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321.
Kousuke Moritani Michihiro Hashinokuchi Takahiro Kashiwagi Kozo Mochiji 《Applied Surface Science》2008,255(4):948-950
A new cluster time-of-flight secondary ion mass spectrometry (TOF-SIMS) was developed using a size-selected gas cluster ion as a projectile. Since a large gas cluster ion can generate many low-energy constituent atoms in a collision with the surface, it causes multiple and ultra low-energy sputtering. The mean kinetic energy of constituent atoms is provided by dividing the acceleration energy of the gas cluster ion by the number of constituent atoms. Therefore, the sputtering can be controlled to minimize the decomposition of sample molecules and substrate material by precisely adjusting the number of constituent atoms (the cluster size) and/or acceleration energy of the gas cluster ion. The cluster size was selected on the basis of the time-of-flight method using two ion deflectors attached along the ion-beam line. A high resolution of 11.7 was achieved for the cluster size/size width (M/ΔM) of Ar-cluster ions. 相似文献
322.
Proposal of a semiconductor ring laser gyroscope 总被引:1,自引:0,他引:1
Taguchi Kozo Fukushima Kaname Ishitani Atsuyuki Ikeda Masahiro 《Optical and Quantum Electronics》1999,31(12):1219-1226
We proposed a novel optical inertial rotation sensor using a semiconductor ring laser (SRL). The frequency difference between the two counter propagating oscillation frequencies was automatically generated in a mechanically rotated SRL, which consisted of a pig-tailed laser diode amplifier module. And the Sagnac frequency shift could be detected at the first time as a beat note by the terminal voltage change of the SRL without branching the circulating optical power. These experimental results verify that an SRL operates as an optical inertial rotation sensor based on the Sagnac effect. 相似文献
323.
Masaaki Yoshifuji Hiroaki Takahashi Kazuho Shimura Kozo Toyota Ken Hirotsu Kengo Okada 《Heteroatom Chemistry》1997,8(5):375-382
Dibenzocycloheptenylidene(2,4,6-tri-t-butylphenyl)-phosphine and fluorenylidene(2,4,6-tri-t-butylphenyl)-phosphine were prepared by the reactions of lithium silylphosphide with benzosuberenone and fluorenone, respectively. The reactions of the phosphines with sulfur were carried out to compare the results with those of the corresponding diphenyl derivative, and the new findings are discussed in terms of steric hindrance based on the results of the X-ray crystallographic analyses for dibenzocycloheptenylidenephosphine and its sulfide and the computational structure for the fluorenyl derivative. © 1997 John Wiley & Sons, Inc. Heteroatom Chem 8: 375–382, 1997 相似文献
324.
The N-(9-fluorenyl)-N-mesitylamino group was utilized as an electron-donating new sterically protecting group and thus several captodative 1-amino-2-aryldiphosphenes were prepared. The push-pull substituent effect on the -PP- bond was demonstrated by 31P NMR, and the reactivities of the captodative diphosphenes were studied. 相似文献
325.
Optical forces acting on a micro-sphere were studied to corroborate the single-beam fiber optic trap. Transverse optical force acted to pull the micro-sphere back to the beam axis, but axial force always acted in the direction away from the optical fiber end because the laser beam from optical fiber could not be strongly focused. A stable two-dimensional optical trapping could be obtained by the weakly focused laser beam from the fiber end inserted at an angle. 相似文献
326.
A novel dual-beam trapping system was proposed and discussed for a three-dimensional optical trapping of an object with large relative refractive index. From theoretical studies, we confirmed that our system was useful for manipulating objects in cosmic space. 相似文献
327.
Kozo Matsumoto Ryuji Nishimura Hiroaki Mazaki Hideki Matsuoka Hitoshi Yamaoka 《Journal of polymer science. Part A, Polymer chemistry》2001,39(21):3751-3760
Fluorine‐containing amphiphilic ABA triblock copolymers, poly(2‐hydroxyethyl vinyl ether)‐block‐poly[2‐(2,2,3,3,3‐pentafluoropropoxy)ethyl vinyl ether]‐block‐poly(2‐hydroxyethyl vinyl ether) [poly(HOVE‐b‐PFPOVE‐b‐HOVE)] (HFH), poly[2‐(2,2,3,3,3‐pentafluoropropoxy)ethyl vinyl ether]‐block‐poly(2‐hydroxyethyl vinyl ether)‐block‐poly[2‐(2,2,3,3,3‐pentafluoropropoxy)ethyl vinyl ether] [poly(PFPOVE‐b‐HOVE‐b‐PFPOVE)] (FHF), and poly(n‐butyl vinyl ether)‐block‐poly(2‐hydroxyethyl vinyl ether)‐block‐poly(n‐butyl vinyl ether) [poly(NBVE‐b‐HOVE‐b‐NBVE)] (LHL), were synthesized, and their behavior in water was investigated. The aforementioned polymers were prepared by sequential living cationic polymerization of 2‐acetoxyethyl vinyl ether (AcOVE) and PFPOVE or NBVE, followed by hydrolysis of acetyl groups in polyAcOVE. FHF and LHL formed a hydrogel in water, whereas HFH gave a homogeneous aqueous solution. In addition, the gel‐forming concentration of FHF was much lower than that of corresponding LHL. Surface‐tension measurements of the aqueous polymer solutions revealed that all the triblock copolymers synthesized formed micelles or aggregates above about 1.0 × 10?4 mol/L. The surface tensions of HFH and FHF solutions above the critical micelle concentration were lower than those of LHL, indicating high surface activity of fluorine‐containing triblock copolymers. Small‐angle X‐ray scattering measurements revealed that HFH formed a core‐shell sperical micelle in 1 wt % aqueous solutions, whereas the other block copolymers caused more conplicated assembly in the solutions. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 3751–3760, 2001 相似文献
328.
The title compound was prepared by sulfurization of a 1-phosphaallene and its x-ray structure analysis showed the following notable features of the thiaphosphirane ring: P-S = 2.101(2), P-C = 1.770(5) and S-C = 1.767(5) Å (remarkably short), and ∠SPC = 53.5(2), ∠PSC = 53.6(2) and ∠PCS = 72.9(2)°. 相似文献
329.
Dr. Tsuyoshi Murata Kenta Yoshida Dr. Shuichi Suzuki Dr. Akira Ueda Dr. Shinsuke Nishida Dr. Junya Kawai Dr. Kozo Fukui Prof. Dr. Kazunobu Sato Prof. Dr. Takeji Takui Prof. Dr. Kazuhiro Nakasuji Prof. Dr. Yasushi Morita 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(52):e202201426
A novel neutral diradical of π-extended phenalenyl derivative having three oxo-groups, tri-tert-butyl-1,4,7-trioxophenalenyl, and two types of the corresponding σ-dimers were investigated. Quantum chemical calculations showed that the neutral diradical is in triplet ground state having doubly degenerate singly occupied molecular orbitals. The neutral diradical undergoes a σ-dimerization, generating two types of σ-dimers immediately after the preparation. One of the σ-dimers, which was selectively generated in the crystalline state, was a close-shell dimer linked through double-σ-bonds on the phenalenyl skeleton with a long C−C bond length of 1.66 Å. The other σ-dimer, which existed only in the solution state, was a peroxy-linked open-shell dimer in which one σ-bond was formed between two oxygen atoms. Furthermore, the temperature-dependent 1H NMR and ESR spectra revealed that these σ-dimers are in equilibrium in the solution state by the reversible σ-bond formation/cleavage via the neutral diradical as a key intermediate. 相似文献
330.
Yukiko Inoue Kozo Matsumoto Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》2015,53(9):1076-1081
Polyaddition of bis(five‐membered cyclic dithiocarbonate), 2,2‐bis[4‐(1,3‐thioxolane‐2‐one‐4‐yl‐methoxy)phenyl]propane ( 1 ), with diamines having soft oligoether segments and property of the obtained poly(thiourethane)s were examined. Treatment of 1 with equivalent diamines in tetrahydrofuran at room temperature gave poly(thiourethane)s having a mercapto group in each unit, which were further treated with acetic anhydride and triethylamine to give the corresponding S‐acetylated poly(thiourethane)s in high yield. Exposing the mercapto group containing poly(thiourethane)s to benzoyl chloride and triethylamine provided the corresponding S‐benzoylated poly(thiourethane)s effectively. Thermal properties of the obtained polymers were evaluated by thermogravimetric analysis and differential scanning calorimetry. The obtained polymers showed 10 wt % loss temperature (Td10) in the range from 230 to 274 °C, which was relatively high when compared with the Td10 of an analogous polymer prepared from 1 and 1,6‐hexamethylenediamine. The polymers obtained here exhibited glass transition temperature (Tg) in the range from ?16 °C to 40 °C, which was much lower than the analogous polymer described above, probably due to the soft oligoether segments. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 1076–1081 相似文献