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Chloride Monohydrate (chloride + monohydrate)
Selected AbstractsNanoparticles of CdCl2 with closed cage structuresISRAEL JOURNAL OF CHEMISTRY, Issue 1 2001Reshef Tenne Nanoparticles of various layered compounds having a closed cage or nanotubular structure, designated also inorganic fullerene-like (IF) materials, have been reported in the past. In this work IF -CdCl2 nanoparticles were synthesized by two methods. In one technique, a high temperature evaporation and subsequent condensation of dried cadmium chloride powder was used. In the other method, electron beam irradiation of the source powder led to its recrystallization into closed nanoparticles with a nonhollow core. The two methods are shown to produce nanoparticles of different topologies. While mostly spherical nested structures are obtained from the high temperature process, polyhedra with hexagonal or elongated rectangular characters are obtained by the electron beam induced process. The analysis also shows that, while the source (dried) powder is orthorhombic cadmium chloride monohydrate, the crystallized IF cage consists of the anhydrous 3R polytype which is not stable as bulk material in ambient atmosphere. Consistent with previous observations, this study shows that the seamless structure of the IF materials can stabilize phases, which are otherwise unstable in ambient conditions. [source] Physicochemical interactions between drugs and superdisintegrantsJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 12 2008Nelly Fransén We have evaluated the interactions between superdisintegrants and drugs with different physicochemical characteristics, which may affect the in-vivo absorption e.g. after mucosal administration. The binding of sodium salicylate, naproxen, methyl hydroxybenzoate (methylparaben), ethyl hydroxybenzoate (ethylparaben), propyl hydroxybenzoate (propylparaben), atenolol, alprenolol, diphenhydramine, verapamil, amitriptyline and cetylpyridinium chloride monohydrate (CPC) to different superdisintegrants (sodium starch glycolate (SSG), croscarmellose sodium (CCS) and crospovidone) and one unsubstituted comparator (starch) was studied spectrophotometrically. An indication of the in-vivo effect was obtained by measuring the interactions at physiological salt concentrations. SSG was investigated more thoroughly to obtain release profiles and correlation between binding and ionic strength. The results showed that the main interactions with the anionic hydrogels formed by SSG and CCS were caused by ion exchange, whereas the neutral crospovidone exhibited lipophilic interactions with the non-ionic substances. The effect of increased ionic strength was most pronounced at low salt concentrations and the ion exchange interactions were almost completely eradicated at physiological conditions. The release profile of diphenhydramine was significantly affected by the addition of salt. It was thus concluded that the choice of buffer was of great importance for in-vitro experiments with ionic drugs. At physiological salt concentrations the interactions did not appear to be strong enough to influence the in-vivo bioavailability of any of the drug molecules. [source] 2-Amino-4-(piperidin-1-yl)-11H -pyrimido[4,5- b][1,5]benzodiazepin-6-ium chloride monohydrate and 2-amino-4-[methyl(2-methylphenyl)amino]-11H -pyrimido[4,5- b][1,5]benzodiazepin-6-ium chloride,benzene-1,2-diamine (1/1): complex sheets generated by multiple hydrogen bondsACTA CRYSTALLOGRAPHICA SECTION C, Issue 4 2010Jairo Quiroga In each of 2-amino-4-(piperidin-1-yl)-11H -pyrimido[4,5- b][1,5]benzodiazepin-6-ium chloride monohydrate, C16H19N6+·Cl,·H2O, (I), and 2-amino-4-[methyl(2-methylphenyl)amino]-11H -pyrimido[4,5- b][1,5]benzodiazepin-6-ium chloride,benzene-1,2-diamine (1/1), C19H19N6+·Cl,·C6H8N2, (II), the seven-membered ring in the cation adopts a boat conformation. The pyrimidine ring in (II) adopts a twist-boat conformation, but the corresponding ring in (I) is essentially planar. The amino groups of the benzene-1,2-diamine component of (II) are both pyramidal. The independent components of (I) are linked into complex sheets by a combination of N,H...O, N,H...N, N,H...Cl and O,H...Cl hydrogen bonds. In the crystal structure of (II), one N,H...N hydrogen bond and six independent N,H...Cl hydrogen bonds combine to link the components into complex sheets. [source] Clindamycin hydrochloride monohydrate and its ethanol solvateACTA CRYSTALLOGRAPHICA SECTION C, Issue 2 2010Krishnan Ravikumar Clindamycin hydrochloride, an antibiotic of the lincomycin family, was crystallized as the monohydrate, namely (2S,4R)-2-(N -{(1S,2S)-2-chloro-1-[(3R,4S,5R,6R)-3,4,5-trihydroxy-6-(methylsulfanyl)perhydropyran-2-yl]propyl}aminocarbonyl)-4-propylpyrrolidinium chloride monohydrate, C18H34ClN2O5S+·Cl,·H2O, (I), and as the monohydrate ethanol solvate, C18H34ClN2O5S+·Cl,·H2O·C2H6O, (II). The conformation of the clindamycin molecule in both crystal structures is the same and is found to be similar to that in enzyme-bound clindamycin. The simultaneous presence of free chloride ions and water molecules in (I) and of additional ethanol molecules in (II) provides an interesting network of hydrogen bonds. The significance of this study lies in the interactions in these structures and the aggregations occurring via hydrogen bonds in the hydrated and solvated crystalline forms of the title compound. [source] 7-Methoxy-2,3-dioxo-1,4-dihydroquinoxalin-6-aminium chloride monohydrateACTA CRYSTALLOGRAPHICA SECTION C, Issue 1 2010Jürgen Brüning Single crystals of the title compound, C9H10N3O3+·Cl,·H2O, were obtained by recrystallization from hydrochloric acid. The cations stack along the crystallographic a direction. The 2,3-dioxo-1,4-dihydroquinoxaline group shows a significant deviation from planarity [r.m.s. deviation from the best plane = 0.063,(2),Å]. Hydrogen bonding links the cations, chloride anions and water molecules to form an extended three-dimensional architecture. [source] Hydrogen bonding in two salts of 3-methylthio-4-(propargylthio)quinolineACTA CRYSTALLOGRAPHICA SECTION C, Issue 9 2000Stanis, aw Boryczka In 3-methylthio-4-(propargylthio)quinolinium chloride monohydrate, C13H12NS2+·Cl,·H2O, and 3-methylthio-4-(propargylthio)quinolinium trichloroacetate, C13H12NS2+·C2Cl3O2,, the terminal alkyne group forms C[triple-bond]C,H,O hydrogen bonds of favourable geometry. The conformation of the flexible propargylthio group is different in the two structures. [source] Preparation of bioadsorbents for effective adsorption of a reactive dye in aqueous solutionASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING, Issue 4 2010Shariff Ibrahim Abstract The surface of barley straw, an agricultural waste, was modified chemically using a cationic surfactant hexadecylpyridinium chloride monohydrate (CPC) and used as an adsorbent for removal of Reactive Blue 4 (RB4) from aqueous solution. The raw and surfactant-modified barley straws (SMBS) were characterized by Fourier transform infrared and elemental analysis. The stability of CPC adsorbed on straw surface was evaluated by exposing to water and organic solvents. The adsorption was performed on removing RB4 from wastewater in a batch adsorption system. The effects of contact time, initial concentration of dye and pH of solution on RB4 uptake were investigated and discussed. It was found that the removal percentage of RB4 increased with the increase in contact time. Adsorption was favorable at acidic condition and the maximum removal of 100% was obtained at pH 3. Dye-loaded SMBS was stable and percentage of desorption was less than 7% in water. The kinetic studies revealed that the kinetic data fitted well to the pseudo-second-order model. The isotherm study also indicated that RB4 adsorption on SMBS matched well with the Langmuir model other than the Freundlich model. The maximum adsorption capacity determined from the Langmuir isotherm was 29.2 mg g,1 at 25 °C. Copyright © 2010 Curtin University of Technology and John Wiley & Sons, Ltd. [source] | ||||||||||