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21.
Ljubi?a Balanovi? Dragan Manasijevi? Dragana ?ivkovi? Aleksandra Mitovski Nade?da Talijan Du?ko Mini? ?ivan ?ivkovi? 《Journal of Thermal Analysis and Calorimetry》2012,110(1):221-226
The knowledge of the phase diagram of the Al?CGe?CZn ternary system is of importance in the development of high temperature soldering materials. In this study, the phase diagram of the Al?CGe?CZn ternary system was calculated by the calculation of phase diagrams method using binary thermodynamic parameters included in the COST MP0602 thermodynamic database. Chosen alloys with compositions along two vertical sections with molar ratio Al/Ge?=?3/1 and 1/3 were measured using DTA (differential thermal analysis). The experimentally determined phase transition temperatures from this work and phase equilibria data from literature were compared with calculation results and good mutual agreement was noticed. 相似文献
22.
Regina Janciene Ausra Vektariene Zita Stumbreviciute Lidija Kosychova Kazimieras Konstantinavicius Benedikta D. Puodziunaite 《Monatshefte für Chemie / Chemical Monthly》2003,44(1):1629-1639
Highly substituted, novel, 8- and 9-nitro-2,3,4,5-tetrahydro-1,5-benzodiazepin-2(1H)-ones were obtained by direct nitration of the 7-bromo-5-trifluoroacetyl (or formyl)-substituted tetrahydrobenzodiazepinones. Alkaline and acidic hydrolysis of the novel mononitro derivatives was examined. Semiempirical AM1 calculations of aromatic substituents orientation in the nitration products are presented. 相似文献
23.
Structural basis for thrombin activation of a protease-activated receptor: inhibition of intramolecular liganding 总被引:3,自引:0,他引:3
Seeley S Covic L Jacques SL Sudmeier J Baleja JD Kuliopulos A 《Chemistry & biology》2003,10(11):1033-1041
Protease-activated G protein-coupled receptors (PAR1-4) are tethered-ligand receptors that are activated by proteolytic cleavage of the extracellular domain (exodomain) of the receptor. PAR1, the prototypic member of the PAR family, is the high-affinity thrombin receptor of platelets and vascular endothelium and plays a critical role in blood coagulation, thrombosis, and inflammation. Here, we describe the solution structure of the thrombin-cleaved exodomain of PAR1. The side chains of a hydrophobic hirudin-like (Hir) sequence and adjacent anionic motif project into solution. Docking of the exodomain Hir sequence to exosite I of thrombin reveals that the tethered ligand in the cleaved exodomain bends away from thrombin, leaving its active site available to another large macromolecular substrate. The N-terminal ligand is longer than anticipated and forms an intramolecular complex with a region located in the C terminus of the exodomain. Mutational analysis confirmed that this C-terminal region is a ligand binding site for both intra- and intermolecular ligands. A lipidated-ligand binding site peptide was found to be an effective inhibitor of thrombin-induced platelet aggregation. 相似文献
24.
25.
Ašperger Danijela Ćurković Lidija Horvat Alka J. M. Kaštelan-Macan Marija 《平面色谱法杂志一现代薄层色谱法》2014,27(2):84-87
JPC – Journal of Planar Chromatography – Modern TLC - Qualitative identification of Cu, Sn, Pb, Ni, and Fe in Cu-alloys is presented. The method involves anodic sampling of alloys,... 相似文献
26.
Lidija Fras Zemljič Per Stenius Janne Laine Karin Stana-Kleinschek 《Cellulose (London, England)》2008,15(2):315-321
Adsorption of carboxymethyl cellulose (CMC) as a method to introduce charged (ionizable) groups onto cellulose cotton fibre
surfaces was investigated. The method was based on application of a previously published method used for wood fibres. The
amount of adsorbed ionizable groups was determined indirectly by analysis of CMC in solution by the phenol–sulphuric acid
method and directly by conductometric titration of the fibres. Results from the two methods correlated well. The molecular
weight and purity of the CMC had an influence on its adsorption onto cotton; high molecular weight CMC was preferentially
adsorbed. The adsorbed charge correlated linearly with the amount of CMC adsorbed. The total charge of the cotton fibres could
be increased by more than 50% by adsorption of CMC. It is expected that this modification procedure can be used in a wide
spectrum of practical applications.
Lidija Fras Zemljič and Karin Stana-Kleinschek are the members of the European Polysaccharide Network of Excellence (EPNOE). 相似文献
27.
Tomislav P. Živković 《Journal of mathematical chemistry》2008,43(2):518-600
Interaction of a finite quantum system that contains ρ eigenvalues and eigenstates with an infinite quantum system that contains a single one-parameter eigenvalue band is considered. A new approach for the treatment of the combined system
is developed. This system contains embedded eigenstates with continuous eigenvalues , and, in addition, it may contain isolated eigenstates with discrete eigenvalues . Two ρ × ρ eigenvalue equations, a generic eigenvalue equation and a fractional shift eigenvalue equation are derived. It is shown that all properties of the system that interacts with the system can be expressed in terms of the solutions to those two equations. The suggested method produces correct results, however
strong the interaction between quantum systems and . In the case of the weak interaction this method reproduces results that are usually obtained within the formalism of the
perturbation expansion approach. However, if the interaction is strong one may encounter new phenomena with much more complex
behavior. This is also the region where standard perturbation expansion fails. The method is illustrated with an example of
a two-dimensional system that interacts with the infinite system that contains a single one-parameter eigenvalue band. It is shown that all relevant completeness relations are satisfied,
however strong the interaction between those two systems. This provides a strong verification of the suggested method. 相似文献
28.
Ljubiša Balanović Dragana Živković Dragan Manasijević Duško Minić Bata Marjanović 《Journal of Thermal Analysis and Calorimetry》2013,111(2):1431-1435
The results of calorimetric study and thermal analysis of binary Al–Sn system are presented in this paper. The Oelsen calorimetry was used in thermodynamic analysis. Following thermodynamic properties were determined at 727 °C: activities, activity coefficients, partial/integral molar Gibbs excess, and mixing energies. The energetics of mixing in liquid Al–Sn alloys has been analyzed through the study of concentration fluctuation in the long-wavelength limit. Thermal analysis of selected alloys in Al–Sn system was done using differential thermal analysis. Defined characteristic phase transition temperatures were used for comparison with calculated phase diagram of investigated system. Good agreement with available literature data was obtained. Structural analysis of selected alloys was done using optic microscopy. 相似文献
29.
Regina Janciene Zita Stumbreviciute Ausra Vektariene Lidija Kosychova Romualdas Sirutkaitis Algirdas Palaima Zita Staniulyte Benedikta D. Puodziunaite 《Heteroatom Chemistry》2008,19(1):72-81
A number of 1‐substituted 4H,5H,6H‐[1,3]thiazolo[3,2‐a][1,5]benzodiazepinium‐11‐bromides and S‐(2‐oxo‐2‐phenyl‐X‐(p)‐ethyl)‐3‐(2‐methyl‐1H‐benzimidazol‐1‐yl) propane (or butane) thioate hydrobromides were obtained by direct reaction of the 5‐acetyl(or formyl, or anilinocarbonyl)‐substituted tetrahydro‐1,5‐benzodiazepine‐2‐thiones with aromatic α‐bromoketones. 2‐[(1‐Acetyl‐2(or 3)‐methyl‐2,3‐dihydro‐1H‐1,5‐benzodiazepin‐4‐yl) sulfanyl]‐1‐phenylethanones as intermediates of the formation of thiazolo [3,2‐a][1,5]benzodiazepine and N‐substituted 2‐methyl‐1H‐benzimidazole derivatives have been synthesized. Semiempirical AM1 calculations of a mechanism and energetic parameters for the heptatomic nucleus rearrangement to benzimidazole ring are presented. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:72–81, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20414 相似文献
30.
Digital microfluidics based on electrowetting-on-dielectric (EWOD) has recently emerged as one of the most promising technologies to realize integrated and highly flexible lab-on-a-chip systems. In such EWOD-based digital microfluidic devices, the aqueous droplets have traditionally been manipulated either directly in air or in an immiscible fluid such as silicone oil. However, both transporting mediums have important limitations and neither offers the flexibility required to fulfil the needs of several applications. In this paper, we report on an alternative mode of operation for EWOD-based devices in which droplets enclosed in a thin layer of oil are manipulated in air. We demonstrate the possibility to perform on-chip the fundamental fluidic operations by using such water-oil core-shell droplets and compare systematically the results with the traditional approach where the aqueous droplets are manipulated directly in air or oil. We show that the core-shell configuration combines several advantages of both the air and oil mediums. In particular, this configuration not only reduces the operation voltage of EWOD-based devices but also leads to higher transport velocities when compared with the manipulation of droplets directly in air or oil. 相似文献