Efficient dual adsorption of eosinY and methylene blue from aqueous solution using nanocomposite of graphene oxide nanosheets and ZnO nanospheres

Nisar Ahmad,Samina Kar,Dilshad Hussain,목영선,가야스 우딘 시디퀴 한국화학공학회 2022 Korean Journal of Chemical Engineering Vol.39 No.11

A versatile graphene oxide nanosheets-ZnO nanospheres nanocomposite was synthesized for removal of dyes via adsorption process and characterized by various techniques, such as X-ray diffraction (XRD), Scanning electron microscopy (SEM), Fourier transform infrared (FTIR), and zeta potential (ZP) analyzer. The synthesized nanocomposite (NCs) was utilized as an efficient adsorbent for the removal of anionic dye eosin y (EY) as well as cationic dye methylene blue (MB) from aqueous solutions. The kinetics of adsorption was studied by pseudo-first and pseudosecond- order kinetics and the adsorption data was well in agreement with the pseudo-second-order model. The R2 values of 0.9971 and 0.9839 of the second order for EY and MB, respectively, were greater than that of the first order. To calculate the most suitable isotherm model for adsorption, the Freundlich and Langmuir isotherms were applied and the data for both dyes fitted well with the Langmuir model. The maximum adsorption capacities obtained from Langmuir isotherm for EY and MB were 555.55 and 250mg/g, respectively. Remarkably, 3.0mg/13mL of nanocomposite adsorbed 0.1mg/mL of EY and 0.04mg/mL of MB in the very short time of 10 and 15minutes, respectively. The high adsorption efficiency of GO/ZnO NCs suggests that they may be a useful adsorbent for the purification of industrial wastewater.

Association of a VDR Gene Polymorphism with Risk of Colorectal Cancer in Kashmir

Rasool, Sabha,Kadla, Showkat Ahmad,Khan, Tanzeela,Qazi, Falak,Shah, Nisar Ahmad,Basu, Javed,Khan, Bilal Ahmad,Ahktar, Qulsum,Sameer, Aga Syed,Ganai, Bashir Ahmad Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.10

Roles of the vitamin D receptor in etiology of cancers, including colorectal cancer, have been repeatedly stressed in different parts of the world. A case control study aimed to evaluate the relationship between the two was therefore initiated in Kashmir, known both for its increasing incidence of gastrointestinal cancers and deficiency of micro-nutrients especially vitamin D. The study included a total of 617 subjects (312 colorectal cancer cases and 305 controls), with sampling carried out over a period of 5 years. DNA samples from the blood of the subjects were analyzed for start codon Fok I VDR polymorphism. We obtained a 1.3 fold increased risk among individuals homozygous for f variants as compared to subjects homozygous for F allele (odds ratio OR 1.3, 95%CI, 0.861-1.65). Our study also showed statistically significant results when dwelling and tumor location characteristics were stratified with Fok I polymorphism, all of which suggests a possible role of Fok I polymorphism in the etiology of CRC in Kashmir.

Synthesis and characterization of PANI/MOF-199/Ag nanocomposite and its potential application as non-enzymatic electrochemical sensing of dopamine

Nisar Asia,Khan Muzamil Ahmad,Hussain Zakir 한국세라믹학회 2022 한국세라믹학회지 Vol.59 No.3

In this research study, a highly selective and sensitive electrochemical sensor was designed by coating the glassy carbon electrode (GCE) with the novel PANI/MOF-199/Ag nanocomposite for the non-enzymatic electrochemical detection of dopamine (DA). PANI/MOF-199/Ag nanocomposite was prepared by the in situ chemical oxidative polymerization of aniline monomer in the presence of MOF-199 followed by the deposition of Ag nanoparticles using an in situ chemical reduction route. Characterization techniques such as Scanning electron microscopy (SEM), X-ray powder diffraction (XRD), Fourier transform infra-red spectroscopy (FTIR), and Raman analysis were used to find out the successful synthesis of the prepared samples. Meanwhile, the electrochemical performance was investigated by chronoamperometry (CA) and cyclic voltammetry (CV) not only at different molar concentrations of DA but also with various compositions of Ag nanoparticles loaded. The PANI/MOF-199/Ag-3% modified electrode exhibited good electro-catalytic activity with high sensitivity of 1.421 μA μM−1 cm− 2 and a low detection limit (LOD) of 0.22 μM (S/N = 3) towards DA. Moreover, in the presence of common interfering biological compounds such as glucose (Glu), uric acid (UA), and ascorbic acid (AA), the fabricated electrochemical sensor was found selective to DA detection.

A novel kind of Hermite based Frobenius type Eulerian polynomials

Waseem Ahmad Khan,Kottakkaran Sooppy Nisar,MEHMET ACIKGOZ,UGUR DURAN 장전수학회 2019 Proceedings of the Jangjeon mathematical society Vol.22 No.4

After the inspirational innovation of fuzzy set by Zadeh in 1965, Kramosil and Michalek in 1975 pioneered the concept of fuzziness in metric spaces and very rst they formulated the notion of fuzzy met- ric spaces. Jungck introduced the idea of commutativity (in 1976) and compatibility (1986) in metric spaces and same are utilized by Subrah- manyam (in 1995) in fuzzy metric spaces to prove an analogues version of Jungck result. In this paper, we prove common xed point theorems for a pair of self-maps by introducing a new contraction which neither requires completeness of spaces nor continuity and compatible property of maps. An open problem and an example is given to justify the im- portance of our main result.

Wage Convergence across European Regions : Do International Borders Matter?

( Amber Naz ),( Nisar Ahmad ),( Amjad Naveed ) 세종대학교 경제통합연구소 2017 Journal of Economic Integration Vol.32 No.1

This study focuses on wage convergence among the member states of the European Union by addressing three important questions. First, is there average wage convergence in European Union regions? Second, if there is wage convergence, are regional wage levels converging to a single, steady state level (unconditional convergence) or to their own steady state level (conditional convergence)? Third, do international borders matter for average wage convergence? By using a panel data set covering 203 Nomenclature of Territorial Units for Statistics-2 level regions from 1996 to 2006, the present study finds wage convergence for internal regions (regions within the same country) but no evidence of convergence for border regions (neighboring regions across international borders). These results imply that wage convergence is somehow restricted by international borders. These results are robust with both parametric and non-parametric approaches of testing convergence.

High rate capability and long cycle stability of Cr₂O₃ anode with CNTs for lithium ion batteries

Abbas, Syed Mustansar,Ahmad, Nisar,Ata-ur-Rehman, Nisar,Rana, Usman Ali,Khan, Salah Ud-Din,Hussain, Shabbir,Nam, Kyung-Wan Elsevier 2016 ELECTROCHIMICA ACTA Vol.212 No.-

<P><B>Abstract</B></P> <P>The present study describes the synthesis of nanocomposite materials based on chromium oxide (Cr<SUB>2</SUB>O<SUB>3</SUB>) nanoparticles and carbon nanotubes (CNTs) (Cr<SUB>2</SUB>O<SUB>3</SUB>–CNT<SUB>(x%)</SUB>) by <I>in-situ</I> chemical co-precipitation method. The physical studies of these materials using a wide range of analytical techniques reveal high surface area and narrow pore size distribution of these nanocomposite materials, indicating homogenous dispersion of Cr<SUB>2</SUB>O<SUB>3</SUB> nanoparticles (particle sizes ∼20-30nm) on the surface of CNTs. The first cycle discharge capacity of 1120 <SUP> mAhg -1 </SUP> for electrodes fabricated from Cr<SUB>2</SUB>O<SUB>3</SUB> alone, which is improved for Cr<SUB>2</SUB>O<SUB>3</SUB>–CNT<SUB>(0.08%)</SUB> nanocomposite (1199 <SUP> mAhg -1 </SUP> ). This nanocomposite material achieved an overall reversible capacity of 995.3 <SUP> mAhg -1 </SUP> after 200 cycles, which can be attributed to the high surface area and the large mesoporous volume of Cr<SUB>2</SUB>O<SUB>3</SUB> nanoparticles interconnected with highly conducting network of CNTs. At higher current densities, the Cr<SUB>2</SUB>O<SUB>3</SUB>–CNT<SUB>(x%)</SUB> nanocomposite electrodes exhibited high lithium storage capacity compared to the electrode fabricated from Cr<SUB>2</SUB>O<SUB>3</SUB> nanoparticles alone. Overall, the Cr<SUB>2</SUB>O<SUB>3</SUB>–CNT<SUB>(0.08%)</SUB> nanocomposite electrode displayed high stability under varying current rates with overall high capacity retention and highest reversible capacity of 719 <SUP> mAhg -1 </SUP> at a current rate of 2000 <SUP> mAhg -1 </SUP> . This highly enhanced rate capability and excellent cycling stability of Cr<SUB>2</SUB>O<SUB>3</SUB>–CNT<SUB>(0.08%)</SUB> nanocomposite electrode can be ascribed to the synergistic effect of CNTs (anchored with the Cr<SUB>2</SUB>O<SUB>3</SUB> nanoparticles). The outcome of this study offers a possibility of improving lithium ion storage of Cr<SUB>2</SUB>O<SUB>3</SUB> nanoparticles by carefully controlling their size and shape along with the use of a suitable buffering matrix like CNTs.</P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Annihilating Conditions of Generalized Skew Derivations on Lie Ideals

Nadeem Ur Rehman,Sajad Ahmad Pary,Junaid Nisar 경북대학교 자연과학대학 수학과 2023 Kyungpook mathematical journal Vol.63 No.3

Let A be a prime ring of char(A)̸= 2, L a non-central Lie ideal of A, F a generalized skew derivation of A and p ∈ A, a nonzero fixed element. If pF(η)η ∈ C for any η ∈ L , then A satisfies S4.

Antimicrobial Evaluation and Characterization of Copper Nanoparticles Synthesized by the Simple Chemical Method

Arshad Hussain Wazir,Qudratullah Khan,Nisar Ahmad,Faizan Ullah,Imdadullah Quereshi,Hazrat Ali 한국재료학회 2022 한국재료학회지 Vol.32 No.2

Copper nanoparticles (CuNPs) are considered of great importance due to their high catalytic and antimicrobial activities. This study focuses on the preparation and characterization of CuNPs, and on their antibacterial/antifungal activities. A copper salt (copper sulfate pentahydrate) as precursor, starch as stabilizing agent, and ascorbic acid as reducing agent were used to fabricate CuNPs. The resulting product was characterized via different techniques such as X-ray diffractrometry (XRD), Fourier Transform Infrared (FTIR) spectroscopy, and Scanning electron microscopy (SEM) to confirm its characteristic properties. Employing the Scherrer formula, the mean crystallite sizes of copper (Cu) and cuprous oxide (Cu2O) nanocrystals were found to be 29.21 and 25.33 nm, respectively, as measured from the main X-ray diffraction peaks. The functional groups present in the resulting CuNPs were confirmed by FTIR. In addition, the engineered CuNPs showed antibacterial and antifungal activity against tested pathogenic bacterial and fungal strains.

ON SOME FORMULAS FOR THE GENERALIZED APPELL TYPE FUNCTIONS

Agarwal, Praveen,Jain, Shilpi,Khan, Mumtaz Ahmad,Nisar, Kottakkaran Sooppy Korean Mathematical Society 2017 대한수학회논문집 Vol.32 No.4

A remarkably large number of special functions (such as the Gamma and Beta functions, the Gauss hypergeometric function, and so on) have been investigated by many authors. Motivated the works of both works of both Burchnall and Chaundy and Chaundy and very recently, Brychkov and Saad gave interesting generalizations of Appell type functions. In the present sequel to the aforementioned investigations and some of the earlier works listed in the reference, we present some new differential formulas for the generalized Appell's type functions ${\kappa}_i$, $i=1,2,{\ldots},18$ by considering the product of two $_4F_3$ functions.

A Novel Compact Ultra-Wideband Frequency-Selective Surface-Based Antenna for Gain Enhancement Applications

Din Iftikhar Ud,Ullah Waheed,Abbasi Nisar Ahmad,Ullah Sadiq,Shihzad Waleed,Khan Bilawal,Jayakody Dushantha Nalin K. 한국전자파학회 2023 Journal of Electromagnetic Engineering and Science Vol.23 No.2

This article presents a compact ultra-wideband (UWB) circular monopole antenna with a frequency-selective surface (FSS) for gain enhancement. The proposed antenna has a circular patch with circular cuts at the edges and is excited by a microstrip feed. The bottom plane is truncated and further modified by two triangular cuts at the sides and one rectangular cut in the middle to improve the radiation characteristics of the UWB antenna. The antenna is designed on an FR-4 substrate with a thickness of 1.6 mm, a relative permittivity of 4.3, and planner dimensions of 30 mm × 30 mm. To improve the proposed antenna’s gain, an FSS is designed that consists of periodic unit cells of metal printed on the upper layer of an FR-4 substrate with dimensions of 0.11λ × 0.11λ at the lowest operating frequency of 3.3 GHz. The FSS shows a very low transmission coefficient and linearly reducing reflection phase with increasing frequency over a frequency range of 3.3–10.8 GHz. The gain of the proposed antenna is increased from 3 dB to 8.1 dB at 9 GHz by placing the antenna on the FSS. Moreover, the prototype of the proposed antenna is fabricated, and the experimental results are measured, which show close agreements with simulated results. The FSS-based antenna has directional radiation patterns, making it a potential candidate for ground-penetrating radar and UWB applications.