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 608

会议视频 33

会议信息 4

年份

2023 82

2022 122

2021 78

2020 52

2019 29

2018 29

2017 27

2016 20

2015 23

2014 17

2013 23

2012 15

2011 16

2010 15

2009 20

2008 15

2007 24

2006 5

2005 4

2004 5

展开︾

关键词

3D打印 13

院士大会 9

增材制造 7

经济 5

医学 3

空间可展开结构 3

营养健康 3

2020 2

3D生物打印 2

4D打印 2

FY-3卫星 2

创新设计 2

可视化 2

工程管理 2

支架 2

组织工程 2

能源 2

风云三号 2

&alpha 1

展开︾

检索范围：

排序：展示方式：

WO₃ nanomaterials synthesized via a sol-gel method and calcination for use as a CO gas sensor

Diah SUSANTI,A.A. Gede Pradnyana DIPUTRA,Lucky TANANTA,Hariyati PURWANINGSIH,George Endri KUSUMA,Chenhao WANG,Shaoju SHIH,Yingsheng HUANG

《化学科学与工程前沿（英文）》 2014年第8卷第2期页码 179-187 doi: 10.1007/s11705-014-1431-0

摘要： Carbon monoxide is a poisonous and hazardous gas and sensitive sensor devices are needed to prevent humans from being poisoned by this gas. A CO gas sensor has been prepared from WO synthesized by a sol-gel method. The sensor chip was prepared by a spin-coating technique which deposited a thin film of WO on an alumina substrate. The chip samples were then calcined at 300, 400, 500 or 600 °C for 1 h. The sensitivities of the different sensor chips for CO gas were determined by comparing the changes in electrical resistance in the absence and presence of 50 ppm of CO gas at 200 °C. The WO calcined at 500 °C had the highest sensitivity. The sensitivity of this sensor was also measured at CO concentrations of 100 ppm and 200 ppm and at operating temperatures of 30 and 100 °C. Thermogravimetric analysis of the WO calcined at 500 °C indicated that this sample had the highest gas adsorption capacity. This preliminary research has shown that WO can serve as a CO gas sensor and that is should be further explored and developed.

关键词： WO₃ nanomaterial sol-gel calcinations CO gas sensor sensitivity

HTML PDF 收藏

Comparison of the morphology and structure of WO

Diah Susanti, Stefanus Haryo N, Hasnan Nisfu, Eko Prasetio Nugroho, Hariyati Purwaningsih, George Endri Kusuma, Shao-Ju Shih

《化学科学与工程前沿（英文）》 2012年第6卷第4期页码 371-380 doi: 10.1007/s11705-012-1215-3

摘要： Tungsten (VI) oxide (WO ) nanomaterials were synthesized by a sol-gel method using WCl and C H OH as precursors followed by calcination or hydrothermal treatment. X-Ray diffraction (XRD), scanning electron microscopy (SEM) and high resolution transmission electron microscopy (HRTEM) equipped with energy dispersive X-ray spectroscopy (EDX) were used to characterize the structure and morphology of the materials. There were significant differences between the WO materials that were calcinated and those that were subjected to a hydrothermal process. The XRD results revealed that calcination temperatures of 300°C and 400°C gave hexagonal structures and temperatures of 500°C and 600°C gave monoclinic structures. The SEM images showed that an increase in calcination temperature led to a decrease in the WO powder particle size. The TEM analysis showed that several nanoparticles agglomerated to form bigger clusters. The hydrothermal process produced hexagonal structures for holding times of 12, 16, and 20 h and monoclinic structures for a holding time of 24 h. The SEM results showed transparent rectangular particles which according to the TEM results originated from the aggregation of several nanotubes.

关键词： WO₃ nanomaterial sol-gel method calcination hydrothermal

HTML PDF 收藏

Z-scheme CdS/WO on a carbon cloth enabling effective hydrogen evolution

《能源前沿（英文）》 2021年第15卷第3期页码 678-686 doi: 10.1007/s11708-021-0768-6

摘要： Photocatalytic water splitting for hydrogen (H₂) generation is a potential strategy to solve the problem of energy crisis and environmental deterioration. However, powder-like photocatalysts are difficult to recycle, and the agglomeration of particles would affect the photocatalytic activity. Herein, a direct Z-scheme CdS/WO₃ composite photocatalyst was fabricated based on carbon cloth through a two-step process. With the support of carbon cloth, photocatalysts tend to grow uniformly for further applications. The experimental results showed that the H₂ yield of adding one piece of CdS/WO₃ composite material was 17.28 μmol/h, which was 5.5 times as compared to that of pure CdS-loaded carbon cloth material. A cycle experiment was conducted to verify the stability of the as-prepared material and the result demonstrated that the H₂ generation performance of CdS/WO₃ decreased slightly after 3 cycles. This work provides new ideas for the development of recyclable photocatalysts and has a positive significance for practical applications.

关键词： photocatalysis CdS/WO₃ carbon cloth Z-scheme hydrogen evolution

HTML PDF 收藏

Photoelectrocatalytic generation of H and S from toxic HS by using a novel BiOI/WO nanoflake array photoanode

《能源前沿（英文）》 2021年第15卷第3期页码 744-751 doi: 10.1007/s11708-021-0775-7

摘要： In this paper, a photoelectrocatalytic (PEC) recovery of toxic H₂S into H₂ and S system was proposed using a novel bismuth oxyiodide (BiOI)/ tungsten trioxide (WO₃) nano-flake arrays (NFA) photoanode. The BiOI/WO₃ NFA with a vertically aligned nanostructure were uniformly prepared on the conductive substrate via transformation of tungstate following an impregnating hydroxylation of BiI₃. Compared to pure WO₃ NFA, the BiOI/WO₃ NFA promotes a significant increase of photocurrent by 200%. Owing to the excellent stability and photoactivity of the BiOI/WO₃ NFA photoanode and I^–/

I 3 −

catalytic system, the PEC system toward splitting of H₂S totally converted S^2– into S without any polysulfide (

S x n −

) under solar-light irradiation. Moreover, H₂ was simultaneously generated at a rate of about 0.867 mL/(h·cm). The proposed PEC H₂S splitting system provides an efficient and sustainable route to recover H₂ and S.

关键词： bismuth oxyiodide (BiOI)/ tungsten trioxide (WO₃) nano-flake arrays (NFA) photoelectrocatalytic (PEC) H₂S splitting H₂ S

HTML PDF 收藏

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

HTML PDF 收藏

Cu-doped Bi/Bi₂WO₆ catalysts for efficient N₂ fixation by photocatalysis

《化学科学与工程前沿（英文）》 2023年第17卷第10期页码 1412-1422 doi: 10.1007/s11705-023-2312-1

摘要： In this paper, Cu-doped Bi₂WO₆ was synthesized via a solvothermal method and applied it in photocatalytic N₂ immobilization. Characterization results showed the presence of a small amount of metallic Bi in the photocatalyst, indicating that the synthesized photocatalyst is actually Bi/Cu-Bi₂WO₆ composite. The doped Cu had a valence state of +2 and most likely substituted the position of Bi³⁺. The introduced Cu did not affect the metallic Bi content, but mainly influenced the energy band structure of Bi₂WO₆. The band gap was slightly narrowed, the conduction band was elevated, and the work function was reduced. The reduced work function improved the transfer and separation of charge carriers, which mainly caused the increased photoactivity. The optimized NH₃ generation rates of Bi/Cu-Bi₂WO₆ reached 624 and 243 μmol·L^–1·g^–1·h^–1 under simulated solar and visible light, and these values were approximately 2.8 and 5.9 times higher those of Bi/Bi₂WO₆, respectively. This research provides a method for improving the photocatalytic N₂ fixation and may provide more information on the design and preparation of heteroatom-doped semiconductor photocatalysts for N₂-to-NH₃ conversion.

关键词： Bi₂WO₆ Cu doping work function photocatalytic N₂ fixation charge separation

HTML PDF 收藏

Pore structure of cementitious material enhanced by graphitic nanomaterial: a critical review

S.A. GHAHARI, E. GHAFARI, L. ASSI

《结构与土木工程前沿（英文）》 2018年第12卷第1期页码 137-147 doi: 10.1007/s11709-017-0431-9

摘要： Carbon nano tubes (CNT) has been introduced as an efficient nanomaterial in order to improve the mechanical and durability properties of concrete. The effect of CNT on the microstructures of cementitious materials has been widely reported. This paper combines a critical review on the effect of CNT on the pore and microstructure of cement composite with a discussion on the porosity measurement of pastes containing CNT using mercury intrusion porosimetry techniques (MIP). It was found that, surface treatment by H SO and HNO solution forms carboxyl acid groups on CNTs’ surfaces that lead to the improvement of reinforcement. In this scope, this review paper involves analyzing the effect of CNT on the microstructure and the pore structure of cementitious materials. The existing methods of measuring the porosity of cementitious material are reviewed, in particular, the contact angle measurement is discussed in detail in which the most effective parameters and possible errors of calculation is presented.

关键词： carbon nano tubes microstructure porosity mercury intrusion porosimetry cement composite

HTML PDF 收藏

Effective regeneration of thermally deactivated commercial V-W-Ti catalysts

Xuesong SHANG, Jianrong LI, Xiaowei YU, Jinsheng CHEN, Chi HE

《化学科学与工程前沿（英文）》 2012年第6卷第1期页码 38-46 doi: 10.1007/s11705-011-1167-z

摘要： An effective method for the regeneration of thermally deactivated commercial monolith SCR catalysts was investigated. Two types of regenerated solutions, namely NH Cl (1 mol/L) and dilute H SO (0.5 mol/L), were employed to treat the used catalyst. The effects of temperature and the regeneration process on the structural and textural properties of the catalysts were determined by X-ray diffraction, scanning electron microscopy, N adsorption/desorption, elemental analysis and Fourier transform infrared spectroscopy. The results suggest that the anatase phase of the used catalyst is maintained after exposure to high temperatures. Some of the catalytic activity was restored after regeneration. The catalyst regenerated by aqueous NH Cl had a higher activity than that of the catalyst treated by dilute H SO . The main reason is that the NH generated from the decomposition of NH Cl at high temperatures can be adsorbed onto the catalyst which promotes the reaction. The aggregated V O were partially re-dispersed during the regeneration process, and the intrinsic oxidation of ammonia with high concentrations of O is a factor that suppresses the catalytic activity.

关键词： V₂O₅-WO₃/TiO₂ catalysts thermal deactivation regeneration NH₄Cl dilute H₂SO₄ solution

HTML PDF 收藏

Morphology selective construction of

Maher Darwish, Ali Mohammadi, Navid Assi, Samer Abuzerr, Youssef Alahmad

《化学科学与工程前沿（英文）》 2020年第14卷第4期页码 561-578 doi: 10.1007/s11705-019-1808-1

摘要： Controlled growth of Bi WO nanorods with exposed [0 0 1] facets and the fabrication of an Fe O -Bi WO magnetic composite by a microwave-assisted polyol process, were achieved in this study. The adsorptivity and photocatalytic performance of the composite toward sunset yellow dye degradation were greatly enhanced by the -cyclodextrin cavities on its surface, firmly anchored through a cetyltrimethylammonium bromide linkage. A series of examinations and characterizations were carried out to determine the influence of various factors on the morphological modulation-photocatalytic behavior of the pure Bi WO prior to final functionalization. Changing the pH of the precursor solution impacted the formation of 0D, 2D, and 3D structures; however, the presence of hexamethylenetetramine surfactant induced the development of 1D nanorod structure. A reasonable crystal growth mechanism was proposed to elucidate the formation process. Conversely, the mechanism of the activity enhancement of -cyclodextrin functionalized Fe O -Bi WO , compared to that of the non-functionalized samples, could be realized with the assistance of chemical trapping experiments on sunset yellow, and was confirmed on the colorless antibiotic (sulfamethoxazole). The high performance and durability of this composite can be attributed to the facet-dependent activity, large adsorption capacity due to inclusion interactions, enhanced visible light absorption, and efficient charge separation.

关键词： β-cyclodextrin Bi₂WO₆ shape controlled nanorod sunset yellow

HTML PDF 收藏

Fabrication of highly efficient Bi

Wei Mao, Lixun Zhang, Tianye Wang, Yichen Bai, Yuntao Guan

《环境科学与工程前沿（英文）》 2021年第15卷第4期 doi: 10.1007/s11783-020-1344-8

摘要： Abstract • A novel Bi2WO6/CuS composite was fabricated by a facile solvothermal method. • This composite efficiently removed organic pollutants and Cr(VI) by photocatalysis. • The DOM could promoted synchronous removal of organic pollutants and Cr(VI). • This composite could be applied at a wide pH range in photocatalytic reactions. • Possible photocatalytic mechanisms of organic pollutants and Cr(VI) were proposed. A visible-light-driven Bi2WO6/CuS p-n heterojunction was fabricated using an easy solvothermal method. The Bi2WO6/CuS exhibited high photocatalytic activity in a mixed system containing rhodamine B (RhB), tetracycline hydrochloride (TCH), and Cr (VI) under natural conditions. Approximately 98.8% of the RhB (10 mg/L), 87.6% of the TCH (10 mg/L) and 95.1% of the Cr(VI) (15 mg/L) were simultaneously removed from a mixed solution within 105 min. The removal efficiencies of TCH and Cr(VI) increased by 12.9% and 20.4%, respectively, in the mixed solution, compared with the single solutions. This is mainly ascribed to the simultaneous consumption electrons and holes, which increases the amount of excited electrons/holes and enhances the separation efficiency of photogenerated electrons and holes. Bi2WO6/CuS can be applied over a wide pH range (2–6) with strong photocatalytic activity for RhB, TCH and Cr(VI). Coexisiting dissolved organic matter in the solution significantly promoted the removal of TCH (from 74.7% to 87.2%) and Cr(VI) (from 75.7% to 99.9%) because it accelerated the separation of electrons and holes by consuming holes as an electron acceptor. Removal mechanisms of RhB, TCH, and Cr(VI) were proposed, Bi2WO6/CuS was formed into a p-n heterojunction to efficiently separate and transfer photoelectrons and holes so as to drive photocatalytic reactions. Specifically, when reducing pollutants (e.g., TCH) and oxidizing pollutants (e.g., Cr(VI)) coexist in wastewater, the p-n heterojunction in Bi2WO6/CuS acts as a “bridge” to shorten the electron transport and thus simultaneously increase the removal efficiencies of both types of pollutants.

关键词： Photocatalysis Bi₂WO₆/CuS Organic pollutants Cr(VI) Synergistic effect

HTML PDF 收藏

Recent progress in MoS

Soheil RASHIDI, Akshay CARINGULA, Andy NGUYEN, Ijeoma OBI, Chioma OBI, Wei WEI

《能源前沿（英文）》 2019年第13卷第2期页码 251-268 doi: 10.1007/s11708-019-0625-z

摘要： In an era of graphene-based nanomaterials as the most widely studied two-dimensional (2D) materials for enhanced performance of devices and systems in solar energy conversion applications, molybdenum disulfide (MoS ) stands out as a promising alternative 2D material with excellent properties. This review first examined various methods for MoS synthesis. It, then, summarized the unique structure and properties of MoS nanosheets. Finally, it presented the latest advances in the use of MoS nanosheets for important solar energy applications, including solar thermal water purification, photocatalytic process, and photoelectrocatalytic process.

关键词： 2D nanomaterial molybdenum disulfide solar energy conversion solar thermal conversion photocatalytst photoelectrocatalyst

HTML PDF 收藏

Review of recent developments in cement composites reinforced with fibers and nanomaterials

Jianzhuang XIAO, Nv HAN, Yan LI, Zhongsen ZHANG, Surendra P. SHAH

《结构与土木工程前沿（英文）》 2021年第15卷第1期页码 1-19 doi: 10.1007/s11709-021-0723-y

摘要： The quest for high-performance construction materials is led by the development and application of new reinforcement materials for cement composites. Concrete reinforcement with fibers has a long history. Nowadays, many new fibers associated with high performance and possessing eco-environmental characteristics, such as basalt fibers and plant fibers, have received much attention from researchers. In addition, nanomaterials are considered as a core material in the modification of cement composites, specifically in the enhancement of the strength and durability of composites. This paper provides an overview of the recent research progress on cement composites reinforced with fibers and nanomaterials. The influences of fibers and nanomaterials on the fresh and hardened properties of cement composites are summarized. Moreover, future trends in the application of these fibers or of nanomaterial-reinforced cement composites are proposed.

关键词： cement composites fiber nanomaterial mechanical property durability

HTML PDF 收藏

Effective degradation of tetracycline by mesoporous Bi

Xiaolong CHU,Guoqiang SHAN,Chun CHANG,Yu FU,Longfei YUE,Lingyan ZHU

《环境科学与工程前沿（英文）》 2016年第10卷第2期页码 211-218 doi: 10.1007/s11783-014-0753-y

摘要： Bi WO was synthesized with a hydrothermal method at different pHs and used for the degradation of tetracycline (TC) in water. The mesoporous Bi WO prepared at pH 1 (BWO-1) displayed the highest adsorption and degradation capacity to TC due to its large surface area and more efficient capacity to separate photogenerated electrons and holes. 97% of TC at 20 mg·L was removed by BWO-1 at 0.5 g·L after 120 min irradiation under simulated solar light. Only 31% of the total organic carbon (TOC) was removed after 360 min irradiation although the TC removal reached 100%, suggesting that TC was mainly transformed to intermediate products rather than completely mineralized. The intermediates were identified by high-performance liquid chromatography-time of flight-mass spectrometry (HPLC-TOF-MS) and possible photodegradation pathways were proposed.

关键词： Bi₂WO₆ hydrothermal synthesis tetracycline (TC) photocatalysis

HTML PDF 收藏

虞晓含：中医话健康，食补改善免疫力（2020年3月1日）

2022年04月18日

关键词：营养健康

Facile synthesis of hierarchical flower-like Ag/Cu

Mengyun Wang, Shengbo Zhang, Mei Li, Aiguo Han, Xinli Zhu, Qingfeng Ge, Jinyu Han, Hua Wang

《化学科学与工程前沿（英文）》 2020年第14卷第5期页码 813-823 doi: 10.1007/s11705-019-1854-8

摘要： Novel, hierarchical, flower-like Ag/Cu O and Au/Cu O nanostructures were successfully fabricated and applied as efficient electrocatalysts for the electrochemical reduction of CO . Cu O nanospheres with a uniform size of ~180 nm were initially synthesized. Thereafter, Cu O was used as a sacrificial template to prepare a series of Ag/Cu O composites through galvanic replacement. By varying the Ag/Cu atomic ratio, Ag /Cu O, having a hierarchical, flower-like nanostructure with intersecting Ag nanoflakes encompassing an inner Cu O sphere, was prepared. The as-prepared Ag /Cu O samples presented higher Faradaic efficiencies (FE) for CO and relatively suppressed H evolution than the parent Cu O nanospheres due to the combination of Ag with Cu O in the former. Notably, the highest CO evolution rate was achieved with Ag /Cu O due to the larger electroactive surface area furnished by the hierarchical structure. The same hierarchical flower-like structure was also obtained for the Au /Cu O composite, where the FE (10%) was even higher than that of Ag /Cu O. Importantly, the results reveal that Ag /Cu O and Au /Cu O both exhibit remarkably improved stability relative to Cu O. This study presents a facile method of developing hierarchical metal-oxide composites as efficient and stable electrocatalysts for the electrochemical reduction of CO .

关键词： bimetallic nanostructure hierarchical metal/oxide nanomaterial galvanic replacement electrochemical reduction of CO₂