Variation in Precipitation, Surface Water Flow and the Intensity of Groundwater Loss in 14 Districts of Kabul City

Ghulam Abbas Leaqat,Jeffrey Scott Owen 한국대기환경학회 2019 한국대기환경학회 학술대회논문집 Vol.2019 No.11

Magnetic and optical properties of Gd-Tl substituted M-type barium hexaferrites synthesized by co-precipitation technique

Ghulam Abbas Ashraf,Lanting Zhang,Waseem Abbas,Ghulam Murtaza 한국물리학회 2019 Current Applied Physics Vol.19 No.4

The substitution of numerous cations into hexagonal ferrite has been extensively used to endow novel properties and functionalities for various applications. In the present work Gd-Tl substituted barium hexaferrites prepared by co-precipitation process, having the composition Ba0.75Cu0.25(GdxTl0.5-x)Fe11.5O19 (x=0.0, 0.25 and 0.50). The hexaferrite formation during calcination of sample x=0.25 was confirmed by TGA/DSC which was processed at 1000 °C for 3 h. The analysis of X-ray diffraction depicts the existence of magneto-plumbite structure with the formation of a minor secondary α–Fe2O3 phase x≤0.0 and BaFe2O4 phase x≤0.50. UV–Vis spectra reveal the dropping down behavior in the optical energy band gap from 2.47 eV to 1.74 eV. The grains with hexagonal platelet-like shape having size of 0.415–0.446 μm of magnetic powder nanoparticles (MPs) are observed by SEM images. The energy dispersive spectrometer (EDS) analysis was employed for presence of ferrite elements within a single particle. Hysteresis loops signifies the magnetization (Ms) and remnant magnetization (Mr) first increases up to x=0.25 then reduces with the substitution (x) increment; contrarily, the coercivity (Hc) exhibited initially decreased with maximum content of Tl at x=0.0 then increases at x=0.25 after that it decreases at x=0.50. Maximum values such as Ms (51.727 emu/g), Mr (28.061 emu/g), and Hc (4.057 kOe) are attained for x=0.25 at room temperature. The synthesized magnetic nanoparticles are found to be suitable for microwave absorbing materials, permanent magnets, catalyst, high density recording media and optoelectronic devices.

Aloe vera gel enriched with garlic essential oil eff ectively controls anthracnose disease and maintains postharvest quality of banana

Ghulam Khaliq,Hafi z Tassawar Abbas,Intazar Ali,Muhammad Waseem 한국원예학회 2019 Horticulture, Environment, and Biotechnology Vol.60 No.5

Banana is a tropical fruit that suff ers from several postharvest diseases during transportation and storage. Anthracnosecaused by the fungus Colletotrichum musae is the most destructive postharvest disease of banana. The aim of this studywas to determine the antifungal activities of Aloe vera (AV) gel coating alone or in combination with garlic oil (GO) at twoconcentrations (AV + GO 0.05% and AV + GO 0.1%) in vitro and in vivo against anthracnose disease of banana fruit. Theresults showed that the AV gel coating incorporated with GO was more eff ective as a fungicide than AV gel alone. The highestantifungal activity was observed in AV + GO 0.1% treatment, which signifi cantly inhibited the mycelial growth and sporegermination by 87.7 and 91.2%, respectively, compared to the control. In vivo study indicated that AV gel combined withGO 0.1% eff ectively reduced anthracnose disease incidence (92.5%) and severity (81.0%) in artifi cially inoculated bananafruit after 15 days of storage. The same treatment delayed the changes in weight loss, fi rmness, soluble solids concentration,and titratable acidity. Moreover, AV gel coating and GO enhanced total phenolic contents and total antioxidant activities ofbanana fruit. These results suggested that AV gel combined with GO can be used as an eff ective biofungicide for controllinganthracnose disease of banana fruit.

Temperature-Dependent and Gate-Tunable Rectification in a Black Phosphorus/WS₂ van der Waals Heterojunction Diode

Dastgeer, Ghulam,Khan, Muhammad Farooq,Nazir, Ghazanfar,Afzal, Amir Muhammad,Aftab, Sikandar,Naqvi, Bilal Abbas,Cha, Janghwan,Min, Kyung-Ah,Jamil, Yasir,Jung, Jongwan,Hong, Suklyun,Eom, Jonghwa American Chemical Society 2018 ACS APPLIED MATERIALS & INTERFACES Vol.10 No.15

<P>Heterostructures comprising two-dimensional (2D) semiconductors fabricated by individual stacking exhibit interesting characteristics owing to their 2D nature and atomically sharp interface. As an emerging 2D material, black phosphorus (BP) nanosheets have drawn much attention because of their small band gap semiconductor characteristics along with high mobility. Stacking structures composed of p-type BP and n-type transition metal dichalcogenides can produce an atomically sharp interface with van der Waals interaction which leads to p-n diode functionality. In this study, for the first time, we fabricated a heterojunction p-n diode composed of BP and WS<SUB>2</SUB>. The rectification effects are examined for monolayer, bilayer, trilayer, and multilayer WS<SUB>2</SUB> flakes in our BP/WS<SUB>2</SUB> van der Waals heterojunction diodes and also verified by density function theory calculations. We report superior functionalities as compared to other van der Waals heterojunction, such as efficient gate-dependent static rectification of 2.6 × 10<SUP>4</SUP>, temperature dependence, thickness dependence of rectification, and ideality factor of the device. The temperature dependence of Zener breakdown voltage and avalanche breakdown voltage were analyzed in the same device. Additionally, superior optoelectronic characteristics such as photoresponsivity of 500 mA/W and external quantum efficiency of 103% are achieved in the BP/WS<SUB>2</SUB> van der Waals p-n diode, which is unprecedented for BP/transition metal dichalcogenides heterostructures. The BP/WS<SUB>2</SUB> van der Waals p-n diodes have a profound potential to fabricate rectifiers, solar cells, and photovoltaic diodes in 2D semiconductor electronics and optoelectronics.</P> [FIG OMISSION]</BR>

Whole exome sequencing revealed novel variants in consanguineous Pakistani families with intellectual disability

Iqra Ghulam Rasool,Muhammad Yasir Zahoor,Muhammad Iqbal,Aftab Ahmad Anjum,Fatima Ashraf,Hafiz Qamar Abbas,Hafiz Muhammad Azhar Baig,Tariq Mahmood,Wasim Shehzad 한국유전학회 2021 Genes & Genomics Vol.43 No.5

Background Intellectual disability (ID) is a heterogeneous disorder afecting 1–3% of the population. Elucidation of monogenic variants for ID is a current challenge. These variants can be better demonstrated in consanguineous afected families. Objective The study was designed to fnd the genetic variants of ID in consanguineous families. Methods We analyzed fve unrelated consanguineous Pakistani families afected with ID using whole exome sequencing (WES). Data was analyzed using diferent bioinformatics tools and software. Results We mapped four variants including three novels in four diferent ID known genes. Each variant is found in a different family, co-segregating with a recessive pattern of inheritance. The novel variants found are; c. 2_4del (p.?) mapped in ROS1 and c. 718G>A (p.Gly240Arg) in GRM1. Another novel causative variant, c.2673del (p.Gly892Aspfs*17) identifed in COL18A1 in a recessive form, a gene reported for Knobloch syndrome that manifests ID along with typical retinal abnormalities, and this phenotype was confrmed on reverse phenotyping. A mutation c.2134C>T (p.Arg712*) in TRAPPC9 has been found frst time in the homozygous recessive form in our enrolled three afected siblings while it was previously reported in compound heterozygous form in a Caucasian descent. While ffth family remained unsolved. Conclusion These mutations in four diferent genes with a recessive inheritance would be a contribution to the disease variant database of this devastating disorder.

Elucidating the performance-limiting electrode for all-vanadium redox flow batteries through in-depth physical and electrochemical analyses

Sheeraz Mehboob,Ghulam Ali,Saleem Abbas,정경윤,하흥용 한국공업화학회 2019 Journal of Industrial and Engineering Chemistry Vol.80 No.-

For the development of all-vanadium redoxflow batteries (VRFB) with high power ratings, it is verycrucial to identify the reasons that limit the kinetics of vanadium couples at the electrodes. This work,using two different electrode materials (a polyacrylonitrile-based carbon felt and a rayon-based graphitefelt), elucidates the redox reactions at the anode as performance-limiting ones through varioussophisticated physical and electrochemical analyses as well as the VRFB testings with/withouthomogeneous catalyst in the electrolytes and different electrode combinations. The electrode materialwith the properties of higher hydrophilicity arising from abundant surface oxygen functionalities andelectrical conductivity exhibit higher VRFB performance, particularly due to improved reaction kineticsat the anode. Moreover, the incorporation of catalyst, especially for the V3+/V2+ couple, results in asignificant improvement of VRFB performance by accelerating the kinetics of V3+/V2+ redox reactions aswell as mitigating the harmful effects of hydrogen evolution reactions and temperature-related effects.

Acacia Species for the Rehabilitation and Utilization of Salt-affected Lands and Waters

Muhammad Saqib,Ghulam Abbas,Javaid Akhtar,Muhammad Kashif Ali 한국토양비료학회 2014 한국토양비료학회 학술발표회 초록집 Vol.2014 No.6

SIMPSON'S AND NEWTON'S TYPE QUANTUM INTEGRAL INEQUALITIES FOR PREINVEX FUNCTIONS

Ali, Muhammad Aamir,Abbas, Mujahid,Sehar, Mubarra,Murtaza, Ghulam The Kangwon-Kyungki Mathematical Society 2021 한국수학논문집 Vol.29 No.1

In this research, we offer two new quantum integral equalities for recently defined qε2-integral and derivative, the derived equalities then used to prove quantum integral inequalities of Simpson's and Newton's type for preinvex functions. We also considered the special cases of established results and offer several new and existing results inside the literature of Simpson's and Newton's type inequalities.

Intercalation of cobaltocene into WS₂ nanosheets for enhanced catalytic hydrogen evolution reaction

Kwak, In Hye,Abbas, Hafiz Ghulam,Kwon, Ik Seon,Park, Yun Chang,Seo, Jaemin,Cho, Min Kyung,Ahn, Jae-Pyoung,Seo, Hee Won,Park, Jeunghee,Kang, Hong Seok The Royal Society of Chemistry 2019 Journal of Materials Chemistry A Vol.7 No.14

<P>We synthesized cobaltocene (7-20%)-intercalated WS2 nanosheets using a solvothermal process. The intercalation of cobaltocene between the expanded 1T′ phase WS2 layers was confirmed by scanning transmission electron microscopy and electron energy loss spectroscopy. The intercalated complexes exhibited excellent performance for the catalytic hydrogen evolution reaction, with a Tafel slope of 40 mV dec<SUP>−1</SUP> and a current density of 10 mA cm<SUP>−2</SUP> at 0.17 V (<I>vs.</I> RHE). Spin-polarized density functional theory calculations showed that cobaltocene is intercalated with a fivefold symmetry parallel to the WS2 plane, driven by substantial charge transfer. Reaction pathway calculations suggest that the basal S atoms just above the Co atom are the active sites, and the activation barrier of the Heyrovsky reaction determines the catalytic activity.</P>

Enhancing the performance of all-vanadium redox flow batteries by decorating carbon felt electrodes with SnO₂ nanoparticles

Mehboob, Sheeraz,Ali, Ghulam,Shin, Hyun-Jin,Hwang, Jinyeon,Abbas, Saleem,Chung, Kyung Yoon,Ha, Heung Yong Elsevier 2018 APPLIED ENERGY Vol.229 No.-

<P><B>Abstract</B></P> <P>An all-vanadium redox flow battery (VRFB) is an attractive candidate as an electrochemical energy storage system that uses conversion technology for applications that range from those requiring only a few kilowatts to those that must perform on a megawatt scale. Issues to be resolved, however, include problems with increasing the rates of charge/discharge (due to an increase in overpotentials) and cycling stability (due to the irreversibility of redox reactions at the electrodes as well as crossover of the vanadium species) that have prevented a broader market penetration of VRFB systems. One of the strategies to overcome these problems may be the introduction of electrocatalysts to the electrode surface to improve the reaction kinetics of the positive and negative redox couples, thus enabling the achievement of higher levels of power density. Therefore, carbon felt electrodes decorated with SnO<SUB>2</SUB> nanoparticles were evaluated in this study. The performance of VRFBs at a high current density of 150 mA cm<SUP>−2</SUP> with SnO<SUB>2</SUB>-deposited carbon felts returned an energy efficiency of 77.3%, with a corresponding increase in discharge capacity of 23.7% over a pristine electrode. Cycling stability of the system was also improved almost 2.7-fold compared with that of a pristine electrode at 50 mA cm<SUP>−2</SUP>. The electrocatalytic activity of SnO<SUB>2</SUB> nanoparticles facilitates a reduction in the overpotentials, which enables charge/discharge reactions at faster rates, which was confirmed by cyclic voltammetry and electrochemical impedance spectroscopy. Furthermore, confirmation of the formation of clusters of SnO<SUB>2</SUB> nanocrystals as well as their chemical and physical stability after cycling (as probed by various characterization techniques including synchrotron-based X-ray absorption) supports their feasibility as a stable, efficient and cost-effective electrocatalyst for use in VRFB systems.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Carbon felt is deposited with clusters of SnO<SUB>2</SUB> nanoparticles (3–5 nm). </LI> <LI> The SnO<SUB>2</SUB>-deposited carbon felt exhibits energy efficiency of 77.3% at 150 mA cm<SUP>−2</SUP>. </LI> <LI> Impact of SnO<SUB>2</SUB> electrocatalyst on improvement of cycling stability is also focused. </LI> <LI> Stability of electrocatalyst is probed by synchrotron radiations-based techniques. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>