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Bioorthogonal chemistry based on-demand drug delivery system in cancer therapy

《化学科学与工程前沿（英文）》 2023年第17卷第4期页码 483-489 doi: 10.1007/s11705-022-2227-2

摘要： Benefiting from the advantage of taking place in biological environments without interfering with an innate biochemical process, the bioorthogonal reaction that commonly contains the “bond formation” and “bond cleavage” system has been widely used in targeted therapy for a variety of tumors. Herein, several prominent cases based on the bioorthogonal reaction that tailoring the metabolic glycoengineering tactics to modified cells for cancer immunotherapy, and the innovative tactics for reducing the metal ions’ toxic and side effects with microneedle patches will be highlighted. Based on these applications, the complexities, potential pitfalls, and opportunities of bioorthogonal chemistry in future cancer therapy will be evaluated.

关键词： bioorthogonal reaction cancer therapy metabolic glycoengineering bioorthogonal catalytic patch

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Nicotine gum or patch treatment for smoking cessation and smoking reduction: a multi-centre study in

null

《医学前沿（英文）》 2014年第8卷第1期页码 84-90 doi: 10.1007/s11684-014-0311-9

摘要：

In China, around 23% of physicians (41% male, 3% female) currently smoke. Pharmacotherapy for tobacco dependence is available, but is not widely used in China. The purpose of this study was to estimate the effectiveness and the safety on smoking cessation of nicotine gum and nicotine patch in Chinese healthcare professionals. Three hundred regular smokers motivated to quit were recruited from six hospitals in China. All subjects were accepted nicotine replacement therapy, and they could choose nicotine gum (2 mg or 4 mg, depending on baseline smoking level) or nicotine patch (15 mg/16 h) for 12 weeks, with a 12-week follow-up. Limited behavioural support was provided. At Week 24, the 2--24 weeks continuous abstinence rate (verified by expired carbon monoxide) was 17%, the point prevalence abstinence rate (no smoking since the previous visit) was 35%, and 38% of subjects had continuously reduced their daily cigarette consumption by at least 50% versus baseline. Compliance with treatment was good, particularly with patch. No serious adverse event was reported, and most adverse events were mild or moderate. The most common treatment-related adverse events were gastro-intestinal (both gum and patch) and local irritation symptoms. Nicotine patch and gum were well tolerated in Chinese smokers. Abstinence rates were comparable to those previously reported with nicotine replacement therapy, and many smokers who did not quit substantially reduced their cigarette consumption.

关键词： nicotine replacement therapy smoking cessation Chinese physicians

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基于学习自适应区域选择的自动增强图像 None

Na LI, Jian ZHAN

《信息与电子工程前沿（英文）》 2019年第20卷第2期页码 206-221 doi: 10.1631/FITEE.1700125

摘要：如今数码相机被广泛用于日常摄影。然而，部分照片缺乏细节，需要增强处理。很多现有图像增强算法基于局部区域，而且同一图像所选区域尺寸通常是固定的。用户需手工选择合适的区域尺寸获取最佳图像增强效果。提出一种基于自适应区域选择的自动增强图像算法。该算法采用明暗两个通道，解决各类图像曝光问题。对网上爬取的大量自然图像统计分析获取阈值，自动选择用于通道提取的区域尺寸。该方法可自动增强模糊或者曝光不足/背光的图像，无需任何用户交互。实验结果表明，该算法对现有基于区域的图像增强算法有显著改进。

关键词：图像增强；对比度增强；暗通道；明通道；自适应区域处理

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基于图块的局部加权表决标记融合分割算法 Article

Kai ZHU, Gang LIU, Long ZHAO, Wan ZHANG

《信息与电子工程前沿（英文）》 2017年第18卷第5期页码 680-688 doi: 10.1631/FITEE.1500457

摘要：标记融合是医学图像处理中越来越受欢迎的一种强大的图像分割策略。然而，同时满足高精度和快速分割却是对算法的一个极大的挑战。结合局部加权表决策略和贝叶斯推论，本文提出了一种新的基于图块的分割算法。通过ANTs（Advanced normalization tools）算法将训练图谱图像向目标图像进行配准，并将配准后的训练图谱标记映射到目标图像中来获得分割结果。首先在执行局部加权表决策略中将灰度先验概率和标记先验概率作为两个关键的指标，然后在图块水平上计算这两种先验概率。接着在分析标记融合的过程中，首次提出了把图像的背景区域作为单独的一个标记值来处理，再估算标记先验概率的方案。最后，利用Dice score作为评估分割精度的标准，将该算法分割的结果与其他一些方法进行了比较，如多数表决、局部加权表决、基于图块的多数表决以及广泛运用于整个大脑分割的工具FreeSurfer。实验结果证明本文提出的算法要优于其他分割方法。在实验中，本文还讨论了不同参数（包括图块大小、图块面积和训练图谱个数）对分割精度的影响。

关键词：标记融合；局部加权表决；基于图块；背景分析

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Multi-scale UDCT dictionary learning based highly undersampled MR image reconstruction using patch-based

Min YUAN,Bing-xin YANG,Yi-de MA,Jiu-wen ZHANG,Fu-xiang LU,Tong-feng ZHANG

《信息与电子工程前沿（英文）》 2015年第16卷第12期页码 1069-1087 doi: 10.1631/FITEE.1400423

摘要： Recently, dictionary learning (DL) based methods have been introduced to compressed sensing magnetic resonance imaging (CS-MRI), which outperforms pre-defined analytic sparse priors. However, single-scale trained dictionary directly from image patches is incapable of representing image features from multi-scale, multi-directional perspective, which influences the reconstruction performance. In this paper, incorporating the superior multi-scale properties of uniform discrete curvelet transform (UDCT) with the data matching adaptability of trained dictionaries, we propose a flexible sparsity framework to allow sparser representation and prominent hierarchical essential features capture for magnetic resonance (MR) images. Multi-scale decomposition is implemented by using UDCT due to its prominent properties of lower redundancy ratio, hierarchical data structure, and ease of implementation. Each sub-dictionary of different sub-bands is trained independently to form the multi-scale dictionaries. Corresponding to this brand-new sparsity model, we modify the constraint splitting augmented Lagrangian shrinkage algorithm (C-SALSA) as patch-based C-SALSA (PB C-SALSA) to solve the constraint optimization problem of regularized image reconstruction. Experimental results demonstrate that the trained sub-dictionaries at different scales, enforcing sparsity at multiple scales, can then be efficiently used for MRI reconstruction to obtain satisfactory results with further reduced undersampling rate. Multi-scale UDCT dictionaries potentially outperform both single-scale trained dictionaries and multi-scale analytic transforms. Our proposed sparsity model achieves sparser representation for reconstructed data, which results in fast convergence of reconstruction exploiting PB C-SALSA. Simulation results demonstrate that the proposed method outperforms conventional CS-MRI methods in maintaining intrinsic properties, eliminating aliasing, reducing unexpected artifacts, and removing noise. It can achieve comparable performance of reconstruction with the state-of-the-art methods even under substantially high undersampling factors.

关键词： Compressed sensing (CS) Magnetic resonance imaging (MRI) Uniform discrete curvelet transform (UDCT) Multi-scale dictionary learning (MSDL) Patch-based constraint splitting augmented Lagrangian shrinkage algorithm (PB C-SALSA)

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Spontaneous firing properties of rat medial vestibular nucleus neurons in brain slices by infrared visual patch

XIA Jiao, KONG Weijia, ZHU Yun, ZHOU Yan, ZHANG Yu, GUO Changkai

《医学前沿（英文）》 2008年第2卷第3期页码 264-268 doi: 10.1007/s11684-008-0050-x

摘要： Domestic application of infrared patch clamp techniques on brain slices is limited. The key of the technique is to prepare high-quality brain slices. The present paper describes the preparation procedure of brainstem slices and the spontaneous firing properties of rat medial vestibular nucleus (MVN) neurons. By infrared differential interference contrast technique, neurons of rat MVN were visualized directly at the depth of 50–100 ?m underneath the surface of slices. Firing activities of MVN neurons were recorded by the whole-cell patch clamp technique in artificial cerebrospinal fluid (ACSF) and low Ca - high Mg fluid. The firing mode was more irregular and depressive in low Ca - high Mg fluid than in ACSF. According to the averaged waveform of action potentials, cells were classified as the neurons with monophasic after-hyperpolarization potential (AHP), and the neurons with biphasic AHP. The resting membrane potential (RMP), input resistance (Rin) and membrane capacitance (Cm) of neurons were recorded and compared between groups. With infrared videomicroscopy, patch clamp recordings could be made under direct observation in freshly prepared brainstem slices. The discharge activities of MVN neurons were spontaneous and the firing mode was modulated by extracellular calcium concentration. The basic membrane properties of two types of neurons were not significantly different, while the differences in waveform might play a role in the segregation between tonic and kinetic cells.

关键词： resistance infrared infrared videomicroscopy depressive after-hyperpolarization potential

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A review on catalytic & non-catalytic bio-oil upgrading in supercritical fluids

Sainab Omar, Yang Yang, Jiawei Wang

《化学科学与工程前沿（英文）》 2021年第15卷第1期页码 4-17 doi: 10.1007/s11705-020-1933-x

摘要： This review article summarizes the key published research on the topic of bio-oil upgrading using catalytic and non-catalytic supercritical fluid (SCF) conditions. The precious metal catalysts Pd, Ru and Pt on various supports are frequently chosen for catalytic bio-oil upgrading in SCFs. This is reportedly due to their favourable catalytic activity during the process including hydrotreating, hydrocracking, and esterification, which leads to improvements in liquid yield, heating value, and pH of the upgraded bio-oil. Due to the costs associated with precious metal catalysts, some researchers have opted for non-precious metal catalysts such as acidic HZSM-5 which can promote esterification in supercritical ethanol. On the other hand, SCFs have been effectively used to upgrade crude bio-oil without a catalyst. Supercritical methanol, ethanol, and water are most commonly used and demonstrate catalyst like activities such as facilitating esterification reactions and reducing solid yield by alcoholysis and hydrolysis, respectively.

关键词： bio-oil upgrading supercritical review

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Probing the catalytic activity of M-N

Fan Ge, Qingan Qiao, Xin Chen, You Wu

《化学科学与工程前沿（英文）》 2021年第15卷第5期页码 1206-1216 doi: 10.1007/s11705-020-2017-7

摘要： In this work, the detailed oxygen reduction reaction (ORR) catalytic performance of M-N O (M= Fe, Co, and Ni; = 1–4) has been explored via the detailed density functional theory method. The results suggest that the formation energy of M-N O shows a good linear relationship with the number of doped O atoms. The adsorption manner of O on M-N O changed from end-on ( = 1 and 2) to side-on ( = 3 and 4), and the adsorption strength gradually increased. Based on the results for binding strength of ORR intermediates and the Gibbs free energy of ORR steps on the studied catalysts, we screened out two highly active ORR catalysts, namely Co-N O and Ni-N O , which possess very small overpotentials of 0.27 and 0.32 V, respectively. Such activities are higher than the precious Pt catalyst. Electronic structure analysis reveals one of the reasons for the higher activity of Co-N O and Ni-N O is that they have small energy gaps and moderate highest occupied molecular orbital energy levels. Furthermore, the results of the density of states reveal that the O doping can improve the electronic structure of the original catalyst to tune the adsorption of the ORR intermediates.

关键词： M-N-C catalyst oxygen doping oxygen reduction reaction catalytic activity density functional theory

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射线与三角Bézier曲面交点的混合裁剪算法 Article

Yan-hong LIU,Juan CAO,Zhong-gui CHEN,Xiao-ming ZENG

《信息与电子工程前沿（英文）》 2016年第17卷第10期页码 1018-1030 doi: 10.1631/FITEE.1500390

摘要：概要：本文提出了一种快速、稳定的几何算法来求解射线与三角Bézier曲面的交点，我们把这种新方法称为混合裁剪算法（简称HC（hybrid clipping）算法）。若射线只穿过曲面一次，通过降阶逼近算法，我们得到参数域上的一对直线和一对二次曲线，进而可将交点的参数范围限定在一个比原参数域更小的三角域上。结合细分算法，原三角域可以被反复剪裁，直到参数域的直径小于给定的阈值。当射线与曲面的交点个数大于1时，本文利用Descartes符号法则和细分算法将参数域分割成一些子区域，使得每个子区域只包含一个交点。本文从理论上证明了，经过适当的预处理，HC算法在单根的情况下具有三阶的收敛速度。此外，HC算法具有许多优良的性质，如无需初始值以及对初始问题扰动不敏感等。数值实验也表明了HC算法在解决射线与三角Bézier曲面求交问题的有效性。

关键词：光线跟踪；三角Bézier曲面；射线与曲面的交点；求根；混合裁剪

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Effects of support acidity on the reaction mechanisms of selective catalytic reduction of NO by CH

Shicheng XU, Junhua LI, Dong YANG, Jiming HAO

《环境科学与工程前沿（英文）》 2009年第3卷第2期页码 186-193 doi: 10.1007/s11783-009-0016-5

摘要： The reaction mechanisms of selective catalytic reduction (SCR) of nitric oxide (NO) by methane (CH ) over solid superacid-based catalysts were proposed and testified by DRIFTS studies on transient reaction as well as by kinetic models. Catalysts derived from different supports would lead to different reaction pathways, and the acidity of solid superacid played an important role in determining the reaction mechanisms and the catalytic activities. Higher ratios of Br?nsted acid sites to Lewis acid sites would lead to stronger oxidation of methane and then could facilitate the step of methane activation. Strong Br?nsted acid sites would not necessarily lead to better catalytic performance, however, since the active surface NO species and the corresponding reaction routes were determined by the overall acidity strength of the support. The reaction routes where NO moiety was engaged as an important intermediate involved moderate oxidation of methane, the rate of which could determine the overall activity. The reaction involving NO moiety was likely to be determined by the step of reduction of NO. Therefore, to enhance the SCR activity of solid superacid catalysts, reactions between appropriate couples of active NO species and activated hydrocarbon intermediates should be realized by modification of the support acidity.

关键词： selective catalytic reduction (SCR) nitric oxide (NO) methane support acidity Br?nsted acid sites NO_y species

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Preparation of rare-earth metal complex oxide catalysts for catalytic wet air oxidation

LI Ning, LI Guangming, YAO Zhenya, ZHAO Jianfu

《环境科学与工程前沿（英文）》 2007年第1卷第2期页码 190-195 doi: 10.1007/s11783-007-0033-1

摘要： Catalytic wet air oxidation (CWAO) is one of the most promising technologies for pollution abatement. Developing catalysts with high activity and stability is crucial for the application of the CWAO process. The Mn/Ce complex oxide catalysts for CWAO of high concentration phenolcontaining wastewater were prepared by coprecipitation. The catalyst preparation conditions were optimized by using an orthogonal layout method and single-factor experimental analysis. The Mn/Ce serial catalysts were characterized by Brunauer Emmett Teller (BET) analysis and the metal cation leaching was measured by inductively coupled plasma torch-atomic emission spectrometry (ICP-AES). The results show that the catalysts have high catalytic activities even at a low temperature (80?C) and low oxygen partial pressure (0.5 MPa) in a batch reactor. The metallic ion leaching is comparatively low (Mn<6.577 mg/L and Ce<0.6910 mg/L, respectively) in the CWAO process. The phenol, COD, and TOC removal efficiencies in the solution exceed 98.5% using the optimal catalyst (named CSP). The new catalyst would have a promising application in CWAO treatment of high concentration organic wastewater.

关键词： torch-atomic emission Brunauer Catalytic process stability

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Properties and catalytic mechanism of -glutamyltranspeptidase from NX-2

WANG Qian, YAO Zhong, XUN Zhijing, XU Xiaoying, XU Hong, WEI Ping

《化学科学与工程前沿（英文）》 2008年第2卷第4期页码 456-461 doi: 10.1007/s11705-008-0075-3

摘要： Since -glutamyltranspeptidase (GGT) especially catalyses the transfer of the -glutamyl moiety to a variety of amino acids and short peptides, GGT has important practical value for enzymatic synthesis of -glutamyl compounds. In this paper, the GGT produced from NX-2 was purified by a combination of ammonium sulfate fractionation and ion exchange chromatography, and the properties of purified GGT were investigated. At the conditions of pH 10.0, D-glutamine (D-Gln)/L-tryptophan (L-Trp) with a molar ratio of 5 : 7, a temperature 40°C and a reaction time of 4 h, a higher conversion rate of 42% was obtained. According to the time course, the catalytic mechanism of enzymatic synthesis of -D-glutamyl-L-tryptophan (-D-Gln-L-Trp) was discussed. It was demonstrated that the GGT can catalyze not only the reaction of transpeptidation, but also the irreversible hydrolysis of the products which results in the decrease of the yield of the products. The affinity parameter of GGT to D-Gln (Km) was 5.08 mmol·L and the maximum reaction rate of transpeptidation () was determined as 0.034 mmol·min·L, while the affinity parameter of GGT to -D-Gln-L-Trp (’) was 2.267 mmol·L, and the maximum reaction rate of hydrolysis (’) was 0.012 mmol·min·L.

关键词： catalytic mechanism mmol·min·L D-glutamine affinity parameter important practical

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Multi-stage ammonia production for sorption selective catalytic reduction of NO

Chen ZHANG, Guoliang AN, Liwei WANG, Shaofei WU

《能源前沿（英文）》 2022年第16卷第5期页码 840-851 doi: 10.1007/s11708-021-0797-1

摘要： Sorption selective catalytic reduction of nitrogen oxides (NO_x) (sorption-SCR) has ever been proposed for replacing commercial urea selective catalytic reduction of NO_x (urea-SCR), while only the single-stage sorption cycle is hitherto adopted for sorption-SCR. Herein, various multi-stage ammonia production cycles is built to solve the problem of relative high starting temperature with ammonia transfer (AT) unit and help detect the remaining ammonia in ammonia storage and delivery system (ASDS) with ammonia warning (AW) unit. Except for the single-stage ammonia production cycle with MnCl₂, other sorption-SCR strategies all present overwhelming advantages over urea-SCR considering the much higher NO_x conversion driven by the heat source lower than 100°C and better matching characteristics with low-temperature catalysts. Furthermore, the required mass of sorbent for each type of sorption-SCR is less than half of the mass of AdBlue for urea-SCR. Therefore, the multifunctional multi-stage sorption-SCR can realize compact and renewable ammonia storage and delivery with low thermal energy consumption and high NO_x conversion, which brings a bright potential for efficient commercial de-NO_x technology.

关键词： selective catalytic reduction (SCR) nitrogen oxides (NO_x) ammonia composite sorbent chemisorption

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Selective catalytic reduction of NO

Pavlo I. Kyriienko

《化学科学与工程前沿（英文）》 2020年第14卷第4期页码 471-491 doi: 10.1007/s11705-019-1847-7

摘要： Research results regarding selective catalytic reduction (SCR) of NO with ethanol and other C oxygenates as reductants over silver-alumina catalysts are summarized. The aspects of the process mechanism, nature of active sites, role of alumina and silver (especially in the formation of bifunctional active sites), effects of reductants and reaction conditions are discussed. It has been determined that key stages of the process include formation of reactive enolic species, their interaction with NO and formation of nitroorganic compounds which transform to NCO species and further to N . The results obtained over various silver-alumina catalysts demonstrate the perspectives of their application for reducing the level of nitrogen oxides in engine emissions, including in the presence of water vapor and sulfur oxides. Ways to improve the catalysts for the SCR of NO with C oxygenates are outlined.

关键词： SCR nitrogen oxides silver-alumina catalyst silver species ethanol oxygenates

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Effect of different acid anions on highly efficient Ce-based catalysts for selective catalytic reduction

《化学科学与工程前沿（英文）》 2023年第17卷第10期页码 1399-1411 doi: 10.1007/s11705-023-2345-5

摘要： Three kinds of Ce-based catalysts (CePO₄, CeVO₄, Ce₂(SO₄)₃) were synthesized and used for the selective catalytic reduction (SCR) of NO by NH₃. NH₃-SCR performances were conducted in the temperature range of 80 to 400 °C. The catalytic efficiencies of the three catalysts are as follow: CePO₄ > CeVO₄ > Ce₂(SO₄)₃, which is in agreement with their abilities of NH₃ adsorption capacities. The highest NO conversion rate of CePO₄ could reach about 95%, and the catalyst had more than 90% NO conversion rate between 260 and 320 °C. The effect of PO₄^3–, VO₄^3– and SO₄^2– on NH₃-SCR performances of Ce-based catalysts was systematically investigated by the X-ray photoelectron spectroscopy analysis, NH₃ temperature programmed desorption, H₂ temperature programmed reduction and field emission scanning electron microscopy tests. The key factors that can enhance the SCR are the existence of Ce⁴⁺, large NH₃ adsorption capacity, high and early H₂ consumptions, and suitable microstructures for gas adsorption. Finally, CePO₄ and CeVO₄ catalysts also exhibited relatively strong tolerance of SO₂, and the upward trend about 8% was detected due to the sulfation enhancement by SO₂ for Ce₂(SO₄)₃.

关键词： CePO₄ CeVO₄ Ce₂(SO₄)₃ selective catalytic reduction NO removal