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471.
The influence of the temperature of secondary annealing, stimulating the formation of optically and electrically active centers,
on the erbium ion electroluminescence (EL) at λ≈1.54 μm in (111) Si:(Er,O) diodes has been studied. The diodes were fabricated
by the implantation of 2.0 and 1.6 MeV erbium ions at doses of 3×1014 cm−2 and oxygen ions (0.28 and 0.22 MeV, 3×1015 cm−2). At room temperature, the EL intensity in the breakdown mode grows with the annealing temperature increasing from 700 to
950°C. At annealing temperatures of 975–1100°C, no erbium EL is observed in the breakdown mode owing to the formation of microplasmas.
The intensity of the injection EL at 80 K decreases with the annealing temperature increasing from 700 to 1100°C.
__________
Translated from Fizika i Tekhnika Poluprovodnikov, Vol. 35, No. 10, 2001, pp. 1224–1227.
Original Russian Text Copyright ? 2001 by Sobolev, Emel’yanov, Nikolaev. 相似文献
472.
To predict residual and thermal stresses which occur during water quenching of solid cylindrical rod and ring cross-sectioned steel tubes, a finite element technique has been used. The variations of residual stresses on different surfaces and cross-sections, e.g. in the radial, axial and tangential directions have been examined, and the effect of internal diameter of tubes on residual stress was investigated. The results show that the residual stresses act as a compressive force along the cooling surface and then by moving away from the surface begin to decrease and reverse their sign, near the centre of the cylinder are subjected to tensile stresses. Because of the reversal of the sign of stress, the effective stress goes to a minimum at some distance from the frontal surface and this may be vital since lower plastic deformation may cause cracking failure. As in solid cylinder, in cylindrical tubes also, the frontal and the upper cooling surface has significant effect on the stress distribution. From the comparison of the residual stress distributions of solid cylinder and cylindrical tubes and using their individual stress maps it was seen that they vary considerably along different cooling surfaces, especially at the frontal surface. 相似文献
473.
Si:(Er,O)-based tunnel light-emitting diodes were fabricated and exhibited the shortest ever recorded characteristic rise
time for erbium electroluminescence. This is due to the formation of Er-related centers with an effective excitation cross
section for erbium ions of ∼7×10−16 cm2 and an excited-state lifetime of ∼17 μs. The lifetime of the first excited state of erbium ions after turning off the reverse
current was measured for the first time; this lifetime is associated with Auger energy transfer to free electrons in the electrically
neutral region of the diode.
__________
Translated from Fizika i Tekhnika Poluprovodnikov, Vol. 34, No. 8, 2000, pp. 965–969.
Original Russian Text Copyright ? 2000 by Emel’yanov, Sobolev, Trishenkov, Khakuashev. 相似文献
474.
V. Yu. Davydov V. V. Lundin A. N. Smirnov N. A. Sobolev A. S. Usikov A. M. Emel’yanov M. I. Makoviichuk E. O. Parshin 《Semiconductors》1999,33(1):1-5
The influence of rapid-anneal conditions and subsequent coimplantation of oxygen ions on the photoluminescence of erbium ions
implanted with an energy of 1 MeV and dose of 5×1014 cm−2 in MOCVD-grown GaN films is investigated. The erbium photoluminescence intensity at a wavelength ∼ 1.54 μm increases as the
fixed-time (15 s) anneal temperature is raised from 700 °C to 1300 °C. The erbium photoluminescence intensity can be increased
by the coimplantation of oxygen ions at anneal temperatures in the indicated range below 900 °C. The transformation of the
crystal structure of the samples as a result of erbium-ion implantation and subsequent anneals is investigated by Raman spectroscopy.
Fiz. Tekh. Poluprovodn. 33, 3–8 (January 1999) 相似文献
475.
N. A. Sobolev E. I. Shek A. M. Emel’yanov V. I. Vdovin T. G. Yugova 《Semiconductors》1999,33(6):610-612
The photoluminescence spectra and behavior of the structural defects in layers obtained by implanting 1.0–1.8-MeV Er and Dy
ions at a dose of 1×1013 cm−2 are investigated after annealing at 1000–1200 °C for 0.5–1 h in argon or a chlorine-containing atmosphere. The structural
defects are studied using transmission electron microscopy and selective chemical etching. The dominant features in the luminescence
spectra of the Si:Er and Si:Dy layers following annealing in the chlorine-containing atmosphere are lines associated with
the formation of edge dislocations, while the dominant features following the annealing of Si:Er and Si:Dy layers in argon
are the erbium-related lines. A comparative analysis of the luminescence spectra of the Si:Er and Si:Dy layers shows that
the highest intensity of dislocation-related luminescence is achieved in the erbium-implanted structures. A significant influence
of intrinsic point defects on the structural and optical properties of erbium-and dysprosium-implanted silicon is revealed.
Fiz. Tekh. Poluprovodn. 33, 656–659 (June 1999) 相似文献
476.
N. A. Sobolev V. V. Lundin V. I. Sakharov I. T. Serenkov A. S. Usikov A. M. Emel’yanov 《Semiconductors》1999,33(6):624-626
The effect of annealing on the optical and structural properties of gallium nitride layers grown by metalorganic chemical
vapor deposition and implanted with 0.8 to 2.0-MeV erbium ions at doses of (1−4)×1014 cm−2 is investigated. Additional implantation of 0.11 to 0.28-MeV oxygen ions at doses of (1−4)×1015 cm−2 is performed on some samples. Measurements of the Rutherford backscattering of protons show that amorphization of the gallium
nitride layers does not occur at the erbium implantation doses investigated. The formation of erbium-related luminescence
centers which emit at 1.54 μm ends before the defect structure of the implanted layers is restored during a postimplantation
anneal in the temperature range 700–1300 °C.
Fiz. Tekh. Poluprovodn. 33, 674–676 (June 1999) 相似文献
477.
Rıza Atav Bürhan Buğdaycı Ayşe Şen Uğur Ergünay Pelin Gürkan Ünal Emel Özkan Ünal Gökmen Karagöz Raziye Işık M. İhsan Soysal Muhittin Özder Sezen Arat Büşra Eroğlu 《Coloration Technology》2023,139(6):689-702
Today, the need for quality wool suitable for worsted fabric production in the world is mainly met by Australian merino wool. In Turkey, which has a significant sheep population, in addition to domestic breeds, approximately 10% of the total sheep population (around four million head) is composed of merino cross breeds. However, the fleece quality is far from meeting Australian merino wool standards. Therefore, the aim of this study is to ensure a merino herd with high-quality wool in Turkey. For this aim, by carrying out field studies in the Thrace region of Turkey where Turkish Merino sheep are widely bred, sheep with fleece that can meet the demands of the worsted industry were determined. As a result of field studies in which thousands of sheep were examined, it was determined that 43 female and 10 male sheep had fleece that would meet these standards. Then the breeders of the sheep, which had quality fleece, were persuaded and these sheep were purchased, and “Turkey's wool-oriented Turkish (Karacabey) Merino Herd” consisting of 30 sheep and three rams was formed in the farm of Tekirdağ Namık Kemal University. In the second part of this study, a 100% wool fabric produced by using Australian merino was taken as a reference and it was aimed to produce the same fabric from Turkish merino wool. For this aim, the wool-oriented Turkish Merino herd, which was bred at the university farm for 1 year, was shorn in May 2022. Then, Turkish and Australian merino wools were first converted into worsted yarn and then into woven fabric. The results of mechanical (tensile strength, pilling, abrasion resistance, felting shrinkage, Hofmann dimensional change, bending stiffness) and dyeability (dye-uptake, CIE L*a*b* and colour yield (K/S) values; washing, rubbing and light fastness values) properties of fabrics produced from Turkish and Australian merino wool is presented. 相似文献