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721.
Güne? Süheyla Kürk?üo?lu Okan Zafer Ye?ilel ?lkan Kavlak Orhan Büyükgüng?r 《Structural chemistry》2008,19(6):879-888
Polymeric tetracyanonickelate complexes of the type [M(H2O)(2mpz)Ni(μ-CN)4]
n
(2mpz = 2-methylpyrazine, M = Mn(II) (1) or Cd(II) (2)) have been prepared and characterized by FT-IR, Raman spectroscopy, thermal, and elemental analyses. The crystal structure
of supramolecular [Cd(H2O)(2mpz)Ni(CN)4]
n
complex has been determined by X-ray single crystal diffraction. It crystallizes in the orthorhombic system, space group
Pnma. The structure consists of corrugated and cyanide-bridged polymeric two-dimensional networks. In the Hofmann-type complexes,
the coordination environment of the M(II) ions can be described as distorted octahedral geometry, whereas around the Ni(II)
center has square planar geometry. The spectral features suggest that the 2mpz is coordinated to metal ions of the adjacent
layers of [M-Ni(CN)4]
n
as monodentate ligand. The thermal decomposition of these complexes takes place in three stages: (i) dehydration, (ii) decomposition
of the 2-methylpyrazine ligands, and (iii) release of the CN groups and burning of organic residue. 相似文献
722.
Nazan Ocak İskeleli Hasan Karabıyık Çiğdem Albayrak Erbil Ağar İsmail Erdem Gümrükçüoğlu 《Structural chemistry》2008,19(4):565-570
The molecular and crystal structures of the title compound, C16H18N2O, were characterized and determined by single crystal X-ray diffraction method in addition to spectroscopic means such as IR, UV–VIS and 1H NMR. The compound crystallizes in orthorhombic space group P bca, with a = 9.3350(5) Å, b = 23.4878(13) Å, c = 26.5871(12) Å, Z = 16, D calc. = 1.1591(1) g/cm3, μ (MoKα) = 0.073 mm?1. Monomers of the compound in the crystal structure are linked into C(7) and C(8) chains generated by translation along the [1 0 0] direction with the aid of O–H···N type H-bonds which serve to the stabilization of periodic organization of the molecules beside major and minor component in the disordered azo fragment. In order to describe conformational flexibility and the crystal packing effects on the molecular conformation, potential barriers regarding the rotation along both Ar–N bonds were calculated by varying the related torsional degrees of freedom in every 10° ranging from ?180° to +180° via quantum chemical calculations at DFT/B3LYP level. 相似文献
723.
Albayrak C Odabaşoğlu M Ozek A Büyükgüngör O 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2012,85(1):85-91
In this study, the molecular structure and spectroscopic properties of the title compound were characterized by X-ray diffraction, FT-IR and UV-vis spectroscopies. These properties were also investigated using DFT method. The most convenient conformation of title compound was firstly determined. The geometry optimizations in gas phase and solvent media were performed by DFT methods with B3LYP adding 6-31G(d) basis set. The differences between crystal and computational structures are due to crystal packing in which hydrogen bonds play an important role. UV-vis spectra were recorded in different organic solvents. The results show that title compound exists in both keto and enol forms in DMSO, EtOH but it tends to shift towards enol form in benzene. The polar solvents facilitate the proton transfer by decreasing the activation energy needed for Transition State. The formation of both keto and enol forms in DMSO and EtOH is due to decrease in the activation energy. TD-DFT calculations starting from optimized geometry were carried out in both gas and solution phases to calculate excitation energies of the title compound. The non-linear optical properties were computed at the theory level and the title compound showed a good second order non-linear optical property. In addition, thermodynamic properties were obtained in the range of 100-500K. 相似文献
724.
725.
By using 2'-hydroxyacetophenoxime, a new family of complexes with an [Mn(III)(2)Mn(IV)(3)Ln(5)O(5)] core was obtained with Ln = Tm (1), Lu (2), and Yb (3). Heterometallic Mn/Tm and Mn/Lu combinations have had no precedence so far. Studies of the magnetic properties indicate the presence of intracomplex antiferromagnetic interactions in 1 and 3, as well as a dominating ferromagnetic interaction between Mn(III) and Mn(IV) spins in 2, leading to an S(T) = 5/2 ground state. 相似文献
726.
A double‐decker (DD) type selenidogermanate complex with C=O functionalized organic decoration, [(R1Ge4)Se6] ( 1 , R1 = CMe2CH2COMe), was synthesized by reaction of R1GeCl3 with Na2Se, and subsequently underwent a light‐induced transformation reaction to yield [Na(thf)2][(RGeIV)2(RGeIII)(GeIIISe)Se5] ( 2 ). Similar to the observations reported previously for the Sn/S homologue of 1 , the product comprises a mixed‐valence complex with a newly formed Ge–Ge bond. However, different from the transformation of the tin sulfide complex, the selenidogermanate precursor did not produce a paddle‐wheel‐like dimer of the DD type structure, but led to the formation of a noradamantane (NA) type architecture, which has so far been restricted to the Si/Se and Ge/Te elemental combination. 相似文献
727.
Back BB Baker MD Ballintijn M Barton DS Betts RR Bickley AA Bindel R Budzanowski A Busza W Carroll A Chai Z Decowski MP García E Gburek T George N Gulbrandsen K Gushue S Halliwell C Hamblen J Hauer M Heintzelman GA Henderson C Hofman DJ Hollis RS Hołyński R Holzman B Iordanova A Johnson E Kane JL Katzy J Khan N Kucewicz W Kulinich P Kuo CM Lin WT Manly S McLeod D Mignerey AC Nouicer R Olszewski A Pak R Park IC Pernegger H Reed C Remsberg LP Reuter M Roland C Roland G Rosenberg L Sagerer J 《Physical review letters》2006,97(1):012301
We report on measurements of directed flow as a function of pseudorapidity in Au + Au collisions at energies of square root of SNN = 19.6, 62.4, 130 and 200 GeV as measured by the PHOBOS detector at the BNL Relativistic Heavy Ion Collider. These results are particularly valuable because of the extensive, continuous pseudorapidity coverage of the PHOBOS detector. There is no significant indication of structure near midrapidity and the data surprisingly exhibit extended longitudinal scaling similar to that seen for elliptic flow and charged particle pseudorapidity density. 相似文献
728.
The valuable new synthetic intermediates, ethyl 4‐, 6‐ and 7‐formyl‐1H‐indole‐2‐carboxylates ( 10, 11, 12 ) were prepared from 2‐ethoxycarbonyl‐1H‐indole‐4‐, 6‐ and 7‐methanesulfonic acids ( 1, 2, 3 ), respectively. The transformation of sulfomethyl group to formyl function was accomplished through elimination of SO2 to yield ethyl 4‐, 6‐ and 7‐chloromethyl‐1H‐indole‐2‐carboxylates ( 4, 5, 6 ), hydrolysed to ethyl 4‐, 6‐ and 7‐hydroxymethyl‐1H‐indole‐2‐carboxylates ( 7, 8, 9 ), then oxidized to aldehydes ( 10, 11, 12 ). Protection at N1 of indole was not necessary. A marked increase in the rate of hydrolysis of 7‐chloromethyl‐indoles compared to that of 4‐ and 6‐(chloromethyl)indoles was observed. 相似文献
729.
Figen Arslan Assoc. Prof. Dr. Halis Ölmez Mustafa Odabaşoğlu Orhan Büyükgüngör 《无机化学与普通化学杂志》2010,636(8):1641-1644
µ‐2,2′‐Azobispyridinebis[2,2′‐azobispyridinesalicylato(O)salicylato(O,O′) cadmium(II)], (µ‐abpy)[Cd(Hsal)2(abpy)]2 ( I ) was synthesized and characterized by IR and UV/ Vis spectroscopy, thermal analysis, and X‐ray diffraction techniques. Two abpy ligands and two salicylato ligands coordinate to the Cd2+ ion in a monocapped trigonal‐prismatic arrangement. The capping atom is the N3 atom. One of the two abpy ligands behaves as a “s‐frame” bridging ligand and adopts a s‐cis/ E/ s‐cis conformation, whereas the other one adopts as a s‐cis/ E/ s‐trans conformation. One of the two salicylato ligands acts as a monodentate ligand, which coordinates with the carboxylate oxygen atom, whereas the other one adopts bidentate coordination through two carboxylate oxygen atoms. The hydroxy groups of salicylato ligands, which coordinate in a monodentate fashion, are disordered over two positions, with occupancies of 0.52 for group A and 0.48 for group B. The decomposition reaction takes place in the temperature range 20–1000 °C under nitrogen. Thermal decomposition of the title complex proceeds in two stages. 相似文献
730.
M. K. Pham M. Betti P. P. Povinec M. Benmansour R. Bojanowski P. Bouisset E. C. Calvo G. J. Ham E. Holm M. Hult C. Ilchmann M. Kloster G. Kanisch M. Köhler J. La Rosa F. Legarda M. Llauradó A. Nourredine J.-S. Oh M. Pellicciari U. Rieth A. M. Rodriguez y Baena J. A. Sanchez-Cabeza H. Satake J. Schikowski M. Takeishi H. Thébault Z. Varga 《Journal of Radioanalytical and Nuclear Chemistry》2010,283(3):851-859
A new Reference Material (RM) for radionuclides in mussel (Mytilus galloprovincialis) from the Mediterranean Sea (IAEA-437) is described and the results of the certification process are presented. Four radionuclides (40K, 234U, 238U, and 239+240Pu) have been certified, and information values on massic activities with 95% confidence intervals are given for nine radionuclides (137Cs, 210Pb(210Po), 226Ra, 228Ra, 228Th, 230Th, 232Th, 235U, and 241Am). Results for less frequently reported radionuclides (90Sr, 129I, 238Pu, 239Pu, and 240Pu) are also reported. The RM can be used for quality assurance/quality control of the analysis of radionuclides in mussel samples, for the development and validation of analytical methods and for training purposes. The material is available in 200 g units. 相似文献