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101.
Daisuke Nagai Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》2009,47(3):653-657
1H‐Quinazoline‐2,4‐diones, which are key intermediates in the synthesis of medicines, were successfully synthesized from 2‐aminobenzonitriles by the fixation of CO2 in the presence of a polystyrene derivative bearing amidine moiety [poly(amidine)]. A model reaction, that is, the reaction of 2‐aminobenzonitrile ( 1a ) with CO2 in the presence of N‐methyltetrahydropyrimidine ( MTHP ) revealed that a catalytic amount of MTHP afforded 1H‐quinazoline‐2,4‐dione ( 2a ) quantitatively at atmospheric pressure. Several 1H‐quinazoline‐2,4‐diones ( 2a ‐ 2c ) were successfully synthesized from the corresponding 2‐aminobenzonitriles ( 1a ‐ 1c ) in the presence of poly(amidine). The poly(amidine) could easily be separated from the reaction mixture by filtration and reused in subsequent reactions owing to the heterogeneous system. These demonstrated that poly(amidine) is a useful heterogeneous polymer‐supported reagent for the synthesis of 1H‐quinazoline‐2,4‐diones from CO2. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 653–657, 2009 相似文献
102.
Hideaki Asaka Yutaka Kukita Taisuke Yonomoto Yasuo Koizumi Kanji Tasaka 《Experimental Thermal and Fluid Science》1990,3(6):588-596
Three 0.5% cold-leg small-break loss-of-coolant accident (SBLOCA) experiment were conducted at the ROSA-IV Large Scale Test Facility (LSTF) to investigate the effects of break orientation on system thermal-hydraulic responses. In these three experiments, the break hole was located at the side, bottom, and top of the horizontal cold leg, respectively. Although the key phenomena observed in the three experiments were basically the same, the break flow rate was affected by the break orientation when phase stratification occured in the cold leg; the break flow rate was largest for the side break and smallest for the top break. The RELAP5/MOD2 code failed to predict the difference in the break flow rate observed in the experiments. Modification to the break flow calculation models, for both subcooled and two-phase flow discharge conditions, resulted in good agreement between data and predictions. 相似文献
103.
T Tanase N Murakami S Nagai T Ueda J Sakakibara H Ando Y Hotta K Takeya 《Chemical & pharmaceutical bulletin》1992,40(2):327-332
Three aromatic compounds (2-4) possessing a carbomethoxyl group or a dimethoxyphthaloyl group, prepared by the Diels-Alder reaction of the cardiac glycoside, proscillaridin (1), with dimethyl acetylenedicarboxylate and methyl propiolate, were transformed into alcohols, carboxylic acids and amides. The biological activities of the resulting derivatives were evaluated by the use of Na+, K(+)-adenosine triphosphatase (Na+,K(+)-ATPase) from dog kidney and isolated guinea-pig papillary muscle. Although the biological activities of the resulting derivatives were less potent than that of 1, a para-substituted benzylalcohol (5), methylbenzamides (9a and 10a), and ethylbenzamides (9b and 10b) inhibited the activity of Na+,K(+)-ATPase almost as potently as naturally occurring cardiac glycosides such as digoxin and digitoxin. 相似文献
104.
A rapid and sensitive sialidase assay method based on peroxidase-labeled peanut lectin (PNA) binding to desialylated erythrocyte is described. Formalinized sheep erythrocytes were used both as a stable substrate for sialidase and as a target for the lectin. In the case of sialidases from Vibrio cholerae and Arthrobacter ureafaciens, a linear relationship was observed between the amount of peroxidase-labeled PNA bound to erythrocytes and the enzyme amount. Binding of the lectin to sialidase-treated erythrocytes was completely prevented in the presence of 25 mM lactose and galactose. The method is particularly useful as a selective assay for sialidase which is active towards gangliosides or sialoglycoproteins, because a mammalian sialidase which is preferentially active towards sialooligosaccharides and sialoglycopeptides is not able to remove sialic acid from erythrocytes. 相似文献
105.
Kazukiyo Nagai Lora G. Toy Benny D. Freeman Masahiro Teraguchi Giseop Kwak Toshio Masuda Ingo Pinnau 《Journal of Polymer Science.Polymer Physics》2002,40(19):2228-2236
The gas permeability and n‐butane solubility in glassy poly(1‐trimethylgermyl‐1‐propyne) (PTMGP) are reported. As synthesized, the PTMGP product contains two fractions: (1) one that is insoluble in toluene and soluble only in carbon disulfide (the toluene‐insoluble polymer) and (2) one that is soluble in both toluene and carbon disulfide (the toluene‐soluble polymer). In as‐cast films, the gas permeability and n‐butane solubility are higher in films prepared from the toluene‐soluble polymer (particularly in those films cast from toluene) than in films prepared from the toluene‐insoluble polymer and increase to a maximum in both fractions after methanol conditioning. For example, in as‐cast films prepared from carbon disulfide, the oxygen permeability at 35 °C is 330 × 10?10 cm3 (STP) cm/(cm2 s cmHg) for the toluene‐soluble polymer and 73 × 10?10 cm3 (STP) cm/(cm2 s cmHg) for the toluene‐insoluble polymer. After these films are conditioned in methanol, the oxygen permeability increases to 5200 × 10?10 cm3 (STP) cm/(cm2 s cmHg) for the toluene‐soluble polymer and 6200 × 10?10 cm3 (STP) cm/(cm2 s cmHg) for the toluene‐insoluble polymer. The rankings of the fractional free volume and nonequilibrium excess free volume in the various PTMGP films are consistent with the measured gas permeability and n‐butane solubility values. Methanol conditioning increases gas permeability and n‐butane solubility of as‐cast PTMGP films, regardless of the polymer fraction type and casting solvent used, and minimizes the permeability and solubility differences between the various films (i.e., the permeability and solubility values of all conditioned PTMGP films are similar). © 2002 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 40: 2228–2236, 2002 相似文献
106.
The utility of the absorption promoters, sodium glycocholate (GC-Na), ethylenediamine dihydrochloride (EDTA-2Na), sodium caprylate (Cap-Na) and sodium salicylate (Sal-Na), in the intranasal administration of human fibroblast interferon-beta (HuIFN-beta) in rabbits was investigated. The optimal amount of added EDTA-2Na, Cap-Na and Sal-Na with respect to HuIFN-beta was examined for nasal absorption in the powder dosage form. Formulations of HuIFN-beta with GC-Na showed greatly enhanced intranasal HuIFN-beta absorption, as compared to the other absorption promoters. The results of a stability study on HuIFN-beta in homogenates of nasal mucosa suggested that GC-Na behaved as a hydrolysis inhibitor in the nasal mucosa and maintained the activity of HuIFN-beta. 相似文献
107.
108.
György Bázár Zoltan Kovacs Mariko Tanaka Akane Furukawa Airi Nagai Manami Osawa Yukari Itakura Hiroshi Sugiyama Roumiana Tsenkova 《Analytica chimica acta》2015
Near infrared spectroscopy is an overtone spectroscopy regarded as a quick and non-destructive method that provides analytical solutions for components that represent approximately 1% or more of the total mass of the investigated composite samples. Aquaphotomics offers the possibility for disentanglement of information remaining hidden in the spectra when conventional data evaluation methods are used, since this concept utilizes changes of the water structure induced by the measured solute as specific molecular vibrations at water bands. Here, near infrared technique and aquaphotomics are applied for non-destructive identification and quantification of mono- and di-saccharide solutes at 100–0.02 mM concentration that is accepted as unachievable with near infrared spectroscopy. The results presented in this study support the aquaphotomics' water molecular mirror concept that explores spectral changes related to water molecular rearrangements caused by minute changes of the solutes in the aqueous systems. The method provides quick and accurate alternative for classical analytical measurements of saccharides even at millimolar concentration levels. 相似文献
109.
The passages of vapor flow and the returning liquid flow, are perfectly partitioned in a separate thermosyphon. Therefore the flooding limit can be eliminated, and practicability based on its construction is highly evaluated. In the present work, a container tube made of heat resisting glass, in which an electric heater is inserted, is selected as the heating section of the experimental equipment. Distilled water is used as the working fluid. The influence of the heater type, the diameter of evaporating section and the liquid fill charge on the heat transfer performance have been studied. The larger heat transfer coefficient is achieved in the case of the U type heater, the larger tube diameter and the less liquid fill charge of the evaporating section. The useful correlation equations of the heat transfer coefficient in the evaporator have been derived.
Experimentelle Untersuchung an einem Trennstrom-Thermosiphon
Zusammenfassung In einem Trennstrom-Thermosiphon sind die Strömungskanäle für die Dampfströmung und den Kondensatrücklauf vollkommen separiert. Die Flutgrenze kann deshalb unberücksichtigt bleiben. In dieser Untersuchung dient ein temperaturbeständiges Glasrohr mit innenliegender Heizung als Wärmequelle. Arbeitsmedium ist destilliertes Wasser. Untersucht wurden der Einfluß des Heizelementtyps, des Durchmessers der Verdampferstrecke und der Füllmenge auf das Wärmeüber-gangsverhalten. Das U-Typ Heizelement liefert bei größerem Rohrdurchmesser und geringerer Füllmenge in der Verdampferstrecke die höchsten Wärmeübergangskoeffizienten. Für diese wurden Korrelationsgleichungen aufgestellt.相似文献
110.
Miyabe K 《Analytical sciences》2011,27(10):1007-1017
New moment equations were developed for chromatography using superficially porous (shell-type) spherical particles, which have recently attracted much attention as one of separation media for fast separation with high efficiency. At first, the moment equations of the first absolute and second central moments in the real time domain were derived from the analytical solution in the Laplace domain of a set of basic equations of the general rate model of chromatography, which represent the mass balance, mass-transfer rate, and reaction kinetics in the column packed with shell-type particles. Then, the moment equations were used for analyzing the experimental data of chromatography of kallidin in a Halo column, which were published in a previous paper written by other researchers. It was tried to predict the chromatographic behavior of shell-type particles having different shell thicknesses. The new moment equations are useful for a detailed analysis of the chromatographic behavior of shell-type spherical particles. It is also concluded that they can be used for the preliminarily optimization of their structural characteristics. 相似文献