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11.
HKUST‐1‐Cu synthesized in the presence and absence of P‐123 trough solvotermal method. After characterization using some different microscopic and spectroscopic techniques such as XRD, FT‐IR, SEM, ICP, BET and TEM its catalytic activity was investigated in the oxidative coupling of benzyl alcohol, benzaldhyde, benzoic acid, styrene and phenyl acetylene with N,N‐dialkylformamides for the preparation of N,N‐dimethylformamides. Different derivatives of tertiary amides were synthesized in moderate to good yields in the presence of just ~0.28 mol% of this catalytic system. Reusability of the synthesized catalysts was examined and catalysts were reusable for 8 times without significant decrease in optimized conditions.  相似文献   
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The photochemical reactions of the title complexes were studied in air-free benzene solution. In both cases photolysis leads to the production of complexes of the formula (η5-C5H5)M(PPh3)2. Both reactions are the result of the initial loss of a methyl radical from the excited state. The primary photoproduct, (η5-C5H5)MPPh3 (M=CO, Ni), then scavenges neutral ligands from the solution to yield, in the case of PPh3, (η5-C5H5)M(PPh3)2. In the absence of uncoordinated ligand in the reaction solution, the cobalt derivative reacts with the starting material to yield (η5-C5H5)Co(PPh3)2, a methyl radical and (η5-C5H5)Co(solvent)n.  相似文献   
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A quantitative structure–mobility relationship (QSMR) is proposed to estimate the electrophoretic mobility of diverse sets of analyses in capillary zone electrophoresis using Abraham solvation parameters of analyses, such as the excess molar refraction, polarizability, hydrogen bond acidity, basicity, and molar volume. QSMR was developed for prediction the electrophoretic mobility of 231 organic acids using the solvation parameters calculated by Abraham. Multiple linear regression (MLR) as a linear model and artificial neural network (ANN) methods were used to evaluate the nonlinear behavior of the involved parameters. The prediction results are obtained by nonlinear model, ANN, seem to be superior over MLR and were in good agreement with experimental data. In the proposed ANN–QSMR model, the overall mean percentage deviation values were 5.6, 5.4, and 5.3% and the coefficients of determinations (R2) were 0.84, 0.84, and 0.84 for training, test, and verification set, respectively. To investigate the robustness of the model, cross-validation methods have been established, i.e., leave-one-out and leave-N-out (N?=?5 and 10) and model is showed good predictive ability against data variation in cross-validation process. This model is not only able to accurately predict the migration order of a diverse set of organic acids but also model finds that solvation parameters are responsible in separation mechanism.  相似文献   
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We present a novel application of independent component analysis (ICA), an exploratory data analysis technique, to two-dimensional electrophoresis (2-DE) gels, which have been used to analyze differentially expressed proteins across groups. Unlike currently used pixel-wise statistical tests, ICA is a data-driven approach that utilizes the information contained in the entire gel data. We also apply ICA on wavelet-transformed 2-DE gels to address the high dimensionality and noise problems typically found in 2-DE gels. Also, we use an analysis-of-variance (ANOVA) approach as a benchmark for comparison. Using simulated data, we show that ICA detects the group differences accurately in both the spatial and wavelet domains. We also apply these techniques to real 2-DE gels. ICA proves to be much faster than ANOVA, and unlike ANOVA it does not depend on the selection of a threshold. Application of principal component analysis reduces the dimensionality and tends to improve the performance by reducing the noise.  相似文献   
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In the oxidative process of the supersilanide anion [SitBu3]?, radical species are generated. The continuous wave (cw)‐EPR spectrum of the reaction solution of Na[SitBu3] with O2 revealed a signal, which could be characterized as disupersilylperoxo radical anion [tBu3SiOOSitBu3]?? affected by sodium ions though ion‐pair formation. A mechanism is suggested for the oxidative process of supersilanide, which in a further step can be helpful in a better understanding of the oxidation process of isoelectronic phosphanes.  相似文献   
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In this paper the fractional sub-equation method is used to construct exact solutions of the fractional generalized reaction Duffing model and nonlinear fractional Sharma-Tasso-Olver equation.The fractional derivative is described in the Jumarie’s modified Riemann-Liouville sense. Two illustrative examples are given, showing the accuracy and convenience of the method.  相似文献   
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This paper presents a novel approach for generating structured light using a diffractive beam-shaping element that can generate multiple beams with distinct spatial structures in the focal plane. The element is constructed by restructuring a spiral zone plate with fork gratings, providing a tunable and controllable means for generating structured light. The element can create linear and 2D arrays of various structured beams, including vortices with adjustable charge and vorticity, petallike beams, and ring-lattice structures. To control the generation of these beams, it introduces several parameters of the fork gratings, enabling tailoring of the beam properties to specific applications. The proposed approach involves significant mathematical analysis, including the derivation of complex equations and expressions to understand the behavior of the proposed element and its impact on the generated beams. It conducts simulations and experiments to validate the mathematical analysis and demonstrate the feasibility of the proposed approach.  相似文献   
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One of the functions of Human Serum Albumin (HSA) is binding and transport of fatty acids. This ability could be altered by the presence of several blood components such as toxins or peptides – which in turn alters the functionality of the protein. We aim at characterizing HSA and its fatty acid binding in native serum environment. Native ligand binding and deviations from normal function can be monitored by electron paramagnetic resonance (EPR) spectroscopy using spin labeled fatty acids (FAs). Blood serum from healthy individuals is used to examine healthy HSA in its natural physiological conditions at different loading ratios of protein to FAs. Among the EPR spectroscopic parameters (like hyperfine coupling, line shape, rotational correlation time and population of different binding sites) the rotational correlation time is found to differ significantly between binding sites of the protein, especially at loading ratios of four FAs per HSA. Although differences are observed between individual samples, a general trend regarding the dynamics of healthy HSA at different loading ratios could be obtained and compared to a reference of purified commercially available HSA in buffer.  相似文献   
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