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51.
52.
In the title compound, [UO2(C15H11O2)2(C14H14OS)], the UVI atom is coordinated by seven O atoms in a distorted pentagonal–bipyramidal geometry. Both di­phenyl­propane‐1,3‐dionate systems are nearly planar. The sulfoxide moiety is in a distorted tetrahedral geometry, while its two aromatic rings are nearly orthogonal to one another. The crystal packing is stabilized by two bifurcated hydrogen‐bonding interactions involving both uranyl O atoms.  相似文献   
53.
Copper(II) complex with piperidine-4-carboxylic acid (HPipe-4), Cu(HPipe-4)4(ClO4)2 (I) was prepared and characterized by IR, X-ray diffraction, and thermal analysis. The crystal is orthorhombic with space group Ccca, Z = 8, a =17.415(3) , b =17.399(2) , c = 21.426(3) . The copper atom has a square surrounding and is coordinated by four carboxylato oxygen atoms in monodentate coordination mode. Full-matrix least-squares refinements gave a final R value of 0.0723 for 22169 reflections. The complex consists of two perpendicularly arranged molecules differing slightly in conformations and shows a three-dimensional polymeric structure formed by hydrogen bonds.__________From Koordinatsionnaya Khimiya, Vol. 31, No. 4, 2005, pp. 302–305.Original English Text Copyright © 2005 by Yang, Zhang, Tian, Wu, Liu, Usman, Chantrapromma, Fun.This article was submitted by the authors in English.  相似文献   
54.
In the title complex, C6H12N4·C8H8O3, the hexa­methyl­ene­tetramine mol­ecule accepts a single intermolecular O—H?N hydrogen bond from the hydroxy group of the 4‐hydroxy‐3‐methoxy­benz­aldehyde moiety. The non‐centrosymmetric crystal structure is built from alternating molecular sheets of 4‐hydroxy‐3‐methoxy­benz­aldehyde and hexa­methyl­ene­tetramine mol­ecules, and is stabilized by intermolecular O—H?N, C—H?O and C—H?π interactions.  相似文献   
55.
In the title compound, C20H16N2O5, both of the 1‐acetyl­isatin (1‐acetyl‐1H‐indole‐2,3‐dione) moieties are planar and form a dihedral angle of 74.1 (1)°. Weak intermolecular hydrogen bonds and C—H?π interactions stabilize the packing in the crystal.  相似文献   
56.
In the title 1/2/2 adduct, C4H12N22+·2C6H3N2O5?·2H2O, the dication lies on a crystallographic inversion centre and the asymmetric unit also has one anion and one water mol­ecule in general positions. The 2,4‐di­nitro­phenolate anions and the water mol­ecules are linked by two O—H?O and two C—H?O hydrogen bonds to form molecular ribbons, which extend along the b direction. The piperazine dication acts as a donor for bifurcated N—H?O hydrogen bonds with the phenolate O atom and with the O atom of the o‐nitro group. Six symmetry‐related molecular ribbons are linked to a piperazine dication by N—H?O and C—H?O hydrogen bonds.  相似文献   
57.
Cochinchinones I-L (1-3 and 13) along with 11 known xanthones (4-12, 14, and 15) were isolated from the resin and green fruits of Cratoxylum cochinchinense. In addition, four new acetylated compounds (16-19) were derivatized from 7-geranyloxy-1,3-dihydroxyxanthone (14) and 3-geranyloxy-1,7-dihydroxyxanthone (15). All compounds were characterized on the basis of spectroscopic analyses. The structures of cochinchinone I (1), a monoacetate (18) and a dibrosylate (20), were also confirmed by X-ray diffraction analysis. The antibacterial and antifungal activities of selected compounds were evaluated as well.  相似文献   
58.
The title compound, a novel 30-membered 2:2 macrocyclic thio­carbohydrazone, C34H32N8O4S2·3C5H5N, has been pre­pared and crystallographically characterized. The mol­ecule of the compound is twisted. One dioxa­butane group is boat-like in shape, whereas the other is highly disordered. The crystal structure is stabilized by inter- and intramolecular hydrogen bonds.  相似文献   
59.
The triclinic cell of the title compound contains 2C12H24N+·2C6H5O2S ion pairs that are linked by four hydrogen bonds [N⃛O = 2.728 (3) and 2.758 (3) Å] across a centre of inversion.  相似文献   
60.
In the title compound, C16H19ClN2O4, the pyridine ring is nearly planar, the piperidine ring is non‐planar and the cyclo­hexane ring adopts a screw‐boat conformation. The carboxyl­ate group makes a dihedral angle of 80.9 (2)° with the least‐squares plane through the cyclo­hexane ring.  相似文献   
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