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 1206

会议视频 27

会议信息 4

年份

2024 2

2023 178

2022 189

2021 200

2020 106

2019 52

2018 29

2017 57

2016 35

2015 49

2014 46

2013 43

2012 21

2011 27

2010 46

2009 33

2008 23

2007 45

2006 5

2005 2

展开︾

关键词

SARS-CoV-2 7

COVID-19 5

微波散射计 5

碳中和 5

Cu(In 4

HY-2 4

2019 3

2型糖尿病 3

GPS 3

Ga)Se₂ 3

HY-2 卫星 3

HY-2A卫星 3

代谢与免疫 3

光催化 3

工程管理 3

微波辐射计 3

营养健康 3

4D打印 2

CCS 2

展开︾

检索范围：

排序：展示方式：

Stability of Ni/SiO

Bettina Stolze,Juliane Titus,Stephan A. Schunk,Andrian Milanov,Ekkehard Schwab,Roger Gläser

《化学科学与工程前沿（英文）》 2016年第10卷第2期页码 281-293 doi: 10.1007/s11705-016-1568-0

摘要： Ni/SiO -ZrO catalysts with Ni loadings of 1 to 13 wt-% were prepared, characterized by elemental analysis, X-ray diffraction, N sorption, temperature programmed oxidation, temperature programmed reduction, and tested for their activity and stability in the dry reforming of methane with carbon dioxide at 850 °C, gas hourly space velocity of 6000 and 1800 h and atmospheric pressure. The SiO -ZrO support as obtained through a simple and efficient sol-gel synthesis is highly porous ( = 90 m ·g , = 4.4 nm) with a homogeneously distributed Si-content of 3 wt-%. No loss of Si or formation of monoclinic ZrO , even after steaming at 850 °C for 160 h, was detectable. The catalyst with 5 wt-% Ni loading in its fully reduced state is stable over 15?h on-stream in the dry reforming reaction. If the catalyst was not fully reduced, a reduction during the early stages of dry reforming is accompanied by the deposition of up to 44 mg·g carbon as shown by experiments in a magnetic suspension balance. Rapid coking occurs for increased residence times and times-on-stream starting at 50 h. The Ni loading of 5 wt-% on SiO -ZrO was shown to provide an optimal balance between activity and coking tendency.

关键词： Ni/SiO₂-ZrO₂ synthesis gas dry reforming coking steaming

HTML PDF 收藏

Preparation of Ni/SiO catalyst in ionic liquids for hydrogenation

FAN Qingming, LIU Yingxin, ZHENG Yifan, YAN Wei

《化学科学与工程前沿（英文）》 2008年第2卷第1期页码 63-68 doi: 10.1007/s11705-008-0013-4

摘要： A series of silica supported nickel catalysts were prepared from nickel nitrate and tetraethyl orthosilicate by the sol-gel method with the imidazolium type ionic liquids as solvents. The catalysts were characterized by means of X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). Their catalytic performances for the selective hydrogenation of cinnamaldehyde to hydrocinnamaldehyde were investigated. The results show that the Ni/SiO catalyst prepared with 1-(2-hydroxyethyl)-3-methyl-imidazole tetrafluoroborate ionic liquid as solvent exhibits the highest catalytic activity for the reaction. Under the optimal conditions of catalyst dosage (based on the mass of cinnamaldehyde used) 10%, reaction pressure 2 MPa, temperature 373 K and reaction time 2 h, the conversion of cinnamaldehyde and the selectivity to hydrocinnamaldehyde can reach 97.6% and 98.8%, respectively.

关键词： dispersive conversion catalytic 2-hydroxyethyl catalytic activity

HTML PDF 收藏

The stabilization effect of Al₂O₃ on unconventional Pb/SiO₂ catalyst

《化学科学与工程前沿（英文）》 2023年第17卷第10期页码 1423-1429 doi: 10.1007/s11705-023-2315-y

摘要： Similar to Sn, Pb located at the same group (IVA) in the periodic table of elements, can also catalyze propane dehydrogenation to propene, while a fast deactivation can be observed. To enhance the stability, the traditional carrier Al₂O₃ with a small amount, was introduced into Pb/SiO₂ catalyst in this study. It has been proved that Al₂O₃ can inhibit the reduction of PbO, and weaken the agglomeration and loss of Pb species due to its enhanced interaction with Pb species. As a result, 3Al15Pb/SiO₂ catalyst exhibits a much higher stability up to more than 150 h. In addition, a simple schematic diagram of the change of surface species on the catalyst surface after Al₂O₃ addition was also proposed.

关键词： Pb/SiO₂ Al₂O₃ propane dehydrogenation propene stability

HTML PDF 收藏

电沉积Zn-Fe-SiO2复合镀层研究

张英杰,范云鹰,董鹏,罗少林

《中国工程科学》 2008年第10卷第3期页码 93-96

摘要：

报告了电沉积Zn-Fe-SiO2复合镀层的研究结果，论述了电流密度、极间距、搅拌方式、阳极数量及排布方式、添加剂等对Zn-Fe-SiO2复合镀层的影响及试验所取得的技术指标试验结果表明，Zn-Fe-SiO2复合镀层工艺具有过程稳定性好，维护措施简单方便，生产的环保及安全性好等优点。

关键词：电沉积复合镀层 Zn-Fe-SiO2

HTML PDF 收藏

A simple and cheap method for preparation of coupled ZrO2/ZnO with high photocatalytic activities

WANG Zheng, ZHANG Bingru, LI Fengting

《环境科学与工程前沿（英文）》 2007年第1卷第4期页码 454-458 doi: 10.1007/s11783-007-0072-7

摘要： The objective of this study was to prepare a new photocatalyst with high activities for degradation of organic pollutants. Coupled ZrO/ZnO photocatalyst was prepared with a simple precipitation method with cheap raw

关键词： objective ZrO/ZnO photocatalyst photocatalyst precipitation degradation

HTML PDF 收藏

Enhanced performance of oxygen vacancies on CO adsorption and activation over different phases of ZrO

《能源前沿（英文）》 2023年第17卷第4期页码 545-554 doi: 10.1007/s11708-023-0867-7

摘要： The effect of oxygen vacancies on the adsorption and activation of CO₂ on the surface of different phases of ZrO₂ is investigated by density functional theory (DFT) calculations. The calculations show that the oxygen vacancies contribute greatly to both the adsorption and activation of CO₂. The adsorption energy of CO₂ on the c-ZrO₂, t-ZrO₂ and, m-ZrO₂ surfaces is enhanced to 5, 4, and 3 folds with the help of oxygen vacancies, respectively. Moreover, the energy barrier of CO₂ dissociation on the defective surfaces of c-ZrO₂, t-ZrO₂, and m-ZrO₂ is reduced to 1/2, 1/4, and 1/5 of the perfect surface with the assistance of oxygen vacancies. Furthermore, the activation of CO₂ on the ZrO₂ surface where oxygen vacancies are present, and changes from an endothermic reaction to an exothermic reaction. This finding demonstrates that the presence of oxygen vacancies promotes the activation of CO₂ both kinetically and thermodynamically. These results could provide guidance for the high-efficient utilization of CO₂ at an atomic scale.

关键词： CO₂ activation oxygen vacancies ZrO₂ different phases

HTML PDF 收藏

Preparation and characterization of nanocrystalline ZrO2-7%Y2O3 powders for thermal barrier coatings

Kirsten BOBZIN, Lidong ZHAO, Thomas SCHLAEFER, Thomas WARDA

《机械工程前沿（英文）》 2011年第6卷第2期页码 176-181 doi: 10.1007/s11465-011-0220-4

摘要：

High-energy ball milling is an effective method to produce nanocrystalline oxides. In this study, a conventional ZrO₂-7%Y₂O₃spray powder was ball-milled to produce nanocrystalline powders with high levels of crystalline disorders for deposition of thermal barrier coatings. The powder was milled both with 100Cr6 steel balls and with ZrO₂-3%Y₂O₃ ceramic balls as grinding media. The milling time was varied in order to investigate the effect of the milling time on the crystallite size. The powders were investigated in terms of their crystallite sizes and morphologies by X-ray diffraction analysis (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results show that under given milling conditions the powder was already nanostructured after 40 min milling. The crystallite size decreased significantly with increasing milling time within first 120 min. After that, a further increase of milling time did not lead to a significant reduction of the crystallite size. Ball-milling led to lattice microstrains. Milling with the steel balls resulted in finer nano-sized crystal grains, but caused the contamination of the powder. The nano-sized crystal grains coarsened during the heat-treatment at 1250°C.

关键词： nanostrucured powders yttria stabilized zirconia (YSZ) high-energy ball milling thermal barrier coatings

HTML PDF 收藏

Visbreaking of heavy petroleum oil catalyzed by SO/ZrO solid super-acid doped with Ni or Sn

JING Ping, LI Qingbiao, HAN Mei, SUN Daohua, JIA Lishan, FANG Weiping

《化学科学与工程前沿（英文）》 2008年第2卷第2期页码 186-190 doi: 10.1007/s11705-008-0035-y

摘要： SO/ZrO solid super-acid catalysts (SZ) doped with Ni or Sn (Ni/SZ, Sn/SZ) were prepared for catalytic visbreaking of heavy petroleum oil from Shengli oil field. The visbreaking reactions were carried out at 240°C and 3–4 MPa for 24 h using a heavy petroleum oil to catalyst mass ratio of 100 : 0.05. The effect of water content on viscosity of heavy petroleum oil was also investigated. Both catalysts can promote thermolysis of heavy petroleum oil and the viscosity was reduced from 0.319 Pa·s to 0.135 Pa·s for Ni/SZ and 0.163 Pa·s for (Sn/SZ) with visbreaking rates of 57.7% and 48.9%, respectively. After visbreaking, the saturated hydrocarbon content increased while aromatics, resin, asphaltene, sulfur and nitrogen content decreased. The presence of water was disadvantageous to visbreaking of heavy petroleum oil.

关键词： thermolysis Shengli asphaltene SO/ZrO presence

HTML PDF 收藏

Comparison study on strategies to prepare nanocrystalline Li

Qiang XIAO, Xiaodan TANG, Yefeng LIU, Yijun ZHONG, Weidong ZHU

《化学科学与工程前沿（英文）》 2013年第7卷第3期页码 297-302 doi: 10.1007/s11705-013-1346-1

摘要： A comparison study has been conducted on the strategies for synthesizing nanocrystalline Li ZrO and K-doped Li ZrO absorbents for CO capture at high temperatures, including solid-state and liquid-phase methods, citrate route, and starch-assisted sol-gel method combined with freeze-drying technique. The absorption properties, including uptake rate and absorption capacity, of synthesized absorbents were investigated by thermogravimetric analysis (TGA) at different CO partial pressures. The nanosized Li ZrO crystals synthesized by the citrate route exhibit a faster uptake and a higher, nearly stoichiometric absorption capacity than those synthesized by the solid-state and liquid-phase methods. The doping of K into Li ZrO can significantly improve the uptake rate of CO , especially at low CO partial pressures. For the synthesis of K-doped Li ZrO , the citrate route has poor reproducibility and scalability, whereas the starch-assisted sol-gel method combined with freeze-drying technique is reproducible and easily scaled up, and the thus synthesized absorbents possess excellent CO capture properties.

关键词： CO₂ capture Li₂ZrO₃ K-doped Li₂ZrO₃ citrate starch freeze-drying technique

HTML PDF 收藏

Hydrogenation of furfuryl alcohol to tetrahydrofurfuryl alcohol on NiB/SiO2 amorphous alloy catalyst

SONG Yun, LI Wei, ZHANG Minghui, TAO Keyi

《化学科学与工程前沿（英文）》 2007年第1卷第2期页码 151-154 doi: 10.1007/s11705-007-0028-2

摘要： NiB/SiO amorphous alloy catalyst was prepared by power electroless plating method and characterized by induction coupled plasma (ICP), Brunauer Emmett Teller method (BET), transmission electron microscope (TEM) and X-ray diffraction (XRD) techniques. The catalytic performance of NiB/SiO was investigated for the hydrogenation of furfuryl alcohol (FA) to tetrahydrofurfuryl alcohol (THFA). The effects of operational conditions, such as reaction temperature, pressure, and stirring rate were carefully studied. The proper conditions were determined as the following: pressure 2.0 MPa, temperature 120?C and stirring rate 550 r/min. A typical result with FA conversion of 99% and THFA selectivity of 100% was obtained under such conditions, which was close to that over Raney Ni.

关键词： following Brunauer electroless temperature transmission

HTML PDF 收藏

SiO₂ passivation layer grown by liquid phase deposition for silicon solar cell application

Yanlin CHEN,Sihua ZHONG,Miao TAN,Wenzhong SHEN

《能源前沿（英文）》 2017年第11卷第1期页码 52-59 doi: 10.1007/s11708-016-0429-3

摘要： Surface passivation is one of the primary requirements for high efficient silicon solar cells. Though the current existed passivation techniques are effective, expensive equipments are required. In this paper, a comprehensive understanding of the SiO passivation layer grown by liquid phase deposition (LPD) was presented, which was cost-effective and very simple. It was found that the post-annealing process could significantly enhance the passivation effect of the LPD SiO film. Besides, it was revealed that both chemical passivation and field-effect passivation mechanisms played important roles in outstanding passivation effect of the LPD SiO film through analyzing the minority carrier lifetime and the surface recombination velocity of n-type and p-type silicon wafers. Although the deposition parameters had little influence on the passivation effect, they affected the deposition rate. Therefore, appropriate deposition parameters should be carefully chosen based on the compromise of the deposition rate and fabrication cost. By utilizing the LPD SiO film as surface passivation layer, a 19.5%-efficient silicon solar cell on a large-scale wafer (156 mm × 156 mm) was fabricated.

关键词： Si solar cell passivation SiO₂ liquid phase deposition carrier lifetime

HTML PDF 收藏

Preparation and rheological behaviors of PA6/SiO2 nanocompiste

WEI Shanshan, LIU Yuejun, LI Xianggang, HUANG Yugang, WANG Xiayu, ZHANG Ping

《化学科学与工程前沿（英文）》 2007年第1卷第4期页码 332-337 doi: 10.1007/s11705-007-0060-2

摘要： The polyamide 6 (PA6)/SiO nanocomposites were prepared by in situ polymerization and the rheological behaviors were investigated. The morphology of resultant materials was characterized by scanning electron microscopy (SEM) and the rheological behaviors were characterized by capillary rheometer. The results showed that the SiO particle size was around 50 nm and the particles dispersed evenly in PA6 matrix. The nanocomposites were pesudoplastic fluids and the apparent viscosities of nanocomposites increased initially and then decreased with the increase in nano-SiO content at the same temperature. The non-Newtonian indexes of nanocomposites were smaller than those of pure PA6. With the increase in nano-SiO content the apparent viscous activation energies of nanocomposites increased initially and then decreased. The rheological behaviors revealed that there were strong interactions between PA6 macromolecule chains and nano-SiO particles.

关键词： polyamide temperature rheological activation pesudoplastic

HTML PDF 收藏

一种提高超疏水木材机械稳定性的方法

王成毓,刘峰

《中国工程科学》 2014年第16卷第4期页码 79-82

摘要：本文将聚乙烯醇（PVA）与二氧化硅（SiO₂）复合，通过滴涂法在木材表面形成一层有机-无机复合薄膜，之后对薄膜进行疏水改性，制得了一种机械稳健性较好的超疏水木材。

关键词：超疏水机械稳定性 PVA/SiO2 木材表面

HTML PDF 收藏

超疏水SiO2/PS 薄膜于木材表面的构建

张明,王成毓

《中国工程科学》 2014年第16卷第4期页码 83-86

摘要：

通过溶胶-凝胶法一步合成疏水性且具备独特形貌的二氧化硅粒子，联合聚苯乙烯以滴涂的方式于木材表面仿生合成了稳定性超疏水薄膜。经处理后的木材表面与水的静态接触角为153°，滚动角小于5°。通过扫描电子显微镜照片观察到该复合涂层拥有微米/亚微米的二维等级粗糙结构，该结构协同低表面能物质共同决定超疏水性木材的成功制得。此外，进一步研究了超疏水性木材表面的稳定性和耐久性。结果表明，该超疏水性木材于水、腐蚀性液体（酸液/碱液）、常见有机溶剂中以及一些常见条件下仍保留超疏水特性，为未来木材材料的应用领域扩展提供了有利条件。

关键词：超疏水木材表面滴涂法复合薄膜

HTML PDF 收藏

Preparation of Cu/ZrO

Xinmei LIU, Shaofen BAI, Huidong ZHUANG, Zifeng YAN

《化学科学与工程前沿（英文）》 2012年第6卷第1期页码 47-52 doi: 10.1007/s11705-011-1170-4

摘要： Cu/ZrO catalysts for methanol synthesis from CO /H were respectively prepared by deposition coprecipitation (DP) and solid state reaction (SR) methods. There is an intimate interaction between copper and zirconia, which strongly affects the reduction property and catalytic performance of the catalysts. The stronger the interaction, the lower the reduction temperature and the better the performance of the catalysts. Surface area, pore structure and crystal structure of the catalysts are mainly controlled by preparation methods and alkalinity of synthesis system. The conversion of CO and selectivity of methanol are higher for DP catalysts than for SP catalysts.

关键词： Cu/ZrO₂ methanol synthesis deposition coprecipitation solid state reaction CO₂/H₂