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Dependence of 1.54 μm Photoluminescence on Excess-Si Degrees of Er-Doped Si-Rich SiO_(2) Films Deposited by Magnetron Sputtering

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Chinese Physics Letters 2001年第7期18卷 986-988页

作者： RAN Guang-Zhao CHEN Yuan MA Zhen-Chang ZONG Wan-Hua XIE Li-qing guo Chun-gang qin guo-gang Department of Physics Peking UniversityBeijing 100871 National Key Laboratory for ASIC Hebei Semiconductor Research InstituteShijiazhuang 050051 Key Laboratory in University for Radiation Beam Technology and Materials Modification Beijing Normal UniversityBeijing 100875 International Center for Materials Physics Chinese Academy of SciencesShenyang 110015

Room-temperature 1.54-μm photoluminescence(PL)is observed from Er-doped Si-rich SiO_(2)(SiO_(2):Si:Er)films deposited by using the magnetron sputtering *** determine the optimum Si content in the SiO_(2):Si:Er films,the percentage area of the Si target in the composite SiO_(2)-Si-Er target was changed from 0,to 10%,20%and 30%.The percentage area of the Er target was fixed at 1%.It is found that the optimum annealing temperatures for Er3+luminescence intensities are 900°C for the SiO_(2):Er film and 900,800,and 700°C for the SiO_(2):Si:Er films containing 10%,20%and 30%excess-Si(percentage areas of Si target),*** SiO_(2):Si:Er film containing 20%excess-Si and annealed at 800°C has the intensest PL.

关键词： technique. optimum film

Pho to luminescence and Photoluminescence Excitation of Si Aerogels Prepared by Supercritical Drying

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Chinese Physics Letters 1996年第1期13卷 62-64页

作者： guo guo-lin XU Dong-sheng YAO Guang-qing TANG You-qi ZHANG Li-dong LIN Jun MA Shu-yi DUAN Jia-qi ZHANG Bo-rui qin guo-gang Department of Chemistry Peking UniversityBeijing 100871 Department of Physics Peking UniversityBeijing 100871

Si aerogel,the porous silicon with ultra high porosity,has been prepared by the technique of anodization followed by supercritical *** photoluminescence,photoluminescence excitation and morphological features exhibit novel characteristics from those of the conventionally anodized porous *** observed the differences between the Si aerogels made&om(100)and(111)crystalline Si.

关键词： porous excitation porosity

Electroluminescence from Indium Tin Oxide Film/Nanoscale Si Oxide/p-Si Structure

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Chinese Physics Letters 1999年第8期16卷 605-607页

作者： WANG Yong-qiang ZHAO Tai-ping CUI Xiao-ming MA Zhen-chang ZONG Wan-hua qin guo-gang Department of Physics Peking UniversityBeijing 100871 The 13th Institute of Ministry of Electronic Industry Shijiazhuang 050051 International Center for Material Physics Chinese Academy of SciencesShenyang 110015

After an Si oxide layer of 3nm thickness had been grown by using magnetron sputtering on a p-type Si(100)substrate,an indium tin oxide(ITO)film was deposited onto the Si oxide layer by using electron beam ***(EL)from such an ITO/Si oxide/p-type Si structure was measured under a forward bias of 5V or *** EL power efficiency is about eight times as large as that of a semitransparent Au/Si oxide(3nm)/p-Si *** experimental results indicate that the greater EL power efficiency is due not only to the higher optical transparency of the ITO film compared with Au film in a range of 300 to 900nm,but also to some new luminescence centers introduced in the Si oxide layer during the ITO deposition process.

关键词： film transparency layer

Gamma-Ray Irradiation Effects on Electroluminescence from Au/Extra Thin Si-Rich SiO_(2) Film/p-Si Structures

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Chinese Physics Letters 1998年第4期15卷 305-306页

作者： LI An-ping ZHANG Bo-rui QIAO Yong-ping qin guo-gang MA Zhen-chang ZONG Wan-hua Department of Physics Peking UniversityBeijing 100871 The 13th Institute of the Ministry of Electronic Industry Shijiazhuang 050051

We have studied the effects ofγ-ray irradiation on electroluminescence(EL)from Au/extra thin Si-rich SiO_(2) film/p-Si ***γ-ray irradiation,for the structure with a 600℃ annealed Si-rich SiO_(2) film a new blue EL band with a peak at around 480nm was observed,and for the structure with a 300℃ annealed Si-rich SiO_(2) film the red EL band shifts from 670 to 660nm and its intensity and full width at half maximum increase *** experimental results demonstrate that the defects induced byγ-ray irradiation are responsible for the blue EL band as well as for the variations of the red EL band.

关键词： annealed film Structures

THREE KINDS OF HYDROGEN-RELATED ELECTRON IRRADIATED DEFECTS IN SILICON GROWN IN HYDROGEN

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Chinese Physics Letters 1985年第1期2卷 43-47页

作者： HUA Zong-lu qin guo-gang ZHOU Jie Department of Physics Peking UniversityBeijing Institute of Semiconductors Academia SinicaBeijing

We have identified three kinds of hydrogen-related(HR)irradiated defects in Si crystals grown in H *** are located at 0.08eV and 0.20eV below the conduction band and 0.l0eV above the valance band *** they have different annealing temperatures,they are not the different charged states of the same defect center but correspond to different centers.

关键词： ADI annealing conduction

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大跨度粘土公路隧道台阶法施工技术探讨

华北水利水电学院学报 2009年第6期30卷 1-3页

作者：秦国刚中铁十三局集团公司第四工程有限公司黑龙江哈尔滨150008

在寒区大跨度浅埋粘土隧道施工中,因粘土含水量大、粘结力差、受施工扰动强度易衰减快,地基承载力低,施工方式选择不当易造成隧道坍塌.结合在建天恒山隧道大里程段台阶法施工的实践,对大跨度浅埋土质隧道采用台阶法施工中的开挖支护施... 详细信息

在寒区大跨度浅埋粘土隧道施工中,因粘土含水量大、粘结力差、受施工扰动强度易衰减快,地基承载力低,施工方式选择不当易造成隧道坍塌.结合在建天恒山隧道大里程段台阶法施工的实践,对大跨度浅埋土质隧道采用台阶法施工中的开挖支护施工工艺、施工质量控制要点等进行分析和探讨,指导了天恒山隧道的施工.天恒山浅埋粘土隧道三台阶法施工的成功应用为大跨度浅埋土质隧道的施工提供了技术资料,可供同类隧道施工借鉴.

关键词：隧道工程粘土隧道台阶法开挖支护控制要点

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厚大冲洪积层上水下抛石基床综合施工技术

杨凌职业技术学院学报 2009年第4期8卷 60-63页

作者：秦国刚中铁十三局集团第四工程有限公司黑龙江哈尔滨150008

大顶子山船闸上下游隔流堤、靠船墩均为抛石基床结构,抛石11万m3,其中水下6.7万m3。水下抛石高差难控制,抛石夯实质量不易保障,基床粗平和细平的平整度控制难度大。通过夯实试验,摸索出一整套基床整平的施工技术,解决了水下抛石基床施... 详细信息

大顶子山船闸上下游隔流堤、靠船墩均为抛石基床结构,抛石11万m3,其中水下6.7万m3。水下抛石高差难控制,抛石夯实质量不易保障,基床粗平和细平的平整度控制难度大。通过夯实试验,摸索出一整套基床整平的施工技术,解决了水下抛石基床施工质量控制等难题,并总结出一整套水下抛石基床施工技术并积累了经验。

关键词：抛石基床洪积层施工技术

Induced neural stem cells regulate microglial activation through Akt-mediated upregulation of CXCR4 and Crry in a mouse model of closed head injury

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Neural Regeneration Research 2025年第5期20卷 1416-1430页

作者： Mou Gao qin Dong Dan Zou Zhijun Yang Lili guo Ruxiang Xu Department of Neurosurgery Sichuan Academy of Medical Sciences and Sichuan Provincial People’s HospitalSchool of MedicineUniversity of Electronic Science and Technology of ChinaChengduSichuan ProvinceChina Department of Neurosurgery Chinese PLA General HospitalBeijingChina Department of Neurology Fu Xing HospitalCapital Medical UniversityBeijingChina

Microglial activation that occurs rapidly after closed head injury may play important and complex roles in neuroinflammation-associated neuronal damage and *** previously reported that induced neural stem cells can modulate the behavior of activated microglia via CXCL12/CXCR4 signaling,influencing their activation such that they can promote neurological ***,the mechanism of CXCR4 upregulation in induced neural stem cells remains *** this study,we found that nuclear factor-κB activation induced by closed head injury mouse serum in microglia promoted CXCL12 and tumor necrosis factor-αexpression but suppressed insulin-like growth factor-1 ***,recombinant complement receptor 2-conjugated Crry(CR2-Crry)reduced the effects of closed head injury mouse serum-induced nuclear factor-κB activation in microglia and the levels of activated microglia,CXCL12,and tumor necrosis factor-α.Additionally,we observed that,in response to stimulation(including stimulation by CXCL12 secreted by activated microglia),CXCR4 and Crry levels can be upregulated in induced neural stem cells via the interplay among CXCL12/CXCR4,Crry,and Akt signaling to modulate microglial *** agreement with these in vitro experimental results,we found that Akt activation enhanced the immunoregulatory effects of induced neural stem cell grafts on microglial activation,leading to the promotion of neurological recovery via insulin-like growth factor-1 secretion and the neuroprotective effects of induced neural stem cell grafts through CXCR4 and Crry upregulation in the injured cortices of closed head injury ***,these beneficial effects of Akt activation in induced neural stem cells were positively correlated with the therapeutic effects of induced neural stem cells on neuronal injury,cerebral edema,and neurological disorders post–closed head *** conclusion,our findings reveal that Akt activation may enhance the immunoregulatory effects of induced neura

关键词： Akt signaling cerebral edema closed head injury Crry CXCR4 induced neural stem cell microglia neuroinflammation

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隧道穿越顶部既有富水空区的综合施工技术

水利与建筑工程学报 2008年第1期6卷 30-33页

作者：秦国刚中铁十三局集团有限公司吉林长春130033

隧道穿越既有富水采空区综合施工技术是隧道建设中面临的特殊工程问题,目前我国采空区隧道建设技术尚处于摸索阶段。以在建重庆万(州)—开(县)高速公路铁峰山2号隧道为依托工程,对隧道穿越顶部富水采空区洞段,采用超前预注浆止水、周边... 详细信息

隧道穿越既有富水采空区综合施工技术是隧道建设中面临的特殊工程问题,目前我国采空区隧道建设技术尚处于摸索阶段。以在建重庆万(州)—开(县)高速公路铁峰山2号隧道为依托工程,对隧道穿越顶部富水采空区洞段,采用超前预注浆止水、周边径向注浆堵水等治水方法,堵排结合,有效地控制了隧道施工中涌水等现象,保证了隧道施工安全顺利进行。该隧道的施工经验可为同类工程的施工提供有益的借鉴和参考。

关键词：隧道工程既有空区富水施工技术