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121.
Yoshiki Nakata Noriaki Miyanaga 《Applied Physics A: Materials Science & Processing》2010,98(2):401-405
Combined structures composed of a micron-sized periodic structure and a nano-sized quasi-periodic ripple structure were generated
by a single process of multiple shots of an interfering femtosecond laser. The former structure was generated by an interference
pattern and controlled by a number of beams. The latter structure was generated by a multiple shot method. As a result, multiple
periodic structures were generated. The periodicity of the structures was analyzed by two-dimensional (2D) fast Fourier transform
(FFT). The most probable period of ripple structure was downsized to 177 nm by restricting irradiated region by a TM wave
interference pattern. The smallest period was 105 nm. The dispersion angle of a ripple decreased to about 50%. The period
and direction of the ripples were for a first time controlled by using interference. 相似文献
122.
Yoshiki Wada Nobuyuki Matsushita Masahiro Yamashita 《Molecular Crystals and Liquid Crystals》2013,570(1):891-896
Abstract Photo-induced absorption (PA) spectra of [Pt (en)2] [Pt (en)2X2] (SO2)2. 6H2O (X=Cl and Br) have been measured. Large excitation photon energy dependent changes were found in the features of the PA spectra. The excitation photon energy dependences are considered to be due to the difference between the relaxation processes of the charge transfer excitons and those of the higher energy excited states. Several new PA bands have been found. 相似文献
123.
Yoshiki Otobe 《Stochastics An International Journal of Probability and Stochastic Processes》2013,85(1-2):489-516
We consider a time evolution of random fields with non-negative values on the real line. Such evolution is described by an infinite dimensional stochastic differential equation of Skorokhod's type, which is a stochastic partial differential equation (SPDE) of parabolic type with reflection. We shall show the existence of the solution, and its uniqueness when the diffusion coefficient is constant. 相似文献
124.
125.
The change in intensity and frequency of O-H stretching band upon intramolecular hydrogen bonding was sufficiently examined for various proton acceptors of many alicyclic substances. The order of proton acceptors to bring about the intensity increase of constant degree is: Some discussions are given on these. 相似文献
126.
A Highly Efficient Near‐Infrared‐Emissive Copolymer with a N=N Double‐Bond π‐Conjugated System Based on a Fused Azobenzene–Boron Complex 下载免费PDF全文
Masayuki Gon Kazuo Tanaka Yoshiki Chujo 《Angewandte Chemie (International ed. in English)》2018,57(22):6546-6551
Fused azobenzene–boron complexes (BAzs) show highly efficient near‐infrared (NIR) emission from the nitrogen–nitrogen double bond (N=N) containing π‐conjugated copolymer. Optical measurements showed that BAz worked as a strong electron acceptor because of the intrinsic electron deficiency of the N=N double bond and the boron–nitrogen (B?N) coordination which dramatically lowered the energy of the lowest unoccupied molecular orbital (LUMO) of the azobenzene ligand. The simple donor–acceptor (D–A) type copolymer of bithiophene (BT) and BAz exhibited intense photoluminescence (PL) in the NIR region both in the dilute solution (λPL=751 nm, ΦPL=0.25) and in the film (λPL=821 nm, ΦPL=0.038). The BAz monomer showed slight PL in the dilute solution, and aggregation‐induced emission (AIE) was detected. We proposed that N=N double bonds should be attractive and functional building blocks for designing π‐conjugated materials. 相似文献
127.
Direct Participation of a Peripheral Side Chain of a Corrin Ring in Coenzyme B12 Catalysis 下载免费PDF全文
Dr. Naoki Shibata Yui Sueyoshi Prof. Dr. Yoshiki Higuchi Prof. Dr. Tetsuo Toraya 《Angewandte Chemie (International ed. in English)》2018,57(26):7830-7835
The crystal structures of the B12‐dependent isomerases (eliminating) diol dehydratase and ethanolamine ammonia‐lyase complexed with adenosylcobalamin were solved with and without substrates. The structures revealed that the peripheral a‐acetamide side chain of the corrin ring directly interacts with the adenosyl group to maintain the group in the catalytic position, and that this side chain swings between the original and catalytic positions in a synchronized manner with the radical shuttling between the coenzyme and substrate/product. Mutations involving key residues that cooperatively participate in the positioning of the adenosyl group, directly or indirectly through the interaction with the a‐side chain, decreased the turnover rate and increased the relative rate of irreversible inactivation caused by undesirable side reactions. These findings guide the engineering of enzymes for improved catalysis and producing useful chemicals by utilizing the high reactivity of radical species. 相似文献
128.
The Electronic State of Hydrogen in the α Phase of the Hydrogen‐Storage Material PdH(D)x: Does a Chemical Bond Between Palladium and Hydrogen Exist? 下载免费PDF全文
Shun Dekura Prof. Hirokazu Kobayashi Prof. Ryuichi Ikeda Prof. Mitsuhiko Maesato Haruka Yoshino Prof. Masaaki Ohba Prof. Takayoshi Ishimoto Dr. Shogo Kawaguchi Prof. Yoshiki Kubota Dr. Satoru Yoshioka Prof. Syo Matsumura Prof. Takeharu Sugiyama Prof. Hiroshi Kitagawa 《Angewandte Chemie (International ed. in English)》2018,57(31):9823-9827
The palladium–hydrogen system is one of the most famous hydrogen‐storage systems. Although there has been much research on β‐phase PdH(D)x, we comprehensively investigated the nature of the interaction between Pd and H(D) in α‐phase PdH(D)x (x<0.03 at 303 K), and revealed the existence of Pd?H(D) chemical bond for the first time, by various in situ experimental techniques and first‐principles theoretical calculations. The lattice expansion, magnetic susceptibility, and electrical resistivity all provide evidence. In situ solid‐state 1H and 2H NMR spectroscopy and first‐principles theoretical calculations revealed that a Pd?H(D) chemical bond exists in the α phase, but the bonding character of the Pd?H(D) bond in the α phase is quite different from that in the β phase; the nature of the Pd?H(D) bond in the α phase is a localized covalent bond whereas that in the β phase is a metallic bond. 相似文献
129.
The molecular structure of malagashanine (C23H30N2O4), a new alkaloid occurring in MadagascanStrychnos species and showing chloroquine-potentiating action, has been determined by single crystal X-ray diffraction. The crystals, in the form of a 11 acetone solvate, are monoclinic, space group P21, witha=10.328(2),b=10.554(6),c=11.490(5)Å, =96.67(2)0,Z=2. Refinement based on 3650 reflections measured at 294K yieldedR=0.045. The X-ray analysis shows that the ring system in malagashanine differs from that in alkaloids of the strychnobrasiline type in containing only five-and six-membered rings. Thermal analysis of the solvate indicates that the acetone molecules are firmly held in the crystal and the X-ray analysis reveals that they are trapped in crystal voids. Only van der Waals forces and C–H...O hydrogen bonds stabilize the crystal structure. 相似文献
130.
Zeynep Ates-Alagoz Sibel Suzen Erdem Buyukbingol Mino R. Caira 《Journal of chemical crystallography》2000,30(2):103-107
As part of a program investigating the conformations of potential anticarcinogens and antioxidants, the structure of the title compound C24H28N2O2·H2O is reported. The monohydrate crystallizes in the monoclinic space group P2/c with unit cell parameters a = 16.184(1),b = 7.937(1), c = 16.968(1), = 92.788(7)°, and Z = 4. The benzimidazole and tetrahydrotetramethylnaphthalene ring systems are inclined to one another by approximately 26°. The water molecule plays an important role in the crystal structure by hydrogen bonding to different functional groups of three organic moieties. Additional crystal stabilization is dueto – stacking of benzimidazole rings. 相似文献