239 results on '"Ahmad, Umar"'
Search Results
2. Synergistic electrochemical sensing of 2,4-dinitrotoluene via bimetallic nickel-cobalt oxide nanoparticles
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Bharti Sharma, Shikha Jain, Ahmad Umar, Sushma Rani, Sandeep Kumar, Ahmed A. Ibrahim, and Neeraj Dilbaghi
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Electrochemical sensing ,Bimetallic nanoparticles ,Nickel-cobalt oxide ,2,4-Dinitrotoluene ,Ultrasensitive detection ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
This study presents a comprehensive investigation into the synthesis, characterization, and application of an exceptionally sensitive electrochemical sensor designed for the ultrasensitive detection of 2,4-dinitrotoluene (DNT), a notorious explosive compound. The sensor employs bimetallic nickel-cobalt oxide (NiCo2O4) nanoparticles, synthesized through a facile hydrothermal method. Extensive analytical techniques, including scanning electron microscopy (SEM), transmission electron microscopy (TEM), atomic force microscopy (AFM), and x-ray photoelectron spectroscopy (XPS), were employed to validate the crystallinity and purity of the NiCo2O4 nanoparticles. These nanoparticles, possessing remarkable properties, form the core of our electrochemical sensor, enabling it to offer heightened sensitivity and selectivity even under ambient conditions. Most notably, this sensor boasts an impressively low limit of detection (LOD) of 18 nM, coupled with a broad linear detection range (LDR) spanning from 10 nM to 100 nM. The sensor exhibits robust sensitivity, excellent selectivity, and an outstandingly low detection threshold, collectively demonstrating its potential for precise and accurate detection of DNT. This research underscores the significant potential of bimetallic oxide nanoparticles, specifically NiCo2O4, in the precise quantification of nitro-aromatic analytes. This study opens up promising avenues for assessing hazardous compounds in complex environmental matrices, thereby contributing to the advancement of electrochemical sensing. Additionally, this novel sensing platform holds substantial promise for enhancing security measures and environmental monitoring through its improved sensitivity and selectivity in the detection of explosives.
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- 2024
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3. Enhanced CO sensing with highly sensitive and selective rGO-Ru OEP chemiresistive sensor
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Yogita A. Waghmare, Vijaykiran N. Narwade, Ahmad Umar, Ahmed A. Ibrahim, and Mahendra D. Shirsat
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Reduced graphene oxide ,Ruthenium octaethyl porphyrin ,Chemiresistive sensor ,Carbon monoxide sensor ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
The escalating discharge of noxious gases resulting from unmitigated anthropogenic activities has emerged as a pivotal concern, presenting imminent threats to global ecosystems. In response to this pressing challenge, the development of cutting-edge materials within gas sensor systems emerges as a promising avenue for the precise detection of hazardous gaseous pollutants. This investigation delves into the synthesis and characterization of a novel composite material: reduced graphene oxide (rGO) modified with ruthenium Octaethyl porphyrin (Ru OEP), with a primary focus on its chemiresistive sensing properties. The meticulously deposited rGO-modified Ru OEP material onto gold microelectrodes, featuring a 3 µm gap on a silicon Si/SiO2 substrate, resulted in an intricate two-terminal chemiresistive sensor device. Comprehensive structural, spectroscopic, and morphological analyses were conducted to elucidate the intricacies of the composite material. The electrical characterization, evaluated through I-V measurements, provided nuanced insights into the device's resistance properties. Notably, the chemiresistive sensor demonstrated exceptional responsiveness to Carbon monoxide (CO) gas, exhibiting an impressively low limit of detection (LOD) at 2.5 ppm. The fabricated sensor showcased rapid response and recovery times, registering at 43 s and 65 s, respectively, underscoring its efficiency in real-time applications. Furthermore, the sensor maintained linearity and stability across a broad spectrum of conditions, ensuring prolonged reliability and consistent performance. This research underscores the potential of advanced materials, specifically the rGO-modified Ru OEP composite, in crafting highly effective gas sensors to address urgent environmental and safety concerns. The presented findings contribute invaluable insights to the burgeoning field of gas sensor technology, paving the way for innovative solutions to mitigate the adverse impacts of anthropogenic activities on our delicate ecosystems.
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- 2024
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4. 2D NiMoO4 nanowalls directly grown on Ni foam for the asymmetric electrochemical supercapacitors
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Ha-Ryeon Lee, M. Shaheer Akhtar, Ahmad Umar, Ahmed A. Ibrahim, Sotirios Baskoutas, and O-Bong Yang
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NiMoO4 ,Thin film ,Electrode ,Electrochemical properties ,Supercapacitors ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Significant advances in the field of energy storage have enabled scientists to explore highly stable electro-active electrodes for high-performance supercapacitors. The present investigation describes the synthesis of well-ordered NiMoO4 nanowalls at 140 °C using hydrothermal synthesis, which was then grown directly on Ni foam with different reaction times. The resulting NiMoO4 nanowalls were utilized as electro-active electrodes for electrochemical supercapacitor applications. The reaction time was found to be a critical factor in achieving the ordered NiMoO4 nanowalls on the Ni foam, and at a reaction time of 12 h, the nanosheets self-organized into a nanowall-like morphology over the Ni foam. Pure NiMoO4 crystal phases with less surface imperfections were produced by the 12-hour reaction time, as demonstrated by the compositional, structural, and crystalline characteristics. As an electro-active electrode, the NiMoO4 electrode with a 12-hour reaction time showed the highest specific capacitance of 357.6 Fg−1 at 0.01 Vs−1 compared to NiMoO4 electrodes with reaction times of 6h (53.06 Fg-1 at 0.01 Vs−1) and 20h (55.4 Fg-1 at 0.01 Vs−1). The NiMoO4 electrode also demonstrated exceptional stability in an alkaline electrolyte, exhibiting less deterioration in multicycles CV after 100 repeated cycles. The excellent electrochemical properties of the NiMoO4 electrode are attributed to its unique ordered nanowall structure, which improves surface area and electrical conduction, accelerating fast redox reactions. These properties make it a promising material for use in pseudocapacitors, with implications for high-performance energy storage solutions in industrial sectors.
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- 2024
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5. Assessing the potential of ionosonde for forecasting post-sunset equatorial spread F: an observational experiment in Southeast Asia
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Abadi, Prayitno, Ali Ahmad, Umar, Otsuka, Yuichi, Jamjareegulgarn, Punyawi, Almahi, Alif, Perwitasari, Septi, Supriadi, Slamet, Harjupa, Wendi, and Septiawan, Reza Rendian
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- 2023
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6. Analysis of PPI networks of transcriptomic expression identifies hub genes associated with Newcastle disease virus persistent infection in bladder cancer
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Ahmad, Umar, Abdullah, Syahril, Chau, De Ming, Chia, Suet Lin, Yusoff, Khatijah, Chan, Soon Choy, Ong, Teng Aik, Razack, Azad Hassan, and Veerakumarasivam, Abhi
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- 2023
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7. The impact of green credit legislation on business financing: Insights from Chinese polluting firms
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Hu, Naixin and Ahmad, Umar Suffian
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- 2024
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8. Liner shipping connectivity: A dynamic link between energy trade, green exchange and inclusive growth using advanced econometric modelling
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Jin, Yingying, Li, Heng, Yu, Yi, and Ahmad, Umar Suffian
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- 2024
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9. Role of the IL8 rs4073 polymorphism in central nervous system toxicity in patients receiving multidrug-resistant tuberculosis treatment
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Ibrahim Mohammed Badamasi, Muktar Muhammad, Aishat Ahmad Umar, Umm-ayman Misbahu Madugu, Muktar Ahmed Gadanya, Isa Abubakar Aliyu, Imam Malik Kabir, Ibrahim Aliyu Umar, Ochigbo Johnson, and Johnson Stanslas
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Tuberculosis, multidrug-resistant ,Immunity ,Pharmacogenetics ,Polymerase chain reaction ,Risk ,Diseases of the respiratory system ,RC705-779 - Abstract
ABSTRACT Objective: To determine the role of the IL8 rs4073 polymorphism in predicting the risk of central nervous system (CNS) toxicity in patients receiving standard pharmacological treatment for multidrug-resistant tuberculosis (MDR-TB). Methods: A cohort of 85 consenting MDR-TB patients receiving treatment with second-line antituberculosis drugs had their blood samples amplified for the IL8 (rs4073) gene and genotyped. All patients were clinically screened for evidence of treatment toxicity and categorized accordingly. Crude and adjusted associations were assessed. Results: The chief complaints fell into the following categories: CNS toxicity; gastrointestinal toxicity; skin toxicity; and eye and ear toxicities. Symptoms of gastrointestinal toxicity were reported by 59% of the patients, and symptoms of CNS toxicity were reported by 42.7%. With regard to the genotypes of IL8 (rs4073), the following were identified: AA, in 64 of the study participants; AT, in 7; and TT, in 11. A significant association was found between the dominant model of inheritance and CNS toxicity for the crude model (p = 0.024; OR = 3.57; 95% CI, 1.18-10.76) and the adjusted model (p = 0.031; OR = 3.92; 95% CI, 1.13-13.58). The AT+TT genotype of IL8 (rs4073) showed a 3.92 times increased risk of CNS toxicity when compared with the AA genotype. Conclusions: The AT+TT genotype has a tendency to be associated with an increased risk of adverse clinical features during MDR-TB treatment.
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- 2024
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10. Influence of carbon nanotube suspensions on the structural, optical, and electrical properties of grown ZnO nanorods
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Abdulhameed, Abdullah, Halim, Mohd Mahadi, Wan Ahmad Kamil, Wan Maryam, Zheng, Kevin Ooi, Ahmad, Ahmad Umar, and Alsaee, Saleh K.
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- 2023
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11. Nanomaterials-based biosensor and their applications: A review
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Sumit Malik, Joginder Singh, Rohit Goyat, Yajvinder Saharan, Vivek Chaudhry, Ahmad Umar, Ahmed A. Ibrahim, Sheikh Akbar, Sadia Ameen, and Sotirios Baskoutas
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Nanowires ,Nanorods ,Carbon nanotubes ,Quantum dots ,Dendrimers ,Science (General) ,Q1-390 ,Social sciences (General) ,H1-99 - Abstract
A sensor can be called ideal or perfect if it is enriched with certain characteristics viz., superior detections range, high sensitivity, selectivity, resolution, reproducibility, repeatability, and response time with good flow. Recently, biosensors made of nanoparticles (NPs) have gained very high popularity due to their excellent applications in nearly all the fields of science and technology. The use of NPs in the biosensor is usually done to fill the gap between the converter and the bioreceptor, which is at the nanoscale. Simultaneously the uses of NPs and electrochemical techniques have led to the emergence of biosensors with high sensitivity and decomposition power. This review summarizes the development of biosensors made of NPssuch as noble metal NPs and metal oxide NPs, nanowires (NWs), nanorods (NRs), carbon nanotubes (CNTs), quantum dots (QDs), and dendrimers and their recent advancement in biosensing technology with the expansion of nanotechnology.
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- 2023
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12. Facile auto-flash-combustion synthesis and characterization of visible-light-driven photocatalytic active Mn (II, III) loaded NiO nanoparticles
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Mohd. Shkir, Kamlesh V. Chandekar, Baskaran Palanivel, Fatemah H. Alkallas, Amira Ben Gouider Trabelsi, Aslam Khan, S. AlFaify, Ahmad Umar, Ahmed A. Ibrahim, and S. Baskoutas
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Mn-doped NiO nanostructures ,Structural properties ,Optical properties ,Photocatalysis ,Wastewater treatment ,Materials of engineering and construction. Mechanics of materials ,TA401-492 - Abstract
The opto-photocatalytic applications of Mn-doped NiO nanoparticles (NPs) are discussed. A facile synthesis of NiO doped with different Mn contents is performed and studied using experimental techniques. The structural properties and microstructural parameters of Mn:NiO NPs were examined by X-ray diffraction patterns. The average crystallite sizes of the pure NiO and 1.0-, 2.5-, 5.0-, 10-wt.% Mn-doped NiO NPs were found to be 25–19 nm by Williamson–Hall plots and 23–18 nm by the Debye–Scherer method. The crystallite size decreases with increasing doping concentration in the NiO host lattice. The optical bandgaps are found to be 3.53, 3.46, 3.39, 3.24, and 3.12 eV for pure NiO and 1.0-, 2.5-, 5.0-, and 10-wt.% Mn:NiO NPs, respectively, using the Kubelka–Munk function. X-ray photoelectron spectroscopy spectra of 2.5-wt.% Mn:NiO NPs were recorded for Mn, Ni, and O to determine the oxidation states. The photocatalytic performances of pure NiO and Mn:NiO NPs are examined. The 2.5-wt.% Mn:NPs exhibit the best photocatalytic performance owing to the greatest activation sites. The mechanism of the photocatalytic decolorization reaction is also investigated. The results demonstrate the high ability of Mn:NiO NPs as photocatalysts for methylene blue dye degradation, with 92% removal.
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- 2023
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13. Extreme precipitation over complex terrain using multiple remote sensing observation: A case study in the Great Bandung, Indonesia
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Sinatra, Tiin, Nugroho, Ginaldi Ari, Halimurrahman, Cholianawati, Nani, Indrawati, Asri, Renggono, Findy, Yulihastin, Erma, Lestari, Sopia, Ahmad, Umar Ali, Widada, Wahyu, and Awaludin, Asif
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- 2023
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14. A SWOT Analysis Approach for the Development of Photovoltaic (PV) Energy in Northern Nigeria
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Bisu, Anas A., Ahmed, Tariq G., Ahmad, Umar S., and Maiwada, Abubakar D.
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- 2024
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15. A QOBL-SAO and its variant: An open source software for optimizing PV/wind/battery system and CEC2020 real world problems.
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Abdullahi Abubakar Mas'ud, Ahmed T. Salawudeen, Abubakar Ahmad Umar, Yusuf A. Sha'aban, Firdaus Muhammad-Sukki, Umar Musa, and Saud J. Alshammari
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- 2024
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16. Development of automated impact system for modal analysis of micro-end mill
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Gururaja, S., Ahmad, Umar, and Singh, Kundan K.
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- 2023
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17. A comprehensive review of cystic fibrosis in Africa and Asia
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Abubakar Bobbo, Khadijat, Ahmad, Umar, Chau, De-Ming, Nordin, Norshariza, and Abdullah, Syahril
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- 2023
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18. Pendampingan Basic Arabic Club Pada Anak Usia Dini Di Desa Sidomulyo Kelurahan Tumbang Tahai Kota Palangka Raya
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Ahmad Umar Faruq, Nurul Wahdah, and Muslimah Muslimah
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kata kunci: basic arabian club, pendampingan, bahasa arab ,Sociology (General) ,HM401-1281 ,Islam ,BP1-253 - Abstract
Bahasa Arab merupakan bahasa Al-Qur’an dan Hadits. kewajiban mempelajarinya bagi setiap umat muslim agar dapat memahami Al-Quran dan Hadits secara baik dan benar. Tetapi, bahasa Arab kini kurang diminati karena kesukarannya yang tinggi dan membutuhkan waktu yang lama untuk mempelajarinya. Seperti yang terjadi pada masyarakat Desa Sidomulyo, Kelurahan Tumbang Tahai, Kota palangka Raya. Keterbatasan SDM juga menjadi kendala tambahan dalam mempelajari bahasa Arab. Pengabdian ini bertujuan memberikan pendampingan dalam pembelajaran bahasa Arab tingkat dasar kepada anak-anak di Desa Sidomulyo, Kelurahan Tumbang Tahai, Kota palangka Raya untuk menumbuhkan minat dan memberikan pemahaman pentingnya mempelajari bahasa Arab. Pendampingan ini dilakukan dengan membentuk sebuah program pembelajaran bahasa Arab yang dinamakan basic Arabic Club. Metode yang digunakan pada pengabdian ini adalah dengan metode service learning. Dari hasil pendampingan yang dilakukan selama tiga minggu melalui program basic Arabic club Nampak adanya peningkatan minat dan pengetahuan basic bahasa Arab terhadap peserta didik. Peserta didik dapat menghafal dan mengaplikasikan kosa kata bahasa Arab, memahami beberapa materi dasar Nahwu dan Shorof, dapat menulis Arab dengan baik dan memiliki peningkatan minat Seperti keinginan mereka untuk masuk pesantren guna mendalami bahasa Arab.
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- 2022
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19. Electrospun Co3O4 nanofibers as potential material for enhanced supercapacitors and chemo-sensor applications
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Ahmad Umar, M. Shaheer Akhtar, Ahmed A. Ibrahim, Hassan Algadi, Mohsen A.M. Alhamami, Faheem Ahmed, Moaaed Motlak, and Sheikh Akbar
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Co3O4 nanofibers ,Electrospinning ,Electrochemical ,Chemo-sensor ,Supercapacitors ,Mining engineering. Metallurgy ,TN1-997 - Abstract
In this paper, highly dense and defined Co3O4 nanofibers were prepared by electrospinning method followed by controlled oxidation using polyvinylpyrrolidone (PVP) and CoCl2 as precursors. For the fabrication of effective electrochemical sensors and supercapacitors, the prepared Co3O4 nanofibers were used as electro-active electrodes. The prepared Co3O4 nanofibers were morphologically investigated by field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) which confirmed the formation of highly dense and well-defined fibrous morphology. The X-ray diffraction (XRD) and elemental analysis demonstrated the typical crystalline cubic phase Co3O4 with appropriate stoichiometric element ratio. The supercapacitor with prepared Co3O4 nanofibers based electrode has an excellent cycle stability and a considerably higher specific capacitance of 419 C/g at a current density of 0.5 A/g. Interestingly, the fabricated supercapacitor device keeps 87% capacitance after 5000 charge/discharge cycles. For 2-butanone chemical sensing, the prepared Co3O4 nanofibers based electrode presents a reasonable sensitivity of 90.7 mAμM−1cm−2 and linear dynamics of 10–200 μM with good LOD of ∼5.8 μM and regression coefficient (R) = ∼0.97407. Thus, the prepared Co3O4 nanofibers with highly porous surface would pave the direction to the manufacturing of efficient energy storage and electrochemical sensing materials.
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- 2022
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20. Heterogeneous effect of oil production on environmental degradation: panel evidence from OPEC member countries
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Danmaraya, Ismail Aliyu, Jakada, Aminu Hassan, Mahmood, Suraya, Ibrahim, Bello Alhaji, and Ali, Ahmad Umar
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- 2022
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21. A review on the clean-up technologies for heavy metal ions contaminated soil samples
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Vikas Kumar, Chadetrik Rout, Joginder Singh, Yajvinder Saharan, Rohit Goyat, Ahmad Umar, Sheikh Akbar, and S. Baskoutas
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Heavy metal ions ,Lung cancer ,Remediation technology ,Contaminated soil ,Permissible limits ,And feasibility ,Science (General) ,Q1-390 ,Social sciences (General) ,H1-99 - Abstract
The soil contamination with heavy metal ions is one of the grave intricacies faced worldwide over the last few decades by the virtue of rapid industrialization, human negligence and greed. Heavy metal ions are quite toxic even at low concentration a swell as non-biodegradable in nature. Their bioaccumulation in the human body leads to several chronic and persistent diseases such as lung cancer, nervous system break down, respiratory problems and renal damage etc. In addition to this, the increased concentration of these metal ions in soil, beyond the permissible limits, makes the soil unfit for further agricultural use. Hence it is our necessity, to monitor the concentration of these metal ions in the soil and water bodies and adopt some better technologies to eradicate them fully. From the literature survey, it was observed that three main types of techniques viz. physical, chemical, and biological were employed to harness the heavy metal ions from metal-polluted soil samples. The main goal of these techniques was the complete removal of the metal ions or the transformation of them into less hazardous and toxic forms. Further the selection of the remediation technology depends upon different factors such as process feasibility/mechanism of the process applied, nature and type of contaminants, type and content of the soil, etc. In this review article, we have studied in detail all the three technologies viz. physical, chemical and biological with their sub-parts, mechanism, pictures, advantages and disadvantages.
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- 2023
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22. Determinants of renewable energy sources in Pakistan: An overview
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Ahmad, Umar Suffian, Usman, Muhammad, Hussain, Saddam, Jahanger, Atif, and Abrar, Maira
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- 2022
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23. Co-Circularly Polarized Planar Antenna With Highly Decoupled Ports for S-Band Full Duplex Applications.
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Haq Nawaz, Ahmad Umar Niazi, Ahsen Tahir, Noman Ahmad, Usman Masud, Turke Althobaiti, Abdullah Alhumaidi Alotaibi, and Naeem Ramzan
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- 2022
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24. The Public Information Disclosure in State Madrasah Aliyah
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Ahmad Umar, Muhammad Munadi, Aminuddin Aminuddin, and Tato Priyo Sulistyono
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Public Information Disclosure ,Institutional Dimension ,Institutional Actors ,Good Institution ,Education ,Islam ,BP1-253 - Abstract
This study aimed to determine the implementation model of public information disclosure at MAN 2 Pesisir Selatan in West Sumatra province. This study used content analysis research with the data originating from websites, along with the documents and developments downloaded from the websites related to public information disclosure activities at MAN 2 Pesisir Selatan. This study was conducted from November to December 2022. The data validity used source triangulation by validating data in documents on the websites under study in one feature and across features. The data were analyzed using an interactive analysis model. The results show that the public information disclosure implemented in MAN 2 Pesisir Selatan was through providing a place and the main website connected to the PPID website. The PPID website contained complete profiles and types of report information following existing regulations. There were types of information and reports with institutional dimensions, and institutional actors, so good and clean institutions could reflect excellent and clean executors.
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- 2023
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25. ZIF‐8 Composites for the Removal of Wastewater Pollutants.
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Ahmad, Umar, Ullah, Sami, Rehman, Azizur, Najam, Tayyaba, Alarfaji, Saleh S, Jamshaid, Muhammad, Parkash Kumar, Ome, Ullah, Sultan, Shahid, Misbah, Ahmad Shah, Syed Shoaib, and Altaf Nazir, Muhammad
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POLLUTANTS , *SEWAGE , *METAL-organic frameworks , *ADSORPTION capacity , *WASTEWATER treatment - Abstract
The presence of dyes in wastewater poses a significant environmental challenge due to their permanence toxicity and potential to harm ecosystems. Because of their high porosity and adjustable characteristics, metal‐organic frameworks (MOFs) have become attractive materials for effective dye removal. Among various MOFs, zeolitic imidazolate frameworks (ZIFs) have garnered significant attention, especially ZIF‐8, for its excellent stability, significant porosity, adjustable pore size and remarkable adsorption capacity. This review article provides a comprehensive overview of recent advances in the implementation of ZIF‐8 and its composites for the removal of pollutants from wastewater. The various synthesis methods, structural characteristics and dye adsorption performance of ZIF‐8 and its composites are discussed. Furthermore, impact of the different factors such as pH, temperature, dye concentration, contact time etc. were also highlighted. Moreover, the detailed adsorption mechanism was also discussed. Finally, the current challenges and future perspectives in the production of materials based on ZIF‐8 for the removal of dyes were also presented. [ABSTRACT FROM AUTHOR]
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- 2024
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26. Transcriptome profiling research in urothelial cell carcinoma.
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Ahmad, Umar, Ibrahim, Buhari, Mohammed, Mustapha, Aldoghachi, Ahmed Faris, Usman, Mahmood, Yakubu, Abdulbasit Haliru, Tanko, Abubakar Sadiq, Bobbo, Khadijat Abubakar, Garkuwa, Usman Adamu, Faggo, Abdullahi Adamu, Mustapha, Sagir, Al‐Masaeed, Mahmoud, Abdullah, Syahril, Keong, Yong Yoke, and Veerakumarasivam, Abhi
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TRANSITIONAL cell carcinoma ,NUCLEOTIDE sequencing ,TRANSCRIPTOMES ,TECHNOLOGICAL innovations ,BLADDER cancer - Abstract
Urothelial cell carcinoma (UCC) is the ninth most common cancer that accounts for 4.7% of all new cancer cases globally. UCC development and progression are due to complex and stochastic genetic programs. To study the cascades of molecular events underlying the poor prognosis that may lead to limited treatment options for advanced disease and resistance to conventional therapies in UCC, transcriptomics technology (RNA‐Seq), a method of analyzing the RNA content of a sample using modern high‐throughput sequencing platforms has been employed. Here, we review the principles of RNA‐Seq technology and summarize recent studies on human bladder cancer that employed this technique to unravel the pathogenesis of the disease, identify biomarkers, discover pathways and classify the disease state. We list the commonly used computational platforms and software that are publicly available for RNA‐Seq analysis. Moreover, we discussed the future perspectives for RNA‐Seq studies on bladder cancer and recommended the application of a new technology called single‐cell sequencing to further understand the disease. [ABSTRACT FROM AUTHOR]
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- 2024
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27. Keabsahan Akta Berita Acara Rapat Umum Pemegang Saham Perseroan Terbatas yang Dibuat Melalui Media Elektronik
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Ahmad Umar Farhan Tuasikal
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legality, cyber notary, deed of minutes ,Law in general. Comparative and uniform law. Jurisprudence ,K1-7720 ,Social sciences (General) ,H1-99 - Abstract
This study aimed to analyze the authority of a notary in making the minutes of the general meeting of shareholders of a limited liability company through electronic media and the legality of a notary deed related to the signing of a general meeting of shareholders of a limited liability company through electronic media. This study used a statutory research approach, with normative legal research—data collection techniques using literature study. The data was sourced from books and statutory documents. The results of this study indicated that the authority of a notary in making official reports using electronic media was regulated in Article 15 paragraph (3) of Law Number 2 of 2014 concerning Notary Positions, Article 77 paragraph (1) of Law Number 40 of 2007 concerning Limited Liability Companies, and Article 5 paragraph (1) of Law Number 19 of 2016 concerning Electronic Transaction Information. To conclude, minutes of the general meeting of shareholders held by teleconference or video conference still have legal force as an authentic deed.
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- 2021
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28. Knowledge, Attitude and Practices Toward Coronavirus Disease (COVID- 19) in Southeast and South Asia: A Mixed Study Design Approach
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Mohammad Meshbahur Rahman, Roy Rillera Marzo, Shanjida Chowdhury, Sikandar Ali Qalati, Mohammad Nayeem Hasan, Gowranga Kumar Paul, Khadijah Abid, Wegayehu Enbeyle Sheferaw, Angela Mariadass, Divitra Chandran, Shasvini Kanan, Ahmad Umar Shafie Bin Ahmad Firdaus, Fatimah Az Zahra' binti Sabarin, and Yulan Lin
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COVID–19 ,knowledge ,attitude ,practice ,Southeast and South Asia ,Public aspects of medicine ,RA1-1270 - Abstract
BackgroundCoronavirus has spread to almost every country since its emergence in Wuhan, China and countries have been adopted an array of measures to control the rapid spread of the epidemic. Here, we aimed to assess the person's knowledge, attitude and practices (KAP) toward the COVID-19 epidemic in Southeast and South Asia applying the mixed study design (cross-sectional and systematic review).MethodsIn the cross-sectional study, 743 respondents' socio-demographic and KAP-related information was collected through an online population-based survey from the Malaysian population. In the systematic review, the database PubMed, Web of Science and Google Scholar search engine were searched and related published articles from South and Southeast Asia were included. Frequency distribution, Chi-square association test and binary logistic regression were fitted using cross-sectional data whereas random effect model and study bias were performed in meta-analysis. We used 95% confidence interval and P
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- 2022
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29. Radiation attenuation properties of the quaternary semiconducting compounds Cu2CoGe[S, Se, Te]4
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H.Y. Zahran, M.I. Mohammed, El Sayed Yousef, Mohammed S. Alqahtani, Manuela Reben, H. Algarni, Ahmad Umar, Hasan B. Albargi, I.S. Yahia, Mohamed Sh. Abdel-wahab, and Medhat A. Ibrahim
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Compound semiconductors ,MAC ,Radiation shielding ,Zeff ,Effective conductivity ,Photon and charged particles ,Physics ,QC1-999 - Abstract
The radiation-protection properties of the magnetic semiconducting quaternary compounds Cu2CoGeS4, Cu2CoGeSe4, and Cu2CoGeTe4 were examined in this study by using Phy-X/PSD software with the selected gamma energy (0.015–15 MeV). The radiation shielding coefficients such as mass and linear attenuation coefficients (MAC) and (LAC), half-value layer (HVL), and mean free path (MFP) of the present semiconductors were calculated. Also, the total electronic and atomic cross-sections (ECS and ACS), the effective atomic number (Zeff), the effective electron density (Neff), and the effective conductivity (Ceff) of these semiconductors were estimated to see how well they could protect against radiation. A comparative study occurred between the obtained results and the corresponding values of RS-253-G18, RS-360, RS-520 glasses, barite, chromite, and ferrite concrete. The results show that semiconducting samples with the best shielding performance outperform RS-253-G18, RS-360 glass, and RS-520 glass materials commonly used in nuclear applications. The Cu2CoGeTe4 sample had the highest MAC, LAC, and ACS, as well as the highest ECS and Zeff values. The other two semiconductor samples had the lowest MAC, ECS, and Zeff values. For photons, charged particles (electrons, protons, alpha particles), and C-ion, Phy-X/PSD allows the calculation of the Zeff quickly and precisely across the entire energy range. This study indicates that the semiconductor samples can be utilized as radiation attenuators for various nuclear fields.
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- 2022
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30. Solvatochromism as a Novel Tool to Enumerate the Optical and Luminescence Properties of Plastic Waste Derived Carbon Nanodots and Their Activated Counterparts
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Savita Chaudhary, Manisha Kumari, Pooja Chauhan, Ganga Ram Chaudhary, Ahmad Umar, Sheikh Akbar, and Sotirios Baskoutas
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carbon dots ,activated carbon ,transition state ,excitation emission ,stoke shift ,Chemistry ,QD1-999 - Abstract
Herein, we have developed a one-pot methodology to synthesise three types of C-dots and their activated counterparts from three different types of waste plastic precursors such as poly-bags, cups and bottles. The optical studies have shown the significant change in the absorption edge in case of C-dots in comparison to their activated counterparts. The respective variation in the sizes is correlated with the change in electronic band gap values of formed particles. The changes in the luminescence behaviour are also correlated with transitions from the edge of the core of formed particles. The obtained variations in the Stokes shift values of C-dots, and their ACs were used to explore the types of surface states and their related transitions in particles. The mode of interaction between C-dots and their ACs was also determined using solvent-dependent fluorescence spectroscopy. This detailed investigation could provide significant insight on the emission behaviour and the potential usage of formed particles as an effective fluorescent probe in sensing applications.
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- 2023
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31. Highly Efficient Self-Assembled Activated Carbon Cloth-Templated Photocatalyst for NADH Regeneration and Photocatalytic Reduction of 4-Nitro Benzyl Alcohol
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Vaibhav Gupta, Rajesh K. Yadav, Ahmad Umar, Ahmed A. Ibrahim, Satyam Singh, Rehana Shahin, Ravindra K. Shukla, Dhanesh Tiwary, Dilip Kumar Dwivedi, Alok Kumar Singh, Atresh Kumar Singh, and Sotirios Baskoutas
- Subjects
EC-R@ACC photocatalyst ,NADH regeneration ,4-nitro benzyl alcohol ,solar light ,photocatalytic ,Chemical technology ,TP1-1185 ,Chemistry ,QD1-999 - Abstract
This manuscript emphasizes how structural assembling can facilitate the generation of solar chemicals and the synthesis of fine chemicals under solar light, which is a challenging task via a photocatalytic pathway. Solar energy utilization for pollution prevention through the reduction of organic chemicals is one of the most challenging tasks. In this field, a metal-based photocatalyst is an optional technique but has some drawbacks, such as low efficiency, a toxic nature, poor yield of photocatalytic products, and it is expensive. A metal-free activated carbon cloth (ACC)–templated photocatalyst is an alternative path to minimize these drawbacks. Herein, we design the synthesis and development of a metal-free self-assembled eriochrome cyanine R (EC-R) based ACC photocatalyst (EC-R@ACC), which has a higher molar extinction coefficient and an appropriate optical band gap in the visible region. The EC-R@ACC photocatalyst functions in a highly effective manner for the photocatalytic reduction of 4-nitro benzyl alcohol (4-NBA) into 4-amino benzyl alcohol (4-ABA) with a yield of 96% in 12 h. The synthesized EC-R@ACC photocatalyst also regenerates reduced forms of nicotinamide adenine dinucleotide (NADH) cofactor with a yield of 76.9% in 2 h. The calculated turnover number (TON) of the EC-R@ACC photocatalyst for the reduction of 4-nitrobenzyl alcohol is 1.769 × 1019 molecules. The present research sets a new benchmark example in the area of organic transformation and artificial photocatalysis.
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- 2023
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32. A Quasi oppositional smell agent optimization and its levy flight variant: A PV/Wind/battery system optimization application.
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Abdullahi Abubakar Mas'ud, Ahmed T. Salawudeen, Abubakar Ahmad Umar, Ali Saleh Aziz, Yusuf A. Sha'aban, Firdaus Muhammad-Sukki, and Umar Musa
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- 2023
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33. Low-cost and facile synthesis of chromium doped PbI2 nanostructures for optoelectronic devices and radiation detectors: Comparative study
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V. Ganesh, T.H. Al Abdulaal, S.G.S. Al-Amri, H.Y. Zahran, H. Algarni, Ahmad Umar, Hasan B. Albargi, I.S. Yahia, and M.A. Ibrahim
- Subjects
Cr-doped PbI2 nanosheets ,Microwave synthesis ,Radiation ,Optical/dielectric properties ,Materials of engineering and construction. Mechanics of materials ,TA401-492 ,Industrial electrochemistry ,TP250-261 - Abstract
The synthesis of pure and different concentrations of Cr-doped (1, 2.5, 5, 7, 10 wt%) lead iodide (PbI2) nanosheets was successfully achieved using a low-cost and simple microwave method. The prepared Cr-doped PbI2 nanostructures were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), FT-Raman, diffuse reflectance, dielectric, and gamma absorption analysis. The structural investigation confirmed the hexagonal phase of the proposed nanostructures without the impurity phase. Morphological studies proved that the undoped PbI2 nanosheet has a size of less than 100 nm, and the size of the prepared Cr-doped PbI2 samples was around 50-60 nm. FT-Raman and optical analysis investigated the doping effects on the pure PbI2 matrix through the slight shifting of characteristics peaks and the energy bandgaps’ variations. The optical bandgap values of pure PbI2 and Cr-doped PbI2 samples were estimated to be ranged from 2.0 eV to 2.2 eV. The obtained values of the dielectric constant were increased from 20 to 27 due to introducing the Cr- ions into the host PbI2 matrix. Together with Cr- dopants, the linear coefficient of Gamma absorption illustrates improvements. To conclude, due to the enhancement in structural morphology, optical, and radiation properties of the synthesized Cr-doped PbI2 nanostructures, those proposed nanosheets potentially are remarkable candidates for various applications including optoelectronics and radiation detectors.
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- 2022
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34. Ozone Layer Depletion and Emerging Public Health Concerns - An Update on Epidemiological Perspective of the Ambivalent Effects of Ultraviolet Radiation Exposure
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Sheikh Ahmad Umar and Sheikh Abdullah Tasduq
- Subjects
ultraviolet radiation (UV) ,skin photodamage ,ozone layer depletion ,vitamin D deficiency ,sun protection measures ,food fortification ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Solar ultraviolet (UV) radiation exposure is the primary etiological agent responsible for developing cutaneous malignancies. Avoiding excessive radiation exposure, especially by high-risk groups, is recommended to prevent UV-induced photo-pathologies. However, optimal sun exposure is essential for the healthy synthesis of about 90% of vitamin D levels in the body. Insufficient exposure to UV-B is linked to vitamin D deficiency in humans. Therefore, optimal sun exposure is necessary for maintaining a normal state of homeostasis in the skin. Humans worldwide face a major existential threat because of climate change which has already shown its effects in several ways. Over the last 4 to 5 decades, increased incidences in skin cancer cases have led international health organizations to develop strong sun protection measures. However, at the same time, a growing concern about vitamin D deficiency is creating a kind of exposure dilemma. Current knowledge of UV exposure to skin outweighs the adverse effects than the beneficial roles it offers to the body, necessitating a correct public health recommendation on optimal sun exposure. Following an appropriate recommendation on optimal sun exposure will lead to positive outcomes in protecting humans against the adverse effects of strict recommendations on sun protection measures. In this short review, we spotlight the ambivalent health effects of UV exposure and how ozone layer depletion has influenced these effects of UVR. Further, our aim remains to explore how to lead towards a balanced recommendation on sun protection measures to prevent the spurt of diseases due to inadequate exposure to UV-B.
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- 2022
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35. Enhanced In Vivo Wound Healing Efficacy of a Novel Piperine-Containing Bioactive Hydrogel in Excision Wound Rat Model
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Saeed Ali Alsareii, Javed Ahmad, Ahmad Umar, Mohammad Zaki Ahmad, and Ibrahim Ahmed Shaikh
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piperine ,hydrogel ,carbopol 934 ,Aloe vera gel ,wound healing ,excision wound ,Organic chemistry ,QD241-441 - Abstract
These days an extensive amount of the attention of researchers is focused towards exploring bioactive compounds of natural or herbal origin for therapeutic intervention in different ailments of significant importance. One such novel bioactive compound that has a variety of biological properties, including anti-inflammatory and antioxidant activities, is piperine. However, until today, piperine has not been explored for its potential to improve inflammation and enhance healing in acute and chronic wounds. Therefore, the present study aimed to investigate the wound healing potential of piperine hydrogel formulation after topical application. Hydrogels fit the need for a depot system at the wound bed, where they ensure a consistent supply of therapeutic agents enclosed in their cross-linked network matrices. In the present study, piperine-containing carbopol 934 hydrogels mixed with Aloe vera gels of different gel strengths were prepared and characterized for rheological behavior, spreadability, extrudability, and percent (%) content uniformity. Furthermore, the wound healing potential of the developed formulation system was explored utilizing the excision wound healing model. The results of an in vivo study and histopathological examination revealed early and intrinsic healing of wounds with the piperine-containing bioactive hydrogel system compared to the bioactive hydrogel system without piperine. Therefore, the study’s findings establish that the piperine-containing bioactive hydrogel system is a promising therapeutic approach for wound healing application that should be diligently considered for clinical transferability.
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- 2023
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36. Highly Selective Nitrogen-Doped Graphene Quantum Dots/Eriochrome Cyanine Composite Photocatalyst for NADH Regeneration and Coupling of Benzylamine in Aerobic Condition under Solar Light
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Ruchi Singh, Rajesh K. Yadav, Ravindra K. Shukla, Satyam Singh, Atul P. Singh, Dilip K. Dwivedi, Ahmad Umar, and Navneet K. Gupta
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NADH regeneration ,NGQDs@EC composite ,Glucose ,Graphene ,Chemical technology ,TP1-1185 ,Chemistry ,QD1-999 - Abstract
Photocatalysis is an ecofriendly and sustainable pathway for utilizing solar energy to convert organic molecules. In this context, using solar light responsive graphene-based materials for C–N bond activation and coenzyme regeneration (nicotinamide adenine dinucleotide hydrogen; NADH) is one of the utmost important and challenging tasks in this century. Herein, we report the synthesis of nitrogen-doped graphene quantum dots (NGQDs)-eriochrome cyanine (EC) solar light active highly efficient “NGQDs@EC” composite photocatalyst for the conversion of 4-chloro benzylamine into 4-chloro benzylamine, accompanied by the regeneration of NADH from NAD+, respectively. The NGQDs@EC composite photocatalyst system is utilized in a highly efficient and stereospecific solar light responsive manner, leading to the conversion of imine (98.5%) and NADH regeneration (55%) in comparison to NGQDs. The present research work highlights the improvements in the use of NGQDs@EC composite photocatalyst for stereospecific NADH regeneration and conversion of imine under solar light.
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- 2023
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37. Label-Free Myoglobin Biosensor Based on Pure and Copper-Doped Titanium Dioxide Nanomaterials
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Ahmad Umar, Mazharul Haque, Shafeeque G. Ansari, Hyung-Kee Seo, Ahmed A. Ibrahim, Mohsen A. M. Alhamami, Hassan Algadi, and Zubaida A. Ansari
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Cu-doped TiO2 ,myoglobin ,acute myocardial infarction ,electrochemical biosensor ,Biotechnology ,TP248.13-248.65 - Abstract
In this study, using pure and copper-doped titanium dioxide (Cu-TiO2) nanostructures as the base matrix, enzyme-less label free myoglobin detection to identify acute myocardial infarction was performed and presented. The Cu-TiO2 nanomaterials were prepared using facile sol–gel method. In order to comprehend the morphologies, compositions, structural, optical, and electrochemical characteristics, the pure and Cu-TiO2 nanomaterials were investigated by several techniques which clearly revealed good crystallinity and high purity. To fabricate the enzyme-less label free biosensor, thick films of synthesized nanomaterials were applied to the surface of a pre-fabricated gold screen-printed electrode (Au-SPE), which serves as a working electrode to construct the myoglobin (Mb) biosensors. The interference study of the fabricated biosensor was also carried out with human serum albumin (HSA) and cytochrome c (cyt-c). Interestingly, the Cu-doped TiO2 nanomaterial-based Mb biosensor displayed a higher sensitivity of 61.51 µAcm−2/nM and a lower detection limit of 14 pM with a response time of less than 10 ms.
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- 2022
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38. High Power-Conversion Efficiency of Lead-Free Perovskite Solar Cells: A Theoretical Investigation
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Ahmad Umar, Sadanand, Pravin Kumar Singh, D. K. Dwivedi, Hassan Algadi, Ahmed A. Ibrahim, Mohsen A. M. Alhammai, and Sotirios Baskoutas
- Subjects
perovskite ,electron transport layer ,hole transport layer ,SCAPS-1D ,Mechanical engineering and machinery ,TJ1-1570 - Abstract
Solar cells based on lead-free perovskite have demonstrated great potential for next-generation renewable energy. The SCAPS-1D simulation software was used in this study to perform novel device modelling of a lead-free perovskite solar cell of the architecture ITO/WS2/CH3NH3SnI3/P3HT/Au. For the performance evaluation, an optimization process of the different parameters such as thickness, bandgap, doping concentration, etc., was conducted. Extensive optimization of the thickness and doping density of the absorber and electron transport layer resulted in a maximum power-conversion efficiency of 33.46% for our designed solar cell. Because of the short diffusion length and higher defect density in thicker perovskite, an absorber thickness of 1.2 µm is recommended for optimal solar cell performance. Therefore, we expect that our findings will pave the way for the development of lead-free and highly effective perovskite solar cells.
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- 2022
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39. Study on Volumetric, Compressibility and Viscometric Behavior of Cationic Surfactants (CTAB and DTAB) in Aqueous Glycyl Dipeptide: A Thermo-Acoustic Approach
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Santosh Kumari, Suvarcha Chauhan, Kuldeep Singh, Ahmad Umar, Hassan Fouad, and Mohammad Shaheer Akhtar
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glycyl dipeptide ,volumetric ,apparent molar volume ,isentropic compressibility ,dehydration ,Organic chemistry ,QD241-441 - Abstract
This study aims to understand how glycyl dipeptide affected the compressibility, volumetric behavior and viscometric behavior of the cationic surfactants CTAB (Cetyltrimethylammonium bromide) and DTAB (dodecyltrimethylammonium bromide). Information on solute–solute, solute–solvent, and solvent–solvent interactions has been inferred using the quantification of density (ρ), speed of sound (u) and viscosity in aqueous media containing glycyl dipeptide in the temperature range 293.15–313.15 K at an interval of 5 K. The data from the aforementioned research have been used to enumerate numerous volumetric and compressibility metrics that aid in the collection of information about the interactional behavior of the system under consideration. The study suggests that CTAB interacts strongly compared to DTAB with dipeptide, and it also significantly dehydrates glycyl dipeptide. The difference in water–water interactions caused by the loss of hydrophobic hydration of the surfactant molecules upon the addition of cationic surfactants may be the cause of the variation in determined parameters with surfactant concentration. Consideration of the structural rearrangement of molecules that may occur in the system has been used to explain the results of viscosity and computed factors related to viscosity. The patterns of competitive intermolecular interactions in the ternary (dipeptide + water + surfactant) system have been used to analyze the trends of all the parameters. The study may be helpful to understand the stability and structural changes in protein–surfactant systems mediated through various interactions that may be present in the system.
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- 2022
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40. Volumetric, Compressibility and Viscometric Approach to Study the Interactional Behaviour of Sodium Cholate and Sodium Deoxycholate in Aqueous Glycyl Glycine
- Author
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Santosh Kumari, Suvarcha Chauhan, Kuldeep Singh, Ahmad Umar, Hassan Fouad, Mohammed S. Alissawi, and Mohammad Shaheer Akhtar
- Subjects
intermolecular interactions ,glycyl glycine ,bio-surfactants ,apparent molar volume ,isentropic compressibility ,apparent molar adiabatic compression ,Organic chemistry ,QD241-441 - Abstract
Viscosity, speed of sound (u), and density (ρ) have been measured in aqueous glycyl glycine solution over a temperature range from 293.15 to 313.15 K with a 5 K interlude to evaluate the volumetric and compressibility properties of bio-surfactants, namely sodium cholate (NaC; 1–20 mmol∙kg−1) and sodium deoxycholate (NaDC; 1–10 mmol∙kg−1). Density and viscosity findings provide information on both solute–solute and solute–solvent types of interactions. Many other metrics, such as apparent molar adiabatic compression (κS,φ), isentropic compressibility (κS), and apparent molar volume (Vφ), have been calculated from speed of sound and density measurements, utilising experimental data. The results show that the zwitterionic end group in the glycyl glycine strongly interacts with NaDC and NaC, promoting its micellization. Since the addition of glycyl glycine causes the bio-surfactant molecules to lose their hydrophobic hydration, the observed concentration-dependent changes in apparent molar volume and apparent molar adiabatic compression are likely attributable to changes in water–water interactions. Viscous relaxation time (τ) increases significantly with a rise in bio-surfactant concentration and decreases with increasing temperature, which may be because of structural relaxation processes resulting from molecular rearrangement. All of the estimated parameters have been analysed for their trends with regard to the different patterns of intermolecular interaction present in an aqueous glycyl glycine solution and bio-surfactant system.
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- 2022
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41. Novel Hydrophobic Polyvinyl-Alcohol Formaldehyde Sponges: Synthesis, Characterization, Fast and Effective Organic Solvent Uptake from Contaminated Soil Samples
- Author
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Yajvinder Saharan, Joginder Singh, Rohit Goyat, Ahmad Umar, and Sheikh Akbar
- Subjects
hydrophobic ,sponges ,contaminated soil/water system ,Organic chemistry ,QD241-441 - Abstract
In the present research work, PVFTX-100, PVFSDS, and PVFT-80 sponges were prepared using polyvinyl-alcohol (PVA) with surfactants triton X-100/sodium dodecyl sulfate (SDS)/Tween 80, respectively, for the removal of organic solvents from polluted soil/water samples. All three obtained sponges were further made hydrophobic using dodecyltrimethoxysilane (DTMS). The prepared sponges were characterized using different spectroscopic techniques and SEM analysis. The peaks obtained near 1050 cm−1 and 790 cm−1 were attributed to Si-O-C and alkyl side chain C-H stretching vibration that confirmed the formation of desired sponges. The SEM images showed the random roughness with a number of protrusions on sponge surfaces, which further played an important role in the absorption and retention of organic solvents molecules. The Sears method was chosen to calculate the surface area and pore volume of all the synthesized sponge samples. Among all three prepared sponges, the PVFTX-100 sponge showed a high pore volume and large surface area, with a maximum percentage absorption capacity of 96%, 91%, 89.9%, 85.6%, and 80 for chlorobenzene, toluene, diesel, petrol, and hexane, respectively, after eightcycles. The organic solvent uptake using PVFTX-100, PVFSDS, and PVFT-80 sponges is quite a unique and simple technology, which could be employed at a large scale for contaminated soil/water systems.
- Published
- 2022
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42. Farnesol Protects against Cardiotoxicity Caused by Doxorubicin-Induced Stress, Inflammation, and Cell Death: An In Vivo Study in Wistar Rats
- Author
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Abdulrab Ahmed M. Alkhanjaf, Md Tanwir Athar, Zabih Ullah, Abdullah Mohammed H. Alsayhab, Ahmad Umar, and Ibrahim Ahmed Shaikh
- Subjects
farnesol ,reactive oxygen species ,caspase-3 ,NF-kB ,inflammation ,cardioprotection ,Organic chemistry ,QD241-441 - Abstract
Doxorubicin (DOXO) is an antineoplastic drug that is used extensively in managing multiple cancer types. However, DOXO-induced cardiotoxicity is a limiting factor for its widespread use and considerably affects patients’ quality of life. Farnesol (FSN) is a sesquiterpene with antioxidant, anti-inflammatory, and anti-tumor properties. Thus, the current study explored the cardioprotective effect of FSN against DOXO-induced cardiotoxicity. In this study, male Wistar rats were randomly divided into five groups (n = 7) and treated for 14 days. Group I (Control): normal saline, p.o. daily for 14 days; Group II (TOXIC): DOXO 2.4 mg/kg, i.p, thrice weekly for 14 days; Group III: FSN 100 mg/kg, p.o. daily for 14 days + DOXO similar to Group II; Group IV: FSN 200 mg/kg, p.o. daily for 14 days + DOXO similar to Group II; Group V (Standard): nifedipine 10 mg/kg, p.o. daily for 14 days + DOXO similar to Group II. At the end of the study, animals were weighed, blood was collected, and heart-weight was measured. The cardiac tissue was used to estimate biochemical markers and for histopathological studies. The observed results revealed that the FSN-treated group rats showed decrease in heart weight and heart weight/body weight ratio, reversed the oxidative stress, cardiac-specific injury markers, proinflammatory and proapoptotic markers and histopathological aberrations towards normal, and showed cardioprotection. In summary, the FSN reduces cardiac injuries caused by DOXO via its antioxidant, anti-inflammatory, and anti-apoptotic potential. However, more detailed mechanism-based studies are needed to bring this drug into clinical use.
- Published
- 2022
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43. Influence of Nanomaterials and Other Factors on Biohydrogen Production Rates in Microbial Electrolysis Cells—A Review
- Author
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Nabil. K. Abd-Elrahman, Nuha Al-Harbi, Yas Al-Hadeethi, Adel Bandar Alruqi, Hiba Mohammed, Ahmad Umar, and Sheikh Akbar
- Subjects
Microbial Electrolysis Cells (MECs) ,bio-hydrogen production rates (Bio-HPR) ,nanomaterials ,columbic efficiency (CE) ,cathode bio-hydrogen recovery (C Bio-HR) ,Organic chemistry ,QD241-441 - Abstract
Microbial Electrolysis Cells (MECs) are one of the bioreactors that have been used to produce bio-hydrogen by biological methods. The objective of this comprehensive review is to study the effects of MEC configuration (single-chamber and double-chamber), electrode materials (anode and cathode), substrates (sodium acetate, glucose, glycerol, domestic wastewater and industrial wastewater), pH, temperature, applied voltage and nanomaterials at maximum bio-hydrogen production rates (Bio-HPR). The obtained results were summarized based on the use of nanomaterials as electrodes, substrates, pH, temperature, applied voltage, Bio-HPR, columbic efficiency (CE) and cathode bio-hydrogen recovery (C Bio-HR). At the end of this review, future challenges for improving bio-hydrogen production in the MEC are also discussed.
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- 2022
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44. Government Effectiveness and Socio-Economic Equity: An Empirical Analysis of Sustainable Social Protection Systems in Developing Countries Using Two-Step System GMM Econometric Approach.
- Author
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Ahmad, Umar Suffian, Fakher, Muhammad Amjad, and Arif, Muhammad
- Subjects
ECONOMETRICS ,SUSTAINABILITY ,CAPACITY building ,EMPIRICAL research ,DEVELOPING countries - Abstract
This paper aims to study the nexus between government effectiveness and socioeconomic equity, which leads to a sustainable social protection system. We have empirically investigated the nexus through a panel data set of 46 developing countries for a period of 20 years. Developing countries face socio-economic inequity due to ineffective government policies leads to the collapse of the social protection system. We have developed an index of sustainable protection systems using the Keyser Meyer Olkin Methodology used as a sampling adequacy. We found a positive association between government effectiveness and social protection systems in developing countries. However, a weak mechanism may cause the poor implementation of sustainable social protection needs utmost policy maneuvers in those countries. There is a need for capacity building of government institutions to improve their effectiveness. Action should be taken that promotes transparency, accountability, and good governance practices. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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- View/download PDF
45. Haemato-biochemical Response to Kirschner Pin and Improvised Chrome Vanadium Long Screw Used for the Stabilization of Femoral Fracture in Goats.
- Author
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Salisu, Ahmad Umar, Abdul, Abubakar Adamu, Salisu, Buhari, Salisu, Abubakar Muhammad, Sadiq, Yakubu Abubakar, and Charles, Mshelia Peter
- Subjects
GOATS ,ORTHOPEDIC implants ,INTERNAL fixation in fractures ,BLOOD sampling ,HEMATOLOGY ,ALANINE aminotransferase - Abstract
The stainless-steel orthopaedic implants used for the management of various types of fracture internal fixations are very expensive; this makes their utilization in food animals relatively noneconomical. There is a need to have an improvised implant that is cheaper and available for use in food animals to manage complicated fractures requiring open reduction and internal fixation. The objective of this study is to evaluate the haematological and biochemical changes following the reduction of stable femoral fractures in goats using conventional (Kirschner pin) and improvised chrome vanadium-coated long crews. Twelve apparently healthy Red Sokoto bucks were randomly divided into two groups of six (n=6) were used for this study. A transverse femoral diaphyseal fracture was created using orthopaedic wire in both groups. In group A, a conventional Kirschner pin size 4.0x125 mm2, single trocar, non-threaded, was used to immobilize the fracture, while in group B, an improvised test chrome vanadium (long screw) size 2.3 mm was used for the fracture immobilizations. Blood samples were collected before fracture induction at the base line, serving as a control. The haematological and biochemical assessments were performed at 0 weeks (immediate postoperative) and subsequently at 2, 4, 6, 8, 10 and 12 weeks postoperatively. Packed cell volume (PCV%), haemoglobin concentration (Hb), red blood cell count (RBCs), white blood cell count (WBCs) and differential leukocytic count (neutrophils, lymphocytes and monocytes) were evaluated. Also, serum activity of alkaline phosphatase (ALP), alanine aminotransferase (ALT), and aspartate aminotransferase (AST) was detected. Besides, serum calcium, phosphorous and creatinine levels were evaluated. There were no significant differences between the two groups in PCV, haemoglobin, RBCs, WBCs and neutrophils, and the values were within the normal range. However, lymphocytes and monocytes were significantly (p<0.05) different at weeks 2 and 6, respectively. Biochemical parameters revealed significant (p<0.05) changes in serum ALT (weeks 0, 2, 4), ALP (week 6), creatinine (weeks 10 and 12), and calcium (week 2) at some postoperative intervals. However, no variations were observed in serum AST and phosphorous, which were within the normal range. The improvised chrome vanadium (Long screw) can be used safely in goats for the management of stable femoral fractures without significant adverse changes to hemato-biochemical profiles within twelve weeks. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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- View/download PDF
46. Computation-Efficient Distributed Algorithm for Convex Optimization Over Time-Varying Networks With Limited Bandwidth Communication.
- Author
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Huaqing Li 0001, Chicheng Huang, Zheng Wang 0043, Guo Chen 0002, and Hafiz Gulfam Ahmad Umar
- Published
- 2020
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- View/download PDF
47. Bifunctional CoP electrocatalysts for overall water splitting
- Author
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Zhongxin Duan, Hengqi Liu, Xiaojie Tan, Ahmad Umar, and Xiang Wu
- Subjects
Overall water splitting ,CoP, hydrogen evolution reaction ,Oxygen evolution reaction ,Alkaline media ,Chemistry ,QD1-999 - Abstract
Overall water splitting becomes an important strategy for the generation of hydrogen and oxygen in today's needs of green energy. Therefore, it is important to develop bifunctional electrocatalysts with cheap and high-efficient characteristics. However, traditional bifunctional catalysts usually exhibit high overpotential and poor stability during both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Herein, we synthesized several kinds of CoP nanorod catalysts through a facile hydrothermal method and subsequent thermal phosphorization process. The as-obtained CoP-1.5 product showed an overpotential of 58 mV for HER at 10 mA cm−2 and 284 mV for OER at 50 mV cm−2 in 1 M KOH. Moreover, the bifunctional catalyst, delivered a cell voltage of 1.66 V at 50 mA cm−2.
- Published
- 2022
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- View/download PDF
48. Fabrication and characterization of high-performance photodetectors based on Au/CdS/Au and Au/Ni:CdS/Au junctions
- Author
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Hasan Albargi, Z.R. Khan, R. Marnadu, H.Y. Ammar, Hassan Algadi, Ahmad Umar, I.M. Ashraf, and Mohd. Shkir
- Subjects
Ni:CdS thin films ,Structural properties ,Optical properties ,Nonlinear optics ,Au CdS Au ,Au Ni:CdS ,Science (General) ,Q1-390 - Abstract
The synthesis, characterization, and photodetector application of pure and Ni doped CdS thin films prepared by the spray pyrolysis technique are presented in this paper. Various techniques were used to analyze the thin films that had been produced. The hexagonal phase of the produced thin films is confirmed by X-ray diffraction (XRD) and FT-Raman (FTR) measurements. Scanning electron microscopy (SEM) was used to investigate the morphology of the thin film surface, revealing the development of nanograins. The energy band gaps for all of the prepared thin films were calculated to be approximately 2.4 eV. When the films were stimulated at 450 nm wavelength, a strong photoluminescence emission was seen at ∼540 ± 6 nm. The dark/photo I-V electrical performance of the developed films was observed. The fabricated Au/CdS/Au and Au/Ni:CdS/Au photodetectors were studied for recombination behavior, dark and photo surface resistivity, and photosensitivity. Interestingly, the dark surface resistivity was found to be greater compared to the photo-resistivity. When the light intensity was increased to 1450 Lux, the photosensitivity improves from 10% to 35%. These findings indicate that the fabricated CdS/Ni:CdS films-based photodetectors are suitable for optoelectronic devices.
- Published
- 2021
- Full Text
- View/download PDF
49. Correlation between Nasal Foreign Bodies and Their Presentation in Paediatric Age Group
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Mumtaz Ahmad Umar, Mohibullah Mushwani, Ayesha Jawad, and Naveed Arshad
- Subjects
Age groups ,Foreign bodies ,Nasal obstruction ,Pediatrics ,Medicine - Abstract
Objectives: To observe the relationship of nasal foreign bodies in terms of patient’s age as well as the type of foreign body and removal technique. Materials and Methods: This retrospective cross-sectional study was conducted in ENT department, Akbar Niazi Teaching Hospital, Islamabad from April 2017 to May 2018. A total of 120 patients selected by non-probability consecutive sampling technique with inclusion criteria of all children less than 12 years with foreign body in nose were recruited for this study after taking written informed consent. Patients who had concurrent nasal infections and trauma were excluded. Children age, gender, site, type of foreign body and removal technique were recorded. Data was analyzed by using SPSS version 21. Results: A total of 120 patients were presented with nasal foreign bodies, 107 cases were successfully dealt with in OPD while 13 patients were admitted for removal under general anaesthesia. The commonest affected age group was 2-5 years (78.33%) with more females (55.75%) than males (44.25%). Organic type of foreign body was 55.8% and inorganic type of foreign body was 44.2%. Seeds and small nuts (35%) were found to be the commonest types of nasal foreign body. The correlation between age groups, types of foreign body, removal technique and site of foreign body was significant (p value ≤ 0.05). Conclusion: Nasal foreign bodies are commonly faced problem in children, specially in 2-5 years of age. They are largely harmless but complications can occur if neglected. Prevention remains the best option while for non-cooperative and attempted cases, removal under general anaesthesia is safe and preferred.
- Published
- 2021
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- View/download PDF
50. Recent advances in nano-photocatalysts for organic synthesis
- Author
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N.P. Radhika, Rosilda Selvin, Rita Kakkar, and Ahmad Umar
- Subjects
Chemistry ,QD1-999 - Abstract
This review seeks to explore the literature pertaining to the applicability of nano-photocatalysts in fine chemical synthesis of organic compounds. The current methods of preparation of organic compounds in laboratories and industries are highly demanding on the non-renewable sources of energy. These conventional methods also generally require extreme conditions of temperature and pressure. Owing to deeper global awareness toward conservation of non-renewable sources of energy, there has been a shift of focus toward photocatalysis in the recent years. Photocatalysts are long known to catalyze various organic reactions such as oxidation, reduction, addition, cyclization and decomposition. The advent of nanotechnology made it possible to scale down these photocatalytic materials from bulk- to nano-scale and thereby further widen their scope and efficiency. Advances in material chemistry and nanotechnology have also made it possible to synthesize nanophotocatalysts of new genres, properties of which can be controlled and designed at molecular level. In this review, an attempt has been made to classify these diverse nanophotocatalysts into different groups, based on their composition and mechanism. Since the literature survey revealed that the chemoselectivity and efficiency of the nanophotocatalysts depend on their method of preparation, an overview of their common synthesis protocols is included. The review also highlights the various organic conversions for which these nanomaterials can be used under UV/visible irradiation. Nanophotocatalysts hold a great promise for environmentally-benign synthesis of highly useful organic compounds. We believe that this review can provide insights into research done in this field so far, which can pave way for further progress in this topic of far-fetched social significance. Keywords: Photocatalysis, Nano-photocatalysis, Organic synthesis, Green Chemistry, Photosensitization
- Published
- 2019
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