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981.
H. H. Willard J. J. Thompson E. Kasper P. Slawik A. W. Middleton K. Seelkopf H. Taeger P. Schmidt F. Weyrauch A. Necke H. Müller A. J. Lindsey B. Park E. J. Lewis O. B. Winter Helen M. Robinson F. W. Lamb E. J. Miller C. E. Willoughby E. S. Wilkins E. O. Kraemer A. Jílek und J. Kota 《Fresenius' Journal of Analytical Chemistry》1936,106(4-6):200-207
Ohne Zusammenfassung 相似文献
982.
983.
Dr. Yuzhong Wang Dr. Yaoming Xie Dr. Pingrong Wei Soshawn A. Blair Dr. Dongtao Cui Prof. Dr. Michael K. Johnson Prof. Dr. Henry F. Schaefer III Prof. Dr. Gregory H. Robinson 《Angewandte Chemie (International ed. in English)》2018,57(26):7865-7868
Whereas low‐temperature (?78 °C) reaction of the lithium dithiolene radical 1 . with boron bromide gives the dibromoboron dithiolene radical 2 ., the parallel reaction of 1 . with (C6H11)2BCl (0 °C) affords the dicyclohexylboron dithiolene radical 3 .. Radicals 2 . and 3 . were characterized by single‐crystal X‐ray diffraction, UV/Vis, and EPR spectroscopy. The nature of these radicals was also probed computationally. Under mild conditions, 3 . undergoes unexpected thiourea‐mediated B?C bond activation to give zwitterion 4 , which may be regarded as an anionic dithiolene‐modified carbene complex of the sulfenyl cation RS+ (R=cyclohexyl). 相似文献
984.
Synthesis and Biological Evaluation of the Antimicrobial Natural Product Lipoxazolidinone A
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Jonathan J. Mills Kaylib R. Robinson Troy E. Zehnder Prof. Joshua G. Pierce 《Angewandte Chemie (International ed. in English)》2018,57(28):8682-8686
Natural products have historically been a major source of antibiotics and therefore novel scaffolds are constantly of interest. The lipoxazolidinone family of marine natural products, with an unusual 4‐oxazolidinone heterocycle at their core, represents a new scaffold for antimicrobial discovery; however, questions regarding their mechanism of action and high lipophilicity have likely slowed follow‐up studies. Herein, we report the first synthesis of lipoxazolidinone A, 15 structural analogues to explore its active pharmacophore, and initial resistance and mechanism of action studies. These results suggest that 4‐oxazolidinones are valuable scaffolds for antimicrobial development and reveal simplified lead compounds for further optimization. 相似文献
985.
986.
987.
988.
Samuel A. Sangokoya William T. Pennington Gregory H. Robinson 《Journal of chemical crystallography》1990,20(1):53-57
The crystalline product {[Se(CH3)3][(CH3)AlCl3]}n was prepared from reaction of SeCl4 with A1(CH3)3 in heptane. The organo-main group polymer crystallizes in the monoclinic space group P21/c with unit cell parametersa=11.218(3) Å,b=11.119(3) Å,c=9.915(2) Å,=107.82(2)°,V=1177.4(5) Å3, andD
calcd=1.54 g cm–3 forZ=4. Least-squares refinement based on 1195 observed reflections I>3(I) in the range 3.50°<2<45.0° led to a finalR factor of 0.036 (R
w=0.047). The asymmetric unit contains one selenonium ion, Se(CH3)
3
+
, and one organoaluminum anionic species, (CH3)AlCl
3
–
. Secondary interactions (SeCl) serve to link the ions along two dimensions to form infinite layers. Thus, {[Se(CH3)3] [(CH3)A1C13]}n may be regarded as a layered organoaluminum-selenium polymer. The mean Se-C bond distance is 1.921(5) Å while the mean C-Se-C bond angle is 99.1(4)°. The independent Al-C bond distance is 1.927(8) Å while the mean Al-Cl bond distance is 2.166(7) Å. 相似文献
989.
Jerry L. Atwood Peter C. Junk Michael T. May Kerry D. Robinson 《Journal of chemical crystallography》1994,24(4):243-245
[H3O+·18-crown-6][Br–Br–Br–] crystallizes in the triclinic space group P 1 witha=6.105(1),b=8.658(1),c=11.072(1)Å, =71.35(1), =77.58(1), =71.09(1)0, andD
c=1.68 g cm–3 forZ=1. Refinement based on 1112 observed reflections led toR=0.044. The cation exhibits a planar oxonium ion bonded symmetrically to the 18-crown-6 (O(oxonium) resides 0.092 Å out of the plane of the crown ether oxygen atoms). The anion also resides on a center of inversion with Br–Br=2.530(1)Å. 相似文献
990.
Jameica B. Hill Terrence A. Talley William T. Pennington Gregory H. Robinson 《Journal of chemical crystallography》1994,24(1):61-65
The crystalline products [Me2Al–N(CH2CH2)2–C–(OCH2)2]2 (I) and [Me2Ga–N(Si(H)Me2)2]2 (II) were prepared from reactions of trimethylaluminum and trimethylgallium with 1,4-dioxa-8-azaspiro[4.5]-decane and 1,1,3,3-tetramethyldisilazane, respectively, in toluene. The organoaluminum dimer crystallizes in the monoclinic space groupP21/c with unit cell parametersa=8.970(2) ,b=9.683(2) ,c=12.833(3) , =103.18(2)°,V=1085.3(3) 3, andD
calcd=1.22 g cm–3 forZ=2. Least-squares refinement based on 935 observed reflectionsI>3(I) in the range 3.5°<2<45.0° led to a finalR factor of 0.033 (R
w
=0.041). The dimeric organosilazagallium crystallizes in the triclinic space group
with unit cell parametersa=7.636(2) ,b=9.168(2) ,c=9.466(3), =72.81(2)°, =87.94(2)°, =69.90(2)°,V=593.0(3) 3, andD
calcd=1.30 g cm–3 forZ=1. Least-squares refinement based on 1661 observed reflectionsI>3(I) in the range 3.5°<2<48.0° led to a finalR factor of 0.055 (R
w
=0.070). Both compoundsI andII reside about a crystallographic center of symmetry and contain a planar M2N2 (M=Al forI, Ga forII) four-membered ring withI having an Al...Al contact of 2.801 . 相似文献