| 1. |
- Qureshi, Tayyab, et al.
(författare)
-
Structural and thermal investigation of lignocellulosic biomass conversion for enhancing sustainable imperative in progressive organic refinery paradigm for waste-to-energy applications
- 2024
-
Ingår i: Environmental Research. - : Elsevier. - 0013-9351 .- 1096-0953. ; 246
-
Tidskriftsartikel (refereegranskat)abstract
- The depletion of finite fossil fuel reserves and the severe environmental degradation resulting from human activities have compelled the expeditious development and application of sustainable waste to energy technologies. To encapsulate energy and environment in sustainability paradigm, bio waste based energy production is need to be forged in organic bio refinery setup. According to world bioenergy association, biomass can cover 50 % of the primary energy demand of the world. Therefore, the present study focuses on reforming the energy mix for a clean energy generation, where, sample composition of cotton stalk was acidified in dilute (5% wt.) hydrochloric acid (HCL) for analyzing material burnout patterns in biomass conversion systems utilized in organic bio refinery sector. Advanced thermochemical burning technique, which includes pyrolysis and combustion was applied at four different leaching times from 0 to 180 min under nitrogen environment from 0 degrees C to 500 degrees C and air from 500 degrees C to 900 degrees C, respectively. Different analyses including proximate, ultimate, gross calorific value (GCV), thermos-gravimetric, kinetic, XRD, FTIR, SEM-EDS were used for analyzing the degradation of demineralized cotton stalk at different treatment rates. Proximate study demonstrated that cotton stalk leaching for 180 min has efficiently infused HCL, leading in a significant increase in fixed carbon and higher heating value of 20.23 % and 12.48%, respectively, as well as a reduction in carbon footprint of around 54.80%. The findings of proximate was validated by GCV analysis and CHNS analysis as value of carbon and hydrogen has shown increasing behavior with the time delay in demineralization Thermo-gravimetric and derivative thermo-gravimetric data analyses shows an increasing trend of conversion efficiency, with the maximum increase of 98 % reported for sample 3H. TT.DEM. XRD characterization has reported 23 degrees to 25 degrees angle for all the observed peaks. Sample 3H.TT.DEM has shown maximum angle inclination along with matured crystalline peak. The latter observations has been validated by FTIR spectroscopy as sample 3H.TT.DEM has reported maximum O-H group formation. Sample 3H.TT. DEM has reported lowest activation energy of 139.51 kJ*mole-1 and lowest reactivity of 0.000293649%*min 0C, due to moderate and stable reactiveness. In SEM examination, increment in pore size and number of pores within the structural matrix of cotton stalk was observed with the enhancement in acidulation process. Furthermore, in EDS analysis, 3H.TT.DEM has shown most balanced distribution of the elements. In this research, sustainable transformation of biomass is envisioned to improve the waste bio refinery system, significantly contributing to the achievement of Sustainable Development Goals 7, 12 and 13.
|
|
| 2. |
- Ahsan, Hajra, et al.
(författare)
-
Photocatalysis and adsorption kinetics of azo dyes by nanoparticles of nickel oxide and copper oxide and their nanocomposite in an aqueous medium
- 2022
-
Ingår i: PeerJ. - : PeerJ. - 2167-8359. ; 10
-
Tidskriftsartikel (refereegranskat)abstract
- Azo dyes are recalcitrant organic pollutants present in textile industry effluents. Conventional treatment methods to remove them come with a range of disadvantages. Nanoparticles and their nanocomposites offer more efficient, less expensive and easy to handle wastewater treatment alternative. Methods. In this study, nanoparticles of nickel oxide (NiO-NPs), copper oxide (CuO-NPs) and their nanocomposite (NiO/CuO-NC) were synthesized using co- precipitation method. The functional groups present on the surface of synthesized nanomaterials were verified using Fourier-transform infrared spectroscopy (FTIR). Surface morphology was assessed using scanning electron microscopy (SEM) whereas purity, shape and size of the crystallite were determined using X-ray diffraction (XRD) technique. The potential of these nanomaterials to degrade three dyes i.e., Reactive Red-2 (RR-2), Reactive Black-5 (RB-5) and Orange II sodium salt (OII) azo dyes, was determined in an aqueous medium under visible light (photocatalysis). The photodegradation effectiveness of all nanomaterials was evaluated under different factors like nanomaterial dose (0.02-0.1 g 10 mL-1), concentration of dyes (20-100 mg L-1), and irradiation time (60-120 min). They were also assessed for their potential to adsorb RR-2 and OII dyes. Results. Results revealed that at optimum concentration (60 mgL-1) of RR-2, RB-5, and OII dyes, NiO-NPs degraded 90, 82 and 83%, CuO-NPs degraded 49, 34, and 44%, whereas the nanocomposite NiO/CuO-NC degraded 92, 93, and 96% of the said dyes respectively. The nanomaterials were categorized as the efficient degraders of the dyes in the order: NiO/CuO-NC > NiO-NPs > CuO-NPs. The highest degradation potential shown by the nanocomposite was attributed to its large surface area, small particles size, and quick reactions which were proved by advance analytical techniques. The equilibrium and kinetic adsorption of RR-2 and OII on NiO-NPs, CuO-NPs, and NiO/CuO-NC were well explained with Langmuir and Pseudo second order model, respectively (R2 ≥0.96). The maximum RR-2 adsorption (103 mg/g) was obtained with NiO/CuO-NC. It is concluded that nanocomposites are more efficient and promising for the dyes degradation from industrial wastewater as compared with dyes adsorption onto individual NPs. Thus, the nanocomposite NiO/CuO-NC can be an excellent candidate for photodegradation as well as the adsorption of the dyes in aqueous media.
|
|
| 3. |
- Asif, Muhammad, et al.
(författare)
-
The Effect of Infrared Laser Irradiation on the Surface Morphology and Electrical Properties of Zinc Metal
- 2023
-
Ingår i: Physchem. - : MDPI AG. - 2673-7167. ; 3:1, s. 22-33
-
Tidskriftsartikel (refereegranskat)abstract
- This study details the irradiation of pure (99.995%) and immaculate metallic Zinc using Nd: YAG laser (1064 nm, 10 mJ, 9–14 ns). The influence and impact of multiple laser shots on the formation of microstructures and crystal structure orientations is assessed. Arrays of ablated craters are machined on the whole surface of the target to probe the electrical and topographical characteristics of laser-treated surfaces. Irradiated samples are examined by multiple characterizing techniques such as scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray diffraction (XRD), and a four-point probe for electrical conductivity measurements. SEM and AFM analysis exhibited the formation of laser-induced ripple structures with periodicity sheerly dependent on laser shots. A comparison of surface topography of the virgin and treated samples disclosed a pronounced modification in surface texture. The XRD patterns of laser shined targets indicate no momentous structural change in the crystal structure, whereas the measurements on the electrical conductivity of the irradiated surfaces exhibit an exponential descending trend with an augmentation in laser shots.
|
|
| 4. |
- Mushtaq, Afshan, et al.
(författare)
-
Catalytic oxidative desulfurization of thio-compounds by employing χ-Anderson-type polyoxometalates-porphyrin covalent organic framework (COF)
- 2023
-
Ingår i: Tetrahedron. - : Elsevier. - 0040-4020 .- 1464-5416. ; 144
-
Tidskriftsartikel (refereegranskat)abstract
- Severe environmental sulfur contents due to the consumption of fuels in automobiles and industries resulted in serious health hazards and pollution because of it, desulfurization of diesel become inevitable. Targeting the profound desulfurization of diesel, we performed experiments to deeply desulphurized the thio-compounds by catalytic-oxidative desulfurization technique. We synthesized new metalloporphyrin (C52H36N4O8Sn)4MeO-SnPor which after conversion into (C64H64N8O16Sn)4Tris-SnTP leading towards the synthesis of covalent organic framework [(N(C4H9)4]12[HNC(CH2O)3]4[(CO)4C44H24N4Sn] [NiMo6O18]4(SnTP@NiAdCOF). SnTP@NiAd COF showed the outstanding catalytic property for deep desulfurization of thio-compounds above than 96% of thiobenzoic acid (TB) and 99% of 2-aminothiophenol (2-ATP) sulfur contents were oxides after 100 min of reaction using H2O2 as an oxidant at room temperature with constant stirring. During desulfurization percentage desulfurization efficiency was checked for different time intervals by TLC and further confirmed by reverse phase high-performance liquid chromatography (RP-HPLC). Reverse-phase high-performance liquid chromatograms indicated that the peak area and peak height of thio-compounds decrease gradually with the passage of reaction time which confirmed the removal of thio-compounds from the reaction mixture. Sulfur contents removed up to 5 ppmw showed excellent catalytic characteristics of synthesized SnTP@NiAdCOF. The exceptional catalytic efficiency of prepared catalyst SnTP@NiAdCOF was because of the existence of active oxidizing centers of χ-NiAd and metalloporphyrin that are MoO and [(Por)SnII], respectively. The potential mechanism appeared to be the formation of Mo(O2) and [(Por)SnII–OOH] from MoO and [(Por)SnII], respectively that act as active oxidizing centers and efficiently converted the thio-group into oxides and sulfones. Effective removal of sulfur grants the desulfurization of fuels by using SnTP@NiAdCOF catalyst to lessen the energy expenditure and also to enhance the production of environmentally-safe fuels.
|
|
| 5. |
- Ullah, Hameed, et al.
(författare)
-
Polyoxometalate based ionic liquids reinforced on magnetic nanoparticles: A sustainable solution for microplastics and heavy metal ions elimination from water
- 2024
-
Ingår i: Microchemical journal (Print). - : Elsevier. - 0026-265X .- 1095-9149. ; 204
-
Tidskriftsartikel (refereegranskat)abstract
- To purify water from contaminents is essential for life on universe. Here, in this manuscript we introduces an innovative approach to overcome the intricate challenge of eliminating heavy metal ions and microplastics from water. We designed a mesoporous composite materials by synergistically integrating polyoxometalates (POMs) based ionic liquids with silica coated magnetic nanoparticles. The synthesis process initiates with the utilization of highly reduced molybdenum aggregates in polyoxometalate-ionic liquids, reinforced onto magnetic nanoparticles (POM–IL–MNPs). Crafted composites, including Q8[Mo64Ni8La6]@SiO2@Fe3O4, Q10[Mo64Ni8La6]@SiO2@Fe3O4, Q8[Mo176/Mo248]@SiO2@Fe3O4, and Q10[Mo176/Mo248]@SiO2@Fe3O4, are meticulously designed by substituting POM counter cations with long-chain alkyl-based quaternary ammonium salts. The ionic liquids and composites exhibit remarkable hydrophobicity and thermal stability due to large anions and long-chain organic counter cations. Comprehensive characterization, including FT–IR, UV–vis spectroscopy, TGA, DSC, CV, rheological study, elemental analysis, and ICP-AES, ensures a thorough investigation. Additional analyses, such as Powder X-ray diffraction (PXRD), SEM, EDX, DLS, N2 adsorption, and VSM, reveal amorphous crystallinity, distinctive surface morphology, and substantial specific surface area. Core shell structure of POM-IL-MNPs was determined by Transmision electron microscope (TEM), ICP-AES analysis demonstrates metal ion removal efficiencies from 87.35% to 99.98%, with DLS confirming 100% efficiency in PVC beads elimination. This research not only advances water decontamination but also provides valuable insights into designing and characterizing novel materials with promising environmental applications.
|
|
| 6. |
- Zaman, Muhammad, et al.
(författare)
-
Application of Nanoprecipitation Technique to Develop Poloxamer-407 Facilitated Solid Lipid Nanoparticles for the Controlled Delivery of Tacrolimus
- 2023
-
Ingår i: International Journal of Polymer Science. - : HINDAWI LTD. - 1687-9422 .- 1687-9430. ; 2023
-
Tidskriftsartikel (refereegranskat)abstract
- Currently, the solid lipid nanoparticles (SLNs) are utilized as a novel approach for the controlled drug delivery system (CDDS). Tacrolimus (TCM), a lipophilic drug, can easily be encapsulated in the hydrophobic core of these SLNs using nanoprecipitation technique. The current aim was to develop the controlled release Poloxamer (PLX) facilitated TCM loaded SLNs (PLX/TCM-SLNs), followed by their physicochemical evaluations, including chemical compatibility, particle size, surface charge, surface morphology, nature of SLNs, loading efficiency (LE), entrapment efficiency (EE), in vitro drug release studies, release kinetic modeling, and statistical evaluation. Here we also evaluate physicochemical properties of TCM and investigate solubility profile for improvement and dissolution rate of PLX/TCM-SLNs. PLX was used in the process as a polymer due to its low toxicity and weak immunogenic properties. The prepared formulation was characterized by scanning electron microscopy (SEM) images, and Fourier transform infrared spectroscopy (FTIR) has confirmed the compatibility of the selected ingredients, whereas particle size analysis showed that prepared PLX/TCM-SLNs were of nanosized (120:6 +/- 9nm) having zeta potential of - 21.3 Mv. On the other hand, SEM had revealed the smooth and uniform surface of the particle, while X-ray diffraction (XRD) confirmed the uniform surface as crystalline structure of TCM in PLX/TCM-SLNs masked. A satisfactory level of EE (94:5 +/- 2:74%) has also been noticed. Furthermore, in vitro drug release studies have explored the controlled release of drug during 8 hours, following zero order release kinetics and diffusion type of release mechanism. Outcomes of the studies have advocated the successful preparation of SLNs, as controlled release PLX/TCM-SLNs have been prepared efficiently.
|
|
| 7. |
- Zaman, Muhammad, et al.
(författare)
-
Fabrication of PEGylated Chitosan Nanoparticles Containing Tenofovir Alafenamide : Synthesis and Characterization
- 2022
-
Ingår i: Molecules. - : MDPI. - 1431-5157 .- 1420-3049. ; 27:23
-
Tidskriftsartikel (refereegranskat)abstract
- Tenofovir alafenamide (TAF) is an antiretroviral (ARV) drug that is used for the management and prevention of human immunodeficiency virus (HIV). The clinical availability of ARV delivery systems that provide long-lasting protection against HIV transmission is lacking. There is a dire need to formulate nanocarrier systems that can help in revolutionizing the way to fight against HIV/AIDS. Here, we aimed to synthesize a polymer using chitosan and polyethylene glycol (PEG) by the PEGylation of chitosan at the hydroxyl group. After successful modification and confirmation by FTIR, XRD, and SEM, TAF-loaded PEGylated chitosan nanoparticles were prepared and analyzed for their particle size, zeta potential, morphology, crystallinity, chemical interactions, entrapment efficacy, drug loading, in vitro drug release, and release kinetic modeling. The fabricated nanoparticles were found to be in a nanosized range (219.6 nm), with similar to 90% entrapment efficacy, similar to 14% drug loading, and a spherical uniform distribution. The FTIR analysis confirmed the successful synthesis of PEGylated chitosan and nanoparticles. The in vitro analysis showed similar to 60% of the drug was released from the PEGylated polymeric reservoir system within 48 h at pH 7.4. The drug release kinetics were depicted by the Korsmeyer-Peppas release model with thermodynamically nonspontaneous drug release. Conclusively, PEGylated chitosan has the potential to deliver TAF from a nanocarrier system, and in the future, cytotoxicity and in vivo studies can be performed to further authenticate the synthesized polymer.
|
|
| 8. |
-
- 2019
-
Tidskriftsartikel (refereegranskat)
|
|
| 9. |
- Ahmed, Soban, et al.
(författare)
-
Development and Optimization of Deep Learning Models for Weapon Detection in Surveillance Videos
- 2022
-
Ingår i: Applied Sciences. - : MDPI. - 2076-3417. ; 12:12
-
Tidskriftsartikel (refereegranskat)abstract
- Featured Application This work has applied computer vision and deep learning technology to develop a real-time weapon detector system and tested it on different computing devices for large-scale deployment. Weapon detection in CCTV camera surveillance videos is a challenging task and its importance is increasing because of the availability and easy access of weapons in the market. This becomes a big problem when weapons go into the wrong hands and are often misused. Advances in computer vision and object detection are enabling us to detect weapons in live videos without human intervention and, in turn, intelligent decisions can be made to protect people from dangerous situations. In this article, we have developed and presented an improved real-time weapon detection system that shows a higher mean average precision (mAP) score and better inference time performance compared to the previously proposed approaches in the literature. Using a custom weapons dataset, we implemented a state-of-the-art Scaled-YOLOv4 model that resulted in a 92.1 mAP score and frames per second (FPS) of 85.7 on a high-performance GPU (RTX 2080TI). Furthermore, to achieve the benefits of lower latency, higher throughput, and improved privacy, we optimized our model for implementation on a popular edge-computing device (Jetson Nano GPU) with the TensorRT network optimizer. We have also performed a comparative analysis of the previous weapon detector with our presented model using different CPU and GPU machines that fulfill the purpose of this work, making the selection of model and computing device easier for the users for deployment in a real-time scenario. The analysis shows that our presented models result in improved mAP scores on high-performance GPUs (such as RTX 2080TI), as well as on low-cost edge computing GPUs (such as Jetson Nano) for weapon detection in live CCTV camera surveillance videos.
|
|
| 10. |
- Azeem, Muhammad, et al.
(författare)
-
Chemical composition and repellent activity of native plants essential against dengue mosquito, Aedes aegypti
- 2019
-
Ingår i: Industrial crops and products (Print). - : Elsevier BV. - 0926-6690 .- 1872-633X. ; 140
-
Tidskriftsartikel (refereegranskat)abstract
- Aedes aegypti L. (Diptera: Culicidae) mosquito is an important vector of chikungunya, dengue and yellow fever. Plant based essential oils may serve as good alternatives to commercially available mosquito repellent, DEET. Steam distillation was used for the extraction of essential oils from fresh collected aerial parts of plants viz Chenopodium ambrosioides, Conyza sumatrensis, Erigeron canadensis, Eucalyptus camaldulensis, Mentha spicata, Parthenium hysterophorus, and Tagetes minuta. The essential oils were tested for mosquito repellent activity against laboratory reared female Ae. aegypti by human bait technique. Identification of chemical constituents of essential oils was carried out by gas chromatography-mass spectrometry (GC-MS). The essential oil of M. spicata, E. canadensis, P. hysterophorus, C. sumatrensis, T. minuta, C. ambrosioides, and E. camaldulensis exhibited 100%, 80%, 63.9%, 51.4%, 50.2%, 39.7%, and 13.7% mosquito repellent activity respectively, at the tested dose of 30 mu g/cm(2). The most abundant constituents of M. spicata, E. canadensis, P. hysterophorus, C. sumatrensis and T. minuta essential oils were piperitenone oxide (47.1%), limonene (41.3%), germacrene D (36.6%), cis-lachnophyllum ester (33.3%) and dihydrotagetone (20.9%) respectively. M. spicata essential oil completely inhibited the attractiveness of human hands toward female mosquitoes for more than 45 min thus showed bioactivity comparable to that of commercially used mosquito repellent, DEET. This study suggests that the dilute solution of M. spicata essential oil could be used as potent mosquito repellent against Ae. aegypti alternative to commercially available synthetic mosquito repellents.
|
|
