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Traumatic brain injury (TBI) is one of the commonest causes of morbidity and mortality in the developed countries with posttraumatic epilepsy and functional disability being its major sequelae. The purpose of this study was to test the hypothesis whether the normal appearing adjacent gray and white matter regions on T2 and T1 weighted magnetization transfer (MT) weighted images show any abnormality on quantitative imaging in patients with TBI. A total of 51 patients with TBI and 10 normal subjects were included in this study. There were significant differences in T2 and MT ratio values of T2 weighted and T1 weighted MT normal appearing gray matter regions adjacent to focal image abnormality compared to normal gray matter regions in the normal individuals as corresponding contralateral regions of the TBI patient's group (p < 0.05). However the adjoining normal appearing white matter quantitative values did not show any significant change compared to the corresponding contralateral normal white matter values. We conclude that quantitative T2 and MT ratio values provide additional abnormality in patients with TBI that is not discernable on conventional T2 weighted and T1 weighted MT imaging especially in gray matter. This additional information may be of value in overall management of these patients with TBI.  相似文献   
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Affinity capillary electrophoretic (ACE) study has proved the selectivity of hexaarylbenzene-based polyaromatic receptor (R) for K+ ion over Na+ ion. The apparent binding constants of the R complexes with K+ and Na+ ions were determined from the dependence of effective electrophoretic mobility of R on the concentration of the above alkali metal ions in the background electrolyte using a non-linear regression analysis. The apparent binding constants (Kb) of the K-R+ and Na–R+ complexes in methanolic medium were evaluated as log Kb = 3.20 ± 0.22 for the K–R+ complex, and log Kb??0.7 for the Na–R+ complex.  相似文献   
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[structure: see text]. Synthesis of a pair of rotamers (9u/9s) of a hexaarylbenzene derivative containing six (cofacially arranged) electroactive 2,5-dimethoxytolyl groups is described. The toroidal electronic stabilization due to the circular arrangement of aryl groups in 9u/9s leads to the observation of multiple (reversible) oxidation waves and lowering of their E(ox1) by approximately 250 mV relative to model compounds. The binding of K+ to symmetrical rotamer 9s was monitored by an electrochemical method and further confirmed by X-ray crystallography.  相似文献   
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A decoupled input–output linearizing controller (DIOLC) was designed as an alternative advanced control strategy for controlling bioprocesses. Simulation studies of its implementation were carried out to control ethanol and biomass production in Saccharomyces cerevisiae and its performance was compared to that of a proportional–integral–derivative (PID) controller with parameters tuned according to a linear schedule. The overall performance of the DIOLC was better in the test experiments requiring the controllers to respond accurately to simultaneous changes in the trajectories of the substrate and dissolved oxygen concentration. It also exhibited better performance in perturbation experiments of the most significant parameters q S,max, q O2,max, and k s , determined through a statistical design of experiments involving 730 simulations. DIOLC exhibited a superior ability of constraining the process when implemented in extreme metabolic regimes of high oxygen demand for maximizing biomass concentration and low oxygen demand for maximizing ethanol concentration.  相似文献   
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Plasma Chemistry and Plasma Processing - The present study has been carried to investigate the interaction and effect of plasma activated water (PAW) on pea seeds. PAW is produced with the...  相似文献   
18.
As part of a continuing study of cardiac g1ycos1des,1,2 stereoselective syntheses of the four possible glucosides of digitoxigenin were developed via the thermodynamically produced tetra-O-benzyl-D- and L-glucosyl α-trichloroacetaimidates 2α and 11α, and the kinetically produced β-trichloroacetaimidates 2β and 11β. A 58%:19% isolated yield ratio of α-D and β-D benzyl protected glycosides 6 and 3 could be obtained in 30 minutes reaction at ?10°. Halide ion catalysis with a 2:1 excess of tetra-O-benzyl-α-D-glucopyranosyl bromide for 14 days in methylene chloride at room temperature gave a 39%:11% ratio of 6 and 3, along with 43% of recovered digitoxigenin. Debenzylation of the D-glucosides required milder conditions (20% Pd/C, atmospheric pressure, 45 min-1 hr) than the L-glucosides (40% Pd/C, 2 hr) but yields were typically 80% for both groups.  相似文献   
19.
A unique peptide based search algorithm for identification of protein mixture using PMF is proposed. The proposed search algorithm utilizes binary search and heapsort programs to generate frequency chart depicting the unique peptides corresponding to all proteins in a proteome. The use of binary search program significantly reduces the time for frequency chart preparation to ~2 s for a proteome comprising ~23 000 proteins. The algorithm was applied to a three‐protein mixture identification, host cell protein (HCP) analysis, and a simulation‐generated data set. It was found that the algorithm could identify at least one unique peptide of a protein even in the presence of fourfold higher concentration of another protein. In addition, two HCPs that are known to be difficult to remove were missed by MS/MS approach and were exclusively identified using the presented algorithm. Thus, the proposed algorithm when used along with standard proteomic approaches present avenues for enhanced protein identification efficiency, particularly for applications such as HCP analysis in biopharmaceutical research, where identification of low‐abundance proteins are generally not achieved due to dynamic range limitations between the target product and HCPs.  相似文献   
20.
Calix[4]arene‐based molecules hold great promise as candidate sensors and storage materials for nitric oxide (NO), owing to their unprecedented binding affinity for NO. However, the structure of calix[4]arene is complicated by the availability of four possible conformers: 1,3‐alternate, 1,2‐alternate, cone, and partial cone (paco). Whilst complexes of NO with several of these conformers have previously been established, the 1,2‐alternate conformer complex, that is, [1,2‐alter ? NO]+, has not been previously reported. Herein, we determine the crystal structure of the NO complex with the 1,2‐alternate conformer for the first time. In addition, we have also found that the 1,2‐alternate and 1,3‐alternate conformers can combine with two NO molecules to form stable bis(nitric oxide) complexes. These new complexes, which exhibit remarkable binding capacity for the construction of NO‐storage molecules, were characterized by using X‐ray crystallography and NMR, IR, and UV/Vis spectroscopy. These findings will extend our understanding of the interactions between nitric oxide and cofacially and non‐cofacially arrayed aromatic rings, and we expect them to aid in the design and development of new supramolecular sensors and storage materials for NO with high capacity and efficacy.  相似文献   
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