Theoretical and experimental investigation on structural stability, electronic and vibrational properties of polyaniline (PANI)

Rakesh K. Sonker,Rajkamal Shastri,B.C. Yadav 장전수학회 2019 Proceedings of the Jangjeon mathematical society Vol.22 No.1

Conducting polymers have been concerned the ample interest of scientific community due to its special physical and chemical properties. Among this group of materials, the Polyaniline (PANI) merits special attention due to its high thermal and chemical stability under normal conditions, simple process of polymerization low cost and well-studied electrochemical characteristics. In the present work, Density functional theory (DFT) method has been applied for geometry optimization using B3LYP/6-31G** basis set, implemented on Gaussian 09 software package. The well-known model, time-dependent DFT (TDDFT) calculations at the UB3LYP/6-31G(d) level have been performed to investigate the tunable nature, i.e., doping processes, of polyaniline (PANI). The calculated theoretical data show strong correlation with the recent experimental reports, which validates our computational protocol. The calculated properties are extrapolated to the polymer (PANI) through a second-order polynomial fit. Changes in band gap, conductivity, and resistance of (PANI_n) and (PANI_n) (where n = 1-4 and) were studied. Further we have also synthesized and characterized the Polyaniline. The deviations in the obtained results have clearly shown the promising of Polyaniline as a quantity sensitive material that may be useful for the sensing application.

Final overall survival analysis for the phase II RECORD-3 study of first-line everolimus followed by sunitinib versus first-line sunitinib followed by everolimus in metastatic RCC

Knox, J. J.,Barrios, C. H.,Kim, T. M.,Cosgriff, T.,Srimuninnimit, V.,Pittman, K.,Sabbatini, R.,Rha, S. Y.,Flaig, T. W.,Page, R. D.,Beck, J. T.,Cheung, F.,Yadav, S.,Patel, P.,Geoffrois, L.,Niolat, J.,B Oxford University Press 2017 ANNALS OF ONCOLOGY Vol.28 No.6

<P><B>Background</B></P><P>RECORD-3 compared everolimus and sunitinib as first-line therapy, and the sequence of everolimus followed by sunitinib at progression compared with the opposite (standard) sequence in patients with metastatic renal cell carcinoma (mRCC). This final overall survival (OS) analysis evaluated mature data for secondary end points.</P><P><B>Patients and methods</B></P><P>Patients received either first-line everolimus followed by second-line sunitinib at progression (<I>n = </I>238) or first-line sunitinib followed by second-line everolimus (<I>n = </I>233). Secondary end points were combined first- and second-line progression-free survival (PFS), OS, and safety. The impacts of neutrophil lymphocyte ratio (NLR) and baseline levels of soluble biomarkers on OS were explored.</P><P><B>Results</B></P><P>At final analysis, median duration of exposure was 5.6 months for everolimus and 8.3 months for sunitinib. Median combined PFS was 21.7 months [95% confidence interval (CI) 15.1–26.7] with everolimus-sunitinib and 22.2 months (95% CI 16.0–29.8) with sunitinib-everolimus [hazard ratio (HR)<SUB>EVE-SUN/SUN-EVE</SUB>, 1.2; 95% CI 0.9–1.6]. Median OS was 22.4 months (95% CI 18.6–33.3) for everolimus-sunitinib and 29.5 months (95% CI 22.8–33.1) for sunitinib-everolimus (HR<SUB>EVE-SUN/SUN-EVE</SUB>, 1.1; 95% CI 0.9–1.4). The rates of grade 3 and 4 adverse events suspected to be related to second-line therapy were 47% with everolimus and 57% with sunitinib. Higher NLR and 12 soluble biomarker levels were identified as prognostic markers for poor OS with the association being largely independent of treatment sequences.</P><P><B>Conclusions</B></P><P>Results of this final OS analysis support the sequence of sunitinib followed by everolimus at progression in patients with mRCC. The safety profiles of everolimus and sunitinib were consistent with those previously reported, and there were no unexpected safety signals.</P><P><B>Clinical Trials number</B></P><P>ClinicalTrials.gov identifier, NCT00903175</P>

An Analytical Model of the First Eigen Energy Level for MOSFETs Having Ultrathin Gate Oxides

B. PAVAN KUMAR YADAV,ALOKE K. DUTTA 대한전자공학회 2010 Journal of semiconductor technology and science Vol.10 No.3

In this paper, we present an analytical model for the first eigen energy level (E0) of the carriers in the inversion layer in present generation MOSFETs, having ultrathin gate oxides and high substrate doping concentrations. Commonly used approaches to evaluate E0 make either or both of the following two assumptions: one is that the barrier height at the oxide-semiconductor interface is infinite (with the consequence that the wave function at this interface is forced to zero), while the other is the triangular potential well approximation within the semiconductor (resulting in a constant electric field throughout the semiconductor, equal to the surface electric field). Obviously, both these assumptions are wrong, however, in order to correctly account for these two effects, one needs to solve Schrodinger and Poisson equations simultaneously, with the approach turning numerical and computationally intensive. In this work, we have derived a closed-form analytical expression for E0, with due considerations for both the assumptions mentioned above. In order to account for the finite barrier height at the oxide-semiconductor interface, we have used the asymptotic approximations of the Airy function integrals to find the wave functions at the oxide and the semiconductor. Then, by applying the boundary condition at the oxidesemiconductor interface, we developed the model for E0. With regard to the second assumption, we proposed the inclusion of a fitting parameter in the wellknown effective electric field model. The results matched very well with those obtained from Li’s model. Another unique contribution of this work is to explicitly account for the finite oxide-semiconductor barrier height, which none of the reported works considered.

Biological and Medicinal Properties of Grapes and Their Bioactive Constituents: An Update

Yadav, Mukesh,Jain, Shalini,Bhardwaj, Aarti,Nagpal, Ravinder,Puniya, Monica,Tomar, Radha,Singh, Vinod,Parkash, Om,Prasad, G.B.K.S.,Marotta, Francesco,Yadav, Hariom The Korean Society of Food Science and Nutrition 2009 Journal of medicinal food Vol.12 No.3

The grape is one of the most valued conventional fruits, worldwide. Although most of the parts of the grapevine are useful, primarily, the grape is considered as a source of unique natural products not only for the development of valuable medicines against a number of diseases, but also for manufacturing various industrial products. Over the last few decades, apart from the chemistry of grape compounds, considerable progress has been made towards exploring the biological activities of various grape-derived constituents. Today, it is well established that in addition to serving as food, the grape is a major source of several phytochemicals. The main biologically active and well-characterized constituent from the grape is resveratrol, which is known for various medicinal properties in human diseases. This review discusses the roles of various grape-derived phytochemicals in relation to various diseases.

Characterizing the time-course of antihypertensive activity and optimal dose range of fimasartan <i>via</i> mechanism-based population modeling

Bulitta, Jü,rgen B.,Paik, Soo Heui,Chi, Yong Ha,Kim, Tae Hwan,Shin, Soyoung,Landersdorfer, Cornelia B.,Jiao, Yuanyuan,Yadav, Rajbharan,Shin, Beom Soo Elsevier 2017 European journal of pharmaceutical sciences Vol.107 No.-

<P><B>Abstract</B></P> <P>Fimasartan is a novel angiotensin II receptor blocker. Our aims were to characterize the time-course of the antihypertensive activity of fimasartan <I>via</I> a new population pharmacokinetic/pharmacodynamic model and to define its optimal dose range. We simultaneously modelled all fimasartan plasma concentrations and 24-h ambulatory blood pressure monitoring (ABPM) data from 39 patients with essential hypertension and 56 healthy volunteers. Patients received placebo, 20, 60, or 180mg fimasartan every 24h for 28days and healthy volunteers received placebo or 20 to 480mg as a single oral dose or as seven doses every 24h. External validation was performed using data on 560 patients from four phase II or III studies. One turnover model each was used to describe diastolic and systolic blood pressure. The input rates into these compartments followed a circadian rhythm and were inhibited by fimasartan. The average predicted (observed) diastolic blood pressure over 24-h in patients decreased by 10.1±7.5 (12.6±9.2; mean±SD)mmHg for 20mg, 14.2±7.0 (15.1±9.3) mmHg for 60mg, and 15.9±6.8 (11.5±9.9)mmHg for 180mg daily relative to placebo. The model explained the saturation of antihypertensive activity by counter-regulation at high fimasartan concentrations. Drug effect was maximal at approximately 23ng/mL fimasartan for diastolic and 12ng/mL for systolic blood pressure. The proposed mechanism-based population model characterized the circadian rhythm of ABPM data and the antihypertensive effect of fimasartan. After internal and external model validation, 30 to 60mg oral fimasartan given once daily was predicted as optimal dose range.</P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

An Analytical Model of the First Eigen Energy Level for MOSFETs Having Ultrathin Gate Oxides

Yadav, B. Pavan Kumar,Dutta, Aloke K. The Institute of Electronics and Information Engin 2010 Journal of semiconductor technology and science Vol.10 No.3

In this paper, we present an analytical model for the first eigen energy level ($E_0$) of the carriers in the inversion layer in present generation MOSFETs, having ultrathin gate oxides and high substrate doping concentrations. Commonly used approaches to evaluate $E_0$ make either or both of the following two assumptions: one is that the barrier height at the oxide-semiconductor interface is infinite (with the consequence that the wave function at this interface is forced to zero), while the other is the triangular potential well approximation within the semiconductor (resulting in a constant electric field throughout the semiconductor, equal to the surface electric field). Obviously, both these assumptions are wrong, however, in order to correctly account for these two effects, one needs to solve Schrodinger and Poisson equations simultaneously, with the approach turning numerical and computationally intensive. In this work, we have derived a closed-form analytical expression for $E_0$, with due considerations for both the assumptions mentioned above. In order to account for the finite barrier height at the oxide-semiconductor interface, we have used the asymptotic approximations of the Airy function integrals to find the wave functions at the oxide and the semiconductor. Then, by applying the boundary condition at the oxide-semiconductor interface, we developed the model for $E_0$. With regard to the second assumption, we proposed the inclusion of a fitting parameter in the wellknown effective electric field model. The results matched very well with those obtained from Li's model. Another unique contribution of this work is to explicitly account for the finite oxide-semiconductor barrier height, which none of the reported works considered.

Enhanced visible light photocatalytic activity of Cr³⁺-doped anatase TiO₂ nanoparticles synthesized by sol-gel method

Yadav, H. M.,Kolekar, T. V.,Barge, A. S.,Thorat, N. D.,Delekar, S. D.,Kim, B. M.,Kim, B. J.,Kim, J. S. Chapman and Hall 2016 Journal of materials science Materials in electron Vol. No.

<P>The photocatalytic degradation of methylene blue (MB) has been investigated under visible light irradiation with an incandescent light bulb using chromium doped TiO2 nanoparticles. Cr-TiO2 photocatalysts were successfully synthesized by sol-gel method at room temperature and characterized by X-ray diffraction (XRD), UV-Vis diffuse reflectance spectroscopy (UV-Vis DRS), Raman spectroscopy, Transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy. The band gap energy of the nanoparticles were estimated using UV-Vis DRS technique. With increasing Cr3+ cations content into TiO2 host lattice, the optical absorption band tuned in the visible region. XRD and TEM results reveal uniform and crystalline anatase TiO2 nanoparticles. The photodegradation of MB indicated that the photocatalytic activity of pure TiO2 nanoparticles increased with increasing Cr3+ cations concentration.</P>

Synthesis, Photophysical and Electrochemical Studies of 1,6/1,7-Diaminoperylene-3,4,9,10-tetracarboxylic Acid Bisimides:Novel NIR Fluorescent Dyes

Maruti B. Yadav,김영일,정연태 한국전기전자재료학회 2024 Transactions on Electrical and Electronic Material Vol.25 No.1

We have reported the regioisomeric mixture of novel 1,6/1,7-diaminoperylene3,4,9,10-tetracarboxylic acid bisimides by using the reaction of dibromoperylene-3,4,9,10-tetracarboxylic acid bisimides and sodium azide via copper mediate catalyst at heating condition. A one-pot single step sequential preparation of the targeted amine was designed by direct reduction of azid to amine in presence of copper sulfate and sodium ascorbate catalyst in one pot reaction condition. In addition, photochemical and electrochemical studies were also investigated. The emission wavelength shows that diamino perylene bisimide exhibits NIR region. The reported compounds were characterized by IR, NMR, and elemental analysis.

Biological and Medicinal Properties of Grapes and Their Bioactive Constituents: An Update

Mukesh Yadav,Shalini Jain,Aarti Bhardwaj,Ravinder Nagpal,Monica Puniya,Radha Tomar,Vinod Singh,Om Parkash,G.B.K.S. Prasad,Francesco Marotta,Hariom Yadav 한국식품영양과학회 2009 Journal of medicinal food Vol.12 No.3

The grape is one of the most valued conventional fruits, worldwide. Although most of the parts of the grapevine are useful, primarily, the grape is considered as a source of unique natural products not only for the development of valuable medicines against a number of diseases, but also for manufacturing various industrial products. Over the last few decades, apart from the chemistry of grape compounds, considerable progress has been made towards exploring the biological activities of various grape-derived constituents. Today, it is well established that in addition to serving as food, the grape is a major source of several phytochemicals. The main biologically active and well-characterized constituent from the grape is resveratrol, which is known for various medicinal properties in human diseases. This review discusses the roles of various grape-derived phytochemicals in relation to various diseases.

Performance Comparison of Different Variable Filters for Noise Cancellation in Real-Time Environment

B. Ananda Krishna,G. V. P. Chandra Sekhar Yadav 보안공학연구지원센터 2016 International Journal of Signal Processing, Image Vol.9 No.2

Elimination of noise from the signal is the major task in signal processing applications. Wiener filter removes noise efficiently but it requires large number of computations and it was updated with speed issue with adaptive filter. Adaptive filter has several algorithms to remove noise from the signal. This paper performs cancellation of noise from the signal using wiener filter and adaptive filter algorithms namely LMS, NLMS and RLS algorithms in real time environment. All these methods are compared using several parameters like step size, mean and variance of noise, mean square error, signal to noise ratio, speed, no. of. Iterations etc. In the existence work, the authors have compared the performance of the wiener filter & LMS algorithm in real time environment with sinusoidal input. This paper is extended by comparing different adaptive filter algorithms with the input taken in real time environment. It is observed that RLS algorithm performs noise cancellation better than all other algorithms. But it has high degree of complexity & cost while NLMS algorithm has moderate speed of performance and it is quietly chosen for several applications.