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带有双参数的不确定年龄更新策略 预览
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作者 罗倩 张春晓 +3 位作者 龙棋 黄丽娟 裘佳峰 李强 《科技创新导报》 2019年第7期10-14,共5页
本文针对新型飞机零部件缺乏历史运营数据的问题,将零部件寿命设为不确定变量,研究了带有双参数的不确定年龄更新策略。以长期意义下平均维修成本最小为目标,建立了寻求最优年龄更新周期的不确定规划模型。最后,数值算例及敏感性分析结... 本文针对新型飞机零部件缺乏历史运营数据的问题,将零部件寿命设为不确定变量,研究了带有双参数的不确定年龄更新策略。以长期意义下平均维修成本最小为目标,建立了寻求最优年龄更新周期的不确定规划模型。最后,数值算例及敏感性分析结果验证了模型的有效性。 展开更多
关键词 零部件寿命 双参数 年龄更新策略 不确定规划模型
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Cubosome nanoparticles for enhanced delivery of mitochondria anticancer drug elesclomol and therapeutic monitoring via sub-cellular NAD(P) H multi-photon fluorescence lifetime imaging
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作者 Ana R.Faria Oscar F.Silvestre +3 位作者 Christian Maibohm Ricardo M.R.Adao Bruno F.B.Silva Jana B.Nieder 《纳米研究:英文版》 SCIE EI CAS CSCD 2019年第5期991-998,共8页
Elesclomol (ELC) is an anticancer drug inducing mitochondria cytotoxicity through reactive oxygen species.Here,for the first time,we encapsulate the poorly water soluble ELC in monoolein-based cubosomes stabilized wit... Elesclomol (ELC) is an anticancer drug inducing mitochondria cytotoxicity through reactive oxygen species.Here,for the first time,we encapsulate the poorly water soluble ELC in monoolein-based cubosomes stabilized with Pluronic F127.Cellular uptake and nanocarrier accumulation close to the mitochondria with sub-micrometer distance is identified via three-dimensional (3D) confocal microscopy and edge-to-edge compartment analysis.To monitor the therapeutic effect of the ELC nanocarrier,we apply for the first time,label-free time-lapse multi-photon fluorescence lifetime imaging microscopy (MP-FLIM) to track NAD(P)H cofactors with sub-cellular resolution on live cells exposed to an anticancer nanocarrier.Improved in vitro cytotoxicity is verified when loading the pre-complexed ELC with copper (ELC-Cu).Importantly,for equivalent copper concentration,cubosomes loaded with ELC-Cu show higher cytotoxicity compared to the free drug.The novel nanocarrier shows promising features for systemic ELC-Cu administration,and furthermore we establish the MP-FLIM technique for the assessment of anticancer drug delivery systems. 展开更多
关键词 CUBOSOMES mitoch on dria reactive oxyge n species elesclomol NAD(P)H fluoresce NEE lifetime ANTICANCER therapy
Quantal studies of sodium 3p ← 3s photoabsorption spectra perturbed by ground lithium atoms
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作者 N Lamoudi F Talbi +2 位作者 M T Bouazza M Bouledroua K Alioua 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第6期146-154,共9页
The pressure broadening in the far wings, where the sodium Na(3 p ← 3 s) resonance line is perturbed by ground lithium Li(2 s) atoms, has been theoretically analyzed. The NaLi potential–energy curves and the transit... The pressure broadening in the far wings, where the sodium Na(3 p ← 3 s) resonance line is perturbed by ground lithium Li(2 s) atoms, has been theoretically analyzed. The NaLi potential–energy curves and the transition dipole moments are constructed by using a reliable ab initio data points to carry out the reduced-absorption coefficients k_r(ν, T). This quantum-mechanical investigation have demonstrated that the NaLi profile spectra show a satellite future in the red wing at wavelength λ = 685 nm in the temperature range 4000 K–1.8 × 10~4 K. The computation could also exhibit a second satellite, in the blue wing, near the wavelength λ = 574 nm beyond 6000 K and a third peak located at λ = 490 nm which begins to appear at 1.8 × 10~4 K. 展开更多
关键词 pressure BROADENING absorption COEFFICIENT satellite structure RADIATIVE LIFETIME
Fluorescence lifetime based distance measurement illustrates conformation changes of PYL10-CL2 upon ABA binding in solution state
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作者 Peng Zhou Pei Lv +3 位作者 Lu Yu Sanling Liu Longhua Zhang Changlin Tian 《中国化学快报:英文版》 SCIE CAS CSCD 2019年第5期1067-1070,共4页
Forster resonance energy transfer(FRET)is a widely used distance measurement method to illustrate protein conformational dynamics.The FRET method relies on the distance between donor and acceptor,as well as the labell... Forster resonance energy transfer(FRET)is a widely used distance measurement method to illustrate protein conformational dynamics.The FRET method relies on the distance between donor and acceptor,as well as the labelling efficiency,the size and the properties of the fluorophores.Here,we labelled a pair of small fluorophores and calculated the energy transferred efficiency through fluorescence lifetime analysis,which can provide more reliable distance measurement than intensity attenuation.The donor fluorophore,7-hydroxycoumarin-4-yl-ethylglycine(HC),was genetically incorporated into specific sites of PYL10,obtaining complete labelling efficiency.The acceptor fluorophore,Alexa488,was labelled through the disulfide bond,whose labelling efficiency was estimated through both absorption peaks and lifetime populations.Fluorescence lifetime and anisotropy analysis showed ABA-induced local conformation changes and dynamics of several HC incorporation sites of PYL10.The lifetime-based FRET distance measurement illustrated the conformation changes of PYL10 with or without ABA application,which is consistent with the previously reported crystal structures. 展开更多
关键词 Fluorescence LIFETIME ANISOTROPY Unnatural AMINO acid PYL10 DISTANCE measurement
Zn^2+对铅中毒果蝇生育力、寿命及抗氧化能力的影响 预览
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作者 叶文斌 王昱 +3 位作者 王瀚 杨小录 何九军 王让军 《化学与生物工程》 CAS 2019年第2期55-61,共7页
以果蝇为实验动物,探讨了不同浓度的Zn2+对铅中毒果蝇生育力和寿命的影响,并以SOD活性、CAT活性、MDA含量为指标评价其抗氧化能力。结果表明,1.0×10^-3g·mL^-1Zn^2+对铅中毒果蝇的生育力有较好的促进作用,能消减对雄性果蝇生... 以果蝇为实验动物,探讨了不同浓度的Zn2+对铅中毒果蝇生育力和寿命的影响,并以SOD活性、CAT活性、MDA含量为指标评价其抗氧化能力。结果表明,1.0×10^-3g·mL^-1Zn^2+对铅中毒果蝇的生育力有较好的促进作用,能消减对雄性果蝇生殖细胞的毒害作用;对铅中毒果蝇的寿命也有明显的延长作用;同时减缓了铅中毒果蝇体内SOD和CAT活性的降低,降低了MDA含量,提高了铅中毒果蝇的抗氧化能力。 展开更多
关键词 ZN^2+ 铅中毒 果蝇 生育力 寿命 抗氧化能力
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Room-temperature continuous-wave operation of GaN-based blue-violet laser diodes with a lifetime longer than 1000h 预览
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作者 Feng Liang Jing Yang +9 位作者 Degang Zhao Zongshun Liu Jianjun Zhu Ping Chen Desheng Jiang Yongsheng Shi Hai Wang Lihong Duan Liqun Zhang Hui Yang 《半导体学报:英文版》 EI CAS CSCD 2019年第2期39-42,共4页
GaN-based continuous-wave operated blue-violet laser diodes(LDs) with long lifetime are demonstrated, which are grown on a c-plane GaN substrate by metal organic chemical vapor deposition with a 10 × 600 μm~2 ri... GaN-based continuous-wave operated blue-violet laser diodes(LDs) with long lifetime are demonstrated, which are grown on a c-plane GaN substrate by metal organic chemical vapor deposition with a 10 × 600 μm~2 ridge waveguide structure.The electrical and optical characteristics of a blue-violet LD are investigated under direct-current injection at room temperature(25 °C). The stimulated emission wavelength and peak optical power of the LD are around 413 nm and over 600 mW, respectively.In addition, the threshold current density and voltage are as small as 1.46 kA/cm~2 and 4.1 V, respectively. Moreover, the lifetime is longer than 1000 hours under room-temperature continuous-wave operation. 展开更多
关键词 GAN-BASED blue-violet laser DIODES long LIFETIME THRESHOLD voltage
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21世纪以来陆机研究述评 预览
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作者 陈璐 《唐都学刊》 2019年第3期72-77,共6页
21世纪以来,陆机研究成果甚为丰厚,研究者不仅在内容、手法、风格等方面有探讨,还从地域、士风、儒学、哲学、抒情方式等方面进行多角度探索,既有理论建构,也有诗艺分析,还有地位评价。可见,《文赋》仍然是陆机研究的重点和难点,其他则... 21世纪以来,陆机研究成果甚为丰厚,研究者不仅在内容、手法、风格等方面有探讨,还从地域、士风、儒学、哲学、抒情方式等方面进行多角度探索,既有理论建构,也有诗艺分析,还有地位评价。可见,《文赋》仍然是陆机研究的重点和难点,其他则集中在陆机生平考辨和诗歌研究。同时,也存在一些问题,如陆机生平仍无定论,辞赋和散文研究比较薄弱,接受史研究仍为空白。在此情况下,应加强辞赋与散文研究,并进行陆机接受史的疏理,推动现有陆机研究。 展开更多
关键词 21世纪 陆机 生平 《文赋》 作品
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全钒液流电池离子传导膜研究进展
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作者 赵丽娜 肖伟 +1 位作者 刘建国 严川伟 《化工新型材料》 CAS CSCD 北大核心 2019年第5期227-230,共4页
全钒液流电池(VFB)作为大容量、快速充放电、高效率的液流储能电池,是满足风能、太阳能发电及智能电网对大规模储能需求的一种理想储能装置。作为VFB的关键功能材料之一,离子传导膜既起到分隔正负极、防止电池短路的作用,又具备电荷载... 全钒液流电池(VFB)作为大容量、快速充放电、高效率的液流储能电池,是满足风能、太阳能发电及智能电网对大规模储能需求的一种理想储能装置。作为VFB的关键功能材料之一,离子传导膜既起到分隔正负极、防止电池短路的作用,又具备电荷载体的传导功能。介绍了VFB的工作原理及商业化离子传导膜的研究应用现状,对比分析了非氟离子传导膜实现电荷载体传导功能的改性方法,为新型离子传导膜的设计提供科学基础。 展开更多
关键词 全钒液流电池 离子传导膜 电导率 离子渗透 寿命
Synthesis and optical properties of LiNd(PO3)4 nanocrystals dispersion in DMSO/TBE
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作者 Zhongyue Wang Zhen Yang +4 位作者 Ruilin Zheng Kehan Yu Peng Lv Chunxiao Liu Wei Wei 《中国稀土学报:英文版》 SCIE EI CAS CSCD 2019年第6期580-584,共5页
Lanthanide doped nanocrystals with strong fluorescence, long lifetime at high doping concentrations have great potential application in bio-imaging and liquid gain medium. LiNd(PO3)4(LNP) crystal was reported to be on... Lanthanide doped nanocrystals with strong fluorescence, long lifetime at high doping concentrations have great potential application in bio-imaging and liquid gain medium. LiNd(PO3)4(LNP) crystal was reported to be one of the most excellent laser crystals with high Nd3+ concentration, and their nanocrystals synthesized via improved combustion method for the first time had strong emission intensity and long fluorescence lifetime of 122 μs. Besides,LiNd(PO3)4 nanocrystals can be dispersed in mixed solvents of DMSO/TBE(CHBr2 CHBr2) to form a transparent colloidal dispersion, and Judd-Ofelt theory was used to evaluate their optical parameters. In summary, LiNd(PO3)4 nanocrystals possess long lifetime(116 μs), low solvents quenching rate(4.9%), large emission cross section(7.63 × 10-20 cm2) and high quantum yield(35.2%) under high Nd3+ ions concentration(1×1020 cm-3), which would be the most competitive colloidal gain medium of optical amplification and laser with LD pump and potential biomaterial with low particles concentration. 展开更多
关键词 LNP Index-matching MATCHING Fluorescence LIFETIME High quantum YIELD Rare earths
带有重叠区域的多跳非均匀分簇路由算法
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作者 牛玉刚 周振华 《控制与决策》 EI CSCD 北大核心 2019年第6期1271-1276,共6页
能耗作为衡量无线传感器网络性能的一项重要指标,通常将延长生命周期、均衡能耗作为网络协议重要的设计目标.针对静态、异构、非均匀分布的网络模型,设计带有重叠区域的分簇及簇内单跳、簇间多跳的路由算法—–OMU分簇路由算法,该算法... 能耗作为衡量无线传感器网络性能的一项重要指标,通常将延长生命周期、均衡能耗作为网络协议重要的设计目标.针对静态、异构、非均匀分布的网络模型,设计带有重叠区域的分簇及簇内单跳、簇间多跳的路由算法—–OMU分簇路由算法,该算法中簇头不再作为数据转发节点,而主要用于簇内数据的接收与融合.通过综合考虑节点剩余能量、节点密度及与基站的距离进行簇头选举并进行分簇,形成簇间重叠区域,产生用于数据转发的中继节点.同时,建立簇头与中继节点轮换机制以达到节点能耗均衡的目的,并为每个节点建立能量最省的多跳数据传输路径.仿真结果表明,所设计的分簇路由算法,特别是在大规模部署的无线传感器网络中,能有效减少和均衡能量消耗. 展开更多
关键词 无线传感器网络 非均匀分簇 重叠区域 多跳路由 生命周期 能耗均衡
伦明生平及其学术成就述略 预览
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作者 钱昆 《山东图书馆学刊》 2019年第3期38-42,48共6页
东莞图书馆整理的《伦明全集》(一至五册)成功付梓,对东莞地方乡贤文献的整理与研究极具意义。笔者在此基础上进一步爬梳资料,对伦明的生平按其人生发展的六大阶段进行归纳整理,相对清晰地展现伦明的一生,并对伦明的学术成就概括总结,... 东莞图书馆整理的《伦明全集》(一至五册)成功付梓,对东莞地方乡贤文献的整理与研究极具意义。笔者在此基础上进一步爬梳资料,对伦明的生平按其人生发展的六大阶段进行归纳整理,相对清晰地展现伦明的一生,并对伦明的学术成就概括总结,包括诗歌创作和文献学两个领域。 展开更多
关键词 伦明 生平 诗歌创作 文献学
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基于非合作博弈的无线传感器网络覆盖控制算法 预览
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作者 刘浩然 赵赫瑶 +2 位作者 邓玉静 王星淇 尹荣荣 《通信学报》 EI CSCD 北大核心 2019年第1期71-78,共8页
针对节点覆盖冗余造成能量效率低的问题,基于非合作博弈理论,考虑节点覆盖率和剩余能量这2个关键因素构建收益函数,将节点生命周期和网络路径增益等性能参数融入收益函数中,使每个节点选择合适的工作策略来构建网络拓扑,提出一种基于非... 针对节点覆盖冗余造成能量效率低的问题,基于非合作博弈理论,考虑节点覆盖率和剩余能量这2个关键因素构建收益函数,将节点生命周期和网络路径增益等性能参数融入收益函数中,使每个节点选择合适的工作策略来构建网络拓扑,提出一种基于非合作博弈理论的无线传感器网络覆盖控制算法。理论证明节点覆盖率和剩余能量之间存在纳什均衡,且收益函数收敛于帕累托最优。仿真结果表明,该算法能够提供合理的网络节点覆盖率并保证能量效率。 展开更多
关键词 非合作博弈 无线传感器网络 覆盖率 生命周期
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Transplantation of adult spinal cord tissue: Transection spinal cord repair and potential clinical translation
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作者 Hang Lin 《中国科学:生命科学英文版》 SCIE CAS CSCD 2019年第6期870-872,共3页
Spinal cord injury (SCI), often resulting from car accidents,falls and violence, represents a complicated trauma affecting multiple tissues, such as the vertebrate, disks of the spinal column, or the spinal cord itsel... Spinal cord injury (SCI), often resulting from car accidents,falls and violence, represents a complicated trauma affecting multiple tissues, such as the vertebrate, disks of the spinal column, or the spinal cord itself. Direct injury to the spinal cord, which is the focus of this insight, may disrupt the neuronal connections between the brain and the periphery,leading to the loss of motor function and paralysis. Consequently, SCI patients suffer neurologic deficits and disability,and are subjected to high healthcare costs for a lifetime. 展开更多
关键词 SPINAL CORD injury car accidents COSTS for a LIFETIME
多维度下教师教育一体化发展的全然性研究 预览
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作者 郭娜 《安徽警官职业学院学报》 2019年第1期124-128,共5页
从“师范教育”到“教师教育”的改变,体现了教师培养过程的深刻变革。教育要兴,关键在师,教育发展的内在动力是教师,因此对教师的教育显得尤为重要。教师的培养离不开教师教育的发展和进步。为此,要从教师这一职业和教师角色这两个方... 从“师范教育”到“教师教育”的改变,体现了教师培养过程的深刻变革。教育要兴,关键在师,教育发展的内在动力是教师,因此对教师的教育显得尤为重要。教师的培养离不开教师教育的发展和进步。为此,要从教师这一职业和教师角色这两个方面正视教师职业的专门性,明确教师职业的不可替代性,强化教师职业的师范性。从根本上转变观念:一名教师的长成不再只是师范院校师范专业的短期任务,而是作为一名教师自身发展的长期需要。 展开更多
关键词 教师教育 专门性 师范性 终身
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溶液表面张力对反气泡稳定时间的影响 预览
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作者 安骥 王鑫 +1 位作者 何随龙 郑洪 《液压气动与密封》 2019年第4期34-38,共5页
反气泡是产生于液体中并由一层气膜包裹液珠的特殊结构。影响反气泡稳定性的因素有温度、压强、电解质浓度、溶液黏度等,除此之外表面张力也是重要因素之一。通过实验发现,溶液表面张力的变化而变化的情况,当溶液的表面张力小于47mN/m时... 反气泡是产生于液体中并由一层气膜包裹液珠的特殊结构。影响反气泡稳定性的因素有温度、压强、电解质浓度、溶液黏度等,除此之外表面张力也是重要因素之一。通过实验发现,溶液表面张力的变化而变化的情况,当溶液的表面张力小于47mN/m时,溶液开始产生反气泡;当溶液的表面张力在47~35mN/m范围内时,反气泡稳定时间随表面张力减小而增大;当表面张力在35~34mN/m范围内时,反气泡稳定时间随表面张力减小而减小;当表面张力小于34mN/m时,反气泡稳定时间趋于稳定。 展开更多
关键词 反气泡 表面张力 稳定时间 影响
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Synthesis, Crystal Structure and Fluorescence Properties of a Terbium(Ⅲ) Complex with Biphenyl-2,3,3',5'-tetracarboxylic Acid 预览
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作者 李荣芳 朱鑫鑫) +2 位作者 刘新芳 冯勋 王利亚 《结构化学》 SCIE CAS CSCD 2019年第6期985-990,共6页
A new terbium complex based on biphenyl-2,3,3’,5’-tetracarboxylic acid(H4bptc) has been synthesized, {[Tb(Hbptc)(H2O)4]×H2O}n(1). Its structure was determined by single-crystal X-ray diffraction analysis and fu... A new terbium complex based on biphenyl-2,3,3’,5’-tetracarboxylic acid(H4bptc) has been synthesized, {[Tb(Hbptc)(H2O)4]×H2O}n(1). Its structure was determined by single-crystal X-ray diffraction analysis and further characterized by elemental analysis, IR spectra and TG analyses. Title complex crystallizes in monoclinic, space group P21/n with a = 14.090(2), b = 8.0824(13), c = 15.5591(17) A, V = 1775.4(5) A3, Mr = 576.22, Dc = 2.156 g/cm3, μ(Mo Kα) = 4.059 mm-1, F(000) = 1128, Z = 4, the final R = 0.027 and w R = 0.0726 for 3296 observed reflections(I > 2σ(I)). Complex 1 exhibits a 2 D layer structure, and such layers are further united together into a three-dimensional supramolecular structure through π···π interaction and intricate hydrogen bonding. The fluorescence excitation and emission spectroscopy of 1 showed that H4 bptc is a kind of highly efficient sensitizer for terbium(Ⅲ) ion. The title complex also displays efficient ligand sensitized luminescence in the visible region with long lifetime of 2.02 ms in the solid state. 展开更多
关键词 terbium(Ⅲ)complex π…πinteraction luminescence FLUORESCENCE lifetime
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Rules for Amalgamating the Reliability of Elements of Powertrain Systems at Maintenance 预览
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作者 S.V.Belodedenko V.I.Hanush О.M.Hrechanyi 《机械工程与自动化:英文版》 2019年第1期24-32,共9页
The amalgamation procedure is actual when using structural methods of reliability.This may apply as the case of the action of a complex of damaging processes on a structural element and the case of the action of a cer... The amalgamation procedure is actual when using structural methods of reliability.This may apply as the case of the action of a complex of damaging processes on a structural element and the case of the action of a certain damaging process on a system of elements.Classical methods of reliability are poorly adapted for powertrain mechanical systems with a series structural scheme of elements subjected to the gradual influence of several degradation processes.The problem of amalgamation of individual indicators is exacerbated at the stage of operation when diagnosing the technical state of the mechanical system.The application of the classical rule of amalgamation by multiplying the probabilities of survival leads to the effect of over-maintenance.New rules of amalgamation have been developed,which deprive the assessment of the reliability of excessive conservatism.The complex index of the technical condition is offered—the resource safety index(RSI).Its use determines the remaining lifetime.The algorithm for searching the RSI contains an assessment of the criticality of the failure.The search of RSI under the influence of the complex of damaging processes on the element of the powertrain system is demonstrated.The efficiency of the RSI method is shown by the example of the reliability assessment of aircraft bolts.Application of the RSI method increases the guaranteed lifetime by 4-10 times compared with traditional methods. 展开更多
关键词 RELIABILITY indices POWERTRAIN units maintenance RESOURCE LIFETIME RISK
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多晶硅材料特性对太阳能电池效率的影响 预览
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作者 刘林华 马玉英 任现坤 《当代化工》 CAS 2019年第6期1140-1143,共4页
研究了太阳能电池生产工艺中多晶硅片的电阻率、小方锭少子寿命及铸锭区域对电池转化效率的影响。以P型多晶硅片为原材料,通过常规晶硅电池制作工艺,对不同电阻率范围的硅片产出电池片性能进行测试分析;采用少子寿命分别为LT<5.5μs... 研究了太阳能电池生产工艺中多晶硅片的电阻率、小方锭少子寿命及铸锭区域对电池转化效率的影响。以P型多晶硅片为原材料,通过常规晶硅电池制作工艺,对不同电阻率范围的硅片产出电池片性能进行测试分析;采用少子寿命分别为LT<5.5μs、LT>6.0μs的小方锭,统计产出硅片的少子寿命和电阻率,并对比分析产出电池片性能;对比多晶硅铸锭各区域硅片产出电池片的电性能。研究表明,1.4~2.0Ω·cm为多晶硅电池制作的最优电阻率范围;方锭少子寿命>6.0μs的硅片少子寿命与电阻率的平均值都高于方锭少子寿命<5.5μs的硅片,电池转化效率同比高0.07%;铸锭中心区域的硅片产出电池片的转化效率要高于边角区域。 展开更多
关键词 多晶硅 太阳能电池 电阻率 少子寿命 铸锭区域
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Lifetime maximization via joint channel and power assignment for incremental-relay multi-channel systems
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作者 Lihua PANG Yang ZHANG +3 位作者 Ruiyu HAN Kaiyang BAI Guangliang REN Jiandong LI 《中国科学:信息科学(英文版)》 SCIE EI CSCD 2019年第2期115-126,共12页
A comprehensive resource optimization framework is designed for incremental amplify-andforward orthogonal frequency division multiplexing(AF-OFDM)relaying systems to maximize the network lifetime.Specifically,joint ch... A comprehensive resource optimization framework is designed for incremental amplify-andforward orthogonal frequency division multiplexing(AF-OFDM)relaying systems to maximize the network lifetime.Specifically,joint channel and power assignment,i.e.,all degrees of freedom such as incremental policy,channel pairing,relay selection,and power allocation,are optimized with quality of service(QoS)constraints.The lifetime maximization problem is formulated as a mixed-integer nonlinear programming which at first glance seems mathematically intractable.However,a two-nested search loop,in which the outer loop varies the lifetime based on bisection criterion until finding the optimum while the inner loop attempts to derive the corresponding feasible solution set for that given lifetime by employing dual decomposition and subgradient techniques,is then presented to solve it.Numerical results are shown to verify the near-optimality and the effectiveness of our proposal. 展开更多
关键词 lifetime MAXIMIZATION INCREMENTAL relaying AMPLIFY-AND-FORWARD MULTI-CHANNEL SYSTEMS resource OPTIM ization
YAG晶体切割参数对线锯寿命影响的试验研究 预览
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作者 张艳菊 闫军喜 +2 位作者 丁舟波 于贺春 尚会超 《制造技术与机床》 北大核心 2019年第7期94-99,共6页
YAG(Y3Al5O12)晶体以优异的特性正被广泛使用,选择合适的切割方式来降低其加工成本十分重要。对固结线锯的种类和失效形式进行总结,环形电镀多丝绞合金刚石线锯适合硬脆YAG晶体切割。采用往复线机床和环线机床进行切割试验,发现往复线... YAG(Y3Al5O12)晶体以优异的特性正被广泛使用,选择合适的切割方式来降低其加工成本十分重要。对固结线锯的种类和失效形式进行总结,环形电镀多丝绞合金刚石线锯适合硬脆YAG晶体切割。采用往复线机床和环线机床进行切割试验,发现往复线金刚石线锯机床切割线锯寿命短,切割过程易发生断线,环形线锯切割时无换向可实现高速切割。通过环线机床正交试验发现切割线速度提高线锯寿命显著增加,线锯进给速度增加则寿命先提高后降低,线锯张紧力对线锯寿命没有影响。 展开更多
关键词 金刚石线锯 寿命 YAG晶体 正交试验
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