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101.
Different N-substituted benzisoselenazol-3(2H)-ones, analogues of ebselen were designed as new antiviral and antimicrobial agents. We report their synthesis, chemical properties as well as study on biological activity against broad spectrum of pathogenic microorganisms (Staphylococcus aureus, Staphylococcus simulans, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Candida albicans, Aspergillus niger) and viruses (herpes simplex virus type 1 (HSV-1), encephalomyocarditis virus (EMCV), vesicular stomatitis virus (VSV)), in vitro. Most of them exhibited high activity against viruses (HSV-1, EMCV) and gram-positive bacteria strains (S. aureus, S. simulans), while their activity against gram-negative bacteria strains (E. coli, P. aeruginosa, K. pneumoniae) was substantially lower. Some of tested compounds were active against yeast C. albicans and filamentous fungus A. niger.  相似文献   
102.
The structure of known copper(II) complex with 4-hydroxybenzoic acid hydrazide has been corrected on the basis of a new X-ray analysis. It has been found, that the sulfate(VI) ion is bonded in apical position of Cu(II) coordination pyramid having two organic ligands at the base. Two water molecules are not coordinated as has been postulated before, but stabilizes the sulfate(VI) group orientation and link the layers of complex molecules by strong hydrogen bonds. The detailed interpretation of the measured IR and Raman spectra has been performed with aid of both: quantum calculations as well as H/D and 63Cu–65Cu isotope substitution.  相似文献   
103.
The paper reports preparation and analytical features of a new Cu(II)-imprinted polymer, based on salen-OMe ligand 2,2′-[ethane-1,2-diylbis(nitrilo(E)methylylidene)]bis(6-allyl-4-methoxyphenol) and styrene-divinylbenzene matrix, as well as its application to on-line preconcentration and flame atomic absorption determination of copper. Sorbent beads (average diameter of 60-80 µm) were obtained using suspension polymerization technique and employed as a column filling. Copper sorption was the most effective at pH 6.8, whereas the highest elution effectiveness was observed when 0.5% HNO3 was applied. The sorbent exhibited good long-term stability and acid resistance. Enrichment factor (EF) of 12 was found for 60 s loading time and loading flow rate of 4 mL min− 1. EF value may be further increased by expanding the loading time and/or flow rate. Batch sorbent capacity in optimal pH conditions was found to be 0.16 mmol g− 1 (9.55 mg g− 1) of a dry polymer. Calcium(II) turned out to be the only significant interferent. Cadmium(II), silver(I), nickel(II), zinc(II) in concentrations lower than about 1 mg L− 1 did not disturb copper(II) preconcentration. Different calibration methods such as: set of standards method (SSM), standard addition method (SAM) and combinatory calibration method (CCM) were employed for copper(II) determination in tap water, spring mineral water and certified reference material. Analysis of EU-H-3 reference material confirmed good accuracy of the proposed method. Relative standard deviation (RSD) was 3.2 for standard addition method and 2.8% for set of standard calibration method. Detection limit for sample consumption 16 mL was 1.03 and 1.07 µgL-1 respectively.  相似文献   
104.
Zusammenfassung Die Bedingungen der Entstehung und der Extraktion der aus Cu2+, Rhodanid und 3,5-Dimethylpyrazol entstehenden Komplexe wurden untersucht. Mittels optischer Untersuchungen wurde bewiesen, daß sich aus diesen Komponenten Triplettkomplexe mit verschiedener Koordinationszahl bilden. Chloroform extrahiert einen Komplex mit der Formel [Cu(CNS)2(DMP)2], Benzol dagegen einen Komplex mit der Formel [Cu(CNS)2(DMP)4].
Summary The conditions for the production and the extraction of complexes formed in the Cu-SCN-DMP system were examined. Optical studies revealed that this system gives rise to triplet complexes with various coordination numbers. Chloroform extracts a complex whose formula is [Cu(SCN)2(DMP)2]. On the other hand, benzene extracts a complex with the formula [Cu(SCN)2(DMP)4].

Résumé On a fait l'étude expérimentale des conditions de formation et d'extraction du complexe qui se forme avec le système Cu/SCN/DMP. Il s'est révélé qu'un complexe triple se formait pour ce système avec un nombre différent de coordination. Le chloroforme extrait un complexe de formule [Cu(SCN)2(DMP)2], le benzène, par contre, un complexe de formule [Cu(SCN)2(DMP)4].
  相似文献   
105.
Zusammenfassung -Dithionaphtholsäure hat komplexbildende Eigenschaften. Der Nickelkomplex löst sich in Äthanol mit violetter Farbe. Seine Zusammensetzung entspricht der Formel (HOC10H6CS2)2Ni. Der Komplex kann zur kolorimetrischen Nickelbestimmung in den Konzentrationsgrenzen 0,20 bis 3,00g/ml verwendet werden.
Summary -Dithionicnaphthol acid has complex-forming properties. The nickel complex dissolves in ethanol to give a violet color. Its composition corresponds to the formula (HOC10H6CS2)2Ni. The complex may be used for the colorimetric determination of nickel within the concentration ranges from 0.20 to 3.00g/ml.

Résumé L'acide -dithionaphtylique possède des propriétés complexantes. Le complexe du nickel se dissout dans l'éthanol en donnant une coloration violette. Sa composition correspond à la formule (HOC10H6CS2)2Ni. On peut l'utiliser pour le dosage colorimétrique du nickel dans le domaine des concentrations 0,20–3,00g/ml.
  相似文献   
106.
Summary A sensitive capillary gas chromatographic method is described for the simultaneous determination of lidocaine, tetracaine, procaine and dibucaine. The method was applied to the determination of anesthetics in tissue homogenates incubated at 38°C at doses between 10 and 400 mg/kg. In the liver tissue thein vitro metabolization of the studied anesthetics is most rapid for tetracaine, also fast for procaine, while for lidocaine and dibucaine the metabolization is very slow. In brain tissue thein vitro metabolization of anesthetics is very slow.The method shows good analytical parameters: linearity between 5 and 40 g/ml; day-to-day reproducibility ca. 8% for a concentration of 20 g/ml, precision ca. 7% for a concentration of 20g/ml. Accuracy is also very good.  相似文献   
107.
We have studied the effect of triphenyl‐lead chloride on the lipid phase of erythrocyte membranes, on lipid monomolecular layers and Na+/K+‐ATPase of the microsomal fraction of rat brain. It was found that the haemolytic effect induced by this compound occurs when its concentration exceeds 30 µM . The minimal lead concentration inducing measurable effects in monomolecular lecithin layers is about 1 µM . Inhibition of Na+/K+‐ATPase activity begins at a concentration exceeding 0.5 µM . Maximum inhibition is observed at around 40 µM —a concentration at which haemolysis also occurs. It can thus be thought that at very low lead concentrations the main (or exclusive) role in modifying membrane function is played by direct interaction between lead and the sulphydryl groups of ATPase, whereas at higher concentrations two effects seem to overlap: direct interaction between lead and enzymic proteins via their sulphydryl groups and as indirect influence on the proteins via changes in the organization of the lipid phase of the membrane. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   
108.
From reactions involving M{N(SiMe3)2}3 (M = La, Pr and Eu) and triflurotertiary butano[(CF3)Me2COH; tftb.H], the compounds [La(tftb)3(thf)1.5] (1), [Pr(tftb)3 (2) and [Eu(tftb)3] (3) have been isolated. From variable temperature 1H and 19F NMR studies it is suggested that 1 is a mixture of [La3(tftb)9(thf)2] (1a) and [La2(tftb)6(thf)4] (1b). X-ray crystallography has shown that 2 is the trimer [Pr3(tftb)9] and variable temperature 1H and 19F NMR suggests that 3 is also a trimer, [Eu3(tftb)9].  相似文献   
109.
110.
The hemolytic toxicity of tributyllead (TBL) and triphenyllead (TPhL) chlorides and its prevention by dithiotreitol (DTT), diethylenetriaminepentamethylenephosphonic acid pentasodium (PMP) and sodium disulfide (Na2S) was studied. It was found that both TBL and TPhL efficiently hemolyzed pig erythrocytes when used in micromolar concentrations; tributyllead chloride being about twice more efficient than triphenyllead chloride. The hemolytic efficiency of these compounds was blocked by PMP, DTT and Na2S in a concentration-dependent manner. However, significant differences in anti-hemolytic efficiency of these compounds were found. Namely, DTT and Na2S were very efficiently protecting erythrocytes against the action of organoleads, while the PMP protection was weak. Also, differences between DTT and Na2S protective efficiency were found. They more efficiently prevented erythrocyte hemolysis by TPhL than by TBL. Moreover, erythrocytes were better protected against the action of TBL by Na2S than by DTT. Such differentiation may be connected with possible differences in localization of the organolead compounds and protective agents in the erythrocyte membrane. To check these possibilities a series of experiments was performed using the fluorescence technique and various fluorimetric probes. These measurements enabled to determine fluidity changes induced in erythrocyte membranes by the organoleads and the protective compounds and to formulate some remarks concerning the differences in the mechanism of interaction of the organoleads with these membranes.  相似文献   
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