Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Electronic Resource  (117)
  • 2000-2004  (53)
  • 1990-1994  (63)
  • 1965-1969  (1)
  • 1
    Electronic Resource
    Electronic Resource
    Diffusion of both Ga and Bi into InSb seeds during growth of InGaSbBi (1994)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 76 (1994), S. 858-864 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: In1−xGaxSb1−yBiy (0〈x≤0.21, 0〈y≤0.005) quaternary bulk single crystals were grown on InSb seed crystals using a rotary Bridgman method. In order to investigate the quality of these crystals, various kinds of measurements were carried out, such as optical microscope, x-ray topograph, four-crystal x-ray diffractometry, electron-probe microanalysis, energy-dispersive spectroscopy, and secondary-ion-mass spectroscopy. All grown crystals were 10 mm in diameter and more than 10 mm in length. This indicates that the rotary Bridgman method was useful to grow quaternary bulk single crystals. Owing to segregation, the compositional ratio of Bi (y) increased and that of Ga (x) decreased as crystals grew. During growth of InGaSbBi, both Ga and Bi diffused into the InSb seed and there appeared domains of InBi. For comparison, InSb1−yBiy (0〈y≤0.05) and In1−xGaxSb (0〈x≤0.16) were grown on InSb. It turned out that Bi did not diffuse into InSb without Ga, but Ga diffused without Bi. The incorporation of Ga produced the excess In and as a result InBi domains were formed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.357761
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Effects of mechanical stress on the volume phase transition of poly(N-isopropylacrylamide) based polymer gels (2000)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 113 (2000), S. 7640-7645 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The effects of mechanical stress on the volume phase transition of a poly(N-isopropylacrylamide) (PNIPA) gel as well as a copolymer gel composed of N-isopropylacrylamide (NIPA) and sodium acrylate (SA) were investigated in the relatively low stress region. The PNIPA gel without elongational stress showed the behavior close to the second order phase transition. The character of the first order transition became clear under tension, and the transition temperature increased with increasing applied stress. Similar behavior was observed for the NIPA-SA copolymer gel, but the copolymer gel showed the first order transition in the whole stress range investigated. The thermodynamical linear region, where the transition temperature varies linearly with applied stress, was narrower than the mechanical linear region determined by the stress–strain relation of the gels. The change in the transition behavior by the application of the mechanical stress originated chiefly from the volume change in the gels by the applied mechanical stress. It was found that the curve of the transition temperature against applied stress corresponds to the phase boundary between the swollen and collapsed phases for the gels. On the basis of the experimental data, a phenomenological model describing the volume phase transition of the polymer gels is proposed in the frame of the Landau-type free energy expression. © 2000 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1312273
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Platelet superoxide dismutase in migraine and tension-type headache (1994)
    USA/Oxford, UK : American Association for the Study of Headache/Blackwell Science Ltd
    Cephalalgia 14 (1994), S. 0 
    Details
    ISSN: 1468-2982
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Superoxide dismutase (SOD) is a radical-scavenging enzyme. We determined Cu, Zn-SOD concentrations and activities in platelets from subjects with migraine and tension-type headaches. Thirty migraine without aura (MWoA) patients, 9 migraine with aura (MWA) patients, and 53 tension-type headache patients were selected for study. Thirty healthy volunteers composed the control group. Concentrations of platelet SOD were determined using enzyme-linked immunosorbent assay techniques. The activity of platelet SOD was determined by measuring reductivity of nitroblue tetrazolium. Low concentrations of platelet SOD were found in patients with MWA and MWoA. Platelet SOD activity decreased in MWA patients but not in patients with MWoA or tension-type headaches. These findings suggest vulnerability to oxidative stress in patients with migraine. It is suggested that low platelet SOD levels may play an important role in the etiology of migraine.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1468-2982.1994.014003215.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Impact improvement mechanism of HIPS with bimodal distribution of rubber particle size (1991)
    s.l. : American Chemical Society
    Macromolecules 24 (1991), S. 5639-5644 
    Details
    ISSN: 1520-5835
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/ma00020a024
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Magnetotransport properties of MnAs/GaAs/MnAs ferromagnet/semiconductor trilayer heterostructures (2000)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 87 (2000), S. 6695-6697 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We have succeeded in growing MnAs/GaAs/MnAs ferromagnet/semiconductor trilayer heterostructures on GaAs(111)B substrates by molecular-beam epitaxy. Double-step features were observed in magnetization characteristics due to the difference in coercive force between the top and bottom MnAs layers. Magnetoresistance (MR) curves in current-in-plane geometry showed the spin-valve effect, which was caused by the change of the magnetic alignment of the two ferromagnetic MnAs layers from parallel to antiparallel orientation. Temperature dependence of the MR was also investigated. We infer that the positive temperature coefficient of the MR by the spin-valve effect suggests the heat (carrier) induced interlayer exchange coupling. © 2000 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.372811
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Disktron accelerator (1993)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 64 (1993), S. 2466-2474 
    Details
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: A new type of low-energy ion accelerator has been developed. It includes an eight-storied Disktron generator, newly developed accelerating tubes which hold up to 4 MV/m, both single and tandem acceleration capability, and a compound negative ion source. The Disktron generates 3.2 MV with a dummy load and 2.2 MV with ion beams, and has a voltage stability better than 10−3 at around 1 MV with a corona feedback stabilizer or a generating voltmeter feedback stabilizer only. The highly stabilized voltage of the Disktron has particularly been allowed to form an ion microbeam of about 1-μm diameter.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1143905
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Chemical vapor deposition diamond window as vacuum and tritium confinement barrier for fusion application (2000)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 71 (2000), S. 4139-4143 
    Details
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: A pressure resistant polycrystalline chemical vapor deposition (CVD) diamond disk for a microwave window is used for a vacuum and a tritium confinement boundary in fusion applications. A pressure test of a CVD diamond window disk (2.25 mm in thickness and 100 mm in diameter) was carried out. It was demonstrated that the diamond window tolerated 1.0 MPa (10 atm) in the plenum. The displacement of the window center for both the growth and the nucleation side on the unpressurized side is 40±1 and 41±1 μm, respectively, at the pressure of 1.0 MPa, and these values agree well with those calculated. No damage in the disk and the braze, and no vacuum leakage in the assembly was observed. This result demonstrates that the diamond window assembly could tolerate up to 1.45 MPa. It was experimentally proved that the diamond window satisfied the safety requirement of 0.5 MPa resistance for the vacuum and the tritium confinement boundary of an International Thermonuclear Experimental Reactor. The design prospect for the diamond window of the electron cyclotron heating and current drive system is also discussed, based on the stress analysis using the ABAQUS code. © 2000 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1313799
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Growth of aligned carbon nanotubes by plasma-enhanced chemical vapor deposition: Optimization of growth parameters (2001)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 90 (2001), S. 1529-1533 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Direct-current plasma-enhanced chemical vapor deposition (CVD) with mixtures of acetylene and ammonia was optimized to synthesize aligned carbon nanotubes (CNTs) on Co- or Ni-covered W wires with regard to wire temperature, wire diameter, gas pressure, and sample bias. A phase diagram of CNT growth was established experimentally in this optimization process. It was revealed by transmission electron microscopy that Co-catalyzed CNTs encapsulated a Co carbide nanoparticle at their tip, disagreeing with a previous report that Co particles were located at the base of CNTs CVD grown on Co-covered Si substrates [C. Bower et al., Appl. Phys. Lett. 77, 2767 (2000)]. This leads to the conclusion that the formation mechanism of aligned CNTs depends significantly on the catalyst support material as well as the catalyst material itself. Since the sample bias strongly affected the morphology of CNTs, the selective supply of positive ions to CNT tips was possibly responsible for the alignment of growing CNTs. © 2001 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1382848
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Gas source molecular-beam epitaxy of Si and SiGe using Si2H6 and GeH4 (1991)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 69 (1991), S. 1008-1012 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Gas source molecular-beam epitaxy (MBE) has been studied as a low-temperature Si and SiGe epitaxial method. Specular single-crystalline silicon films were successfully grown by the gas source Si MBE technique at a substrate temperature of about 650 °C. N-type doping was carried out using PH3 gas as a dopant and the maximum electron concentration of 2.9x1019cm−3 was obtained. Furthermore, p-type doping using B2H6 gas was carried out for the first time and the maximum hole concentration of 9.5×1017cm−3 was successfully achieved. The SiGe alloy layer was also grown by the gas source MBE technique using GeH4 as a Ge source gas. The Ge concentration of the sample could be precisely controlled by the molar fraction of Ge in supply and it was increased up to 0.30 with increasing the gas ratio of GeH4 to Si2H6.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.347415
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Extremely low non-alloyed specific contact resistance ρc (10−8 Ω cm2) to metalorganic molecular beam epitaxy grown super heavily C-doped (1021 cm−3) p++GaAs (1991)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 69 (1991), S. 8227-8232 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The specific contact resistance ρc of non-alloyed ohmic metals (Mo/Au and WSix) to p-type GaAs is evaluated by transmission line method (TLM) patterns for various doping concentrations from 8×1018 to 1021 cm−3. The obtained specific contact resistance ρc, less than 10−8 Ω cm2, to metalorganic molecular beam epitaxy grown C-doped ( 1021 cm−3) GaAs is the lowest reported value. From the application point of view for the emitter electrodes of PNp type (two-dimensional electron gas base) heterojunction bipolar transistors, the specific contact resistance of a refractory metal, or the sputter-deposited WSix (x=0.45), is also studied. By reducing the growth temperature of molecular beam epitaxy from 600 to 450 °C and enhancing the As4/Ga flux ratio to 15, a nondiffusive heavily Be doped (1020 cm−3) GaAs is obtained. The specific contact resistance of the WSix to this sample is less than 10−6 Ω cm2. The obtained specific contact resistance can be well explained by a simple modeling based on the tunneling transport of light holes. Secondary ion mass spectroscopy analysis of the depth profile under heat acceleration shows a small diffusion of dopants for Be doped (1020 cm−3) GaAs and C-doped (1021 cm−3) GaAs. In addition, the specific contact resistance ρcISO of the isoheterojunction (p+GaAs/p+AlxGa1−xAs) is also evaluated by TLM patterns.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.347427
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...