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991.
A novel series of pyrene derivatives 3-6 functionalized with different aromatic substituents at 2,7-positions of the pyrene core have been readily synthesized by Suzuki coupling reactions. Single crystals suitable for X-ray crystallographic analysis of compounds 3-6 were all successfully obtained. The optical, electrochemical, and thermal properties of these newly synthesized compounds were thoroughly investigated and discussed. Theoretical calculation was adopted to study the geometric and electronic structure of compounds 3-6. Additionally, preliminary studies demonstrated that field-effect transistors using compound 3, 5, and 6 performed as p-type semiconductors, in which a field-effect mobility as high as 0.018 cm2 V−1 s−1 and current on/off ratio of 106 were achieved from compound 6. 相似文献
992.
Three lanthanum/4-sulfocalix[4]arene complexes,namely,H2[(H4CAS)La(H2O)7]2· H2[(H4CAS)La(H2O)7]2·2C2H5OH·12H2O(1),[H(H4CAS)La(H2O)5]·5H2O(2)and [(H4CAS)La-(H2O)4(NO3)La(H2O)5]·7H2O(3),have been synthesized at different pH conditions.Complex 1,which exhibits the structure of "molecular capsule" containing the guest of C2H5OH molecule,is formed at pH = 1.At pH = 2~3,a two-dimensional(2D)coordination polymer of 2 is formed.Further increase of the pH value to 5 leads to the three-dimensional(3D)coordination polymer of 3.Crystal data for 1:monoclinic,space group P21/n,a = 10.8743(16),b = 25.957(4),c = 15.863(2),β = 94.763(2)°,V = 4462.1(11)3,Mr = 1160.87,Z = 4,F(000)= 2376,R = 0.0370 and wR = 0.0936;Crystal data for 2:tetragonal,space group P4/n,a = 11.6593(16),c = 14.069(4),V = 1912.5(6)3,Mr = 1114.81,Z = 2,F(000)= 1136,R = 0.0849 and wR = 0.1906;and those for 3:triclinic,space group P1,a = 10.4588(16),b = 14.995(2),c = 16.699(3),α = 65.446(3),β = 83.487(3),γ = 73.305(3)°,V = 2281.6(6)3,Mr = 1367.76,Z = 2,F(000)= 1368,R = 0.0423 and wR = 0.1183. 相似文献
993.
Anastasia N. GeorgopoulouConstantinos G. Efthymiou Constantina PapatriantafyllopoulouVassilis Psycharis Catherine P. RaptopoulouManolis Manos Anastasios J. TasiopoulosAlbert Escuer Spyros P. Perlepes 《Polyhedron》2011,30(18):2978-2986
The synthetic investigation of the NiII/M(NO3)3·6H2O/di-2-pyridyl ketone [(py)2CO] tertiary reaction system in EtOH has yielded triangular Ni2M cationic complexes (M = lanthanide, Y). The reaction between Ln(NO3)3·6H2O, Ni(ClO4)2·6H2O, (py)2CO and base (1:3:3:3) in EtOH under gentle heating gave the isostructural complexes [Ni2Ln{(py)2C(OEt)(O)}3{(py)2C(OH)(O)}(NO3)(H2O)](ClO4)2 (Ln = Gd, 2; Ln = Tb, 3) in high yields. The ligands (py)2C(OEt)(O)− and (py)2C(OH)(O)− are the monoanions of the hemiketal and gem-diol derivatives of (py)2CO, respectively, formed in situ in the presence of the metal ions. The cations of 2 and 3 consist of one 8-coordinate LnIII and two distorted octahedral NiII atoms in an essentially isosceles, triangular arrangement capped by a central μ3-Ο− atom of the unique 3.3011 (Harris notation) (py)2C(OH)(O)− ligand. Each metal-metal edge is bridged by the deprotonated O atom of one 2.2011 (py)2C(OEt)(O)− ligand. The isostructural complexes [Ni2M{(py)2C(OEt)(O)}4(NO3)(H2O)]2[M(NO3)5](ClO4)2 (M = Y, 4 ; M = Tb, 5 ; M = Dy, 6) were prepared by the 1:1 reaction of the mononuclear “metalloligand” [Ni(O2CMe){(py)2CO}{(py)2C(OH)2}](ClO4) (1) and M(NO3)3·6H2O in EtOH under mild heating in moderate to good yields. The structures of the dications of 4-6 are similar to those in 2 and 3, the only difference being the replacement of the unique 3.3011 (py)2C(OH)(O)− ligand of the latter by one 3.3011 (py)2C(OEt)(O)− group in the former. The YIII, TbIII and DyIII atoms in [M(NO3)5]2− are coordinated by five bidentate chelating nitrato groups. Characteristic IR bands of the complexes are discussed in terms of the known structures and the coordination modes of the ligands. Variable temperature, solid-state direct current magnetic susceptibility and magnetization studies were carried out on dried samples of 2-4. The data indicate ferromagnetic Ni?Ni and Ni?Gd exchange interactions, and an ST = 11/2 ground state for 2. Complex 3 is characterized by a high-spin ground state while the ferromagnetic Ni?Ni interaction for 2 is independently supported by the study of 4. No out-of-phase, alternating current susceptibility signals have been detected for 3 that would be indicative of SMM behavior. 相似文献
994.
Rafael Bou-MorenoSimon A. Cotton Verity HunterKathryn Leonard Andrew W.G. PlattPaul R. Raithby Stefanie Schiffers 《Polyhedron》2011,30(17):2832-2836
The new cobalt(II) phosphine oxide complexes Co(Cy3PO)2Cl2 (1), Co(Cy3PO)2Br2 (2), Co(Cy3PO)2I2 (3), Co(Ph2CyPO)2Cl2 (4), Co(Ph2CyPO)2Br2 (5), Co(Ph2CyPO)2I2 (6), Co(Ph2EtPO)2Br2 (7), Co(Cy3PO)2(NCS)2 (8) and Co(Cy3PO)2(NO3)2 (9) have been prepared mainly by the reaction of anhydrous CoX2 (X = Cl, Br, I, NCS, NO3) with the appropriate phosphine oxide. The complexes were characterised by single-crystal X-ray crystallography supported by IR and UV-Vis absorption spectroscopy. The structural analyses show that the cobalt(II) centre adopts a distorted tetrahedral coordination geometry except for 9 which displays an octahedral geometry. Systematic structural features of these complexes are explained within this paper. 相似文献
995.
996.
Gabrieli L. ParrilhaAuthor VitaeRafael P. VieiraAuthor Vitae Anayive P. RebolledoAuthor VitaeIsolda C. MendesAuthor Vitae Lidia M. LimaAuthor VitaeEliezer J. BarreiroAuthor Vitae Oscar E. PiroAuthor VitaeEduardo E. CastellanoAuthor Vitae Heloisa BeraldoAuthor Vitae 《Polyhedron》2011,30(11):1891-1898
Complexes [Zn2(HL1)2(CH3COO)2] (1) and [Zn2(L2)2] (2) were synthesized with salicylaldehyde semicarbazone (H2L1) and salicylaldehyde-4-chlorobenzoyl hydrazone (H2LASSBio-1064, H2L2), respectively. The crystal structure of (1) was determined. Upon recrystallization of previously prepared [Zn2(HL2)2(Cl)2] (3) in 1:9 DMSO:acetone crystals of [Zn2(L2)2(H2O)2]·[Zn2(L2)2(DMSO)4] (3a) were obtained. The crystal structure of 3a was also determined. All crystal structures revealed the presence of phenoxo-bridged binuclear zinc(II) complexes. 相似文献
997.
Ferrando-Soria J Pardo E Ruiz-García R Cano J Lloret F Julve M Journaux Y Pasán J Ruiz-Pérez C 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(7):2176-2188
A series of neutral oxamato‐bridged heterobimetallic chains of general formula [MCu(Lx)2(S)2] ? p S ? q H2O [p=0–1, q=0–2.5; L1=N‐2,6‐dimethylphenyloxamate, S=DMF with M=Mn ( 1 a ) and Co ( 1 b ); L2=N‐2,6‐diethylphenyloxamate, S=DMF with M=Mn ( 2 a ) and Co ( 2 b ) or S=DMSO with M=Mn ( 2 c ) and Co ( 2 d ); L3=N‐2,6‐diisopropylphenyloxamate, S=DMF with M=Mn ( 3 a ) and Co ( 3 b ) or S=DMSO with M=Mn ( 3 c ) and Co ( 3 d )] were prepared by treating the corresponding anionic oxamatocopper(II) complexes [Cu(Lx)2]2? (x=1–3) with M2+ cations (M=Mn and Co) in DMF or DMSO as the solvent. The single‐crystal X‐ray structures of 2 a and 3 a reveal the occurrence of well‐isolated, zigzag, oxamato‐bridged manganese(II)–copper(II) chains. The intrachain Cu ??? Mn distances across the oxamato bridge are 5.3761(7) and 5.4002(17) Å for 2 a and 3 a , respectively, whereas the shortest interchain Mn ??? Mn distances are 9.4475(16) and 8.1649(14) Å for 2 a and 3 a , respectively. All of these MIICuII chains (M=Mn and Co) exhibit 1D ferrimagnetic behaviour with moderately strong intrachain antiferromagnetic coupling between the square‐planar CuII and octahedral high‐spin MII ions across the oxamato bridge [?J=31.4–35.2 and 33.4–44.8 cm?1, respectively; H =∑i?J S M,i( S Cu,i+ S Cu,i?1)]. Only the CoIICuII chains show slow magnetic relaxation effects characteristic of single‐chain magnets (SCMs). Analysis of the magnetic relaxation dynamics of 3 d shows a thermally activated mechanism (Arrhenius law dependence) with values of the pre‐exponential factor (τ0=2.6×10?9 s) and activation energy (Ea=7.7 cm?1) that are typical of SCMs. In contrast, two relaxation regimes are observed for 2 d in different temperature regions (τ0=3.2×10?10 s and Ea=24.7 cm?1 for T<4.5 K and τ0=3.2×10?14 s and Ea=37.5 cm?1 for T>4.5 K). 相似文献
998.
Greer BJ Michaelis VK Katz MJ Leznoff DB Schreckenbach G Kroeker S 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(13):3609-3618
A series of lead(II) coordination polymers containing [N(CN)2]? (DCA) or [Au(CN)2]? bridging ligands and substituted terpyridine (terpy) ancillary ligands ([Pb(DCA)2] ( 1 ), [Pb(terpy)(DCA)2] ( 2 ), [Pb(terpy){Au(CN)2}2] ( 3 ), [Pb(4′‐chloro‐terpy){Au(CN)2}2] ( 4 ) and [Pb(4′‐bromo‐terpy)(μ‐OH2)0.5{Au(CN)2}2] ( 5 )) was spectroscopically examined by solid‐state 207Pb MAS NMR spectroscopy in order to characterise the structural and electronic changes associated with lead(II) lone‐pair activity. Two new compounds, 2 and [Pb(4′‐hydroxy‐terpy){Au(CN)2}2] ( 6 ), were prepared and structurally characterised. The series displays contrasting coordination environments, bridging ligands with differing basicities and structural and electronic effects that occur with various substitutions on the terpyridine ligand (for the [Au(CN)2]? polymers). 207Pb NMR spectra show an increase in both isotropic chemical shift and span (Ω) with increasing ligand basicity (from δiso=?3090 ppm and Ω=389 ppm for 1 (the least basic) to δiso=?1553 ppm and Ω=2238 ppm for 3 (the most basic)). The trends observed in 207Pb NMR data correlate with the coordination sphere anisotropy through comparison and quantification of the Pb? N bond lengths about the lead centre. Density functional theory calculations confirm that the more basic ligands result in greater p‐orbital character and show a strong correlation to the 207Pb NMR chemical shift parameters. Preliminary trends suggest that 207Pb NMR chemical shift anisotropy relates to the measured birefringence, given the established correlations with structure and lone‐pair activity. 相似文献
999.
Wang C Pu F Lin Y Ren J Dohn C Nakatani K Qu X 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(29):8189-8194
A robust and photoresponsive DNA network has been designed and constructed from branched DNA and molecular glue. The molecular glue is photoswitchable and can specifically bind to G-G mismatched double-stranded DNA. The assembly process can be reversibly controlled by manipulating the wavelength of light. The approach is flexible, allowing tuning of the size, morphology as well as the cavity of the network by variation of the molar ratio and the isotropic/anisotropic character of the branched building blocks. The assembled architectures are versatile and heat tolerant. These properties should allow the use of the network in further applications. 相似文献
1000.
Liu Y Son WJ Lu J Huang B Dai Y Whangbo MH 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(34):9342-9349
We prepared BiOCl(1-x)Br(x) (x=0-1) solid solutions and characterized their structures, morphologies, and photocatalytic properties by X-ray diffraction, diffuse reflectance spectroscopy, scanning electron microscopy, Raman spectroscopy, photocurrent and photocatalytic activity measurements and also by density functional theory calculations for BiOCl, BiOBr, BiOCl(0.5)Br(0.5). Under visible-light irradiation BiOCl(1-x)Br(x) exhibits a stronger photocatalytic activity than do BiOCl and BiOBr, with the activity reaching the maximum at x=0.5 and decreasing gradually as x is increased toward 1 or decreased toward 0. This trend is closely mimicked by the photogenerated current of BiOCl(1-x)Br(x) , indicating that the enhanced photocatalytic activity of BiOCl(1-x)Br(x) with respect to those of BiOCl and BiOBr originates from the trapping of photogenerated carriers. Our electronic structure calculations for BiOCl(0.5)Br(0.5) with the anion (O(2-), Cl(-), Br(-)) and cation (Bi(3+)) vacancies suggest that the trapping of photogenerated carriers is caused most likely by Bi(3+) cation vacancies, which generate hole states above the conduction band maximum. 相似文献