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1.
Measurements of the polarization parameter of the reactions π?p → π0n and π?p → ηn at 4.90 and 7.85 GeV/c and for a squared four-momentum transfer ?t ranging from 0.1 to 2.0 (GeV/c)2 have been achieved by using a butanol polarized proton target and detecting only the two γ's from the neutral meson decay. The background due to events involving bound protons has been separately measured and subtracted out. A large positive polarization has been found for the reaction π?p → π0n. It is consistent with other pion-nucleon scattering data connected by isospin conservation. The polarization for the reaction π?p → ηn is not significantly different from zero within the large experimental errors.  相似文献   
2.

Aim

So far different approaches have been used to quantify late gadolinium enhancement (LGE) in patients with hypertrophic cardiomyopathy (HCM), but there is no general consensus on the gold standard, since histological data are scarce. The aim of our study was to investigate whether the determination of LGE in patients with HCM using a semiquantitative score based on the 17-segment model is feasible and has comparable accuracy to manual planimetry.

Methods

Forty-two patients with HCM underwent LGE cardiovascular magnetic resonance imaging. Determination of LGE by planimetry based on visual assessment was used as reference standard. Then the extent of LGE was assessed using a semiquantitative score based on the standard left ventricular 17-segment model. Each segment was scored for the distribution of LGE. The resulting summed score expressed as percentage of the maximum possible score was thereafter compared with the manual planimetric evaluation of LGE, expressed as a percentage of the left ventricular myocardial area.

Results

In 28 patients (66%), LGE was present. There was a good correlation between the semiquantitative score and the planimetric approach (r=0.89; y=0.819x+2.45; standard error of estimation=2.327; P<.0001). Additionally, the Bland–Altmann plot showed a high concordance between the two approaches (mean of the difference +1.7%). The inter- and intraobserver limits of agreement and the coefficients of repeatability based on measurements with the semiquantitative score of the extent of LGE were superior to planimetric measurements. Besides, the time requirement for the LGE determination using the semiquantitative score was found to be significantly reduced compared to manual planimetry (median 2 vs. 10 min).

Conclusions

Thus, a reliable global index of the size of the LGE is feasible and can easily be obtained from visual assessment with a semiquantitative score of the extent of the hyperenhancement.  相似文献   
3.
Energy-efficient indoors temperature and humidity control can be realised by using the reversible adsorption and desorption of water in porous materials. Stable microporous aluminium-based metal–organic frameworks (MOFs) present promising water sorption properties for this goal. The development of synthesis routes that make use of available and affordable building blocks and avoid the use of organic solvents is crucial to advance this field. In this work, two scalable synthesis routes under mild reaction conditions were developed for aluminium-based MOFs: (1) in aqueous solutions using a continuous-flow reactor and (2) through the vapour-assisted conversion of solid precursors. Fumaric acid, its methylated analogue mesaconic acid, as well as mixtures of the two were used as linkers to obtain polymorph materials with tuneable water sorption properties. The synthesis conditions determine the crystal structure and either the MIL-53 or MIL-68 type structure with square-grid or kagome-grid topology, respectively, is formed. Fine-tuning resulted in new MOF materials thus far inaccessible through conventional synthesis routes. Furthermore, by varying the linker ratio, the water sorption properties can be continuously adjusted while retaining the sigmoidal isotherm shape advantageous for heat transformation and room climatisation applications.  相似文献   
4.
5.
The dynamical pairfield susceptibility of gapless superconductors has been calculated using the theory of Gorkov and Eliashberg and improvements thereof. The result differs drastically from the usual Ginzburg-Landau theory and agrees qualitatively with recent experiments on the I–V characteristic of tunnel junctions with Al films.  相似文献   
6.
The asymmetry A = +?)+?) of the reaction γp↑↓ → π0p was measured at the Deutsches Elektronen Synchrotron DESY, Hamburg at a mean photon energy of 4.0 GeV in the four-momentum transfer range 0.2 (GeV/c)2 ? ?t ? 1.1 (GeV/c)2 in steps of approximately 0.08 (GeV/c)2. The π0-meson and the proton were detected in coincidence. The asymmetry is compatible with zero in the t-range 0.2 (GeV/c)2 ? ?t ? 0.4 (GeV/c)2 and negative in the t-range ? 0.5 (GeV/c)2.  相似文献   
7.
Cross sections for some electro- and photoinduced spallation reactions on27Al and51V have been measured in the energy region 130–580 MeV with the activation method. The cross sections per photon are compared to Monte-Carlo calculations based on a cascade-evaporation model. The electrodisintegration cross sections are compared to calculations based on the Dalitz formalism for virtual photon spectra.  相似文献   
8.
We present a unit commitment model which determines generator schedules, associated production and storage quantities, and spinning reserve requirements. Our model minimizes fixed costs, fuel costs, shortage costs, and emissions costs. A constraint set balances the load, imposes requirements on the way in which generators and storage devices operate, and tracks reserve requirements. We capture cost functions with piecewise-linear and (concave) nonlinear constructs. We strengthen the formulation via cut addition. We then describe an underestimation approach to obtain an initial feasible solution to our model. Finally, we constitute a Benders’ master problem from the scheduling variables and a subset of those variables associated with the nonlinear constructs; the subproblem contains the storage and reserve requirement quantities, and power from generators with convex (linear) emissions curves. We demonstrate that our strengthening techniques and Benders’ Decomposition approach solve our mixed integer, nonlinear version of the unit commitment model more quickly than standard global optimization algorithms. We present numerical results based on a subset of the Colorado power system that provide insights regarding storage, renewable generators, and emissions.  相似文献   
9.
Coincidence cross sections for the reactions 6Li(e, e′p) and 6Li(e, e′d) have been measured in the region of quasi-elastic scattering. Using incident electrons of 2.5 and 2.7 GeV, the four-momentum transfers to the proton were 6.6 fm?2, 10.0 fm?2 and 11.6 fm?2. The proton coincidence data agree with shell-model distributions assuming a Woods-Saxon potential and including short-range nucleon-nucleon correlations. The best fit to the deuteron coincidence data is obtained with a cluster wave function for the p-nucleons and a harmonic oscillator wave function for the s-nucleons taking into account the deuteron yield from the s-shell. The ratio of the deuteron cross section from 6Li divided by the elastic e-d scattering cross section depends only slightly on the four-momentum transfer and has a value of ≈ 2.  相似文献   
10.
Cross sections for some electro- and photoinduced spallation reactions on27Al and51V have been measured in the energy region 130–580 MeV with the activation method. The cross sections per photon are compared to Monte-Carlo calculations based on a cascade-evaporation model. The electrodisintegration cross sections are compared to calculations based on the Dalitz formalism for virtual photon spectra.  相似文献   
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