Search | Engineering

订阅投稿

首页工程期刊工程焦点工程成就工程前沿关于我们 English

资源类型

期刊论文 469

年份

2023 31

2022 29

2021 43

2020 30

2019 46

2018 18

2017 23

2016 20

2015 23

2014 20

2013 21

2012 24

2011 13

2010 20

2009 21

2008 31

2007 17

2006 6

2005 3

2004 3

展开︾

关键词

微波遥感 6

微波散射计 5

微波辐射计 4

可靠性 3

HY-2 2

HY-2 卫星 2

HY-2A 2

HY-2A卫星 2

不确定性 2

人工神经网络 2

人才培养 2

可持续发展 2

扫描微波辐射计 2

泥水盾构 2

砂卵石地层 2

系统设计 2

细水雾 2

185 nmUV 1

ACMR 1

展开︾

检索范围：

排序：展示方式：

A study on the catalytic performance of Pd/γ-Al

Ruizhi CHU, Xianyong WEI, Zhimin ZONG, Wenjia ZHAO

《化学科学与工程前沿（英文）》 2010年第4卷第4期页码 452-456 doi: 10.1007/s11705-010-0522-9

摘要： A series of Pd/γ-Al O hybrid catalysts were prepared by impregnation and subsequent calcination under microwave irradiation. The catalysts were used for direct synthesis of dimethylether (DME) from syngas. The results show that calcination under microwave irradiation improved both the activity and selectivity of the catalysts for DME synthesis. The optimum power of the microwave was determined to be 420 W. Under such optimum conditions, CO conversion, DME selectivity and time space yield of DME were 60.1%, 67.0%, and 21.5 mmol·mL ·h , respectively. Based on various characterizations such as nitrogen physisorption, X-ray diffraction, CO-temperature-programmed desorption, and Fourier transform infrared spectral analysis, the promotional effect of the microwave irradiation on the catalytic property was mainly attributed to both the higher dispersion of Pd and the significant increase in the adsorption on the CO-bridge of Pd. Microwave irradiation with very high power led to the increase in CO-bridge adsorption and thereby decreased the catalytic activity, whereas the coverage by metallic Pd of the active sites on acidic γ-Al O significantly occurred under microwave irradiation with very low power, resulting in a decrease in the selectivity to DME.

关键词： Pd/γ-Al₂O₃ direct synthesis dimethyl ether calcination under microwave irradiation

HTML PDF 收藏

微波辐射下离子液体［RMIm］PF6（R=P, B, C6）的合成及其电导率研究

何永福

《中国工程科学》 2008年第10卷第9期页码 92-95

摘要：

在微波辐射下，1－甲基咪唑分别与有机卤盐(1－溴丙烷、1－溴丁烷、1－溴己烷)在80 ℃回流加热10 min，可制得咪唑类离子液体的中间体溴代1－丁基－3－甲基咪唑（［BMIm］Br）、溴代1－丙基－3－甲基咪唑（［PMIm］Br）、溴代1－己基－3－甲基咪唑（［C6MIm］Br），进一步与HPF6在室温搅拌反应4 h，制得憎水性的咪唑类离子液体［BMIm］PF6，［PMIm］PF6和［C6MIm］PF6。对这3种离子液体及其在不同有机溶剂如丙酮、甲醇、乙酸乙酯中的电导率进行测定，发现离子液体的电导率受咪

关键词：离子液体微波辐射电导率 [BMIm]PF6 [PMIm]PF6 [C6MIm]PF6

HTML PDF 收藏

Kinetics of microwave-enhanced oxidation of phenol by hydrogen peroxide

Deming ZHAO, Jie CHENG, Michael R. HOFFMANN

《环境科学与工程前沿（英文）》 2011年第5卷第1期页码 57-64 doi: 10.1007/s11783-010-0251-9

摘要： Aqueous solutions of phenol were oxidized by hydrogen peroxide assisted by microwave (MW) irradiation. A simple kinetic model for the overall degradation of phenol in the presence of excess H O is proposed in which the degradation rate of phenol is expressed as a linear function of the concentrations of phenol and H O . A detailed parametric study showed that the degradation rate of phenol increased with increasing [H O ] until saturation was observed. Phenol degradation followed apparent zero-order kinetics under MW radiation or H O oxidation. However, after 90 min of irradiation, the observed kinetics shifted to pseudo first order. The overall reaction rates were significantly enhanced in the combined MW/H O system, mainly because microwave could accelerate H O to generate hydroxyl radical ( OH) and other reactive oxygen intermediates. The observed synergetic effects of the MW/H O process resulted in an increased in the net reaction rate by a factor of 5.75. When hydrogen peroxide is present in a large stoichiometric excess, the time required to achieve complete mineralization is reduced significantly.

关键词： microwave (MW) irradiation hydrogen peroxide phenol synergetic effects kinetic model

HTML PDF 收藏

Experimental and theoretical study of microwave enhanced catalytic hydrodesulfurization of thiophene

Hui Shang, Pengfei Ye, Yude Yue, Tianye Wang, Wenhui Zhang, Sainab Omar, Jiawei Wang

《化学科学与工程前沿（英文）》 2019年第13卷第4期页码 744-758 doi: 10.1007/s11705-019-1839-7

摘要： Hydrodesulfurization (HDS) of thiophene, as a gasoline model oil, over an industrial Ni-Mo/Al O catalyst was investigated in a continuous system under microwave irradiation. The HDS efficiency was much higher (5%‒14%) under microwave irradiation than conventional heating. It was proved that the reaction was enhanced by both microwave thermal and non-thermal effects. Microwave selective heating caused hot spots inside the catalyst, thus improved the reaction rate. From the analysis of the non-thermal effect, the molecular collisions were significantly increased under microwave irradiation. However, instead of being reduced, the apparent activation energy increased. This may be due to the microwave treatment hindering the adsorption though upright S-bind (η ) and enhancing the parallel adsorption (η ), both adsorptions were considered to favor to the direct desulfurization route and the hydrogenation route respectively. Therefore, the HDS process was considered to proceed along the hydrogenation route under microwave irradiation.

关键词： thiophene microwave irradiation hydrodesulfurization non-thermal microwave effect

HTML PDF 收藏

CuO/zeolite catalyzed oxidation of gaseous toluene under microwave heating

Longli BO, Jianbo LIAO, Yucai ZHANG, Xiaohui WANG, Quan YANG

《环境科学与工程前沿（英文）》 2013年第7卷第3期页码 395-402 doi: 10.1007/s11783-012-0417-8

摘要： The development of a combined process of catalytic oxidation and microwave heating for treatment of toluene waste gas was described in this work. Toluene, a typical toxic volatile organic compound, was oxidized through a fixed bed reaction chamber containing zeolite-supported copper oxide (CuO/zeolite) catalyst mixed with silicon carbide (SiC), an excellent microwave-absorbing material. The target compound was efficiently degraded on the surface of the catalyst at high reaction temperature achieved by microwave-heated SiC. A set of experimental parameters, such as microwave power, air flow and the loading size of CuO etc., were investigated, respectively. The study demonstrated these parameters had critical impact on toluene degradation. Under optimal condition, 92% toluene was removed by this combined process, corresponding to an 80%–90% TOC removal rate. Furthermore, the catalyst was highly stable even after eight consecutive 6-h runs. At last, a hypothetical degradation pathway of toluene was proposed based on the experimental data obtained from gas chromatography-mass spectrum and Fourier transform infrared spectroscopy analyses.

关键词： microwave catalytic oxidation CuO/zeolite catalyst silicon carbide (SiC) toluene

HTML PDF 收藏

Efficient photodegradation of phenol assisted by persulfate under visible light irradiation via a nitrogen-doped

Yan Cui, Zequan Zeng, Jianfeng Zheng, Zhanggen Huang, Jieyang Yang

《化学科学与工程前沿（英文）》 2021年第15卷第5期页码 1125-1133 doi: 10.1007/s11705-020-2012-z

摘要： To realize the utilization of visible light and improve the photocatalytic efficiency of organic pollutant degradation in wastewater, a nitrogen-doped titanium-carbon composite (N-TiO /AC) prepared by sol-gel methods was applied in the photodegradation of phenol assisted by persulfate under visible light irradiation (named N-TiO /AC/PS/VIS). The results show that a synergistic effect exists between visible-light photocatalysis and persulfate activation. Compared with TiO /PS/VIS, the phenol degradation rate was found to be observably improved by 65% in the N-TiO /AC/PS/VIS system. This significant increase in degradation rate was mainly attributed to the following two factors: 1) The N and C doping can change the crystal structure of TiO , which extends the TiO absorption wavelength range to the visible light region. 2) As an electron acceptor, PS can not only prevent electrons and holes from recombining with each other but can also generate strong oxidizing radicals such as ∙SO and ∙OH to accelerate the reaction dynamics. The process of phenol degradation was found to be consistent with the Langmuir pseudo-first-order kinetic model with an apparent rate constant of 1.73 min . The N-TiO /AC/PS/VIS process was proven to be a facile method for pollutant degradation with high pH adaptability, excellent visible-light utilization and good application prospects.

关键词： N-TiO₂/AC visible light photocatalysis persulfate activation phenol

HTML PDF 收藏

Enhanced formation of trihalomethane disinfection byproducts from halobenzoquinones under combined UV

《环境科学与工程前沿（英文）》 2022年第16卷第6期 doi: 10.1007/s11783-021-1510-7

摘要：

• 2,6-DCBQ and TCBQ generated THMs differently in chlorine and UV/chlorine processes.

关键词： Halobenzoquinone Trihalomethane Chlorine disinfection UV irradiation Disinfection byproducts Combined UV/chlorine

HTML PDF 收藏

Preparation of Cu/ZnO/Al

Hui FAN, Huayan ZHENG, Zhong LI

《化学科学与工程前沿（英文）》 2010年第4卷第4期页码 445-451 doi: 10.1007/s11705-010-0521-x

摘要： Cu/ZnO/Al O catalysts with Cu/Zn/Al ratios of 6/3/1 were precipitated and aged by conventional and microwave heating methods and tested in the slurry phase reactor for methanol synthesis. The effect of technological condition of precipitation and aging process under microwave irradiation on the catalytic performance was investigated to optimize the preparing condition of Cu/ZnO/Al O catalyst. The results showed that the microwave irradiation during precipitation process could improve the activity of the catalyst, but had little effect on the stability. While the microwave irradiation during aging process has a great benefit to both the activity and stability of the catalyst, the catalyst aged at 80°C for 1 h under microwave irradiation possessed higher methanol space time yield (STY) and more stable catalytic activity. The activity and stability of the catalyst was further enhanced when microwave irradiation was used in both precipitation and aging processes; the optimized condition for the catalyst precursor preparation was precipitation at 60°C and aging at 80°C under microwave irradiation.

关键词： microwave irradiation precipitation temperature aging temperature methanol synthesis Cu/ZnO/Al₂O₃ catalyst

HTML PDF 收藏

In situ DRIFTS study of photocatalytic CO 2 reduction under UV irradiation

Jeffrey C. S. WU, Chao-Wei HUANG,

《化学科学与工程前沿（英文）》 2010年第4卷第2期页码 120-126 doi: 10.1007/s11705-009-0232-3

摘要： Photocatalytic reduction of CO on TiO and Cu/TiO photocatalysts was studied by in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) under UV irradiation. The photocatalysts were prepared by sol-gel method via controlled hydrolysis of titanium (IV) butoxide. Copper precursor was loaded onto TiO during sol-gel procedure. A large amount of adsorbed HO and surface OH groups was detected at 25°C on the TiO photocatalyst after being treated at 500°C under air stream. Carbonate and bicarbonate were formed rapidly due to the reaction of CO with oxygen-vacancy and OH groups, respectively, on TiO surface upon CO adsorption. The IR spectra indicated that, under UV irradiation, gas-phase CO further combined with oxygen-vacancy and OH groups to produce more carbonate or bicarbonate. The weak signals of reaction intermediates were found on the IR spectra, which were due to the slow photocatalytic CO reduction on photocatalysts. Photogenerated electrons merge with H ions to form H atoms, which progressively reduce CO to form formic acid, dioxymethylene, formaldehyde and methoxy as observed in the IR spectra. The well-dispersed Cu, acting as the active site significantly increases the amount of formaldehyde and dioxymethylene, thus promotes the photoactivity of CO reduction on Cu/TiO. A possible mechanism of the photocatalytic CO reduction is proposed based on these intermediates and products on the photocatalysts.

关键词： irradiation oxygen-vacancy Photocatalytic reduction Carbonate butoxide

HTML PDF 收藏

recyclable BiOBr/silk fibroin-cellulose acetate composite film for efficient photodegradation of dyes undervisible light irradiation

《化学科学与工程前沿（英文）》 2023年第17卷第11期页码 1765-1775 doi: 10.1007/s11705-023-2323-y

摘要： A stable and recyclable of BiOBr/silk fibroin-cellulose acetate composite film was prepared by blending-wet phase transformation and in situ precipitate technology. The cellulose acetate film modified by silk fibroin formed a finger-shaped porous structure, which provided a large space for the uniform growth of BiOBr nanosheets and facilitated the shuttle flow of dyes in film. The morphology, phase structure, and optical properties of the composite films were characterized using various techniques, and their photocatalytic performance for dye wastewater was evaluated under visible light irradiation. Results showed that the BiOBr/SF-CA composite film exhibited efficient photocatalytic activity with 99.9% of rhodamine B degradation rate. Moreover, the composite film maintained high catalytic stability because Bi as the active species deposited on the film showed almost no loss. Finally, the possible photocatalytic mechanisms in the BiOBr/SF-CA composite film were speculated through radical-trapping experiments and electron spin resonance testing.

关键词： BiOBr nanosheet cellulose acetate silk fibroin photocatalytic degradation dye wastewater

HTML PDF 收藏

All-inorganic TiO/CsAgBiBr composite as highly efficient photocatalyst under visible light irradiation

《化学科学与工程前沿（英文）》 2023年第17卷第12期页码 1925-1936 doi: 10.1007/s11705-023-2344-6

摘要： In recent years, limited photocatalysis efficiency and wide band gap have hindered the application of TiO₂ in the field of photocatalysis. A leading star in photocatalysis has been revealed as lead-free Cs₂AgBiBr₆ double halide perovskite nanocrystals, owing to its strong visible light absorption and tunable band gap. In this work, this photocatalytic process was facilitated by a unique TiO₂/Cs₂AgBiBr₆ composite, which was identified as an S-cheme heterojunction. TiO₂/Cs₂AgBiBr₆ composite was investigated for its structure and photocatalytic behavior. The results showed that when the perovskite dosage is 40%, the photocatalytic rate of TiO₂ could be boosted to 0.1369 min^–1. This paper discusses and proposes the band gap matching, carrier separation, and photocatalytic mechanism of TiO₂/Cs₂AgBiBr₆ composites, which will facilitate the generation of new ideas for improving TiO₂’s photocatalytic performance.

关键词： Cs₂AgBiBr₆ nanocrystals visible-light photocatalyst Cs₂AgBiBr₆/TiO₂ heterojunction

HTML PDF 收藏

Decomposition of aqueous chlorinated contaminants by UV irradiation with H

Eunsung KAN,Chang-Il KOH,Kyunghyuk LEE,Joonwun KANG

《环境科学与工程前沿（英文）》 2015年第9卷第3期页码 429-435 doi: 10.1007/s11783-014-0677-6

摘要： In the present study, the decomposition rates of carbon tetrachloride (CCl ) and 2,4-dichlorophenol (2,4-DCP) in water by the ultraviolet (UV) light irradiation alone and H O /UV were experimentally investigated. The detailed experimental studies have been conducted for examining treatment capacities of the two different ultraviolet light sources (low and medium pressure Hg arc) in H O /UV processes. The low or medium UV lamp alone resulted in a 60%–90% decomposition of 2,4-DCP while a slight addition of H O resulted in a drastic enhancement of the 2,4-DCP decomposition rate. The decomposition rate of 2,4-DCP with the medium pressure UV lamp alone was about 3–6 times greater than the low pressure UV lamp alone. In the direct photolysis of aqueous CCl , the medium pressure UV lamp had advantage over the low pressure UV lamp because the molar extinction coefficient of CCl at shorter wavelength (210–220 nm) is about 20 to 50 times higher than that at 254 nm. However, adding H O to the medium pressure UV lamp system rendered a negative oxidation rate because H O acted as a UV absorber being competitive with CCl due to negligible reaction between CCl and OH radicals. The results from the present study indicated significant influence of the photochemical properties of the target contaminants on the photochemical treatment characteristics for designing cost-effective UV-based degradation of toxic contaminants.

关键词： H₂O₂/ultraviolet (UV) light advanced oxidation UV light irradiation chlorinated contaminants photochemical treatment characteristics

HTML PDF 收藏

Effect of ultraviolet irradiation and chlorination on ampicillin-resistant

Yuchen PANG,Jingjing HUANG,Jinying XI,Hongying HU,Yun ZHU

《环境科学与工程前沿（英文）》 2016年第10卷第3期页码 522-530 doi: 10.1007/s11783-015-0779-9

摘要： Antibiotic resistance is a serious public health risk that may spread via potable and reclaimed water. Effective disinfection is important for inactivation of antibiotic-resistant bacteria and disruption of antibiotic resistance genes. Ampicillin is a widely prescribed antibiotic but its effectiveness is increasingly undermined by resistance. In this study, changes in ampicillin resistance for ( ) CGMCC 1.1595 were analyzed after exposure to different doses of ultraviolet (UV) or chlorine, and damage incurred by the plasmid encoding ampicillin resistance gene was assessed. We reported a greater stability in ampicillin-resistant CGMCC 1.1595 after UV irradiation or chlorination when compared with previously published data for other strains. UV irradiation and chlorination led to a shift in the mortality frequency distributions of ampicillin-resistant when subsequently exposed to ampicillin. The ampicillin hemi-inhibitory concentration (IC ) without disinfection was 3800 mg·L , and an increment was observed after UV irradiation or chlorination. The IC of ampicillin-resistant was 1.5-fold higher at a UV dose of 40 mJ·cm , and was 1.4-fold higher when exposed to 2.0 mg·L chlorine. These results indicate that UV irradiation and chlorination can potentially increase the risk of selection for strains with high ampicillin resistance. There was no evident damage to after 1–10 mg Cl ·L chlorination, while a UV dose of 80 mJ·cm yielded a damage ratio for of approximately 1.2-log. Therefore, high UV doses are required for effective disruption of antibiotic resistance genes in bacteria.

关键词： antibiotic resistance Escherichia coli ampicillin resistance gene ultraviolet irradiation chlorination

HTML PDF 收藏

Use of gamma-irradiation pretreatment for enhancement of anaerobic digestibility of sewage sludge

YUAN Shoujun, ZHENG Zheng, YU Xin, ZHAO Yongfu, MU Yanyan

《环境科学与工程前沿（英文）》 2008年第2卷第2期页码 247-250 doi: 10.1007/s11783-008-0041-9

摘要： The effects of ?-irradiation pretreatment on anaerobic digestibility of sewage sludge was investigated in this paper. Parameters like solid components, soluble components, and biogas production of anaerobic digestion experiment for sewage sludge were measured. The values of these parameters were compared before and after ?-irradiation pretreatment. Total solid (TS), volatile solid (VS), suspended solid (SS), volatile suspended solid (VSS), and average floc size of samples decreased after ?-irradiation treatment. Besides, floc size distribution of sewage sludge shifted from 80–100 ?m to 0–40 ?m after ?-irradiation treatment at the doses from 0 to 30 kGy, which indicated the disintegration of sewage sludge. Moreover, microbe cells of sewage sludge were ruptured by ?-irradiation treatment, which resulted in the release of cytoplasm and increase of soluble chemical oxygen demand (SCOD). Both sludge disintegration and microbe cells rupture enhanced the subsequent anaerobic digestion process, which was demonstrated by the increase of accumulated biogas production. Compared with digesters fed with none irradiated sludge, the accumulated biogas production increased 44, 98, and 178 mL for digesters fed sludge irradiated at 2.48, 6.51, and 11.24 kGy, respectively. The results indicated that ?-irradiation pretreatment could effectively enhance anaerobic digestibility of sewage sludge, and correspondingly, could accelerate hydrolysis process, shorten sludge retention time of sludge anaerobic digestion process.

关键词： anaerobic digestibility soluble chemical cytoplasm digestion process soluble

HTML PDF 收藏

Effects of irradiation on chromium’s behavior in ferritic/martensitic FeCr alloy

Xinfu HE, Wen YANG, Zhehao QU, Sheng FAN

《能源前沿（英文）》 2009年第3卷第2期页码 181-183 doi: 10.1007/s11708-009-0025-x

摘要： The effects of irradiation on chromium performance under different temperatures in Fe-20at%Cr were modeled by modified Marlowe code. Chromium precipitation was observed in FeCr alloy after irradiation; interstitial Chromium atoms are the preferred formation of mixed Fe-Cr dumbbells in the direction of<110>and<111>; interstitial chromium atoms congregated on {111} and {110} plane. The results are compared with experiment observations and are useful to understanding the irradiation performances of FeCr alloy.

关键词： irradiation Fe-20at%Cr alloy chromium segregation