nitrite (MN) have been studied. Their catalytic activities on supports prepared by different methods were evaluated in a continuous reactor. The samples were characterized by powder X-ray diffraction, N adsorption-desorption isotherms, fourier transform infrared spectroscopy and temperature-programmed reduction of H . Li/Al molar ratio and calcination temperature greatly influence the structure of crystalline phase of Li-Al-O oxides. Desirable LiAl O (spinel) was formed at 800°C, while LiAl O (primitive cube) formed at 900°C is undesirable for the reaction. A high Li/Al molar ratio, which was related with LiAlO , also slowed the reaction rate. The electron transfer ability and the interaction with active component are the important properties of the spinel-based supports. The CuCl -PdCl /LiAl O (spinel) with better electron transfer ability and low Pd reduction temperature exhibited a better catalytic ability.

关键词： Wacker-type catalyst     dimethyl carbonate     methyl nitrite     spinel    

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碱硅酸反应与碱碳酸盐反应

唐明述

《中国工程科学》 2000年 第2卷 第1期   页码 34-40

摘要：

碱集料反应（AAR）可分为两类，即碱硅酸反应（ASR）与碱碳酸盐反应（ACR）。二者的共同点是与碱发生的化学反应可导致混凝土中集料的体积增大，从而可能使混凝土甚至整个建筑物或构筑物发生膨胀开裂。文章着重从膨胀过程和机理以及岩石的结构特征探讨二者的特性与差异。ASR类型岩石具有碱活性的前提条件是较低的二氧化硅结晶完整度。只有隐晶质、微晶质、玻璃质或发生过应变的二氧化硅才会具有较高的化学活性，导致混凝土破坏。通过系统研究证实，对碱碳酸盐反应，虽然结晶的完整程度以及白云石（CaCO3·MgCO3）分子式中Ca/Mg比也将影响其与碱反应的速率，但起决定作用的是白云石晶体的尺寸及其在岩石中的分布状态和被基质包围的紧密程度。从微观结构得出的这些特征将有助于加深对碱集料反应膨胀机理的认识。文中还介绍了形成活性白云石的地质环境和碱硅酸反应与碱碳酸盐反应的区分方法。

关键词： 碱     集料     硅酸     碳酸盐     混凝土开裂     机理    

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Direct synthesis of dimethyl carbonate over rare earth oxide supported catalyst

JIANG Qi, CHENG Jiye, GAO Zhiqin

《化学科学与工程前沿（英文）》 2007年 第1卷 第3期   页码 300-303 doi: 10.1007/s11705-007-0055-z

摘要： Solid base catalysts for the direct synthesis of dimethyl carbonate (DMC) from carbon dioxide, methanol, and propylene oxide were prepared by loading KCl and KCO on the surface of LaO, YO, CeO and NdO. The catalysts were characterized by thermogravimetric analysis (TGA) and X-ray diffraction (XRD) techniques. The catalytic activities were efficiently influenced by the preparation conditions. The optimal loading amount of KCO is 17.6% (mass) for KCl-KCO/YO and 22.2% for other catalysts. Supports affected the activity of catalyst. KCl-KCO/NdO exhibited the highest activity. The activity of KCl-KCO/YO increased with the increase of calcination temperature in the range of 800ºC–900ºC. The formation of KYO, YOCl or YO species probably promoted the catalysts.

关键词： thermogravimetric analysis     increase     KCl-KCO/NdO     catalytic     KCl-KCO/YO    

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标题 作者 时间 类型 操作

Direct synthesis of diphenyl carbonate over heterogeneous catalyst: effects of structure of substituted

WU Guangwen, JIN Fang, WU Yuxin, ZHANG Guangxu, LI Dinghuo, WANG Cunwen, MA Peisheng

期刊论文

Removing polybrominated diphenyl ethers in pure water using Fe/Pd bimetallic nanoparticles

Min ZHANG,Jian LU,Zhencheng XU,Yiliang HE,Bo ZHANG,Song JIN,Brian BOMAN

期刊论文

Photocatalytic degradation of polybrominated diphenyl ethers in pure water system

Min ZHANG,Jian LU,Yiliang HE,P Chris WILSON

期刊论文

Polyethylene glycol-supported ionic liquid as a highly efficient catalyst for the synthesis of propylene carbonate

Rui YAO, Hua WANG, Jinyu HAN

期刊论文

Synthesis and fluorescence behavior of 2,5-diphenyl-1,3,4-oxadiazole-containing bismaleimides and bissuccinimides

Xin ZHANG, Zichen LI

期刊论文

Effect of wastewater composition on the calcium carbonate precipitation in upflow anaerobic sludge blanket

Shucheng YANG, Yanling HE, Charles CHOU, Pengxiang ZHANG, Dongqi WANG, Yonghong LIU,

期刊论文

85 nmUV降解水中二苯甲酮和孔雀石绿的动力学研究

闻瑞梅,葛伟伟

期刊论文

Novel eco-efficient reactive distillation process for dimethyl carbonate production by indirect alcoholysis

Iulian Patraşcu, Costin S. Bîldea, Anton A. Kiss

期刊论文

地下水碳酸平衡检查系统

刘建刚,郑克勋,傅伟宁,吴顺华

期刊论文

Multi-objective optimization of molten carbonate fuel cell system for reducing CO

Ramin ROSHANDEL,Majid ASTANEH,Farzin GOLZAR

期刊论文

Legacies and health risks of heavy metals, polybrominated diphenyl ethers, and polychlorinated dibenzo-dioxins

期刊论文

Effect of potassium carbonate on catalytic synthesis of calcium carbide at moderate temperature

Dejun SHI, Ke QIAO, Zifeng YAN

期刊论文

Influence of crystalline phase of Li-Al-O oxides on the activity of Wacker-type catalysts in dimethyl carbonate

Yadong GE, Yuanyuan DONG, Shengping WANG, Yujun ZHAO, Jing LV, Xinbin MA

期刊论文

碱硅酸反应与碱碳酸盐反应

唐明述

期刊论文

Direct synthesis of dimethyl carbonate over rare earth oxide supported catalyst

JIANG Qi, CHENG Jiye, GAO Zhiqin

期刊论文