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 170

会议视频 153

会议信息 2

会议专题 1

年份

2024 1

2023 31

2022 61

2021 126

2020 34

2019 11

2018 8

2017 11

2016 5

2015 4

2014 4

2013 2

2012 7

2011 5

2010 2

2009 1

2008 6

2007 4

2006 3

展开︾

关键词

碳中和 26

绿色化工 20

信息技术 16

钢结构 16

桥梁隧道 11

人工智能 10

智能制造 9

高分子材料 9

核能 8

5G 4

Engineering期刊工作 3

农业科学 3

环境 3

营养健康 3

2020 2

2021全球十大工程成就 2

大数据 2

智慧城市 2

展开︾

检索范围：

排序：展示方式：

Boehmite-supported CuO as a catalyst for catalytic transfer hydrogenation of 5-hydroxymethylfurfuralto 2,5-bis(hydroxymethyl)furan

《化学科学与工程前沿（英文）》 2023年第17卷第4期页码 415-424 doi: 10.1007/s11705-022-2225-4

摘要： 2,5-bis(hydroxymethyl)furan (BHMF) is an important monomer of polyester. Its oxygen-containing rigid ring structure and symmetrical diol functional group establish it as an alternative to petroleum-based monomer with unique advantages for the prodution of the degradable bio-based polyester materials. Herein, we prepared a boehmite-supported copper-oxide catalyst for the selective hydrogenation of 5-hydroxymethylfurfural into BHMF via catalytic transfer hydrogenation (CTH). Further, ethanol successfully replaced conventional high-pressure hydrogen as the hydrogen donor, with up to 96.9% BHMF selectivity achieved under suitable conditions. Through characterization and factor investigations, it was noted that CuO is crucial for high BHMF selectivity. Furthermore, kinetic studies revealed a higher by-product activation energy compared to that of BHMF, which explained the influence of reaction temperature on product distribution. To establish the catalyst structure-activity correlation, a possible mechanism was proposed. The copper-oxide catalyst deactivated following CTH because ethanol reduced the CuO, which consequently decreased the active sites. Finally, calcination of the catalyst in air recovered its activity. These results will have a positive impact on hydrogenation processes in the biomass industry.

关键词： biomass 5-hydroxymethylfurfural 2 5-bis(hydroxymethyl)furan transfer hydrogenation catalysis

HTML PDF 收藏

Thermoresponsive block copolymer supported Pt nanocatalysts for base-free aerobic oxidation of 5-hydroxymethyl

《化学科学与工程前沿（英文）》 2021年第15卷第6期页码 1514-1523 doi: 10.1007/s11705-021-2092-4

摘要： A base-free catalytic system for the aerobic oxidation of 5-hydroxymethyl-2-furfural was exploited by using Pt nanoparticles immobilized onto a thermoresponsive poly(acrylamide-co-acrylonitrile)-b-poly(N-vinylimidazole) block copolymer, with an upper critical solution temperature of about 45 °C. The Pt nanocatalysts were well-dispersed and highly active for the base-free oxidation of 5-hydroxymethyl-2-furfural by molecular oxygen in water, affording high yields of 2,5-furandicarboxylic acid (up to>99.9%). The imidazole groups in the block copolymer were conducive to the improvement of catalytic performance. Moreover, the catalysts could be easily separated and recovered based on their thermosensitivity by cooling the reaction system below the upper critical solution temperature. Good stability and reusability were observed over these copolymer-immobilized catalysts with no obvious decrease in catalytic activity in the five consecutive cycles.

关键词： aerobic oxidation base-free 5-hydroxymethyl-2-furfural Pt nanoparticle thermoresponsive block copolymer

HTML PDF 收藏

Synthesis and characterization of 2,5-bis[4-(2-arylvinyl)phenyl]-1,3,4-oxadiazoles with two-photon fluorescence

ZHU Xiaoqin, QIAN Ying, LU Zhifeng

《化学科学与工程前沿（英文）》 2007年第1卷第4期页码 381-384 doi: 10.1007/s11705-007-0069-6

摘要： Four novel 2,5-bis[4-(2-arylvinyl)phenyl]-1,3,4-oxadiazoles that exhibit strong two-photon absorption and enhanced two-photon excited fluorescence were designed and synthesized based on push-core-pull-core-push molecules built from embedding electron-transporting 1,3,4-oxadiazole in aromatic conjugated system through Wittig-Horner reaction. Their chemical structures were determined to show trans-vinylene character according to infrared (IR) and H nuclear magnetic resonance (NMR) spectra. A very effective energy transfer from the excited units to the ?-conjugated bridging unit can enhance the two-photon absorption and two-photon fluorescence.

关键词： 2-arylvinyl trans-vinylene character effective fluorescence push-core-pull-core-push

HTML PDF 收藏

Synthesis of mono and bis-4-methylpiperidiniummethyl-urea as corrosion inhibitors for steel in acidic

Abbas TEIMOURI, Nasrin SOLTANI, Alireza Najafi CHERMAHINI

《化学科学与工程前沿（英文）》 2011年第5卷第1期页码 43-50 doi: 10.1007/s11705-010-0532-7

摘要： Mono and bis-4-methylpiperidiniummethyl urea were synthesized, characterized and used as new corrosion inhibitors of mild steel in the acidic media. Inhibitory effect of two compounds on mild steel surface in the 1 mol·L sulphuric acid has been studied by a series of techniques, such as potentiodynamic polarization, weight loss and quantum chemical calculation methods. Potentiodynamic polarization measurements showed that two inhibitors are mixed type. All measurements showed that inhibition efficiencies enhanced with increase of inhibitor concentration. This reveals that inhibitive actions of inhibitors were mainly due to adsorption on mild steel surface. Density functional (DFT) calculations have been carried out for the title compounds by performing HF and DFT levels of theory using the standard 6-31G* basis set.

关键词： corrosion inhibitors mild steel acidic medium theoretical studies DFT

HTML PDF 收藏

Synthesis and characterization of biodegradable thermoplastic elastomers derived from N′,N-bis (2-carboxyethyl

Jiaojiao Shang, Guo Yao, Ronghui Guo, Wei Zheng, Long Gu, Jianwu Lan

《化学科学与工程前沿（英文）》 2018年第12卷第3期页码 457-466 doi: 10.1007/s11705-018-1716-9

摘要：

Biodegradable poly(ether-imide-ester) elastomers were synthesized from succinic acid, 1,4-butanediol, polyethylene glycol 1000 and N′,N-bis(2-carboxyethyl)-pyromellitimide which was derived from pyromellitic dianhydride and glycine. The chemical structures, crystallinities, thermal stabilities, mechanical properties, hydrophilicities and biodegradabilities of these elastomers were investigated. The hard segments of the linear aliphatic poly(ether-ester) exhibited monoclinic chain packing. Increasing the amount of aromatic bisimide moieties in the poly(ether-ester) reduced the crystallinity of the material and improved the thermal stability and tensile strength of the elastomers. In addition, introducing a suitable amount of aromatic bisimide moieties into the poly(ether-ester) backbones endowed the elastomers with improved biodegradability but too many aromatic bisimide groups reduced the biodegradability of the elastomers.

关键词： thermoplastic elastomers biodegradability thermo-stability mechanical property aromatic bisimide moiety

HTML PDF 收藏

Study on a green synthesis of

Aixin WANG, Yuanbin SHE, Jing FAN

《化学科学与工程前沿（英文）》 2009年第3卷第2期页码 219-221 doi: 10.1007/s11705-009-0058-z

摘要： A novel method for the synthesis of -oxo-bis[tetraarylporphyrinatoiron] ([TRPPFe] O) based on the reaction between tetraarylporphyrinironchloride (TRPPFeCl) and H O in toluene was investigated in this paper. Three kinds of [TRPPFe] O were synthesized by this novel synthetic method, and their structures were characterized by elemental analysis, IR spectra and UV-Vis spectroscopy.

关键词： μ-oxo-bis[tetraarylphenylporphinatoiron] green synthesis water

HTML PDF 收藏

Polymerization of methyl methacrylate catalyzed by mono-/bis-salicylaldiminato nickel(II) complexes and

Jihong LU, Danfeng ZHANG, Qian CHEN, Buwei YU

《化学科学与工程前沿（英文）》 2011年第5卷第1期页码 19-25 doi: 10.1007/s11705-010-0546-1

摘要： Two types of salicylaldiminato-based nickel complexes, mono-ligated Ni(II) complexes ([O-C H - - C(H)=N-Ar]Ni(PPh )(Ph) ( ), [O-(3,5-Br )C H - -C(H)=N-Ar]Ni(PPh )(Ph) ( ), [O-(3- -Bu)C H - -C(H)=N-Ar]Ni(PPh )(Ph) ( )) and bis-ligated Ni(II) complexes ([O-(3,5-Br )C H - -C(H)=N-Ar] Ni ( ), [O-(3,5-Br )C H - -C(H)=N-2-C H (PhO)] Ni ( ), Ar=2,6-C H ( -Pr) ) were synthesized and characterized by Fourier transform infrared spectroscopy (FT-IR), nuclear magnetic resonance (NMR), mass spectrography (MS) and elemental analysis (EA). In the presence of methylaluminoxane (MAO) as cocatalyst, all the nickel complexes exhibited high activities for the polymerization of methyl methacrylate (MMA) and syndiotactic-rich poly(methyl methacrylate) (PMMA) was obtained. The complexes with less bulky substituents on salicylaldiminato framework possessed higher activities, while with the same salicylaldiminato, the mono-ligated nickel complexes showed higher catalytic activity than bis-ligated ones.

关键词： late transition metal catalyst methyl methacrylate polymerization salicylaldiminato nickel complexes methylaluminoxane syndiotactic structure

HTML PDF 收藏

5G成效未达预期

Mitch Leslie

《工程（英文）》 2023年第29卷第10期页码 5-7 doi: 10.1016/j.eng.2023.08.003

HTML PDF 收藏

基于 5G技术的教育信息化应用研究

卢向群,孙禹

《中国工程科学》 2019年第21卷第6期页码 120-128 doi: 10.15302/J-SSCAE-2019.06.020

摘要：

教育信息化日益普及，智慧学习空间不断出现，学生对学习内容的个性化、便捷化、多样化需求也日益凸显，而第五代移动通信（ 5G）技术以其大带宽、本文重点探索 5G技术的教育信息化应用，在梳理教育信息化主要特征的基础上，分析了我国教育网络面临的技术挑战，从教学、教研、教育管理三方面着手，论证提出相应的 5G应用场景，形成 5G教育信息化总体视图。面向 2035年， 5G的技术普及与应用拓展，将不断丰富教育场景的内涵，推动教育场景的变革，成为我国教育信息化创新的原生动力。

关键词：教育信息技术教育信息化 5G 技术应用场景

HTML PDF 收藏

5G应用下的MIMO阵列天线去耦方法综述 Review Articles

Xiao-xi ZHANG, Ai-di REN, Ying LIU

《信息与电子工程前沿（英文）》 2020年第21卷第1期页码 62-71 doi: 10.1631/FITEE.1900466

摘要：提出一种面向微纳卫星的自主汽化管理液氨推进系统。相比常规冷气或液化气推进系统，提出多路平行筛孔式汽化装置和对应汽化控制方法。所提方案有效解决了液氨高汽化潜热和不易完全汽化的问题，从而发挥液氨推进剂高贮存密度和高比冲性能优势。此外，重点分析自主汽化管理液氨推进系统的工作流程及其涉及的物理化学过程和数学模型。综合考虑推力表现和能源效率，提出最优系统推力控制策略。地面测试表明，自主汽化管理液氨推进系统总重1.8 kg（包含0.34 kg液氨推进剂），比冲达到100 s，系统功耗在10 W以下。自主汽化管理液氨推进系统具有高比冲、低功耗、可实现性强、推力输出均一稳定等特点，适合微纳卫星在轨应用。

关键词： MIMO阵列；5G手机；去耦方法

HTML PDF 收藏

lncR-GAS5 upregulates the splicing factor to impair endothelial autophagy, leading to atherogenesis

《医学前沿（英文）》 2023年第17卷第2期页码 317-329 doi: 10.1007/s11684-022-0931-4

摘要： Long noncoding RNAs (lncRNAs) play a critical role in the regulation of atherosclerosis. Here, we investigated the role of the lncRNA growth arrest-specific 5 (lncR-GAS5) in atherogenesis. We found that the enforced expression of lncR-GAS5 contributed to the development of atherosclerosis, which presented as increased plaque size and reduced collagen content. Moreover, impaired autophagy was observed, as shown by a decreased LC3II/LC3I protein ratio and an elevated P62 level in lncR-GAS5-overexpressing human aortic endothelial cells. By contrast, lncR-GAS5 knockdown promoted autophagy. Moreover, serine/arginine-rich splicing factor 10 (SRSF10) knockdown increased the LC3II/LC3I ratio and decreased the P62 level, thus enhancing the formation of autophagic vacuoles, autolysosomes, and autophagosomes. Mechanistically, lncR-GAS5 regulated the downstream splicing factor SRSF10 to impair autophagy in the endothelium, which was reversed by the knockdown of SRSF10. Further results revealed that overexpression of the lncR-GAS5-targeted gene miR-193-5p promoted autophagy and autophagic vacuole accumulation by repressing its direct target gene, SRSF10. Notably, miR-193-5p overexpression decreased plaque size and increased collagen content. Altogether, these findings demonstrate that lncR-GAS5 partially contributes to atherogenesis and plaque instability by impairing endothelial autophagy. In conclusion, lncR-GAS5 overexpression arrested endothelial autophagy through the miR-193-5p/SRSF10 signaling pathway. Thus, miR-193-5p/SRSF10 may serve as a novel treatment target for atherosclerosis.

关键词： lncR-GAS5 miR-193-5p splicing factor SRSF10 autophagy atherogenesis

HTML PDF 收藏

2020普遍通信与5G技术国际会议(UC5G 2020)

会议日期： 2020年03月26日

会议地点：上海

主办单位： APISE

一场潜在的5G干扰风暴

Chris Palmer

《工程（英文）》 2019年第5卷第5期页码 815-816 doi: 10.1016/j.eng.2019.08.007

HTML PDF 收藏

2020年5G移动通信与信息科学国际学术会议（MCIS-5G2020）

会议日期： 2020年06月26日

会议地点：广东广州

5G综述及中国的进展 None

Shan-zhi CHEN, Shao-li KANG

《信息与电子工程前沿（英文）》 2018年第19卷第3期页码 309-321 doi: 10.1631/FITEE.1800070

摘要： 5G技术、标准和产业化从20012年开始高速发展，是全球经济新的驱动力。本文全面介绍了5G，包括愿景、要求、演进、关键技术、标准化、频谱分配、技术试验、产业化进展和5G主要贡献者。同时指出，中国企业作为5G主要技术和标准的贡献者，正处于“5G引领”过程中。最后介绍了5G最新进展和作者关于5G的再思考。

关键词： 5G；IMT-2020；关键技术；标准；现场试验

HTML PDF 收藏

标题作者时间类型操作

Boehmite-supported CuO as a catalyst for catalytic transfer hydrogenation of 5-hydroxymethylfurfuralto 2,5-bis(hydroxymethyl)furan

期刊论文

Thermoresponsive block copolymer supported Pt nanocatalysts for base-free aerobic oxidation of 5-hydroxymethyl

期刊论文

Synthesis and characterization of 2,5-bis[4-(2-arylvinyl)phenyl]-1,3,4-oxadiazoles with two-photon fluorescence

ZHU Xiaoqin, QIAN Ying, LU Zhifeng

期刊论文

Synthesis of mono and bis-4-methylpiperidiniummethyl-urea as corrosion inhibitors for steel in acidic

Abbas TEIMOURI, Nasrin SOLTANI, Alireza Najafi CHERMAHINI