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61.
Naveen Mulakayala IsmailKottur Mohan Kumar Rajesh Kumar RapoluBhaskar Kandagatla Pallavi RaoSrinivas Oruganti Manojit Pal 《Tetrahedron letters》2012,53(45):6004-6007
A clean process has been developed for the ipso-hydroxylation of aryl and heteroaryl boronic acids to the corresponding phenols using commercially available and recyclable Amberlite IR-120 resin and aqueous hydrogen peroxide as an oxidizing agent. The ion-exchange sulfonic acid resin catalyst could be readily recycled by filtration and directly reused at least four times without any significant loss of activity. 相似文献
62.
Nagaraja Sreeharsha Samathoti Prasanthi Satyavarapu Veera Venkata Naga Satya Mahalakshmi Prakash S. Goudanavar Nimbagal Raghavendra Naveen Buduru Gowthami Santosh Fattepur Girish Meravanige Syed Mohammed Basheeruddin Asdaq Md. Khalid Anwer Bandar Aldhubiab Mohammed Monirul Islam Mohammed Habeebuddin Mallikarjun Telsang Mazen Al Gharsan Michelyne Haroun 《Molecules (Basel, Switzerland)》2022,27(22)
A brand-new nano-crystal (NC) version of the hydrophobic drug Paclitaxel (PT) were formulated for cancer treatment. A stable NC formulation for the administration of PT was created using the triblock co-polymer Pluronic F127. To achieve maximum entrapment effectiveness and minimal particle size, the formulation was improved using the central composite design by considering agitation speed and vacuum pressure at five levels (coded as +1.414, +1, 0, −1, and −1.414). According to the Design Expert software’s predictions, 13 runs were created and evaluated for the chosen responses. The formulation prepared with an agitation speed of 1260 RPM and a vacuum pressure of 77.53 mbar can meet the requirements of the ideal formulation in order to achieve 142.56 nm of PS and 75.18% EE, according to the level of desirability (D = 0.959). Folic acid was conjugated to Pluronic F127 to create folate receptor-targeted NC. The drug release profile of the nano-crystals in vitro demonstrated sustained release over an extended period. Folate receptor (FR)-targeted NC (O-PT-NC-Folate) has also been prepared by conjugating folic acid to Pluronic F127. MTT test is used to validate the targeting efficacy on the FR-positive human oral cancer cell line (KB). At pharmacologically relevant concentrations, the PT nano-crystal formulation did not cause hemolysis. Compared to non-targeted NC of PT, the O-PT-NC-Folate showed a comparable but more sustained anti-cancer effect, according to an in vivo anti-tumor investigation in NCI/ADR-RES cell lines. The remarkable anti-tumor effectiveness, minimal toxicity, and simplicity of scale-up manufacturing of the NC formulations indicate their potential for clinical development. Other hydrophobic medications that are formulated into nano-systems for improved therapy may benefit from the formulation approach. 相似文献
63.
Prabakaran Rajendran Prasanna Naveen Kumar J. Mohan Lal Dhasan Selvam C. Harish Sivasankaran 《Journal of Thermal Analysis and Calorimetry》2020,139(2):941-952
Journal of Thermal Analysis and Calorimetry - In the present work, the melting behavior of a fatty acid-based phase change material (PCM) with the addition of functionalized graphene nanoplatelets... 相似文献
64.
The authors compare the subband compression capabilities of eight filter sets (consisting of linear-phase quadrature mirror filters (QMFs), perfect reconstruction filters, and nonlinear phase wavelets) at different bit rates, using-a filter-based bit allocation procedure. Using DPCM and PCM in HDTV subband coding, it is found that QMFs have an edge over the rest. 相似文献
65.
Naveen Jaglan Samir Dev Gupta Shweta Srivastava 《International Journal of Electronics》2018,105(1):58-72
Ultra-wideband (UWB) disc monopole antenna with crescent shaped slot for double band-notched features is presented. Planned antenna discards worldwide interoperability for microwave access (WiMAX) band (3.3–3.6 GHz) and wireless local area network (WLAN) band (5–6 GHz). Defected ground compact electromagnetic band gap (DG-CEBG) designs are used to accomplish band notches in WiMAX and WLAN bands. Defected ground planes are utilised to achieve compactness in electromagnetic band gap (EBG) structures. The proposed WiMAX and WLAN DG-CEBG designs show a compactness of around 46% and 50%, respectively, over mushroom EBG structures. Parametric analyses of DG-CEBG design factors are carried out to control the notched frequencies. Stepwise notch transition from upper to lower frequencies is presented with incremental inductance augmentation. The proposed antenna is made-up on low-cost FR-4 substrate of complete extents as (42 × 50 × 1.6) mm3.Fabricated sample antenna shows excellent consistency in simulated and measured outcomes. 相似文献
66.
Naveen Kumar 《Tetrahedron letters》2004,45(35):6611-6613
An efficient synthesis and structural aspects of a novel class of selenium bearing hexa-hosts by the reaction of hexafluorobenzene or hexakis(bromomethyl) benzene with RSe− ions is demonstrated. However, under identical reaction conditions, our attempts to prepare tellurium analogues by the reaction of RTe− (R = Ph or p-CH3C6H4-) with hexafluorobenzene or hexakis(bromomethyl)benzene to obtain (RTe)6C6 and (RTeCH2)6C6 proved to be difficult. 相似文献
67.
P. Vijay Kumar Reddy P. Naveen Kumar G. V. P. Chandramouli 《Journal of heterocyclic chemistry》2005,42(2):283-286
A variety of novel 6,6′‐arylidene‐bis‐[5‐hydroxy‐9‐methyl‐2,3‐diaryl‐thieno[3,2‐g]thiocoumarins] 3a‐d , 4a‐d , 5a‐d , and 6a‐d were obtained by a reaction between 5‐hydroxy‐9‐methyl‐2,3‐diarylthieno[3,2‐g]thiocoumarins 1a‐d with aromatic aldehydes 2a‐d in isopropyl alcohol. The synthesized compounds were tested for their antimicrobial activity. 相似文献
68.
Kumar Rangaraju Satish Kim Hyorim Mergu Naveen Son Young-A 《Research on Chemical Intermediates》2020,46(1):313-328
Research on Chemical Intermediates - We synthesized a novel dihydroxotin(IV) porphyrin complex with full structural confirmation. The tin complex further converted to TiO2 composite... 相似文献
69.
An impact ionization MOSFET (IMOS) is evolved for overcoming the constraint of less than 60 mV/decade sub-threshold slope (SS) of conventional MOSFET at room temperature.In this work,first,the device performance of the p-type double gate impact ionization MOSFET (DG-IMOS) is optimized by adjusting the device design parameters.The adjusted parameters are ratio of gate and intrinsic length,gate dielectric thickness and gate work function.Secondly,the DMG (dual material gate) DG-IMOS is proposed and investigated.This DMG DG-IMOS is further optimized to obtain the best possible performance parameters.Simulation results reveal that DMG DG-IMOS when compared to DG-IMOS,shows better ION,ION/IOFF ratio,and RF parameters.Results show that by properly tuning the lengths of two materials at a ratio of 1.5 in DMG DG-IMOS,optimized performance is achieved including ION/IoFF ratio of 2.87 × 109 A/μm with ION as 11.87 × 10-4 A/μm and transconductance of 1.06 × 10-3 S/μm.It is analyzed that length of drain side material should be greater than the length of source side material to attain the higher transconductance in DMG DG-IMOS. 相似文献
70.
S. Naveen R. S. Policegoudra S. M. Aradhya L. J. Rao K. Farhath 《Chemistry of Natural Compounds》2012,48(2):225-230
The ethanol extract of Decalepis hamiltonii roots was subjected to antioxidant activity-guided fractionation by repeated silica gel column chromatography to get a pure
antioxidant compound which was subjected to extensive analysis by UV, IR, LC-MS, and 2D HMQC NMR. The spectral data of the
isolated compound was analyzed, and its structure was elucidated as decalpoline, a novel antioxidant compound not reported
so far. Decalpoline exhibited multiple antioxidant properties like DPPH scavenging activity, superoxide radical scavenging
activity, lipid peroxidation inhibitory activity, metal chelating and total reducing activity. 相似文献