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121.
Ohne Zusammenfassung 相似文献
122.
M. Asai J. L. Bailly H. B?ttcher F. Bruyant C. Caso Y. Chiba H. Dibon B. Epp A. Ferrando F. Fontanelli S. N. Ganguli T. Gémesy R. Hamatsu P. Hidas T. Hirose J. Hrubec T. Kageya N. Khalatyan E. Kistenev I. Kita S. Kitamura V. Kubik J. MacNaughton M. Markytan S. Matsumoto I. S. Mittra L. Montanet G. Neuhofer G. Pinter P. Porth T. Rodrigo J. Singh S. Squarcia K. Takahashi R. Tanaka L. A. Tikhonova U. Trevisan R. Wischnewski T. Yamagata S. A. Zotkin NA EHS-RCBC Collaboration 《Zeitschrift fur Physik C Particles and Fields》1990,46(4):593-598
Properties of proton diffractive dissociation have been investigated for four-prong final states in proton-proton reactions at 360 GeV/c, in particular forpp→ppπ +π? mπ 0(m=0,1,2). Mass distributions and decay angular distributions are given. The decay of the diffractive system is seen to be very anisotropic, and largep T is suppressed at higher masses. It is found that the “pomeron” couples with a single valence quark of the incident proton, but indications for a diquark-pomeron coupling are also found. Similarities with fragmentation in lepton-hadron deep inelastic scattering are underlined. 相似文献
123.
R. Göttgens J. M. Kohli P. Sixel H. Böttcher H. Vogt R. Contri H. Dreverman D. R. O. Morrison R. T. Ross T. Coghen J. Figiel B. Madeyski K. W. J. Barnham J. Wells P. R. S. Wright M. Zomorrodian F. Kroener F. Mandl M. Markytan M. Bardadin-Otwinowska A. Jachołkowska M. Szczekowski A. Wroblewski 《Zeitschrift fur Physik C Particles and Fields》1981,11(3):189-194
Multiplicity distributions and correlations between charged particles in the forward and back-ward c.m. hemispheres are studied inK ?p interactions at 110 GeV/c and compared with other data on mesonnucleon scattering. The interpretation in terms of a simple quark-parton picture assuming that the forward multiplicity is dominated by quark fragmentation and the backward multiplicity by diquark fragmentation is supported by the experimental fact that the forward and the backward mean multiplicities are approximately equal to half of thee + e ? andpp multiplicities, respectively. The 110 GeV/cK ?p data show significant correlations between the numbers of slow forward and slow backward particles, whereas the multiplicities of fast forward and fast backward particles are independent. 相似文献
124.
M. Deutschmann G. Otter H. Böttcher H.J. Schreiber V.T. Cocconi G. Kellner D.J. Kocher D.R.O. Morrison H. Saarikko K.L. Wernhard D. Kuhn R.M. Eason B. Pollock F. Mandl M. Markytan 《Physics letters. [Part B]》1978,73(1):96-98
A total of 101 ω? decays have been found in K?p interactions at 10 and . The decay angular distribution has been fitted under the assumptions that the ω? has spin either . It has been found that the probability of isotropy (spin is less than one in a thousand, whereas the probability for spin is about 70%. Thus, we exclude the spin assignment. The lifetime of the ω? is found to be (1.41?0.24+0.15) × 10?10s, in agreement with our earlier result based on about of the present sample. 相似文献
125.
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127.
Dänicke S Böttcher W Simon O Jeroch H 《Isotopes in environmental and health studies》2001,37(3):213-225
An experiment was carried out to measure fractional muscle protein synthesis rates (k(s)) in broilers with injection of a flooding dose of phenylalanine (1 ml/100 g body weight of 150 mM phenylalanine; 38 atom percent excess (APE) [15N]phenylalanine). K(s) was calculated from the [15N] enrichment in phenylalanine of tissue-free and protein-bound phenylalanine using both gas chromatography mass spectrometry (GC-MS) and gas chromatography combustion isotope ratio mass spectrometry (GC-C-IRMS) for measurements after a 10 min isotope incorporation period. The tertiary-butyldimethylsilyl (t-BDMS) derivatives of phenylalanine were used for gas chromatographic separation in both systems. GC-MS and GC-C-IRMS were calibrated for a range of 7 to 37 [15N]APE and 0 to 0.62 [15N]APE, respectively, and for sample sizes of 0.45 to 4.5 nmol phenylalanine and 7 to 40 nmol phenylalanine, respectively. Reproducibility of standards as a measure of precision varied from 0.06 to 0.29 [15N]APE and from 0.0004 to 0.0018 [15N]APE in GC-MS and GC-C-IRMS, respectively. K(s) was measured in the m. pectoralis major of broilers fed rye based diets (56%) which were provided either unsupplemented (-) or supplemented (+) with an enzyme preparation containing xylanase. K(s) in breast muscles was significantly increased from 21.8%/d to 23.9%/d due to enzyme supplementation. It can be concluded from the study that the measurement of protein synthesis in broilers with the flooding dose technique can be carried out by using [15N]phenylalanine, GC-MS and GC-C-IRMS. 相似文献
128.
A. Böttcher 《Integral Equations and Operator Theory》2001,41(1):123-125
Recently, Borodin and Okounkov [2] established a remarkable identity for Toeplitz determinants. Two other proofs of this identity were subsequently found by Basor and Widom [1], who also extended the formula to the block case. We here give one more proof, also for the block case. This proof is based on a formula for the inverse of a finite block Toeplitz matrix obtained in the late seventies by Silbermann and the author. 相似文献
129.
Dr. Tobias Böttcher Simon Steinhauer Dr. Lesley C. Lewis‐Alleyne Beate Neumann Dr. Hans‐Georg Stammler Dr. Bassem S. Bassil Prof. Dr. Gerd‐Volker Röschenthaler Prof. Dr. Berthold Hoge 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(2):893-899
The addition of BCl3 to the carbene‐transfer reagent NHC→SiCl4 (NHC=1,3‐dimethylimidazolidin‐2‐ylidene) gave the tetra‐ and pentacoordinate trichlorosilicon(IV) cations [(NHC)SiCl3]+ and [(NHC)2SiCl3]+ with tetrachloroborate as counterion. This is in contrast to previous reactions, in which NHC→SiCl4 served as a transfer reagent for the NHC ligand. The addition of BF3 ? OEt2, on the other hand, gave NHC→BF3 as the product of NHC transfer. In addition, the highly Lewis acidic bis(pentafluoroethyl)silane (C2F5)2SiCl2 was treated with NHC→SiCl4. In acetonitrile, the cationic silicon(IV) complexes [(NHC)SiCl3]+ and [(NHC)2SiCl3]+ were detected with [(C2F5)SiCl3]? as counterion. A similar result was already reported for the reaction of NHC→SiCl4 with (C2F5)2SiH2, which gave [(NHC)2SiCl2H][(C2F5)SiCl3]. If the reaction medium was changed to dichloromethane, the products of carbene transfer, NHC→Si(C2F5)2Cl2 and NHC→Si(C2F5)2ClH, respectively, were obtained instead. The formation of the latter species is a result of chloride/hydride metathesis. These compounds may serve as valuable precursors for electron‐poor silylenes. Furthermore, the reactivity of NHC→SiCl4 towards phosphines is discussed. The carbene complex NHC→PCl3 shows similar reactivity to NHC→SiCl4, and may even serve as a carbene‐transfer reagent as well. 相似文献
130.