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91.
We propose the use of the third-order multiple regression equations in approximating an optical density ratio with an adaptive exponential function for measuring depth and thickness of a blood inclusion embedded in a skin tissue model. To ensure accuracy of the exponential approximation, we investigated numerically various relations of optical density ratios versus depth and thickness, on the basis of Monte Carlo simulations for a layered skin tissue model. The third-order multiple regression analysis based on the relations above was used to derive regression equations for the determination of depth and thickness. Experiments with skin tissue phantoms were used to assess this approach. 相似文献
92.
Takaaki Shirai Shunsuke Satou Morihiro Saito Jun Kuwano Hidenobu Shiroishi 《Solid State Ionics》2009,180(6-8):569-574
The proton conducting 0.9MO2·0.05In2O3·1.3P2O5 (MTi, Sn, Zr) electrolytes based on a core-shell structure were synthesized by a ball milling method. The core-shell type electrolytes showed the proton conductivities ranging from a higher value than those of Nafion membranes to 10? 5 Scm? 1 at intermediate temperatures of 150–200 °C, depending on the heat-treatment conditions. The samples with high conductivity were proved to adopt a core-shell structure by SEM observation, powder XRD analysis and 31P MAS-NMR measurements. 相似文献
93.
Nakata Y Honda Y Ninomiya S Seki T Aoki T Matsuo J 《Journal of mass spectrometry : JMS》2009,44(1):128-136
The importance of imaging mass spectrometry (MS) for visualizing the spatial distribution of molecular species in biological tissues and cells is growing. We have developed a new system for imaging MS using MeV ion beams, termed MeV-secondary ion mass spectrometry (MeV-SIMS) here, and demonstrated more than 1000-fold increase in molecular ion yield from a peptide sample (1154 Da), compared to keV ion irradiation. This significant enhancement of the molecular ion yield is attributed to electronic excitation induced in the near-surface region by the impact of high energy ions. In addition, the secondary ion efficiency for biologically important compounds (>1 kDa) increased to more than 10(10) cm(-2), demonstrating that the current technique could, in principle, achieve micrometer lateral resolution. In addition to MeV-SIMS, peptide compounds were also analyzed with cluster-SIMS and the results indicated that in the former method the molecular ion yields increased substantially compared to the latter. To assess the capability of MeV-SIMS to acquire heavy-ion images, we have prepared a micropatterned peptide surface and successfully obtained mass spectrometric imaging of the deprotonated peptides (m/z 1153) without any matrix enhancement. The results obtained in this study indicate that the MeV-SIMS technique can be a powerful tool for high-resolution imaging in the mass range from 100 to over 1000 Da. 相似文献
94.
A multi-charged particle model with local U(1)μ-τ to explain muon g–2, flavor physics,and possible collider signature 下载免费PDF全文
We consider a model with multi-charged particles, including vector-like fermions, and a charged scalar under a local \begin{document}$ U(1)_{\mu - \tau} $\end{document} ![]()
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symmetry. We search for an allowed parameter region explaining muon anomalous magnetic moment (muon \begin{document}$ g-2 $\end{document} ![]()
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) and \begin{document}$ b \to s \ell^+ \ell^- $\end{document} ![]()
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anomalies, satisfying constraints from the lepton flavor violations, Z boson decays, meson anti-meson mixing, and collider experiments. Via numerical analysis, we explore the typical size of the muon \begin{document}$ g-2 $\end{document} ![]()
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and Wilson coefficients to explain the \begin{document}$ b \to s \ell^+ \ell^- $\end{document} ![]()
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anomalies in our model when all other experimental constraints are satisfied. Subsequently, we discuss the collider physics of the multicharged vectorlike fermions, considering a number of benchmark points in the allowed parameter space. 相似文献
95.
Kim Seok-Jun Sakai Takaaki Oda Hiroyuki Okuyama Yuji Mizutani Yumi Hamagami Jun-Ichi Matsuka Maki Ishihara Tatsumi Matsumoto Hiroshige 《Journal of Solid State Electrochemistry》2012,16(11):3587-3592
Journal of Solid State Electrochemistry - The long-term stability in water was investigated for an inorganic proton conductor based on sulfated hydrous titania electrolyte in water electrolysis.... 相似文献
96.
Terao K Shimizu K Miyanishi N Shimamoto S Suzuki T Takao H Oohira F 《The Analyst》2012,137(9):2192-2198
We propose a novel surface plasmon resonance (SPR) sensor chip with a microfabricated slit array. The microslit excludes micrometre-size objects larger than its slit size from the SPR sensing area, so that it functions as an in situ filter. We demonstrated the sensing of microparticles of different diameters using the chip, and the results show a successful size-exclusion effect. As a demonstration of the biological application, we performed the detection of aggregation and disaggregation of biological particles using sugar-chain-immobilized gold nanoparticles as a test sample. 相似文献
97.
A main electromagnet optimized for electron paramagnetic resonance (EPR) measurements of rats by using a surface loop resonator with a loop diameter of 10?mm was designed. The fabricated main electromagnet was ca. 420?mm in diameter, ca. 240?mm in width, and ca. 60?kg in weight. When a static magnetic field of 25?mT was generated at the center of the main electromagnet, its deviation in a sphere space with a diameter of 10?mm was <0.02?mT. In this condition, the temperature elevation on the surface of the magnet was negligible for the measurement time assumed for in vivo study. Using this magnet, a bench-top type in vivo EPR spectrometer could be obtained, which made it possible to perform EPR measurements for estimating the renal reducing ability of a rat. 相似文献
98.
W Shimizu S Nakamura T Sato Y Murakami 《Langmuir : the ACS journal of surfaces and colloids》2012,28(33):12245-12255
Amorphous titanium dioxide (TiO(2)) thin films exhibiting high refractive indices (n ≈ 2.1) and high transparency were fabricated by spin-coating titanium oxide liquid precursors having a weakly branched polymeric structure. The precursor solution was prepared from titanium tetra-n-butoxide (TTBO) via the catalytic sol-gel process with hydrazine monohydrochloride used as a salt catalyst, which serves as a conjugate acid-base pair catalyst. Our unique catalytic sol-gel technique accelerated the overall polycondensation reaction of partially hydrolyzed alkoxides, which facilitated the formation of liner polymer-like titanium oxide aggregates having a low fractal dimension of ca. (5)/(3), known as a characteristic of the so-called "expanded polymer chain". Such linear polymeric features are essential to the production of highly dense amorphous TiO(2) thin films; mutual interpenetration of the linear polymeric aggregates avoided the creation of void space that is often generated by the densification of high-fractal-dimension (particle-like) aggregates produced in a conventional sol-gel process. The mesh size of the titanium oxide polymers can be tuned either by water concentration or the reaction time, and the smaller mesh size in the liquid precursor led to a higher n value of the solid thin film, thanks to its higher local electron density. The reaction that required no addition of organic ligand to stabilize titanium alkoxides was advantageous to overcoming issues from organic residues such as coloration. The dense amorphous film structure suppressed light scattering loss owing to its extremely smooth surface and the absence of inhomogeneous grains or particles. Furthermore, the fabrication can be accomplished at a low heating temperature of <80 °C. Indeed, we successfully obtained a transparent film with a high refractive index of n = 2.064 (at λ = 633 nm) on a low-heat-resistance plastic, poly(methyl methacrylate), at 60 °C. The result offers an efficient route to high-refractive-index amorphous TiO(2) films as well as base materials for a wider range of applications. 相似文献
99.
Kurinomaru T Tomita S Kudo S Ganguli S Nagasaki Y Shiraki K 《Langmuir : the ACS journal of surfaces and colloids》2012,28(9):4334-4338
The development of technology for on/off switching of enzyme activity is expected to expand the applications of enzyme in a wide range of research fields. We have previously developed a complementary polymer pair system (CPPS) that enables the activity of several enzymes to be controlled by a pair of oppositely charged polymers. However, it failed to control the activity of large and unstable α-amylase because the aggregation of the complex between anionic α-amylase and cationic poly(allylamine) (PAA) induced irreversible denaturation of the enzyme. To address this issue, we herein designed and synthesized a cationic copolymer with a poly(ethylene glycol) backbone, poly(N,N-diethylaminoethyl methacrylate)-block-poly(ethylene glycol) (PEAMA-b-PEG). In contrast to PAA, α-amylase and β-galactosidase were inactivated by PEAMA-b-PEG with the formation of soluble complexes. The enzyme/PEAMA-b-PEG complexes were then successfully recovered from the complex by the addition of anionic poly(acrylic acid) (PAAc). Thus, dispersion of the complex by PEG segment in PEAMA-b-PEG clearly plays a crucial role for regulating the activities of these enzymes, suggesting that PEGylated charged polymer is a new candidate for CPPS for large and unstable enzymes. 相似文献
100.
Tsuzuki S Wakisaka A Ono T Sonoda T 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(3):951-960
The geometries and interaction energies of complexes of pyridine with C6F5X, C6H5X (X=I, Br, Cl, F and H) and RFI (RF=CF3, C2F5 and C3F7) have been studied by ab initio molecular orbital calculations. The CCSD(T) interaction energies (Eint) for the C6F5X–pyridine (X=I, Br, Cl, F and H) complexes at the basis set limit were estimated to be ?5.59, ?4.06, ?2.78, ?0.19 and ?4.37 kcal mol?1, respectively, whereas the Eint values for the C6H5X–pyridine (X=I, Br, Cl and H) complexes were estimated to be ?3.27, ?2.17, ?1.23 and ?1.78 kcal mol?1, respectively. Electrostatic interactions are the cause of the halogen dependence of the interaction energies and the enhancement of the attraction by the fluorine atoms in C6F5X. The values of Eint estimated for the RFI–pyridine (RF=CF3, C2F5 and C3F7) complexes (?5.14, ?5.38 and ?5.44 kcal mol?1, respectively) are close to that for the C6F5I–pyridine complex. Electrostatic interactions are the major source of the attraction in the strong halogen bond although induction and dispersion interactions also contribute to the attraction. Short‐range (charge‐transfer) interactions do not contribute significantly to the attraction. The magnitude of the directionality of the halogen bond correlates with the magnitude of the attraction. Electrostatic interactions are mainly responsible for the directionality of the halogen bond. The directionality of halogen bonds involving iodine and bromine is high, whereas that of chlorine is low and that of fluorine is negligible. The directionality of the halogen bonds in the C6F5I– and C2F5I–pyridine complexes is higher than that in the hydrogen bonds in the water dimer and water–formaldehyde complex. The calculations suggest that the C? I and C? Br halogen bonds play an important role in controlling the structures of molecular assemblies, that the C? Cl bonds play a less important role and that C? F bonds have a negligible impact. 相似文献