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废电池-污泥吸附剂的优化制备及对Cr(Ⅵ)的吸附特性 预览
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作者 牛志睿 祁乙浩 +2 位作者 刘羽 史宁 刘强 《环境污染与防治》 CAS CSCD 北大核心 2019年第3期266-269,共4页
以污水处理厂污泥为原料、废电池电极材料和ZnCl2为活化剂,耦合活化制备废电池-污泥吸附剂。利用筛选实验设计中Plackett-Burman和响应曲面法中Box-Behnken实验联用得出优化条件,3次平行实验验证得到制备的最优吸附剂碘吸附值和得率平... 以污水处理厂污泥为原料、废电池电极材料和ZnCl2为活化剂,耦合活化制备废电池-污泥吸附剂。利用筛选实验设计中Plackett-Burman和响应曲面法中Box-Behnken实验联用得出优化条件,3次平行实验验证得到制备的最优吸附剂碘吸附值和得率平均分别为474mg/g、44.8%。Cr(Ⅵ)吸附表明,Langmuir吸附等温模型(R2=0.995 3)和准二级动力学模型(R2=0.999 8)更适合描述该最优吸附剂对Cr(Ⅵ)的吸附行为。 展开更多
关键词 废电池 污泥 吸附剂 制备 Cr(Ⅵ) 吸附
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Zr-Sn-Nb-Fe-V合金包壳管加工过程中第二相的演变 预览
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作者 吴宗佩 易伟 +2 位作者 杨忠波 程竹青 陈波全 《原子能科学技术》 EI CAS CSCD 北大核心 2019年第3期385-391,共7页
采用扫描电子显微镜(SEM)和透射电子显微镜(TEM)研究了Zr-0.2Sn-1.3Nb-0.2Fe-0.05V合金经热挤压、冷轧、中间退火包壳管坯以及经终轧及最终退火后成品管材第二相特征。结果表明,热挤压产生的β-Zr及第二相沿管坯轴向呈流线状分布,随着... 采用扫描电子显微镜(SEM)和透射电子显微镜(TEM)研究了Zr-0.2Sn-1.3Nb-0.2Fe-0.05V合金经热挤压、冷轧、中间退火包壳管坯以及经终轧及最终退火后成品管材第二相特征。结果表明,热挤压产生的β-Zr及第二相沿管坯轴向呈流线状分布,随着冷轧和退火的进行,亚稳相β-Zr发生分解,第二相逐渐均匀化,最终呈细小、均匀、弥散分布。合金成品管材第二相主要为BCC结构的β-Nb,含有少量FCC结构的Zr(NbFeV)2。加工过程中析出相的平均直径变化不大,均小于100 nm。合金包壳管第二相尺寸分布与热处理过程中含Nb第二相溶解析出直接相关。 展开更多
关键词 Zr-Sn-Nb-Fe-V合金 包壳管 加工过程 第二相
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Influence of Precursor Powder Fabrication Methods on the Superconducting Properties of Bi-2223 Tapes
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作者 崔利军 张平祥 +7 位作者 闫果 冯勇 刘向宏 李建峰 潘熙锋 张胜楠 马小波 李金山 《中国物理快报:英文版》 SCIE CAS CSCD 2019年第2期59-63,共5页
Bi-2223 precursor powders are prepared by both oxalate co-precipitation(CP) and spray pyrolysis(SP) methods.The influence of fabrication methods on the superconducting properties of Bi-2223 tapes are systematically st... Bi-2223 precursor powders are prepared by both oxalate co-precipitation(CP) and spray pyrolysis(SP) methods.The influence of fabrication methods on the superconducting properties of Bi-2223 tapes are systematically studied. Compared to the CP method, SP powder exhibits spherical particle before calcination and smaller particle size after calcinations with more uniform chemical composition, which leads to a lower reaction temperature during calcination process for Bi-2223 tapes. Meanwhile, the non-superconducting phases in SP powder are more uniformly distributed with smaller particle sizes. These features result in finer homogeneity of critical current in large-length of Bi-2223 tape, higher density of filaments and better texture after heat treatment. Therefore,the SP method could be considered as a better route to prepare precursor powder for large-length Bi-2223 tape fabrication. 展开更多
关键词 PRECURSOR POWDER FABRICATION Methods SUPERCONDUCTING Properties BI-2223 TAPES
板-锻复合结构加氢反应器的研制
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作者 夏益亮 赵清万 张超 《中国化工装备》 CAS 2019年第2期13-19,共7页
该文介绍了板-锻复合结构加氢反应器的制造及检验过程,分析了设备制造过程中的重、难点,通过一些创新性的工艺手段以及严格的检验过程控制,使设备不仅达到了各项技术指标,还为用户节约了可观的资金,缩短了半年的制造周期,为国内大型加... 该文介绍了板-锻复合结构加氢反应器的制造及检验过程,分析了设备制造过程中的重、难点,通过一些创新性的工艺手段以及严格的检验过程控制,使设备不仅达到了各项技术指标,还为用户节约了可观的资金,缩短了半年的制造周期,为国内大型加氢反应器的制造提供了新的借鉴。 展开更多
关键词 板-锻复合 加氢反应器 制造 焊接 热处理
大型钢结构空间曲面管桁架制作技术探讨 预览
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作者 宋永恒 《建筑技术开发》 2019年第9期12-14,共3页
研究了大跨度异形空间曲面管桁架放样、下料、拼装技术,通过计算机三维建模生成杆件大样图和加工数据,以及胎架三维空间定型数据,解决了复杂的异形曲面管桁架的加工制作难题。利用计算机软件Tekla Structures程序进行三位整体建模,计算... 研究了大跨度异形空间曲面管桁架放样、下料、拼装技术,通过计算机三维建模生成杆件大样图和加工数据,以及胎架三维空间定型数据,解决了复杂的异形曲面管桁架的加工制作难题。利用计算机软件Tekla Structures程序进行三位整体建模,计算机取样,生成数据,数据输入到六维数控相贯线切割机及液压弯管机精确下料,使生产效率制作精度得到大幅度提高。 展开更多
关键词 钢结构 空间曲面 管桁架 制作
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Microscopic pump-probe optical technique to characterize the defect of monolayer transition metal dichalcogenides
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作者 Ying Yu Xiankun Zhang +6 位作者 Zhangkai Zhou Zheng Zhang Yanjun Bao Haofei Xu Limin Lin Yue Zhang Xuehua Wang 《光子学研究:英文版》 CSCD 2019年第7期26-36,共11页
Monolayer transition metal dichalcogenides(TMDs)are ideal materials for atomically thin,flexible optoelec.tronic and catalytic devices.However,their optoelectrical performance such as quantum yield and carrier mobilit... Monolayer transition metal dichalcogenides(TMDs)are ideal materials for atomically thin,flexible optoelec.tronic and catalytic devices.However,their optoelectrical performance such as quantum yield and carrier mobility often shows below theoretical expectations due to the existence of defects.For monolayer TMD-based devices,finding a low-cost,time-efficient, and nondestructive technique to visualize the change of defect distribution in the space domain and the defect-induced change of the carrier's lifetime is vital for optimizing their optoelectronic properties.Here, we propose a microscopic pump-probe technique to map the defect distribution of monolayer TMDs.It is found that there is a linear relationship between transient differential reflection intensity and defect density,suggesting that this technique not only realizes the visualization of the defect distribution but also achieves the quantitative estimation of defect density.Moreover,the carrier lifetime at each point can also be obtained by the technique. The technique used here provides a new route to characterize the defect of monolayer TMDs on the micro-zone, which will hopefiilly guide the fabrication of high-quality two-dimensional (2D) materials and the promotion of optoelectrical performance. 展开更多
关键词 TECHNIQUE MONOLAYER FABRICATION
银纳米线基透明导电薄膜研究进展
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作者 杨星 杜得喜 +2 位作者 谢辉 王悦辉 李晶泽 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2019年第5期1707-1716,共10页
随着电子产品不断向小型化和便携式等方向发展,在柔性衬底上制备薄膜电子器件引起了人们越来越多的关注。其中柔性透明导电薄膜作为电子器件必备部件之一已成为重要的研究方向。传统的氧化铟锡材料因其柔韧性差等问题限制了在柔性器件... 随着电子产品不断向小型化和便携式等方向发展,在柔性衬底上制备薄膜电子器件引起了人们越来越多的关注。其中柔性透明导电薄膜作为电子器件必备部件之一已成为重要的研究方向。传统的氧化铟锡材料因其柔韧性差等问题限制了在柔性器件中应用。银纳米线由于优异的导电导热性、良好的机械稳定性、可接受的价格和氧化物仍具有一定的导电性等特点,被认为是最具潜力替代氧化铟锡的下一代柔性透明导电材料。本文介绍了银纳米线基透明导电薄膜的相关理论和制备方法、以及国内外银纳米线基透明导电薄膜的研究进展,并对未来的发展方向进行了展望。 展开更多
关键词 纳米银线 柔性透明导电薄膜 制备 进展
方柱状IPMC制备与驱动性能的研究 预览
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作者 霍凯 何青松 +2 位作者 尹国校 徐显锐 于敏 《功能材料》 EI CAS CSCD 北大核心 2019年第9期9013-9018,9026共7页
离子型聚合物金属复合物(ionic polymer-metal composites, IPMC)是一种离子型电致动聚合物材料,具有尺寸小、质量轻、驱动电压低、形变量大以及生物兼容性好等众多优点。但传统片状IPMC只能在单一方向上运动的缺点,极大地限制了IPMC的... 离子型聚合物金属复合物(ionic polymer-metal composites, IPMC)是一种离子型电致动聚合物材料,具有尺寸小、质量轻、驱动电压低、形变量大以及生物兼容性好等众多优点。但传统片状IPMC只能在单一方向上运动的缺点,极大地限制了IPMC的应用。因此,通过溶液浇铸和化学镀的方法制备出一种可实现多自由度运动的方柱状IPMC,并对其表面电极进行了SEM观测和驱动性能表征分析。通过对比方柱状IPMC在正弦、方波和直流电压信号下的末端位移和输出力变化情况,发现方柱状IPMC在这3种电压信号驱动下均具有较好的驱动性能,且在直流电压信号下末端位移和输出力最大。通过对方柱状IPMC在不同运动方向的测试结果进行对比分析,探究了方柱状IPMC在介入式手术导管导向装置上应用的可行性。 展开更多
关键词 方柱状IPMC 制备 位移 输出力 导向装置
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Controllable fabrication of self-organized nano-multilayers in copper–carbon films
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作者 王伟奇 吉利 +3 位作者 李红轩 刘晓红 周惠娣 陈建敏 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第3期309-316,共8页
In order to clarify the influence of methane concentration and deposition time on self-organized nano-multilayers,three serial copper-carbon films have been prepared at various methane concentrations with different de... In order to clarify the influence of methane concentration and deposition time on self-organized nano-multilayers,three serial copper-carbon films have been prepared at various methane concentrations with different deposition times using a facile magnetron sputtering deposition system. The ratios of methane concentration(CH4/Ar+CH4) used in the experiments are 20%, 40%, and 60%, and the deposition times are 5 minutes, 20 minutes, and 40 minutes, respectively.Despite the difference in the growth conditions, self-organizing multilayered copper-carbon films are prepared at different deposition times by changing methane concentration. The film composition and microstructure are investigated by x-ray photoelectron spectroscopy(XPS), x-ray diffraction(XRD), field emission scanning electron microscopy(FESEM), and high-resolution transmission electron microscopy(HRTEM). By comparing the composition and microstructure of three serial films, the optimal growth conditions and compositions for self-organizing nano-multilayers in copper-carbon film are acquired. The results demonstrate that the self-organized nano-multilayered structure prefers to form in two conditions during the deposition process. One is that the methane should be curbed at low concentration for long deposition time,and the other condition is that the methane should be controlled at high concentration for short deposition time. In particular, nano-multilayered structure is self-organized in the copper-carbon film with copper concentration of 10-25 at.%.Furthermore, an interesting microstructure transition phenomenon is observed in copper-carbon films, that is, the nanomultilayered structure is gradually replaced by a nano-composite structure with deposition time and finally covered by amorphous carbon. 展开更多
关键词 nano-multilayers SELF-ORGANIZED CONTROLLABLE FABRICATION copper–carbon FILMS
基于硅硅低温直接键合的MEMS打印喷头制作工艺 预览
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作者 翟彦昭 蔡安江 +2 位作者 张栋鹏 韩超 李力 《化工学报》 EI CAS CSCD 北大核心 2019年第3期1220-1226,共7页
针对一种MEMS压电式集成打印喷头复杂腔室结构的加工,提出了一套基于ICP刻蚀结合硅硅低温直接键合的制作工艺。首先通过ICP体硅干法刻蚀工艺分别制作了打印喷头的上下腔室结构,然后将带有上下腔室结构的两硅片进行低温直接键合,形成完... 针对一种MEMS压电式集成打印喷头复杂腔室结构的加工,提出了一套基于ICP刻蚀结合硅硅低温直接键合的制作工艺。首先通过ICP体硅干法刻蚀工艺分别制作了打印喷头的上下腔室结构,然后将带有上下腔室结构的两硅片进行低温直接键合,形成完整的打印喷头腔室。通过对打印喷头上下腔室结构的键合实验研究,进一步探索并验证了硅硅低温直接键合的机理,重点研究了不同活化方法和退火时间对复杂腔室结构键合质量的影响,优化了低温直接键合工艺,为带有复杂三维结构的MEMS器件的制作奠定了工艺基础。测试结果表明,制作完成的MEMS打印喷头具有较高的键合强度,且其腔室流道的完整性和密封性良好。 展开更多
关键词 MEMS 低温直接键合 活化 界面 打印喷头 加工制造
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食品各向异性结构及其仿生构建方法 预览
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作者 赵一果 何君 +2 位作者 孙翠霞 鲁伟 方亚鹏 《中国食品学报》 EI CAS CSCD 北大核心 2019年第6期1-12,共12页
各向异性结构在食品中普遍存在。常见的食品如果蔬、禽肉,基于其原生物体自身组织的有序排列,多含有各向异性结构。传统食品在一般性的加工中,经过揉、捏、挤、压等工艺也会形成一定的各向异性。现有仿生食品的研究中,已涉及基于细胞培... 各向异性结构在食品中普遍存在。常见的食品如果蔬、禽肉,基于其原生物体自身组织的有序排列,多含有各向异性结构。传统食品在一般性的加工中,经过揉、捏、挤、压等工艺也会形成一定的各向异性。现有仿生食品的研究中,已涉及基于细胞培养、纺丝、挤压、定向冷冻、剪切等方法构建的各向异性结构。本文重点阐述现有食品中有代表性的各向异性结构,分析比对基于各向异性结构制备仿生食品的主要构建方法,提出仿生构建的发展方向与重点。 展开更多
关键词 食品结构 各向异性 仿生食品 构建方法
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玩出来的新材料——气凝胶 预览
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作者 潘晶晶 王京阳 《自然杂志》 2019年第4期235-241,共7页
作为一种诞生于20世纪初的材料,气凝胶本不属于最近发现的“新材料”,然而近年来在多个领域的频繁亮相,令公众对这种材料产生了浓厚的兴趣,大呼新奇。与此同时,由于报道角度的不同,这种材料无疑成为了“多面体”,给人以扑朔迷离之感。... 作为一种诞生于20世纪初的材料,气凝胶本不属于最近发现的“新材料”,然而近年来在多个领域的频繁亮相,令公众对这种材料产生了浓厚的兴趣,大呼新奇。与此同时,由于报道角度的不同,这种材料无疑成为了“多面体”,给人以扑朔迷离之感。本文旨在以科普的笔调重塑气凝胶的形象,结合气凝胶的历史浅谈对这种材料的认识,以期澄清疑惑,加深理解。 展开更多
关键词 气凝胶 制备 应用
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Review on nanocomposites fabricated by mechanical alloying 预览
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作者 Mohammed A. Taha Rasha A. Youness M.F. Zawrah 《矿物冶金与材料学报:英文版》 SCIE EI CAS CSCD 2019年第9期1047-1058,共12页
Composites are composed of multiphase materials, where each phase has specific properties that differ from those of the other phases which can effect on the whole properties of composite. Nanocomposites are class of m... Composites are composed of multiphase materials, where each phase has specific properties that differ from those of the other phases which can effect on the whole properties of composite. Nanocomposites are class of materials that contain at least one phase in the nanometric size range and can be produced by any suitable technique for preparing nanomaterials. Composites are an interesting class of materials that have recently been used in numerous applications, including structural, biomedical, electronics, and environmental applications. In composites, reinforcements might be fibers, particulates, or whiskers. Mechanical alloying(MA) is a promising technique for producing nanocomposite materials that are difficult or impossible to prepare via conventional techniques. In this review, we provide an overview of nanocomposites prepared by the MA process. The mechanism of milling and other milling parameters are overviewed, and insights into sintering categories and parameters are also presented. 展开更多
关键词 NANOCOMPOSITES mechanical ALLOYING FABRICATION SINTERING
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Vacuum-free fabrication of high-performance semitransparent perovskite solar cells via e-glue assisted lamination process
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作者 Hengkai Zhang Yaokang Zhang +6 位作者 Guang Yang Zhiwei Ren Wei Yu Dong Shen Chun-Shing Lee Zijian Zheng Gang Li 《中国科学:化学英文版》 SCIE EI CAS CSCD 2019年第7期875-882,共8页
From a base material of conductive polymer(poly-(3,4-ethylenedioxythiophene):poly(styrenesulfonate),PEDOT:PSS),a flexible and high-conductivity(as low as 45Ω/sq)transparent electrode was fabricated on polydimethylsil... From a base material of conductive polymer(poly-(3,4-ethylenedioxythiophene):poly(styrenesulfonate),PEDOT:PSS),a flexible and high-conductivity(as low as 45Ω/sq)transparent electrode was fabricated on polydimethylsiloxane elastomer by an acid treatment and transfer process.Combined with the D-sorbitol-doped PEDOT:PSS electric glue,we successfully demonstrated a vacuum-free and ambient lamination fabrication process for semi-transparent perovskite solar cells using triple cation Cs0.05(MA0.17FA0.83)0.95Pb(I0.83Br0.17)3perovskite.By this manufacturing-friendly lamination process,we fabricated semitransparent perovskite solar cell devices with power conversion efficiencies up to 16.4%and variable transparencies. 展开更多
关键词 PEROVSKITE solar cells LAMINATION electric GLUE semi-transparent vacuum-free fabrication
Wafer-scale MOCVD growth of monolayer M0S2 on sapphire and SiO2
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作者 Huanyao Cun Michal Macha +5 位作者 HoKwon Kim Ke Liu Yanfei Zhao Thomas LaGrange Andras Kis Aleksa ndra Radeno vic 《纳米研究:英文版》 SCIE EI CAS CSCD 2019年第10期2646-2652,共7页
High-quality and large-scale growth of monolayer molybdenum disulfide(MoS2)has caught intensive attention because of its potential in many applications due to unique electronic properties.Here,we report the wafer-scal... High-quality and large-scale growth of monolayer molybdenum disulfide(MoS2)has caught intensive attention because of its potential in many applications due to unique electronic properties.Here,we report the wafer-scale growth of high-quality mono layer MoS2 on singlecrystalline sapphire and also on SiO2 substrates by a facile metal-organic chemical vapor deposit!on(MOCVD)method.Prior to growth,an aqueous solution of sodium molybdate(Na2MoO4)is spun onto the substrates as the molybdenum precursor and diethyl sulfide((C2H5)2S)is used as the sulfur precursor duri ng the growth.The grown MoS2 films exhibit crystal I i nity,good electrical performa nee(electro n mobility of 22 cm2·V^-1·s^-1)and structural continuity maintained over the entire wafer.The sapphire substrates are reusable for subsequent growth.The same method is applied for the synthesis of tungsten disulfide(WS2).Our work provides a facile,reproducible and cost-efficient method for the scalable fabricati on of high-quality mono layer MoS2 for versatile applicati ons,such as electro nic and optoelectr onic devices as well as the membranes for desalination and power generation. 展开更多
关键词 molybdenum disulfide two-dimensional(2D)materials metal-organic chemical vapor deposition(MOCVD) wafer-scale fabrication
The effects of fabrication atmosphere condition on the microstructural and mechanical properties of laser direct manufactured stainless steel 17-4 PH
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作者 D.Wang C.T.Chi +6 位作者 W.Q.Wang Y.L.Li M.S.Wang X.G.Chen Z.H.Chen X.P.Cheng Y.J.Xie 《材料科学技术学报:英文版》 SCIE EI CAS CSCD 2019年第7期1315-1322,共8页
The effects of atmosphere conditions on microstructural and mechanical properties of stainless steel 17-4PH components fabricated by laser direct manufacturing (LDM) were investigated through mea-surements on phase co... The effects of atmosphere conditions on microstructural and mechanical properties of stainless steel 17-4PH components fabricated by laser direct manufacturing (LDM) were investigated through mea-surements on phase constitution, porosity, tensile strength, fracture morphology, hardness and evolution of substrate temperature. Results showed that the samples produced in air atmosphere condition pos-sessed higher tensile strength and hardness for both as-deposited and heat-treated states than that in Ar chamber condition, due to dispersion strengthening effect of amorphous oxide particles and nitrogen solution strengthening as a result of higher content of oxygen and nitrogen. The temperature of substrate heat accumulation was higher in Ar chamber condition, leading to dramatically lower porosity and more reverse austenite, which also contributed to the lower strength and hardness. 展开更多
关键词 Additive MANUFACTURING LASER DIRECT MANUFACTURING 17-4 PH stainless steel FABRICATION ATMOSPHERE MECHANICAL properties
BIM与RFID技术在装配式综合管廊中的应用研究 预览
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作者 杨志勇 章沛蓉 +1 位作者 张雨杰 张文时 《城市道桥与防洪》 2019年第8期259-262,M0029共5页
随着国家大力发展装配式建筑,装配式综合管廊工作成效明显。但是,在实际工程中,装配式综合管廊建造仍然存在问题:(1)设计管廊钢筋与预制不符,工业化厂需对施工图深化设计;(2)工业化生产时,预埋件易错漏;(3)施工现场管廊构件管理混乱,影... 随着国家大力发展装配式建筑,装配式综合管廊工作成效明显。但是,在实际工程中,装配式综合管廊建造仍然存在问题:(1)设计管廊钢筋与预制不符,工业化厂需对施工图深化设计;(2)工业化生产时,预埋件易错漏;(3)施工现场管廊构件管理混乱,影响吊装,甚至出现拼接错误;(4)管廊舱内附属设施安装时,无法准确定位预埋件。针对上述问题,将BIM与RFID技术结合,建立BIM模型与预制管廊的联动系统,实现了装配式综合管廊的智能化设计、生产、施工和运营管理。 展开更多
关键词 BIM RFID 综合管廊 装配 智能化
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Fabrication and Characterization of GaN-Based Micro-LEDs on Silicon Substrate
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作者 王琦 余俊驰 +8 位作者 陶涛 刘斌 智婷 岑旭 谢自力 修向前 周玉刚 郑有炓 张荣 《中国物理快报:英文版》 SCIE CAS CSCD 2019年第8期94-97,共4页
GaN-based micro light emitting diodes(micro-LEDs) on silicon(Si)substrates with 40μm in diameter are developed utilizing standard photolithography and inductively coupled plasma etching techniques.From currentvoltage... GaN-based micro light emitting diodes(micro-LEDs) on silicon(Si)substrates with 40μm in diameter are developed utilizing standard photolithography and inductively coupled plasma etching techniques.From currentvoltage curves,the relatively low turn-on voltage of 2.8 V and low reverse leakage current in the order of 10-8 A/cm2 indicate good electrical characteristics.As the injection current increases,the electroluminescence emission wavelength hardly shifts at around 433 nm, and the relative external quantum efficiency slightly decays,because the impact of quantum-confined Stark effect is not serious in violet-blue micro-LEDs.Since GaN-LEDs are cost effective on large-area Si and suitable for substrate transfer or vertical device structures,the fabricated micro-LEDs on Si should have promising applications in the fields of high-resolution display and optical communication. 展开更多
关键词 FABRICATION CHARACTERIZATION SILICON
340GHz倒圆角交错双栅行波管的仿真与冷测 预览
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作者 邵伟 田瀚文 +6 位作者 王战亮 唐涛 巩华荣 段兆云 魏彦玉 冯进军 宫玉彬 《红外与毫米波学报》 SCIE EI CAS CSCD 北大核心 2019年第3期303-309,共7页
近些年来交错双栅行波管由于其高功率容量和易加工等优点受到了很多的关注.然而随着器件工作频率的升高尤其对于太赫兹频段结构的损耗严重限制了行波管的性能.本文考虑了损耗和加工所导致的圆角等因素针对交错双栅结构提出了一个更切实... 近些年来交错双栅行波管由于其高功率容量和易加工等优点受到了很多的关注.然而随着器件工作频率的升高尤其对于太赫兹频段结构的损耗严重限制了行波管的性能.本文考虑了损耗和加工所导致的圆角等因素针对交错双栅结构提出了一个更切实际的设计.仿真结果表明该行波管在 320 ~342 GHz 频率范围内能获得大于 5 W 的输出功率.采用了相速跳变方法来提高输出功率在整个工作频带内输出功率都得到了大于28%的提升.在此基础上加工了340GHz交错双栅慢波结构并开展了冷测实验在330~360GHz范围内盒型窗的S21测试结果大于-2.1dB且电压驻波比在334~355GHz范围内小于1.35.同时对包含盒型窗部件的高频系统进行了冷测其电压驻波比测试结果在 335 ~344 GHz 范围内均小于 2 且该冷测结果与仿真结果之间趋势基本一致. 展开更多
关键词 倒圆角的交错双栅 行波管 损耗 加工 盒型窗 相速跳变
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Nanoliter liquid refractive index sensing using a silica V-groove fiber interferometer
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作者 Quan Chai Hyeonwoo Lee +4 位作者 Seongjin Hong Yongsoo Lee Junbum Park Jianzhong Zhang Kyunghwan Oh 《光子学研究:英文版》 CSCD 2019年第7期107-112,共6页
A unique all-fiber interferometric sensor was proposed and successfully demonstrated efficient low-refractiveindex liquid sensing in the range from 1.33 to 1.37, which is compatible with those of bio-liquids.A special... A unique all-fiber interferometric sensor was proposed and successfully demonstrated efficient low-refractiveindex liquid sensing in the range from 1.33 to 1.37, which is compatible with those of bio-liquids.A special silica coreless optical fiber with an open V-groove was used as an optical sensing medium, which provided a high sensitivity for a minute liquid volume in the nanoliter scale.The V-groove fiber (VGF) was serially concatenated between two single-mode fibers (SMFs).The LPOi mode guided along the input SMF excited the higherorder inodes in the VGF to generate multimode interference,whose spectrum was transmitted through the output SMF. A single liquid droplet with volume of ~80 nanoliters wet the entire hydrophilic surface of the VGF, and the transmission spectra shifted corresponding to its refractive index in a very linear manner. The sensor also showed a negligible temperature cross-sensitivity in the range 25℃-75℃, which overlaps with the biological temperature window such that the sensitivity of 159.696 nm per refractive index unit(nm/RIU) remained independent of the temperature variation. Modal properties of VGF were thoroughly analyzed numerically, and detailed processes for the sensor fabrication and sensing experiments were reported. 展开更多
关键词 INTERFEROMETER PROCESSES FABRICATION
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