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关键词

生物柴油 2

cyp17a1 1

K波段；高效率；宽带；氮化镓（GaN）；功率放大器 1

三酰甘油 1

丝孢堆黑粉菌 1

两性异形 1

产业融合 1

人工增雨 1

人工影响天气 1

人工消雾 1

人工防雹 1

价值提升 1

传热过程 1

低光增强；过滤—群聚注意力；密集连接金字塔；递归网络 1

信号叠加 1

信号增强 1

全雌群体 1

共沸 1

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Kinetics of enhanced adsorption by polarization for organic pollutants on activated carbon fiber

HAN Yanhe, QUAN Xie, ZHAO Huimin, CHEN Shuo, ZHAO Yazhi

《环境科学与工程前沿（英文）》 2007年第1卷第1期页码 83-88 doi: 10.1007/s11783-007-0016-2

摘要： The adsorption kinetics for model pollutants on activated carbon fiber (ACF) by polarization was investigated in this work. Kinetics data obtained for the adsorption of these model pollutants at open-circuit, 400 mV, and -400 mV polarization were applied to the Lagergren equation, and adsorption rate constants () were determined. With the anodic polarization of 400 mV, the capacity of sodium phenoxide was increased from 0.0083 mmol/g at open-circuit to 0.18 mmol/g, and a 17-fold enhancement was achieved; however, the capacity of -nitrophenol was decreased from 2.93 mmol/g at open-circuit to 2.65 mmol/g. With the cathodal polarization of -400 mV, the capacity of aniline was improved from 3.60 mmol/g at open-circuit to 3.88 mmol/g; however, the capacity of sodium dodecylbenzene sulfonate was reduced from 2.20 mmol/g at open-circuit to 1.59 mmol/g. The enhancement for electrosorption changed with dif ferent groups substituting. Anodic polarization enhances the adsorption of benzene with the electron-donating group. But whether anodic or not, cathodal polarization had less effect on the adsorption of electron-accepting aromatic compounds, and decreased the adsorption capacity of benzene-bearing donor-conjugate bridge-acceptor, while increasing its adsorption rate. Electrostatic interaction played a very important role in the electrosorption of ion-pollutants.

关键词： ACF activated 17-fold enhancement donor-conjugate bridge-acceptor Electrostatic interaction

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Th17 Cells in autoimmune diseases

null

《医学前沿（英文）》 2015年第9卷第1期页码 10-19 doi: 10.1007/s11684-015-0388-9

摘要：

Th17 cells are a new subset of CD4⁺ T cells involved in the clearance of extracellular pathogens and fungi. Accumulating evidence suggests that Th17 cells and their signature cytokines have a pivotal role in the pathogenesis of multiple autoimmune-mediated inflammatory diseases. Here, we summarize recent research progress on Th17 function in the development and pathogenesis of autoimmune diseases. We also propose to identify new small molecule compounds to manipulate Th17 function for potential therapeutic application to treat human autoimmune diseases, including rheumatoid arthritis, systemic lupus erythematosus, Sj?gren’s syndrome, inflammatory bowel disease, and multiple sclerosis.

关键词： IL-17 Th17 cells RORγt autoimmune diseases posttranslational modification inhibitors

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Relationship between Th17 cells and allograft rejection

Zhikun ZHENG MM, Jinsong LI MD, Ke JIANG MD,

《医学前沿（英文）》 2009年第3卷第4期页码 491-494 doi: 10.1007/s11684-009-0066-x

摘要： Thl7 cells, a special kind of auxiliary type T cells, can secrete IL-17A, IL-17F, IL-21, IL-22, etc., as a newly discovered T-cell subset in recent years. As a different subset from the Thl and Th2 cells, Th17 cells play an important role in the development of a variety of autoimmune diseases. A current study shows that the IL-6 inflammatory response of the organization in combination with the occurrence of TGF-β can induce the differentiation of Thl7 cells. IL-23 can promote the production of IL17, as well as participate in amplification and maintenance of the survival of IL-l7 generating cells. In this process, STAT3 and ROR-γt are key transcription factors for the growing of Thl7 cells. As our knowledge on Th17 family members is rapidly growing and changing, it will be important to specify their involvement in the induction and regulation of allograft rejection in animal models as well as in clinical settings. Herein, we review the key features of Th17 cells and discuss their potential relevance to transplantation immunity.

关键词： TH17 cells regulation allograft rejection

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sources of dissolved organic matter from wastewater treatment plants and their mediation effect on 17α-ethinylestradiol

《环境科学与工程前沿（英文）》 2023年第17卷第6期 doi: 10.1007/s11783-023-1669-1

摘要：

● EE2 photodegradation behavior in the presence of four WWTPs’ DOM was explored.

关键词： Photosensitivity sources 17α-ethinylestradiol Photodegradation Dissolved organic matter Wastewater treatment plants

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Traces and echoes of De Architectura by Marcus Vitruvius Pollio in the work of Xu Guangqi in 17th

Michela CIGOLA,Yibing FANG

《机械工程前沿（英文）》 2016年第11卷第1期页码 3-11 doi: 10.1007/s11465-015-0359-5

摘要：

This study aims to investigate the role played by Xu Guangqi (1562–1633), minister of the Ming Dynasty, in the development of European scientific and technical knowledge in China between the 16th and 17th centuries by analyzing a book of Western technology that he wrote, namely, Taixi Shuifa (On Western Hydraulics). Several Western books related to machine knowledge are searched to trace the source of the illustrations in Taixi Shuifa. We found that Archimedes’ screw and Ctesibius’ machine, which are included in Vitruvius’ De Architectura volumes, also appear in the work of Xu Guangqi.

关键词： Vitruvius’ De Architectura Xu Guangqi’s Taixi Shuifa Jesuit missionaries Italian Renaissance drawing representation

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Removal of 17β-estradiol in laccase catalyzed treatment processes

XIA Qing,KONG Deyang,LIU Guoqiang,HUANG Qingguo,ALALEWI Aamr,LU Junhe

《环境科学与工程前沿（英文）》 2014年第8卷第3期页码 372-378 doi: 10.1007/s11783-013-0567-3

摘要： The removal of 17β-estradiol (E2) in laccase catalyzed oxidative coupling processes was systematically studied in this work. We focused on the influence of pH and natural organic matter (NOM) on the performance of the enzymatic treatment processes. It was found that the optimal pH for E2 removal was between 4 and 6. The removal of E2 was slightly inhibited in the presence of NOM. Enzymatic transformation of E2 was second-order in kinetics with first-order to both the concentrations of the enzyme and contaminant. Mass spectrum (MS) analysis suggested that coupling products were formed through radical-radical coupling mechanism. The results of this study demonstrated that laccase catalyzed oxidative coupling process could potentially serve as a treatment strategy to control steroid estrogens.

关键词： 17β-estradiol laccase oxidative coupling processes kinetics mechanisms

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Turbidity-adaptive underwater image enhancement method using image fusion

《机械工程前沿（英文）》 2022年第17卷第3期 doi: 10.1007/s11465-021-0669-8

摘要： Clear, correct imaging is a prerequisite for underwater operations. In real freshwater environment including rivers and lakes, the water bodies are usually turbid and dynamic, which brings extra troubles to quality of imaging due to color deviation and suspended particulate. Most of the existing underwater imaging methods focus on relatively clear underwater environment, it is uncertain that if those methods can work well in turbid and dynamic underwater environments. In this paper, we propose a turbidity-adaptive underwater image enhancement method. To deal with attenuation and scattering of varying degree, the turbidity is detected by the histogram of images. Based on the detection result, different image enhancement strategies are designed to deal with the problem of color deviation and blurring. The proposed method is verified by an underwater image dataset captured in real underwater environment. The result is evaluated by image metrics including structure similarity index measure, underwater color image quality evaluation metric, and speeded-up robust features. Test results exhibit that the method can correct the color deviation and improve the quality of underwater images.

关键词： turbidity underwater image enhancement image fusion underwater robots visibility

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利用cyp17a1缺失的伪雄鲤成功构建全雌鲤群体 Article

翟刚, 舒婷婷, 陈贶新, 娄气永, 贾景怡, 黄建飞, 石闯 , 金霞, 贺江燕, 姜冬火, 钱雪桥, 胡炜, 殷战

《工程（英文）》 2022年第8卷第1期页码 181-189 doi: 10.1016/j.eng.2021.03.026

摘要：本研究针对雌鲤生长快于雄鲤的两性生长异形的特性，以cyp17a1 为靶点进行了CRISPR/Cas9介导的基因编辑操作，利用cyp17a1 敲除后形成的伪雄鲤，成功构建了全雌鲤群体首先，我们发现无论遗传性别型为XX还是XY，其cyp17a1 缺失鲤个体性腺均发育为精巢，并能正常产精。其次，利用确定的雄性特异DNA分子标记，筛选到cyp17a1 ^-/- XX伪雄个体，其具有正常的精巢发育和精子发生。将全雌群体和对照组雌雄混合群体各500 尾进行同塘生长对比养殖，至8 月龄或12 月龄时随机抽样检测，发现cyp17a1杂合突变雌鲤体重比同塘性别混养对照组分别高6.60%或32.66%

关键词：鲤两性异形生长 cyp17a1 性类固醇激素全雌群体

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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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Performance enhancement of partially shaded solar PV array using novel shade dispersion technique

Namani RAKESH,T. Venkata MADHAVARAM

《能源前沿（英文）》 2016年第10卷第2期页码 227-239 doi: 10.1007/s11708-016-0405-y

摘要： Solar photo voltaic array (SPVA) generates a smaller amount of power than the standard rating of the panel due to the partial shading effect. Since the modules of the arrays receive different solar irradiations, the P-V characteristics of photovoltaic (PV) arrays contain multiple peaks or local peaks. This paper presents an innovative method (magic square) in order to increase the generated power by configuring the modules of a shaded photovoltaic array. In this approach, the physical location of the modules in the total cross tied (TCT) connected in the solar PV array is rearranged based on the magic square arrangement pattern. This connection is done without altering any electrical configurations of the modules in the PV array. This method can distribute the shading effect over the entire PV array, without concentrating on any row of modules and can achieve global peaks. For different types of shading patterns, the output power of the solar PV array with the proposed magic square configuration is compared with the traditional configurations and the performance is calculated. This paper presents a new reconfiguration technique for solar PV arrays, which increases the PV power under different shading conditions. The proposed technique facilitates the distribution of the effect of shading over the entire array, thereby, reducing the mismatch losses caused by partial shading. The theoretical calculations are tested through simulations in Matlab/Simulink to validate the results. A comparison of power loss for different types of topologies under different types of shading patterns for a 4 × 4 array is also explained.

关键词： photovoltaic cells mismatch loss shading patterns partial shading magic square power enhancement global peaks and total cross tied (TCT)

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Revolutionizing heat transport enhancement with liquid metals: Proposal of a new industry of water-free

Haiyan LI, Jing LIU

《能源前沿（英文）》 2011年第5卷第1期页码 20-42 doi: 10.1007/s11708-011-0139-9

摘要： Water is perhaps the most widely adopted working fluid in conventional industrial heat transport engineering. However, it may no longer be the best option today due to the increasing scarcity of water resources. Furthermore, the wide variations in water supply throughout the year and across different geographic regions also makes it harder to easily access. To address this issue, finding new alternatives to replace water-based technologies is imperative. In this paper, the concept of a water-free heat exchanger is proposed and comprehensively analyzed for the first time. The liquid metal with a low melting point is identified as an ideal fluid that can flexibly be used within a wide range of working temperatures. Some liquid metals and their alloys, which have previously received little attention in thermal management areas, are evaluated. With superior thermal conductivity, electromagnetic field drivability, and extremely low power consumption, liquid metal coolants promise many opportunities for revolutionizing modern heat transport processes: serving as heat transport fluid in industries, administrating thermal management in power and energy systems, and innovating enhanced cooling in electronic or optical devices. Furthermore, comparative analyses are conducted to understand the technical barriers encountered by advanced water-based heat transfer strategies and clarify this new frontier in heat-transport study. In addition, the unique merits of liquid metals that could lead to innovative heat exchanger technologies are evaluated comprehensively. A few promising industrial situations, such as heat recovery, chip cooling, thermoelectricity generation, and military applications, where liquid metals could play irreplaceable roles, were outlined. The technical challenges and scientific issues thus raised are summarized. With their evident ability to meet various critical requirements in modern advanced energy and power industries, liquid metal-enabled technologies are expected to usher a new and global era of water-free heat exchangers.

关键词： heat exchanger liquid metal water resource heat transport enhancement coolant thermal management process engineering energy crisis chip cooling

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Numerical investigation and analysis of heat transfer enhancement in channel by longitudinal vortex based

TAO Wenquan, WU Junmei

《能源前沿（英文）》 2008年第2卷第1期页码 71-78 doi: 10.1007/s11708-008-0001-x

摘要： 3-D numerical simulations were presented for laminar flow and heat transfer characteristics in a rectangular channel with vortex generators. The effects of Reynolds number (from 800 to 3 000), the attack angle of vortex generator (from 15° to 90°) and the shape of vortex generator were examined. The numerical results were analyzed based on the field synergy principle. It is found that the inherent mechanism of the heat transfer enhancement by longitudinal vortex can be explained by the field synergy principle, that is, the second flow generated by vortex generators results in the reduction of the intersection angle between the velocity and fluid temperature gradient. The longitudinal vortex improves the field synergy of the large downstream region of longitudinal vortex generator (LVG) and the region near (LVG); however, transverse vortex only improves the synergy of the region near vortex generator. Thus, longitudinal vortex can enhance the integral heat transfer of the flow field, while transverse vortex can only enhance the local heat transfer. The synergy angle decreases with the increase of Reynolds number for the channel with LVG to differ from the result obtained from the plain channel, and the triangle winglet performs better than the rectanglar one under the same surface area condition.

关键词： inherent mechanism integral surface rectanglar longitudinal

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Effect of bond enhancement using carbon nanotubes on flexural behavior of RC beams strengthened with

《结构与土木工程前沿（英文）》 2022年第16卷第1期页码 131-143 doi: 10.1007/s11709-021-0787-8

摘要： This paper studied the effect of incorporation of carbon nanotubes (CNTs) in carbon fiber reinforced polymer (CFRP) on strengthening of reinforced concrete (RC) beams. The RC beams were prepared, strengthened in flexure by externally bonded CFRP or CNTs-modified CFRP sheets, and tested under four-point loading. The experimental results showed the ability of the CNTs to delay the initiation of the cracks and to enhance the flexural capacity of the beams strengthened with CFRP. A nonlinear finite element (FE) model was built, validated, and used to study the effect of various parameters on the strengthening efficiency of CNTs-modified CFRP. The studied parameters included concrete strength, flexural reinforcement ratio, and CFRP sheet configuration. The numerical results showed that utilization of CNTs in CFRP production improved the flexural capacity of the strengthened beams for U-shape and underside-strip configurations. The enhancement was more pronounced in the case of U-shape than in the case of use of sheet strip covers on the underside of the beam. In case of using underside-strip, the longer or the wider the sheet, the higher was the flexural capacity of the beams. The flexural enhancement of RC beams by strengthening with CNTs-modified CFRP decreased with increasing the rebar diameter and was not affected by concrete strength.

关键词： RC beams flexural strengthening CFRP CNTs finite element

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17–26.5 GHz 42.5 dBm宽带高效率GaN功率放大器设计 Correspondences

黎明1,2,李智群1,3,郑权2,蔺兰峰2,陶洪琪2

《信息与电子工程前沿（英文）》 2022年第23卷第2期页码 346-350 doi: 10.1631/FITEE.2000513

摘要：该功率放大器采用0.15 μm栅长GaN-HEMT工艺，其工作频段可以覆盖整个K频段，即17–26.5 GHz。该功率放大器采用三级放大拓扑结构，在连续波条件下，测试结果表明，在17–26.5 GHz频带范围内饱和输出功率超过42.5 dBm，平均PAE为30%，在19.8 GHz时PAE达到最大，为32.1%，

关键词： K波段；高效率；宽带；氮化镓（GaN）；功率放大器

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Numerical analysis on heat transfer enhancement by longitudinal vortex based on field synergy principle

WU Junmei, TAO Wenquan

《能源前沿（英文）》 2007年第1卷第3期页码 365-369 doi: 10.1007/s11708-007-0055-1

摘要： Three-dimensional numerical simulation results are presented for a fin-and-tube heat transfer surface with vortex generators. The effects of the Reynolds number (from 800 to 2 000) and the attack angle (30º and 45º) of a delta winglet vortex generator are examined. The numerical results are analyzed on the basis of the field synergy principle to explain the inherent mechanism of heat transfer enhancement by longitudinal vortex. The secondary flow generated by the vortex generators causes the reduction of the intersection angle between the velocity and fluid temperature gradients. In addition, the computational evaluations indicate that the heat transfer enhancement of delta winglet pairs for an aligned tube bank fin-and-tube surface is more significant than that for a staggered tube bank fin-and-tube surface. The heat transfer enhancement of the delta winglet pairs with an attack angle of 45º is larger than that with an angle of 30º. The delta winglet pair with an attack angle of 45º leads to an increase in pressure drop, while the delta winglet pair with the 30º angle results in a slight decrease. The heat transfer enhancement under identical pumping power condition for the attack angle of 30º is larger than that for the attack angle of 45º either for staggered or for aligned tube bank arrangement.

关键词： computational inherent mechanism staggered decrease transfer surface