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901.
T. Furukawa Y. Matsuo A. Hatakeyama K. Fujikake Y. Matsuura T. Kobayashi T. Shimoda 《Hyperfine Interactions》2010,195(1-3):191-197
We have been developing a new laser spectroscopic technique “OROCHI,” which is based on the combination of superfluid helium as a stopper of radioactive isotope (RI) beam and in-situ laser spectroscopy of RI atoms, for determining spins and moments of exotic RIs. By using this unique technique, it is feasible to measure nuclear spins and electromagnetic moments of extremely low yield RI (estimated as less than 1 pps). Recently, we have demonstrated that nuclear spins and moments are obtained from Zeeman and hyperfine splittings of stable Rb isotopes measured using this OROCHI technique. Details of this laser spectroscopy method in He II “OROCHI” and the summary of our development are presented. 相似文献
902.
The principle and recent technical development of adiabatic low temperature calorimetry are described with experimental results taken mostly from the authors' laboratory. Topics on the equilibrium and quasi-equilibrium heat capacities include the separation of the Schottky heat capacity from the experimental data on bromo-hydroxyphenalenone and non-Debye excess heat capacity of a glassy hydrocarbon. Relaxation of glassy crystals of rubidium cyanide and C60 and stabilization of a supercooled phase of methylammonium hexachlorotellurate are discussed. A unique adiabatic calorimeter of top-loading construction recently completed in the authors' laboratory is described along with an experimental result on a glassy liquid prepared at a cooling rate 100 times greater than was possible with a calorimeter of the conventional design. 相似文献
903.
Hideo Tanaka Tomoharu Ebata Isamu Kuwahara Masaru Matsuo James C. Ogbonna 《Applied biochemistry and biotechnology》1999,80(1):51-64
Development and application of a system for real-time quantitative assessment of individual cell activities in a mixed culture
system was investigated. This was based on a concept that the activities of individual cells in a mixed culture can be assessed
if the cells are physically separated (in separate compartments) in a vessel while the culture conditions, including the broth
components, are maintained the same in all the compartments during the cultivation. On this basis, three different apparatus
(M-1, M-2, and M-3) were constructed using various types of membranes. In terms of mass transfer characteristics and membrane
fouling, the M-3 apparatus was the most effective system for analysis of mixed cultures at high cell densities. With the M-3
apparatus, the interrelationships between two alcohol-producing strains (Saccharomyces cerevisiae and Zymomonas mobilis) under anaerobic and aerobic conditions were studied. Under anaerobic condition, except for possible competition for nutrients,
there were no significant effects of the activities of one microorganism on the other. However, under aerobic condition, amensalism
was observed because acetaldehyde that was produced by Z. mobilis inhibited the growth of S. cerevisiae. 相似文献
904.
905.
906.
Norio Kashiwa Shin-ichi Kojoh Nobuo Kawahara Shingo Matsuo Hideyuki Kaneko Tomoaki Matsugi 《Macromolecular Symposia》2003,201(1):319-326
This paper describes a new synthetic route for polyolefinic graft block copolymers by adopting coupling reaction between terminally hydroxylated polyolefins and maleic anhydride grafted polyolefins. Terminally hydroxylated polypropylene (PP-OH) was coupled with maleic anhydride modified polyethylene (PE-g-MAH) and such ethylene-propylene random copolymer (EPR-g-MAH) to give polyolefinic graft block copolymers (PE-g-PP and EPR-g-PP, respectively). The formation of PE-g-PP was confirmed by enhancement on molecular weight and it brought about distinctive decrease in size of dispersed domain in its phase separation morphology. Occurrence of coupling reaction to give EPR-g-PP was indicated by extreme decrease in its solubility to n-decane and it led to unique morphology demonstrating lamella microstructure that had never been reported for a comparable polyolefin composite. 相似文献
907.
Hideyuki Kaneko Shin-ichi Kojoh Nobuo Kawahara Shingo Matsuo Tomoaki Matsugi Norio Kashiwa 《Macromolecular Symposia》2004,213(1):335-346
Polymacromonomers with polyolefin branches were successfully synthesized by free-radical homopolymerization of polyolefin macromonomer with a methacryloyl end group. Propylene-ethylene random copolymer (PER) with a vinylidene end group was prepared by polymerization using a metallocene catalyst. Then, the unsaturated end group was converted to a hydroxy end group via hydroalumination and oxidation. The PER with the hydroxy end group was easily reacted with methacryloyl chloride to produce methacryloyl-terminated PER (PER macromonomer; PERM). The free-radical polymerization of thus-obtained PERM was done using 2,2′-azobis(isobutyronitorile) (AIBN) as a free-radical initiator. From NMR analyses, the obtained polymers were identified as poly(PERM). Based on gel permeation chromatography (GPC), the estimated degree of polymerization (Dp) of these polymers were about 30. Thus, new class of polymacromonomers with polyolefin branches was synthesized. 相似文献
908.
Kazuki Matsuo Tadashi Yoshitake Eiji Yamaguchi Akichika Itoh 《Molecules (Basel, Switzerland)》2021,26(22)
We have developed a photochemical ATRA/ATRC reaction that is mediated by halogen bonding interactions. This reaction is caused by the reaction of malonic acid ester derivatives containing bromine or iodine with unsaturated compounds such as alkenes and alkynes in the presence of diisopropylethylamine under visible light irradiation. As a result of various control experiments, it was found that the formation of complexes between amines and halogens by halogen-bonding interaction occurs in the reaction system, followed by the cleavage of the carbon–halogen bonds by visible light, resulting in the formation of carbon radicals. In this reaction, a variety of substrates can be used, and the products, cyclopentenes and cyclopentanes, were obtained by intermolecular addition and intramolecular cyclization. 相似文献
909.
S. Leoni A. Bracco T. Døssing B. Herskind J.C. Lisle M. Matsuo E. Vigezzi J. Wrzesinski 《The European Physical Journal A - Hadrons and Nuclei》1999,4(3):229-231
The number of discrete rotational bands in the nucleus 168Yb is obtained by a fluctuation analysis of the rotational ridge structure in double and triple γ coincidence matrices. The
data are compared with cranked shell model calculations including a surface delta interaction. It is found that the number
of calculated bands strongly depends on the interaction strength V0, and agreement between data and calculations supports the standard value V0= 27.5/A MeV.
Received: 11 January 1999 相似文献
910.
In the path integral representation, the Hamiltonian in a quantum system is associated with the Hamiltonian in a classical system through the Weyl transformation. From this, it is possible to describe the time evolution in a quantum system by the Hamiltonian in a classical system. In a Bose system, the Weyl transformation is defined by the eigenstates of the canonical operators, since the Hamiltonian is given by a function of the canonical operators. On the other hand, in a Fermi system, the Hamiltonian is usually described by a function of the creation and annihilation operators, and hence the Weyl transformation is defined by the coherent states which are the eigenstate of an annihilation operator. Here, we formulate the Weyl transformation in Fermi systems in terms of the eigenstates of the canonical operators so as to clarify the correspondence between both systems. Using this, we can derive the path integral representation in Fermi systems. 相似文献