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Cu(In 4

Ga)Se₂ 3

5G 2

CCS 2

CO₂利用 2

CO₂封存 2

CO₂捕集 2

二氧化碳 2

代谢 2

低碳发展 2

催化剂 2

光催化 2

碳中和 2

纳米颗粒 2

高温气冷堆 2

&alpha 1

(GaxIn1−x)2O3薄膜；带隙可调谐；磁控溅射 1

(美国) 核管理委员会 1

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Enhancing the aromatic selectivity of cyclohexane aromatization by CO2sub> coupling

《化学科学与工程前沿（英文）》 2023年第17卷第11期页码 1801-1808 doi: 10.1007/s11705-023-2325-9

摘要： Improving the aromatic selectivity in the alkane aromatization process is of great importance for its practical utilization but challenge to make because the high H/C ratio of alkanes would lead to a serious hydrogen transfer process and a large amount of light alkanes. Herein, CO₂ is introduced into the cyclohexane conversion process on the HZSM-5 zeolite, which can improve the aromatic selectivity. By optimizing the reaction conditions, an improved aromatic (benzene, toluene, xylene, and C₉₊) selectivity of 48.2% can be obtained at the conditions of 2.7 MPa (CO₂), 450 °C, and 1.7 h⁻¹, which is better than that without CO₂ (aromatic selectivity = 43.2%). In situ transmission Fourier transform infrared spectroscopy spectra illustrate that many oxygenated chemical intermediates (e.g., carboxylic acid, anhydride, unsaturated aldehydes/ketones or ketene) would be formed during the cyclohexane conversion process in the presence of CO₂. ¹³C isotope labeling experimental results demonstrate that CO₂ can enter into the aromatics through the formation of oxygenated chemical intermediates and thereby improve the aromatic selectivity. This study may open a green, economic, and promising way to improve the aromatic selectivity for alkane aromatization process.

关键词： aromatics carbon dioxide aromatization coupling reaction ZSM-5 zeolite

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The modification of titanium in mesoporous silica for Co-based Fischer–Tropsch catalysts

《化学科学与工程前沿（英文）》 2022年第16卷第8期页码 1224-1236 doi: 10.1007/s11705-022-2139-1

摘要： Ordered SBA-15 mesoporous silica with incorporated titanium was successfully synthesized via a one-pot hydrothermal crystallization method. The characterization including powder X-ray diffraction, Brunauer–Emmett–Teller, transmission electron microscope, temperature-programmed reduction, temperature-programmed desorption, Fourier transform infrared and ultraviolet-visible-near infrared spectrometer was performed to explore the physical and chemical structures of both the supports and the catalysts. The results showed that titanium was successfully incorporated into the mesoporous silica framework with a limited amount of titanium (Si/Ti > 20), and the mesoporous structure was retained. However, the increased titanium content inevitably resulted in the formation of anatase TiO ₂ particles on the support surface. The increased incorporated titanium strengthened the interactions between cobalt species and supports, which was favorable for the cobalt species dispersion, despite the limited cobalt oxide reducibility. The enhanced metal-support interactions were beneficial for the CO/H₂ ratio at the active cobalt sites, which facilitated the formation of more C₅₊ hydrocarbons. This study provides a promising method for support modification with incorporated-heteroatoms for the rational development of Fischer–Tropsch catalysts.

关键词： Fischer–Tropsch synthesis titanium incorporation mesoporous silica metal-support interactions C₅₊ selectivity

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Facile controlled synthesis of hierarchically structured mesoporous Li4Ti5O12/C/rGO composites as high-performance

Cehuang FU, Shuiyun SHEN, Ruofei WU, Xiaohui YAN, Guofeng XIA, Junliang ZHANG

《能源前沿（英文）》 2022年第16卷第4期页码 607-612 doi: 10.1007/s11708-021-0798-0

摘要： In this paper, a facile strategy is proposed to controllably synthesize mesoporous Li₄Ti₅O₁₂/C nanocomposite embedded in graphene matrix as lithium-ion battery anode via the co-assembly of Li₄Ti₅O₁₂ (LTO) precursor, GO, and phenolic resin. The obtained composites, which consists of a LTO core, a phenolic-resin-based carbon shell, and a porous frame constructed by rGO, can be denoted as LTO/C/rGO and presents a hierarchical structure. Owing to the advantages of the hierarchical structure, including a high surface area and a high electric conductivity, the mesoporous LTO/C/rGO composite exhibits a greatly improved rate capability as the anode material in contrast to the conventional LTO electrode.

关键词： Li₄Ti₅O₁₂ phenolic-resin-based carbon mesoporous composite graphene

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Effects of ancillary ligands in acceptorless benzyl alcohol dehydrogenation mediated by phosphine-free cobalt complexes

《化学科学与工程前沿（英文）》 2023年第17卷第3期页码 314-325 doi: 10.1007/s11705-022-2219-2

摘要： Acceptorless alcohol dehydrogenation stands out as one of the most promising strategies in hydrogen storage technologies. Among various catalytic systems for this reaction, cost-effective molecular catalysts using phosphine-free ligands have gained considerable attention. However, the central challenge for using non-precious metals is to overcome the propensity of reacting by one-electron pathway. Herein, we synthesized a phosphine-free η⁵-C₅Me₅-Co complex by using the metal–ligand cooperative strategy and compared its activity with analogous catalysts toward acceptorless alcohol dehydrogenation. The catalyst showed excellent performance with a turnover number of 130.4 and a selectivity close to 100%. The improved performance among the class of η⁵-C₅Me₅-Co complexes could be attributed to the more accessible Co center and its cooperation with the redox-active ligand. To further study the systematic structure-activity relationship, we investigated the electronic structures of η⁵-C₅Me₅-Co complexes by a set of characterizations. The results showed that the redox-active ligand has a significant influence on the η⁵-C₅Me₅-Co moiety. In the meantime, the proximal O⁻/OH group is beneficial for shuttling protons. For the catalytic cycle, two dehydrogenation scenarios were interrogated through density functional theory, and the result suggested that the outer-sphere pathway was preferred. The formation of a dihydrogen complex was the rate-determining step with a ΔG value of 16.9 kcal∙mol^‒1. The electron population demonstrated that the η⁵-C₅Me₅ ligand played a key role in stabilizing transition states during dehydrogenation steps. This work identified the roles of vital ligand components to boost catalytic performance and offered rationales for designing metal–ligand cooperative nonprecious metal complexes.

关键词： acceptorless alcohol dehydrogenation η⁵-C₅Me₅-Co metal–ligand cooperation theoretical calculation

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An investigation of the CHOH and CO selectivity of CO hydrogenation over Cu–Ce–Zr catalysts

《化学科学与工程前沿（英文）》 2022年第16卷第6期页码 950-962 doi: 10.1007/s11705-022-2162-2

摘要： A series of Cu–Ce–Zr catalysts with different Ce contents are applied to the hydrogenation of CO₂ to CO/CH₃OH products. The Cu–Ce–Zr catalyst with 2 wt% Ce loading shows higher CO selectivity (S_CO = 0.0%–87.8%) from 200–300 °C, while the Cu–Ce–Zr catalyst with 8 wt% Ce loading presents higher CO₂ conversion (

X C O 2

= 5.4%–15.6%) and CH₃OH selectivity (

S C H 3 O H

= 97.8%–40.6%). The number of hydroxyl groups and solid solution nature play a significant role in changing the reaction pathway. The solid solution enhances the CO₂ adsorption ability. At the CO₂ adsorption step, a larger number of hydroxyl groups over the Cu–Ce–Zr catalyst with 8 wt% Ce loading leads to the production of H-containing adsorption species. At the CO₂ hydrogenation step, a larger number of hydroxyl groups assists in encouraging the further hydrogenation of intermediate species to CH₃OH and improving the hydrogenation rate. Hence, the Cu–Ce–Zr catalyst with 8 wt% Ce loading favors CH₃OH selectivity and CO₂ activation, while CO is preferred on the Cu–Ce–Zr catalyst with 2 wt% Ce loading, a smaller number of hydroxyl groups and a solid solution nature. Additionally, high-pressure in situ diffuse reflectance infrared Fourier transform spectroscopy shows that CO is produced from formate decomposition and that both monodentate formate and bidentate formate are active intermediate species of CO₂ hydrogenation to CH₃OH.

关键词： CO₂ hydrogenation Cu–Ce–Zr hydroxyls CO/CH₃OH selectivity

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Tuning the catalytic selectivity in electrochemical CO

Jiafang XIE,Yuxi HUANG,Hanqing YU

《环境科学与工程前沿（英文）》 2015年第9卷第5期页码 861-866 doi: 10.1007/s11783-014-0742-1

摘要： Electrochemical conversion of CO to hydrocarbons can relieve both environmental and energy stresses. However, electrocatalysts for this reaction usually suffer from a poor product selectivity and a large overpotential. Here we report that tunable catalytic selectivity for hydrocarbon formation could be achieved on Cu nanomaterials with different morphologies. By tuning the electrochemical parameters, either Cu oxide nanowires or nanoneedles were fabricated and then electrochemically reduced to the corresponding Cu nanomaterials. The Cu nanowires preferred the formation of C H , while the Cu nanoneedles favored the production of more CH , rather than C H . Our work provides a facile synthetic strategy for preparing Cu-based nanomaterials to achieve selective CO reduction.

关键词： electrochemical CO₂ reduction Cu oxide nanostructure selectivity hydrocarbon formation

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天然气提质过程中可有效回收丙烷和乙烷的高工业应用潜力金属有机框架材料 Article

咸士凯, 彭俊杰, Haardik Pandey, Timo Thonhauser, 王浩, 李静

《工程（英文）》 2023年第23卷第4期页码 56-63 doi: 10.1016/j.eng.2022.07.017

摘要：

开发具有高吸收和选择性的高效吸附剂用于从天然气中分离和回收C2sub>H6sub>和C3sub>H8sub>是一项重要但具有挑战性的任务。值得注意的是，MOF-303 在298 K和5 kPa 下对C3H8的吸收高达3.38 mmol∙g⁻¹，C3sub>H8sub>/CH4sub> (5:85, V/V)理想吸附溶液理论（IAST）选择性为5114，在所有已报道的MOF中创下新高。C3sub>H8sub>和C2sub>H6sub>的高负载能力和选择性。此外，这两种化合物的合成都可以很容易地通过一锅反应来放大规模，从而获得约5 g 的高结晶度样品。

关键词：金属-有机框架，烃类吸附和分离，选择性，稳定性，放大合成

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On the monolayer dispersion behavior of Co3sub>O4sub> on HZSM-5 support: designing applicable

《化学科学与工程前沿（英文）》 2023年第17卷第11期页码 1741-1754 doi: 10.1007/s11705-023-2332-x

摘要： Based on monolayer dispersion theory, Co₃O₄/ZSM-5 catalysts with different loadings have been prepared for selective catalytic reduction of nitrogen oxides by ammonia. Co₃O₄ can spontaneously disperse on HZSM-5 support with a monolayer dispersion threshold of 0.061 mmol 100 m^–2, equaling to a weight percentage around 4.5%. It has been revealed that the quantities of surface active oxygen (O₂^–) and acid sites are crucial for the reaction, which can adsorb and activate NO_x and NH₃ reactants effectively. Below the monolayer dispersion threshold, Co₃O₄ is finely dispersed as sub-monolayers or monolayers and in an amorphous state, which is favorable to generate the two kinds of active sites, hence promoting the performance of ammonia selective catalytic reduction of nitrogen oxide. However, the formation of crystalline Co₃O₄ above the capacity is harmful to the reaction performance. 4% Co₃O₄/ZSM-5, the catalyst close to the monolayer dispersion capacity, possesses the most abundant active O₂^– species and acidic sites, thereby demonstrating the best reaction performance in all the samples. It is proposed the optimal Co₃O₄/ZSM-5 catalyst can be prepared by loading the capacity amount of Co₃O₄ onto HZSM-5 support.

关键词： Co₃O₄/ZSM-5 NO_x-SCR by NH₃ monolayer dispersion threshold effect surface acid sites surface active O₂^– anions

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NO hydrogenation to NH over FeCu/TiO catalyst with improved activity

《化学科学与工程前沿（英文）》 2023年第17卷第12期页码 1973-1985 doi: 10.1007/s11705-023-2364-2

摘要： Ammonia is crucial in industry and agriculture, but its production is hindered by environmental concerns and energy-intensive processes. Hence, developing an efficient and environmentally friendly catalyst is imperative. In this study, we employed a straightforward and efficient impregnation technique to create various Cu-doped catalysts. Notably, the optimized 10Fe-8Cu/TiO₂ catalyst exhibited exceptional catalytic performance in converting NO to NH₃, achieving an NO conversion rate exceeding 80% and an NH₃ selectivity exceeding 98% at atmospheric pressure and 350 °C. We employed in situ diffuse reflectance Fourier transform infrared spectroscopy and conducted density functional theory calculations to investigate the intermediates and subsequent adsorption. Our findings unequivocally demonstrate that Cu doping enhances the rate-limiting hydrogenation step and lowers the energy barrier for NH₃ desorption, thereby resulting in improved NO conversion and enhanced selectivity toward ammonia. This study presents a pioneering approach toward energy-efficient ammonia synthesis and recycling of nitrogen sources.

关键词： NO hydrogenation synthetic ammonia 10Fe-xCu/TiO₂ high selectivity

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Bioinspired C/TiO

Jian LI, Likun GAO, Wentao GAN

《农业科学与工程前沿（英文）》 2017年第4卷第4期页码 459-464 doi: 10.15302/J-FASE-2017178

摘要： butterfly wings were replicated by a sol-gel method and a calcination process, which could take advantage of the spatial features of the wing to enhance their photocatalytic properties. Hierarchical structures of -carbon-TiO (PP-C-TiO ) were confirmed by SEM observations. By applying the Brunauer-Emmett-Teller method, it was concluded that in the presence of wings the product shows higher surface area with respect to the pure TiO made in the absence of the wings. The higher specific surface area is also beneficial for the improvement of photocatalytic property. Furthermore, the conduction and valence bands of the PP-C-TiO are more negative than the corresponding bands of pure TiO , allowing the electrons to migrate from the valence band to the conduction band upon absorbing visible light. That is, the presence of C originating from wings in the PP-C-TiO could extend the photoresponsiveness to visible light. This strategy provides a simple method to fabricate a high-performance photocatalyst, which enables the simultaneous control of the morphology and carbon element doping.

关键词： bioinspired butterfly wings C/TiO₂ photocatalyst visible light

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Characterization and performance of V

Caiting LI, Qun LI, Pei LU, Huafei CUI, Guangming ZENG

《环境科学与工程前沿（英文）》 2012年第6卷第2期页码 156-161 doi: 10.1007/s11783-010-0295-x

摘要： A series of CeO supported V O catalysts with various loadings were prepared with different calcination temperatures by the incipient impregnation. The catalysts were evaluated for low temperature selective catalytic reduction (SCR) of NO with ammonia (NH ). The effects of O and SO on catalytic activity were also studied. The catalysts were characterized by specific surface areas (S ) and X–ray diffraction (XRD) methods. The experimental results showed that NO conversion changed significantly with the different V O loading and calcination temperature. With the V O loading increasing from 0 to 10 wt%, NO conversion increased significantly, but decreased at higher loading. The optimum calcination temperature was 400°C. The best catalyst yielded above 80% NO conversion in the reaction temperature range of 160°C–300°C. The formation of CeVO on the surface of catalysts caused the decrease of redox ability.

关键词： V₂O₅/CeO₂ catalysts NH₃-SCR (selective catalytic reduction) the incipient impregnation low temperatures

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Recent advances in special morphologic photocatalysts for NO removal

《环境科学与工程前沿（英文）》 2022年第16卷第11期 doi: 10.1007/s11783-022-1573-0

摘要：

● Systematic information of recent progress in photocatalytic NO_x removal is provided.

关键词： NO_x removal Photocatalyst Graphene C₃N₄ Bi-based compounds.

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Physical and chemical processes of wintertime secondary nitrate aerosol formation

Qi YING

《环境科学与工程前沿（英文）》 2011年第5卷第3期页码 348-361 doi: 10.1007/s11783-011-0343-1

摘要： The UCD/CIT model was modified to include a process analysis (PA) scheme for gas and particulate matter (PM) to study the formation of secondary nitrate aerosol during a stagnant wintertime air pollution episode during the California Regional PM /PM Air Quality Study (CRPAQS) where detailed measurements of PM components are available at a few sites. Secondary nitrate is formed in the urban areas from near the ground to a few hundred meters above the surface during the day with a maximum modeled net increase rate of 4 μg·m ·d during the study episode. The secondary nitrate formation rate in rural areas is lower due to lower NO . In the afternoon hours, near-surface temperature can be high enough to evaporate the particulate nitrate. In the nighttime hours, both the gas phase N O reactions with water vapor and the N O heterogeneous reactions with particle-bound water are important for secondary nitrate formation. The N O reactions are most import near the surface to a few hundred meters above surface with a maximum modeled net secondary nitrate increase rate of 1 μg·m ·d and are more significant in the rural areas where the O concentrations are high at night. In general, vertical transport during the day moves the nitrate formed near the surface to higher elevations. During the stagnant days, process analysis indicates that the nitrate concentration in the upper air builds up and leads to a net downward flux of nitrate through vertical diffusion and a rapid increase of surface nitrate concentration.

关键词： secondary nitrate aerosol N₂O₅ heterogeneous reaction process analysis

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Chemical deactivation of V

Xiaodong WU, Wenchao YU, Zhichun SI, Duan WENG

《环境科学与工程前沿（英文）》 2013年第7卷第3期页码 420-427 doi: 10.1007/s11783-013-0489-0

摘要： V O -WO /TiO catalyst was poisoned by impregnation with NH Cl, KOH and KCl solution, respectively. The catalysts were characterized by X-ray diffraction (XRD), inductively coupled plasma (ICP), N physisorption, Raman, UV-vis, NH adsorption, temperature-programmed reduction of hydrogen (H -TPR), temperature-programmed oxidation of ammonia (NH -TPO) and selective catalytic reduction of NO with ammonia (NH -SCR). The deactivation effects of poisoning agents follow the sequence of KCl>KOH>>NH Cl. The addition of ammonia chloride enlarges the pore size of the titania support, and promotes the formation of highly dispersed V=O vanadyl which improves the oxidation of ammonia and the high-temperature SCR activity. K ions are suggested to interact with vanadium and tungsten species chemically, resulting in a poor redox property of catalyst. More importantly, potassium can reduce the Br?nsted acidity of catalysts and decrease the stability of Br?nsted acid sites significantly. The more severe deactivation of the KCl-treated catalyst can be mainly ascribed to the higher amount of potassium resided on catalyst.

关键词： V₂O₅-WO₃/TiO₂ potassium chloride poisoning reducibility acid sites

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Pd/Fe3O4 supported on bio-waste derived cellulosic-carbon as a nanocatalyst for C–C coupling and electrocatalytic

《化学科学与工程前沿（英文）》 2022年第16卷第10期页码 1514-1525 doi: 10.1007/s11705-022-2158-y

摘要： The current work describes the synthesis of a new bio-waste derived cellulosic-carbon supported-palladium nanoparticles enriched magnetic nanocatalyst (Pd/Fe₃O₄@C) using a simple multi-step process under aerobic conditions. Under mild reaction conditions, the Pd/Fe₃O₄@C magnetic nanocatalyst demonstrated excellent catalytic activity in the Hiyama cross-coupling reaction for a variety of substrates. Also, the Pd/Fe₃O₄@C magnetic nanocatalyst exhibited excellent catalytic activity up to five recycles without significant catalytic activity loss in the Hiyama cross-coupling reaction. Also, we explored the use of Pd/Fe₃O₄@C magnetic nanocatalyst as an electrocatalyst for hydrogen evolution reaction. Interestingly, the Pd/Fe₃O₄@C magnetic nanocatalyst exhibited better electrochemical activity compared to bare carbon and magnetite (Fe₃O₄ nanoparticles) with an overpotential of 293 mV at a current density of 10 mA·cm^–2.

关键词： bio-waste cellulosic-carbon Pd/Fe₃O₄ Hiyama cross-coupling hydrogen evolution reaction recyclability