“…The reaction of dimethyl­amine hydro­chloride, 18-crown-6 and ferric chloride in ethanol yields the title compound, (C(2)H(8)N)[FeCl(4)]·C(12)H(24)O(6), which exhibits an unusual supramolecular structure. …”
Enlace del recurso
Enlace del recurso
Enlace del recurso

“…The six O atoms of the crown ether lie approximately in a plane [mean deviation 0.2129 (3) Å]; the N atom is displaced by 0.864 (3)Å from the centroid of the 18-crown-6 ring. …”
Enlace del recurso
Enlace del recurso
Enlace del recurso

“…The six O atoms of the crown ether lie approximately in a plane, the mean deviation being 0.1771 (3) Å; the N atom lies approximately 0.855 (3) Å from the centroid of the crown ether ring.…”
Enlace del recurso
Enlace del recurso
Enlace del recurso

Enlace del recurso
Enlace del recurso
Enlace del recurso

“…In the crystal structure of the title organic salt, C(3)H(10)NO(+)·IO(4) (−)·C(12)H(24)O(6), the protonated 2-meth­oxy­ethanaminium (CH(3)OC(2)H(4)—NH(3) (+)) cation forms a 1:1 supra­molecular rotator–stator complex with the 18-crown-6 mol­ecule via N—H⋯O hydrogen bonds. The (CH(3)OC(2)H(4)—NH(3) (+)) group is attached from the convex side of the bowl-shaped crown, in contrast to similar ammonium cations that nest in the curvature of the bowl. …”
Enlace del recurso
Enlace del recurso
Enlace del recurso

Enlace del recurso
Enlace del recurso
Enlace del recurso

Enlace del recurso
Enlace del recurso
Enlace del recurso

“…In the title compound, C(6)H(7)ClN(+)·ClO(4) (−)·C(12)H(24)O(6), the cation forms a 1:1 complex with the crown ether, viz [C(6)H(7)ClN-(18-crown-6)](+), in which the –NH(3) (+) unit nests in the crown and inter­acts with it through bifurcated N—H⋯O hydrogen bonding. …”
Enlace del recurso
Enlace del recurso
Enlace del recurso

“…The title compound, C(2)H(2)·C(12)H(24)O(6)·2NH(3), was formed by co-crystallization of 18-crown-6 and acetyl­ene in liquid ammonia. The 18-crown-6 mol­ecule has threefold rotoinversion symmetry. …”
Enlace del recurso
Enlace del recurso
Enlace del recurso

“…BACKGROUND: Crowned dens syndrome (CDS), related to microcrystalline deposition in the periodontoid process, is the main cause of acute or chronic cervical pain. …”
Enlace del recurso
Enlace del recurso
Enlace del recurso

“…Surgical crown lengthening procedure is done to increase the clinical crown length without violating the biologic width. …”
Enlace del recurso
Enlace del recurso
Enlace del recurso

“…We report the case of a patient who experienced barotrauma involving dislodgement of a provisional crown during scuba diving. Patients who are exposed to pressure changes as a part of their jobs or hobbies and their dentists should know the causes of barotrauma. …”
Enlace del recurso
Enlace del recurso
Enlace del recurso

“…The co-crystal, C(7)H(9)N(4)O(2) (+)·ClO(4) (−)·C(20)H(24)O(6)·3.25H(2)O, consists of theobrominium (3,7-di­methyl-2,6-dioxo-1H-purin-9-ium) cations, perchlorate anions and dibenzo-18-crown-6 and water mol­ecules. The crown ether is in a bent conformation, in which the planes of the aromatic rings subtend an angle of 63.7 (1)°. …”
Enlace del recurso
Enlace del recurso
Enlace del recurso

“…The study aims to compare the wear behavior of conical crowns using electroplated copings (group E) with standard telescopic crowns with cast female parts (group C). …”
Enlace del recurso
Enlace del recurso
Enlace del recurso

“…OBJECTIVES: The aim of this study was to investigate the internal fit (IF) of glass-infiltrated alumina (ICA - In-Ceram Alumina), yttria-stabilized tetragonal zirconia polycrystals (Y-TZP - IPS e.max ZirCAD), and metal-ceramic (MC - Ni-Cr alloy) crowns. MATERIAL AND METHODS: Sixty standardized resin-tooth replicas of a maxillary first molar were produced for crown placement and divided into 3 groups (n=20 each) according to the core material used (metal, ICA or Y-TZP). …”
Enlace del recurso
Enlace del recurso
Enlace del recurso

“…Here, the tooth, core, and post complex, on which the crown is cemented, may fracture off from the abutment, causing the crown to separate from the abutment, while the cement that bonds the crown to the tooth, core, and post complex remains intact, such that the tooth, core, and post complex remains inside the crown when the crown separates from the abutment. …”
Enlace del recurso
Enlace del recurso
Enlace del recurso

“…However, integration of all new observations into the most complete phylogenetic analysis that support the pleurodiran nature of P. robusta reveals that this taxon is more parsimoniously placed along the phylogenetic stem of crown Testudines. All current phylogenetic hypotheses therefore support the basal placement of this taxon, imply that the sutured pelvis of this taxon developed independently from that of pleurodires, and conclude that the age of the turtle crown is Middle Jurassic.…”
Enlace del recurso
Enlace del recurso
Enlace del recurso

“…Crown fractures account for the majority of dental traumas. …”
Enlace del recurso
Enlace del recurso

“…Considering this spatially continuous variable allows to describe the spatiotemporal evolution of the tree crown by means of 3D partial differential equations. …”
Enlace del recurso
Enlace del recurso
Enlace del recurso

“…Red crystals of the title salt, [K(C(12)H(24)O(6))][Sb(C(6)H(5))(2)], were obtained by the reaction of SbPh(3), KSnBi and 18-crown-6 in liquid ammonia. The asymmetric unit contains one half of a [K(18-crown-6)](+) cation and one half of an SbPh(2) (−) anion, with the central element lying on a twofold axis and a centre of inversion, respectively. …”
Enlace del recurso
Enlace del recurso
Enlace del recurso