全文获取类型
收费全文 | 106篇 |
免费 | 1篇 |
专业分类
化学 | 41篇 |
晶体学 | 1篇 |
力学 | 3篇 |
数学 | 11篇 |
物理学 | 51篇 |
出版年
2022年 | 1篇 |
2021年 | 2篇 |
2020年 | 1篇 |
2018年 | 3篇 |
2017年 | 3篇 |
2016年 | 2篇 |
2015年 | 2篇 |
2014年 | 6篇 |
2013年 | 10篇 |
2012年 | 5篇 |
2011年 | 5篇 |
2010年 | 3篇 |
2009年 | 4篇 |
2008年 | 2篇 |
2007年 | 1篇 |
2006年 | 2篇 |
2005年 | 2篇 |
2003年 | 1篇 |
2002年 | 4篇 |
2001年 | 2篇 |
2000年 | 1篇 |
1997年 | 1篇 |
1996年 | 3篇 |
1995年 | 1篇 |
1992年 | 3篇 |
1989年 | 1篇 |
1987年 | 2篇 |
1986年 | 4篇 |
1985年 | 7篇 |
1983年 | 1篇 |
1980年 | 2篇 |
1979年 | 1篇 |
1977年 | 3篇 |
1975年 | 3篇 |
1974年 | 4篇 |
1972年 | 1篇 |
1970年 | 1篇 |
1928年 | 1篇 |
1903年 | 1篇 |
1870年 | 1篇 |
1868年 | 1篇 |
1858年 | 3篇 |
排序方式: 共有107条查询结果,搜索用时 31 毫秒
31.
Fernandez E Ford WT Qi N Read AL Smith JG Camporesi T De Sangro R Marini A Peruzzi I Piccolo M Ronga F Blume HT Hurst RB Venuti JP Wald HB Weinstein R Band HR Gettner MW Goderre GP Meyer OA Moromisato JH Polvado RO Shambroom WD Sleeman JC von Goeler E Ash WW Chadwick GB Clearwater SH Coombes RW Kaye HS Lau KH Leedy RE Lynch HL Messner RL Moss LJ Muller F Nelson HN Ritson DM Rosenberg LJ Wiser DE Zdarko RW Groom DE Lee HY Delfino MC Heltsley BK Johnson JR Lavine TL Maruyama T Prepost R 《Physical review letters》1985,54(11):1118-1121
32.
33.
Electrochemical Oxidation of the Antiretroviral Drug Nelfinavir on Modified Screen‐printed Electrodes
下载免费PDF全文
![点击此处可从《Electroanalysis》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Laura Asturias‐Arribas Mario Raúl Delfino M. Asunción Alonso‐Lomillo Olga Domínguez‐Renedo M. Julia Arcos‐Martínez 《Electroanalysis》2016,28(9):2081-2086
This paper describes the voltammetric study of the electrochemical oxidation of the antiretroviral drug Nelfinavir using a screen‐printed sensor modified with carbon nanotubes. The performance of the sensor in the determination of the drug was characterized in terms of precision (RSD 5.05 %, n=5) and capability of detection (10.99±0.87 μM for α=β=0.05, n=5) under optimized voltammetric conditions of pH, accumulation time and potential, in the calibration range from 10 to 150 μM of NFV. In order to check the viability of the device, the determination of the analyte in pharmaceutical and biological samples was carried out and its performance was also validated comparing it with HPLC. 相似文献
34.
Clusters and droplets of positive spins in the two-dimensional Ising model percolate at the Curie temperature in absence of external field. The percolative exponents coincide with the magnetic ones for droplets but not for clusters. We use integrable field theory to determine amplitude ratios which characterize the approach to criticality within these two universality classes of percolative critical behavior. 相似文献
35.
Adriana F. Ibaez Graciela Y. Moltrasio Iglesias Jos M. Delfino 《Journal of heterocyclic chemistry》1996,33(2):265-270
Ring and nitrogen inversion account for the conformational equilibria of 3-phenyl-1, 2,3, 4-tetrahydroiso-quinolines. In order to quantitate the relative contribution of each conformer to the equilibrium, we undertook a molecular mechanics study on several substituted 3-phenyl-1, 2, 3, 4-tetrahydroisoquinolines. Predictions from calculations were checked against cmr chemical shift data. No boat conformation contributed significantly to the equilibrium. A general result of our calculations is that in all cases the 3-phenyl group in the equatorial position is strongly favored (by at least 2.50 kcal/mole). For 3-phenyl-1, 2, 3, 4-tetrahydroisoquinolines without substitution at nitrogen, N-H in equatorial position is preferred over the axial conformer, although the energy difference between both is always small (0.30–1.10 kcal/mole). For the cis-1,3-disubstituted compounds the le'3e conformers are the only species present (at least 99.8%). The calculated energy differences between the la′3a conformer and the le′3e conformer are always large (3.80–6.10 kcal/mole for the NHe conformers and 3.60–3.80 kcal/mole for the NHa conformers). The lack of a γ1a upfield shift at C3 also points to the preference for the pseudoequatorial-equatorial conformer. For N-methyl-3-phenyl-1,2,3,4-tetrahydroisoquinoline a preference for the NMe group in the equatorial position is predicted (0.60–2.00 kcal/mole). The small downfield shift at C4 (γNa = 0.5 ppm) is consistent with the equatorial NMe preference. For the cis-1,2,3-trisubstituted compounds no significant γ1a effect at C3 (γ1a = -0.2 and 1.0 ppm) or γNa effect at C4 (γNa = 0.1 and 0.4 ppm) is observed. For these compounds, deformations due to steric congestion are evidenced by the deviation from the values of the C4a-C8a-Cl-N and C4a-C4-C3-N torsional angles, as compared to less crowded 3-phenyl-1,2,3,4-tetrahydroisoquinolines. Here the heterocyclic ring adopts a distorted half-chair conformation. 相似文献
36.
A study of the crystallographic, optical, and thermochemical properties of hydrazonium tartrate and deuterated hydrazonium tartrate enantiomers is described. Crystals of the enantiomers are orthorhombic with a tetramolecular cell. The space group is P212121 with the lattice parameters a0 = 7.640 ± 0.002 Å, b0 = 13.441 ± 0.003 Å, and c0 = 7.029 ± 0.002 Å. No change in lattice parameters is observed on deuteration. Optical second harmonic powder analysis shows the crystals to be phase matchable at 1.06 μm with d2ω = 11 d2ωα-SiO2. The optical nonlinearity being unaffected by deuterium substitution is attributed to the nonlinear electronic polarizability of the hydrogen bonds. Crystals are transparent from 239 nm to 1.61 μm. Deuteration shifts the long wavelength cutoff to 2.07 μm, without affecting the band edge. 相似文献
37.
We study the low-energy universality observed in three-body models through a scale-independent approach. From the already
estimated infinite number of three-body excited energy states, which happen in the limit when the energy of the subsystem
goes to zero, we are able to identify the lower energies of the helium trimers as possible examples of Thomas-Efimov states.
By considering this example, we illustrate the usefulness of a scaling function, which we have defined. The approach is applied
to bosonic systems of three identical particles, and also to the case where two kinds of particles are present.
Received June 30, 1999; revised July 27, 1999; accepted for publication August 29, 1999 相似文献
38.
F. Delfino R. Procopio M. Rossi 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,25(1):31-38
The evaluation of the total force of magnetic origin acting upon a body in a stationary magnetic field is often carried out
using the so-called magnetic energy (or co-energy) method, which is based on the derivation of the magnetic energy (or co-energy) with respect to a virtual rigid displacement
of the considered body. The application of this method is usually justified by resorting to the energy conservation principle,
written in terms both of electrical and of mechanical quantities. In this paper we shall re-examine the whole matter in the
context of classical thermodynamics, in order to obtain a more comprehensive and general proof of the validity of the energy
(or co-energy) approach and to point out its limitations. Two typical configurations will be discussed; in the first one,
the field sources are represented by conducting bodies carrying free currents, whereas in the second one a permanent magnet
creates the driving field. All magnetic materials are assumed to be non-hysteretic and permanent magnets are represented by
means of the well-known linear model in the second quadrant of the (B,H) plane.
Received 25 July 2001 and Received in final form 5 November 2001 相似文献
39.
The stability threshold for an Efimov state is determined as a function of the physical scales of the system. Light exotic
nuclei and triatomic molecules are investigated. Scaling, universality, and renormalization-group invariance properties are
discussed in this context.
Received October 25, 2001; accepted for publication November 12, 2001 相似文献
40.
M. Delfino G.M. Loiacono W.A. Smith A. Shaulov Y.H. Tsuo M.I. Bell 《Journal of solid state chemistry》1980,31(1):131-134
Measurements of the thermal and dielectric properties of single crystals of the double sulfates LiKSO4 and LiCsSO4 are reported. Uncertainty in the determination of the space group of LiCsSO4 is resolved on the basis of optical second harmonic generation and pyroelectric measurements; the correct space group is Pcmn. Measurements of the pyroelectric coefficient, dielectric constant, and specific heat of LiKSO4 permit an assessment of the suitability of this material for use in pyroelectric detectors. 相似文献