Cubane Complexes with Two (or More) Group 14−Group 16 Double Bonds: Synthesis and X-ray Structures of Sn4Se2(NtBu)4 and Ge4Se3(NtBu)4

2003 ◽  
Vol 2003 (10) ◽  
pp. 1857-1860 ◽  
Author(s):  
Tristram Chivers ◽  
Timothy J. Clark ◽  
Mark Krahn ◽  
Masood Parvez ◽  
Gabriele Schatte
Keyword(s):  
Double Bonds ◽  
Group 14 ◽  
X Ray ◽  
Group 16

Cubane Complexes with Two (or More) Group 14—Group 16 Double Bonds: Synthesis and X-Ray Structures of Sn4Se2(NtBu)4 and Ge4Se3(NtBu)4.

ChemInform ◽  
2003 ◽  
Vol 34 (30) ◽  
Author(s):  
Tristram Chivers ◽  
Timothy J. Clark ◽  
Mark Krahn ◽  
Masood Parvez ◽  
Gabriele Schatte
Keyword(s):  
Double Bonds ◽  
Group 14 ◽  
X Ray ◽  
Group 16

scholarly journals The severity of clinical changes and the importance of vitamin D in the development of hyperandrogenism syndrome during puberty.

2021 ◽  
Vol 2021 (1) ◽  
pp. 88-92
Author(s):  
A.А. Talibli ◽  
◽  
E.M. Aliyeva ◽  
F.A. Kurbanova ◽  
I.R. Mustafayeva ◽  
...  
Keyword(s):  
Vitamin D ◽  
Research Methods ◽  
Clinical Manifestations ◽  
Group 14 ◽  
X Ray ◽  
The Third ◽  
Group 12 ◽  
Group 16 ◽  
Clinical Changes

The aim of the study was to study the severity of subjective and clinical manifestations, as well as the peculiarities of changes in the level of vitamin D in girls with hyperandrogenic syndrome in the dynamics of puberty. Examined 137 girls with hypenrandrogenic syndrome (HA) in the period of puberty. Clinical, hormonal, biochemical, X-ray research methods were carried out. All surveyed girls were divided by age into 3 groups: 12-13, 14-15, 16-17 years old. The first group (12-13 years old, n = 27) comprised 19.7% of girls, the second group (14-15 years old, n = 63) 46% girls, the third group (16-17 years old, n = 47) made up 34,7% of girls. The level of vitamin D was determined on a device “Finecare”.

(thf)2Ln(Ge9{Si(SiMe3)3}3)2 (Ln = Eu, Sm): the first coordination of metalloid germanium clusters to lanthanides

2021 ◽  
Author(s):  
Andreas Schnepf ◽  
Svetlana Klementyeva ◽  
Claudio Schrenk ◽  
Marat M Khusniyarov ◽  
Minghui Zhang
Keyword(s):  
Magnetic Properties ◽  
Rare Earth ◽  
Crystallographic Analysis ◽  
Rare Earth Complexes ◽  
Group 14 ◽  
X Ray ◽  
Germanium Clusters

We report the synthesis, structure and magnetic properties of the first rare earth complexes of metalloid group 14 clusters [(thf)2Ln(Ge9Hyp3)2] (Ln = Eu, Sm, Hyp = Si(SiMe3)3). X-ray crystallographic analysis...

Systhesis, Characterization and Spectroscopic Properties of (2E,6E)-2,6-Bis(2,3,4-tri-methoxy-benzylidene)cyclohexanone

2011 ◽  
Vol 396-398 ◽  
pp. 2338-2341
Author(s):  
Xing Chuan Wei ◽  
Zhi Li Liu ◽  
Kun Zhang ◽  
Zhi Yun Du ◽  
Xi Zheng
Keyword(s):  
Crystal Structure ◽  
Acetic Acid ◽  
Hydrogen Bonds ◽  
Title Compound ◽  
Spectroscopic Properties ◽  
Spectral Studies ◽  
Double Bonds ◽  
X Ray ◽  
Π Interactions ◽  
X Ray Crystallography

In this paper, (2E,6E)-2,6-Bis(2,3,4-tri-methoxy -benzylidene)cyclohexanone (omitted as tmbcho) (1) was obtained by the reaction of acetic acid, tetrahydrofuran, cyclohexanone and 2,3,4-tri-methoxy-benzaldehyde. Three non-classic hydrogen bonds were observed in the compound. X-ray crystallography shows that the crystal structure is stabilized by intermolecular C-H•••π interactions and it contains plenty of conjugated double bonds. The title compound was characterized by UV-vis and fluorescent spectral studies.

Synthesen und Strukturen von 2,5-Bis(2-arylvinyl)-1,4-benzochinonen und deren photochemisches Verhalten im Kristall / Syntheses and Crystal Structures of 2,5-Bis(2-arylvinyl)-1,4-benzoquinones and their Photochemical Reactivity in the Crystalline State

1993 ◽  
Vol 48 (10) ◽  
pp. 1411-1418 ◽  
Author(s):  
Hermann Irngartinger ◽  
Jochen Lichtenthäler ◽  
Dieter Fenske ◽  
Gerhard Baum
Keyword(s):  
Crystal Structures ◽  
Anodic Oxidation ◽  
Crystalline State ◽  
Double Bonds ◽  
Resonance Structures ◽  
Photochemical Reactivity ◽  
X Ray ◽  
Bond Lengths ◽  
Intermolecular Distances ◽  
Hydrolysis Of

The 2,5-bis(2-arylvinyl)-1,4-benzoquinones 1a-1e are formed from hydrolysis of their corresponding ketals 5 which are generated by anodic oxidation of the corresponding 1,4-dimethoxybenzene derivatives 4. The crystal structures of the quinone compounds 1a, 1d and 1e have been determined by X-ray analyses. The bond lengths of the quinone system are influenced by polar resonance structures. An α-type packing mode is observed for the three crystal structures of compounds 1. The vinylic double bonds have short intermolecular distances (1a: 4.417(5), 1d: 3.653(2), 1e: 4.224(5) Å). Only the crystals of 1d with the shortest contacts are photoreactive

Powder X-Ray Diffraction Data for the Superconducting Phase TlCaBa2Cu2O7−δ

1992 ◽  
Vol 7 (2) ◽  
pp. 115-116 ◽  
Author(s):  
Terry L. Aselage ◽  
Michael O. Eatough
Keyword(s):  
Cuprate Superconductors ◽  
General Interest ◽  
Superconducting Transition ◽  
X Ray Diffraction ◽  
Pure Compound ◽  
Group 14 ◽  
X Ray ◽  
Superconducting Phases ◽  
The Family ◽  
Unit Cells

High temperature superconducting phases in the Tl-Ca-Ba-Cu-O system are ideally represented by the formula TlmCan−1Ba2CunO2(n+1)+m, with m either 1 or 2 and n = 1 to at least 3 (Parkin et at., 1988). Each of these phases contains one or more of the nearly planar CuO2sheets common to the cuprate superconductors. A single Ca atom separates adjacent CuO2sheets (n > 1). Single or double rock salt-like Tl-O layers are separated from the Can−1CunO2nregions by single Ba-O layers. Each of the Ca-containing members of this family crystallizes in a tetgragonal unit cell, with space group 14/mmm for the m = 2 series and P4/mmm for the m = 1 series.Despite the general interest in this family of superconductors, little has been reported about the m = 1, n = 2 member, TlCaBa2Cu2O7−δ, hereafter called 1122. This lack of work is due at least in part to the difficulty in synthesizing the pure compound (Michel et at., 1991). Additionally, technological interest has focused on members of the family with higher superconducting transition temperatures, particularly Tl2Ca2Ba2Cu3Oywith Tcup to 125 K. The critical temperature of 1122 has been reported from as low as 50 K (Hervieu et al., 1988) to as high as 103 K (Morosin et al., 1988), and at several values in between (Ganguli et al., 1988; Liang et al., 1988). Most of the samples had other superconducting phases in addition to 1122. Because of the nearly identical a axis lengths of the unit cells of the Tl-family of superconductors, syntactic intergrowths may be present in such multiphase samples.

256 DRAINAGE OF ANASTOMOTIC LEAKAGE AFTER ESOPHAGECTOMY: THROUGH THE FISTULA OR NOT, WHICH IS BETTER?

2020 ◽  
Vol 33 (Supplement_1) ◽  
Author(s):  
L Dai ◽  
X Zhao ◽  
Y Yang ◽  
H Fu ◽  
K Chen
Keyword(s):  
Anastomotic Leakage ◽  
Clinical Characteristics ◽  
Drainage Tube ◽  
Critical Importance ◽  
Stable Group ◽  
Group 14 ◽  
X Ray ◽  
Mediastinal Abscess ◽  
Residual Cavity ◽  
Grade Iii

Abstract   Thoracic abscess and/or mediastinal abscess due to anastomotic leakage after esophagectomy are very serious postoperative complications, and adequate surgical drainage is of critical importance to treatment. In this study, we compared the treatment efficacies of two drainage methods (through-the-fistula or not-through-the-fistula). Methods We retrospectively collected the esophageal cancer patients who underwent surgery from Jan 2016 to Aug 2019 who had complications of anastomotic leakage which was above grade III according to Lerut grading system. The drainage methods of thoracic/mediastinal abscess were drainage tube through-the-fistula (TF) (with the aid of X-ray or endoscope) and not-through-the-fistula (nTF) (via thorax or neck). According to the time from drainage tube placed to stable of the fistula, the patients were divided into fast stable group (<14 days) and slow stable group (≥14 days), and the differences of clinical characteristics and drainage methods were compared. Results Among the 495 cases underwent surgery, 43 (8.7%) had anastomotic leakage, 20 (4.0%) of which were grade III. 8 obtained fast stable and 12 were slow stable. As to drainage efficacy, there were 87.5% and 16.7% of the cases adopted TF drainage in fast stable group and slow stable group, respectively (P = 0.002). As to safety, there were 1 case in TF group that needed repeated drainage, whereas in nTF group, there were 2 cases died of bleeding and 2 cases needed repeated drainage (P = 0.319). Furthermore, there were 2 residual cavity cases after recovery in the nTF group. Conclusion TF drainage is safe and reliable for the thoracic/mediastinal abscess caused by anastomotic leakage after esophagectomy, which was better compared to nTF drainage, and facilitated recovery of the anastomosis.

Chrom(0)-und Molybdän(0)-Komplexe von 11-Isopropyliden-bicyclo[4.4.1]undeca-2,4,8-trienen / Chromium(0) and Molybdenum(0) Complexes of 11-Isopropylidene-bicyclo[4.4. 1]undeca-2,4,8-trienes

1986 ◽  
Vol 41 (6) ◽  
pp. 722-730 ◽  
Author(s):  
Cornelius G. Kreiter ◽  
Eduard Michels ◽  
Jürgen Kaub
Keyword(s):  
Molecular Structure ◽  
Double Bond ◽  
Nmr Spectroscopy ◽  
Transition Metals ◽  
Crystal And Molecular Structure ◽  
Double Bonds ◽  
Conjugated Diene ◽  
X Ray ◽  
Ir And Nmr Spectroscopy ◽  
Elemental Analyses

11-Isopropylidene-bicyclo[4.4.1]undeca-2,4,8-triene (IBU, 1A) and five alkyl substituted de­rivatives (1B-1F) contain a conjugated diene unit and two isolated CC-double bonds, one exocyclic and one incorporated into the bicvclus, each suited for complexation to transition metals. With [Cr(CO)3(CH3CN)3] (2) 1A-1F form [Cr(CO)3(η6-IBU)] complexes (3A−3F). in which the IBU ligands are coordinated to the chromium via the diene unit and the exocyclic CC-double bond. The corresponding [Mo(CO)3(η6-IBU)] complexes (5A−5F) are obtained from the reactions of [Mo(CO)3(diglyme)] (4) with 1A−1F. In addition, the isomeric [Mo(CO)3(η6-IBU)] complexes (6A−6D) are formed, in which the IBU ligands are bound to molybdenum via the three cyclic CC-double bonds. The complexes 3A−3F, 5A−5F and 6A−6D were studied by IR and NMR spectroscopy (1H. 13C) and characterized by C, H elemental analyses. The crystal and molecular structure of 1A was determined by X-ray structure analysis.

Subvalent Group 14 metal compounds. XIV. The X-ray crystal structures of two monomeric Group 14 metal bisamides, Ge[N(SiMe3)2]2 and Sn[Me2]2

1992 ◽  
Vol 198-200 ◽  
pp. 203-209 ◽  
Author(s):  
Richard W. Chorley ◽  
Peter B. Hitchcock ◽  
Michael F. Lappert ◽  
Wing-Por Leung ◽  
Philip P. Power ◽  
...  
Keyword(s):  
Crystal Structures ◽  
Group 14 ◽  
Metal Compounds ◽  
X Ray
Sign in / Sign up

Export Citation Format

Share Document