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71.
In this paper, we revisit the origins of Emile Borel's developing interest in probability around 1905. This resulted from new findings in his research on continued fraction, but it also cannot be separated from the discovery of new applications for the mathematics of randomness (such as biology or economics) and of their importance as a life‐changing tool for the citizen. In particular, we underline the role of a paper published by Vito Volterra in Borel's Revue du Mois.  相似文献   
72.
Monocyte chemoattractant proteins (MCPs) are cytokines that direct immune cells bearing appropriate receptors to sites of inflammation or injury and are therefore attractive therapeutic targets for inhibitory molecules. 11K2 is a blocking mouse monoclonal antibody active against several human and murine MCPs. A 2.5 A structure of the Fab fragment of this antibody in complex with human MCP-1 has been solved. The Fab blocks CCR2 receptor binding to MCP-1 through an adjacent but distinct binding site. The orientation of the Fab indicates that a single MCP-1 dimer will bind two 11K2 antibodies. Several key residues on the antibody and on human MCPs were predicted to be involved in antibody selectivity. Mutational analysis of these residues confirms their involvement in the antibody-chemokine interaction. In addition to mutations that decreased or disrupted binding, one antibody mutation resulted in a 70-fold increase in affinity for human MCP-2. A key residue missing in human MCP-3, a chemokine not recognized by the antibody, was identified and engineering the preferred residue into the chemokine conferred binding to the antibody.  相似文献   
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Objective

The effects of aging, magnetic field and the voxel localization on measured concentrations of citrate (Cit), creatine (Cr), cholines (Cho) and polyamines (PA) in a healthy prostate were evaluated.

Materials and methods

36 examinations at both 1.5T and 3T imagers of 52 healthy subjects aged 19–71 years were performed with PRESS 3D-CSI sequences (TE = 120 and 145 ms). Concentrations in laboratory units and their ratios to citrate were calculated using the LCModel technique. Absolute concentrations were also obtained after the application of correction coefficients. Statistical analysis was performed using a robust linear mixed effects model.

Results

Significant effects of aging, the magnetic field strength and the voxel position in central (CZ) or peripheral (PZ) zones on all measured metabolites were found. The concentrations (mmol/kg wet tissue) including prediction intervals in a range of 20–70 years were found: Cit: 7.9–17.2; Cho: 1.4–1.7; Cr: 2.8-2.5; PA (as spermine): 0.6–2.1 at 3T in CZ. In PZ, the concentrations were higher by about 10 % as compared to CZ.

Conclusion

Increasing citrate and spermine concentrations with age are significant and correlate well with a recently described increase of zinc in the prostate. These findings should be considered in decision-making if the values obtained from a subject are in the range of control values.
  相似文献   
76.
DNA methylation is the most studied epigenetic mechanism that regulates gene expression, and it can serve as a useful biomarker of prior environmental exposure and future health outcomes. This study focused on DNA methylation profiles in a human cohort, comprising 125 nonsmoking city policemen (sampled twice), living and working in three localities (Prague, Ostrava and Ceske Budejovice) of the Czech Republic, who spent the majority of their working time outdoors. The main characterization of the localities, differing by major sources of air pollution, was defined by the stationary air pollution monitoring of PM2.5, B[a]P and NO2. DNA methylation was analyzed by a genome-wide microarray method. No season-specific DNA methylation pattern was discovered; however, we identified 13,643 differentially methylated CpG loci (DML) for a comparison between the Prague and Ostrava groups. The most significant DML was cg10123377 (log2FC = −1.92, p = 8.30 × 10−4) and loci annotated to RPTOR (total 20 CpG loci). We also found two hypomethylated loci annotated to the DNA repair gene XRCC5. Groups of DML annotated to the same gene were linked to diabetes mellitus (KCNQ1), respiratory diseases (PTPRN2), the dopaminergic system of the brain and neurodegenerative diseases (NR4A2). The most significant possibly affected pathway was Axon guidance, with 86 potentially deregulated genes near DML. The cluster of gene sets that could be affected by DNA methylation in the Ostrava groups mainly includes the neuronal functions and biological processes of cell junctions and adhesion assembly. The study demonstrates that the differences in the type of air pollution between localities can affect a unique change in DNA methylation profiles across the human genome.  相似文献   
77.
SnCl4 reacts with [1,2‐(N,N‐dimethylaminomethyl) ferrocenyl]lithium (FcNLi) under formation of the organo tin compounds of the four valued tin (FcN)n SnCl 4‐n [n = 1( 1 ), 2( 2 ), 3( 3 ), 4( 4 )]. The heterobimetallic chelate complex bis[1,2‐(N,N‐dimethylaminomethyl)ferrocenyl]tin(II) (FcN)2 Sn ( 5 ) is formed at the reaction of SnCl2 with two equivalents of FcNLi. The heterobimetallic tin compounds 1 — 5 were characterized by 1H NMR‐, 13C‐NMR and mass spectroscopy, single crystal x‐ray analyses ( 1,3,4,5 ), 57 Fe‐Moessbauer spectroscopy ( 1, 3, 4, 5 ), respectively cyclic voltammetry.  相似文献   
78.
The stress-induced B2–B19′ transformation in aged 51 at.% NiTi was investigated using in situ straining transmission electron microscopy (TEM). Increased applied strain along [1 1 0]B2 transforms B2 into plates containing B19′ variants that are related by a (1 1 0)B2 compound twin plane. This atypical twin plane is explained by relaxing the invariant plane constraint in the crystallographic theory of martensite (CTM) to an invariant line constraint. The relaxation is rationalized from the thin foil geometry. The relaxed CTM approach, coupled with conditions to maximize transformation strain along the loading axis and minimize elastic energy, predicts the observed twin interface, diffraction patterns, and interface with the B2 austenite. These results demonstrate subtleties in interpreting thin foil TEM results regarding martensitic transformations, and translating those results to bulk response.  相似文献   
79.
The thermal aging of a glass matrix composite reinforced by short carbon fibres as well as by ZrO2 particles (hybrid composite) was investigated at temperatures in the range 500–700 °C for exposure durations of 24 h in air. The mechanical properties of as-received and aged samples were evaluated at room temperature by using the three-point flexure chevron notch technique. The fracture toughness values of as-received specimens were in the range 2.6–6.4 MPa m1/2. Fracture toughness was affected by the thermal aging conditions. For thermal aging at temperatures <700 °C, degradation of fibre–matrix interfaces occurred and therefore the apparent fracture toughness and flaw tolerant resistance decreased. For the most severe ageing conditions tested (700 °C/24 h), fracture toughness values dropped to 0.4 MPa m1/2. Significant degradation of the material was detected for this aging condition, mainly characterised by porosity formation in the matrix as a result of softening of the glass and oxidation of the carbon fibres.  相似文献   
80.
The mechanical failure of one cell is sufficient to lead to the end of service of a solid oxide fuel cell (SOFC) stack. Therefore, there is growing interest in gaining knowledge on the mechanical properties of the cell materials for stress analysis.This study compiles available data from the literature on the mechanical properties of the most common materials used in intermediate-temperature anode-supported cells: nickel and yttria-stabilized zirconia (Ni–YSZ) anodes, YSZ electrolytes, yttria (YDC) or gadolinia-doped ceria (GDC) compatibility layers and lanthanum strontium manganite (LSM) or lanthanum strontium cobalt ferrite (LSCF) cathodes. The properties for the simulation of stresses, i.e. coefficient of thermal expansion (CTE), Young's modulus, Poisson's ratio, creep behaviour and strength are reported, with an emphasis on temperature and porosity dependence and the evolution upon aging or cycling when available. Measurements of our Ni(O)–YSZ anode material includes the CTE (oxidised and reduced state), Young's modulus and strength at room temperature (oxidised and reduced) and 1073 K (oxidised).  相似文献   
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