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21.
The theory of integration over infinite-dimensional spaces is known to encounter serious difficulties. Categorical ideas seem to arise naturally on the path to a remedy. Such an approach was suggested and initiated by Segal in his pioneering article (Segal, Bull Am Math Soc 71:419–489, 1965). In our paper we follow his ideas from a different perspective, slightly more categorical, and strongly inspired by the point-free topology. First, we develop a general (point-free) concept of measurability (extending the standard Lebesgue integration when applying to the classical σ-algebra). Second (and here we have a major difference from the classical theory), we prove that every finite-additive function μ with values in [0,1] can be extended to a measure on an abstract σ-algebra; this correspondence is functorial and yields uniqueness. As an example we show that the Segal space can be characterized by completely canonical data. Furthermore, from our results it follows that a satisfactory point-free integration arises everywhere where we have a finite-additive probability function on a Boolean algebra. 相似文献
22.
Veara Loha Aleš Prokop Liping Du Robert D. Tanner 《Applied biochemistry and biotechnology》1999,79(1-3):701-712
Foam fractionation isone of the low operating-cost techniques for removing proteins from a dilute solution. The initial bulk
solution pH and air superficial velocity play an importantrole in the foam-fractionation process. Denaturation of proteins
(enzymes) can occur, however, during the foamfractionation process from the shear forces resulting from bursting air bubbles.
At the extreme bulk solution pHs (lower than 3.0 and higher than 10.0), the en zymatic activity of cellulase in the foamate
phase drops significantly. Within these two pH boundsan increase in the air superficial velocity, Vo, and a decrease in the bulk solution pH leads to a decrease in the separation ratio (SR), defined as theratio of the protein
concentration in the foamate to the protein concentration in the residue. On the other hand, an increase in Vo provides a higher foamate-protein recovery. The process efficiency is defined as the product of foamate-protein recovery
times the SR times the cellulase activity. The optimal operating condition of the cellulase foamfractionation process is taken
into account at the maximum value of the processefficiency. In this study, that optimal condition is atan air superficial
velocity of 32 cm/min and a bulk-solution pH of 10.0. At this condition, the recovered foamate is about 80% of the original
protein mass, the SR is about 12, and the en zymatic activity is about 60% of the original cellulase activity. 相似文献
23.
Jan Turek Zdeňka Růžičková Eva Tloušťová Helena Mertlíková‐Kaiserová Jana Günterová Lubomír Rulíšek Aleš Růžička 《应用有机金属化学》2016,30(5):318-322
Two gold(I) complexes of the (NHC)AuX type bearing a triazole‐based N‐heterocyclic carbene (NHC) ligand (1‐tert‐butyl‐4‐(4‐methylphenyl)‐3‐phenyl‐1H‐1,2,4‐triazol‐4‐ium‐5‐ylidene) and various halide ligands (X = Br, I) were synthesized and characterized in solution using NMR spectroscopy as well as in the solid state using X‐ray diffraction techniques. The cytotoxic properties of both compounds and the precursor, (NHC)AuCl, were screened against a panel of human tumour cell lines including liver cancer (HepG2), cervical cancer (HeLa S3) and leukaemia (CCRF‐CEM, HL‐60) and compared to cisplatin and auranofin. It was found that the activities of the chloro and bromo derivatives were generally superior to that of cisplatin and slightly less effective compared to auranofin, except for HepG2 cells where auranofin was not as effective. In addition, the ability to induce membrane phosphatidyl serine externalization as a hallmark of apoptosis in CCRF‐CEM leukaemic cells was investigated. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
24.
Tomáš Řezníček Libor Dostál Aleš Růžička Jiří Kulhánek Filip Bureš Roman Jambor 《应用有机金属化学》2011,25(3):173-179
The phosphines L1PPh2 (1) and L2PPh2 (2) containing different Y,C,Y‐chelating ligands, L1 = 2,6‐(tBuOCH2)2C6H3? and L2 = 2,6‐(Me2NCH2)2C6H3?, were treated with PdCl2 and di‐µ‐chloro‐bis[2‐[(N,N‐dimethylamino)methyl]phenyl‐C,N]‐dipalladium(II) and yielded complexes trans‐{[2,6‐(tBuOCH2)2C6H3]PPh2}2PdCl2 (3), {[2,6‐(Me2NCH2)2C6H3]PPh2} PdCl2 (4), {[2,6‐(tBuOCH2)2C6H3]PPh2}Pd(Cl)[2‐(Me2NCH2)C6H4] (5) and {[2,6‐(Me2NCH2)2C6H3]PPh2}Pd(Cl)[2‐(Me2NCH2)C6H4] (6) as the result of different ability of starting phosphines 1 and 2 to complex PdCl2. Compounds 3–6 were characterized by 1H, 13C, 31P NMR spectroscopy and ESI‐MS. The molecular structures of 3,4 and 6 were also determined by X‐ray diffraction analysis. The catalytic activity of complexes 3–6 was evaluated in the Suzuki‐Miyaura cross‐coupling reaction. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
25.
26.
High Performance Liquid Chromatography/Electrochemistry/High Resolution Electrospray Ionization‐Mass Spectrometry (HPLC/EC/HR ESI‐MS) Characterization of Selected Cytokinins Oxidation Products 下载免费PDF全文
Michal Karady Ondřej Novák Aleš Horna Miroslav Strnad Karel Doležal 《Electroanalysis》2015,27(2):406-414
Electrochemistry combined with mass spectrometry represents an emerging analytical technique used to study the oxidation pathway of various drugs and in vivo occurring compounds, continuously showing a capability to generate many known metabolites or new oxidation products. An on‐line HPLC/EC/HR ESI‐MS method had been used to investigate the oxidation of selected cytokinin compounds. This setup allowed rapid identification and general structure elucidation of the obtained products. An electrochemical oxidation of isopentenyladenine resulted in five products, including hydroxylated and dehydrogenated products, which correlates very well with its in vivo metabolism. Electrochemical conversion of trans‐zeatin revealed six products, with two dehydrogenation products corresponding to its in vivo occurring metabolites. cis‐Zeatin oxidation in the electrochemical cell gave rise to eight products, resembling similarity to trans‐zeatin oxidation. All three compounds underwent a complete turnover mainly through two oxidation reactions occurring in the electrochemical cell? dehydrogenation and a less typical aliphatic hydroxylation. The resulting products are in correlation with their known in vivo metabolism. 相似文献
27.
This study investigated the potential use of waste cooking oil (WCO) in the production of engine fuels and valuable chemicals via catalytic cracking. WCO was processed in its pure form and in a mixture with hydrotreated vacuum gas oil (HVGO). Catalytic cracking experiments were performed using a microactivity test (MAT) (simulation of the fluid catalytic cracking environment). In cracking over the standard fluid catalytic cracking equilibrium catalyst (FCC-ECAT), the oxygen contained in the feed was consumed in the formation of CO and CO2, water and into oxygenated organic compounds (phenolics, esters, carboxylic acids, etc.), which were found in the organic phase of the liquid product. In order to remove the unwanted organic oxygenates, the catalytic system based on pure FCC-ECAT was modified by addition of the ZSM-5-based FCC catalyst. By using the mixture containing FCC-ECAT and 10 mass % of FCC-ZSM-5, it was possible to reduce the amount of organic oxygenates to almost the feasible minimum when cracking pure WCO. The effect of the catalyst mixture on cracking the feed mixture of the vacuum gas oil with 10 vol. % of WCO was manifested in the practically zero formation of organic oxygenates and in a gasoline yield comparable with vacuum gas oil (VGO) cracking. 相似文献
28.
Generalizing the obvious representation of a subspace \({Y \subseteq X}\) as a sublocale in Ω(X) by the congruence \({\{(U, V ) | U\cap Y = V \cap Y\}}\), one obtains the congruence \({\{(a, b) |\mathfrak{o}(a) \cap S = \mathfrak{o}(b) \cap S\}}\), first with sublocales S of a frame L, which (as it is well known) produces back the sublocale S itself, and then with general subsets \({S\subseteq L}\). The relation of such S with the sublocale produced is studied (the result is not always the sublocale generated by S). Further, we discuss in general the associated adjunctions, in particular that between relations on L and subsets of L and view the aforementioned phenomena in this perspective. 相似文献
29.
Michal Karady Ondřej Novák Aleš Horna Miroslav Strnad Karel Doležal 《Electroanalysis》2011,23(12):2898-2905
On‐line LC‐EC/ESI‐MS has been established as a fast and simple method to mimic some types of oxidation reaction of various drugs and to study the formation and structure of the resulting products. This technique has been applied to a 2,6,9‐trisubstituted purine, R‐roscovitine, which is known to be an inhibitor of some cyclin‐dependent kinases (CDKs) and a potential anticancer drug. Oxidation of R‐roscovitine in an electrochemical cell (EC), operated under various conditions, resulted in appearance of 6 major products. These were further analyzed by high‐resolution mass spectrometry, their structures were elucidated by accurate mass measurement and compared to previously identified R‐roscovitine in vitro/in vivo metabolites. Although none of the observed products was structurally identical to those identified previously in vitro/in vivo, all of them, except for the methoxylated products, resembled similarity due to appearing through the same reaction type. R‐roscovitine in the EC cell underwent N‐dealkylation of the isopropyl moiety, hydroxylation of the aromatic side‐chain, dihydroxylation, methoxylation and dimer formation. The hydroxylation product was identified as Olomoucine II, a R‐roscovitine derivative, which displays 10‐times higher CDK‐inhibiting activity than R‐roscovitine and the occurrence of which, as R‐roscovitine product, has not yet been observed in vitro/in vivo. 相似文献
30.
Gericke M Doliška A Stana J Liebert T Heinze T Stana-Kleinschek K 《Macromolecular bioscience》2011,11(4):549-556
In the present study, blood-compatible PET surfaces were prepared by coating with anticoagulant cellulose sulfates that were synthesized homogeneously in ionic liquids. The adsorption behavior of polysaccharides on PET films was investigated using QCM-D. It was demonstrated that pre-coating with different amino-group-containing polysaccharides improves the affinity toward cellulose sulfate. Moreover, the effect of different degrees of sulfation on the adsorption process was evaluated. Based on these results, several layer-by-layer coated PET foils were prepared that showed significantly improved blood compatibility compared to the initial untreated material. 相似文献