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61.
62.
Tamejiro Hiyama Hiroyuki Saimoto Koji Nishio Masaki Shinoda Hajime Yamamoto Hitosi Nozaki 《Tetrahedron letters》1979,20(22):2043-2046
A new method is reported for constructing α-methylene-γ-butyrolactone moiety under neutral, anhydrous conditions. Olefin-dibromocarbene adducts are transformed to methyl 1-(N,N-dimethylaminomethyl)cyclopropanecarboxylates which in turn are treated with trimethylsilyl iodide and the crude products distilled to give the title compounds with high regio- and stereoselectivity. 相似文献
63.
The 3.51 μm HeXe laser is magnetically tuned over a wavenumber of 0.2 cm?1 and used for infrared absorption and double resonance spectroscopy. Eight rotation-vibration lines of propynal in the ν2 band are assigned by the Stark effect. Eleven microwave transitions in the v2 = 1 vibrational state are observed by the method of infrared-microwave double resonance. The rotational constants of the excited state and the band origin of the vibration ν2 are determined from the observed spectra. 相似文献
64.
65.
Hamao Watanabe Kazuaki Higuchi Tomoko Goto Tsutomu Muraoka Jun Inose Masaaki Kageyama Yasuko Iizuka Masakatsu Nozaki Yoichiro Nagai 《Journal of organometallic chemistry》1981,218(1):27-39
In the presence of a catalytic amount of sodium methoxide, sym-dimethoxytetramethyldisilane was converted into α,ω-dimethoxypermethylpolysilanes, MeO(SiMe2)nOMe where n ? 3, at room temperature. On the other hand, similar treatment of the disilane in THF solution gave cyclic polysilanes, (Me2Si)n where n = 5–7. Decomposition of the disilane in the presence of diphenylacetylene afforded a trisilacyclopentene derivative under similar conditions. This compound was obtained also by the reaction between α,ω-dimethoxypermethylpolysilanes and diphenylacetylene in the presence of sodium methoxide. These cyclic products most likely were formed via permethyl polysilyl anion intermediates derived from α,ω-dimethoxypermethylpolysilanes. Also, the formation of α,ω-dimethoxypermethylpolysilanes could be elucidated in terms of the mechanism involving the base-assisted, concerted nucleophilic substitution or stepwise substitution by silyl anions, rather than the successive dimethylsilylene (Me2Si:) insertion reaction. 相似文献
66.
Shigendo Enomoto Ken-ichi Kumagai Taro Tamura Miki Hasegawa Kyoko Nakada Toshihiko Hoshi Michio Kobayashi 《Monatshefte für Chemie / Chemical Monthly》2004,29(1):471-481
Fluoranthene (FA) forms a 1:1 van der Waals complex with benzene in cyclohexane. The 1H NMR spectrum of this complex shows that the FA moiety in the complex state has five kinds of hydrogen atoms and that the 1H NMR peaks assigned to the protons attached to the naphthalene skeleton are largely shifted to higher magnetic field on complex formation with benzene. These observations indicate that the complex takes the structure of CS symmetry, in which the benzene molecule mainly interacts with the electronic system localized on the naphthalene moiety of FA. The present ab initio calculations reproduce well the 1H NMR spectral shifts mentioned above and the experimentally predicted CS structure of the complex. According to the PPP calculations for the electronic absorption spectral changes on the complex formation, the FA-benzene complex is considered to take a sandwich type structure. 相似文献
67.
[reaction: see text] A simultaneous hydroxylation-carboxylation of biphenyl occurred to give 4'-hydroxy-4-biphenylcarboxylic acid, which has wide potential application as a polyester monomer. 相似文献
68.
Treatment of R'CHO with Li[R3BCHCH2] gives an adduct which is believed to be R2BCHR-CH2-CH(OLi)R' (2) or its borate form (3). Oxidation of the adducts with alkaline hydrogen peroxide gives ca. 1:1 mixture of diastereomeric 1,3-alkanediols in good yields. On the other hand, the reaction of BrMg[R3BCHCH2] with R'CHO affords less satisfactory results. Successive treatment of 2 (R = n-Bu, R' = H) with PCl5 and alkaline H2O2 gives HOCHBu-CH2-CH2Cl (6). Treatment of Et2BCHEt-CH2-CHCl-Ph with NaOH aq produces l-ethyl-2-phenylcyclopropane 7. 相似文献
69.
Hideya Kawasaki Tarui Akira Takehiro Watanabe Kazuyoshi Nozaki Tetsu Yonezawa Ryuichi Arakawa 《Analytical and bioanalytical chemistry》2009,395(5):1423-1431
The availability of robust methods for the species-specific detection of meat and bone meal (MBM) in compound feedingstuffs
is an important prerequisite to enforce current and upcoming European legislation on the use of processed animal proteins
in animal nutrition. Among possible methods, those based on DNA turned out to be a reliable tool for this aim, since DNA is
a quite thermostable molecule able to resist severe heat treatments applied in the manufacturing of animal meals. The application
of such methods by control laboratories implies that the method has been validated including an assessment of its robustness.
Successful transferability between laboratories is considered an important robustness criterion of the method. However, corresponding
guidelines regarding the design of such a study relevant to this field are missing. Here, we demonstrate the feasibility of
an alternative concept that was applied to check for the transferability of a qualitative assay for the detection of banned
MBM in feedingstuffs at trace level based on real-time PCR. The concept was based on an experimental nested design applying
analysis of variance (ANOVA) that was conducted independently in two laboratories and which allows for establishing major
factors influencing the result of analysis. Statistical assessment of the results confirmed the importance of the DNA extraction/purification
step utilised, whereas the PCR step turned out to be a minor factor regarding the overall variability of the results. Furthermore,
blind samples comprised of compound feed adulterated with MBM at 0.1 % and blank compound feed were correctly classified as
"positive" or "negative" samples, thus confirming fitness of purpose for the method. This approach can be of interest for
other research groups working in the development of real-time PCR methods and in their use by control laboratories.
Nested design of the study to check for the transferability of the real-time PCR method 相似文献
70.
Yutaka T Obara S Ogawa S Nozaki K Ikeda N Ohno T Ishii Y Sakai K Haga MA 《Inorganic chemistry》2005,44(13):4737-4746
A series of novel emissive Ir(III) complexes having the coordination environments of [Ir(N--N--N)2]3+, [Ir(N--N--N)(N--N)Cl]2+, and [Ir(N--N--N)(N--C--N)]2+ with 2,6-bis(1-methyl-benzimidazol-2-yl)pyridine (L1, N--N--N), 1,3-bis(1-methyl-benzimidazol-2-yl)benzene (L2H, N--C--N), 4'-(4-methylphenyl)-2,2':6',2' '-terpyridine (ttpy, N--N--N), and 2,2'-bipyridine (bpy, N--N) have been synthesized and their photophysical and electrochemical properties studied. The Ir(III) complexes exhibited phosphorescent emissions in the 500-600 nm region, with lifetimes ranging from approximately 1-10 micros at 295 K. Analysis of the 0-0 energies and the redox potentials indicated that the lowest excited state of [Ir(L1)(L2)]2+ possessed the highest contribution of 3MLCT (MLCT = metal-to-ligand charge transfer) among the Ir(III) complexes, reflecting the sigma-donating ability of the tridentate ligand, ttpy < L1 < L2. The emission quantum yields (phi) of the Ir(III) complexes ranged from 0.037 to 0.19, and the highest phi value (0.19) was obtained for [Ir(L1)(bpy)Cl]2+. Radiative rate constants (k(r)) were 1.2 x 10(4) s(-1) for [Ir(ttpy)2]3+, 3.7 x 10(4) s(-1) for [Ir(L1)(bpy)Cl]2+, 3.8 x 10(4) s(-1) for [Ir(ttpy)(bpy)Cl]2+, 3.9 x 10(4) s(-1) for [Ir(L1)2]3+, and 6.6 x 10(4) s(-1) for [Ir(L1)(L2)]2+. The highest radiative rate for [Ir(L1)(L2)]2+ with the highest contribution of 3MLCT could be explained in terms of the singlet-triplet mixing induced by spin-orbit coupling of 5d electrons in the MLCT electronic configurations. 相似文献