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621.
Mátyás Czugler Edwin Weber 《Journal of inclusion phenomena and macrocyclic chemistry》1991,10(3):355-366
1,1'-Binaphthyl-2,2'-dicarboxylic acid (1) forms crystalline inclusion compounds with 1-PrOH (2:1) andt-BuOH (1:1). X-ray crystal structures of the two inclusion compounds are reported. Crystals of1·1-PrOH (2: 1) show triclinic (
) symmetry with the unit cell dimensionsa = 10.160(1),b = 14.050(2),c = 15.167(1) Å = 100.37(1), = 104.40(1), and =94.82(1)°. Crystals of1s·t-BuOH (1: 1) are monoclinic (P21/n) with the cell dimensionsa = 10.603(5),b = 14.377(4),c = 15.664(7) Å, = 104.24(4)°. In both structures, H-bonded loops involving host –000H functions and guest –OH groups establish the supramolecular association. They relate these coordinatoclathrates to previous alcohol inclusions of1. Due to the unusual 2:1 (host: guest) stoichiometry, additional dimer-like interactions between –000H groups of host molecules are found in the 1-PrOH inclusion compound. From the point of view of topology these structures can be referred to as channel inclusion compounds. 相似文献
622.
Toschitake Iwamoto 《Journal of inclusion phenomena and macrocyclic chemistry》1996,24(1-2):61-132
One-, two- and three-dimensional CN-bridged metal complex structures made up of building blocks such as linear [Ag(CN)2]–, square planar [Ni(CN)4]2– or tetrahedral [Cd(CN)4]2–, and of the complementary ligands such as ammonia, water, unidentate amine, bidentate a,w- diaminoalkane, etc., are reviewed with an emphasis on their behaviour as hosts to afford clathrate inclusion compounds with guest molecules and as self-assemblies to form supramolecular structures with or without guests. The historical background is explained for Prussian blue and Hofmann's benzene clathrate based on their single crystal structure determinations. The strategies the author and coworkers have been applying to develop varieties of clathrate inclusion compounds from the Hofmann-type are demonstrated with the features observed for the developed structures determined by single crystal X-ray diffraction methods.Abbreviations for Ligands and Guests mma
NMeH2
- dma
NMe2H
- tma
NMe3
- mea
NH2(CH2)2OH
- en
NH2(CH2)2NH2
- pn
NH2CHMeCH2NH2
- tn
NH2(CH2)3NH2
- dabtn
NH2(CH2)4NH2
- daptn
NH2(CH2)5NH2
- dahxn
NH2(CH2)6NH2
- dahpn
NH2(CH2)7NH2
- daotn
NH2(CH2)8NH2
- danon
NH2(CH2)9NH2
- dadcn
NH2(CH2)10NH2
- mtn
NMeH(CH2)3NH2
- dmtn
NMe2(CH2)3NH2
- detn
NEt2(CH2)3NH2
- temtn
NMe2(CH2)3NMe2
- dien
NH2(CH2)2NH(CH2)2NH2
- pXdam
p-C6H4(NH2CH2)2
- rnXdam
m-C6H4(NH2CH2)2
- py
C5H5N pyridine
- ampy
NH2C5H4N aminopyridine
- Clpy
CIC5H4N chloropyridine
- Mepy
MeC5H4N methylpyridine
- dmpy
Me2C5H3N dimethylpyridine
- bpy
NC5H4C5H4N bipyridine
- quin
C7H9N quinoline
- iquin
iso-C7H9N isoquinoline
- qxln
C8H6N2 quinoxaline
- Pe
C5H11-pentyl imH: C3N2H4 imidazole
- pyrz
N(CHCH)2N pyrazine
- Mequin
MeC7H8N methylquinoline
- bppn
C13H14N2 1,3-bis(4-pyridyl)propane
- bpb
C14H8N2 1,4-bis(4-pyridyl)butadiyne
- N-Meim
C3N2H3Me N-methylimidazole
- 2-MeimH
C3N2H3Me 2-methylimidazole
- dmf
HOCNMe2 dimethylformamide
- hmta
C6H12N4 hexamethylenetetramine
-
o-phen
C12H8N2 1,10-phenanthroline
- den
HN(CH2CH2)2NH piperazine
- morph
HN(CH2CH2)2O morpholine
- ten
N(CH2CH2)3N 1,4-diazabicyclo[2.2.2]octane
- ameden
NH2(CH2)2N(CH2CH2)2NH N-(2-aminoethyl)piperazine
Presented at the Sixth International Seminar on Inclusion Compounds, Istanbul, Turkey, 27–31 August, 1995. 相似文献
623.
合成了一种新的硫尿-阳离子主体晶格包合物[(C_2H_5)_4N~+]_2C_4H_4O_6~ (2-)·2(NH_2)_2CS·2H_2O,并通过单晶X射线衍射法对其进行了晶体结构测定。 结果表明该晶体属单斜晶系,P2_1空间群,晶胞参数a = 0.7727(2) nm,b = 1. 4707(4) nm,c = 1.4645(4) nm,β = 95.161(5)°,Z = 2,R_1 = 0.0488。晶 体为“三明治”式夹层结构,波形平面主体氢键网状结构由[酒石酸根-硫尿_2]三 聚体形成的双纽带,在两个水分子的桥连氢键连接下形成的。酒石酸根在主体晶格 的氢键形成中起到重要作用。 相似文献
624.
Czugler M Weber E Párkányi L Korkas PP Bombicz P 《Chemistry (Weinheim an der Bergstrasse, Germany)》2003,9(16):3741-3747
Facile chemical synthesis of the natural chiral-pool-derived host 1 and its subsequent crystallization ("supramolecular synthesis") from different solvents yielded crystalline assemblies. Crystal structure determinations of five of the so formed solvent-inclusion compounds (1 a-1 e) reveal hexagonal symmetries in four cases. The structural characteristics of these chiral host-guest ensembles with varying stoichiometries can be best described as assemblies formed through intra-pair hydrogen bridges of host molecules into Piedfort pairs of differing complexity. Hitherto undescribed, these Piedfort pairs also form even larger regular assemblies that we designate "Big Mac"-like shapes. In the only nonhexagonal case, six independent host molecules form a huge supramolecular analogue of [6]benzocyclophane, also known as [6]chochin, extending this giant supermolecule through intermolecular hydrogen bonds into macroscopic (mm-size) dimensions. As all these crystals are inherently chiral, and new model systems for solid-state applications can be envisaged. 相似文献
625.
报道了应用于溶液法制备器件的小分子蓝光主体材料2-叔丁基-9,10-二(9,9-二正丙基芴基)蒽(TBPFA), 合成路线如Scheme 1所示, 该化合物具有较高的荧光量子效率,以它作为主体材料, 采用旋涂法制备了掺杂与非掺杂型单层器件, 并对器件性能进行了初步研究. 相似文献
626.
Internet防火墙及其应用 总被引:1,自引:0,他引:1
初步地探讨了防火墙的概念,作用及实现防火墙采用的不同技术和防火墙的几种基本结构,最后讨论了防火墙在新疆大学校园网中应用。 相似文献
627.
Harry W. Gibson Aurica Farcas Jason W. Jones Zhongxin Ge Feihe Huang Matthew Vergne David M. Hercules 《Journal of polymer science. Part A, Polymer chemistry》2009,47(14):3518-3543
Dibenzo‐24‐crown‐8‐terminated polystyrene ( 5 ) was chain extended to “dimeric” 8 by pseudorotaxane formation with a ditopic guest, α,ω‐bis[p‐(N‐benzylammoniomethyl)phenoxy]heptane bis(hexafluorophosphate) ( 7 ). The three‐armed star polymer 11 was similarly formed by complexation of the dibenzo‐24‐crown‐8‐terminated polystyrene ( 5 ) with a tritopic secondary ammonium salt, 1,3,5‐tris[p‐(benzylammoniomethyl)phenyl]benzene tris(hexafluorophosphate) ( 10 ). Another three‐armed star polymer 13 was self‐assembled from dibenzo‐24‐crown‐8‐terminated polystyrene ( 5 ) and a tetratopic paraquat compound, 1,2,4,5‐tetrakis{p‐N‐[(N′‐methyl‐4,4′‐bipyridinium)methylphenyl]}benzene octakis(hexafluorophosphate) ( 12 ). The above chain extension and star polymer formation processes seemed to be cooperative; that is, the second and third complexation steps proceed with stepwise higher efficiencies than statistically expected. Dibenzo‐24‐crown‐8‐terminated polystyrene ( 5 ) was chain extended with secondary ammonium terminated polystyrene 14 , forming 16 , and also self‐assembled with a secondary ammonium ion terminated polyisoprene 15 to form supramolecular block copolymer 17 . These processes were examined by NMR, mass spectrometry and viscometery. Thus, although binding in these systems is not particularly strong (association constants <104 M?1), these examples provide proof‐of‐principle that pseudorotaxane formation is a viable concept for chain extension and self‐assembly of novel types of block copolymers and star polymers. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 3518–3543, 2009 相似文献
628.
Poly(ethylene imine)‐graft‐poly(ethylene oxide) (PEI‐g‐PEO) copolymers were synthesized via Michael addition reaction between acryl‐terminated poly(ethylene oxide) methyl ether (PEO) and poly(ethylene imine) (PEI). The brush‐like copolymers were characterized by means of Fourier transform infrared spectroscopy and nuclear magnetic resonance spectroscopy. It is found that the crystallinity of the PEO side chains in the copolymers remained unaffected by the PEI backbone whereas the crystal structure of PEO side chains was altered to some extent by the PEI backbone. The crystallization behavior of PEO blocks in the copolymers suggests that the bush‐shaped copolymers are microphase‐separated in the molten state. The PEO side chains of the copolymers were selectively complexed with α‐cyclodextrin (α‐CD) to afford hydrophobic side chains (i.e., PEO/α‐CD inclusion complexes). The X‐ray diffraction (XRD) shows that the inclusion complexes (ICs) of the PEO side chains displayed a channel‐type crystalline structure. It is identified that the stoichiometry of the inclusion complexation of the PEI‐g‐PEO with α‐CD is close to that of the control PEO with α‐CD. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 2296–2306, 2008 相似文献
629.
本文对Judd-Ofelt光谱分析理论(J-O理论)的发展和应用进行了综述.J—O理论用于分析固体中的稀土离子的吸收、发射光谱,可计算它们的跃迁几率、谱线强度、能级寿命、发射截面等. 相似文献
630.
Organic–inorganic hybrid brushes comprised of macrocyclic oligomeric silsesquioxane (MOSS) and poly(ε‐caprolactone) (PCL) were synthesized via the ring‐opening polymerization of ε‐caprolactone (CL) with cis‐hexa[(phenyl) (2‐hydroxyethylthioethyldimethylsiloxy)]cyclohexasiloxane as the initiator. The MOSS macromer bearing hydroxyl groups was synthesized via the thiol‐ene radical addition reaction between cis‐hexa[(phenyl)(vinyldimethylsiloxy)]cyclohexasiloxane and β‐mercaptoethanol. The organic–inorganic PCL cyclic brushes were characterized by means of nuclear magnetic resonance spectroscopy (NMR) and gel permeation chromatography (GPC). These MOSS–PCL brushes were then used to prepare the supramolecular inclusion complexes with α‐cyclodextrin (α‐CD). The X‐ray diffraction (XRD) indicates that the organic–inorganic inclusion complexes (ICs) have a channel‐type crystalline structure. It is noted that the molar ratios of CL unit to α‐CD for the organic–inorganic ICs are quite dependent on the lengths of the PCL chains bonded to the silsesquioxane macrocycle. While the PCL chains were short, the efficiency of inclusion complexation was significantly decreased. The decreased efficiency could be attributed to the repulsion of the adjacent PCL chains bonded to the silsesquioxane macrocycle and the restriction of the bulky silsesquioxane macrocycle on the motion of PCL chains; this effect is pronounced with decreasing the length of the PCL chains. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2009 相似文献