keyword
MENU ▼
Read by QxMD icon Read
search

germanium

keyword
https://www.readbyqxmd.com/read/29916516/formation-of-nanocrystalline-graphene-on-germanium
#1
Rana Yekani, Evgenia Rusak, Adnan Riaz, Alexandre Felten, Ben Breitung, Simone Dehm, Delwin Perera, Jochen Rohrer, Carsten Rockstuhl, Ralph Krupke
Graphitization of a polymer layer provides a convenient route to synthesize nanocrystalline graphene on dielectric surfaces. The transparent and conducting wafer scale material is of interest as a membrane and a coating, and for the generation and detection of light, or strain sensing. In this work, we study the formation of nanocrystalline graphene on germanium, a surface which promotes the CVD synthesis of monocrystalline graphene. The surprising result that we obtained through graphitization is the formation of cavities in germanium, over which nanocrystalline graphene is suspended...
June 19, 2018: Nanoscale
https://www.readbyqxmd.com/read/29907053/vibrational-spectroscopic-study-of-ph-dependent-solvation-at-a-ge-100-water-interface-during-an-electrode-potential-triggered-surface-termination-transition
#2
Fang Niu, Martin Rabe, Simantini Nayak, Andreas Erbe
The charge-dependent structure of interfacial water at the n-Ge(100)-aqueous perchlorate interface was studied by controlling the electrode potential. Specifically, a joint attenuated total reflection infrared spectroscopy and electrochemical experiment was used in 0.1M NaClO4 at pH ≈ 1-10. The germanium surface transformation to an H-terminated surface followed the thermodynamic Nernstian pH dependence and was observed throughout the entire pH range. A singular value decomposition-based spectra deconvolution technique coupled to a sigmoidal transition model for the potential dependence of the main components in the spectra shows the surface transformation to be a two-stage process...
June 14, 2018: Journal of Chemical Physics
https://www.readbyqxmd.com/read/29905715/mid-infrared-high-q-germanium-microring-resonator
#3
Ting-Hui Xiao, Ziqiang Zhao, Wen Zhou, Chin-Yao Chang, Sze Yun Set, Mitsuru Takenaka, Hon Ki Tsang, Zhenzhou Cheng, Keisuke Goda
Germanium is a promising material for mid-infrared (MIR) integrated photonics due to its CMOS compatibility and wide transparency window covering the fingerprint spectral region (2-15 μm). However, due to the limited quality and structural configurations of conventional germanium-based integration platforms, the realization of high-Q on-chip germanium resonators in the MIR spectral range remains challenging to date. Here we experimentally demonstrate an air-cladding MIR germanium microring resonator with, to the best of our knowledge, the highest loaded Q-factor of ∼57,000 across all germanium-based integration platforms to date...
June 15, 2018: Optics Letters
https://www.readbyqxmd.com/read/29905690/influence-of-attenuation-on-self-organized-second-harmonic-generation-in-a-germanium-doped-microstructured-silica-fiber
#4
Syliwa Majchrowska, Jakub Pabisiak, Tadeusz Martynkien, Paweł Mergo, Karol Tarnowski
Observation of the efficient second-harmonic generation (SHG) in silica fibers drew a lot of interest, as second-order processes in centrosymmetric materials should not occur. In this Letter, we extended a theoretical model of self-organized SHG to include an attenuation and investigated the influence of fiber loss on the self-organized SHG process. We performed calculations of energy conversion efficiency for SHG in microstructured optical fibers. Finally, we referred the simulation results to the measured SHG efficiency in a microstructured side-hole germanium-doped silica fiber...
June 15, 2018: Optics Letters
https://www.readbyqxmd.com/read/29897093/tin-and-germanium-based-two-dimensional-ruddlesden-popper-hybrid-perovskites-for-potential-lead-free-photovoltaic-and-photoelectronic-applications
#5
Liang Ma, Ming-Gang Ju, Jun Dai, Xiao Cheng Zeng
Despite their high power conversion efficiency, the commercial applications of hybrid organic-inorganic lead (Pb) halide perovskite based solar cells are still hampered by concerns about the toxicity of Pb and the structural stability in open air. Herein, based on density-functional theory computation, we show that lead-free tin (Sn) and germanium (Ge) based two-dimensional (2D) Ruddlesden-Popper hybrid organic-inorganic perovskites with a thickness of a few unit-cells, BA2MAn-1MnI3n+1 (M = Sn or Ge, n = 2-4), possess desirable electronic, excitonic and light absorption properties, thereby showing promise for photovoltaic and/or photoelectronic applications...
June 13, 2018: Nanoscale
https://www.readbyqxmd.com/read/29896377/triple-bonds-of-niobium-with-silicon-germaniun-and-tin-the-tetrylidyne-complexes-%C3%AE%C2%BA-3-tmps-co-2-nb-0000000000000000000000000000000000-0000000000000000000000000000000000-0000000000000000000000000000000000-0000000000000000000000000000000000-0000000000000000000000000000000000
#6
Alexander C Filippou, David Hoffmann, Gregor Schnakenburg
A systematic, efficient approach to first complexes containing a triple bond between niobium and the elements silicon, germanium or tin is reported. The approach involves a metathetical exchange of the niobium-centered nucleophile (NMe4 )[Nb(CO)4 (κ2 -tmps)] ( 1 ) (tmps = MeSi(CH2 PMe2 )3 ) with a suitable organotetrel(ii)halide. Compound 1 was obtained from (NMe4 )[Nb(CO)6 ] and the triphosphane tmps by photodecarbonylation. Reaction of 1 with the disilene E -Tbb(Br)Si 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 1111111111111111111111111111111111 1111111111111111111111111111111111 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 1111111111111111111111111111111111 1111111111111111111111111111111111 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 Si(Br)Tbb in the presence of 4-dimethylaminopyridine afforded selectively the red-brown silylidyne complex [(κ3 -tmps)(CO)2 Nb 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 1111111111111111111111111111111111 1111111111111111111111111111111111 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 1111111111111111111111111111111111 1111111111111111111111111111111111 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 1111111111111111111111111111111111 1111111111111111111111111111111111 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 Si-Tbb] ( 2-Si , Tbb = 4- tert -butyl-2,6-bis(bis(trimethylsilyl)methyl)phenyl)...
September 1, 2017: Chemical Science
https://www.readbyqxmd.com/read/29883176/first-limit-on-the-direct-detection-of-lightly-ionizing-particles-for-electric-charge-as-low-as-e-1000-with-the-majorana-demonstrator
#7
S I Alvis, I J Arnquist, F T Avignone, A S Barabash, C J Barton, F E Bertrand, V Brudanin, M Busch, M Buuck, T S Caldwell, Y-D Chan, C D Christofferson, P-H Chu, C Cuesta, J A Detwiler, C Dunagan, Yu Efremenko, H Ejiri, S R Elliott, T Gilliss, G K Giovanetti, M P Green, J Gruszko, I S Guinn, V E Guiseppe, C R Haufe, L Hehn, R Henning, E W Hoppe, M A Howe, S I Konovalov, R T Kouzes, A M Lopez, R D Martin, R Massarczyk, S J Meijer, S Mertens, J Myslik, C O'Shaughnessy, G Othman, W Pettus, A W P Poon, D C Radford, J Rager, A L Reine, K Rielage, R G H Robertson, N W Ruof, B Shanks, M Shirchenko, A M Suriano, D Tedeschi, R L Varner, S Vasilyev, K Vorren, B R White, J F Wilkerson, C Wiseman, W Xu, E Yakushev, C-H Yu, V Yumatov, I Zhitnikov, B X Zhu
The Majorana Demonstrator is an ultralow-background experiment searching for neutrinoless double-beta decay in ^{76}Ge. The heavily shielded array of germanium detectors, placed nearly a mile underground at the Sanford Underground Research Facility in Lead, South Dakota, also allows searches for new exotic physics. Free, relativistic, lightly ionizing particles with an electrical charge less than e are forbidden by the standard model but predicted by some of its extensions. If such particles exist, they might be detected in the Majorana Demonstrator by searching for multiple-detector events with individual-detector energy depositions down to 1 keV...
May 25, 2018: Physical Review Letters
https://www.readbyqxmd.com/read/29883126/germanium-sulfide-nano-optics-probed-by-stem-cathodoluminescence-spectroscopy
#8
Peter Sutter, Christos Argyropoulos, Eli Sutter
Nano-optical studies of confined modes in planar waveguides have attracted significant interest as a means to probe exciton-polaritons and other hybrid light-matter quasiparticles in layered semiconductors, such as transition metal dichalcogenides or boron nitride. There is a need to broaden such studies to other materials and to identify alternatives to scanning near-field optical microscopy for exciting and measuring confined waveguide modes. Here, we establish an approach for probing the dispersion of traveling waveguide modes by cathodoluminescence spectroscopy excited by the focused electron beam in scanning transmission electron microscopy (STEM-CL), and apply it to solid-state resonators consisting of mesoscale monocrystalline prisms and plates composed of GeS, an anisotropic layered semiconductor with direct bandgap in the near-infrared spectral range...
June 8, 2018: Nano Letters
https://www.readbyqxmd.com/read/29879531/standardization-of-64-cu-activity
#9
D E Bergeron, J T Cessna, R Fitzgerald, L Pibida, B E Zimmerman
The complex decay scheme that makes 64 Cu promising as both an imaging and therapeutic agent in medicine also makes the absolute measurement of its activity challenging. The National Institute of Standards and Technology (NIST) has completed a primary activity standardization of a 64 CuCl2 solution using the 4πβ(LS)-γ(NaI) live-timed anticoincidence (LTAC) counting method with a combined standard uncertainty of 0.51 %. Two liquid scintillation (LS) counting methods were employed for confirmatory measurements...
May 25, 2018: Applied Radiation and Isotopes
https://www.readbyqxmd.com/read/29867070/theoretical-study-of-the-photolysis-mechanisms-of-methylpentaphenyldimetallanes-ph%C3%A2-mm-ph%C3%A2-me-m-m-si-and-ge
#10
Shih-Hao Su, Ming-Der Su
The mechanisms of the photolysis reactions are studied theoretically at the M06-2X/6-311G(d) level of theory, using the four types of group 14 molecules that have the general structure, Ph₃M⁻M'Ph₂Me (M and M' = Si and Ge), as model systems. This study provides the first theoretical evidence for the mechanisms of these photorearrangements of compounds that contain a M⁻M' single bond. The model investigations indicate that the preferred reaction route for the photolysis reactions is, as follows: reactant → Franck-Condon (FC) region → minimum (triplet) → transition state (triplet) → triplet/singlet intersystem crossing → photoproducts (both di-radicals and singlets)...
June 4, 2018: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/29801271/formation-of-laser-active-centers-in-bismuth-doped-high-germania-silica-fibers-by-thermal-treatment
#11
Sergei Firstov, Alexander Kharakhordin, Sergey Alyshev, Konstantin Riumkin, Elena Firstova, Mikhail Melkumov, Vladimir Khopin, Alexey Guryanov, Evgeny Dianov
The effect of thermal annealing on the luminescent and laser properties of high-germania-core silicate fibers doped with bismuth was investigated. We studied the behavior of optical absorption assigned to the bismuth-related active centers associated with germanium as well as the behavior of unsaturable absorption in annealed fibers with respect to the Bi content. The dependence of the increment of the active center content on the Bi concentration in the annealed fibers was obtained. We achieved laser oscillations near a wavelength of 1700 nm with a slope efficiency of 18% using a 8...
May 14, 2018: Optics Express
https://www.readbyqxmd.com/read/29787431/rapid-response-dose-assessment-and-clinical-management-of-a-plutonium-contaminated-puncture-wound
#12
Stephen L Sugarman, William M Findley, Richard E Toohey, Nicholas Dainiak
Internalization of radionuclides occurs not only by inhalation, ingestion, parenteral injection (i.e., administration of radioactive material for a medical purpose), and direct transdermal absorption, but also by contaminated wounds. In June 2010, a glove-box operator at the U.S. Department of Energy's Savannah River Site sustained a puncture wound while venting canisters containing legacy materials contaminated with Pu. To indicate the canisters had been vented, a flag was inserted into the vent hole. The shaft of the flag penetrated the protective gloves worn by the operator...
July 2018: Health Physics
https://www.readbyqxmd.com/read/29786970/density-functional-theory-calculations-revealing-metal-like-band-structures-for-ultrathin-ge-111-and-211-surface-layers
#13
Chih-Shan Tan, Michael Hsuan-Yi Huang
To find out if germanium should also possess facet-dependent electrical conductivity properties, surface state density functional theory (DFT) calculations were performed on 1-6 layers of Ge (100), (110), (111), and (211) planes. Tunable Ge (100) and (110) planes always present the same semiconducting band structure with a band gap of 0.67 eV expected of bulk germanium. In contrast, 1, 2, 4, and 5 layers of Ge (111) and (211) plane models show metal-like band structures with continuous density of states (DOS) throughout the entire band...
May 21, 2018: Chemistry, An Asian Journal
https://www.readbyqxmd.com/read/29782155/a-narrow-gap-semiconducting-germanium-allotrope-from-the-oxidation-of-a-layered-zintl-phase-in-ionic-liquids
#14
Zhongjia Tang, Alexander P Litvinchuk, Melissa Gooch, Arnold M Guloy
A metastable germanium allotrope, Ge(oP32), was synthe-sized as polycrystalline powders and single crystals from the mild-oxidation/delithiation of Li7Ge12 in ionic liquids. Its crystal structure, from single crystal X-ray diffraction (P bcm, a = 8.1527(4) Å, b = 11.7572(5) Å, c = 7.7617(4) Å), features a complex covalent network of 4-bonded Ge, resulting from a well-ordered topotactic oxidative condensation of [Ge12 ]7- layers. It is a diamagnetic semiconductor (Eg = 0.33 eV), and transforms exothermically and irreversibly to α-Ge at 363 °C...
May 21, 2018: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/29781443/ion-beam-induced-bending-of-semiconductor-nanowires
#15
Imran Hanif, Osmane Camara, Matheus Araújo Tunes, Robert William Harrison, Graeme Greaves, Stephen E Donnelly, Jonathan A Hinks
The miniaturization of technology increasingly requires the development of both new structures as well as novel techniques for their manufacture and modification. Semiconductor nanowires (NWs) are a prime example of this and as such have been the subject of intense scientific research for applications ranging from microelectronics to nano-electromechanical devices. Ion irradiation has long been a key processing step for semiconductors and the natural extension of this technique to the modification of semiconductor NWs has led to the discovery of ion-beam-induced deformation effects...
May 21, 2018: Nanotechnology
https://www.readbyqxmd.com/read/29774896/low-temperature-solution-synthesis-of-silicon-germanium-and-si-ge-axial-heterostructures-in-nanorod-and-nanowire-form
#16
G Flynn, K Stokes, K M Ryan
Herein, we report the formation of silicon, germanium and more complex Si-SixGe1-x and Si-Ge axial 1D heterostructures, at low temperatures in solution. These nanorods/nanowires are grown using phenylated compounds of silicon and germanium as reagents, with precursor decomposition achieved at substantially reduced temperatures (200 °C for single crystal nanostructures and 300 °C for heterostructures), through the addition of a reducing agent. This low energy route for the production of these functional nanostructures as a wet chemical in high yield is attractive to meet the processing needs for next generation photovoltaics, batteries and electronics...
May 18, 2018: Chemical Communications: Chem Comm
https://www.readbyqxmd.com/read/29770414/mesoporous-germanium-nanoparticles-synthesized-in-molten-zinc-chloride-at-low-temperature-as-a-high-performance-anode-for-lithium-ion-batteries
#17
Xianyu Liu, Ning Lin, Wenlong Cai, Yingyue Zhao, Jianbin Zhou, Jianwen Liang, Yongchun Zhu, Yitai Qian
In a simple and convenient way, mesoporous germanium nanoparticles (mp-Ge NPs) are prepared by a "metathesis" reaction of magnesium germanide (Mg2Ge) and zinc chloride (ZnCl2) in an autoclave at 300 °C. Investigated as anode materials for lithium-ion batteries, the prepared mp-Ge NPs exhibit a high capacity retention of 1048 mA h g-1 at 1 C after 1000 cycles and a high rate capacity of 727.1 mA h g-1 at 10 C in Li-Ge half cells. Additionally, a 3.4 V lithium-ion full cell (Ge-LiCoO2) with an energy retention of 85% (∼268...
May 17, 2018: Dalton Transactions: An International Journal of Inorganic Chemistry
https://www.readbyqxmd.com/read/29765802/computational-exploration-of-two-dimensional-silicon-diarsenide-and-germanium-arsenide-for-photovoltaic-applications
#18
Sri Kasi Matta, Chunmei Zhang, Yalong Jiao, Anthony O'Mullane, Aijun Du
The properties of bulk compounds required to be suitable for photovoltaic applications, such as excellent visible light absorption, favorable exciton formation, and charge separation are equally essential for two-dimensional (2D) materials. Here, we systematically study 2D group IV-V compounds such as SiAs2 and GeAs2 with regard to their structural, electronic and optical properties using density functional theory (DFT), hybrid functional and Bethe-Salpeter equation (BSE) approaches. We find that the exfoliation of single-layer SiAs2 and GeAs2 is highly feasible and in principle could be carried out experimentally by mechanical cleavage due to the dynamic stability of the compounds, which is inferred by analyzing their vibrational normal mode...
2018: Beilstein Journal of Nanotechnology
https://www.readbyqxmd.com/read/29757620/separation-of-protactinium-employing-sulfur-based-extraction-chromatographic-resins
#19
Tara Mastren, Benjamin W Stein, T Gannon Parker, Valery Radchenko, Roy Copping, Allison Owens, Lance E Wyant, Mark Brugh, Stosh A Kozimor, F Meiring Nortier, Eva R Birnbaum, Kevin D John, Michael Ernst-Heinrich Fassbender
Protactinium-230 (t1/2 17.4 d) is the parent isotope of 230U (t1/2 20.8 d), a radionuclide of interest for targeted alpha therapy (TAT). Column chromatographic methods have been developed to separate no-carrier-added 230Pa from proton irradiated thorium targets and accompanying fission products. Results reported within demonstrate the use of novel sulfur bearing chromatographic extraction resins for the selective separation of protactinium. The recovery yield of 230Pa was 93 ± 4 % employing a R3P=S type commercially available resin and 88 ± 4 % employing a DGTA (diglycothioamide) containing custom synthesized extraction chromatographic resin...
May 14, 2018: Analytical Chemistry
https://www.readbyqxmd.com/read/29747084/investigation-of-the-aluminum-oxide-content-on-structural-and-optical-properties-of-germanium-glasses-doped-with-re-ions
#20
R Jadach, J Zmojda, M Kochanowicz, P Miluski, J Pisarska, W A Pisarski, M Sołtys, M Lesniak, M Sitarz, D Dorosz
In this paper structural and optical properties of Rare Earth doped (RE) gallo-germanate glasses modified with various amount of Al2 O3 have been investigated. Glasses doped with Yb3+ , Tm3+, and Ho3+ ions were synthesized to study Al2 O3 additive influence on their structural and emission properties in the visible spectral region. MIR spectra indicated that the structure of prepared glasses tends to order and its polymerization along with the aluminum content increase. Glass samples consisting of the low molar content of Al2 O3 are characterized by a significant contribution of Tm3+ ions in light emission while Ho3+ ions luminescence dominates in samples consisting of the higher molar content of Al2 O3 ...
April 23, 2018: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
keyword
keyword
38018
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"