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11.
12.
Jitender Gaur Shilpa Jain Rohit Bhatia Arun Lal Narender Kumar Kaushik 《Journal of Thermal Analysis and Calorimetry》2013,112(2):1137-1143
We demonstrate synthesis of water insoluble, novel copolymer PA1 from condensation of glyoxal dihydrazone and glyoxal dihydrazone bis(dithiocarbamate) monomers having high capacity to remove metal ions from aqueous solution. The presence of a high atomic percentage of nitrogen and sulfur atoms in PA1 leads to strong ligating ability with metal ions. The monomers and the polymer have been characterized by FTIR, UV–Visible spectroscopy, CHNS elemental analysis, NMR, MALDI-MS, and TG/DTA. As a proof of concept, the PA1 is tested for its ability to remove heavy metal ions Cu2+, Co2+, Fe2+, Ni2+, Mn2+, and CrO 7 2? from aqueous solutions. PA1 efficiently removed metals ions from the metal solutions. The highest absorption ability has been observed toward the iron salts where 0.969 g metal salt is absorbed by 1 g polymer. This study has implication for inexpensive and efficient polymer for purification of water. 相似文献
13.
A. L. Ahmad B. Koohestani S. Bhatia B. S. Ooi 《Journal of Sol-Gel Science and Technology》2013,67(2):221-235
Mesoporous nanocomposite membranes with vanadium oxide–carbon nanotubes (VxOy-CNTs) embedded in γ-Al2O3 were successfully synthesized using the dip coating method. The membranes were evaluated for styrene oxidation to determine the optimum styrene conversion and benzaldehyde selectivity. Several factors that influence the preparation of defect-free coatings, such as the type of binder, the binder addition time and surface support treatments, were investigated. The physico-chemical permeation properties of the membranes were characterized using scanning electron microscope, transmission electron microscope (TEM), X-ray Diffraction XRD, Nitrogen adsorption (BET) and Thermogravimetric TGA. Response surface methodology (RSM) was used to investigate the effects of oxidant (H2O2) concentration, temperature, contact time and catalyst loading on styrene conversion and the selectivity of benzaldehyde. Based on the RSM analysis, the optimal oxidation conditions included a reaction temperature of 45 °C, a differential pressure of 1.5 bars, a molar ratio of H2O2: styrene of 1.5:1 and a catalyst loading of 30 %. These conditions resulted in the maximal styrene conversion of 25.6 and 84.9 % benzaldehyde selectivity. 相似文献
14.
Laura Sinatra Jan J. Bandolik Dr. Martin Roatsch Melf Sönnichsen Dr. Clara T. Schoeder Dr. Alexandra Hamacher Andrea Schöler Prof. Dr. Arndt Borkhardt Prof. Dr. Jens Meiler Dr. Sanil Bhatia Prof. Dr. Matthias U. Kassack Prof. Dr. Finn K. Hansen 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(50):22681-22687
15.
Sharma PK Reilly MJ Bhatia SK Sakhitab N Archambault JD Bhatia SR 《Colloids and surfaces. B, Biointerfaces》2008,64(2):229-235
Pluronic F127, a triblock copolymer of poly(ethylene oxide) (PEO) and poly(propylene oxide) (PPO), has generated considerable interest as a drug delivery vehicle due to its ability to gel at physiological temperatures. This work examines the gelation behavior of Pluronic F127 in the presence of a series of hydrophobic pharmaceuticals, to determine whether there is any correlation between gelation and physicochemical parameters of drug solutes. The study includes the local anesthetics dibucaine, lidocaine, and tetracaine; the pharmaceutical additives methyl paraben, ethyl paraben, and propyl paraben; the anti-cancer agents paclitaxel and baccatin III; and the anti-inflammatory agent sulindac. The results indicate that the presence of local anesthetics and pharmaceutical additives allows F127 solutions to form gels at lower copolymer concentrations; local anesthetics and pharmaceutical additives also shift gelation down to a lower gelation temperature. This behavior is strongly dependent on drug solubility; poorly soluble drugs (paclitaxel, baccatin III, sulindac) do not change the lower gelation temperature or minimum F127 concentration for gelation. An equation relating the decrease in gelation temperature to drug solubility is presented, and the equation fits the data well. The results have significant positive implications on the toxicity and economic issues related to use of Pluronic F127 in drug delivery. 相似文献
16.
Saurabh Bhatia Rashita Makkar Tapan Behl Aayush Sehgal Sukhbir Singh Mahesh Rachamalla Vasudevan Mani Muhammad Shahid Iqbal Simona Gabriela Bungau 《Molecules (Basel, Switzerland)》2022,27(5)
Marine drugs are abundant in number, comprise of a diverse range of structures with corresponding mechanisms of action, and hold promise for the discovery of new and better treatment approaches for the management of several chronic diseases. There are huge reserves of natural marine biological compounds, as 70 percent of the Earth is covered with oceans, indicating a diversity of chemical entities on the planet. The marine ecosystems are a rich source of bioactive products and have been explored for lead drug molecules that have proven to be novel therapeutic targets. Over the last 70 years, many structurally diverse drug products and their secondary metabolites have been isolated from marine sources. The drugs obtained from marine sources have displayed an exceptional potential in the management of a wide array of diseases, ranging from acute to chronic conditions. A beneficial role of marine drugs in human health has been recently proposed. The current review highlights various marine drugs and their compounds and role in the management of chronic diseases such as cancer, diabetes, neurodegenerative diseases, and cardiovascular disorders, which has led to the development of new drug treatment approaches. 相似文献
17.
The hydromagnetic stability of a self-gravitating composite plasma has been studied to include the effects of ion viscosity and the finiteness of the ion Larmor radius. The whole medium is embedded in a uniform horizontal magnetic field. The F. L. R. effects have been included through the stress tensor. An explicit solution for a semi-infinite plasma of finite depth and with an exponential density variation along the vertical is obtained by means of a variational principle characterizing the problem. Numerical calculations show that the influence of the effects of ion viscosity and F. L. R. is to reduce the growth rate of unstable perturbations. On the other hand the effects of neutral gas collisions have been found to be both stabilizing as well as destabilizing. 相似文献
18.
Y.N. Joshi K.S. Bhatia W.E. Jones 《Spectrochimica Acta Part B: Atomic Spectroscopy》1973,28(4):149-155
The third and fourth spectra of gallium have been photographed in the region 6000–400 Å by using a 3-m normal-incidence, vacuum spectrograph and a 3.5-m Ebert spectrograph. A three-electrode vacuum spark and a spark in helium were used as sources. New measurements for the wavelengths have confirmed earlier work and provided material to extend the analysis of Ga III and Ga IV. 相似文献
19.
Adams J Aggarwal MM Ahammed Z Amonett J Anderson BD Arkhipkin D Averichev GS Badyal SK Bai Y Balewski J Barannikova O Barnby LS Baudot J Bekele S Belaga VV Bellwied R Berger J Bezverkhny BI Bharadwaj S Bhasin A Bhati AK Bhatia VS Bichsel H Billmeier A Bland LC Blyth CO Bonner BE Botje M Boucham A Brandin AV Bravar A Bystersky M Cadman RV Cai XZ Caines H Calderón de la Barca Sánchez M Carroll J Castillo J Cebra D Chajecki Z Chaloupka P Chattopdhyay S Chen HF Chen Y Cheng J Cherney M Chikanian A 《Physical review letters》2004,93(25):252301
Results on high transverse momentum charged particle emission with respect to the reaction plane are presented for Au + Au collisions at square root s(NN)=200 GeV. Two- and four-particle correlations results are presented as well as a comparison of azimuthal correlations in Au + Au collisions to those in p + p at the same energy. The elliptic anisotropy v(2) is found to reach its maximum at p(t) approximately 3 GeV/c, then decrease slowly and remain significant up to p(t) approximately 7-10 GeV/c. Stronger suppression is found in the back-to-back high-p(t) particle correlations for particles emitted out of plane compared to those emitted in plane. The centrality dependence of v(2) at intermediate p(t) is compared to simple models based on jet quenching. 相似文献
20.
Bachhawat P Mishra S Bhatia Y Bisaria VS 《Applied biochemistry and biotechnology》2004,118(1-3):269-282
The biosynthetic activity of yeast Pichia etchellsii β-glucosidase II (BglII) expressed in recombinant Escherichia coli was utilized for synthesis of cellooligosaccharides, alkyl and terpene glucosides. Cellooligosaccharides with a degree of
polymerization of 3 and greater were resolved by thin-layer chromatography (TLC) using an ethyl acetate: 1-propanol:2-propanol:water
(8:5:1:1) solvent system followed by visualization with 0.2% naphthoresorcinol reagent. Using 2M cellobiose and 15 IU of partially purified BglII, 57 mmol/L of oligosaccharides (comprising mostly cellotriose and cellopentaose) was synthesized in 16 h. Similarly, alkyl
glucosides with chain lengths from 6 to 10 carbons were synthesized and products extracted to near purity by ethylacetate
extraction. The same extraction method was employed to separate, to near purity, various monoterpenyl (nerol, geraniol, citronellol)
glucosides. A reliable and simple method for separation of cellooligosaccharides using a combination of Bio-Gel P-2 gel filtration
and charcoal celite adsorption chromatography was developed. The cellooligosaccharides were separated to purity as confirmed
by TLC. The enzyme was among the very few that could synthesize a wide variety of glycoconjugates. 相似文献