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1.
In this work, the calcium phosphate nanoparticles have been produced by new reverse micro emulsion method containing β‐cyclodextrin, poly(oxyethylene)5 nonyl phenol ether and cyclohexane. Scanning electron microscope, transmission electron microscope, fourier transform infrared spectroscope and X‐ray diffraction were used to characterize the particles. The sizes of the nanoparticles were identified between 70‐80 nm. In conclusion, these results suggested that the developed reverse micro emulsion system based nanoparticles seem to be a promising formulation for calcium phosphate nanoparticles synthesis and it has immense potential in delivery of drugs and vaccines.  相似文献   
2.
The 1:1 cocrystal of 2-amino-3-bromopyridine (2A3BP) with 4-methylbenzoic acid (4MBA) has been prepared by slow evaporation method in methanol, which was crystallized in monoclinic P21/c space group having two molecules in the asymmetric unit. The cocrystal has been characterized by single crystal X-ray analysis, FTIR, 1H NMR, 13C NMR, and Powder XRD. Theoretical investigations have been calculated by HF and density function (B3LYP) method with the 6-311+G(d,p) basis set. The vibrational frequencies together with the 1H NMR and 13C NMR chemical shifts have been calculated on the fully optimized geometry of 1. Theoretical calculations of bond parameters, harmonic vibration frequencies, and isotropic chemical shifts are in good agreement with the experimental results. Solvent-free formation of these cocrystal was confirmed by powder X-ray diffraction analysis. The crystal structure was stabilized by Npyridine—H···O = C, C = O—H···Npyridine and C—H···Br hydrogen bonding interactions.  相似文献   
3.
 Upon aging, perborate in glacial acetic acid generates peracetic acid and thus oxidizes S-phenylmercaptoacetic acid rapidly. Perborate dissolved in ethylene glycol, however, does not show the aging effect, and the corresponding oxidation proceeds smoothly. The oxidation is of second order and not acid catalyzed. Boric acid and borate do not influence the oxidation. In the smooth oxidation, is the reactive species. The oxidation of some para-substituted S-phenylmercaptoacetic acids conforms to the Exner relationship, indicating operation of a common mechanism. Also, the oxidation obeys the Hammett equation with a negative reaction constant. However, the oxidation of p-nitro-S-phenylmercaptoacetic acid follows a different kinetic pathway.  相似文献   
4.
In the crystal structures of 2‐amino‐4,6‐dimethoxypyrimidinium 2,4,6‐trinitrophenolate (picrate), C6H10N3O2+·C6H2N3O7, (I), and 2,4‐diamino‐5‐(4‐chlorophenyl)‐6‐ethylpyrimidin‐1‐ium (pyrimethaminium or PMN) picrate dimethyl sulfoxide solvate, C12H14ClN4+·C6H2N3O7·C2H6OS, (II), the 2‐amino‐4,6‐dimethoxypyrimidine and PMN cations are protonated at one of the pyrimidine N atoms. The picrate anion interacts with the protonated cations through bifurcated N—H...O hydrogen bonds, forming R21(6) and R12(6) ring motifs. In (I), Z′ = 2. In (II), two inversion‐related PMN cations are connected through a pair of N—H...N hydrogen bonds involving the 4‐amino group and the uncharged N atom of the pyrimidine ring, forming a cyclic hydrogen‐bonded R22(8) motif. In addition to the pairing, the O atom of the dimethyl sulfoxide solvent molecule bridges the 2‐amino and 4‐amino groups on both sides of the paired bases, resulting in a self‐complementary …DADA… array of quadruple hydrogen‐bonding patterns.  相似文献   
5.
A simple and efficient metal‐free ethenolate transfer reaction has been elaborated in moderate‐to‐high yields from vinyl acetate. This reaction was accomplished by generation of potassium ethenolate, which was then reacted with homo and mixed anhydrides of aliphatic, aryl and heteroaryl acids, to yield the corresponding vinyl esters. The utility of thus generated vinyl esters was then probed by carrying out intramolecular Heck reactions to give isobenzofuran‐1(3H)‐one derivatives in excellent yields.  相似文献   
6.
A magnetic separator attached in a zig zag flow channel assembly has been fabricated to detect myoglobin on the micro particles. An anti‐myoglobin conjugated magnetic hybrid and myoglobin conjugated silica micro particles were prepared and used for myoglobin detection on channel. For the detections, the competitive assay principle was followed based on affinity interaction of anti‐myoglobin‐myoglobin. The caliberation curve was plotted based on the deposit percentage of myoglobin conjugated silica micro particles. The calibration curve of the myoglobin showed the linear range between 1 × 10?8 ‐ 5 × 10?11 (M) (R2 = 0.9944). The minimum detectable concentration was 300 pg/mL. Hence all that concludes that, the application of zig zag flow channel with magnetic separator has offered new, simple and rapid approach for detecting myoglobin in whole blood samples with in 30 min.  相似文献   
7.
The anti myoglobin conjugated iron oxide/ru(bpy)32+/silica, anti myoglobin conjugated rhodamine 6G/silica particles were prepared, and used for myoglobin detections. The anti myoglobin conjugated iron oxide/ru(bpy)32+/silica particles were mixed with myoglobin in the micro centrifuge tube. After 10 min, the magnetic separators were introduced to catch the myoglobin‐captured anti myoglobin/iron oxide/ru(bpy)32+/silica particles from the homogenous solutions. For sandwich assays, the anti myoglobin conjugated rhodamine 6G/silica particles were incubated. The concentration of myoglobin was quantified based on anti myoglobin conjugated rhodamine 6G/silica particles. The calibration curve of the myoglobin showed the linear range to be between 1 × 10?12 and 1 × 10?10 (M) (R2 = 0.9944). The minimum detectable concentration was 17.6 pg/mL. The fluorescence method offered the best way to determine myoglobin with a total analysis time of less than 30 min.  相似文献   
8.
9.
Abstract

Elettaria cardamomum (L.) Maton prestigiously called as Indian cardamom and is mostly cultivated in south India at higher altitudes ranging from 900 to 1400 msl. The chemical composition of dry capsules essential oil of the four distinct varieties was chemo-profiled by gas chromatography-mass spectrometry (GC-MS). Results revealed a higher concentration of major monoterpene 1, 8-Cineole ranging between 28.94% and 34.91% in PV 1 and PV 2 varieties respectively. Other monoterpenes like α-Pinene, Sabinene, Linalool, α-Terpineol and Nerol were present considerable quantities in all of the four cardamom varieties. Two sesquiterpenic constituents namely, ç-Elemene and 1,6,10-dodecatrien-3-ol (Nerolidol) were identified in all varieties. Three ester constituents were also obtained in PV 1 in which α-Terpinyl acetate (26.68%) exhibited as a major ester constituent followed by Ocimenyl acetate (0.80%) and E5-Dodecenyl acetate (0.30%). This is the first published report on the phytochemical concentration of recent varieties of Indian cardamom.

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10.
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