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AC Conductivity of (As_2Te_3)_(100-x)ge_x Bulk Glassy System

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Journal of Materials Science & Technology 1998年第3期14卷 247-250页

作者： A-Abdel-All(Physics Dept., Faculty of Science, Helwan University, Cairo, Egypt) Physics Dept. Faculty of Science Helwan University Cairo Egypt

The ac conductivity of the bulk amorphous chalcogenide system (As2Te3)100-xgex (where x=0,5,10,15 and 25 at. pct) was investigated at variable frequencies ranging from 50 Hz to 100 kHz and at different temperatures ranging from 3O to 160℃. lt was found that at a fixed temperature, where n ges. All samples give a semicircle arc originating at the origin point. This indicates that each composition can be described only by one resistance R and one capacity C, both parallelly combined. The centre below the real axis indicates the relaxation behaviour of the system. The activation energies for conduction were calculated.

关键词： ge Te AC Conductivity of x)ge_x Bulk Glassy System As2Te3

Variation of Electronic Structure with C Content in Si_(1-x-y)ge_xC_y/Si(001) System

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Journal of Materials Science & Technology 1999年第4期15卷 296-298页

作者： Meichun HUANG Liqing WU and Zizhong ZHU(Department of Physics, Xiamen University, Xiamen 361005, China)To whom correspondence should be addressedE-mail: wlq@yanan. xmu. edu. cn Department of Physics Xiamen University Xiamen 361005 China

The electronic structures of strained Si 1-x-.ge. C. (y<0.09) alloys on Si(001) have been studiedby the ab initio pseudopotential method within the local density functionaI theory. The variationsof the minim um band g... 详细信息

The electronic structures of strained Si 1-x-.ge. C. (ygether with the average bond energy theory. It is found that thedependences of the minimum band gap and the valence-band offset on the alloy compositionchange around the point of zero lattice mismatch. A comparison between our theoreticaf results and the available experimental data indicates that some of the contradictions from differentresearch groups can be reasonably explained.

关键词： ge x-y)ge_xC_y/Si System

A Novel Sample Introduction Technique for the Simultaneous Determination of As,Se,ge and Hg in Chinese Medicinal Material

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Chemical Research in Chinese Universities 2001年第4期17卷 400-406页

作者： Chen Bin Zhuang Zhixia Wang Xiaoru FRANKs.c.lee 厦门大学教育部现代分析科学重点实验室福建厦门 361005 香港浸会大学香港

A novel technique of Moveable Reduction Bed Hydride generator（MRBHG）was applied tohe hydride generation or cold vapor generation of As，Se，ge，and Hg existing In TraditionalChinese Medicinal Material（TCM）．The simultaneous determination of the multi－elements wasperformed with ICP－MS．A solid reduction system involving the use of potassiumtetraborohydride and tartaric acid was applied to generating metal hydride or cold *** factors affecting the metal cold vapor generation were *** mainadvantage of the technique is that only a 4μL volume of sample was required for the cold vapor

关键词： for the Simultaneous Determination of As,Se,ge A Novel Sample Introduction Technique Chinese Material Medicinal and Hg ge

ge surface passivation by geO2 fabricated by N2O plasma oxidation

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Science China(Information Sciences) 2015年第4期58卷 143-147页

作者： LIN Meng AN Xia LI Ming YUN QuanXin LI Min LI Zhi Qiang LIU PengQiang ZHANG Xing HUANG Ru Key Laboratory of Microelectronic Devices and Circuits Institute of MicroelectronicsPeking University

In this paper, ge surface passivation by ge O2 grown by N2 O plasma oxidation is presented and experimentally demonstrated. Results show that stoichiometrically ge O2 can be achieved by N2 O plasma oxidation at 350°C. The transmission electron microscope observation reveals that the ge O2/ge interface is automatically smooth and the thickness of ge O2is～0.9 nm with 120 s N2 O plasma oxidation. The interface state density of ge surface after N2 O plasma passivation is about～3×1011 cm-2e V-1. With ge O2 passivation,the hysteresis of MOS capacitor with Al2O3 as gate dielectric is reduced to～55 m V, compared to 130 m V of the untreated one. The Fermi-level at ge O2/ge interface is unpinned, and the surface potential is effectively modulated by the gate voltage, which is promising for high performance NMOSFETs fabrication.

关键词： ge passivation ge O 2 N 2 O plasma oxidation

Room-temperature direct-bandgap photoluminescence from strain-compensated ge/Sige multiple quantum wells on silicon

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Chinese Physics B 2012年第1期21卷 493-498页

作者： Hu Wei-Xuan Cheng Bu-Wen Xue Chun-Lai Zhang Guang-Ze Su Shao-Jian Zuo Yu-Hua Wang Qi-Ming State Key Laboratory on Integrated Optoelectronics Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China

Strain-compensated ge/Si0.15ge0.85 multiple quantum wells were grown on an Si0.1 ge0.9 virtual substrate using ultrahigh vacuum chemical vapor deposition technology on an n＋-Si（001） substrate. Photoluminescence measurements were performed at room temperature, and the quantum confinement effect of the direct-bandgap transitions of a ge quantum well was observed, which is in good agreement with the calculated results. The luminescence mechanism was discussed by recombination rate analysis and the temperature dependence of the luminescence spectrum.

关键词： ge multiple quantum wells strain compensated

Structural transformation of ge dimers on ge(001) surfaces induced by bias voltage

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Chinese Physics B 2008年第12期17卷 4580-4584页

作者：秦志辉时东霞高鸿钧 Nanoscale Physics & devices Laboratory Institute of Physics Chinese Academy of Sciences

Scanning tunnelling microscopy is utilized to investigate the local bias voltage tunnelling dependent transformation between （2×1） and c（4×2） structures on ge（001） surfaces, which is reversibly observed at room temperature and a critical bias voltage of -0.80 V. Similar transformation is also found on an epitaxial Ce islands but at a slightly different critical bias voltage of -1.00V. It is found that the interaction between the topmost atoms on the STM tip and the atoms of the dimers, and the pinning effect induced by Sb atoms, the nacancies or the epitaxial clusters, can drive the structural transformation at the critical bias voltage.

关键词： scanning tunnelling microscopy surface structures ge structural transition

Cementitious property of NaAlO2-activated ge slag as cement supplement

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International Journal of Minerals,Metallurgy and Materials 2019年第12期26卷 1594-1603页

作者： Hua-zhe Jiao Shu-fei Wang Ai-xiang Wu Hui-ming Shen Jian-dong Wang International Joint Research Laboratory of Henan Province for Underground Space Development and Disaster Prevention Henan Polytechnic UniversityJiaozuo 454000China School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China

germanium(ge),a waste residue leaching from zinc(Zn)smelting process,has potential cementitious properties and could be recycled as a cement supplement activated by chemical *** this work,a test was conducted to determine the hydration properties of ge slag-cement-based composites with ge slag(GS)/ordinary Portland cement(PC)contents of 0wt%,5wt%,10wt%,15wt%,20wt%,and 25wt% and water-to-binder ratio(w/b)of *** activators Ca(OH)2,AlCl3,NaAlO2,and Na2CO3 were mixed under 1wt%,2wt%,3wt%,and 4wt% dosages of GS *** composition and microstructure of the hydration products were investigated by the combined approaches of X-ray diffraction(XRD),thermogravimetry-differential scanning calorimetry(TG-DSC),scanning electron microscopy(SEM),and energy-dispersive X-ray spectroscopy(EDS).First,the GS cementitious property is attributed to the high content of CaSO4·***,the activators affected the acceleration performance in the following order:NaAlO2,Na2CO3,AlCl3,and Ca(OH)*** importantly,the 28-day unconfined compressive strength(UCS)is 45.34 MPa at the optimum formula of 0.6wt% NaAlO2,15wt% GS,and 85wt% PC,which is 9.16% higher than the ***,NaAlO2 is beneficial for the ettringite(AFt)generation,resulting in the C-S-H structure ***,the Zn^2+ residue inhibited the AFt formation,representing an important challenge to the strength growth with curing ***,the GS could be recycled as a supplement to the cement under the activator NaAlO2.

关键词： ge slag from zinc process recycling activator cement supplements strength

Pressure-induced phase transitions in the ZrXY(X=Si,ge,Sn;Y=S,Se,Te)family compounds

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Chinese Physics B 2022年第5期31卷 553-560页

作者： Qun Chen Juefei Wu Tong Chen Xiaomeng Wang Chi Ding Tianheng Huang Qing Lu Jian Sun National Laboratory of Solid State Microstructures School of Physics and Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China Laboratory of Computational Physics Institute of Applied Physics and Computational MathematicsBeijing 100230China

Pressure is an effective and clean way to modify the electronic structures of materials,cause structural phase transitions and even induce the emergence of ***,we predicted several new phases of the Zr XY family at high pressures using the crystal structures search method together with first-principle *** particular,the Zr ge S compound undergoes an isosymmetric phase transition from P4/nmm-I to P4/nmm-II at approximately 82 *** band structures show that all the high-pressure phases are *** these new structures,P4/nmm-II Zr ge S and P4/mmm Zr ge Se can be quenched to ambient pressure with superconducting critical temperatures of approximately 8.1 K and 8.0 K,*** study provides a way to tune the structure,electronic properties,and superconducting behavior of topological materials through pressure.

关键词： high pressure ZrXY(X=Si ge Sn Y=S Se Te)family phase transition superconducting temperature

Meso-porous amorphous ge:Synthesis and mechanism of an anode material for Na and K storage

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Nano Research 2019年第8期12卷 1824-1830页

作者： Zheng Yi Ning Lin Tieqiang Li Ying Han Yang Li Yitai Qian Department of Applied Chemistry University of Science and Technology of ChinaHefei 230026China

Crystalline ge is a highly active anode material for Li storage but inactive for Na storage because of high diffusion barrier. By in-situ Raman spectrum, we explore that the Na could reversibly ailoy/dealloy with the amorphous ge, but does not with the crystalline ge. Herein, the amorphous ge is fabricated by an acid-etching Zintl phase Mg2ge route at room temperature, which shows a mesoporous architecture with a Brunauer-Emmett-Teller (BET) surface area of 29.9 m^2·g^-1 and a Barrett-Joyner-Halenda (BJH) average pore diameter of 7.6 nm. This mesoporous architecture would enhance the Na-ion/electron diffusion rate and buffer the volume expansion. As a result, the as-prepared amorphous ge shows superior Na-ion storage performance including high reversible capacity over 550 mA·h·g^-1 at 0.2 C after 50 cycles, good rate capability with a capacity of 273 mA·h·g^-1 maintained at 5.0 C, and long-term cycling stability with capacities of 450 mA·h·g^-1 at 0.4 C after 200 cycles. For the K-ion storage, the amorphous ge is also more active than the crystalline counter and maintains a capacity of 210 mA·h·g^-1 after 100 cycles at 0.2 C.

关键词： amorphous ge sodium-ion batteries K storage in-situ Raman spectrum