全文获取类型
收费全文 | 148篇 |
免费 | 0篇 |
专业分类
化学 | 106篇 |
力学 | 6篇 |
数学 | 17篇 |
物理学 | 19篇 |
出版年
2023年 | 1篇 |
2022年 | 3篇 |
2021年 | 2篇 |
2020年 | 2篇 |
2019年 | 1篇 |
2018年 | 1篇 |
2015年 | 1篇 |
2014年 | 4篇 |
2013年 | 7篇 |
2012年 | 10篇 |
2011年 | 15篇 |
2010年 | 2篇 |
2009年 | 6篇 |
2008年 | 4篇 |
2007年 | 6篇 |
2006年 | 9篇 |
2005年 | 19篇 |
2004年 | 10篇 |
2003年 | 4篇 |
2002年 | 6篇 |
2001年 | 1篇 |
2000年 | 1篇 |
1999年 | 3篇 |
1998年 | 5篇 |
1997年 | 3篇 |
1996年 | 3篇 |
1994年 | 3篇 |
1991年 | 2篇 |
1990年 | 1篇 |
1989年 | 2篇 |
1988年 | 2篇 |
1985年 | 1篇 |
1982年 | 2篇 |
1978年 | 1篇 |
1977年 | 2篇 |
1976年 | 2篇 |
1971年 | 1篇 |
排序方式: 共有148条查询结果,搜索用时 0 毫秒
1.
Masson JF Battaglia TM Davidson MJ Kim YC Prakash AM Beaudoin S Booksh KS 《Talanta》2005,67(5):918-925
The elimination or minimization of non-specific protein adsorption from serum is critical for the use of surface plasmon resonance (SPR) sensors for in vitro and in vivo analysis of complex biological solutions. The ultimate goals in this application are to minimize non-specific adsorption of protein and to maximize analyte signal. A reduction of the non-specific protein adsorption from serum of up to 73% compared to carboxymethylated-dextran 500 kDa (CM-dextran) was achieved following a survey of eight biocompatible polymers and 10 molecular weights of CM-dextran. These coatings minimize non-specific adsorption on the sensor while also serving as immobilization matrices for antibody fixation to the probes. Polymers including polysaccharides: CM-dextrans, CM-hyaluronic acid, hyaluronic acid, and alginic acid were investigated. Humic acid, polylactic acid, polyacrylic acid, orthopyridyldisuldfide–polyethyleneglycol–N-hydroxysuccinimide (OPSS–PEG–NHS), and a synthesized polymer; polymethacrylic-acid-co-vinyl-acetate (PMAVA) were also used. The non-specific protein adsorption reduction was measured over a 14 day period at 0 °C for each polymer. Calibration curves using some of these polymers were constructed to show the performance and low detection limit possibilities of these new antibody supports. For many of the polymers, this is the first demonstration of employment as an antibody support for an optical or surface active sensor. CM-dextran is the polymer offering the largest signal for the antigen detection. However, the biocompatible polymers demonstrate a greater stability to non-specific binding in serum. These biocompatible polymers offer different alternatives for CM-dextran. 相似文献
2.
Jean-Claude Berthet Jean-Francois Le Mar chal Michel Ephritikhine 《Journal of organometallic chemistry》1994,480(1-2):155-161
The monocyclooctatetraene uranium complex [U(COT)(I)2(THF)2] (COT=η-C8H8; THF=tetrahydrofuran), isolated from the reaction of bis(cyclooctatetraene)uranium with iodine, is a precursor for the synthesis of the alkyl derivatives [U(COT)(CH2Ph)2i (HMPA) 2], [U(COT)(CH2SiMe3)2(HMPA)] (HMPA=hexamethyl phosphorous triamide) and [U(COT)CH2SiMe3)3] [Li(THF)3] and of the mixed-ring compounds [U(COT)(η-C5R5)(I)] (R=H or Me). The last were used to prepare the amide and alkyl complexes [U(COT)(η-C5H5)(N{SiMe3}2)] and [U(COT)(η-C5Me5)(CH2SiMe3)]. 相似文献
3.
Charly Mayeux Peeter Burk Jean-Francois Gal Ivari Kaljurand Ilmar Koppel Ivo Leito Lauri Sikk 《Journal of the American Society for Mass Spectrometry》2014,25(11):1962-1973
According to high level calculations, the upper part of the previously published FT-ICR lithium cation basicity (LiCB at 373 K) scale appeared to be biased by a systematic downward shift. The purpose of this work was to determine the source of this systematic difference. New experimental LiCB values at 373 K have been measured for 31 ligands by proton-transfer equilibrium techniques, ranging from tetrahydrofuran (137.2 kJ mol?1) to 1,2-dimethoxyethane (202.7 kJ mol?1). The relative basicities (ΔLiCB) were included in a single self-consistent ladder anchored to the absolute LiCB value of pyridine (146.7 kJ mol?1). This new LiCB scale exhibits a good agreement with theoretical values obtained at G2(MP2) level. By means of kinetic modeling, it was also shown that equilibrium measurements can be performed in spite of the formation of Li+ bound dimers. The key feature for achieving accurate equilibrium measurements is the ion trapping time. The potential causes of discrepancies between the new data and previous experimental measurements were analyzed. It was concluded that the disagreement essentially finds its origin in the estimation of temperature and the calibration of Cook’s kinetic method. Graphical Abstract
? 相似文献
4.
The first experimental studies of Os(-) reveal the presence of two very strong resonances. One state is a narrow shape resonance lying only 3.52(12) meV above the ground state detachment threshold, while the other is bound by 11.48(12) meV. Convincing evidence that these states have odd parity is presented, making Os(-) the only known atomic negative ion with bound states of opposite parity. Additionally, the binding energies for the Os(-) ground state ((4)F(e)(9/2)) and first excited state ((4)F(e)(7/2)) are measured to be 1.077 80(12) eV and 0.553(3) eV, respectively. 相似文献
5.
We compute the 2-rank of the wild kernel WK2(F) of a number field by constructing a 2-class group ad hoc. The main result generalizes in the more intricate case the canonical isomorphism established for odd primes under the assumption in a previous article (cf. (Acta. Arith. 67 (1994) 335; Math. Z. 238 (2001) 335)). It involves a criterium of triviality for the 2-part of the wild kernel of Galois number fields and, in the particular case of quadratic fields, it leads to a logarithmic interpretation of the diophantine conditions obtained by other authors. 相似文献
6.
Ismaili L Truong TT André C Thomassin M Mozer JL Robert JF Xicluna A Refouvelet B Millet J Nicod L Guillaume YC 《Journal of AOAC International》2003,86(2):222-228
The mechanism of the binding of D,L dansyl amino acids to teicoplanin was investigated. Na+ was used as an indicator of the interactions between the solutes and teicoplanin. The number (n) of sodium ions, Na+, excluded from the solute-teicoplanin interface when analyte transfer occurred was determined. A thermodynamic study and enthalpy-entropy compensation were performed to further explore the interaction mechanism. From these results, it was shown that teicoplanin was balanced between 2 conformational states characterized by distinct enantioselective properties. This approach indicates that liquid chromatography (LC) is a useful tool to extract physicochemical and molecular information from retention data. Thus, LC can be used as a complementary technique with the conventional techniques of molecular interaction analysis. 相似文献
7.
Bolduc OR Correia-Ledo D Masson JF 《Langmuir : the ACS journal of surfaces and colloids》2012,28(1):22-26
The application of a potential to deposit a monolayer of 3-mercaptopropionic acid-histidinyl-histidinyl-histidinyl-aspartyl-aspartyl (3-MPA-HHHDD-OH) controls the density and molecular structure of the peptide monolayer, which results in different wettabilities of the surface, surface density, orientation of the molecule (extended or bent), and nonspecific adsorption of serum proteins. 3-MPA-HHHDD-OH must be deposited at 200 mV to maintain an extended configuration, which promoted low biofouling properties. 相似文献
8.
9.
A model was developed to simulate permeability decrease induced by hydrodynamic effects when injecting a fluid in a reservoir with respect to particle release and capture mechanisms and the parameters of the fluid–rock system. The kinetics of particle release and capture were integrated after computing the initial permeability of the porous medium with a square lattice of a two–dimensional network model. The rate of particle release is related to the difference between a microscopic velocity of the fluid and a critical velocity. The permeability decrease shows a direct link to the reduction of pore throat radii by three mechanisms of particle capture: straining and particle accumulation through direct interception or diffusion. Comparison between the simulations and the experimental results shows that the model reproduces the physics of the permeability decrease phenomenon, although the values are overestimated. The difference between the two sets of results can be explained by the fact that the simulations are realized at constant pressure whereas the experiments are realized at constant flow rate, and that re–entrainment of the trapped particles was not taken into account in the model. 相似文献
10.
Jean-Francois Bisson Hideki Yagi Takakimi Yanagitani Alexander Kaminskii Yuri N. Barabanenkov Ken-Ichi Ueda 《Optical Review》2007,14(1):1-13
Grain boundaries play a key role in determining several key properties of polycrystalline laser ceramics. Heat transfer measurements
at low temperature constitute a good tool to probe grain boundaries. We review the results of heat transfer measurements in
polycrystalline Y3Al5O12 garnets as well as Y2O3 and Lu2O3 sesquioxide materials obtained by self-energy-driven sintering of nano-particles. The average phonon mean free path in Y3Al5O12 was found to be significantly larger than the average grain size and to scale with temperature as T
−2 at low temperature. Existing models describing the interaction between phonons and grain boundaries are reviewed. Correct
temperature dependence of the mean free path and order of magnitude of scattering rates were found by assuming the existence
of a grain boundary layer having acoustic properties different from those of the bulk. A different temperature dependence
of phonon mean free path was found for the sesquioxides and was ascribed to the stronger elastic anisotropy of these materials.
The thermal resistance associated to the grain boundaries of laser ceramics was found to be lower than in other dense polycrystalline
ceramic materials reported in the literature. 相似文献