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31.
Mahmood Toqeer Shah Mohsin Rashid Junaid Saba Tanzila Nisar Muhammad Wasif Asif Muhammad 《Multimedia Tools and Applications》2020,79(43-44):31759-31782
Multimedia Tools and Applications - Due to the recent evolutions in the technologies various digital devices and image processing tools are available in the market. Consequently, crime rates are... 相似文献
32.
Cheah Kit Hwa Nisar Humaira Yap Vooi Voon Lee Chen-Yi 《Neural computing & applications》2020,32(13):8867-8891
Neural Computing and Applications - This paper highlights the ability of convolutional neural networks (CNNs) at classifying EEG data listening to different kinds of music without the requirement... 相似文献
33.
Synthesis,characterization, and properties of new 3‐hexyl‐2,5‐diphenylthiophene: Phenylene vinylenes copolymers as colorimetric sensor for iodide anion
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Four new conjugated copolymers P1 ‐ P4 have been prepared by the Horner‐Emmons and Knoevenagel polymerization reactions. P1 ‐ P4 were characterized by NMR, FTIR, cyclic voltammetry (CV), diffuse reflectance UV–vis spectroscopy (DR UV–vis), and thermal gravimetric analysis (TGA). The optical band gaps of these polymers, calculated from the onset absorption edge, were found between 2.15 and 2.34 eV. The band gaps calculated by CV were ranged between 1.94 and 2.57 eV. The presence of nitrile moiety on the phenylene vinylene unit is believed to influence the optical properties of these polymers, i.e., P3 and P4 have shown lower band gaps than P1 and P2 . All polymers possess good iodide anion sensing property over a wide range of other anions (F?, Cl?, Br?, , CN?), indicating their promise in fabricating selective iodide sensors. The initial colorless solution of polymers in THF changed to deep yellow upon the addition of aqueous solution of iodide salts along with significant changes in the UV–vis spectra of the polymers. The limit of detection (LOD) for P1‐P4 were found between 0.43 and 2.54 mM . These polymers constitute long alkoxy and alkyl side chains, bearing excellent solubility in most common organic solvents which warrants their suitability for photovoltaic devices application. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 44948. 相似文献
34.
Muhammad Mansha Ibrahim Khan Nisar Ullah Ahsanulhaq Qurashi 《International Journal of Hydrogen Energy》2017,42(16):10952-10961
Hydrogen (H2) is one of the most important fuel candidates and its low-cost production would necessitate the development of efficient electrocatalysts. In this study, we report the synthesis and evaluation of two new carbazole-containing polymers as organic photoelectrochemical (PEC) catalysts for hydrogen evolution reaction (HER). The synthesis of these new conjugated polymers, poly(N-(2-ethylhexyl)-3,6-carbazole-p-bisdodecyloxy-phenylene vinylene) (P1) and poly(N-(2-ethylhexyl)-3,6-carbazole-p-bis(2-ethylhexyloxy)-phenylene vinylene) (P2), was accomplished by the Horner–Emmons polymerization reaction and subsequently characterized by 1H NMR, FTIR, diffuse reflectance UV–vis spectroscopy (DR UV–vis), scanning electron microscope (SEM) and thermogravimetric analysis (TGA). The optical band gaps of P1 and P2, derived from the onset absorption edge, were found to be 2.10 and 2.14 eV, respectively. The chronoamperometric (CA) measurements revealed that the photo-current density generated at ~0 V by P1 and P2, without the use of additional noble metal based cocatalysts or sacrificial electron donors, was ?1.8 and ?2.1 μA/cm2, respectively. The enhanced PEC performance of P2 was attributed due to its narrow band gap that enhanced light harvesting ability and the larger surface area which helped in minimizing charge recombination. The experimental observations were well supported by the drastic quenching of PL emission intensity of P2. The linear sweep voltammetry (LSV) measurements showed the onset potential at around ?0.3 V for both polymers. The photocurrent density difference for P2 at ?1.2 V reached to maximum value of 0.37 mA/cm2, amounting to ~25% current enhancement under illumination. Long-term stability testing via CA measurements revealed that P2 was relatively more stable than P1, which warranted its potential as photocatalyst for solar water splitting. In addition, P1 and P2 are readily soluble in common organic solvents which make them potential candidates for photovoltaic devices application. 相似文献
35.
Waqar Ahmad Kaleem Muhammad Nisar Mughal Qayum Muhammad Zia-Ul-Haq Achyut Adhikari Vincenzo De Feo 《International journal of molecular sciences》2012,13(9):11520-11529
Two new 14-membered cyclopeptide alkaloids, Oxyphylline B (4) and Oxyphylline C (5), along with three known 13-membered cyclopeptide alkaloids, were isolated from stem and roots of Zizyphus oxyphylla Edgew. The compounds were tested for antibacterial activity. Oxyphylline B (4) showed comparatively better antibacterial activities against Escherichia coli (MIC, 5 μg/mL) than other compounds. This compound also exhibited weak antimicrobial activities against Staphylococcus aureus (MIC, 25 μg/mL), Pseudomonas aeruginosa (MIC, 50 μg/mL) and Salmonella typhi (MIC, 50 μg/mL). 相似文献
36.
Effect of high temperature on grain filling period,yield, amylose content and activity of starch biosynthesis enzymes in endosperm of basmati rice 总被引:4,自引:0,他引:4
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37.
A natural dye was extracted from Eucalyptus camaldulensis and was used to dye cotton by direct dyeing method at different dyeing conditions. Then, the fastness properties of dyeing with different dyeing techniques were compared. 相似文献
38.
Nisar Fatima Muhammad Bilal Tahir Asma Noor M. Sagir M. Suleman Tahir Hussein Alrobei Urooj Fatima Khurram Shahzad Arshid Mahmood Ali Shabbir Muhammad 《International Journal of Hydrogen Energy》2021,46(50):25413-25423
Recently, photocatalysis has received huge attention in order to overcome energy crisis worldwide. Many semiconductors, potential schemes and hierarchies have come to light during past few decades to fabricate efficient catalysts however, among all these methods heterostructures have taken the world by surprise. With the advancement in post-graphene 2D materials, van der Waals heterostructures have come to light exploring enhancement in photocatalysis. During a very short period a number of ZnO-based van der Waal heterostructures have taken the limelight in the field of photocatalysis. First principles calculations and DFT approach towards the heterostructures of GeC, GaN, WSe2, WS2 and other layered 2D materials unleased a series of properties and facts for the provision of enhanced catalysis. Reduction in bandgap of ZnO has also been observed which widens the pathways towards visible light irradiation. However, energy applications of zinc oxide are also fascinating feature as it can serve as a photoanode to replace TiO2. Whereas the famous hydrogen production, batteries and solar cells have also been fabricated by the use of this semiconductor. 相似文献
39.
Sabah Nisar Parvaiz Yousuf Tariq Masoodi Nissar A. Wani Sheema Hashem Mayank Singh Geetanjali Sageena Deepika Mishra Rakesh Kumar Mohammad Haris Ajaz A. Bhat Muzafar A. Macha 《International journal of molecular sciences》2021,22(9)
Head and neck squamous cell carcinomas (HNSCCs) are aggressive diseases with a dismal patient prognosis. Despite significant advances in treatment modalities, the five-year survival rate in patients with HNSCC has improved marginally and therefore warrants a comprehensive understanding of the HNSCC biology. Alterations in the cellular and non-cellular components of the HNSCC tumor micro-environment (TME) play a critical role in regulating many hallmarks of cancer development including evasion of apoptosis, activation of invasion, metastasis, angiogenesis, response to therapy, immune escape mechanisms, deregulation of energetics, and therefore the development of an overall aggressive HNSCC phenotype. Cytokines and chemokines are small secretory proteins produced by neoplastic or stromal cells, controlling complex and dynamic cell–cell interactions in the TME to regulate many cancer hallmarks. This review summarizes the current understanding of the complex cytokine/chemokine networks in the HNSCC TME, their role in activating diverse signaling pathways and promoting tumor progression, metastasis, and therapeutic resistance development. 相似文献
40.
Sidra Nisar Ahmed Mushtaq Ahmad Ghulam Yaseen Muhammad Zafar Sofia Rashid Abdul Nazir Shazia Sultana Farida Anjum Fethi Ahmet Ozdemir Omer Kilic 《Microscopy research and technique》2021,84(1):28-37
The quality assurance and authentication of crude herbal drugs play important role in the effective therapeutic effect of herbal drug and their products. There are many reported problems in quality assurance of herbal crude drugs concerning to their correct identification. The present study was designed with the aim to document the authentication and quality assurance of the herbal crude drugs (Argyrolobium roseum and Viola stocksii) thorough light microscopy (LM) and scanning electron microscopy (SEM). The detailed foliar anatomical studies showed polygonal epidermal cells having anticlinal walls in Argyrolobium roseum while rounded epidermal cells were observed in Viola stocksii. The anomocytic stomata type was observed in Argrolobium roseum while actinocytic was noticed in Viola stocksii. The pollen of studied species appeared as tricolporate showing reticulate exine sculpturing in Argrolobium roseum while fine perforations were recorded in Viola stocksii. Furthermore, quantitative analysis of phenols, flavonoids, and antioxidant activity showed high flavonoid and phenol content in Argyrolobium roseum as compared with Viola stocksii. It was observed that Argyrolobium roseum was discriminated from the Viola stocksii based on the leaf and pollen micromorphological traits by using LM and SEM techniques. It was concluded that LM and SEM techniques were found useful for the quality assurance of botanicals and their authentication. 相似文献