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
  • 1
    Electronic Resource
    Electronic Resource
    Effects of Zn ion on magnetic properties of Fe3O4 magnetic colloids (abstract) : The 40th annual conference on magnetism and magnetic materials (1996)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 79 (1996), S. 6035-6035 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The effects of Zn ion on magnetic properties Fe3O4 magnetic colloids were investigated in this study. Fe3O4 magnetic colloids were produced by the chemical coprecipitation method, i.e., mixing an acidic solution containing FeCl2⋅4H2O, FeCl3⋅6H2O, ZnCl2⋅4H2O, with a NaOH alkali solution at 70 °C, and then centrifuging them from the mixed solution. Various reaction times, solution pH values, and Zn ion contents were also used. Fe3O4 magnetic fluid was obtained by adding ammonium oleate into the mixed solution, precipitating the colloids from the solution, neutralizing the colloids by hydrochloric acid, and dispersing the colloids in n-hexane. XRD, EDX, TEM, and VSM were used to determine the structure, chemical compositions, particle sizes, and magnetic properties of the colloids and the magnetic fluid. The spinel colloids was easily form at a higher pH value in solutions where the pH value ranged from 7 to 12. Fe3O4 colloids were completely formed within the first minute of mixing and the particle size of Fe3O4 colloids did not increase with time after the first minute.The lattice parameter of Fe3O4 colloids increased linearly with the Zn ion content because the diameter of Zn ion is larger than that of Fe ions. The particle size of Fe3O4 colloids was found to be 10 nm by TEM. For an initially fixed Zn content of 8 wt % in solutions, the Zn content in the Fe3O4 colloids ranged from 3.32 wt % at pH=5 to a maximum value of 7.85 wt % at pH=10. Later, it reduced to 7.51 wt % at pH=12 because Zn ion has the lowest solubility at pH=10. At 8 wt % of zinc ion in the solution, the σs of the Fe3O4 colloid increase sharply from 0 at pH=3 to 92 emu/g at pH=8 and then reach a maximum value of 94 at pH=10. The σs value and Hc value of the Fe3O4 colloid were found significantly improved by adding a suitable amount of Zn ions, e.g., ranging from 70 emu/g and 48 Oe at Zn=0 wt % to a maximum 94 emu/g and 50 Oe at Zn=7.14 wt %. Later they reduced to 70 emu/g and 44 Oe at Zn=12.52 wt % when prepared at pH=10. The σs value of the magnetic fluid was found linearly proportional to the colloid content in the magnetic fluid. For a colloid containing 7.51 wt % of Zn ion, the σs value of the magnetic fluid is 9.8 emu/g at 25 wt % of colloid. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.362081
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Mid-infrared interband cascade lasers with quantum efficiencies 〉200% (1998)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 72 (1998), S. 2220-2222 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: An external differential quantum efficiency exceeding 200% has been observed from 4 μm InAs/InGaSb/AlSb interband cascade lasers under 1 μs pulses and 0.1% duty cycle at 80 K. By increasing the pulse lengths and the repetition rates, average powers 〉16 mW have been measured with 5 μs pulses at 10% duty cycle, the internal quantum efficiency and the internal loss are determined to be 220% and 14 cm−1, respectively. © 1998 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.121265
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    High power mid-infrared interband cascade lasers based on type-II quantum wells (1997)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 71 (1997), S. 2409-2411 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We report a high power mid-infrared interband cascade laser operating at temperatures up to 170 K. The threshold current densities of this laser are considerably lower than the previously reported values in cascade lasers. The structure was grown by molecular beam epitaxy on a GaSb substrate and comprises 23 periods of active regions separated by digitally graded multilayer injection regions. A peak optical output power of ∼0.5 W/facet and a slope of 211 mW/A per facet, corresponding to a differential external quantum efficiency of 131%, are observed at 80 K and at a wavelength of ∼3.9 μm. © 1997 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.120076
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    New grating fabrication technology for optoelectronic devices: Cascaded self-induced holography (1995)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 67 (1995), S. 3072-3074 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: A method of fabricating submicron gratings for optoelectronic devices from a glass mask was proposed and demonstrated. The glass mask has gratings on both sides with a period of at least four times of the final feature size. By modifying the grating periods on the mask, one can achieve multiple-period gratings with a very fine period spacing for advanced wavelength division multiplexing (WDM) devices. In this letter, we demonstrated 0.5 μm second-order gratings for 1.55 μm distributed-feedback lasers and gratings with a 6 A(ring) period difference for WDM laser arrays using only optical sources. © 1995 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.114868
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Dielectric properties of metal-organic chemical vapor deposited highly textured Pb(ScTa)1−xTixO3 (x=0–0.3) relaxor ferroelectric thin films on LaNiO3 electrode buffered Si (1999)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 75 (1999), S. 2485-2487 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Highly (100) textured Pb(ScTa)1−xTixO3 (x=0–0.3) thin films were grown on LaNiO3/Pt/Ti electrode-coated Si substrate using metal-organic chemical vapor deposition at 685 °C. Ti addition was introduced to modify the dielectric properties. Diffuse phase transition, typical of relaxor ferroelectrics was noticed. As Ti content increased from 0% to 30%, the phase transition temperature (Tmax) gradually shifted from −10 to 120 °C with the dielectric constant at Tmax increased from 1397 to 1992 (1 kHz). Loss tangent values are generally below 0.025. © 1999 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.125056
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Type II mid-infrared quantum well lasers (1996)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 68 (1996), S. 2976-2978 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Pulsed, optically pumped four-constituent Type-II (InAs-Ga1−xInxSb-InAs-AlSb) quantum well lasers emitting at 3.9–4.1 μm were observed to lase up to 285 K with a characteristic temperature T0 of 35 K for 170 K ≤Top≤270 K. A theoretical analysis predicts dramatic further improvements once the potential for suppressing Auger recombination is fully realized. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.116374
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Three-dimensional P-wave Velocity Structure of the Bear Valley Region of Central California (1997)
    Springer
    Pure and applied geophysics 149 (1997), S. 667-688 
    Details
    ISSN: 1420-9136
    Keywords: Key words: 3-D velocity structure, circular ray tracing, San Andreas Fault, seismicity.
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract —The three-dimensional P-wave velocity structure of the Bear Valley region of central California is determined by applying a circular ray-tracing technique to 1735 P-wave arrivals from 108 locally recorded earthquakes. Comparison of the results obtained from one-dimensional and laterally varying starting models shows that many of the features in the structure determined are fairly insensitive to the choice of the starting model. Velocities associated with the Gabilan granites southwest of the San Andreas Fault are slightly higher than those in the Franciscan formation to the northeast, and these two features are separated in the southern part of the region by a narrow fault zone with very low velocities. In the southeastern part of the region, where the Gabilan granites do not abut the San Andreas Fault, the low velocities of the fault zone cross over to the southwestern side of the fault. They also appear to extend to depths of at least 15km, thus locally reversing the contrast across the San Andreas Fault that prevails farther to the northwest. In the northwestern part of the region, the low velocities of the fault zone split and follow the surface traces of the San Andreas and Calaveras Faults, but do not appear to extend to depths much deeper than about 6km. There also appears to be a well-defined contrast in structure in the middle of the Santa Clara Valley, suggesting the existence of a fault in the basement of the valley that may be a southern extension of the Sargent Fault into this region. Relocated hypocenters beneath the San Andreas Fault cluster in a zone that dips about 80° southwest and intersects the surface trace of the fault in the southern part of region.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s000240050046
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Generation of high-order rotational lines by four-wave Raman mixing using a high-power picosecond Ti:Sapphire laser (1996)
    Springer
    Applied physics 63 (1996), S. 121-124 
    Details
    ISSN: 1432-0649
    Keywords: 42.65 ; 51.70
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract More than thirty rotational lines equally spaced by 587 cm−1 are generated simultaneously in the vicinity of the fundamental line by four-wave Raman mixing using a high-power picosecond Ti:Sapphire laser as a pump source and hydrogen as a Raman medium. Since the wavelength of this multifrequency laser emission extends from the near-infrared to the near-ultraviolet, it can be utilized as a tunable light source for picosecond spectroscopy. Because of the wide spectral bandwidth available, this procedure has great potential for the generation of ultrashort laser pulses by mode-locking these emission lines.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01095260
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Congenital bilateral agenesis of diaphragm: report of a case (1997)
    Springer
    European journal of pediatrics 156 (1997), S. 572-574 
    Details
    ISSN: 1432-1076
    Keywords: Key words Congenital diaphragmatic hernia ; Pulmonary hypoplasia ; Pancreas fibrosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Bilateral agenesis of the diaphragm is a rare, life-threatening malformation. Infants with this defect rarely survive to have surgical intervention. We report a 32-week premature female infant who was born to a 36-year-old mother via vaginal delivery. The pregnancy course was complicated by hypertension and polyhydramnios. Cytogenetic study showed a normal 46 XX female karyotype. She had cyanosis, respiratory distress and scaphoid abdomen at birth. A roentgenograph confirmed the diagnosis of diaphragmatic hernia. Surgery was performed at 21 h of age. Bilateral agenesis of diaphragm, herniation of abdominal organs and oesophagus and pulmonary hypoplasia were noted. Furthermore, stomach and spleen were adherent to the mediastinum and vertebrae. The patient developed hypotension and persistent hypoxaemia and expired at age of 26 h. Autopsy revealed bilateral agenesis of diaphragm, hypoplasia of lungs, and pancreas fibrosis with mild hypoplasia of islets of Langerhans. Conclusion Bilateral agenesis of diaphragm associated with pancreas fibrosis is a rare entity, and its clinical significance needs further investigation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004310050666
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Shade effects on forage crops with potential in temperate agroforestry practices (1998)
    Springer
    Agroforestry systems 44 (1998), S. 109-119 
    Details
    ISSN: 1572-9680
    Keywords: cool-season forages ; grasses ; heat stress ; legumes ; light ; shade ; warm-season forages
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Thirty forages, including eight introduced cool-season grasses, four native warm-season grasses, one introduced warm-season grass, eight introduced cool-season legumes, five native warm-season legumes, and four introduced warm-season legumes, were grown in 7.6 L (two gallon) pots in full sun, 50%, and 80% shade created by shade cloth over a greenhouse frame. Experiments were conducted during summer--fall 1994, spring--early summer 1995, and summer--fall 1995. A complete randomized experimental design was used and above ground dry weight was measured in each shade environment. Tukey's studentized range test was used to compare mean dry weights (MDW) within a species. Warm-season grasses displayed significant reductions in MDW under shade regardless of growing season. All cool-season forages grown during spring--early summer showed a decrease in MDW under shade; however, the reductions in dry weights of ‘Benchmark’ and ‘Justus’ orchardgrass, ‘KY 31’ tall fescue, Desmodium canescens and D. paniculatum were not significant under 50% shade. Cool-season grasses showed more shade tolerance when grown during the summer--fall than when grown during the spring--early summer. Seven of the selected cool-season grasses grown during the summer--fall did not display significant reductions in MDW under 50% shade as compared to full sun. Smooth bromegrass grown under 50% shade showed a significantly increased MDW production compared to growth in full sun. With the exception of Justus orchardgrass and smooth bromegrass, growth of cool-season grasses was inhibited at 80% shade. Among the legumes harvested during the fall, the dry weights of both Desmodium species tested and hog peanut (Amphicarpaea bracteata L.) increased significantly under 50% and 80% shade. In addition, ‘Cody’ alfalfa, white clover, slender lespedeza and ‘Kobe’ lespedeza showed no significant reductions in MDW under 50% shade.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006205116354
    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...