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41.
42.
Chemistry of Diruthenium and Dirhodium Analogues of Pentaborane(9): Synthesis and Characterization of Metal N,S‐Heterocyclic Carbene and B‐Agostic Complexes 下载免费PDF全文
M. Sc. Dipak Kumar Roy M. Sc. Bijan Mondal M. Sc. R. S. Anju Prof. Sundargopal Ghosh 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(9):3640-3648
Building upon our earlier results on the synthesis of electron‐precise transition‐metal–boron complexes, we continue to investigate the reactivity of pentaborane(9) and tetraborane(10) analogues of ruthenium and rhodium towards thiazolyl and oxazolyl ligands. Thus, mild thermolysis of nido‐[(Cp*RuH)2B3H7] ( 1 ) with 2‐mercaptobenzothiazole (2‐mbtz) and 2‐mercaptobenzoxazole (2‐mboz) led to the isolation of Cp*‐based (Cp*=η5‐C5Me5) borate complexes 5 a , b [Cp*RuBH3L] ( 5 a : L=C7H4NS2; 5 b : L=C7H4NOS)) and agostic complexes 7 a , b [Cp*RuBH2(L)2], ( 7 a : L=C7H4NS2; 7 b : L=C7H4NOS). In a similar fashion, a rhodium analogue of pentaborane(9), nido‐[(Cp*Rh)2B3H7] ( 2 ) yielded rhodaboratrane [Cp*RhBH(L)2], 10 (L=C7H4NS2). Interestingly, when the reaction was performed with an excess of 2‐mbtz, it led to the formation of the first structurally characterized N,S‐heterocyclic rhodium‐carbene complex [(Cp*Rh)(L2)(1‐benzothiazol‐2‐ylidene)] ( 11 ) (L=C7H4NS2). Furthermore, to evaluate the scope of this new route, we extended this chemistry towards the diruthenium analogue of tetraborane(10), arachno‐[(Cp*RuCO)2B2H6] ( 3 ), in which the metal center possesses different ancillary ligands. 相似文献
43.
AbstractWe introduce diffeological algebraic hyperstructures such as diffeological hypergroups and diffeological polygroups, which are generalizations of diffeological groups. After providing some examples of these notions, we investigate the relationships between diffeological hypergroups and diffeological groups. It is proved that there is an equivalence of categories between subductions over diffeological groups and diffeological complete hypergroups. We finally show how every diffeological polygroup is a subpolygroup of a diffeological poly-monoid of hyper-diffeomorphisms.Communicated by J. L. Gomez Pardo 相似文献
44.
Anuradha Lahiri Prodyot Kumar Roy Bijan Bagchi 《International Journal of Theoretical Physics》1989,28(2):183-189
Using the ladder operator technique, a construction of the supersymmetric Hamiltonian is proposed. We show that the accidental degeneracies associated with the Coulomb and isotropic oscillator problems may be attributed to the existence of a supersymmetry of the Hamiltonians. 相似文献
45.
Bijan Etemadi Abdol Abadi Rex A. Palmer Brian W. Fitzsimmons 《Journal of chemical crystallography》1988,18(1):35-53
The crystal structure of bis (NN-di(n-propyl)dithiocarbamato iron(III) iodide, FeIII(S2CN6H14)2I, has been determined by the heavy-atom method and refined toR=0.055 for 3487 reflections withI(hkl)>3I(hkl). The crystals are triclinic,C¯1,Z=8,a=27.644(6),b=19.186(4),c=8.694(2) Å,=87.79(1),=88.72(1), =101.87(2)°. The I-Fe bond lengths are different in the two moleculesA andB in the asymmetric unit, having values of 2.642 Å (2.655) and 2.612 Å (2.634) respectively (libration-corrected values given in parentheses). The measured effective magnetic moment
eff3.89 BM, independent of temperature (93-353K), suggests a spinS of 3/2 with three unpaired electrons for FeIII. 相似文献
46.
Precise measurements of the electrical conductances of solutions of potassium thiocyanate (KCNS), ammonium thiocyanate (NH4CNS), sodium nitrate (NaNO3) and ammonium nitrate (NH4NO3) in 2-ethoxyethanol (EE) at temperatures 35, 40, 45 and 50,∘C are reported. The conductance data have been analyzed by the 1978 Fuoss conductance equation. A thermodynamic analysis of the ionic association processes has also been made and the Coulombic forces are found to play a major role in the association processes. The ionic contributions to the limiting equivalent conductances have been determined using the reference electrolyte method. Strong association was found for all these electrolytes in this solvent medium. The cations are found to be substantially solvated in 2-ethoxyethanol, whereas the anions appear to have only weak interaction with the solvent molecules. 相似文献
47.
John Koenitzer Bijan Khazai Jacob Hormadaly Robert Kershaw Kirby Dwight Aaron Wold 《Journal of solid state chemistry》1980,32(1):128-129
The orthorhombic α-PbO2 phase of FeNbO4 was prepared and its photoelectronic properties measured: Sintered disks were shown to be n type and gave a resistivity of 40 Ω-cm. Measurements of the photoresponse gave a flat-band potential between 0.1 and 0.4 V vs SCE at a pH of 8.5 and an optical band gap of 2.08(2) eV. Several higher-energy band gaps at 2.68(2), 2.94(2), 3.24(2), and 4.38(2) eV were also determined. There appears to be an enhancement of the quantum efficiency due to the presence of [FeO6] active centers while retaining the fundamental characteristics of the [NbO6] octahedra. 相似文献
48.
Summary A group of mixed-tris chelates of osmium(III) and osmium(IV) of type [OsAQ2]0/1 + [HA = glycine (glyH), picolinic acid (PicH) and quinaldic acid (qndH); HQ = 8-quinolinol] were prepared and characterized by physicochemical, magnetic and spectroscopic methods. The complexes exhibit several spin-allowed and spin-forbidden absorption bands and shoulders in the 200–700 nm region. The new chelates are electroactive and display nearly reversible OsIV-OsIII and OsIII-OsII couples in the ca. –1.1 to +0.3 V range versus s.c.e. The stability of metal oxidation states is discussed in terms of the electrochemical results. 相似文献
49.
50.
Optics is regarded undoubtedly a potential and successful candidate in information and data processing because of its inherent
parallelism. In last few decades several all-optical data processors, algebraic processors, arithmetic processors are proposed.
Here in this communication the authors propose a completely new scheme for implementing binary data arithmetic in 2’s Complement
method which is the most advantageous among all other established subtraction methods. To implement it we use non-linear material
massively. 相似文献