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101.
Seawater bittern (nigari) is a concentrated solution remaining after the crystallization process of salt that has been used as a coagulant for tofu. Recently, various nigari products are distributed in the East Asia. To clarify the properties of nigari products, major mineral composition of six nigari products was determined. Then, effects of the nigari on the browning and antioxidant activity during the glucose/lysine Maillard reaction were investigated. Though the predominant cation was Mg2+, the content was varied by each product (0.88–6.49 mol/L). The other major ion contents were also varied. Each 0.5 mol/L of d-glucose and l-lysine were incubated with the nigari (5–50 % (v/v)) or nigari-related salts (1 or 2 mol/L). The browning (OD at 465 nm) and antioxidant activity (1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging capacity and ferrous-reducing power) were increased remarkably by the nigari containing high Mg2+ content. The browning tended to be high with sulfates (Na2SO4, (NH4)2SO4). On the other hand, high content of MgCl2 decreased slightly the browning and antioxidant activity. These results suggest that the reaction and antioxidant activities were affected not only by salinity and cations but also by anions and other elements in the nigari. 相似文献
102.
Ana Paula A. Marques Marcos Takashi S. Tanaka Elson Longo Edson R. Leite Ieda Lucia Viana Rosa 《Journal of fluorescence》2011,21(3):893-899
SrMoO4 doped with rare earth are still scarce nowadays and have attracted great attention due to their applications as scintillating
materials in electro-optical like solid-state lasers and optical fibers, for instance. In this work Sr1−xEuxMoO4 powders, where x = 0.01; 0.03 and 0.05, were synthesized by Complex Polymerization (CP) Method. The structural and optical
properties of the SrMoO4:Eu3+ were analyzed by powder X-ray diffraction patterns, Fourier Transform Infra-Red (FTIR), Raman Spectroscopy, and through Photoluminescent
Measurements (PL). Only a crystalline scheelite-type phase was obtained when the powders were heat-treated at 800 °C for 2 h,
2θ = 27.8° (100% peak). The excitation spectra of the SrMoO4:Eu3+ (λEm. = 614 nm) presented the characteristic band of the Eu3 + 5L6 transition at 394 nm and a broad band at around 288 nm ascribed to the charge-transfer from the O (2p) state to the Mo (4d)
one in the SrMoO4 matrix. The emission spectra of the SrMoO4:Eu3+ powders (λExc. = 394 and 288 nm) show the group of sharp emission bands among 523–554 nm and 578–699 nm, assigned to the 5D1→7F0,1and 2 and 5D0→7F0,1,2,3 and 4, respectively. The band related to the 5D0→7F0 transition indicates the presence of Eu3+ site without inversion center. This hypothesis is strengthened by the fact that the band referent to the 5D0→7F2 transition is the most intense in the emission spectra. 相似文献
103.
Takanari Togashi Mitsuo Umetsu Takashi Naka Satoshi Ohara Yoshiharu Hatakeyama Tadafumi Adschiri 《Journal of nanoparticle research》2011,13(9):3991-3999
The assembly of metal oxide nanoparticles (NPs) on a biomolecular template by a one-pot hydrothermal synthesis method is achieved
for the first time. Magnetite (Fe3O4) nanoneedles (length: ~100 nm; width: ~10 nm) were assembled on cyclic-diphenylalanine (cFF) nanorods (length: 2–10 μm; width:
200 nm). The Fe3O4 nanoneedles and cFF nanorods were simultaneously synthesized from FeSO4 and l-phenylalanine by hydrothermal synthesis (220 °C and 22 MPa), respectively. The samples were analyzed by powder X-ray diffraction
(XRD), Fourier transform infrared spectroscopy (IR), transmission electron microscopy (TEM), and superconducting quantum interference
device (SQUID) magnetometry. Experimental results indicate that Fe3O4 nanoneedles were assembled on cFF nanorods during the hydrothermal reaction. The composite contained 3.3 wt% Fe3O4 nanoneedles without any loss of the original magnetic properties of Fe3O4. 相似文献
104.
Yasuaki Ueki Takashi Torigoe Hirofumi Ono Ryo Yoshiie Joseph H. Kihedu Ichiro Naruse 《Proceedings of the Combustion Institute》2011,33(2):1795-1800
Gasification technology is recognized as one of the possibilities for utilizing biomass effectively. This study focused on woody biomass gasification fundamentals, using a bench-scale packed-bed reactor. In this experiment, pellets of black pine were gasified, using air as the oxidizing agent. Gasification tests were carried out under both updraft and downdraft conditions. Temperature distributions and compositions of syngas inside the gasifier were continuously monitored during gasification experiments at several ports on the wall of the reactor. The syngas at the exit of the gasifier was also sampled to estimate the amount of tar. Lower heating values of the syngas under updraft and downdraft conditions were 4.8 and 3.8 MJ/m3N, respectively. It was easier to control the height of the packed bed under the downdraft condition than under the updraft condition. Under the updraft condition, a bridging phenomenon occurred. Tar generation under the downdraft condition was lower than that under the updraft condition. This is because tar passes through a partial combustion zone or higher temperature zone in the downdraft gasifier. 相似文献
105.
Peter Hockicko Peter Bury Peter Sidor Hikaru Kobayashi Masao Takahashi Takashi Yanase 《Central European Journal of Physics》2011,9(1):242-249
A set of MOS structures with thin SiO2 layers prepared by nitric acid oxidation (NAOS) method was investigated using acoustic deep level transient spectroscopy
(A-DLTS) to explain the role of annealing treatment (post-oxidation annealing (POA) and post-metallization annealing (PMA))
at different conditions on the distribution of interface states. The activation energies of interface states and the corresponding
capture cross-section were calculated both from Arrhenius plots constructed for individual peaks of the A-DLTS spectra and
applying the method of modeling of measured acoustic spectra. The energy distribution of the interface states was determined
also from the dependence of acoustoelectric response signal (ARS) on the external bias voltage (U
ac
- V
G
curves). By comparing the A-DLTS spectra, U
ac
- V
G
characteristics and some electrical measurements (G-V, I-V curves) of investigated MOS structures with no treatment with those treated with POA and/or PMA, the role of individual treatments
was observed. The definite decrease of the interface states in the structures with the PMA treatment in comparison with the
POA treatment was confirmed too. 相似文献
106.
In the present paper, we obtain new results on universality as applications of hybrid universality and almost-periodicity in its half-plane of absolute convergence. By using these, we show the universality for Euler products of Igusa type, Euler-Zagier multiple zeta-functions and Tornheim-Hurwitz type of double zeta-functions. 相似文献
107.
In this work, a new flow regime transition model is proposed for two-phase flows in a vertical annulus. Following previous works, the flow regimes considered are bubbly (B), slug (S) or cap-slug (CS), churn (C) and annular (A). The B to CS transition is modeled using the maximum bubble package criteria of small bubbles. The S to C transition takes place for small annulus perimeter flow channels and it is assumed to occur when the mean void fraction over the entire region exceeds that over the slug–bubble section. If the annulus perimeter is larger that the distorted bubble limit the cap-slug flow regime will be considered since in these conditions it is not possible to distinguish between cap and partial-slug bubbles. The CS to C transition is modeled using the maximum bubble package criteria. However, this transition considers the coalescence of cap and spherical bubbles in order to take into account the flow channel geometry. Finally, the C to A transition is modeled assuming two different mechanisms, (a) flow reversal in the liquid film section along large bubbles; (b) destruction on liquid slugs or large waves by entrainment or deformation. In the S to C and C to A flow regime transitions the annulus flow channel is considered as a rectangular flow channel with no side walls. In all the modeled transitions the drift-flux model is used to obtain the final correlations. The final equations for every flow regime transition are easy to be implemented in computational codes and not experimental input is needed. The prediction accuracy of the newly developed model has been checked against air–water as well as boiling flow regime maps. In all the cases, the new developed model shows better predicting capabilities than the existing correlations most used in literature. 相似文献
108.
Doaa H. M. Alsaadi Aedla Raju Ken Kusakari Faruk Karahan Nazim Sekeroglu Takashi Watanabe 《Molecules (Basel, Switzerland)》2020,25(23)
The growth and quality of licorice depend on various environmental factors, including the local climate and soil properties; therefore, its cultivation is often unsuccessful. The current study investigated the key factors that affect the contents of bioactive compounds of Glycyrrhiza glabra L. root and estimated suitable growth zones from collection sites in the Hatay region of Turkey. The contents of three bioactive compounds (glycyrrhizic acid, glabridin, and liquiritin), soil factors (pH, soil bearing capacity, and moisture content), and geographical information (slope, aspect, curvature, elevation, and hillshade) were measured. Meteorological data (temperature and precipitation) were also obtained. An analysis of variance (ANOVA) and multivariate analysis of variance (MANOVA) were performed on the data. The soil bearing capacity, moisture content, slope, aspect, curvature, and elevation of the study area showed statistically significant effects on the glycyrrhizic acid and liquiritin contents. A habitat suitability zone map was generated using a GIS-based frequency ratio (FR) model with spatial correlations to the soil, topographical, and meteorological data. The final map categorized the study area into four zones: very high (15.14%), high (31.50%), moderate (40.25%), and low suitability (13.11%). High suitability zones are recommended for further investigation and future cultivation of G. glabra. 相似文献
109.
Jin Su Takashi Hisatomi Tsutomu Minegishi Kazunari Domen 《Angewandte Chemie (International ed. in English)》2020,59(33):13800-13806
Most CdTe photoanodes and photocathodes show positive and negative photocurrent onset potentials for water oxidation and reduction, respectively, and are thus unable to drive photoelectrochemical (PEC) water splitting without external applied biases. Herein, the activity of a CdTe photoanode having an internal p‐n junction during PEC water oxidation was enhanced by applying a CdCl2 annealing treatment together with surface modifications. The resulting CdTe photoanode generated photocurrents of 1.8 and 5.4 mA cm?2 at 0.6 and 1.2 VRHE, respectively, with a photoanodic current onset potential of 0.22 VRHE under simulated sunlight (AM 1.5G). The CdCl2 annealing increased the grain sizes and lowered the density of grain boundaries, allowing more efficient charge separation. Consequently, a two‐electrode tandem PEC cell comprising a CdTe‐based photoanode and photocathode split water without any external bias at a solar‐to‐hydrogen conversion efficiency of 0.51 % at the beginning of the reaction. 相似文献
110.
Takeshi Yamada Yuki MizutaniYoshihide Umebayashi Naoko InnoMaiko Kawashima Takashi KikuchiReiko Tanaka 《Tetrahedron letters》2014
Tandyukisin (1), a novel decalin derivative with an enolic β-ketoaldehyde, has been isolated from a strain of Trichoderma harzianum OUPS-111D-4 originally derived from the marine sponge Halichondria okadai, and its structure has been elucidated on the basis of spectroscopic analyses using 1D and 2D NMR techniques. In addition, the absolute configuration for 1 was established by the application of CD spectrum to the tribenzoate derivative. This compounds exhibited moderate cytotoxicity against human cancer cell lines. 相似文献