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991.
Sarah Angus‐Dunne Prof. Dr. Robert C. Burns Donald C. Craig Geoffrey A. Lawrance 《无机化学与普通化学杂志》2010,636(5):727-734
The first example of a heteropolyoxomolybdate containing palladium(IV) was isolated and characterized by X‐ray crystallography. The palladium(IV) hexamolybdate, K0.75Na3.75[PdMo6O24H3.5]·17H2O, was isolated from an aqueous solution at pH 4.5 in the space group P\bar{1} , a 10.790(2), b 12.244(3), c 14.086(3) Å, α 113.77(1), β 90.41(1),γ 107.86(1)°, and the structure was determined using X‐ray diffraction methods, refining to a residual of 0.0301 for 5334 reflections. A formal “[PdMo6O24H3]5–” subunit exhibits the basic Anderson structure, with two [PdMo6O24H3]5– cluster anions in the structure bridged by a hydrogen atom (formally an H+) situated on a center of symmetry to give a “[Pd2Mo12O48H7]9–” dimeric anion. The palladium(IV) atom occupies a slightly distorted octahedral environment, with Pd–O distances ranging from 1.968 to 2.009 Å. 相似文献
992.
Jie Yang Dunru Zhu Prof. Dr. Haijuan Zhang Yan Xu Lei Shen Xiaozhu Wang Rongxin Yuan 《无机化学与普通化学杂志》2010,636(6):1129-1132
A novel metal‐organic framework, [Zn(C10H8O5)]n ( 1 ) (C10H8O5 = 2‐(4‐carboxylatophenoxy)propionate), was synthesized and characterized by elemental analysis, IR spectroscopy, X‐ray crystallography and thermogravimetric analysis. The crystal structure study reveals that each zinc atom is coordinated by four oxygen atoms from four different ligands to obtain a distorted tetrahedron. The rigid carboxyl group bridges two adjacent zinc atoms to form a dimer of eight‐membered rings, whereas the flexible carboxyl group bridges two adjacent dimers to form 1D chains along the a axis. Two adjacent 1D chains are interconnected by the ligands to produce 2D layers. These layers are further stabilized by intermolecular hydrogen bonds to construct a 3D framework showing high thermal stability (445 °C). 相似文献
993.
Volodymyr Babizhetskyy Dr. Kurt Hiebl Hansjürgen Mattausch Arndt Simon 《无机化学与普通化学杂志》2010,636(7):1229-1235
New ternary rare earth metal boride carbides with compositions close to RE10B9C10 (RE = Gd, Tb) were prepared from the elements by melting around 1800 K followed by annealing in silica tubes at 1270 K for one month. The crystal structure of the terbium compound was solved by single‐crystal X‐ray diffraction. It crystallizes in a new structure type in the monoclinic space group P21/c, a = 7.937(1), b = 23.786(2), c = 11.172(1) Å, β = 133.74(1)°, Z = 4, R1 = 0.045 (wR2 = 0.11) for 5713 reflections with Io > 2σ(Io). In the structure BC2 units and single carbon atoms are attached to a zigzag boron chain forming the unprecedented B18C18 branching unit with a B–B distance of 2.42(2) Å between these units. In addition isolated carbon atoms occupy the centres of elongated octahedra formed by rare earth metal atoms. Disorder in the terbium position together with anomalous displacement ellipsoids for carbon atoms except of those in the BC2 fragments can be rationalized in terms of a slight deviation in stoichiometry, Tb10B9+xC10–x (x ≈? 0.2). The terbium compound is ferromagnetic below TC ≈? 45 K. Due to the presence of moderately narrow domain walls the magneto‐crystalline energy is small. 相似文献
994.
Christine Walbaum Ingo Pantenburg Peter Junk Glen B. Deacon Gerd Meyer Prof. Dr. 《无机化学与普通化学杂志》2010,636(8):1444-1446
Black single crystals of [Lu(Db18c6)(H2O)3(thf)6]4(I3)2(I5)6(I8)(I12) were obtained from lutetium, I2 and Db18c6 (dibenzo‐18‐crown‐6) in THF solution. In the bulky cation, Lu3+ is surrounded by nine oxygen atoms, six of Db18c6 and three of water molecules to which two THF molecules are attached each. Meanwhile, four polyiodide anions, (I3)–, (I5)–, (I8)2– and (I12)2–, in a 2:6:1:1 ratio form a three‐dimensional network and leave space for the bulky cations. 相似文献
995.
Friedrich Schoder Ulrike Plaia Robert Metzner Wilfried Sperber Wolfgang Beck Wolf Peter Fehlhammer Prof. Dr. 《无机化学与普通化学杂志》2010,636(5):700-709
The reactions of [Re(CO)6]+, [FeCp(CO)2CS]+ and [FeCp(CNPh)3]+ with the metallo nitrile ylides [M–{C+=N–C–(H)CO2Et}(CO)5]– (M = Cr, W) and the chromio nitrile imine [Cr–{C+=N–N–H}(CO)5]– (generated by mono‐α‐deprotonation of the parent isocyanide complexes) to give neutral 5‐metallated 1,3‐oxazolin‐ ( 1 ), 1,3‐thiazolin‐ ( 2 ), imidazolin‐ ( 3 , 4 ), 1,3,4‐oxdiazolin‐ ( 5 ), 1,3,4‐thiadiazolin‐ ( 6 ) and 1,3,4‐triazolin‐2‐ylidene ( 8 ) chromium and tungsten complexes represent the first all‐organometallic versions of Huisgen’s 1,3‐dipolar cycloadditions. The formation of 6 and 8 is accompanied by partial decomposition to (OC)5Cr–C≡N–FeCpL2 {L = CO ( 7 ), CNPh ( 9 )}. The structures of 4a and 5 have been characterized by X‐ray diffraction. 相似文献
996.
Michael Veith Prof. Dr. Dr. h.c. Andreas Rammo Oliver Schütt Volker Huch 《无机化学与普通化学杂志》2010,636(7):1212-1221
The branched tripodal chloro‐methyl‐siloxanes of the general formula tBuSi[{OSiMe2}yOSiMe3–xClx]3 [x = 0–3; y = 0–2] were synthesized, starting with tert‐Butyl‐trisilanol ( 1 ). The treatment of 1 with the chloro‐methyl‐silanes (Me3–xSiClx+1) (x = 0–3) in the presence of triethylamine leads to the compounds tBuSi(OSiMe2Cl)3 ( 2 ), tBuSi(OSiMeCl2)3 ( 3 ) and tBuSi(OSiCl3)3 ( 4 ). The siloxanes 2 – 4 are colourless oily liquids, which can be purified by distillation. Their yields decrease with the number of chloro substituents. In the reaction of compound 2 with three equivalents of water the silantriol tBuSi(OSiMe2OH)3 ( 5 ) is generated which is used to create the branched tripodal chloro‐methyl‐siloxanes tBuSi(OSiMe2OSiMe3)3 ( 6 ), tBuSi(OSiMe2OSiMe2Cl)3 ( 7 ), tBuSi(OSiMe2OSiMeCl2)3 ( 9 ) and tBuSi(OSiMe2OSiCl3)3 ( 10 ). Compound ( 7 ) is only a side product with a yield of 25 %., The cyclic tBuSi[{(OSiMe2)2Cl}(OSiMe2)3O] ( 8 ) can be isolated and characterised. The transformation of the compound tBuSi(OSiMe2OSiMe2Cl)3 ( 7 ) into the trisilanol tBuSi(OSiMe2OSiMe2OH)3 ( 11 ) allows to prepare the tripodale siloxane tBuSi(OSiMe2OSiMe2OSiMe3)3 ( 12 ) in good yields., The reaction of tBuSi(OSiMe2Cl)3 ( 2 ) with tert‐butyl trisilanol 1 leads to the formation of bicyclic tBuSi(OSiMe2O)3SitBu ( 13 ). An X‐ray structure determination on 13 reveals a [3.3.3]‐bicycle with a C3 axis, which crystallizes in the cubic crystal system in the space group Pa . The reported compounds 2 – 13 were characterised by NMR‐ and IR spectroscopy ( 5 , 11 ) and show correct elemental analyses. The 29Si‐NMR‐data of the compounds show interesting trends with respect to the Si–O chain length and the chloro substistuents. 相似文献
997.
Bis(tetraphenylphosphonium) hexachloridodiberyllate, (Ph4P)2[Be2Cl6], reacts with excess trimethylsilyl‐iso‐thiocyanate to give a mixture of colourless single crystals of (Ph4P)2[Be(NCS)4] ( 1 ) and (Ph4P)4[{Be2(NCS)4(μ‐NCS)2}{Be2(NCS)6(μ‐H2N2C2S2)}] ( 2 ), which can be separated by selection. Both complexes were characterized by X‐ray diffraction. Compound 1 can be prepared without by‐products by treatment of (Ph4P)2[BeCl4] with excess Me3SiNCS in dichloromethane solution. 1 : Space group I41/a, Z = 4, lattice dimensions at 100(2) K: a = b = 1091.2(1), c = 3937.1(3) pm, R1 = 0.0474. The [Be(NCS)4]2– ion of 1 forms tetragonally distorted tetrahedral anions with Be–N distances of 168.4(2) pm and weak intermolecular S ··· S contacts along [100] and [010]. 2 ·4CH2Cl2: Space group P , Z = 1, lattice dimensions at 100(2) K: a = 919.5(1), b = 1248.3(1), c = 2707.0(2) pm, α = 101.61(1) °, β = 95.08(1) °, γ = 94.52(1) °, R1 = 0.103. Compound 2 contains two different anionic complexes in the ratio 1:1. In {Be2(NCS)4(μ‐NCS)2}2–, the beryllium atoms are connected by (NCS)– bridging groups forming centrosymmetric eight‐membered Be2(NCS)2 rings with distances Be–N of 168(1) pm and Be–S of 235.2(9) pm. The second anion {Be2(NCS)6(μ‐H2N2C2S2)}2– consists of two {Be(NCS)3}– units, which are linked by the nitrogen atoms of the unique dimeric cyclo‐addition product of HNCS with Be–N distances of 179(1) pm. 相似文献
998.
Wojciech Marynowski Tomasz Klucznik Katarzyna Baranowska Anna Dołęga Dr. Wiesław Wojnowski 《无机化学与普通化学杂志》2010,636(5):685-687
Tri(mesityloxy)silanethiol (TMST) was isolated as the only product of the reaction between SiS2 and 2,4,6‐trimethylphenol. TMST crystallizes in the triclinic system. Good quality of the crystal allowed the unrestricted refinement of the mercapto group; the resulting S–H distance is 1.29(4) Å and the Si–S–H bond angle is 95.4(17)°. Molecules of TMST show no hydrogen bonds in the crystal – the FT‐IR spectrum of the solid sample exhibits a very sharp, well‐resolved band of isolated –SH group at 2562 cm–1. 相似文献
999.
Hans J. Breunig Prof. Dr. Enno Lork Ovidiu Moldovan Ciprian I. Raţ 《无机化学与普通化学杂志》2010,636(6):1090-1094
The iron complexes [(Et2Sb)4Fe4(CO)14] ( 1 ), [(nPr2Sb)4Fe3(CO)10] ( 2 ), [{(Me3SiCH2)2Sb}4Fe2(CO)6] ( 3 ), and [2‐(Me2NCH2)C6H4SbFe2(CO)8] ( 4 ) were prepared by reactions of distibanes with Fe2(CO)9. Compounds 1 – 4 were characterized by X‐ray diffraction, 1H NMR and IR spectroscopy as well as mass spectrometry; complex 1 was additionally characterized by density functional calculations. 相似文献
1000.
M. Sakairi T. Kikuchi T. Suda D. Nagasawa M. Sato 《Surface and interface analysis : SIA》2010,42(4):215-220
X‐ray diffraction measurements were performed using synchrotron radiation at the SPring‐8 facility and electrochemical techniques to investigate the effect of polishing methods and storage conditions on the crystal structure of air‐formed oxide films and anodic oxide films formed on highly pure aluminum. Storage in an N2 environment hinders local film breakdown during anodizing, and it was established that the X‐ray diffraction measurements showed the presence of a γ‐Al2O3 in the anodic oxide film formed on mechanically polished (MP) specimens. Formation of γ‐Al2O3 during anodizing was inhibited by electropolishing because of the removal of the work‐hardened layer that was formed on the MP by electro‐polishing. The X‐ray diffraction results do not show clear differences in the influence of the polishing method on the crystal structure of air formed oxide film. This is due to the very fast oxidation rate of the air‐formed oxide film and very long storage times for the X‐ray measurements. The anodic oxide film formed on aluminum, which has a very flat surface, shows color and the color depended on grain orientation. The electrochemical impedance of the MP specimen is slightly lower than that of the mechanically and then electrochemically polished specimen at the middle frequency range. This impedance difference may be due to formation of γ‐Al2O3 in the amorphous anodic oxide film and the thickness of the film. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献