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41.
Sava? S?nmezo?lu Güven ?ankaya Necmi Serin 《Applied Physics A: Materials Science & Processing》2012,107(1):233-241
Nanostructured TiO2 thin films were deposited on quartz glass at room temperature by sol–gel dip coating method. The effects of annealing temperature
between 200∘C to 1100∘C were investigated on the structural, morphological, and optical properties of these films. The X-ray diffraction results
showed that nanostructured TiO2 thin film annealed at between 200∘C to 600∘C was amorphous transformed into the anatase phase at 700∘C, and further into rutile phase at 1000∘C. The crystallite size of TiO2 thin films was increased with increasing annealing temperature. From atomic force microscopy images it was confirmed that
the microstructure of annealed thin films changed from column to nubbly. Besides, surface roughness of the thin films increases
from 1.82 to 5.20 nm, and at the same time, average grain size as well grows up from about 39 to 313 nm with increase of the
annealing temperature. The transmittance of the thin films annealed at 1000 and 1100∘C was reduced significantly in the wavelength range of about 300–700 nm due to the change of crystallite phase. Refractive
index and optical high dielectric constant of the n-TiO2 thin films were increased with increasing annealing temperature, and the film thickness and the optical band gap of nanostructured
TiO2 thin films were decreased. 相似文献
42.
Munshi G Mustafa Sudhir Raniwala T Awes B Rai RS Bhalerao JG Contreras RV Gavai SK Ghosh P Jaikumar GC Mishra AP Mishra H Mishra B Mohanty J Nayak J-Y Ollitrault SC Phatak L Ramello R Ray PK Sahu AM Srivastava DK Srivastava VK Tiwari 《Pramana》2006,67(5):961-981
This is the report of Heavy Ion Physics and Quark-Gluon Plasma at WHEPP-09 which was part of Working Group-4. Discussion and
work on some aspects of quark-gluon plasma believed to have created in heavy-ion collisions and in early Universe are reported. 相似文献
43.
L. Bertanza A. Bigi P. Calafiura M. Calvetti R. Carosi M. C. Carrozza R. Casali C. Cerri R. Fantechi I. Mannelli V. M. Marzulli A. Nappi G. M. Pierazzini L. Tassi G. D. Barr P. Buchholz D. Coward D. Cundy N. Doble L. Gatignon P. Grafström R. Hagelberg H. Wahl K. J. Peach T. Beier H. Blümer R. Heinz K. Kleinknecht B. Panzer-Steinde B. Renk H. Rohrer J. Scheidt J. Staeck A. Wagner E. Augé D. Fournier L. Iconomidou-Fayard O. Perdereau A. C. Schaffer L. Serin M. Holder A. Kreutz R. Werthenbach 《Zeitschrift fur Physik C Particles and Fields》1997,73(4):629-632
A precision measurement of the K S mean lifetime has been performed by comparing, in the same experimental setup, the distributions of two-pion decays of neutral kaons produced by high energy proton-beryllium interactions in two targets at a relative distance variable between 112 and 160 m. The value obtained combining the results from π+π? and π0π0 decays is τs = (0.8971 ± 0.0021) 10?10 s. 相似文献
44.
KB McTiernan SC Jarvis D Allen R Bol D Scholefield 《Rapid communications in mass spectrometry : RCM》1999,13(18):1803-1807
The composition of dissolved organic matter (DOM) in a soil is the product of a variety of soil processes. Changes in the composition of DOM in water discharged from soil should, therefore, give an important insight into modifications in these soil processes. We hypothesise that these processes in soils, under different grassland management regimes, would be affected to different extents by the short-term disturbance of a storm event and that evidence of this could be detected in delta(13)C and delta(15)N signatures in drainage and surface runoff waters. During a storm event we collected discharge waters from 1 ha grassland lysimeters, with or without artificial drainage, which received contrasting fertiliser inputs, and delta(13)C and delta(15)N signatures were determined. Changes in (13)C enrichment during the storm event were clearly identifiable, as were differences between plots for (13)C and (15)N, illustrating that this technique has potential to be a useful tool for identifying and investigating short- and long-term changes in soil organic matter dynamics. Copyright 1999 John Wiley & Sons, Ltd. 相似文献
45.
We study the inventory management problem of a service center operating in a decentralized service parts network. The service centers collaborate through inventory and service pooling, and through sharing information on the inventory status. Upon demand arrival, a service center may request a part from the other center, in which case a payment is made. Under this competitive and collaborative environment, we first characterize the optimal operating policy of an individual service center. Through computational analysis we identify the conditions under which pooling is most beneficial to the service center, and make an assessment of different pooling strategies which are commonly adopted in practice and in the literature. Finally, we analyze the effect of interaction between the centers on the benefit of pooling. 相似文献
46.
47.
In this study, the forward bias current–voltage (I–V) and capacitance–voltage (C–V) characteristics of the Al/TiO2/p-Si (MIS) structures derived using the sol–gel method have been investigated and compared at various preparation temperatures.
Experimental results show that the preparation temperatures strongly affect the electrical characteristics, such as ideality
factor (n), zero-bias barrier height (), series resistance (R
s
) and interface states (N
ss
). The MIS structures show non-ideal behavior of I–V characteristics with an n varying between 2.17 and 4.61. We have found that the and R
s
increase as the n decrease with increasing preparation temperature. The energy distribution profile of N
ss
of the Al/TiO2/p-Si (MIS) structures was obtained from the forward bias I–V characteristics by taking into account both the bias dependence of the effective barrier height () and R
s
for various preparation temperatures. The values of N
ss
increase from the midgap towards the top of valance band for various preparation temperatures. 相似文献
48.
N. Serin 《Applied Physics A: Materials Science & Processing》1985,36(4):209-212
We developed a method for the determination of the minority carrier diffusion coefficient by means of the capacitance-voltage characteristics of a Schottky barrier. Capacitance-voltage-frequency characteristics were measured at room temperature and liquid nitrogen temperature. We adapted the diffusion capacitance concept ofp-n junction for the metal/semiconductor rectifier contact. We determined the minority carrier diffusion coefficient as 47–61 cm2/s. 相似文献
49.
This study investigated the effect of the substrate temperature on the structural, optical, morphological, and electrical properties of undoped SnO2 films prepared by a spray deposition method. The films were deposited at various substrate temperatures ranging from 300-500 °C in steps of 50 °C and characterized by different optical and structural techniques. X-ray diffraction studies showed that the crystallite size and preferential growth directions of the films were dependent on the substrate temperature. These studies also indicated that the films were amorphous at 300 °C and polycrystalline at the other substrate temperatures used. Infrared and visible spectroscopic studies revealed that a strong vibration band, characteristic of the SnO2 stretching mode, was present around 630 cm−1 and that the optical transmittance in the visible region varied over the range 75-95% with substrate temperature, respectively. The films deposited at 400 °C exhibited the highest electrical conductivity property. 相似文献
50.
Azo compounds were prepared by the reaction between benzenediazonium chloride and 4-amino-5-hydroxy-2,7-naphthalenedisulfonic
acid monosodium salt under alkaline conditions. Two new azo-linked Schiff base ligands, 4-(3-methoxysalicylidene)-5-hydroxy-6-(2-hydroxyphenylazo)-2,7-naphthalene
disulfonic acid disodium salt (H2L) and 4-(3-methoxysalicylidene)-5-hydroxy-6-(2-hydroxy-4-cholorophenylazo)-2,7-naphthalenedisulfonic acid disodium salt (H2L1), have been synthesized. Also, the new CuII, NiII and CoII complexes of the azo-linked Schiff base ligands were prepared and characterized by infrared spectra, UV–Vis, 1H- and 13C-n.m.r., attached proton test (APT) and distortionless enhancement by polarization transfer (DEPT) and atomic absorption
spectroscopy, mass spectrocopy, elemental analyses, thermogravimetric analysis, conductivity and magnetic measurements. It
was determined that the synthesized ligands were comprised of six-membered rings due to intramolecular hydrogen bonding. The
results suggested that condensation of the azo-derivative compounds and o-vanillin in a 1:1 molar ratio produces mononuclear Schiff base ligands with an ONO donor set. Preliminary histological studies
were made. Magnetic moment studies showed that all complexes have a tetrahedral configuration. 相似文献