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121.
122.
Dr. Gerd Schmidt 《Mathematical Methods of Operations Research》1967,11(1):95-110
Zusammenfassung Zweck dieser Untersuchungen ist es, für einGI|G|1) — Servicesystem ohne Warteplätze die Prozesse der von diesem System abgewiesenen Kunden bzw. nach erfolgtem Service ausgeschiedenen Kunden im Hinblick auf ihre Verwendung als Eingangsprozesse für weitere Servicesysteme zu charakterisieren.Für beide Prozesse ist es gelungen, die Anzahl der in einem beliebigen Zeitintervall abgewiesenen bzw. ausgeschiedenen Kunden durch Wahrscheinlichkeitsgesetze zu beschreiben. Darüber hinaus konnten notwendige und hinreichende Bedingungen angegeben werden, wann der Prozeß der ausgeschiedenen Kunden wieder die EigenschaftGI besitzt.
Diese Untersuchung wurde im Rahmen eines von Herrn Prof. Dr.H. Söhngen geleiteten Forschungsauftrags des BMVtdg durchgeführt.
Vorgel. v.:H. Söhngen. 相似文献
Summary The purpose of this investigation is, to describe in case of aGI |G|1) — servicesystem without waiting-room the processes of clients refused by this system respectively cast out after having finished service with regard to their applying as input-processes of any other servicesystem.It has been achieved for both processes to set up the probability laws of the number of clients refused respectively cast out during any interval of time.Beyond these results the author has quoted necessary and sufficient conditions for the process of clients cast out to possess the propertyGI.
Diese Untersuchung wurde im Rahmen eines von Herrn Prof. Dr.H. Söhngen geleiteten Forschungsauftrags des BMVtdg durchgeführt.
Vorgel. v.:H. Söhngen. 相似文献
123.
Nargiz B. Asanbaeva Larisa Yu. Gurskaya Yuliya F. Polienko Tatyana V. Rybalova Maxim S. Kazantsev Alexey A. Dmitriev Nina P. Gritsan Nadia Haro-Mares Torsten Gutmann Gerd Buntkowsky Evgeny V. Tretyakov Elena G. Bagryanskaya 《Molecules (Basel, Switzerland)》2022,27(10)
Spiro-substituted nitroxyl biradicals are widely used as reagents for dynamic nuclear polarization (DNP), which is especially important for biopolymer research. The main criterion for their applicability as polarizing agents is the value of the spin–spin exchange interaction parameter (J), which can vary considerably when different couplers are employed that link the radical moieties. This paper describes a study on biradicals, with a ferrocene-1,1′-diyl-substituted 1,3-diazetidine-2,4-diimine coupler, that have never been used before as DNP agents. We observed a substantial difference in the temperature dependence between Electron Paramagnetic Resonance (EPR) spectra of biradicals carrying either methyl or spirocyclohexane substituents and explain the difference using Density Functional Theory (DFT) calculation results. It was shown that the replacement of methyl groups by spirocycles near the N-O group leads to an increase in the contribution of conformers having J ≈ 0. The DNP gain observed for the biradicals with methyl substituents is three times higher than that for the spiro-substituted nitroxyl biradicals and is inversely proportional to the contribution of biradicals manifesting the negligible exchange interaction. The effects of nucleophiles and substituents in the nitroxide biradicals on the ring-opening reaction of 1,3-diazetidine and the influence of the ring opening on the exchange interaction were also investigated. It was found that in contrast to the methyl-substituted nitroxide biradical (where we observed the ring-opening reaction upon the addition of amines), the ring opening does not occur in the spiro-substituted biradical owing to a steric barrier created by the bulky cyclohexyl substituents. 相似文献
124.
Ternary Halides of the A3MX6 Type. VIII On the Crystal Structure of Li3InCl6 Colorless single crystals of Li3InCl6 are obtained from a 3 : 1 molar mixture of LiCl and InCl3 via Bridgman‐type crystal growth. The crystal structure (monoclinic, C2/m, Z = 2, a = 643.2(3), b = 1109.3(3), c = 639.8(3) pm, β = 109.8(1)° R1 = 0.0549, wR2 = 0.1364 (all data) may be derived from the AlCl3‐type of structure as was previously also found for the bromides Li3MBr6 (M = Sm–Lu, Y) and iodides Li3MI6 (M = Er–Yb, Y). 相似文献
125.
126.
Ulrich Wannagat Hans Bürger Peter Geymayer Gerd Torper 《Monatshefte für Chemie / Chemical Monthly》1964,95(1):39-45
Zusammenfassung Gemischt substituierte Disilylamine (RRRSi)2NH lassen sich von NaNH2 zu reaktionsfähigen Natrium-bis-(silyl)-amiden metallieren, aus denen nach Umsetzung mit Organohalogensilanen und anschließender Alkoholyse der verbleibenden Si-Cl-Gruppen gemischt substituierte Trisilylamine (RRRSi)3N mit R=(me), R, R=O(me); R,R=(me), R=O(et); R=(vi), R, R=O(me); R=(me), R=(vi), R=O(ipr) dargestellt werden konnten.33. Mitt.:U. Wannagat, J. Pump undH. Bürger, Mh. Chem.94, 1013 (1963).Auszüge aus den DissertationenH. Bürger, TH Aachen 1962,P. Geymayer, TH Graz 1963, und der DiplomarbeitG. Torper, TH Graz 1962; vgl. auchU. Wannagat undH. Bürger, Angew. Chem.75, 95 (1963). 相似文献
127.
128.
We report lifetime measurements of the 1s 2 3d 2 D, 1s 24d 2 D, and 1s 22p 2 P states of lithium. The results τ=14.5±0.7 ns, τ=31.0±1.0 ns, and τ=27.9±1.0 ns respectively were obtained by time resolved detection of the resonance fluorescence following pulsed laser excitation. 相似文献
129.
Isotypic Borophosphates MII(C2H10N2)[B2P3O12(OH)] (MII = Mg, Mn, Fe, Ni, Cu, Zn): Compounds containing Tetrahedral Layers The isotypic compounds MII(C2H10N2) · [B2P3O12(OH)] (MII = Mg, Mn, Fe, Ni, Cu, Zn) were prepared under hydrothermal conditions (T = 170 °C) from mixtures of the metal chloride (chloride hydrate, resp.), Ethylenediamine, H3BO3 and H3PO4. The orthorhombic crystal structures (Pbca, No. 61, Z = 8) were determined by X‐ray single crystal methods (Mg(C2H10N2)[B2P3O12(OH)]: a = 936.81(2) pm, b = 1221.86(3) pm, c = 2089.28(5) pm) and Rietveld‐methods (MII = Mn: a = 931.91(4) pm, b = 1234.26(4) pm, c = 2129.75(7) pm, Fe: a = 935.1(3) pm, b = 1224.8(3) pm, c = 2088.0(6) pm, Ni: a = 939.99(3) pm, b = 1221.29(3) pm, c = 2074.05(7) pm, Cu: a = 941.38(3) pm, b = 1198.02(3) pm, c = 2110.01(6) pm, Zn: a = 935.06(2) pm, b = 1221.33(2) pm, c = 2094.39(4) pm), respectively. The anionic part of the structure contains tetrahedral layers, consisting of three‐ and nine‐membered rings. The MII‐ions are in a distorted octahedral or tetragonal‐bipyramidal [4 + 2] (copper) coordination formed by oxygen functions of the tetrahedral layers. The resulting three‐dimensional structure contains channels running along [010]. Protonated Ethylenediamine ions are fixed within the channels by hydrogen bonds. 相似文献
130.
The anhydrous rubidium tetraacetato lanthanate, RbLa(CH3COO)4, is obtained together with Rb2La(CH3COO)5(H2O) as colourless single crystals from a 1 : 2 mixture of Rb2CO3 and La(CH3COO) · 1.5 H2O in acetic acid by slow evaporation. The crystal structure [orthorhombic, Pnnm, Z = 2, a = 1242.0(3), b = 1650.1(4), c = 698.0(4) pm, R = 0.028, Rw = 0.071] contains La3+ nine coordinate by oxygen atoms of six acetate ligands. The polyhedra are connected to dimers and further to double chains running parallel to [001]. These [La(CH3COO)4]– double chains are surrounded by four like double chains and connected by Rb+ ions that are seven coordinate by oxygen atoms. 相似文献