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161.
In present contribution a study is presented, where fluid dynamic measurements are used to observe multiphase flow pattern in a bioreactor. It can be shown that hydrodynamic effects have a major influence on the formation, shape and size of Granular Activated Sludge (GAS) in a Sequencing Batch Reactor (SBR) under aerobic condition. In order to analyse multiphase flow pattern (water, air, granules) in the bioreactor in-situ techniques with optical measurements are applied. LASER IIIB and video lamp are used as a light source. Due to a transient spatial velocity distribution in the bioreactor our experiments are carried out in different levels of SBR. Tracer particles are employed to visualise the fluid flow pattern. Velocity field of the liquid phase in the bioreactor is determined by use of PIV method (Particle Image Velocimetry). PTV (Particle Tracking Velocimetry) is implemented to observe velocity field of individual granules (solid phase). (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
162.
Sam Benson Antonio Fernandez Nicole D. Barth Fabio deMoliner Mathew H. Horrocks C. Simon Herrington Jose Luis Abad Antonio Delgado Lisa Kelly Ziyuan Chang Yi Feng Miyako Nishiura Yuichiro Hori Kazuya Kikuchi Marc Vendrell 《Angewandte Chemie (International ed. in English)》2019,58(21):6911-6915
The transport and trafficking of metabolites are critical for the correct functioning of live cells. However, in situ metabolic imaging studies are hampered by the lack of fluorescent chemical structures that allow direct monitoring of small metabolites under physiological conditions with high spatial and temporal resolution. Herein, we describe SCOTfluors as novel small‐sized multi‐colored fluorophores for real‐time tracking of essential metabolites in live cells and in vivo and for the acquisition of metabolic profiles from human cancer cells of variable origin. 相似文献
163.
164.
Juan Luis Delgado de la Cruz 《Tetrahedron letters》2006,47(22):3715-3718
A diethynylbenzene monomer substituted with two fullerene moieties has been prepared, and its oligomerization performed in the presence of phenylacetylene as end-capping reagent afforded the corresponding end-capped mono- and di-mer with an oligo(phenylenebutadiyndiyl) (OPB) conjugated backbone substituted with two and four fullerene subunits, respectively. 相似文献
165.
A synthesis of the title compound, operable on kilogram scale, employs reductive acetylation of an N-acylindazole to give a hemiaminal acetate followed by deacetoxylation to the corresponding N-alkylindazole. 相似文献
166.
We have studied the total reflection regime through a model represented by a region separating two dielectric bulk media with well-defined refraction indexes. This region is considered to be an interface in which the following hypotheses are established: – Refraction index linear variation with the transition from one medium to the other. – The thickness depends on the optical phenomenon supposedly produced in the interface. The results we obtained were in close agreement with those obtained by authors who have studied this regime through a fundamentally different treatment. 相似文献
167.
C. Cedeño J.M. Delgado L.M. de Chalbaud 《Journal of Physics and Chemistry of Solids》2005,66(11):2049-2051
Fe2In2Se5, a polytype of FeIn2Se4 (a material belonging to the II □ III2 VI4 family of semiconducting compounds) has been synthesized by conventional solid-state reaction of their constituent elements. The product of the reaction was sequentially used as starting material in the crystal growth process carried out by chemical transport using I2 as transporting agent. The crystal structure of a new polytype of this compound was determined using single crystal techniques with data collected with a CCD-based diffractometer. The successful indexing of the data and refinement of the structure led to an hexagonal unit cell with a=4.0371(4) and c=32.746(4) Å. Although the absorption effect in the data was quite noticeable, because of the layered morphology exhibited by the material, a good agreement was obtained for a structural model similar to the structure reported for a related polytype belonging to the ZnIn2S4 system. 相似文献
168.
Three different finite-difference routines were compared for solving the nonlinear, coupled, partial differential and algebraic equations that describe pressure swing adsorption processes. A successive substitution method (SS), a block LU decomposition procedure (BLUD), and the method of lines approach with adaptive time stepping (DASSL) were used to simulate and compare the computation times required to reach the periodic state for two different PSA systems: PSA-air drying and PSA-solvent vapor recovery. For both systems, the results showed that DASSL was nearly twice as fast as BLUD, whereas SS was nearly an order of magnitude slower than BLUD. DASSL and BLUD were also very robust and accurate, as nearly identical bed profiles were obtained from both methods under both transient and periodic state conditions. 相似文献
169.
Araujo K Colina M Mazurek R Delgado J Ledo H Gutierrez E Herrera L 《Analytical and bioanalytical chemistry》1996,355(3-4):319-320
The mercury concentrations in wastewater and sewage sludge of a stabilization pond system have been evaluated. The system is built by three parallel facultative ponds followed by two systems of three maturation ponds in series. The samples of wastewater and sludge were digested using nitric acid and placed into a Parr-type bomb for 4 h at 110 degrees C. Mercury was measured by Cold Vapour Atomic Absorption Spectrometry (CV-AAS) at 253.7 nm with sodium tetrahydroborate as reductant. The methodologies were checked with an USEPA quality control sample, a standard reference material from NIST and with another method of mineralization (cold mineralization) showing good results. Concentrations of mercury in wastewater between 1.47 +/- 0.75 microgl(-1) have been found at the entrance of the system and 0.74 +/- 0.0 microgl(-1) at the exit, while in sludge the results were between 0.29 +/- 0.12 microgkg(-1) in the facultative pond and 0.04 +/- 0.02 microgkg(-1) in the second maturation pond (exit). 相似文献
170.
Vimont A Lavalley JC Sahibed-Dine A Otero Arean C Rodríguez Delgado M Daturi M 《The journal of physical chemistry. B》2005,109(19):9656-9664
By hydrolysis of an ethanolic gallium nitrate solution, gamma-Ga2O3 was prepared as a single-phase polymorph having a specific surface area of 160 m2 g(-1). Surface acidity and basicity of this material was studied by IR spectroscopy, using pyridine, 2,6-dimethylpyridine, acetonitrile, and carbon dioxide as spectroscopic probe molecules. For comparison, a gamma-Al2O3 sample having a surface area of 290 m2 g(-1) was also studied. On partially hydroxylated gamma-Ga2O3, the main O-H stretching bands were found at 3693 (sharp) and at 3660-3630 cm(-1) (broad), and the material proved (by adsorbed dimethylpyridine) to have a weak Br?nsted acidity. Surface Lewis acidity of gamma-Ga2O3 was revealed (mainly) by adsorbed pyridine, which gave the characteristic IR absorption bands of Lewis-type adducts at 1612, 1579, 1488, and 1449 cm(-1) (values noted under an equilibrium pressure of 1 Torr at room temperature); the corresponding Lewis acid centers (coordinatively unsaturated Ga3+ ions) were found to be weaker, although more abundant, than those present on the surface of gamma-Al2O3 (unsaturated Al3+ ions). Another significant difference between gamma-Ga2O3 and gamma-Al2O3 is the smaller thermal stability of pyridine and 2,6-dimethylpyridine Lewis adducts formed on the gallium oxide. The surface basicity of gamma-Ga2O3 was studied by using carbon dioxide and deuterated acetonitrile as IR probe molecules. Adsorbed CO2 gave carbonate and hydrogen-carbonate surface species similar to those formed by gamma-Al2O3. Adsorbed acetonitrile gave rise to acetamide species, which revealed the basic character of surface O2- ions. These acetamide species were found to be more abundant on gamma-Ga2O3 than on gamma-Al2O3. 相似文献