U-Pb zircon systematics of the Mansehra Granitic Complex: implications on the early Paleozoic orogenesis in NW Himalaya of Pakistan

Mustansar Naeem,Jean-Pierre Burg,Nasir Ahmad,Muhammed Nawaz Chaudhry,Perveiz Khalid 한국지질과학협의회 2016 Geosciences Journal Vol.20 No.4

Mansehra Granitic Complex (MGC) lies in the NW Himalaya of Pakistan. The MGC magmatic rocks are peraluminous, calc-alkaline S-type granitoids. Prior to this study the Mansehra Granite had produced ages of 83 Ma by K/Ar, 215 Ma using Ar/ Ar on biotite, and 516 ± 16 Ma, using the whole rock Rb/Sr method. The Susalgali Granite Gneiss, a sheared facies of the Mansehra Granite previously regarded as older than the Mansehra Granite, was dated at 79 Ma using K/Ar on biotite. Hakale Granite, which is intrusive into the Mansehra Granite, had yielded K/Ar muscovite age of 165 Ma. The age of the leucogranites was not reported before this contribution. We have presented the revised geochronology of the MGC magmatic bodies, employing SHRIMP and LA-ICP-MS U-Pb zircon chronometry, to constraint precise crystallization ages and tectonic setting of the NW Himalaya, Pakistan. Dates of emplacement of the Mansehra Granite, leucogranites and Hakale Granite are ca. 478, 475 and 466 Ma, respectively. These new ages are comparable to U-Pb zircon and Rb/Sr dates of other granites and granite gneisses in the Lesser Himalaya to the east, in India, Nepal, south Tibet and SW China. The age components of ca. 1900–1300, 985–920, 880–800 and 690–500 Ma are interpreted as inherited grains. Geochronological and field evidence suggest that the MGC of the NW Himalaya are the product of an Andean-type Cambro-Ordovician accretional orogenesis with continental-continental settings along the northen margin of east Gondwana. On the basis of new age data of the MGC plutonic rocks it is inferred that Cambro-Ordovician accretional event commenced from SW China and extends at least up to NW Pakistan along the northern margin of east Gondwana. However, granitic rocks of Pan African affiliation prevail in central Iran and Turkey along northern and western margins of Gondwana.

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>

Social media signal detection using tweets volume, hashtag, and sentiment analysis

Nazir, Faria,Ghazanfar, Mustansar Ali,Maqsood, Muazzam,Aadil, Farhan,Rho, Seungmin,Mehmood, Irfan Springer-Verlag 2019 MULTIMEDIA TOOLS AND APPLICATIONS Vol.78 No.3

Siamese Network를 이용한 드론영상의 의미론적 변화탐지

김남혁(Namhyeok Kim),정순기(Soon Ki Jung),Mustansar Fiaz 대한공간정보학회 2022 한국지형공간정보학회 학술대회 Vol.2022 No.5

최근 토지조사 분야에서 활발히 활용되고 있는 드론영상은 항공영상에 비해 영상의 취득이 쉽고 경제적이며 저고도에서 촬영되는 만큼 영상의 해상도 또한 매우 높아 토지조사의 효율성이 매우 높다. 그러나 드론영상을 기반으로 토지를 조사하는 판독 작업은 여전히 인력에 의존하고 있어 많은 시간과 비용이 소모되고 있다. 이러한 드론영상의 판독을 자동화하기 위하여 본 논문에서는 인공지능 기술을 활용한 의미론적 변화탐지(Semantic Chage Detection)를 수행하였다. 본 논문에서 제안한 인공지능 모델을 활용하여 드론영상을 학습한 결과 계절이나 경작환경의 변화와 같은 무의미한 변화는 변화로 탐지하지 않고, 건축물의 건축이나 나대지에서 경작지로의 변화와 같은 의미있는 변화만을 높은 정확도로 탐지할 수 있었다. 의미론적 변화탐지 기술은 매우 높은 정확도로 변화지역을 추출할 수 있으므로 드론영상 기반의 토지현황조사와 같은 다양한 토지조사에 적용되어 토지조사의 효율성을 크게 향상 시킬 수 있을 것으로 기대된다.

AVO-derived attributes to differentiate reservoir facies from non-reservoirs facies and fluid discrimination in Penobscot area, Nova Scotia

Perveiz Khalid,Nisar Ahmed,Khalid Amin Khan,Mustansar Naeem 한국지질과학협의회 2015 Geosciences Journal Vol.19 No.3

The discrimination of hydrocarbon (gas or oil) facies from non-hydrocarbon (wet sands) facies is an important goal in quantitative seismic interpretation and reservoir estimation. The differentiation of hydrocarbon facies from non-hydrocarbon in Mississauga Formation of early Cretaceous in Penobscot area is a difficult task due to smaller net pay thickness and shaly sand intervals. Based on seismic interpretation and wireline logs, five sand plays are identified in the middle of Mississauga Formation. Four sands have hydrocarbons while top of sand 5 represents hydrocarbon water transition zone. Among these four, the pay sand 4 is analyzed for hydrocarbon facies. Wireline logs and seismic data are used to derive various amplitude versus offset (AVO) based attributes such as: acoustic (IP) and shear (IS) impedances, Poisson ratio (σ) etc. Further, the combined attributes e.g., product of Lamé parameters (μ, λ) with density (ρ), their ratio (λ/μ), difference between bulk modulus (K) and shear modulus (μ), Δμρ/μρ, Δ(λ/μ + 2)(λ/μ + 2) and the pore space modulus (ΚP) are also analyzed to find out the best attribute as a hydrocarbon facies discriminator from non-hydrocarbon facies in the shale imbedded pay sand 4 of Mississauga Formation. First, petrophysical parameters such as P and S wave impedances, Lamé’s parameters etc. are extracted from log data. Then, appropriate pairs of seismic attributes are crossplotted so that the hydrocarbon and non-hydrocarbon facies cluster together for quick identification and interpretation. Gamma ray index is crossplotted against spontaneous potential log to mark sand and shale facies. Fluid substitution modeling for various fluid types and saturation is also done which demonstrate that the cross-plots between different rock physics parameters can be used to distinguish between reservoir fluids. Our analysis reveals single P-wave based attributes are not sufficient to discriminate fluids thus the use of multi-attributes such as KP, λρ and Κ-μ is more effective to discriminate the hydrocarbon and non-hydrocarbon facies. The analysis of these cross-plots was done to map the reservoir sands and the hydrocarbon-water contact.

A dimensionality reduction-based efficient software fault prediction using Fisher linear discriminant analysis (FLDA)

Kalsoom, Anum,Maqsood, Muazzam,Ghazanfar, Mustansar Ali,Aadil, Farhan,Rho, Seungmin Springer-Verlag 2018 The Journal of supercomputing Vol.74 No.9

An application of rock physics modeling to quantify the seismic response of gas hydrate-bearing sediments in Makran accretionary prism, offshore, Pakistan

Muhammed Irfan Ehsan,Nisar Ahmed,Perveiz Khalid,Liu Xue Wei,Mustansar Naeem 한국지질과학협의회 2016 Geosciences Journal Vol.20 No.3

Naturally occurring gas hydrates are potential future energy source. A significant amount of gas hydrates is interpreted through seismic reflection data in the form of bottom simulating reflector (BSR) present in the sediments of the convergent continental margin of Pakistan. However, the seismic character of these hydratebearing unconsolidated sediments is not properly investigated. Since no direct measurements are available for quantitative estimation of gas hydrate and free gas in these sediments, therefore detailed knowledge of seismic velocities is essential. Seismic velocities of the gas hydrate-bearing sediments in the study area are estimated by using the effective medium theory and the fluid substitution modeling. The results show that the presence of gas hydrates increases the stiffness of the unconsolidated sediments; whereas the presence of free gas decreases the stiffness of these sediments. It is noted that seismic velocities and density of hydrate-bearing sediments are highly affected by saturation and distribution pattern of gas hydrates. The hydrate-bearing sediments seem to be characterized not only by high P-wave velocity (about 2800 m/s) but also by anomalously low S-wave velocity (about 850 m/s). As pure gas-hydrates have much higher seismic velocities than those of host sediments, presence of gas-hydrate increases the seismic velocities, whereas free-gas below the hydrate-bearing sediments decreases the velocities. Seismic reflection from the BSR exhibits a wide range of amplitude variation with offset characteristics, which depend upon the saturation and distribution of hydrates above and free gas below the BSR. We have also demonstrated that some attributes like acoustic and shear impedances, and AVO can be used as important proxies to detect gas hydrate saturation.

BiFeO3-based Z scheme photocatalytic systems: Advances, mechanism, and applications

Aastha Dhawan,Anita Sudhaik,Pankaj Raizada,Sourbh Thakur,Tansir Ahamad,Pankaj Thakur,Pardeep Singh,Chaudhery Mustansar Hussain 한국공업화학회 2023 Journal of Industrial and Engineering Chemistry Vol.117 No.-

Hitherto, heed has been paid substantially to concoct potential photocatalysts to counter the issues ofenvironmental degradation and energy crises. Amongst the plethora of photocatalysts, BiFeO3 (BFO)based photocatalysts are blooming as a centre of attraction due to fine chemical stability, and easy extraction. Also owing to a 2.2–2.8 electron volt (eV) narrow bandgap, BFO to has turned into a competent photocatalystfor efficient visible light absorption. So, keeping in mind the advantages of BFO and reviewingprevious reports, the present review offers a deep overview of conventional heterojunctions andadvanced Z-scheme heterojunctions. The main focus of the review is on BFO-based Z-scheme heterojunctionsalong with photocatalytic mechanisms and various applications. The successful construction ofBFO-based Z-scheme heterojunction eliminates drawbacks of bare BFO photocatalysts such as shortlivedcharge carriers, and high recombination rate, and also enhances light absorption of the system asa whole. Because of spatially separated oxidation and reduction sites and efficacious charge migration,BFO-based Z-scheme heterojunctions are proficient contenders among photocatalytic materials. Therefore, BFO-based Z-scheme heterojunctions are aptly used nowadays, in various fields like pollutantdegradation, wastewater treatment, organic synthesis, hydrogen production, and treatment ofantibiotics.

Magnetic molecularly imprinted polymer photocatalysts: synthesis, applications and future perspective

Komal Poonia,Pankaj Raizada,Archana Singh,Narinder Verma,Tansir Ahamad,Saad M. Alshehri,Aftab Aslam Parwaz Khan,Pardeep Singh,Chaudhery Mustansar Hussain 한국공업화학회 2022 Journal of Industrial and Engineering Chemistry Vol.113 No.-

Effective degradation of low-concentration pollutants is a critical challenge during the water purificationprocess. The use of different chemicals can leave residue in samples that can impose potential ecotoxicologicaland adverse impacts on human health. Presently, Magnetic molecularly imprinted polymers(MMIPs) have attracted much attention as the research material comprises a non-magnetic polymerand magnetic material for selective binding for target molecule and recoverability of catalyst via magnetism,respectively. This review explains the synergistic effect of adsorption with photocatalysis tounderstand their recognition mechanism and the possible interaction between the target molecule andMIPs. Then their common imprinting polymerization processes i.e., free radical polymerization andnon-free radical polymerization are briefly discussed with their respective advantages and disadvantages. In addition, this review highlights the photocatalytic degradation mechanism of photocatalyst cumadsorbent is critically discussed by comparing it with non-imprinted polymers. Finally, the applicationsof MMIPs in the removal or degradation of refractory pollutants, sensing, and recognition have alsobeen delineated. This paper summarises progressive future challenges of the technology that need tobe exploited for the preparation of the targeted catalyst.