Acetate Hydrate Research Articles

Tetrakis(μ-benzoato-κ2O:O)bis{[4-(dimethylamino)pyridine-κN1]copper(II)}

The title compound, [Cu2(C(7)H(5)O(2))4(C(7)H(10)N(2))2], is a crystallographically centrosymmetric binuclear complex, with Cu atoms [Cu...Cu = 2.6982 (4) A] bridged by four benzoate ligands. Each of the Cu atoms in this bunuclear copper(II) acetate hydrate analogue is present in an approximately square-pyramidal environment, with four O atoms in a plane and the pyridine N atom at the apical site. Selected geometric parameters are compared with values for related tetrabenzoate complexes of copper(II).

Dynamic dielectric response of PLZT-P(VDF/TFE) nanocomposites

Dynamic dielectric relaxation of polymer P(VDF/TFE)(0.98/0.02) loaded with lead lanthanum zirconate titanate (Pb0.92La0.08)(Zr0.65Ti0.35)O3(PLZT 8/65/35) ceramic nanopowders was studied in the frequency range from 100 Hz to 1 MHz and at temperatures from 100 K to 450 K. The PLZT nanopowders were prepared by the sol-gel method using: lead(II)acetate trihydrate, lanthanum acetate hydrate, zirconium(IV)propoxide and titanium(IV)propoxide. The crystallization process of PLZT powders was monitored by means of XRD analysis (Philips PW 3710) using Cu-Kα radiation in the range 20° ≤ 2Θ ≤ 60°. The powders were analyzed before and after burning of the organic remains. The morphology observations of the powders were made using Hitachi S-4700 scanning electron microscope (SEM), and the grain size distributions were measured on a Zetasizer Nano ZS by the DLS method. The PLZT-P(VDF/TFE) composite samples of 0-3 connectivity were prepared from ceramic and polymer powders by the hot-pressing method. The volume fraction of the ceramics Θ amounted 0.1, 0.15 and 0.2. The dielectric response of the ceramics-polymer composite was found as a combination of the responses of pure polymer and the ceramics: (i) the addition of the PLZT ceramics increases the value of the dielectric permittivity ϵ, (ii) the composite shows the maximum of the permittivity coming from the PLZT ceramics, (iii) the dielectric absorption spectrum of the composites is dominated by the α-relaxation in pure polymer.

A novel low-temperature chemical solution route for straight and dendrite-like ZnO nanostructures

The straight and dendrite-like growths of ZnO have been completely and simply controlled by the status of ZnO seed instead of surfactant, template, oriented attachment, and ZnO buffer layer on the substrate in the chemical reaction synthesis of ZnO nanostructures. The monodisperse ZnO seeds, which are prepared by in situ quickly injecting the cool mixed zinc acetate and potassium hydrate ethanol solution into the hot matrix aqueous solution of zinc nitrate hydrate and diethylenetriamine at 95 °C, improve the straight growth and lots of uniform, straight, and single-crystalline ZnO nanorods with about 20–30 nm in diameter and 300 nm in length are achieved. While, the aggregated ZnO seeds, which are prepared by dropwise adding potassium hydrate ethanol solution into zinc acetate ethanol solution at 60 °C for 3 h, result in the dendrite-like growth and the bur-like ZnO nanostructures consisting of hundreds of nanorods with about 30–50 nm in diameter and several micrometers in length are formed. Furthermore, the approach presented here provides a simple, low-cost, environmental-friendly and high efficiency route to synthesize the high quality ZnO nanorods and bur-like ZnO nanostructures.

Egg White Synthesis and Photoluminescence of Platelike Clusters of CeO2 Nanoparticles

This paper reports the synthesis of platelike CeO2 nanoparticles by a simple, cost-effective, and environmentally friendly method using cerium(III) acetate hydrate and freshly extracted egg white (ovalbumin) in an aqueous medium. A platelike structure of CeO2 nanoparticles having the particle size of 6−30 nm was obtained by calcining the precursors in air at 400, 500, and 600 °C, for 2 h. Results from XRD, Raman spectroscopy, and SAED analysis indicated that the synthesized CeO2 nanoparticles have the fluorite structure of the bulk CeO2. All samples show a strong UV−vis absorption below 400 nm (3.10 eV) with a well-defined absorbance peak at around 284 nm (4.37 eV). The estimated direct band gaps are 3.61, 3.59, and 3.57 eV for the samples calcined at 400, 500, and 600 °C, respectively. These band gaps are 0.42, 0.40, and 0.38 eV higher than that of bulk CeO2, indicating the quantum confinement effect of the nanosize particles. The 400 and 500 °C calcined samples exhibited similar emission peaks of room-t...

Fabrication of porous ZnO nanostructures and morphology control

AbstractPorous ZnO nanostructures were easily fabricated by annealing and etching of as‐grown ZnO nanorods using an aqueous solution method at low temperature. The density of ZnO nanorods was changed by repetition of coating and drying of zinc acetate hydrate in ethanol. The annealing process is a very critical step to make porous ZnO nanorods because nano‐sized pore are formed at this step. Without annealing, pores could not be observed at the surface of ZnO nanorods. Furthermore, pore the size gets larger in etching steps following the annealing. The structural and optical properties for porous ZnO nanostructures were investigated using TEM and PL. Porous ZnO nanostructures were grown along the c‐axis and pores were distributed in the whole body. PL intensity was increased by annealing and etching. This is ascribed to the improved crystallinity and large surface area. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Synthesis of nano-hollow-shaped rare earth oxides by glycothermal treatment of rare earth acetates and subsequent calcination

The reaction of yttrium acetate hydrate in 1,2-propanediol (1,2-PG) at 300 °C yielded the products containing the acetate groups and the glycol moieties. The products decomposed into Y 2O 3 below 400 °C, and the thus-obtained Y 2O 3 samples had quite large surface areas (>200 m 2/g) and were comprised of crystalline nano-hollow spheres with the outer diameter of 7–18 nm and the inner diameter of 2–8 nm. Dy 2O 3, Er 2O 3 and Yb 2O 3 composed of nano-hollow spheres were also obtained by the glycothermal treatment and subsequent calcination.

The effect of fluoride treatment on titanium treated with anodic spark oxidation

This study examined the effect of fluoride on the surface characteristics of an anodized titanium implant. Commercial pure titanium plate 20mm×10mm×2mm in size, and discs 1.5 mm thick and 1.5 mm in diameter, were used. The prepared samples were polished with #200 to #1, 000 SiC papers and were then washed sequentially with distilled water, alcohol and acetone. Anodic oxidation was performed using a regulated DC power supply in an electrolyte containing a mixture of 0.015 M DL-α-glycerophosphate disodium salt hydrate (DL-α-GP) and 0.2 M calcium acetate hydrate (CA) with an electric current density of 30mA/cm2 and voltage ranging from 0 to 290 V. The specimens were divided into four groups and a fluoride treatment was carried out. Group 1 was thermally treated in a 0.05 M TiF3 solution at 90°C, Group 2 was electrochemically treated at 150 V in a 0.05 M TiF3 solution, Group 3 was electrochemically treated at 150 V in a 0.05 M NaF solution, and Group 4 was electrochemically treated at 150 V in a 0.05 M HF solution. A porous oxide layer containing pores 1–4 μm in size was observed on the surface treated with anodic oxidation. The diameter of the pores was higher in the protrusion areas than in the sunken areas. A significant amount of fluoride ions was released in the initial period, with small amounts being released continuously thereafter. The viability of MC3T3 cells was high when the fluoride ion concentration was 10 ppm, but decreased with further increases in the fluoride concentration. A six-week immersion test in simulated body fluid (SBF) showed dense HA crystals in the group immersed in 0.05 M TiF3 at 90°C, which indicated good biocompatibility.

Distribution of trace amounts of M 2+ ions during Co(CH 3COO) 2·4H 2O crystallization

Distribution coefficients (Henderson–Kraček, Khlopin), D 2/1, of trace amounts of Ni 2+, Mg 2+, Cu 2+, Zn 2+, Mn 2+, Cd 2+, Ca 2+, and Sr 2+ have been determined during crystallization of Co(CH 3COO) 2·4H 2O. Their dependencies on some properties of cocrystallizing salts (acetate hydrates) as well as cocrystallizing ions (M 2+) have been analyzed. The D 2/1 values are comprised in the range of 0.004( D Sr)–3.3( D Ni) but most of them are less than 0.06. This indicates that most of investigated M 2+ ions may be effectively removed in preparation of high-purity cobalt(II) salts. M 2+ ions for which | r C o 2 + − r M 2+ | / r C o 2 + > 0.05 , cocrystallize with Co(CH 3COO) 2·4H 2O only in slight degree ( D 2/1 < 0.06). Ions having electron configuration d 1–9 cocrystallize with Co(CH 3COO) 2·4H 2O on an average in the considerable greater degree than ions of electron configuration d 0 or d 10.

Carbonyl‐Containing Spirodihydrofurans in Reactions with Ammonium Acetate and Hydrazine Hydrate.

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Reaction of 3‐Arylaminobenzofuro‐, 3‐Arylaminobenzothieno‐, and 3‐Arylaminoindolo[2,3‐c]pyrylium Salts with Nucleophilic Reagents.

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Pyran-2-ones as Synthons for Pyridazine-3-carboxylic Derivatives. Oxidation of Nitrogen-Rich Compounds

The reaction of 6-(pyridin-2-yl)-2H-pyran-2-one (1) with hydrazine hydrate toward pyridazine derivatives was investigated. To elucidate the reaction pathway, an intermediary-formed α,δ-dihydrazonohydrazide derivative (3) was successfully isolated. Oxidations of the above compounds as well as of other pyridazine derivatives containing a carbohydrazido group, using ammonium cerium(IV) nitrate (CAN), thallium(III) nitrate trihydrate (TTN), or copper(II) acetate hydrate (CuDA), are also presented.

Carbonyl-containing spiro-dihydrofurans in reactions with ammonium acetate and hydrazine hydrate

It has been shown that 2-spiro(3-R-6,6-dimethyl-4-oxo-2,3,4,5,6,7-hexahydrobenzofuran)-2′-(5′, 5′-dimethylcyclohexane-1′,3′-diones) undergo conversions in reactions with ammonium acetate and hydrazine hydrate into substituted dihydropyridin-2-ones and tetrahydro-1,2-diazepin-7-ones respectively as a result of ring-opening of the spirodimedonyl fragment through the corresponding amides and hydrazides of δ-keto acids.

Complexes with lignin model compound vanillic acid. Two different carboxylate ligands in the same dinuclear tetracarboxylate complex [Cu 2(C 8H 7O 4) 2(O 2CCH 3) 2(CH 3OH) 2

Two copper(II) coordination compounds with vanillic acid C 8H 8O 4 ( 1), namely [Cu 2(C 8H 7O 4) 2(O 2CCH 3) 2(CH 3OH) 2] ( 2) and [Cu 2(C 8H 7O 4) 4(H 2O) 2] ( 3), were synthesized and characterized. Single crystals of 1– 3 were obtained and their crystal structures determined. The structure of 2 shows dinuclear cage structure of copper acetate hydrate type, however with two different carboxylates, acetates and vanillic acid anions, respectively. Both bridging anions are in pairs in trans orientation. Methanol molecules are apically coordinated (Cu–O7 2.160(2) Å), fulfilling square-pyramidal coordination sphere around both copper ions. The compound 2 decomposes outside mother-liquid (yielding [Cu 2(C 8H 7O 4) 2(O 2CCH 3) 2(H 2O) 2] ( 2a)) with the removal of methanol, but without significant change of the dicopper tetracarboxylate cage structure, as noticed by μ eff 1.48 BM for 2a. Similar was found also in the X-band EPR spectra with three signals H z1 , H ⊥2 and H z2 in the region from 0 to 600 mT. The structure of free vanillic acid 1 is composed of dimeric units of two molecules, connected by two parallel hydrogen bonds between carboxylate group of each other (O1–H⋯O2 2.642(3) Å), while the structure of 3 is of [Cu 2(O 2CCH 3) 4(H 2O) 2] type. Interestingly, an additional signal in the EPR spectra of 3 is found at 80 mT ( H ⊥1) at 298 and at 116 K, next to three signals H z1 , H ⊥2 and H z2 .

Chemical Solution Deposition of (Pb1−xCax)TiO3 Thin Films with x∼0.5 as New Dielectrics for Tunable Components and Dynamic Random Access Memories

Calcium lead titanate ((Pb,Ca)TiO3) thin films, with calcium contents of ∼50 at.%, have been prepared by chemical solution deposition (CSD). Different synthetic sol–gel methods have been used for the preparation of the precursor solutions. 1,3‐propanediol, OH(CH2)3OH, and water, H2O, were used as solvents. Lead (II) acetate trihydrate, Pb(OCOCH3)2·3H2O, and titanium di‐isopropoxide bis(acetylacetonate), Ti(OC3H7)2(CH3COCHCOCH3)2, were used as reagents of lead and titanium, respectively. Calcium was incorporated into the solutions as calcium acetate hydrate, Ca(OCOCH3)2·xH2O, or as calcium acetylacetonate hydrate, Ca(CH3COCHCOCH3)2·xH2O. Only the use of calcium acetate led to precipitate‐free solutions. Pb(II)–Ti(IV)–Ca(II) sols were obtained when calcium acetate was refluxed with the lead and titanium reagents in a diol–water solvent. These sols led to films with a homogeneous compositional profile. Solutions obtained by mixing a water solution of calcium acetate with a Pb(II)–Ti(IV) sol led to films with a heterogeneous compositional profile in which an interface between the film and the Pt bottom electrode is formed. The films derived from the Pb(II)–Ti(IV)–Ca(II) sols have values of dielectric constant at room temperature of ∼500, which, together with their low leakage currents, low dielectric losses, and tunability, make these films promising for dynamic random access memories and tunable devices.

Reaction of 3-Arylaminobenzofuro-, 3-Arylaminobenzothieno-, and 3-Arylaminoindolo[2,3-c]pyrylium Salts with Nucleophilic Reagents

We have studied the reactions of 3-arylaminobenzofuro-, 3-arylaminobenzothieno-, and 3-arylaminoindolo[2,3-c]pyrylium salts with ammonium acetate, primary amines, and hydrazine hydrate. In an alcoholic medium, primary amines and hydrazine hydrate open up the pyrylium ring to form arylamides of 2-(N-benzylmethylketimine)hetaryl-3-acetic acids or the corresponding hydrazones, where further heterocyclization does not occur. Upon treatment with ammonium acetate in acetic acid, 2-aryl-1-methylhetero[2,3-c]pyridin-3-(2H)-ones are formed along with their 2-unsubstituted analogs.

Chemical variability of the essential oil ofHelichrysum faradifani Sc. Ell. from Madagascar

The combined analysis of a commercial sample of Helichrysum faradifani Sc. Ell. essential oil from Madagascar, using column chromatography, GC-RI, GC-MS and 13C-NMR, led to the identification of 47 components. The main constituents were α-fenchene (32.3%), γ-curcumene (19.4%), (E)-β-caryophyllene (14.2%), α-curcumene (2.9%), limonene (2.8%), lavandulyl acetate (2.1%) and α-fenchene hydrate (1.7%). The composition of this sample was quite different from that of a laboratory-distilled sample previously reported by our group. Moreover, none of the compositions reported in the literature for other Helichrysum oils exhibited a high content of α-fenchene. 13C-NMR data for exo-α-fenchene hydrate are reported. Copyright © 2005 John Wiley & Sons, Ltd.

Enantiomeric composition of (E)- and (Z)-sabinene hydrate and their acetates in ?veOriganum spp.

The enantiomers of (E)- and (Z)-sabinene hydrate and of (E)- and (Z)-sabinene hydrate acetate from extracts of Origanum ramonense Danin, O. dayi Post, O. majorana L., O. vulgare L. ssp. vulgare and O. syriacum L. ssp. syriacum were analysed by GC–MS with chiral and non-chiral capillary columns. The order of elution, the enantiomeric ratios and relative percentages of the four pairs of enantiomers were determined. The (1S)-enantiomers of (E)-sabinene hydrate and (E)-sabinene hydrate acetate were predominant in O. dayi, whereas in the other Origanum spp. the (1R)-enantiomers were predominant. (Z)-sabinene hydrate acetate was not detected in O. syriacum, while the (1R)-enantiomer was present in an optically pure form in O. ramonense, O. majorana and O. vulgare; in O. dayi the enantiomeric purity was 97%. The enantiomeric distributions of (E)- and (Z)-sabinene hydrate and their acetates were determined for the first time in Origanum spp. Copyright © 2004 John Wiley & Sons, Ltd.

Essential Oil Composition of Marjoram Cultivated in North of Iran

The essential oil was obtained by hydro distillation from the herb of marjoram (Majorana hortensis Möench) cultivated in the north of Iran. The oil content was 1.8% w/w based on dry weight. The oil was analyzed by capillary GC and GC/MS. A total of 24 components were identified by GC-MS analyses, the main components representing 99.2% of the oil was identified as terpinene-4-ol constituted (21.3%), trans-sabinene hydrate (14.8%), cis-sabinene hydrate acetate (10.7%), γ-terpinene (10.7%), α-terpinene (7.3%), sabinene (5.7%), α-terpineol (4.7%), cis-sabinene hydrate (4.5%), limonene (3.0%) linalyl acetate (3.0%) and terpinolene (2.6%). The results show that an acceptable content and composition of the oil is possible if marjoram is cultivated in north of Iran.

Microwave‐Induced Polyol‐Process Synthesis of Copper and Copper Oxide Nanocrystals with Controllable Morphology

AbstractDifferent morphologies of copper and copper oxide nanocrystallites, including radially arrayed whiskers, cubic particles and sphere particles, have been successfully synthesized by a microwave‐induced method under ambient conditions. In aqueous solution containing different ethylene glycol concentrations, copper acetate hydrate produces different reduction products. The as‐prepared copper and copper oxide crystallites were characterized by various techniques, including X‐ray powder diffraction, transmission electron microscopy, selected‐area electron diffraction and UV/Vis absorption spectroscopy. It was found that microwave irradiation plays a critical role in the formation of the products; temperature was also found to be important in the reaction. The irradiation time and copper acetate concentration also affect the morphology of the products. The possible formation mechanism is also discussed. ((c) Wiley‐VCH Verlag GmbH &amp; Co. KGaA, 69451 Weinheim, Germany, 2004)

Cyclic and acyclic compartmental Schiff bases, their reduced analogues and related mononuclear and heterodinuclear complexes

[1+1] macrocyclic and [1+2] macroacyclic compartmental ligands (H 2L), containing one N 2O 2, N 3O 2, N 2O 3, N 4O 2 or O 2N 2O 2 Schiff base site and one O 2O n ( n=3, 4) crown-ether like site, have been prepared by self-condensation of the appropriate formyl- and amine precursors. The template procedure in the presence of sodium ion afforded Na 2(L) or Na(HL) · nH 2O. When reacted with the appropriate transition metal acetate hydrate, H 2L form M(L) · nH 2O, M(HL)(CH 3COO) · nH 2O, M(H 2L)(X) 2 · nH 2O (M=Cu 2+, Co 2+, Ni 2+; X=CH 3COO −, Cl −) or Mn(L)(CH 3COO) · nH 2O according to the experimental conditions used. The same complexes have been prepared by condensation of the appropriate precursors in the presence of the desired metal ion. The Schiff bases H 2L have been reduced by NaBH 4 to the related polyamine derivatives H 2R, which form, when reacted with the appropriate metal ions, M(H 2R)(X) 2 (M= Co 2+, Ni 2+; X=CH 3COO −, Cl −), Cu(R) · nH 2O and Mn(R)(CH 3COO) · nH 2O. The prepared ligands and related complexes have been characterized by IR, NMR and mass spectrometry. The [1+1] cyclic nature of the macrocyclic polyamine systems and the site occupancy of sodium ion have been ascertained, at least for the sodium (I) complex with the macrocyclic ligand containing one N 3O 2 Schiff base and one O 2O 3 crown-ether like coordination chamber, by an X-ray structural determination. In this complex the asymmetric unit consists of one cyclic molecule of the ligand coordinated to a sodium ion by the five oxygen atoms of the ligand. The coordination geometry of the sodium ion can be described as a pentagonal pyramid with the metal ion occupying the vertex. In the mononuclear complexes with H 2L or H 2R the transition metal ion invariantly occupies the Schiff base site; the sodium ion, on the contrary, prefers the crown-ether like site. Accordingly, the heterodinuclear complexes [MNa(L)(CH 3COO) x ] (M=Cu 2+, Co 2+, Ni 2, x=1; M=Mn 3+, x=2) have been synthesised by reacting the appropriate formyl and amine precursors in the presence of M(CH 3COO) n · nH 2O and NaOH in a 1:1:1:2 molar ratio. The reaction of the mononuclear transition metal complexes with Na(CH 3COO) · nH 2O gives rise to the same heterodinuclear complexes. Similarly [MNa(R)(CH 3COO) x ] have been prepared by reaction of the appropriate polyamine ligand H 2R with the desired metal acetate hydrate and NaOH in 1:1:2 molar ratio.