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141.
142.
M.B. Pandey Sharad Kumar Pandey U.B. Singh R. Dhar M. Tykarska R. Dąbrowski 《Liquid crystals》2013,40(12):1879-1888
Thermodynamical, optical and dielectric characterisation of a material possessing ferroelectric SmC* and hexatic SmB* phases has been carried out. Phase identification has been done by miscibility studies. From the dielectric studies, a relaxation mechanism is observed in the low MHz region of the SmA* phase, which is related to the tilt fluctuation (soft mode) of the directors. In the SmC* phase, another collective relaxation mechanism has been observed in the kHz region, which is related to the phase fluctuation (Goldstone mode) of the directors. In the SmBh* phase, 2-weak relaxation modes are observed in the kHz and MHz frequency range, respectively, due to individual molecular rotations. 相似文献
143.
The Claisen rearrangement of allyl phenyl ethers is a fundamental reaction in organic synthesis with a variety of applications in perfumes, flavors, pharmaceuticals, agrochemicals, polymers, fine chemicals, and intermediate industries. The development of environmentally benign processes using solid acid catalysts is becoming an area of growing interest. It was accomplished in an efficient, economical, environmentally friendly manner and is 100% selective toward alllyl phenols by employing UDCaT‐5 as solid acid catalyst. 相似文献
144.
Vijayavitthal T. Mathad Gorakshanath B. Shinde Sharad S. Ippar Navnath C. Niphade Raghavendra K. Panchangam Pravinchandra J. Vankawala 《合成通讯》2013,43(3):341-346
An efficient synthesis of 1-(naphthalen-1-yl)ethanamine ( RS -2) and its practical resolution to optically pure (1R)-(naphthalen-1-yl)ethanamine ( R -(+)-2), a key intermediate in the synthesis of cinacalcet hydrochloride (1), is described. The resolution of RS -2 using R-(?)-mandelic acid as a resolving agent in ethanol was established on an industrial scale to give pure R -(+)-2 with >99.8% ee after liberation of the amine from its mandelate salt. An efficient process for the racemization of undesired isomer S -(?)-2 is also provided to maximize the yield of desired enantiomer. 相似文献
145.
K. V. Vimalnath A. Rajeswari Viju Chirayil P. L. Sharad K. C. Jagadeesan P. V. Joshi Meera Venkatesh 《Journal of Radioanalytical and Nuclear Chemistry》2011,290(1):221-225
64Cu (t1/2 12.7 h) is a versatile radionuclide owing to its unique decay scheme and exhibits three types of decay electron capture (41%),
β− (40%), β+ (19%) that is useful in nuclear medicine applications. Different batches of natural copper oxide (CuO) and 99.9% enriched
63CuO targets were irradiated in research reactors at a neutron flux of 6.6 × 1012 n cm−2 s−1 for duration of 3 days. Irradiated samples dissolved in hydrochloric acid solution were measured in HPGe-MCA system, the
activity of 64Cu, co-produced radionuclide impurities and radionuclide purity was determined. Average specific activity of 254 GBq 64Cu per g Cu and ~348 GBq 64Cu per g Cu was recorded at the end of irradiation from natural and enriched CuO targets, respectively. 相似文献
146.
Ajay Kumar Sandeep Kaur Sukhvinder Dhiman Prithvi Pal Singh Gaurav Bhatia Sharad Thakur Hardeep Singh Tuli Upendra Sharma Subodh Kumar Abdulmajeed G. Almutary Abdullah M. Alnuqaydan Arif Hussain Shafiul Haque Kuldeep Dhama Satwinderjeet Kaur 《Molecules (Basel, Switzerland)》2022,27(11)
Onosma bracteata Wall. is an important medicinal and immunity-enhancing herbs. This plant is commonly used in the preparation of traditional Ayurvedic drugs to treat numerous diseases. Inspired by the medicinal properties of this plant, the present study aimed to investigate the antiproliferative potential and the primary molecular mechanisms of the apoptotic induction against human osteosarcoma (MG-63) cells. Among all the fractions isolated from O. bracteata, ethyl acetate fraction (Obea) showed good antioxidant activity in superoxide radical scavenging assay and lipid peroxidation assay with an EC50 value of 95.12 and 80.67 µg/mL, respectively. Silica gel column chromatography of ethyl acetate (Obea) fraction of O. bracteata yielded a pure compound, which was characterized by NMR, FTIR, and HR-MS analysis and was identified as 1,2-benzene dicarboxylic acid, bis (2-methyl propyl) ester (BDCe fraction). BDCe fraction was evaluated for the antiproliferative potential against human osteosarcoma MG-63, human neuroblastoma IMR-32, and human lung carcinoma A549 cell lines by MTT assay and exhibited GI50 values of 37.53 μM, 56.05 μM, and 47.12 μM, respectively. In MG-63 cells, the BDCe fraction increased the level of ROS and simultaneously decreased the mitochondria membrane potential (MMP) potential by arresting cells at the G0/G1 phase, suggesting the initiation of apoptosis. Western blotting analysis revealed the upregulation of p53, caspase3, and caspase9 while the expressions of p-NF-κB, p-Akt and Bcl-xl were decreased. RT-qPCR studies also showed upregulation in the expression of p53 and caspase3 and downregulation in the expression of CDK2, Bcl-2 and Cyclin E genes. Molecular docking analysis displayed the interaction between BDCe fraction with p53 (−151.13 kcal/mol) and CDK1 (−133.96 kcal/mol). The results of the present work suggest that the BDCe fraction has chemopreventive properties against osteosarcoma (MG-63) cells through the induction of cell cycle arrest and apoptosis via Akt/NF-κB/p53 pathways. This study contributes to the understanding of the utilization of BDCe fraction in osteosarcoma treatment. 相似文献
147.
Rory C. McNulty Keir Penston Sharad S. Amin Sandro Stal Jie Yie Lee Mario Samperi Lluïsa Pérez-García Jamie M. Cameron Lee R. Johnson David B. Amabilino Graham N. Newton 《Angewandte Chemie (International ed. in English)》2023,62(12):e202216066
The mixing of [V10O28]6− decavanadate anions with a dicationic gemini surfactant ( gem ) leads to the spontaneous self-assembly of surfactant-templated nanostructured arrays of decavanadate clusters. Calcination of the material under air yields highly crystalline, sponge-like V2O5 ( gem -V2O5 ). In contrast, calcination of the amorphous tetrabutylammonium decavanadate allows isolation of a more agglomerated V2O5 consisting of very small crystallites ( TBA -V2O5 ). Electrochemical analysis of the materials’ performance as lithium-ion intercalation electrodes highlights the role of morphology in cathode performance. The large crystallites and long-range microstructure of the gem -V2O5 cathode deliver higher initial capacity and superior capacity retention than TBA -V2O5 . The smaller crystallite size and higher surface area of TBA -V2O5 allow faster lithium insertion and superior rate performance to gem -V2O5 . 相似文献
148.
Anil Disale Chittaranjan Nayak Nagesh Suryawanshi Nitin Jadhav Umesh Jagdale Gunwant Kate Sunil Thakare Shri Prakash Pandey Prakhakar Sharma Amit Saxena 《Macromolecular Symposia》2024,413(1):2300009
Industrial waste locks are used as raw materials to reduce harmful effects on the environment and improve environmental performance. Marble clay powder can be used as a filling aid and can fill voids in concrete structures. This article will show you how to use a maximum natural sand alternative in concrete with marble powder and quarry dust. The challenge of the 21st century is to change to a new form that can support the natural system. This necessitates a radical rethinking of how to give the community infrastructure and housing. Making a concerted effort to develop novel, innovative, and alternative construction materials may be necessary. Jungles of concrete around cause's impact on the Environment and it would result in climate change. Mankind must avoid the use of things that are detrimental to the environment. So in this paper, it is decided to address the issue by adopting the use of the green concrete concept which is environmentally friendly. Green concrete is concrete made up using industrial wastes such as marble powder, quarry dust, wood ash, paper pulp, etc. Green concrete, which is capable of sustainable development, helps to reduce the consumption of natural resources, energy use, and environmental pollution. Green concrete is more cost-effective than ordinary concrete and reduces the cost of resultant concrete by 14%–20%. It is also observed that the alkali-aggregate reaction and sulfate attack resistance of concrete are both significantly improved. Green concrete is a useful tool for lowering environmental pollution and enhancing concrete's resistance to harsh conditions. All stages of infrastructure construction and rehabilitation will follow this trend of using new cement and techniques. Green concrete's adaptability and its performance derivatives will meet a variety of future needs. 相似文献