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 1120

年份

2024 2

2023 79

2022 82

2021 88

2020 107

2019 72

2018 65

2017 67

2016 46

2015 56

2014 45

2013 37

2012 36

2011 38

2010 47

2009 46

2008 56

2007 49

2006 24

2005 17

展开︾

关键词

设计 4

COVID-19 3

三峡库区 3

医院中子照射器 3

可持续发展 3

肠道菌群 3

2型糖尿病 2

HY-2 2

SARS-CoV-2 2

SWAT模型 2

“一带一路” 2

上海港 2

中国铁路“走出去” 2

主动控制 2

优化 2

优化设计 2

区块链 2

可再生能源 2

展开︾

检索范围：

排序：展示方式：

Wu Lien-Teh’s epidemic preventive system for plague control

null

《医学前沿（英文）》 2018年第12卷第1期页码 113-115 doi: 10.1007/s11684-018-0613-4

摘要：

Pneumonic plague that originated in Russian Siberia broke out in Northeast China in October 1910–March 1911. On the basis of field visits, autopsy, bacteriological identification, and close collaboration with local authorities and international colleagues, Dr. Wu Lien-Teh implemented a series of efficient antiplague measures, which successfully controlled the development of an extraordinary epidemic plague. In his subsequent work, Dr. Wu demonstrated the respiratory transmission of pneumonic plague and tarbagans’ role in this spread. Dr. Wu’s academic and cultural contributions are valuable in the medical progress in China.

关键词： pneumonic plague prevention epidemic control Wu Lien-Teh

HTML PDF 收藏

Additive direct-write microfabrication for MEMS: A review

Kwok Siong TEH

《机械工程前沿（英文）》 2017年第12卷第4期页码 490-509 doi: 10.1007/s11465-017-0484-4

摘要：

Direct-write additive manufacturing refers to a rich and growing repertoire of well-established fabrication techniques that builds solid objects directly from computer-generated solid models without elaborate intermediate fabrication steps. At the macroscale, direct-write techniques such as stereolithography, selective laser sintering, fused deposition modeling ink-jet printing, and laminated object manufacturing have significantly reduced concept-to-product lead time, enabled complex geometries, and importantly, has led to the renaissance in fabrication known as the . The technological premises of all direct-write additive manufacturing are identical—converting computer generated three-dimensional models into layers of two-dimensional planes or slices, which are then reconstructed sequentially into three-dimensional solid objects in a layer-by-layer format. The key differences between the various additive manufacturing techniques are the means of creating the finished layers and the ancillary processes that accompany them. While still at its infancy, direct-write additive manufacturing techniques at the microscale have the potential to significantly lower the barrier-of-entry—in terms of cost, time and training—for the prototyping and fabrication of MEMS parts that have larger dimensions, high aspect ratios, and complex shapes. In recent years, significant advancements in materials chemistry, laser technology, heat and fluid modeling, and control systems have enabled additive manufacturing to achieve higher resolutions at the micrometer and nanometer length scales to be a viable technology for MEMS fabrication. Compared to traditional MEMS processes that rely heavily on expensive equipment and time-consuming steps, direct-write additive manufacturing techniques allow for rapid design-to-prototype realization by limiting or circumventing the need for cleanrooms, photolithography and extensive training. With current direct-write additive manufacturing technologies, it is possible to fabricate unsophisticated micrometer scale structures at adequate resolutions and precisions using materials that range from polymers, metals, ceramics, to composites. In both academia and industry, direct-write additive manufacturing offers extraordinary promises to revolutionize research and development in microfabrication and MEMS technologies. Importantly, direct-write additive manufacturing could appreciably augment current MEMS fabrication technologies, enable faster design-to-product cycle, empower new paradigms in MEMS designs, and critically, encourage wider participation in MEMS research at institutions or for individuals with limited or no access to cleanroom facilities. This article aims to provide a limited review of the current landscape of direct-write additive manufacturing techniques that are potentially applicable for MEMS microfabrication.

关键词： direct-write additive manufacturing microfabrication MEMS

HTML PDF 收藏

Preparation and characterization of polyimide/silica/silver composite films

JIANG Lizhong, WU Dezhen, LUO Ning, WU Zhanpeng, MOU Nanxiang

《化学科学与工程前沿（英文）》 2008年第2卷第3期页码 291-295 doi: 10.1007/s11705-008-0059-3

摘要： Polyimide/silica/silver hybrid films were prepared by the sol-gel method combined with single-stage self-metallization technique. The structure of polyimide films in the thermal curing process and the influence of silica content on the migration and aggregation of silver particles to the surface of hybrid films were investigated. The hybrid films were characterized by transmission electron microscopy, dynamic mechanical thermal analysis, Fourier transform infrared spectroscopy, ultraviolet visible spectroscopy and mechanical measurements. The results indicated that there was no degradation of the polyimide matrix after the formation of silica and silver particles. Silica acted as the nucleus for the silver particles. With increasing silica content, more and more silver particles were kept in the hybrid films instead of being migrated onto the surface of the hybrid films and the reflections of hybrid films decreased gradually.

关键词： single-stage self-metallization spectroscopy transmission Polyimide/silica/silver ultraviolet visible

HTML PDF 收藏

Reflections on the system of evaluation of gene-edited livestock

Ziyao FAN, Tianwen WU, Kui WU, Yulian MU, Kui LI

《农业科学与工程前沿（英文）》 2020年第7卷第2期页码 211-217 doi: 10.15302/J-FASE-2019303

摘要：

The rapid development of biotechnology has provided a greater understanding of the biological functions of major candidate genes that have important functions regarding economic traits, and new materials for livestock breeding have been obtained through gene editing (GE) and embryo manipulation with the purpose of improving quality and output and reducing the costs and risk of disease. Public concerns, particularly over safety risks and production performance, must be addressed. Evaluation is the most important component of the regulation of gene-edited livestock and is a crucial guarantee of public safety before the marketing of gene-edited animal products. Here, the system of evaluation of gene-edited livestock is discussed in terms of public safety and production performance. The search for safe and ethical applications in the GE of livestock, a case-by-case evaluation strategy, and classification and simplification are used in order to promote a more efficient, objective, comprehensive and operable evaluation system.

关键词： evaluation gene editing livestock performance safety

HTML PDF 收藏

p53 functional activation is independent of its genotype in five esophageal squamous cell carcinoma cell lines

Junfang JI, Kun WU, Min WU, Qimin ZHAN,

《医学前沿（英文）》 2010年第4卷第4期页码 412-418 doi: 10.1007/s11684-010-0260-x

摘要： mutations have been found in many esophageal squamous cell carcinoma (ESCC) clinical specimens and cell lines. We reasoned that functional inactivation of wild-type or the functional activation of mutant-type might exist in these specimens and cell lines. In this study, we identified the correlation between p53 functional activation and its genotype in five different ESCC cell lines. To examine the potential p53 activation in a certain ESCC cell line, DNA damage methods including X-ray exposure and cisplatin treatment were employed to treat cells. Further, the expression of p53 protein and four transcripts of well-known p53 target genes were investigated using Western blot and reverse transcription-polymerase chain reaction (RT-PCR) after cell exposure to DNA damage. The results showed that in KYSE 30 cell line with mutant and KYSE 150 with wild-type , p53 could be activated by DNA damages. However, p53 could not be activated following the DNA damages in YES 2 with wild-type , KYSE 70 with mutant , and EC9706 with unknown genotype. All our data indicated that p53 function in certain cells is not closely correlated with its genotype. To judge p53 function in a particular cell line, it is important to examine the p53 functional activation, but not to simply rely on the genotype.

关键词： p53 esophageal squamous cell carcinoma DNA damage

HTML PDF 收藏

Functional characterization of caffeic acid

Fengyan WU, Zhenying WU, Aiguo YANG, Shanshan JIANG, Zeng-Yu WANG, Chunxiang FU

《农业科学与工程前沿（英文）》 2018年第5卷第1期页码 98-107 doi: 10.15302/J-FASE-2017198

摘要： Caffeic acid -methyltransferase (COMT) is a crucial enzyme that mainly methylates phenylpropanoid -hydroxyl of C in the biosynthesis of syringyl lignin in angiosperms. A putative , named as , was isolated from switchgrass ( ), a C warm-season dual-purpose forage and bioenergy crop. Our results showed that recombinant PvCOMT1 enzyme protein catalyzed the methylation of 5-OH coniferyl alcohol, 5-OH coniferaldehyde (CAld5H) and 5-OH ferulic acid. Further studies indicate that CAld5H can dominate COMT-mediated reactions by inhibiting the methylation of the other substrates. Transgenic switchgrass plants generated by an RNAi approach were further employed to study the function of in internode lignification. A dramatic decrease in syringyl lignin units coupled with an obvious incorporation in 5-OH guaiacyl lignin units were observed in the COMT-RNAi transgenic plants. However, the constitutive suppression of COMT in switchgrass plants altered neither the pattern of lignin deposition along the stem nor the anatomical structure of internodes. Consistent with the biochemical characterization of PvCOMT1, a significant decrease in sinapaldehyde was found in the COMT-RNAi transgenic switchgrass plants, suggesting that CAld5H could be the optimal intermediate in the biosynthesis syringyl lignin.

关键词： biofuel crop caffeic acid O-methyltransferase forage lignin Panicum virgatum switchgrass transgenic plant

HTML PDF 收藏

可编程软件定义网络的新架构与安全技术：综述 None

Shen WANG, Jun WU, Wu YANG, Long-hua GUO

《信息与电子工程前沿（英文）》 2018年第19卷第12期页码 1500-1521 doi: 10.1631/FITEE.1800575

摘要：当前，网络空间已经成为社会基础设施的一个重要组成部分。随着网络规模快速发展，应用程序和服务日益丰富，底层网络设备（如交换机和路由器）承载功能被不断扩展。为提升网络动态架构、安全性和服务质量，网络控制平面与数据平面的解耦是网络技术发展趋势。目前，软件定义网络（SDN）是新兴网络领域最热门、最具前景的技术之一。在SDN中，通过在专有设备部署高级别策略指导网络设备数据转发，减少网络设备复杂功能。SDN有利于实现网络新技术、新协议，提升部署功能灵活性和可操作性。然而，该新型网络技术面临架构和安全方面的新挑战。本文为可编程SDN最新进展相关研究提供一个全面综述，分析已被研究和有待解决的问题，并分析在框架架构和安全领域的发展趋势。

关键词：软件定义网络（SDN）；安全；可编程

HTML PDF 收藏

A Robust Tolerance Design Method Based on Fuzzy Quality Loss

CAO Yan-long, MAO Jian, YANG Jiang-xin, WU Zhao-tong, WU Li-qun

《机械工程前沿（英文）》 2006年第1卷第1期页码 101-105 doi: 10.1007/s11465-005-0010-y

摘要：

The traditional tolerance design model ignores the impact of noise factor, so that the design may be infeasible due to variations in design constraints. Based on the analysis of fuzzy factors in tolerance design and the limitations of the traditional Taguchi squared quality loss function, a fuzzy quality loss function model utilizing fuzzy theory was introduced. Concepts on fuzzy quality loss and fuzzy quality loss cost were proposed in the model. The characteristics of the new model and the advantages over the traditional Taguchi quality loss function were analyzed. A robust tolerance design model using a fuzzy quality loss function was proposed. An example was given to illustrate the proposed model. Results and comparisons show that the method is suitable and reliable, and makes the conclusions more objective and reasonable.

关键词： impact function robust tolerance suitable quality

HTML PDF 收藏

Fused structures for safer and more economical constructions

Yu-Fei WU, Ying-Wu ZHOU, Biao HU, Xiaoxu HUANG, Scott SMITH

《结构与土木工程前沿（英文）》 2020年第14卷第1期页码 1-9 doi: 10.1007/s11709-019-0541-7

摘要： Safety margin and construction costs are two conflicting goals for a structure. By providing a fuse in a structure that is triggered at a certain level of over-loading, further increase of loading is prohibited and failure of the structure is changed to a safer mode. As overloading is controlled and a safer failure mode is enforced, a fused structure requires a smaller safety factor thus leading to more economical construction without compromising safety. The use of a fuse will also facilitate safer use of advanced construction materials such as fiber-reinforced polymer (FRP) composites. In this case, a fuse can transfer the sudden and dangerous failure mode associated with brittle FRP debonding or rupture to a safe and ductile failure mode at the fuse location. This paper introduces a new type of fused structure as well as an associated design philosophy and approach, in addition to examples of engineering applications.

关键词： fused structures structural fuse fiber-reinforced polymer concrete

HTML PDF 收藏

Thermal decomposition of poly(ethylene terephthalate)/mesoporous molecular sieve composites

RUN Mingtao, ZHANG Dayu, WU Sizhu, WU Gang

《化学科学与工程前沿（英文）》 2007年第1卷第1期页码 50-54 doi: 10.1007/s11705-007-0010-z

摘要： The nonisothermal and isothermal degradation processes of poly (ethylene terephthalate)/mesoporous molecular sieve (PET/MMS) composites synthesized by in-situ polymerization were studied by using thermogravimetric analysis in nitrogen. The nonisothermal degradation of the composite is found to be the first-order reaction. An iso-conversional procedure developed by Ozawa is used to calculate the apparent activation energy (), which is an average value of about 260 kJ/mol with the weight conversion from 0% to 30%, and is higher than that of neat PET. Isothermal degradation results are confirmed with the nonisothermal process, in which PET/MMS showed higher thermal stability than neat PET. The polymer in mesoporous channels has more stability due to the protection of the inorganic pore-wall. These results indicate that mesoporous MMS in PET/MMS composites improve the stability of the polymer.

关键词： polymerization isothermal degradation conversion nonisothermal degradation activation

HTML PDF 收藏

Deactivation and regeneration of TS-1/SiO

Hainan SHI, Yaquan WANG, Guoqiang WU, Wenping FENG, Yi Lin, Teng ZHANG, Xing JIN, Shuhai WANG, XiaoxueWU, Pengxu YAO

《化学科学与工程前沿（英文）》 2013年第7卷第2期页码 202-209 doi: 10.1007/s11705-013-1328-3

摘要： TS-1/SiO catalyst for the epoxidation of propylene with hydrogen peroxide in a fixed-bed reactor has been investigated. The catalyst activity decreases gradually with the online reaction time, but the selectivity of propylene epoxide is kept at about 93%. The fresh, deactivated and regenerated catalysts were characterized with X-ray diffraction, Fourier transform infrared spectroscopy, ultra-violet-visible diffuse reflectance, Brunner-Emmett-Teller method and thermogravimetric analysis, and the deactivated catalyst was regenerated with H O /methanol solution. Compared with the fresh catalyst, both the framework structure and the content of titanium in the framework of the deactivated and regenerated TS-1/SiO catalysts were not changed. The major reason of the catalyst deactivation was the blockage of the channels of the catalyst by bulky organic by-products, which covered the active centers of titanium in TS-1. The deposited materials on the deactivated TS-1/SiO catalyst could be removed by treatment with hydrogen peroxide/methanol solution or pure methanol; the higher the treatment temperature and the higher the concentration of H O in methanol, the higher the extent of the regeneration. The regeneration treatment did not influence the product selectivity in the propylene epoxidation.

关键词： TS-1/SiO₂ epoxidation of propylene fixed-bed reactor deactivation regeneration

HTML PDF 收藏

Fusaricidins in

Weicheng LIU, Xiaoli WU, Xuelian BAI, Hong ZHANG, Dan DONG, Taotao ZHANG, Huiling WU

《农业科学与工程前沿（英文）》 2018年第5卷第2期页码 262-270 doi: 10.15302/J-FASE-2017166

摘要： Four kinds of antifungal compounds from an extract of A21 with molecular masses of 883.56, 897.59, 947.55, and 961.58 Da were characterized as the members of fusaricidin-type of antibiotics according to LC-MS analysis. Fusaricidins isolated from culture filtrate displayed high antagonistic activity against several plant fungal pathogens, especially , the causal agent of gray mold. The fusaricidins biosynthetic gene cluster (BGC) from A21 was cloned by PCR and comparative cluster analysis revealed that gene , the 3′ boundary of the fusaricidin BGC in strain PKB1, was not present in fusaricidin BGC of A21, indicating that is not necessary for fusaricidin synthesis. Fusaricidin extract from A21 significantly reduced gray mold disease incidence and severity on tomato. The mRNA levels for three patho-genesis-related proteins (PRs) revealed that treatment of tomato leaves with fusaricidin extract induced the expression of PR genes to different levels, suggesting that one reason for the reduction of gray mold infection by fusaricidin is induction of PR proteins, which lead to increased resistance to pathogens. This is the first report of the application of fusaricidins to control tomato gray mold and the comparative cluster analysis provides important molecular basis for research on fusaricidin biosynthesis.

关键词： antifungal activity biosynthetic gene cluster Botrytis cinerea fusaricidin Paenibacillus polymyxa

HTML PDF 收藏

Soundscape of classical Chinese garden

YUAN Xiaomei, WU Shuoxian

《结构与土木工程前沿（英文）》 2008年第2卷第2期页码 172-178 doi: 10.1007/s11709-008-0026-6

摘要： With deep humanized connotation, the classical Chinese garden uses human intuitive sensation and personal poetic observation to express natural sound phenomena. It differs from the rational modern soundscape in western countries.

关键词： observation classical phenomena intuitive soundscape

HTML PDF 收藏

Effects of alfalfa coverage on runoff, erosion and hydraulic characteristics of overland flow on loess slope plots

Shufang WU, Pute WU, Hao FENG, G. P. Merkley

《环境科学与工程前沿（英文）》 2011年第5卷第1期页码 76-83 doi: 10.1007/s11783-011-0282-x

摘要： An evaluation of the interactions between vegetation, overland and soil erosion can provide valuable insight for the conservation of soil and water. An experiment was conducted to study water infiltration, runoff generation process, rate of sediment erosion, and hydrodynamic characteristics of overland flow from a sloping hillside with different draw-off discharges from alfalfa and control plots with 20° slope. The effect of alfalfa on runoff and sediment transport reduction was quantitatively analyzed. Alfalfa was discussed for its ability to reduce the overland flow scouring force or change the runoff movement. Compared to the bare-soil plots, alfalfa plots generated a 1.77 times increase in infiltration rate. Furthermore, the down-slope water infiltration rate for the bare soil plots was higher than in the up-slope, while the opposite was found in the alfalfa plots. In addition, alfalfa had a significant effect on runoff and sediment yield. In comparison to the control, the runoff coefficient and sediment transportation rate decreased by 28.3% and 78.4% in the grass slope, respectively. The runoff generated from the alfalfa and bare-soil plots had similar trends with an initial increase and subsequent leveling to a steady-state rate. The transport of sediment reduced with time as a consequence of the depletion of loose surface materials. The maximum sediment concentration was recorded within the first few minutes of each event. The alfalfa plots had subcritical flow while the bare-soil plots had supercritical flow, which indicate that the capability of the alfalfa slope for resisting soil erosion and sediment movement was greater than for bare soil plots. Moreover, the flow resistance coefficient and roughness coefficient for the alfalfa plots were both higher than for the bare-soil plots, which indicate that overland flow in alfalfa plots had retarded and was blocked, and the flow energy along the runoff path had gradually dissipated. Finally, the ability to erode and transport sediment had decreased.

关键词： alfalfa soil erosion runoff and sedimentation soil water infiltration overland flow hydrodynamic characteristics

HTML PDF 收藏

Design and application of a novel coal-fired drum boiler using saline water in heavy oil recovery

Junping GU, Yuxin WU, Liping WU, Man ZHANG, Hairui YANG, Junfu LYU

《能源前沿（英文）》 2020年第14卷第4期页码 715-725 doi: 10.1007/s11708-020-0690-3

摘要： In this paper, the design and operation of a novel coal-fired circulating fluidized bed (CFB) drum boiler that can generate superheated steam using saline water were introduced. The natural circulation water dynamics with a drum was adopted instead of the traditional once-through steam generator (OTSG) design, so that superheated steam can be generated for the better performance of the steam assisted gravity drainage (SAGD) technology in heavy oil recovery. The optimized staged evaporation method was proposed to further decrease the salinity of water in the clean water section of the boiler. The evaporating pipes of the salted water section were rearranged in the back pass of the boiler, where the heat load is low, to further improve the heat transfer safety. A CFB combustion technology was used for coal firing to achieve a uniform heat transfer condition with low heat flux. Pollutant control technologies were adopted to reduce pollutant emissions. Based on the field test, the recommended water standard for the coal-fired CFB drum boilers was determined. With the present technology, the treated recovery wastewater can be reused in steam-injection boilers to generate superheated steam. The engineering applications show that the boiler efficiency is higher than 90%, the blowdown rate is limited within 5.5%, and the superheat of steam can reach up to 30 K. Besides, the heavy oil recovery efficiency is significantly improved. Moreover, the pollutant emissions of SO , NO and dust are controlled within the ranges of 20–90 mg/(N·m ), 30–90 mg/(N·m ) and 2–10 mg/(N·m ) respectively.

关键词： drum steam injection boiler natural circulation recovery wastewater staged evaporation circulating fluidized bed (CFB)