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81.
High-power 2.8 W blue-violet InGaN LD was fabricated, applying AlN facet coating technology. The AlN was found to be crystallized on the facets and very stable even after 2200 h cw operation. Luminous flux over 380 lm is obtained with a phosphor-converted LD excitation white light source using just a single laser chip at 1A operating current. 相似文献
82.
Jumpei Saito Manabu Tanaka Kenji Miyatake Masahiro Watanabe 《Journal of polymer science. Part A, Polymer chemistry》2010,48(13):2846-2854
A new series of sulfonated polyimide (SPI) copolymers containing NH, OH, or COOH groups were synthesized by the polycondensation of 1,4,5,8‐naphthalnetetracarboxylic dianhydride, 3,3′‐bis(sulfopropoxy)‐4,4′‐diaminobiphenyl, and 3‐(4‐aminophenyl)‐5‐(3‐aminophenyl)‐1H‐1,2,4‐triazole (SPI‐8‐m), 3,5‐bis(4‐aminophenyl)‐1H‐1,2,4‐triazole (SPI‐8‐p), 3,6‐diaminocarbazole (SPI‐9), 3,5‐diamino‐1H‐1,2,4‐triazole (SPI‐10), bis(3‐aminopropyl)‐amine (SPI‐11), 2,6‐diaminopurine (SPI‐12), 2,4‐diamino‐6‐hydroxyprymidine (SPI‐13), or 3,5‐bis(4‐aminophenoxy)benzoic acid (SPI‐14). The obtained SPIs were soluble in polar organic solvents and gave tough and flexible membranes by solution casting. The SPI membranes having NH and COOH groups showed high thermal (decomposition temperature ≈200 °C) and mechanical (maximum stress >22 MPa) stability. Introducing NH groups, especially triazole and carbazole groups, was effective in improving proton conductive properties of SPI membranes at low humidity. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 2846–2854, 2010 相似文献
83.
H. Baba N. Takahashi A. Yokoyama T. Saito 《Journal of Radioanalytical and Nuclear Chemistry》1999,239(1):103-108
The reaction of238U with12C was studied radiochemically with the purpose of elucidating fast fission characteristics. Fast fission component was extracted
in far-asymmetric mass region and interpreted as the mass diffusion following the Fokker-Planck equation. Anomalous charge
dispersion widths in the corresponding mass region and a sudden increase of the whole mass distribution width at the critical
energy were also observed to support the above interpretation. The reaction time of fast fission was determined to be 5·10−21 s from the width and position of the mass distribution. 相似文献
84.
85.
86.
Liquid scintillation counting of40K in ordinary potassium propionate is a highly suitable experimental task in the general education on radioactivity. The counting
efficiency is about 90%, depending little on the measurement conditions. Potassium propionate is of suitable properties and
can be easily obtained commercially or by conversion from other compounds. The result of counting, about 1,700 cpm/g, is highly
impressive to many students, indicating the existence of40K radioactivity unexpectedly high in the normal nature, and can be used for the exercise of calculating our internal radiation
exposure. 相似文献
87.
Shinji Ejiri Sinya Aoki Tetsuo Hatsuda Kazuyuki Kanaya Yoshiyuki Nakagawa Hiroshi Ohno Hana Saito Takashi Umeda 《Central European Journal of Physics》2012,10(6):1322-1325
We study the QCD phase structure at high temperature and density adopting a histogram method. Because the quark determinant is complex at finite density, the Monte-Carlo method cannot be applied directly. We use a reweighting method and try to solve the problems which arise in the reweighting method, i.e. the sign problem and the overlap problem. We discuss the chemical potential dependence of the probability distribution function in the heavy quark mass region and examine the applicability of the approach in the light quark region. 相似文献
88.
The steady-shear viscosity, dynamic viscoelasticity, and sedimentation behavior were measured for silica suspensions dispersed
in aqueous solutions of poly(ethylene oxide) (PEO). For suspensions prepared with polymer solutions in which the transient
network is developed by entanglements, the viscosity at a given shear rate decreases, shows a minimum, and then increases
with increasing particle concentration. Because the suspensions are sterically stabilized under the conditions where the particle
surfaces are fully covered with by a thick layer of adsorbed polymer, the viscosity decrease can be attributed to the reduction
of network density in solution. But under the low coverage conditions, the particles are flocculated by bridging and this
leads to a viscosity increase with shear-thinning profiles. The polymer chains with high molecular weights form flexible bridges
between particles. The stress-dependent curve of storage modulus measured by a stress amplitude sweep shows an increase prior
to a drastic drop due to structural breakdown. The increase in elastic responses may arise from the restoring forces of extended
bridges with high deformability. The effect of PEO on the rheological behavior of silica suspensions can be explained by a
combination of concentration reduction of polymer in solution and flocculation by bridging. 相似文献
89.
Prof. Shingo Saito Toshiki Sakamoto Naoki Tanaka Ryo Watanabe Takuya Kamimura Kazuki Ota Kathryn R. Riley Keitaro Yoshimoto Yuiko Tasaki-Handa Masami Shibukawa 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(39):10058-10067
In DNA aptamer selection, existing methods do not discriminate aptamer sequences based on their binding affinity and function and the reproducibility of the selection is often poor, even for the selection of well-known aptamers like those that bind the commonly used model protein thrombin. In the present study, a novel single-round selection method (SR-CE selection) was developed by combining capillary electrophoresis (CE) with next generation sequencing. Using SR-CE selection, a successful semi-quantitative and semi-comprehensive aptamer selection for thrombin was demonstrated with high reproducibility for the first time. Selection rules based on dissociation equilibria and kinetics were devised to obtain families of analogous sequences. Selected sequences of the same family were shown to bind thrombin with high affinity. Furthermore, data acquired from SR-CE selection was mined by creating sub-libraries that were categorized by the functionality of the aptamers (e. g., pre-organized aptamers versus structure-induced aptamers). Using this approach, a novel fluorescent molecular recognition sensor for thrombin with nanomolar detection limits was discovered. Thus, in this proof-of-concept report, we have demonstrated the potential of a “DNA Aptaomics” approach to systematically design functional aptamers as well as to obtain high affinity aptamers. 相似文献
90.
Ahmad A. Salaimeh Jeffrey J. Campion Belal Y. Gharaibeh Martin E. Evans Kozo Saito 《Infrared Physics & Technology》2011,54(6):517-524
Quantifying viable bacteria in liquids is important in environmental, food processing, manufacturing, and medical applications. Since vegetative bacteria generate heat as a result of biochemical reactions associated with cellular functions, thermal sensing techniques, including infrared thermography (IRT), have been used to detect viable cells in biologic samples. We developed a novel method that extends the dynamic range and improves the sensitivity of bacterial quantification by IRT. The approach uses IRT video, thermodynamics laws, and heat transfer mechanisms to directly measure, in real-time, the amount of energy lost as heat from the surface of a liquid sample containing bacteria when the specimen cools to a lower temperature over 2 min. We show that the Energy Content (EC) of liquid media containing as few as 120 colony-forming units (CFU) of Escherichia coli per ml was significantly higher than that of sterile media (P < 0.0001), and that EC and viable counts were strongly positively correlated (r = 0.986) over a range of 120 to approximately 5 × 108 CFU/ml. Our IRT approach is a unique non-contact method that provides real-time bacterial enumeration over a wide dynamic range without the need for sample concentration, modification, or destruction. The approach could be adapted to quantify other living cells in a liquid milieu and has the potential for automation and high throughput. 相似文献