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 1917

会议视频 93

会议信息 14

会议专题 1

年份

2024 3

2023 242

2022 308

2021 275

2020 163

2019 107

2018 72

2017 83

2016 73

2015 78

2014 72

2013 80

2012 48

2011 46

2010 70

2009 59

2008 59

2007 72

2006 17

2005 8

展开︾

关键词

3D打印 13

绿色化工 9

院士大会 9

增材制造 8

SARS-CoV-2 7

人工智能 7

2020 6

工程管理 6

抗击疫情 6

营养健康 6

医学 5

微波散射计 5

碳中和 5

经济 5

2019 4

4D打印 4

COVID-19 4

Cu(In 4

HY-2 4

展开︾

检索范围：

排序：展示方式：

Ultrasound-assisted co-precipitation synthesis of mesoporous Co3O4–CeO2 composite oxides for highly selective

《化学科学与工程前沿（英文）》 2022年第16卷第8期页码 1211-1223 doi: 10.1007/s11705-022-2145-3

摘要： The one-step highly selective oxidation of cyclohexane into cyclohexanone and cyclohexanol as the essential intermediates of nylon-6 and nylon-66 is considerably challenging. Therefore, an efficient and low-cost catalyst must be urgently developed to improve the efficiency of this process. In this study, a Co₃O₄–CeO₂ composite oxide catalyst was successfully prepared through ultrasound-assisted co-precipitation. This catalyst exhibited a higher selectivity to KA-oil, which was benefited from the synergistic effects between Co³⁺/Co²⁺ and Ce⁴⁺/Ce³⁺ redox pairs, than bulk CeO₂ and/or Co₃O₄. Under the optimum reaction conditions, 89.6% selectivity to KA-oil with a cyclohexane conversion of 5.8% was achieved over Co₃O₄–CeO₂. Its catalytic performance remained unchanged after five runs. Using the synergistic effects between the redox pairs of different transition metals, this study provides a feasible strategy to design high-performance catalysts for the selective oxidation of alkanes.

关键词： Co₃O₄–CeO₂ composite oxides cyclohexanone cyclohexanol ultrasonic-assisted co-precipitation selective oxidation solvent-free

HTML PDF 收藏

On the monolayer dispersion behavior of Co₃O₄ on HZSM-5 support: designing applicablecatalysts for selective catalytic reduction of nitrogen oxides by ammonia

《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

HTML PDF 收藏

Al₂O₃ and CeO₂-promoted MgO sorbents for CO₂ capture at moderate

Huimei Yu, Xiaoxing Wang, Zhu Shu, Mamoru Fujii, Chunshan Song

《化学科学与工程前沿（英文）》 2018年第12卷第1期页码 83-93 doi: 10.1007/s11705-017-1691-6

摘要： A series of Al O and CeO modified MgO sorbents was prepared and studied for CO sorption at moderate temperatures. The CO sorption capacity of MgO was enhanced with the addition of either Al O or CeO . Over Al O -MgO sorbents, the best capacity of 24.6 mg-CO /g-sorbent was attained at 100 °C, which was 61% higher than that of MgO (15.3 mg-CO /g-sorbent). The highest capacity of 35.3 mg-CO /g-sorbent was obtained over the CeO -MgO sorbents at the optimal temperature of 200 °C. Combining with the characterization results, we conclude that the promotion effect on CO sorption with the addition of Al O and CeO can be attributed to the increased surface area with reduced MgO crystallite size. Moreover, the addition of CeO increased the basicity of MgO phase, resulting in more increase in the CO capacity than Al O promoter. Both the Al O -MgO and CeO -MgO sorbents exhibited better cyclic stability than MgO over the course of fifteen CO sorption-desorption cycles. Compared to Al O , CeO is more effective for promoting the CO capacity of MgO. To enhance the CO capacity of MgO sorbent, increasing the basicity is more effective than the increase in the surface area.

关键词： CO₂ capture MgO sorbents Al₂O₃ CeO₂ flue gas

HTML PDF 收藏

ZnFe₂O₄ deposited on BiOCl with exposed (001) and (010) facets for photocatalyticreduction of CO₂ in cyclohexanol

Guixian Song, Xionggang Wu, Feng Xin, Xiaohong Yin

《化学科学与工程前沿（英文）》 2017年第11卷第2期页码 197-204 doi: 10.1007/s11705-016-1606-y

摘要： ZnFe O -BiOCl composites were prepared by both hydrothermal and direct precipitation processes and the structures and properties of the samples were characterized by various instrumental techniques. The samples were then used as catalysts for the photocatalytic reduction of CO in cyclohexanol under ultraviolet irradiation to give cyclohexanone (CH) and cyclohexyl formate (CF). The photocatalytic CO reduction activities over the hydrothermally prepared ZnFe O -BiOCl composites were higher than those over the directly-precipitated composites. This is because compared to the direct-precipitation sample, the ZnFe O nanoparticles in the hydrothermal sample were smaller and more uniformly distributed on the surface of BiOCl and so more heterojunctions were formed. Higher CF and CH yields were obtained for the pure BiOCl and BiOCl composite samples with more exposed (001) facets than for the samples with more exposed (010) facets. This is due to the higher density of oxygen atoms in the exposed (001) facets, which creates more oxygen vacancies, and thereby improves the separation efficiency of the electron-hole pairs. More importantly, irradiation of the (001) facets with ultraviolet light produces photo-generated electrons which is helpful for the reduction of CO to ·CO . The mechanism for the photocatalytic reduction of CO in cyclohexanol over ZnFe O -BiOCl composites with exposed (001) facets involves electron transfer and carbon radical formation.

关键词： reduction of CO₂ cyclohexanol ZnFe₂O₄ deposited BiOCl facet composite photocatalyst

HTML PDF 收藏

Rh₂O₃/hexagonal CePO₄ nanocatalysts for N₂O decomposition

Huan Liu, Zhen Ma

《化学科学与工程前沿（英文）》 2017年第11卷第4期页码 586-593 doi: 10.1007/s11705-017-1659-6

摘要： Hexagonal CePO nanorods were prepared by a precipitation method and hexagonal CePO nanowires were prepared by hydrothermal synthesis at 150 °C. Rh(NO ) was then used as a precursor for the impregnation of Rh O onto these CePO materials. The Rh O supported on the CePO nanowires was much more active for the catalytic decomposition of N O than the Rh O supported on CePO nanorods. The stability of both catalysts as a function of time on stream was studied and the influence of the co-feed (CO , O , H O or O /H O) on the N O decomposition was also investigated. The samples were characterized by N adsorption-desorption, inductively coupled plasma optical emission spectroscopy, X-ray diffraction, transmission electron microscopy, X-ray photoelectron microscopy, hydrogen temperature-programmed reduction, oxygen temperature-programmed desorption, and CO temperature-programmed desorption in order to correlate the physicochemical and catalytic properties.

关键词： Rh₂O₃ CePO₄ N₂O decomposition

HTML PDF 收藏

NiCo2O4@quinone-rich N–C core–shell nanowires as composite electrode for electric double layer capacitor

《化学科学与工程前沿（英文）》 2023年第17卷第4期页码 373-386 doi: 10.1007/s11705-022-2223-6

摘要： The bind-free carbon cloth-supported electrodes hold the promises for high-performance electrochemical capacitors with high specific capacitance and good cyclic stability. Considering the close connection between their performance and the amount of carbon material loaded on the electrodes, in this work, NiCo₂O₄ nanowires were firstly grown on the substrate of active carbon cloth to provide the necessary surface area in the longitudinal direction. Then, the quinone-rich nitrogen-doped carbon shell structure was formed around NiCo₂O₄ nanowires, and the obtained composite was used as electrode for electric double layer capacitor. The results showed that the composite electrode displayed an area-specific capacitance of 1794 mF∙cm^–2 at the current density of 1 mA∙cm^–2. The assembled symmetric electric double layer capacitor achieved a high energy density of 6.55 mW∙h∙cm^–3 at a power density of 180 mW∙cm^–3. The assembled symmetric capacitor exhibited a capacitance retention of 88.96% after 10000 charge/discharge cycles at the current density of 20 mA∙cm^–2. These results indicated the potentials in the preparation of the carbon electrode materials with high energy density and good cycling stability.

关键词： carbon cloth NiCo₂O₄ nanowires core−shell structure quinone-rich electric double layer capacitor

HTML PDF 收藏

CO₂ methanation and co-methanation of CO and CO₂ over Mn-promoted Ni/Al₂O₃ catalysts

Kechao Zhao,Zhenhua Li,Li Bian

《化学科学与工程前沿（英文）》 2016年第10卷第2期页码 273-280 doi: 10.1007/s11705-016-1563-5

摘要： A series of Mn-promoted 15 wt-% Ni/Al O catalysts were prepared by an incipient wetness impregnation method. The effect of the Mn content on the activity of the Ni/Al O catalysts for CO methanation and the co-methanation of CO and CO in a fixed-bed reactor was investigated. The catalysts were characterized by N physisorption, hydrogen temperature-programmed reduction and desorption, carbon dioxide temperature-programmed desorption, X-ray diffraction and high-resolution transmission electron microscopy. The presence of Mn increased the number of CO adsorption sites and inhibited Ni particle agglomeration due to improved Ni dispersion and weakened interactions between the nickel species and the support. The Mn-promoted 15 wt-% Ni/Al O catalysts had improved CO methanation activity especially at low temperatures (250 to 400 °C). The Mn content was varied from 0.86% to 2.54% and the best CO conversion was achieved with the 1.71Mn-Ni/Al O catalyst. The co-methanation tests on the 1.71Mn-Ni/Al O catalyst indicated that adding Mn markedly enhanced the CO methanation activity especially at low temperatures but it had little influence on the CO methanation performance. CO methanation was more sensitive to the reaction temperature and the space velocity than the CO methanation in the co-methanation process.

关键词： Mn promotion nickel catalysts CO₂ methanation co-methanation of CO and CO₂

HTML PDF 收藏

Fabrication of form stable NaCl-Al2O3 composite for thermal energy storage by cold sintering process

Bilyaminu Suleiman, Qinghua Yu, Yulong Ding, Yongliang Li

《化学科学与工程前沿（英文）》 2019年第13卷第4期页码 727-735 doi: 10.1007/s11705-019-1823-2

摘要： A form stable NaCl-Al O (50-50 wt-%) composite material for high temperature thermal energy storage was fabricated by cold sintering process, a process recently applied to the densification of ceramics at low temperature ˂ 300°C under uniaxial pressure in the presence of small amount of transient liquid. The fabricated composite achieved as high as 98.65% of the theoretical density. The NaCl-Al O composite also retained the chloride salt without leakage after 30 heating-cooling cycles between 750°C–850°C together with a holding period of 24 h at 850°C. X-ray diffraction measurements indicated congruent solubility of the alumina in chloride salt, excellent compatibility of NaCl with Al O , and chemical stability at high temperature. Structural analysis by scanning electron microscope also showed limited grain growth, high density, uniform NaCl distribution and clear faceted composite structure without inter-diffusion. The latent heat storage density of 252.5 J/g was obtained from simultaneous thermal analysis. Fracture strength test showed high sintered strength around 5 GPa after 50 min. The composite was found to have fair mass losses due to volatilization. Overall, cold sintering process has the potential to be an efficient, safe and cost-effective strategy for the fabrication of high temperature thermal energy storage materials.

关键词： cold sintering process composite fabrication thermal energy storage phase change materials

HTML PDF 收藏

Complete oxidation of methane on CoO-SnO catalysts

Xingfu TANG , Jiming HAO , Junhua LI ,

《环境科学与工程前沿（英文）》 2009年第3卷第3期页码 265-270 doi: 10.1007/s11783-009-0019-2

摘要： CoO-SnO hybrid oxides were prepared by the coprecipitation method and were used to oxidate methane (CH) in presence of oxygen. The CoO-SnO with a molar ratio of Co/(Co+Sn) at 0.75 exhibited the highest catalytic activity among all the CoO-SnO hybrid oxides. Experimental results showed that the catalysts were considerably stable in the CH combustion reaction, and were verified by X-ray photoelectron spectra (XPS). It was found that CoO was the active species, and SnO acted as a support or a promoting component in the CoO-SnO hybrid oxides. The surface area was not a major factor that affected catalytic activity. The hydrogen temperature-programmed reduction (H-TPR) results demonstrated that the interaction between cobalt and tin oxides accelerated the mobility of oxygen species of CoO-SnO, leading to higher catalytic activity.

关键词： Co₃O₄-SnO₂ complete oxidation methane (CH₄)

HTML PDF 收藏

Ni-Co bimetallic catalyst for CH

Xiaohong LI, Jun AI, Wenying LI, Dongxiong LI

《化学科学与工程前沿（英文）》 2010年第4卷第4期页码 476-480 doi: 10.1007/s11705-010-0512-y

摘要： A co-precipitation method was employed to prepare Ni/Al O -ZrO , Co/Al O -ZrO and Ni-Co/Al O -ZrO catalysts. Their properties were characterized by N adsorption (BET), thermogravimetric analysis TGA , temperature-programmed reduction (TPR), temperature-programmed desorption (CO -TPD), and temperature-programmed surface reaction (CH -TPSR and CO -TPSR). Ni-Co/Al O -ZrO bimetallic catalyst has good performance in the reduction of active components Ni, Co and CO adsorption. Compared with mono-metallic catalyst, bimetallic catalyst could provide more active sites and CO adsorption sites (C+ CO = 2CO) for the methane-reforming reaction, and a more appropriate force formed between active components and composite support (SMSI) for the catalytic reaction. According to the CH -CO -TPSR, there were 80.9% and 81.5% higher CH and CO conversion over Ni-Co/Al O -ZrO catalyst, and its better resistance to carbon deposition, less than 0.5% of coke after 4 h reaction, was found by TGA. The high activity and excellent anti-coking of the Ni-Co/Al O -ZrO catalyst were closely related to the synergy between Ni and Co active metal, the strong metal-support interaction and the use of composite support.

关键词： Ni-Co bimetallic catalyst composite support CH₄ reforming with CO₂

HTML PDF 收藏

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

HTML PDF 收藏

铝电解用Fe-Ni-Co-Al₂O₃金属陶瓷惰性阳极

邱竹贤,石忠宁,徐君莉

《中国工程科学》 2004年第6卷第8期页码 35-39

摘要：

研制了一种新型铝电解金属陶瓷惰性阳极，阳极基体由Fe-Ni-CoAl₂O₃构成。在石墨坩埚中，960℃温度下，电解质中的氧化铝质量分数为6.0%，摩尔比为2.6；阳极电流密度为1.0 A/cm²，阳极尺寸大小为120 mm×80 mm×，石墨阴极尺寸大小为120 mm×40 mm×20 mm，通入的直流电为100～300 A，电解时间各为10 h；实验所得的电解铝产品纯度达到98%以上，杂质主要为Fe，Ni，Co阳极的反电动势为2.45 V，比理论分解电压仅高出0.25 V证明该阳极为惰性阳极，在电解槽中进行的是Al₂O₃的分解反应。

关键词：铝电解惰性阳极反电动势

HTML PDF 收藏

ZnFe₂O₄/BiVO₄ Z-scheme heterojunction for efficient visible-light photocatalytic

《化学科学与工程前沿（英文）》 2023年第17卷第11期页码 1728-1740 doi: 10.1007/s11705-023-2322-z

摘要： A novel Z-scheme ZnFe₂O₄/BiVO₄ heterojunction photocatalyst was successfully synthesized using a convenient solvothermal method and applied in the visible light photocatalytic degradation of ciprofloxacin, which is a typical antibiotic contaminant in wastewater. The heterostructure of as-synthesized catalysts was confirmed using X-ray diffraction, scanning electron microscopy, transmission electron microscopy and X-ray photoelectron spectroscopy characterizations. Compared with the single-phase counterparts, ZnFe₂O₄/BiVO₄ demonstrated considerably enhanced photogenerated charge separation efficiencies because of the Z-scheme transfer mechanism of electrons between the composite photocatalysts. Consequently, the 30% ZnFe₂O₄/BiVO₄ catalyst afforded a degradation rate of up to 97% of 20 mg/L ciprofloxacin under 30 min of visible light irradiation with a total organic carbon removal rate of 50%, which is an excellent activity compared with ever reported BiVO₄-based catalysts. In addition, the liquid chromatography-mass spectrometry and quantitative structure-activity relationships model analyses demonstrated that the toxicity of the intermediates was lower than that of the parent ciprofloxacin. Moreover, the as-synthesized ZnFe₂O₄/BiVO₄ heterojunctions were quite stable and could be reused at least four times. This study thus provides a promising Z-scheme heterojunction photocatalyst for the efficient removal and detoxication of antibiotic pollutants from wastewater.

关键词： ZnFe₂O₄/BiVO₄ Z-scheme heterojunction photocatalytic degradation ciprofloxacin

HTML PDF 收藏

固体氧化物电解池共电解H₂O/CO₂研究进展

范慧,宋世栋,韩敏芳

《中国工程科学》 2013年第15卷第2期页码 107-112

摘要：本文介绍了固体氧化物电解池的结构特点及其用于H2O/CO2的共电解制备H2和CO的工作原理，综述了固体氧化物电解池的组成形式，以及单片电解池和电解池堆用于H2O/CO2共电解反应的国内外研究进展，并阐述了提高固体氧化物电解池共电解效率所亟需解决的问题

关键词：固体氧化物电解池 H₂O/CO₂共电解合成气电解效率水电解

HTML PDF 收藏

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

HTML PDF 收藏

标题作者时间类型操作

Ultrasound-assisted co-precipitation synthesis of mesoporous Co3O4–CeO2 composite oxides for highly selective

期刊论文

On the monolayer dispersion behavior of Co₃O₄ on HZSM-5 support: designing applicablecatalysts for selective catalytic reduction of nitrogen oxides by ammonia

期刊论文

Al₂O₃ and CeO₂-promoted MgO sorbents for CO₂ capture at moderate

Huimei Yu, Xiaoxing Wang, Zhu Shu, Mamoru Fujii, Chunshan Song

期刊论文

ZnFe₂O₄ deposited on BiOCl with exposed (001) and (010) facets for photocatalyticreduction of CO₂ in cyclohexanol

Guixian Song, Xionggang Wu, Feng Xin, Xiaohong Yin

期刊论文

Rh₂O₃/hexagonal CePO₄ nanocatalysts for N₂O decomposition

Huan Liu, Zhen Ma

期刊论文

NiCo2O4@quinone-rich N–C core–shell nanowires as composite electrode for electric double layer capacitor

期刊论文