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1.
Wagner F Gruber O Lackner K Murmann HD Speth E Becker G Bosch HS Brocken H Cattanei G Dorst D Eberhagen A Elsner A Erckmann V Fussmann G Gehre O Gernhardt J Gierke Gv Glock E Grieger G Grigull P Haas G Hacker H Hartfuss HJ Jäckel H Jaenicke R Janeschitz G Junker J Karger F Kasparek W Keilhacker M Kick M Klüber O Kornherr M Kroiss H Kuehner M Lenoci M Lisitano G Maassberg M Mahn C Marlier S Mayer HM McCormick K Meisel D Mertens V Müller ER Müller Müller G Niedermeyer H Ohlendorf W 《Physical review letters》1986,56(20):2187-2190
2.
The phonon spectrum of high energy heat pulses (104W/cm2) generated by current pulses in thin evaporated metal films was studied in ruby by time resolved optical spectroscopy. The experiments show that the population temperature of the phonon states rises with rising phonon energies in accordance with theoretical predictions of Perrin and Budd [1, 2]. The thermalization of the phonon spectrum needs a time of approximately 900 µs in ruby flushed with cold helium gas.This work was supported by the Deutsche Forschungsgemeinschaft, SFB65 相似文献
3.
Wang Zhong-Ming Lin Hua-Kuan Zhou Zhi-Fen Zhu Shou-Rong Chen Yun-Ti Murmann R. Kent 《Transition Metal Chemistry》2000,25(5):562-567
The kinetics of the reaction of CH2O with a quasi-aromatic metal complex (1,1,2,8,9,9-hexamethyl-4,6-dioxa-5-hydro-3,7,10,14-tetraazacyclotetradecane-2,7,10,12-tetraene)copper(II), [Cu(PnAO)-6H]0 (AH), have been studied spectrophotometrically under neutral conditions in 1/3(v/v) MeOH–H2O. The Cu, 2N, 3C quasi-aromatic heterocyclic ring in AH is highly reactive towards CH2O at the central-aromatic-carbon atom, C(12) and the following reaction mechanism is proposed.
The compounds AH, A—CH2OH and A—CH2—A were isolated and identified by i.r spectroscopy and by elemental analysis. The kinetic data supported the proposed reaction sequence. All reactions were second order overall. The rate constants and corresponding activation parameters for every step were obtained and are discussed. 相似文献
4.
The rate of oxygen exchange between trans-[Re(py)4O2]+ and solvent water in pypyH+ buffer solution follows simple first-order kinetics and both oxygens are equivalent. The half-life for isotopic oxygen exchange is about 12 h at a pH of 5.0, 25°C, and [py] = 0.10 M. The observed rate constant for exchange increases with acidity, in the pH range 4 to 6, decreases with [py], and is nearly independent of ionic strength. A small but significant increase of kobs occurs with increasing complex concentration. The rate of exchange follows the rate equation kobs/2 = k0 + k1/[py] with k0 = 1.4 × 10?5(2) s?1 and k1 = 4.7 × 10?7(1) M, s?1 at 25°C. The activation parameters for the reaction at pH = 7.15 (predominately the k0 term) are: ΔH* = +137.(1) kJ/M and ΔS* = +126.(1) J/MK. The pH effect and complex concentration effect are discussed in mechanistic terms. These results are compared to those found for [Re(en)2O2]+ and [Re(CN)4O2]3?. 相似文献
5.
6.
Ernst Murmann 《Fresenius' Journal of Analytical Chemistry》1897,36(1):380-381
Ohne Zusammenfassung 相似文献
7.
8.
Ernst Murmann 《Fresenius' Journal of Analytical Chemistry》1909,48(12):790-792
Ohne Zusammenfassung 相似文献
9.
10.
Summary [MoOCl5]2– aquates rapidly in solutions ofca. 5 M or less in HCl or MeSO3H to give an intermediate which changes to the well known ion, Mo2O
4aq
2+
at a lower rate. Solutions of molybdenum(V) in 12M MeSO3H, when diluted, also change at a similar rate to Mo2O
4
2+
. The rate of reaction, d[Mo2O
4
2+
]/ dt=k[MoV] has a value of k=30.(1)s–1 at 0°C in 5.00 MMeSO3H. At constant ionic strength, k is nearly independent of acidity (5.2–0.5 M) and is only slightly affected by exchanging MeSO
3
–
with Cl– orp-toluenesulfonate ion. At low ionic strength k increases dramatically. In 4.78 MMeSO3H, the activation parameters are: H=72.68(29) kJ/mole, S=16.63(8) jmole · K and k=5.01(5)×102s–1 at 0°C.18O measurements on the oxygen transfer between MoO
aq
3+
and Mo2O
4aq.
2+
were partially inconclusive. A mechanistic interpretation is given to the kinetic results. The x-ray crystal structure of KMoOCl4(OH2)·H2O is reported.On leave from Daegu University, Daegu, Korea. 相似文献