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121.
122.
For such curves we know a moving frame and a complete system of invariants (affine curvatures) with respect to the group of volume-conserving transformations (unimodular group) of the order 2n?1 respectively 2n (see [1], p. 171). In this paper we study for a curvec a moving frame and a system of invariants of the minimal ordern+1, respectivelyn+2, by means of a curve with vanishing affine curvatures that has contact of maximal order withc. Forn=3 this is a result ofA. Winternitz ([1], p. 171 or [3], p. 86).  相似文献   
123.
Zusammenfassung Tourenprobleme bei der Hausmüllsammlung lassen sich in die Reihe der Lieferplanprobleme einordnen. Zur Lösung praktischer Größenordnungen werden hier einfache heuristische Verfahren (Prioritätsregeln) vorgestellt, weniger um der Vielzahl heuristischer Verfahren weitere hinzuzufügen als vielmehr dem Praktiker einen vielversprechenden Weg beim Lösen seiner Probleme aufzuzeigen.
Summary The discussed solid waste collection problem shows the properties of the so called truck dispatching problem. To solve problems for typical problem structure heuristic rules are pointed out in order to show the planner an efficient way of problem solving.


Zusammenfassung dreier Vorträge im 4. planungstechnischen Seminar Tourenplanung bei der Abfallbeseitigung am Institut für Siedlungswasserwirtschaft der Universität Karlsruhe am 1.10.1976.  相似文献   
124.
It is the aim of this paper to introduce two new notions of discrepancy. They are defined by the formulas $$\begin{gathered} \Delta _N^r \left( {\omega ;f} \right) = \mathop {\sup }\limits_{\left| z \right| = r} \left| {\left( {{1 \mathord{\left/ {\vphantom {1 N}} \right. \kern-\nulldelimiterspace} N}} \right)\sum\limits_{n = 1}^N {f\left( {z e^2 \pi i\omega \left( n \right)} \right)} - f\left( 0 \right)} \right|, and \hfill \\ \delta _N^r \left( {\omega ;f} \right) = \mathop {\sup }\limits_{\left| z \right| = r} \left| {\left( {{1 \mathord{\left/ {\vphantom {1 N}} \right. \kern-\nulldelimiterspace} N}} \right)\sum\limits_{n = 1}^N {f\left( {z \omega \left( n \right)} \right)} \cdot z - \int\limits_0^z {f\left( \zeta \right)d\zeta } } \right|, \hfill \\ \end{gathered} $$ wheref is a holomorphic function defined in the unit disc withf (k) (0)≠0 for allk∈?,r<1 is a positive number, and ω is a sequence in [0, 1]. The first of these discrepancies can be generalized for multidimensional sequences. ω is uniform distributed if and only if lim N→∞ Δ N r (ω;f)=0 resp. lim N→∞δ N r (ω;f)=0. These results are proved in a quantitative way by estimating the classical discrepancyD N (ω) by means ofΔ N r (ω;f) and δ N r (ω;f): $$\begin{gathered} \Delta _N^r \left( {\omega ;f} \right) \ll D_N \left( \omega \right) \ll \Phi \left( {\Delta _N^r \left( {\omega ;f} \right)} \right), \hfill \\ \delta _N^r \left( {\omega ;f} \right) \ll D_N \left( \omega \right) \ll \Psi \left( {\delta _N^r \left( {\omega ;f} \right)} \right). \hfill \\ \end{gathered} $$ The functions Φ and Ψ only depend onf andr. These estimations are based on the inequalities ofKoksma-Hlawka andErdös-Turán.  相似文献   
125.
The importance of the rheological behaviour of solutions of macromolecules is briefly evaluated. The viscosity of the solutions depends on concentration, shear rate and time of shear, this relation being determined by the structure of the dissolved molecules. In dilute solutions shear dependence of viscosity is very frequently caused by the preferential orientation of anisotropic molecules. In such a case the particle dimensions can be calculated from the true limiting viscosity number, an anisotropy factor, the rotational diffusion constant and the effective particle density. These numbers can be derived from the flow curve, which has been extrapolated to zero concentration. It is necessary to measure the flow curve at shear gradients, which are sufficiently low to allow for an extrapolation to vanishing shear rate. By comparing the experimental flow curve with a choice of theoretical ones, the rotational diffusion constant and the anisotropy factor (axial ratio) can be found. From the limiting viscosity number and the axial ratio, the particle density can be calculated.  相似文献   
126.
Complexes of 2,6-dimethylpyridine 1-oxide with lanthanide iodides of the formulaeLn(2,6-LTNO)5I3 whereLn=La, Tb and Yb,Ln(2,6-LTNO)4I3 whereLn=Pr and Nd and Er(2,6-LTNO)4.5I3 have been prepared and characterised by chemical analysis, infrared and conductance studies. Infrared and conductance data have been interpreted in terms of dimeric (or polymeric) structures involving bridging amine oxide groups.

Mit 2 Abbildungen  相似文献   
127.
The synthesis of 5-(o-trifluoromethylphenyl)-1H-thieno-[3,4-e]1,4-diazepin-2(3H)-one (7) and its nitration and chlorination in pos. 8 are described.  相似文献   
128.
Mean amplitudes of vibration of a series of tetrahedralXY 4 molecules and ions (hydrides, halides, oxides and oxoanions) have been calculated using the “Method of the Characteristic Vibrations” ofA. Müller. The results indicate that this method leads to very good values for most of the investigated species, and especially in the cases of highM X/MY mass ratio.  相似文献   
129.
Zusammenfassung Es wurden die longitudinalen Protonen-RelaxationszeitenT 1 der beiden Systeme Hexamethyldisiloxan und Dekamethylcyclopentasiloxan im Temperaturbereich von 20 bis 300 K untersucht. Das Relaxationsverhalten des Hexamethyldisiloxans wird in diesem Temperaturbereich durch drei Bewegungsmechanismen bestimmt: die Methylgruppenrotation um die C3-Achse, die Segmentrotation um die Si-O-Bindung und einen noch nicht näher identifizierten Bewegungsprozeß, der zu einer sprunghaften Änderung der Spin-Gitter-Relaxationszeit führt. Diese Bewegungsmechanismen werden mit Ausnahme der Segmentrotation auch beim Dekamethylcyclopentasiloxan gefunden. Es wird eine Gegenüberstellung der experimentellen Daten der beiden hier untersuchten Systeme und eines polymeren Dimethylsiloxans gegeben. Dabei ist als interessantes Ergebnis hervorzuheben, daß die Methylgruppenrotation im Hexamethyldisiloxan die stärkste Behinderung erfährt.
Summary In this experiment the longitudinal proton relaxation timesT 1 of hexamethyldisiloxane and decamethylcyclopen-tasiloxane were measured in the temperature range from about 20 K up to 300 K. Three motional mechanisms, the methyl group rotation about the C3-axis, the segmental rotation about the Si-O-bond and a motional process, not yet identified, which leads to a discontinuity ofT 1 have been found to be responsible for the spin-lattice relaxation of hexamethyldisiloxane in this temperature range. With the exception of segmental rotation these motional processes also determine the spin-lattice relaxation of decamethylcyclopentasiloxane. A comparison of experimental data of the two systems actually investigated and a polymeric dimethylsiloxane is presented, showing the methyl group rotation being most strongly hindered in the case of hexamethyldisiloxane.


Mit 4 Abbildungen und 1 Tabelle  相似文献   
130.
The reactions of Ge2(C6H5)6 with HCl and HBr lead in nearly quantitative yields to the 1,1,2,2-tetrahalo derivatives Cl2(C6H5)GeGe(C6H5)Cl2 (I) and Br2(C6H5)GeGe(C6H5)Br2 (II), resp. The Si?Ge bond of (C6H5)3SiGe(C6H5)3 is cleaved under the conditions of hydrohalogenation. The vibrational spectra of Ge2Br6, Ge2(C6H5)6, I, and II are reported. The influence of vibrational coupling on ν GeGe in these compounds is discussed in detail, including vibrational calculations.  相似文献   
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