Anhydrous Acetate Research Articles

Acetylation of Emodin and Cytotoxic Activity Effect Against HepG2 Cell Lines

Emodin (1,3,8-trihydroxy-6-methyl-9,10-anthraquinone) is an anthraquinone bioactive compound used as a lead compound because it exhibits potential anticancer properties. Structural modifications were made at the C3 position and its relationship to cytotoxic activity against the HepG2 cell line to determine the pharmacophore group of this compound. The hydroxy group at C3 emodin is converted to an ester group to produce 3-acetyl emodin. In addition, docking simulations into the cancer target protein casein kinase-2 were also carried out to predict molecular interactions. Emodin was reacted with anhydrous acetate and confirmed the product confirmation using LCMS/MS, FTIR, 1H-NMR, and 13C-NMR. Emodin and 3-acetyl emodin were tested for cytotoxicity against HepG2 cells in vitro. Cytotoxic emodin and 3-acetyl emodin tests on HepG2 cells resulted in Cytotoxic concentrations 50 (CC50) of 0.54 mM and 0.42 mM, respectively. The results showed that modifying the C3 hydroxyl group with acetyl can increase the cytotoxic effect more than emodin. This research is expected to provide information regarding the structure-activity relationship of emodin in cancer cells and the expansion of new drug applications for additional cancers.

Significance of Hydroxyl Groups on the Optical Properties of ZnO Nanoparticles Combined with CNT and PEDOT:PSS.

We report on the synthesis of ZnO nanoparticles and their hybrids consisting of carbon nanotubes (CNT) and polystyrene sulfonate (PEDOT:PSS). A non-aqueous sol–gel route along with hydrated and anhydrous acetate precursors were selected for their syntheses. Transmission electron microscopy (TEM) studies revealed their spherical shape with an average size of 5 nm. TEM also confirmed the successful synthesis of ZnO-CNT and ZnO-PEDOT:PSS hybrid nanocomposites. In fact, the choice of precursors has a direct influence on the chemical and optical properties of the ZnO-based nanomaterials. The ZnO nanoparticles prepared with anhydrous acetate precursor contained a high amount of oxygen vacancies, which tend to degrade the polymer macromolecule, as confirmed from X-ray photoelectron spectroscopy and Raman spectroscopy. Furthermore, a relative increase in hydroxyl functional groups in the ZnO-CNT samples was observed. These functional groups were instrumental in the successful decoration of CNT and in producing the defect-related photoluminescence emission in ZnO-CNT.

LiYF4:Yb/LiYF4 and LiYF4:Yb,Er/LiYF4 core/shell nanocrystals with luminescence decay times similar to YLF laser crystals and the upconversion quantum yield of the Yb,Er doped nanocrystals

We developed a procedure to prepare luminescent LiYF4:Yb/LiYF4 and LiYF4:Yb,Er/LiYF4 core/shell nanocrystals with a size of approximately 40 nm revealing luminescence decay times of the dopant ions that approach those of high-quality laser crystals of LiYF4:Yb (Yb:YLF) and LiYF4:Yb,Er (Yb,Er:YLF) with identical doping concentrations. As the luminescence decay times of Yb3+ and Er3+ are known to be very sensitive to the presence of quenchers, the long decay times of the core/shell nanocrystals indicate a very low number of defects in the core particles and at the core/shell interfaces. This improvement in the performance was achieved by introducing two important modifications in the commonly used oleic acid based synthesis. First, the shell was prepared via a newly developed method characterized by a very low nucleation rate for particles of pure LiYF4 shell material. Second, anhydrous acetates were used as precursors and additional drying steps were applied to reduce the incorporation of OH− in the crystal lattice, known to quench the emission of Yb3+ ions. Excitation power density (P)-dependent absolute measurements of the upconversion luminescence quantum yield (ΦUC) of LiYF4:Yb,Er/LiYF4 core/shell particles reveal a maximum value of 1.25% at P of 180 Wcm−2. Although lower than the values reported for NaYF4:18%Yb,2%Er core/shell nanocrystals with comparable sizes, these ΦUC values are the highest reported so far for LiYF4:18%Yb,2%Er/LiYF4 nanocrystals without additional dopants. Further improvements may nevertheless be possible by optimizing the dopant concentrations in the LiYF4 nanocrystals.

Study on the Different Method of Extraction of Star Anise Oil

The three reagents of anhydrous ethanol, petroleum ether and ethyl acetate were selected by soxlet extraction, steam distillation and ultrasonic extraction to extract the star anise oil from the fine anise powder. Three kinds of methods for extracting star anise oil were studied on different pattern organic solvent. The result of the different volume fractions of ethanol is that the highest extraction rate is 99.7% ethanol. It can be seen that the extraction rate are: ethanol > petroleum ether > acetic acid ethyl ester. The different methods of extracting the star anise oil shows that the extraction rate are: soxhlet extraction method > ultrasonic extraction method > steam distillation extraction method. In summary, it can be seen by soxhlet extraction method and the best solvent is 99.7% ethanol.

Synthesis of Anhydrous Acetates for the Components of Nuclear Fuel Recycling in Dialkylimidazolium Acetate Ionic Liquids.

A series of anhydrous acetate salts with uranium {[C2C1im][UO2(OAc)3] (1), [C2C2im][UO2(OAc)3] (2), and [C4C1im][UO2(OAc)3] (3)}, lanthanides {[C2C2im]2[La(OAc)5] (4) and [C2C1im]2[Nd(OAc)5] (5)}, and strontium {[C2C1im]n[Sr(OAc)3]n (6)} (where C2C1im = 1-ethyl-3-methylimidazolium, C2C2im = 1,3-diethylimidazolium, C4C1im = 1-butyl-3-methylimidazolium, and OAc = acetate) have been prepared and structurally characterized. Both lanthanides and strontium are common components of the nuclear fuel waste, and their separation from uranium is an important but still challenging task. A new synthetic approach with dialkylimidazolium acetate ionic liquids (ILs) as the solvent has been developed for the direct synthesis of homoleptic acetates from the corresponding hydrates and, unexpectedly, hardly soluble f-element oxides. Although the group of characterized compounds shows perfect structural variability, all actinide and lanthanide metal ions form monomeric complex anions where the metal cation coordinates to five ligands including two oxygen atoms in the case of uranium, as is commonly observed for uranyl compounds. Crystallographic analyses revealed that the complex [UO2(OAc)3]- anions possess rather standard D3h symmetry featuring a hexagonal-bipyramidal coordination environment, while the lanthanide anions [Ln(OAc)5]2- are fully asymmetric and the Ln3+ cations are 10-coordinated in the form of a distorted bicapped tetragonal antiprism. This is the first report of lanthanide ions coordinated in this fashion. For Sr2+, 9-fold coordination through oxygen atoms in the form of a strongly distorted tricapped trigonal prism is observed. The crystallization of anhydrous, homoleptic, anionic acetate complexes from such a large variety of different metal salts appears to be due to the properties of dialkylimidazolium acetate ILs themselves, including enhanced basicity from the high concentration of free anions and their greater affinity for hydrogen-bonding solutes relative to metal cations.

Synthesis of Nanocrystalline SnxCd1−xS Thin Films Capped with Thioglycerol and Methanol (TGM) and Study of Optical and Structural Properties

Nanostructured CdS (nCdS) and ternary SnxCd1−xS thin films capped with thioglycerol and methanol in 1:1 ratio in aqueous medium were prepared using hydrated stannous chloride (SnCl2·2H2O), anhydrous cadmium acetate (CH3COO)Cd·2H2O and thiourea (CS(NH2)2) as sources of Sn, Cd and S ions, respectively. Thickness of the film drastically decreases for low concentrations (0–2%) of Sn doping, then increases for (2–3%) and 5% Sn doping. Effects of Sn concentration variation on the optical properties, photoluminescence and structural properties of the nanoparticles were studied. The optical transmittance measurement using ultraviolet–visible–near infrared spectroscopy showed more than 80% transparency in the wavelength range 450–800 nm for 3% and 5% Sn doping. The direct optical band gap value of nanoCdS thin films was obtained as 2.91 eV, which decreased with Sn doping for its varying concentrations. Photoconductivity gain was negligible. A decrease in intensity of lower wavelength emission at 430 nm in nCdS was observed to have (2–5)% Sn content. X-ray diffraction patterns and selected area electron diffraction patterns confirmed formation of the nanocrystalline hexagonal CdSnS phase. Scanning electron microscope and transmission electron microscope measurements of the CdSnS thin films show that the particle size lies well under 20 nm.

Genesis of nanocrystalline Ho2O3 via thermal decomposition of holmium acetate: Structure evolution and electrical conductivity properties

This study focuses on the preparation of nanostructured holmium oxide via the decomposition of holmium acetate precursor utilizing the non-isothermal strategy. Thermogravimetric analysis (TGA) was used to follow up the various thermal events involved in the decomposition process. Dehydration completes approximately at 150 °C, which is followed by the decomposition of the anhydrous acetate leading to the formation of holmium oxide. Based on the TGA results the acetate precursor was heated non-isothermally at the temperature range of 150–700 °C. The obtained solids were characterized using powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR), field-emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM). It is found that nanocrystalline Ho2O3 starts to form at 500 °C and presents the only phase detected at the 500–700 °C range. The electrical conductivity of the solids that form at the temperature range of 300–700 °C was investigated. The obtained values were correlated with the observed structural modifications accompanying the heat treatment. The electrical conductivity of the Ho2O3 samples prepared at 500, 600 and 700 °C reaches the values of 1.92 × 10−7, 1.61 × 10−7 and 8.33 × 10−8 Ω−1·cm−1 at a measuring temperature of 500 °C, respectively. These values are potentially advantageous for high-resistivity devices.

Synthesis of cellulose acetate from palm oil bunches and dried jackfruit leaves

Cellulose acetate is a natural polymer, that is widely used in various industries, especially fiber and plastics. Cellulose acetate was created by an esterification reaction of cellulose and acetic anhydride. The raw materials used in this research were empty fruit bunches of palm oil and dried jackfruit leaves, because utilization of waste, available in large quantities, and contain high cellulose. The objective of this study was to obtain high yield cellulose and cellulose acetate from palm oil bunches and jackfruit leaves. This was done by variating delignification time, bleaching time, and acetylation time. Cellulose isolation was performed through a delignification process by adding NaOH and bleaching process by adding H2O2. The optimum yield for the empty palm oil bunches cellulose was 36.45%, with the delignification time of 1.5 hours and the bleaching time of 30 minutes. The optimum yield of jackfruit leaves cellulose was 13.72%, with 1-hour delignification time and 30 minutes bleaching time. Cellulose acetate was obtained by cellulose activation process by adding acetic acid glacial, acetylation process with anhydrous acetate, and hydrolysis with water. The yield of cellulose acetate obtained was 81.75% for palm oil bunches and 63.89 for jackfruit leaves.

Investigation into the Palladium‐Europium Acetate Reductive Decomposition with Synchrotron Radiation‐Based X‐ray Diffraction and X‐ray Absorption Spectroscopy

AbstractThe reductive decomposition of the complex Pd2Eu2(μ,η2‐OOCMe)2(μ‐OOCMe)8(H2O)2·(HOOCMe)2upon heating from room temperature to 500 °C in a hydrogen atmosphere was investigated by in situ synchrotron radiation‐based X‐ray absorption fine structure spectroscopy (XAFS) including observations of X‐ray near‐edge structure (XANES) and extended absorption fine structure (EXAFS) at Pd K‐ and Eu L3‐edges and synchrotron X‐ray diffraction (XRD). The Pd‐Eu2O3nanocomposite was found to be the final thermolysis product. The decomposition proceeds via series of intermediate crystalline phases, including europium(II) and (III) anhydrous acetates and EuO(CH3COO) oxidoacetate. Surprisingly, the major fraction of europium occurs in the reduced form Eu2+within a limited temperature range of 200–300 °C. Presumably, the reversible Eu3+↔Eu2+redox‐process is associated with the stability of nanocrystalline palladium hydride, which acts as a stronger reducing agent as compared to molecular hydrogen.

Research and development of method for potassium acetate of high purity

Crystallization of potassium acetate from aqueous solutions, an effect of product yield and washing of its crystals on an efficiency of purification were investigated. Behavior of KCH3COO·1.5H2O was studied in heating. Based on data of the study a technological scheme of producing anhydrous potassium acetate of high purity was developed.

Structure of reaction products of hydrous and anhydrous zinc acetates with 1,10-phenanthroline

A reaction of aqueous zinc acetate with 1,10-phenanthroline produces the ionic complex [(Phen)2Zn(OOCMe)](OOCMe) · 5H2O. A similar reaction of “anhydrous zinc acetate” [Zn7(μ4-O)2(μ-OOCMe)10][η-OC(Me)OHNEt3]2 in benzene yields a precipitate, which is recrystallized from acetonitrile into trinuclear (Phen)2Zn3(μ-OOCMe)6; and the reaction in acetonitrile yields mononuclear (Phen)Zn(OOCMe)2 · MeCN. These complexes have been characterized by single-crystal X-ray diffraction.

α-[Mn(O2CMe)2]: a two-dimensional coordination polymer of the anhydrous manganese acetate polymorphs

Two polymorphs of crystalline anhydrous manganese acetate, α-[Mn(O2CMe)2] (1) and β-[Mn(O2CMe)2] (2), were prepared under temperature-controlled solvothermal dehydration. X-ray single-crystal (and powder) diffractions revealed that compound 1 crystallizes in monoclinic (a = 9.763(4), b = 4.972(2), c = 6.122(3) A, β = 102.878(5)°, V = 289.7(2) A3, Z = 4) space group P2/c. Although it was early prepared, its single crystal structure is firstly determined and known as a two-dimensional (2D) layer structure; whereas, compound 2 demonstrates a three-dimensional diamondoid (dia-e) structure that people in its early X-ray single-crystal study was not aware of. Anhydrous α-[Mn(O2CMe)2] was discovered in 1967, which two-dimensional layer structure is firstly determined by the X-ray single-crystal analysis.

γ-Irradiation effects on the kinetics and mechanism of the thermal decomposition of silver acetate

The kinetics of the thermal decomposition of un-irradiated (pristine) and pre-γ-irradiated anhydrous silver acetate was studied in the temperature range (298–773 K) and in air using isothermal and dynamic thermogravimetric techniques. The data were analyzed using various solid-state reaction models. An integral method using the Coats–Redfern equation was applied in dynamic data analysis. The results showed that the kinetics of isothermal decomposition for the acceleratory stage was governed by a diffusion-controlled process while in non-isothermal (dynamic) decomposition the kinetics were controlled by a nucleation process. The activation energies of the main decomposition process for un-irradiated and pre-γ-irradiated samples were calculated and the results of the isothermal and dynamic integral methods were compared and discussed. The changes in texture and crystal structure of the investigated silver acetate by γ-irradiation were studied using electron microscopy and X-ray diffraction techniques.

One-Pot Synthesis of α-Aminophosphonates on Silica under Solvent-Free Conditions from Aromatic Aldehydes

α-Aminophosphonates were synthesised under solvent-free conditions on an acidic silica gel support using aromatic aldehydes, diethyl phosphite and anhydrous ammonium acetate as starting materials in moderate yields

Crystal structure of imidazolium decanedioate, C18H31N2O6

Abstract C18H31N2O6, triclinic, P1̅(No. 2), a = 8.8249(8) Å, b = 8.992(2) Å, c = 12.897(2) Å, α = 95.22(1)°, β = 92.91(1)°, γ = 94.62(1)°, V = 1014.1 Å3, Z = 2, Rgt(F) = 0.042, wRref(F2) = 0.124, T = 293 K.

Adhesives for seed placement during artificial inoculation of Pinus banksiana seedlings with the dwarf mistletoe Arceuthobium americanum

Lodgepole pine dwarf mistletoe (Arceuthobium americanum Nutt. ex Engelm.) is a serious pest of jack pine (Pinus banksiana Lamb.). Research investigating factors such as host resistance, influence of host nutrition on infection rates, and effect of temperature and humidity on the life cycle of the pathogen is limited by our ability to consistently infect the host through artificial means. A greenhouse experiment utilizing a completely randomized design with four replicates was conducted to test the effectiveness of three chemical compounds and the natural viscin of the dwarf mistletoe seed to act as adhesives during artificial inoculation of jack pine seedlings. Synthetic adhesives used were anhydrous lanolin (LAN), hydroxypropylcellulose (HPC), and polyvinyl acetate (PVA). The percentage of infected seedlings was significantly higher with HPC compared with that of PVA, LAN, and the seed's viscin. HPC, as the superior adhesive, and the techniques described should allow consistent production of seedlings infected with dwarf mistletoe for research, regardless of the dwarf mistletoe species involved. Problems encountered during the testing of the adhesives are discussed in relation to the nature of the adhesives and their application.Key words: anhydrous lanolin, hydroxypropylcellulose, polyvinyl acetate, viscin.

Thermal decomposition of cerium(III) acetate studied with sample-controlled thermogravimetric–mass spectrometry (SCTG—MS)

Abstract Thermal decomposition of cerium(III) acetate hydrate, Ce(CH 3 CO 2 ) 3 ·1.5H 2 O, to cerium(IV) oxide, CeO 2 , in helium has been successfully investigated by sample-controlled thermogravimetry combined with evolved gas analysis by mass-spectrometry (SCTG–MS). Cerium(III) anhydrous acetate decomposed to cerium (IV) oxide through four decomposition steps in the temperature range of 250–800 °C. SCTG–MS was very useful to distinguish the successive decomposition accompanying the formation of the intermediate products to identify simultaneous gas evolution during the mass losses. The decomposition intermediates quenched from SCTG were characterized by X-ray diffraction (XRD) and X-ray absorption near-edge structure (XANES). The XANES revealed clearly the coexistence of Ce(III) and Ce(IV) and the valence change from cerium(III) to cerium(IV). The three decomposition intermediate products were presumed to be Ce 2 O(CH 3 CO 2 ) 4 , Ce 2 O 2 (CH 3 CO 2 ) 2 and Ce 2 O 2 CO 3 . A detailed thermal decomposition mechanism of Ce(CH 3 CO 2 ) 3 ·1.5H 2 O is discussed.

Thermal Decomposition of Cerium(III) Acetate Hydrate by a Three-dimensional Thermal Analysis

The thermal decomposition of cerium(III) acetate hydrate, Ce(CH3CO2)3·1.5H2O, in helium was successfully studied by the simultaneous measurement of TG-DTA and EGA by mass spectrometry (TG-DTA-MS) as well as that of X-ray diffractometry: DSC (XRD-DSC). TG-DTA-MS was useful to elucidate the complicated successive reactions accompanying the formation of intermediate products. Crystalline cerium(III) anhydrous acetate appeared at 212°C and transformed to another phase at 286°C. Cerium(III) anhydrous acetate decomposed in the temperature range of 300 - 700°C to cerium(IV) oxide via four decomposition steps; the chemical compositions of the three decomposition intermediate products were presumed to be Ce2O(CH3CO2)4, Ce2O2(CH3CO2)2 and Ce2O2CO3. The endothermic dehydration and the exothermic crystallization were characterized by simultaneous XRD-DSC. It has been demonstrated that cerium(III) changed to cerium(IV) in the final step. A detailed decomposition mechanism of Ce(CH3CO2)3·1.5H2O is discussed.

Thermoanalytical investigations of the decomposition course of copper oxysalts

The thermal decomposition course of copper acetate monohydrate (CuAc) was examined on heating up to 600°C at various rates, by TG, DTA and DSC. Non-isothermal kinetic and thermodynamic parameters were determined in air or nitrogen. SEM was used to describe the decomposition course and the solid products were identified by IR and XRD analysis. The results indicated that CuAc was dehydrated at 190°C and then partially decomposed at 220°C, giving rise to CuO in addition to a minor portion of Cu2O and Cu4O3. The last two oxides seemed to facilitate the decomposition of the rest of the anhydrous acetate. Cu2O and Cu4O3 were oxidized in air at >400°C, in a process that did not occur in nitrogen.

Quantitative anodic generation of cobalt (III) at glassy carbon in acetic acid. Coulometric titrations with the generated reagent

Conditions are established for quantitative electrochemical generation of cobalt (III) at a glassy carbon working electrode in anhydrous acetic acid in the presence of potassium acetate, sodium acetate or sodium perchlorate. In anhydrous alkali-metal acetate solutions cobalt (III) is as stable as in the presence of acetic anhydride. The concentration of cobalt(III) in the solution is considerably decreased in the presence of small amounts of water. This phenomenon is much more pronounced in sodium perchlorate supporting electrolyte. Coulometric titration methods for the determination of hydroquinone, 2-methylhydroquinone and ascorbic acid with the generated oxidant have been developed. The errors of the determinations are less than ±2%.