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371.
Dhalwal K Shinde VM Namdeo AG Mahadik KR Kadam SS 《Journal of chromatographic science》2007,45(10):706-709
A simple, sensitive, and specific thin-layer chromatography densitometric method has been developed for the simultaneous quantitation of strychnine and brucine. These two marker compounds are quantitated in the seeds of Strychnos nux-vomica, Strychnos ignatii, and its formulations. The method involves densitometric evaluation of strychnine and brucine after resolving it by high-performance TLC on silica gel plate with toluene-ethyl acetate-diethyl amine-methanol (7:2:1:0.3 v/v) as the mobile phase. The method is validated for precision (interday and intraday), repeatability, and accuracy. The relationship between the concentration of standard solutions and the peak response is linear within the concentration range of 160 to 480 ng/spot for strychnine and 80 to 480 ng/spot for brucine. Instrumental precision is found to be 0.54 and 0.78 (% CV), and repeatability of the method is 1.01 and 1.06 (% CV) for strychnine and brucine, respectively. Accuracy of the method is checked by recovery study conducted at three different levels and the average percentage recovery is found to be 99.13% for strychnine and 100.16% for brucine. The proposed HPTLC method for the simultaneous quantitation of strychnine and brucine is found to be simple, precise, specific, sensitive, and accurate, and it can be used for routine quality control of raw material of Strychnos spp. It also can be applied in quantitating any of these marker compounds in other formulations. 相似文献
372.
As a new class of inorganic phosphor, orthophosphate phosphors materials have received great interest because of their potential applications in solid-state lightings and displays. In this article, we focus on current developments in the synthesis, crystal structure and luminescence properties of orthophosphate phosphors for solid-state lightings. We discuss the synthesis of a family of orthophosphate phosphor doped with europium (Eu2+ and Eu3+) by traditional and novel methods. In the fluorescent lamp, phosphor materials convert UV radiation into visible radiation. Lamp phosphors are mostly white in color and they should not absorb the visible radiation. New phosphors that can absorb excitation energy from blue or near ultraviolet (n-UV) LEDs and generate visible emissions efficiently are desired. The criteria of choosing the best phosphors, for blue (450–480 nm) and n-UV (380–400 nm) LEDs, strongly depends on the absorption and emission of the phosphors. Here, we will review the status of phosphors for solid-state lightings and prospect the future development. The impacts of doping of europium and photoluminescence properties on orthophosphate phosphors were investigated and we propose a feasible interpretation. 相似文献
373.
T. RameshR.S. Shinde S.R. Murthy 《Journal of magnetism and magnetic materials》2011,323(12):1593-1598
Modern accelerator design practice includes the use of high-quality ferrites for circulator applications with ever-increasing requirements on power handling ability. Modeling studies of new designs are of increasing economic importance, but are frequently hindered by lack of measured values of the ceramic loss factors. We have developed a nanocrystalline ferrite material with composition Ni0.94Co0.03Mn0.04Cu0.03Fe1.96O4. Nanocrystalline NiCoMnCu ferrite powders were synthesized using a microwave-hydrothermal method at 160 °C for 40 min. The ferrite formation conditions, such as pH, temperature and time, were optimized. The phase of the samples was identified by X-ray diffraction and was characterized by Fourier transformation infrared spectroscopy. The size of the nanocrystalline ferrite of as-synthesized powders was 10 nm. The powder was densified at different temperatures using a microwave sintering method. The complex permittivity and permeability of the sintered samples were measured over a frequency range from 10 kHz to 1.8 GHz at room temperature. The applicability of the samples for circulators was tested via the measurement of the ferromagnetic resonance linewidth and the results are presented. 相似文献
374.
Ramakrishna V. S. Nirogi Rama Sastri Kambhampati Prabhakar Kothmirkar Sobhanadri Arepalli Narasimha Reddy G. Pamuleti Anil K. Shinde 《合成通讯》2013,43(19):2835-2851
Abstract Several functionalized thienopyrimidines were synthesized by a facile synthetic method, which includes Gewald's reaction, and were characterized by spectral and analytical data. These functionalized thienopyrimidines were converted to various new chemical entities of biological importance, such as 2-piperazinymethyl thienopyrimidines (6, 8), 4-dimethylaminoethoxy thienopyrimidines (11), and 3-dimethylaminoethyl thienopyrimidines (12). All the compounds thus synthesized were screened for their invitro biological activities. Some of the compounds displayed promising serotonin 5-HT6 receptor antagonist activities.
ACKNOWLEDGMENT
The support received from the Discovery Analytical Department and Venkateswarlu Jasti, CEO, Suven Life Sciences Ltd., Hyderabad, is gratefully acknowledged. 相似文献375.
Shahul Hameed P. Gajanan Shanbhag Vikas Shinde Murugan Chinnapattu Praveena Manjrekar Jayashree Puttur 《合成通讯》2013,43(24):3315-3321
Short and efficient route for the synthesis of oxazinone- and thiazinone-containing bicyclic heteroaromatic aldehydes, which involves the key step of palladium-catalyzed reductive carbonylation, is described. Overall routes for the synthesis of these aldehydes are short, versatile, and scalable with good yields of the product. [Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.] 相似文献
376.
Ramhari V. Rote Deepak P. Shelar Sandeep R. Patil Santosh S. Shinde Raghunath B. Toche Madhukar N. Jachak 《Journal of fluorescence》2011,21(1):453-459
Novel pyrazolo-pyrrolo-pyrimidine (PPP) derivatives having remarkable photophysical properties are designed with the help of theoretical semiempirical calculations. These compounds then synthesized successfully and studied effect of substituents on its photophysical properties. Figure
377.
Ambrosini S Serra M Shinde S Sellergren B De Lorenzi E 《Journal of chromatography. A》2011,1218(39):6961-6969
Two series of molecularly imprinted polymers (MIPs) for the class-selective recognition of glucuronides have been prepared by using lipophilic substructures of the target analyte as template molecule and potent host monomers against oxyanions, that are expected to establish a strong stoichiometric interaction with the single carboxylic group of the template. The polymers were tested as stationary phases in liquid chromatography for specific recognition. A preliminary investigation of the imprinting properties of eleven MIPs was carried out, by comparing the retention time of the template and of structurally related compounds on the MIP column with that on the corresponding non-imprinted polymer (NIP). The two polymers showing the best performance were selected to further test cotinine, mycophenolic acid, testosterone and their respective glucuronides as model compounds. The high specificity obtained against glucuronides and the different chemical structure of the parent drug make the two MIPs class-selective imprinted receptors, also suitable for SPE application. 相似文献
378.
Synthesis and Antifungal Screening of 2‐(2‐Aryl‐4‐methyl‐thiazol‐5‐yl)‐5‐((2‐aryl/benzylthiazol‐4‐yl)methyl)‐1,3,4‐oxadiazole Derivatives 下载免费PDF全文
Pravin C. Mhaske Shivaji H. Shelke Kisan Gadge Abhijit Shinde 《Journal of heterocyclic chemistry》2016,53(1):129-134
A new series of synthesis and biological screening of 2‐(2‐aryl‐4‐methyl‐thiazol‐5‐yl)‐5‐((2‐aryl/benzylthiazol‐4‐yl)methyl)‐1,3,4‐oxadiazole derivatives 5a , 5b , 5c , 5d , 5e , 5f , 5g , 5h , 5i was achieved by condensation of 2‐(2‐aryl/benzylthiazol‐4‐yl)acetohydrazide 2a , 2b , 2c with 4‐methyl‐2‐arylthiazole‐5‐carbaldehyde 3a , 3b , 3c followed by oxidative cyclization of N'‐((4‐methyl‐2‐arylthiazol‐5‐yl)methylene)‐2‐(2‐aryl/benzylthiazol‐4‐yl)acetohydrazide 4a , 4b , 4c , 4d , 4e , 4f , 4g , 4h , 4i using iodobenzene diacetate as oxidizing agent. All the synthesized compounds were screened for their in vitro antifungal activity against Candida albicans, Candida tropicalis, Aspergillus niger, and Aspergillus flavus. Some of the synthesized compounds showed good antifungal activity. 相似文献
379.
Niobium (Nb) doped molybdenum trioxide (MoO3) thin films have been synthesized using spray pyrolysis deposition technique. The structural changes were observed with the help of X-ray diffraction technique. With increasing Nb concentration, the structure of MoO3 undergoes a phase transformation from α-orthorhombic to amorphous with nano-sized grains. The thread like reticulated morphology is converted into spongy like structure at higher Nb concentration (9 at% Nb). It is seen that Nb doping can lead to significant surface morphology changes in MoO3 films. It was found that the coloration efficiency increases with doping concentration. With increasing Nb concentration charge capacity, reversibility and electrochemical stability increases. The improvement is attributed to the amorphous structure of the doped samples that favors easy intercalation and deintercalation processes. Hence, we have successfully demonstrated formation of an adequate host for electrochromic devices with Nb (9 at%) doped MoO3 samples. 相似文献
380.
Clay minerals occur widely in nature and play a very important role in agriculture, mineral recovery and chemical manufacturing.
Among the many properties which affect clay behaviour, water binding and ion exchanging appear to be the most important. The
study of the cation exchange capacity of soils is of great theoretical and practical importance since the CEC determines in
many ways the behavior of nutrients, chemical amendments, and many toxic compounds entering the sols. Sorption interactions
with montmorillonite and other clay minerals in soils are potantially important mechanisms for attenuating the mobility of
heavy metal cations through the subsurface environment. In this work the cation exchange capacity (CEC) of montmorillonite
from west Anatolia, and sorptions with montmorillonite for attenuating the mobility of uranium were studied. The CEC value
was found to be 77 meq/100 g montmorillonite. The relative importance of test parameters e.g., contact time, particle size,
pH and U(+6) aqueous speciation was determined. The results show that sorption on montmorillonite is a funtion of pH depending
strongly on the aqueous U(+6) species. It reaches a maximum at near neutral pH(pH}7). At low and at high pH solutions the
sorption values of uranium are poor. These sorption values were attributed to the formation of aqueous U(+6) carbonate complexes
in alkaline conditions and the ionexchange process between UO2
+2 species and interlayer cations on montmorillonite in acidic solutions. 相似文献