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 1325

会议视频 25

会议信息 5

年份

2024 3

2023 171

2022 182

2021 211

2020 118

2019 72

2018 47

2017 70

2016 51

2015 54

2014 59

2013 57

2012 28

2011 28

2010 53

2009 40

2008 22

2007 38

2006 3

2005 3

展开︾

关键词

SARS-CoV-2 7

微波散射计 5

碳中和 5

COVID-19 4

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

CCS 2

CO₂利用 2

展开︾

检索范围：

排序：展示方式：

Core designing of a new type of TVS-2M FAs: neutronics and thermal-hydraulics design basis limits

Saeed GHAEMI, Farshad FAGHIHI

《能源前沿（英文）》 2021年第15卷第1期页码 256-278 doi: 10.1007/s11708-018-0583-x

摘要： One of the most important aims of this study is to improve the core of the current VVER reactors to achieve more burn-up (or more cycle length) and more intrinsic safety. It is an independent study on the Russian new proposed FAs, called TVS-2M, which would be applied for the future advanced VVERs. Some important aspects of neutronics as well as thermal hydraulics investigations (and analysis) of the new type of Fas are conducted, and results are compared with the standards PWR CDBL. The TVS-2M FA contains gadolinium-oxide which is mixed with UO (for different Gd densities and U-235 enrichments which are given herein), but the core does not contain BARs. The new type TVS-2M Fas are modeled by the SARCS software package to find the PMAXS format for three states of CZP and HZP as well as HFP, and then the whole core is simulated by the PARCS code to investigate transient conditions. In addition, the WIMS-D5 code is suggested for steady core modeling including TVS-2M FAs and/or TVS FAs. Many neutronics aspects such as the first cycle length (first cycle burn up in terms of MW d/kgU), the critical concentration of boric acid at the BOC as well as the cycle length, the axial, and radial power peaking factors, differential and integral worthy of the most reactive CPS-CRs, reactivity coefficients of the fuel, moderator, boric acid, and the under-moderation estimation of the core are conducted and benchmarked with the PWR CDBL. Specifically, the burn-up calculations indicate that the 45.6 d increase of the first cycle length (which corresponds to 1.18 MW d/kgU increase of burn-up) is the best improving aim of the new FA type called TVS-2M. Moreover, thermal-hydraulics core design criteria such as MDNBR (based on W3 correlation) and the maximum of fuel and clad temperatures (radially and axially), are investigated, and discussed based on the CDBL.

关键词： TVS-2M FAs core design basis limits VVER-1000 analysis mixture of uranium-gadolinium oxides fuels thermal-hydraulics PARCS WIMS-D5

HTML PDF 收藏

Improvement potential of today’s WEEE recycling performance: The case of LCD TVs in Belgium

Paul Vanegas, Jef R. Peeters, Dirk Cattrysse, Wim Dewulf, Joost R. Duflou

《环境科学与工程前沿（英文）》 2017年第11卷第5期 doi: 10.1007/s11783-017-1000-0

摘要： Waste of electrical and electronic equipment (WEEE) constitutes one of the most relevant waste streams because of the quantity and presence of valuable materials. However, there is limited knowledge on the resource potential of urban mining WEEE, as data on material composition, and the efficiency of current recycling treatments are still scarce. In this article, an evaluation of the recycling performance at a national level for one of the fastest growing e-waste streams: LCD TVs is carried out through the following four steps. Firstly, material characterisation is performed by means of sampling of the waste stream. Secondly, a material flow analysis is conducted by evaluating the separation performance of a recycling plant in Belgium. Thirdly, the recovered economic value and avoided environmental impact (EI) of the analysed recycling system is assessed. Finally, the potential of urban mining for Belgium is forecasted. The analysis shows that while recycling performance for ferrous metals and aluminium are relatively high; there is substantial room to better close the material loops for precious metals (PM) and plastics. PMs and plastics account for 66 % of the economic value in LCD TVs and 57% of the EI. With the current, commonly applied recycling technology only one-third of the PM and housing plastics are recycled; meaning that for these materials, at a national level for Belgium, there is a potential for improvement that represents 3.3 million euros in 2016 and 6.8 million euros in 2025.

关键词： Recycling Waste of electrical and electronic equipment (WEEE) Material flow analysis LCD TVs Precious metals Plastics

HTML PDF 收藏

Inhibition of NF-kappa B can enhance Fas-mediated apoptosis in leukemia cell line HL-60

Li WANG, Shi ZHAO, Hong-Xiang WANG, Ping ZOU

《医学前沿（英文）》 2010年第4卷第3期页码 323-328 doi: 10.1007/s11684-010-0026-5

摘要： This study explored the effects of nuclear factor-kappa B (NF-κB) inhibitor Bay 11-7082 on Fas/FasL system and Fas-mediated apoptosis in cell line HL-60 cells. The mRNA and protein levels of Fas, FasL, and X-linked inhibitor of apoptosis protein (XIAP) were detected by reverse transcription-polymerase chain reaction (RT-PCR) and flow cytometry (FCM); the level of sFasL was evaluated by enzyme-linked immunosorbent assay (ELISA); and apoptosis was determined by FCM. After treatment with Bay 11-7082, the mRNA and protein levels of FasL and XIAP in HL-60 cells were significantly lower than in the controls ( <0.05), but the mRNA and protein levels of Fas and sFasL did not change significantly ( >0.05). Apoptotic rate of HL-60 cells treated with Bay 11-7082 was significantly higher than in the controls ( <0.05). Therefore, we conclude that Bay 11-7082 can enhance Fas-mediated apoptosis in HL-60 cells by downregulating FasL and XIAP levels.

关键词： nuclear factor-kappa B Fas/FasL system HL-60 Bay 11-7082

HTML PDF 收藏

Effect of TiO

Navid Azizi, Mojgan Isanejad, Toraj Mohammadi, Reza M. Behbahani

《化学科学与工程前沿（英文）》 2019年第13卷第3期页码 517-530 doi: 10.1007/s11705-018-1781-0

摘要： Membranes have attracted much attention as economical methods for industrial chemical processes. The effects of the titanium dioxide nanoparticle load on the morphology and CO /CH separation performance of poly (ether-block-amide) (PEBAX-1657) mixed matrix membranes (MMMs) were investigated from pressures of 3–12 bar and temperatures of 30°C–60°C. The PEBAX membranes were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, thermal gravimetric analysis, atomic force microscopy and tensile strength analysis. The incorporation of TiO nanoparticles into the polymeric MMMs improved the CO /CH gas separation performance (both the permeability and selectivity) of the membranes. The CO permeability and ideal CO /CH selectivity values of the nanocomposite membrane loaded with 8 wt-% TiO were 172.32 Barrer and 24.79, respectively whereas those of the neat membrane were 129.87 Barrer and 21.39, respectively.

关键词： mixed matrix membrane TiO₂ nanoparticles PEBAX-1657 CO₂/CH₄ separation

HTML PDF 收藏

An investigation of reaction furnace temperatures and sulfur recovery

ASADI, M. PAKIZEH, M. POURAFSHARI CHENAR

《化学科学与工程前沿（英文）》 2011年第5卷第3期页码 362-371 doi: 10.1007/s11705-011-1106-z

摘要： In a modern day sulfur recovery unit (SRU), hydrogen sulfide (H S) is converted to elemental sulfur using a modified Claus unit. A process simulator called TSWEET has been used to consider the Claus process. The effect of the H S concentration, the H S/CO ratio, the input air flow rate, the acid gas flow of the acid gas (AG) splitter and the temperature of the acid gas feed at three different oxygen concentrations (in the air input) on the main burner temperature have been studied. Also the effects of the tail gas ratio and the catalytic bed type on the sulfur recovery were studied. The bed temperatures were optimized in order to enhance the sulfur recovery for a given acid gas feed and air input. Initially when the fraction of AG splitter flow to the main burner was increased, the temperature of the main burner increased to a maximum but then decreased sharply when the flow fraction was further increased; this was true for all three concentrations of oxygen. However, if three other parameters (the concentration of H S, the ratio H S/CO and the flow rate of air) were increased, the temperature of the main burner increased monotonically. This increase had different slopes depending on the oxygen concentration in the input air. But, by increasing the temperature of the acid gas feed, the temperature of the main burner decreased. In general, the concentration of oxygen in the input air into the Claus unit had little effect on the temperature of the main burner (This is true for all parameters). The optimal catalytic bed temperature, tail gas ratio and type of catalytic bed were also determined and these conditions are a minimum temperature of 300°C, a ratio of 2.0 and a hydrolysing Claus bed.

关键词： Claus unit concentration of H₂S tail gas ratio sulfur recovery catalytic bed

HTML PDF 收藏

Events and reaction mechanisms during the synthesis of an Al

M. ABDELLAHI, M. ZAKERI, H. BAHMANPOUR

《化学科学与工程前沿（英文）》 2013年第7卷第2期页码 123-129 doi: 10.1007/s11705-013-1325-6

摘要： An Al O -TiB nanocomposite was successfully synthesized by the high energy ball milling of Al, B O and TiO . The structures of the powdered particles formed at different milling times were evaluated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Thermodynamic calculations showed that the composite formed in two steps via highly exothermic mechanically induced self-sustaining reactions (MSRs). The composite started to form at milling times of 9–10 h but the reaction was not complete. The remaining starting materials were consumed by increasing the milling time to 15 h. The XRD patterns of the annealed powders showed that aluminum borate is one of the intermediate products and that it is consumed at higher temperatures. Heat treatment of the 6-h milled sample at 1100 C led to a complete formation of the composite. Increasing the milling time to 15 h led to a refining of the crystallite sizes. A nanocomposite powder with a mean crystallite size of 35–40 nm was obtained after milling for 15 h.

关键词： ball milling nanocomposite Al₂O₃ TiB₂

HTML PDF 收藏

Al₂O₃-M_xO_y硬面陶瓷涂层的喷焊制备及性能研究

王飚,王宇栋,李慧玲,张自华

《中国工程科学》 2002年第4卷第9期页码 75-80

摘要：

在碳钢母材上，用氧乙炔焰喷焊镍包铝合金粉末制取预涂层，喷焊50% Al₂O₃+50% Ni的复合粉末制取过渡层，用等离子喷焊Al₂O₃ - M_xO_y复合粉末制取最终涂层。

关键词： Al₂O₃-M_xO_y 涂层等离子抗腐蚀抗磨损

HTML PDF 收藏

Emission components characteristics of a bi-fuel vehicle at idling condition

Sameh M. METWALLEY, Shawki A. ABOUEL-SEOUD, Abdelfattah M. FARAHAT

《能源前沿（英文）》 2011年第5卷第3期页码 322-329 doi: 10.1007/s11708-011-0158-6

摘要： Natural gas (NG) represents today a promising alternative to conventional fuels for road vehicles propulsion, since it is characterized by a relatively low cost, better geopolitical distribution than oil, and lower environmental impact. This explains the current spreading of compressed natural gas (CNG) fuelled spark ignition (SI) engine, above all in the bi-fuel version, which is able to run either with gasoline or with NG. However, the aim of the present investigation is to evaluate the emission characteristics at idling condition. The vehicle engine was converted to bi-fueling system from a gasoline engine, and operated separately either with gasoline or CNG. Two different fuel injection systems (i.e., multi-point injection (MPI)-sequential and closed-loop venturi-continuous) are used, and their influences on the formation of emissions at different operating conditions are examined. A detailed comparative analysis of the engine exhaust emissions using gasoline and CNG is made. The results indicate that the CNG shows low air index and lower emissions of carbon monoxide (CO), carbon dioxide (CO ), and total hydrocarbon (THC) compared to gasoline.

关键词： road vehicle engine fuel injection systems carbon monoxide (CO) carbon dioxide (CO₂) total hydrocarbon (THC) vehicle idle conditions air index

HTML PDF 收藏

Mercury removal from aqueous solution using petal-like MoS₂

Ragini Pirarath, Palani Shivashanmugam, Asad Syed, Abdallah M.

《环境科学与工程前沿（英文）》 2021年第15卷第1期 doi: 10.1007/s11783-020-1307-0

摘要： Abstract • Synthesized few-layered MoS2 nanosheets via surfactant-assisted hydrothermal method. • Synthesized MoS2 nanosheets show petal-like morphology. • Adsorbent showed 93% of mercury removal efficiency. • The adsorption of mercury is attributed to negative zeta potential (-21.8 mV). Recently, different nanomaterial-based adsorbents have received greater attention for the removal of environmental pollutants, specifically heavy metals from aqueous media. In this work, we synthesized few-layered MoS2 nanosheets via a surfactant-assisted hydrothermal method and utilized them as an efficient adsorbent for the removal of mercury from aqueous media. The synthesized MoS2 nanosheets showed petal-like morphology as confirmed by scanning electron microscope and high-resolution transmission electron microscopic analysis. The average thickness of the nanosheets is found to be about 57 nm. Possessing high stability and negative zeta potential makes this material suitable for efficient adsorption of mercury from aqueous media. The adsorption efficiency of the adsorbent was investigated as a function of pH, contact time and adsorbent dose. The kinetics of adsorption and reusability potential of the adsorbent were also performed. A pseudo-second-order kinetics for mercury adsorption was observed. As prepared MoS2 nanosheets showed 93% mercury removal efficiency, whereas regenerated adsorbent showed 91% and 79% removal efficiency in the respective 2nd and 3rd cycles. The adsorption capacity of the adsorbent was found to be 289 mg/g at room temperature.

关键词： Anionic surfactant 2D material MoS₂ nanosheets Mercury removal Adsorption capacity

HTML PDF 收藏

CO₂ capture using membrane contactors: a systematic literature review

M. Al-Salem, Achilleas Constantinou

《化学科学与工程前沿（英文）》 2021年第15卷第4期页码 720-754 doi: 10.1007/s11705-020-1992-z

摘要： With fossil fuel being the major source of energy, CO emission levels need to be reduced to a minimal amount namely from anthropogenic sources. Energy consumption is expected to rise by 48% in the next 30 years, and global warming is becoming an alarming issue which needs to be addressed on a thorough technical basis. Nonetheless, exploring CO capture using membrane contactor technology has shown great potential to be applied and utilised by industry to deal with post- and pre-combustion of CO . A systematic review of the literature has been conducted to analyse and assess CO removal using membrane contactors for capturing techniques in industrial processes. The review began with a total of 2650 papers, which were obtained from three major databases, and then were excluded down to a final number of 525 papers following a defined set of criteria. The results showed that the use of hollow fibre membranes have demonstrated popularity, as well as the use of amine solvents for CO removal. This current systematic review in CO removal and capture is an important milestone in the synthesis of up to date research with the potential to serve as a benchmark databank for further research in similar areas of work. This study provides the first systematic enquiry in the evidence to research further sustainable methods to capture and separate CO .

关键词： CO₂ capture preferred reporting items for systematic reviews and meta-analyses membrane contactor absorbent

HTML PDF 收藏

Inexpensive synthesis of a high-performance Fe

Shao, Syed M. Imran, Muhammad S. Haider, Hee Taik Kim

《化学科学与工程前沿（英文）》 2016年第10卷第3期页码 405-416 doi: 10.1007/s11705-016-1579-x

摘要： A sol-gel technique has been developed for the synthesis of a magnetite-silica-titania (Fe O -SiO -TiO ) tertiary nanocomposite with improved photocatalytic properties based on the use of inexpensive titania and silica precursors. The exceptional photocatalytic activity of the resulting materials was demonstrated by using them to photocatalyze the degradation of methylene blue solution. The best formulation achieved 98% methylene blue degradation. An interesting feature of the present work was the ability to magnetically separate and reuse the catalyst. The efficiency of the catalyst remained high during two reuses. The synthesized nanomaterials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy, ultra-violet-visible spectroscopy, diffuse reflectance spectroscopy, and thermogravimetric analysis. XRD analysis revealed the formation of multicrystalline systems of cubic magnetite and anatase titania crystals. SEM and TEM characterization revealed well-developed and homogeneously dispersed particles of size less than 15 nm. FTIR spectra confirmed the chemical interaction of titania and silica. It was further noticed that the optical properties of the prepared materials were dependent on the relative contents of their constituent metal oxides.

关键词： sol-gel photocatalysis magnetic recovery TiO₂ Fe₃O₄ SiO₂

HTML PDF 收藏

Bamboo-like -doped carbon nanotubes encapsulating M(Co, Fe)-Ni alloy for electrochemical production of

《化学科学与工程前沿（英文）》 2022年第16卷第4期页码 498-510 doi: 10.1007/s11705-021-2082-6

摘要： The electrochemical conversion of CO₂-H₂O into CO-H₂ using renewable energy is a promising technique for clean syngas production. Low-cost electrocatalysts to produce tunable syngas with a potential-independent CO/H₂ ratio are highly desired. Herein, a series of N-doped carbon nanotubes encapsulating binary alloy nanoparticles (M_xNi-NCNT, M= Fe, Co) were successfully fabricated through the co-pyrolysis of melamine and metal precursors. The M_xNi-NCNT samples exhibited bamboo-like nanotubular structures with a large specific surface area and high degree of graphitization. Their electrocatalytic performance for syngas production can be tuned by changing the alloy compositions and modifying the electronic structure of the carbon nanotube through the encapsulated metal nanoparticles. Consequently, syngas with a wide range of CO/H₂ ratios, from 0.5:1 to 3.4:1, can be produced on M_xNi-NCNT. More importantly, stable CO/H₂ ratios of 2:1 and 1.5:1, corresponding to the ratio to produce biofuels by syngas fermentation, could be realized on Co₁Ni-NCNT and Co₂Ni-NCNT, respectively, over a potential window of –0.8 to –1.2 V versus the reversible hydrogen electrode. Our work provides an approach to develop low-cost and potential-independent electrocatalysts to effectively produce syngas with an adjustable CO/H₂ ratio from electrochemical CO₂ reduction.

关键词： electrochemical reduction of CO₂ syngas N-doped carbon nanotubes encapsulated alloy nanoparticles CO/H₂ ratio

HTML PDF 收藏

Orderly decorated nanostructural photoelectrodes with uniform spherical TiO

M. Bakhshayesh,S. S. Azadfar

《化学科学与工程前沿（英文）》 2015年第9卷第4期页码 532-540 doi: 10.1007/s11705-015-1549-8

摘要： This study presents a novel nanostructural electrode made of 20-nm-diameter nanoparticles, which orderly decorated with 2-µm TiO particles, deposited by a new gel process. The decorated electrode (DE) is better than the non-decorated electrode (NE) in both light scattering and light harvesting, as confirmed by diffuse reflectance spectroscopy. X-ray diffraction reveals that both electrodes have a mixture of anatase and rutile phases. The dye-sensitized solar cell based on the decorated electrode shows the highest power conversion efficiency of 7.80% as a result of less recombination demonstrated by electrochemical impedance spectroscopy. From internal power conversion efficiency measurement, the external quantum efficiency of DE cell at 530 nm is 89%, which is higher than that of NE cell (77%).

关键词： dye-sensitized solar cell uniform particles TiO₂ gel process light harvesting

HTML PDF 收藏

Glucagon-like peptide-2 exhibits protective effect on hepatic ischemia-reperfusion injury in rats

null

《医学前沿（英文）》 2015年第9卷第3期页码 368-373 doi: 10.1007/s11684-015-0403-1

摘要：

Glucagon-like peptide-2 (GLP-2) has potent anti-inflammatory effects and protects against experimental ischemia/reperfusion (I/R) injury in pulmonary, intestinal, and myocardial tissue. However, its protective abilities against I/R injury in the liver are unknown. We investigated the potential role of GLP-2 pretreatment on hepatic I/R injury in rats. A total of 24 rats were randomly divided into three groups (n = 8). The first group was the control group; the second group was the vehicle-treated hepatic ischemia/reperfusion (HIR, vehicle saline-treated) group; and the third group was the GLP-2 pretreated I/R (GLP2-IR) group. Each rat in the third group was intraperitoneally administered 5 μg GLP-2 for 5 d before the procedure. A portal triad was created to induce ischemia with a vascular atraumatic clamp. After 40 min, the clamp was released to initiate hepatic reperfusion for 6 h. Blood samples and tissue specimens from the liver were obtained. Alanine aminotransferase, aspartate aminotransferase, and total bilirubin levels significantly increased in the saline-treated HIR group (P<0.001), whereas GLP-2 pretreatment significantly decreased their levels (P<0.01). Our data suggested that GLP-2 pretreatment may have a protective effect on liver I/R injury. However, dose-response studies are necessary to determine the most effective dose.

关键词： ischemia/reperfusion liver glucagon-like peptide-2 alanine aminotransferase

HTML PDF 收藏

A multi-integrated approach on toxicity effects of engineered TiO

Ana PICADO,Susana M. PAIXÃO,Liliana MOITA,Luis SILVA,Mário S.

《环境科学与工程前沿（英文）》 2015年第9卷第5期页码 793-803 doi: 10.1007/s11783-015-0775-0

摘要： The new properties of engineered nanoparticles drive the need for new knowledge on the safety, fate, behavior and biologic effects of these particles on organisms and ecosystems. Titanium dioxide nanoparticles have been used extensively for a wide range of applications, e.g, self-cleaning surface coatings, solar cells, water treatment agents, topical sunscreens. Within this scenario increased environmental exposure can be expected but data on the ecotoxicological evaluation of nanoparticles are still scarce. The main purpose of this work was the evaluation of effects of TiO nanoparticles in several organisms, covering different trophic levels, using a battery of aquatic assays. Using fish as a vertebrate model organism tissue histological and ultrastructural observations and the stress enzyme activity were also studied. TiO nanoparticles (Aeroxide® P25), two phase composition of anatase (65%) and rutile (35%) with an average particle size value of 27.6±11 nm were used. Results on the EC for the tested aquatic organisms showed toxicity for the bacteria, the algae and the crustacean, being the algae the most sensitive tested organism. The aquatic plant showed no effect on growth. The fish showed no effect on a 21 day survival test, though at a biochemical level the cytosolic Glutathione-S-Transferase total activity, in intestines, showed a general significant decrease ( <0.05) after 14 days of exposure for all tested concentrations. The presence of TiO nanoparticles aggregates were observed in the intestine lumen but their internalization by intestine cells could not be confirmed.

关键词： ecotoxicity enzymatic analysis histology transmission electron microscopy (TEM) TiO₂-nanoparticles