Displaying publications 1 - 20 of 671 in total

Abstract:
Sort:
  1. Fulltext Nanotechnology for controlling mango malformation: a promising approach
    Shahbaz M, Seelan JSS, Abasi F, Fatima N, Mehak A, Raza MU, et al.
    J Biomol Struct Dyn, 2025 Mar;43(5):2610-2630.
    PMID: 38344816 DOI: 10.1080/07391102.2024.2312449
    Mango (Mangifera indica L.) is one of the most important fruit crops in the world with yields of approximately 40 million tons annually and its production continues to decrease every year as a result of the attack of certain pathogens i.e. Colletotrichum gloeosporioides, Erythricium salmonicolor, Amritodus atkinsoni, Idioscopus clypealis, Idioscopus nitidulus, Bactrocera obliqua, Bactrocera frauenfeldi, Xanthomonas campestris, and Fusarium mangiferae. So F. mangiferae is the most harmful pathogen that causes mango malformation disease in mango which decreases its 90% yield. Nanotechnology is an eco-friendly and has a promising effect over traditional methods to cure fungal diseases. Different nanoparticles possess antifungal potential in terms of controlling the fungal diseases in plants but applications of nanotechnology in plant disease managements is minimal. The main focus of this review is to highlight the previous and current strategies to control mango malformation and highlights the promising applications of nanomaterials in combating mango malformation. Hence, the present review aims to provide brief information on the disease and effective management strategies.
    Matched MeSH terms: Nanoparticles/chemistry
  2. Fulltext Neuroprotective properties of zinc oxide nanoparticles: therapeutic implications for Parkinson's disease
    Tang KS, See WZC, Naidu R
    Biosci Rep, 2024 Nov 27;44(11).
    PMID: 39501749 DOI: 10.1042/BSR20241102
    Parkinson's disease (PD) significantly affects millions of people worldwide due to the progressive degeneration of dopamine-producing neurons in the substantia nigra pars compacta. Despite extensive research efforts, effective treatments that can halt or reverse the progression of PD remain elusive. In recent years, nanotechnology has emerged as a promising new avenue for addressing this challenge, with zinc oxide nanoparticles (ZnO-NPs) standing out for their extensive therapeutic potential. ZnO-NPs have shown remarkable promise in neuroprotection through several key mechanisms. The multifaceted properties of ZnO-NPs suggest that they could play a crucial role in intervening across various fundamental mechanisms implicated in PD. By targeting these mechanisms, ZnO-NPs offer new insights and potential strategies for managing and treating PD. This review aims to provide a thorough examination of the molecular mechanisms through which ZnO-NPs exert their neuroprotective effects. It highlights their potential as innovative therapeutic agents for PD and outlines directions for future research to explore and harness their full capabilities.
    Matched MeSH terms: Nanoparticles/chemistry; Metal Nanoparticles/chemistry
  3. Eco-friendly zinc oxide nanoparticle biosynthesis powered by probiotic bacteria
    Al-Tameemi AI, Masarudin MJ, Rahim RA, Mizzi R, Timms VJ, Isa NM, et al.
    Appl Microbiol Biotechnol, 2025 Jan 29;109(1):32.
    PMID: 39878901 DOI: 10.1007/s00253-024-13355-4
    The rapid advancement of nanotechnology, particularly in the realm of pharmaceutical sciences, has significantly transformed the potential for treating life-threatening diseases. A pivotal aspect of this evolution is the emergence of "green nanotechnology," which emphasizes the environmentally sustainable synthesis of raw materials through biological processes. This review focuses on the biological synthesis and application of zinc oxide (ZnO) nanoparticles (NPs) from probiotic bacteria, particularly those sourced from wastewater. Microorganisms from wastewater tolerate harmful elements and enzymatically convert toxic heavy metals into eco-friendly materials. These probiotic bacteria are instrumental in the synthesis of ZnO NPs and exhibit remarkable antimicrobial properties with diverse industrial applications. As the challenge of drug-resistant pathogens escalates, innovative strategies for combating microbial infections are essential. This review explores the intersection of nanotechnology, microbiology, and antibacterial resistance, highlighting the importance of selecting suitable probiotic bacteria for synthesizing ZnO NPs with potent antibacterial activity. Additionally, the review addresses the biofunctionalization of NPs and their applications in environmental remediation and therapeutic innovations, including wound healing, antibacterial, and anticancer treatments. Eco-friendly NP synthesis relies on the identification of these suitable microbial "nano-factories." Targeting probiotic bacteria from wastewater can uncover new microbial NP synthesis capabilities, advancing environmentally friendly NP production methods. KEY POINTS: • Innovative strategies are needed to combat drug-resistant pathogens like MRSA. • Wastewater-derived probiotic bacteria are an eco-friendly method for ZnO synthesis. • ZnO NPs show significant antimicrobial activity against various pathogens.
    Matched MeSH terms: Nanoparticles/chemistry; Metal Nanoparticles/chemistry
  4. Fulltext Flow past a permeable stretching/shrinking sheet in a nanofluid using two-phase model
    Zaimi K, Ishak A, Pop I
    PLoS One, 2014;9(11):e111743.
    PMID: 25365118 DOI: 10.1371/journal.pone.0111743
    The steady two-dimensional flow and heat transfer over a stretching/shrinking sheet in a nanofluid is investigated using Buongiorno's nanofluid model. Different from the previously published papers, in the present study we consider the case when the nanofluid particle fraction on the boundary is passively rather than actively controlled, which make the model more physically realistic. The governing partial differential equations are transformed into nonlinear ordinary differential equations by a similarity transformation, before being solved numerically by a shooting method. The effects of some governing parameters on the fluid flow and heat transfer characteristics are graphically presented and discussed. Dual solutions are found to exist in a certain range of the suction and stretching/shrinking parameters. Results also indicate that both the skin friction coefficient and the local Nusselt number increase with increasing values of the suction parameter.
    Matched MeSH terms: Nanoparticles/chemistry*
  5. Sonochemical synthesis of gold nanoparticles by using high intensity focused ultrasound
    Yusof NS, Ashokkumar M
    Chemphyschem, 2015 Mar 16;16(4):775-81.
    PMID: 25598360 DOI: 10.1002/cphc.201402697
    The sonochemical synthesis of gold nanoparticles (GNPs) with different shapes and size distributions by using high-intensity focused ultrasound (HIFU) operating at 463 kHz is reported. GNP formation proceeds through the reduction of Au(3+) to Au(0) by radicals generated by acoustic cavitation. TEM images reveal that GNPs show irregular shapes at 30 W, are primarily icosahedral at 50 W and form a significant amount of nanorods at 70 W. The size of GNPs decreases with increasing acoustic power with a narrower size distribution. Sonochemiluminescence images help in the understanding of the effect of HIFU in controlling the size and shapes of GNPs. The number of radicals that form and the mechanical forces that are generated control the shape and size of the GNPs. UV/Vis spectra and TEM images are used to propose a possible mechanism for the observed effects. The results presented demonstrate, for the first time, that the HIFU system can be used to synthesise size- and shape-controlled metal nanoparticles.
    Matched MeSH terms: Metal Nanoparticles/chemistry*
  6. Recent Advances in Self-Assembled Nanoparticles for Drug Delivery
    Varma LT, Singh N, Gorain B, Choudhury H, Tambuwala MM, Kesharwani P, et al.
    Curr Drug Deliv, 2020;17(4):279-291.
    PMID: 32039683 DOI: 10.2174/1567201817666200210122340
    The collection of different bulk materials forms the nanoparticles, where the properties of the nanoparticle are solely different from the individual components before being ensembled. Selfassembled nanoparticles are basically a group of complex functional units that are formed by gathering the individual bulk components of the system. It includes micelles, polymeric nanoparticle, carbon nanotubes, liposomes and niosomes, etc. This self-assembly has progressively heightened interest to control the final complex structure of the nanoparticle and its associated properties. The main challenge of formulating self-assembled nanoparticle is to improve the delivery system, bioavailability, enhance circulation time, confer molecular targeting, controlled release, protection of the incorporated drug from external environment and also serve as nanocarriers for macromolecules. Ultimately, these self-assembled nanoparticles facilitate to overcome the physiological barriers in vivo. Self-assembly is an equilibrium process where both individual and assembled components are subsisting in equilibrium. It is a bottom up approach in which molecules are assembled spontaneously, non-covalently into a stable and welldefined structure. There are different approaches that have been adopted in fabrication of self-assembled nanoparticles by the researchers. The current review is enriched with strategies for nanoparticle selfassembly, associated properties, and its application in therapy.
    Matched MeSH terms: Nanoparticles/chemistry*
  7. Isolation and characterization of nanocrystalline cellulose from roselle-derived microcrystalline cellulose
    Kian LK, Jawaid M, Ariffin H, Karim Z
    Int J Biol Macromol, 2018 Jul 15;114:54-63.
    PMID: 29551511 DOI: 10.1016/j.ijbiomac.2018.03.065
    Roselle fiber is a renewable and sustainable agricultural waste enriched with cellulose polysaccharides. The isolation of Nanocrystalline cellulose (NCC) from roselle-derived microcrystalline cellulose (MCC) is an alternative approach to recover the agricultural roselle plant residue. In the present study, acid hydrolysis with different reaction time was carried out to degrade the roselle-derived MCC to form NCC. The characterizations of isolated NCC were conducted through Fourier Transform Infrared Ray (FTIR), Transmission Electron Microscopy (TEM), Field Emission Scanning Electron Microscopy (FESEM), Atomic Force Microscopy (AFM), Dynamic Light Scattering (DLS), Energy Dispersive Spectroscopy (EDS), X-ray Diffraction (XRD), Thermogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC). As evaluated from the performed morphological investigations, the needle-like shape NCC nanostructures were observed under TEM and AFM microscopy studies, while irregular rod-like shape of NCC was observed under FESEM analysis. With 60min hydrolysis time, XRD analysis demonstrated the highest NCC crystallinity degree with 79.5%. In thermal analysis by TGA and DSC, the shorter hydrolysis time tended to produce NCC with higher thermal stability. Thus, the isolated NCC from roselle-derived MCC has high potential to be used in application of pharmaceutical and biomedical fields for nanocomposite fabrication.
    Matched MeSH terms: Nanoparticles/chemistry*
  8. Fulltext Controlled assembly of superparamagnetic iron oxide nanoparticle into nanoliposome for Pickering emulsion preparation
    Sia CS, Tey BT, Goh BH, Low LE
    Colloids Surf B Biointerfaces, 2024 Sep;241:114051.
    PMID: 38954935 DOI: 10.1016/j.colsurfb.2024.114051
    There has been a surge in effort in the development of various solid nanoparticles as Pickering emulsion stabilizers in the past decades. Regardless, the exploration of stabilizers that simultaneously stabilize and deliver bioactive has been limited. For this, liposomes with amphiphilic nature have been introduced as Pickering emulsion stabilizers but these nano-sized vesicles lack targeting specificity. Therefore in this study, superparamagnetic iron oxide nanoparticles (SPION) encapsulated within liposomes (MLP) were used as Pickering emulsion stabilizers to prepare pH and magnetic-responsive Pickering emulsions. A stable MLP-stabilized Pickering emulsion formulation was established by varying the MLP pH, concentration, and oil loading during the emulsification process. The primary stabilization mechanism of the emulsion under pH variation was identified to be largely associated with the MLP phosphate group deprotonation. When subjected to sequential pH adjustment to imitate the gastrointestinal digestion pH environment, a recovery in Pickering emulsion integrity was observed as the pH changes from acidic to alkaline. By incorporating SPION, the Pickering emulsion can be guided to the targeted site under the influence of a magnetic field without compromising emulsion stability. Overall, the results demonstrated the potential of MLP-stabilized Pickering emulsion as a dual pH- and magnetic-responsive drug delivery carrier with the ability to co-encapsulate hydrophobic and hydrophilic bioactive.
    Matched MeSH terms: Magnetite Nanoparticles/chemistry
  9. Synergistic Antibacterial Effect of ZnO Nanoparticles and Antibiotics against Multidrug-resistant Biofilm Bacteria
    Masadeh MM, Bany-Ali NM, Khanfar MS, Alzoubi KH, Masadeh MM, Al Momany EM
    Curr Drug Deliv, 2025;22(1):92-106.
    PMID: 38231065 DOI: 10.2174/0115672018279213240110045557
    BACKGROUND: The misuse of antibiotics leads to a global increase in antibiotic resistance. Therefore, it is imperative to search for alternative compounds to conventional antibiotics. ZnO nanoparticles (Zn NP) are one of these alternatives because they are an effective option to overcome biofilm bacterial cells and a novel way to overcome multidrug resistance in bacteria. The current research study aims to characterize the efficacy of ZnO nanoparticles alone and in combination with other antibacterial drugs against bacterial biofilms.

    METHODS: ZnO NPs were prepared by co-precipitation method, and their anti-biofilm and antibacterial activities alone or combined with four types of broad-spectrum antibacterial (Norfloxacin, Colistin, Doxycycline, and Ampicillin) were evaluated against E. coli and S. aureus bacterial strains. Finally, the cytotoxicity and the hemolytic activity were evaluated.

    RESULTS: ZnO NPs were prepared, and results showed that their size was around 10 nm with a spherical shape and a zeta potential of -21.9. In addition, ZnO NPs were found to have a strong antibacterial effect against Gram-positive and Gram-negative microorganisms, with a minimum inhibitory concentration (MIC) of 62.5 and 125 μg/mL, respectively. Additionally, they could eradicate biofilmforming microorganisms at a concentration of 125 μg/m. ZnO NPs were found to be non-toxic to erythrocyte cells. Still, some toxicity was observed for Vero cells at effective concentration ranges needed to inhibit bacterial growth and eradicate biofilm-forming organisms. When combined with different antibacterial, ZnO NP demonstrated synergistic and additive effects with colistin, and the MIC and MBEC of the combination decreased significantly to 0.976 μg/mL against planktonic and biofilm strains of MDR Gram-positive bacteria, resulting in significantly reduced toxicity.

    CONCLUSION: The findings of this study encourage the development of alternative therapies with high efficacy and low toxicity. ZnO nanoparticles have demonstrated promising results in overcoming multi-drug resistant bacteria and biofilms, and their combination with colistin has shown a significant reduction in toxicity. Further studies are needed to investigate the potential of ZnO nanoparticles as a viable alternative to conventional antibiotics.

    Matched MeSH terms: Nanoparticles/chemistry; Metal Nanoparticles/chemistry
  10. Chemical free, bio-Intercalation of selenium nanoparticles for highly accelerated photo-responsive of organic contaminants debasement and their in-vitro anti-bacterial agents, anti-oxidants effect, cyto-toxic analysis
    Rajendran J, Jeyaraman P, Sakthivel E, Almansour AI, Arumugam N, Raja PB
    Environ Res, 2024 Oct 15;259:119479.
    PMID: 38964575 DOI: 10.1016/j.envres.2024.119479
    This study investigates the use of Excoecaria agallocha leaves as a bio-template for the intercalation of Selenium nanoparticles (SeNPs). The synthesized SeNPs were characterized using techniques like SEM-EDX, TEM/HR-TEM, and XRD spectroscopic studies. The study found that SeNPs showed maximum cleaning ability at a dosage of 50 μl/mL, with 95% inhibition of DPPH radicals. However, cellular absorption was limited to 55% at concentrations of 300 μg/L over a 72-h period. The synthesized SeNPs also demonstrated a strong cytotoxic effect on MCF-7 breast cancer cell lines, indicating their potential as anti-cancer agents. Further research is needed to fully explore the potential of these novel nanocomposites.
    Matched MeSH terms: Nanoparticles/chemistry; Metal Nanoparticles/chemistry
  11. Numerical study of the enhancement of heat transfer for hybrid CuO-Cu Nanofluids flowing in a circular pipe
    Balla HH, Abdullah S, Mohdfaizal W, Zulkifli R, Sopian K
    J Oleo Sci, 2013;62(7):533-9.
    PMID: 23823920
    A numerical simulation model for laminar flow of nanofluids in a pipe with constant heat flux on the wall was built to study the effect of the Reynolds number on convective heat transfer and pressure loss. The investigation was performed for hybrid nanofluids consisting of CuO-Cu nanoparticles and compared with CuO and Cu in which the nanoparticles have a spherical shape with size 50, 50, 50nm respectively. The nanofluids were prepared, following which the thermal conductivity and dynamic viscosity were measured for a range of temperatures (10 -60°C). The numerical results obtained were compared with the existing well-established correlation. The prediction of the Nusselt number for nanofluids agrees well with the Shah correlation. The comparison of heat transfer coefficients for CuO, Cu and CuO-Cu presented an increase in thermal conductivity of the nanofluid as the convective heat transfer coefficient increased. It was found that the pressure loss increases with an increase in the Reynolds number, nanoparticle density and particle volume fraction. However, the flow demonstrates enhancement in heat transfer which becomes greater with an increase in the Reynolds number for the nanofluid flow.
    Matched MeSH terms: Nanoparticles/chemistry*
  12. Fulltext Fabrication of silver nanoparticles dispersed in palm oil using laser ablation
    Zamiri R, Zakaria A, Ahangar HA, Sadrolhosseini AR, Mahdi MA
    Int J Mol Sci, 2010;11(11):4764-70.
    PMID: 21151470 DOI: 10.3390/ijms11114764
    In this study we used a laser ablation technique for preparation of silver nanoparticles. The fabrication process was carried out by ablation of a silver plate immersed in palm oil. A pulsed Nd:YAG laser at a wavelength of 1064 nm was used for ablation of the plate at different times. The palm coconut oil allowed formation of nanoparticles with very small and uniform particle size, which are dispersed very homogeneously within the solution. The obtained particle sizes for 15 and 30 minute ablation times were 2.5 and 2 nm, respectively. Stability study shows that all of the samples remained stable for a reasonable period of time.
    Matched MeSH terms: Metal Nanoparticles/chemistry*
  13. Fulltext Advanced in developmental organic and inorganic nanomaterial: a review
    Khalid K, Tan X, Mohd Zaid HF, Tao Y, Lye Chew C, Chu DT, et al.
    Bioengineered, 2020 12;11(1):328-355.
    PMID: 32138595 DOI: 10.1080/21655979.2020.1736240
    With the unique properties such as high surface area to volume ratio, stability, inertness, ease of functionalization, as well as novel optical, electrical, and magnetic behaviors, nanomaterials have a wide range of applications in various fields with the common types including nanotubes, dendrimers, quantum dots, and fullerenes. With the aim of providing useful insights to help future development of efficient and commercially viable technology for large-scale production, this review focused on the science and applications of inorganic and organic nanomaterials, emphasizing on their synthesis, processing, characterization, and applications on different fields. The applications of nanomaterials on imaging, cell and gene delivery, biosensor, cancer treatment, therapy, and others were discussed in depth. Last but not least, the future prospects and challenges in nanoscience and nanotechnology were also explored.
    Matched MeSH terms: Nanoparticles/chemistry
  14. Properties and characteristics of nanocrystalline cellulose isolated from olive fiber
    Kian LK, Saba N, Jawaid M, Alothman OY, Fouad H
    Carbohydr Polym, 2020 Aug 01;241:116423.
    PMID: 32507177 DOI: 10.1016/j.carbpol.2020.116423
    Olive fiber is a sustainable material as well as alternative biomass for extraction of nanocrystalline cellulose (NCC), which has been widely applied in various industries. In the present study, ONC-I, ONC-II, and ONC-III were extracted from olive stem fiber at different hydrolysis reaction times of 30 min, 45 min, and 60 min, respectively. The nanoparticle size was found gradually reducing from ONC-I (11.35 nm width, 168.28 nm length) to ONC-III (6.92 nm width, 124.16 nm length) due to the disintegration of cellulose fibrils. ONC-II and ONC-III possessed highly pure cellulose compartments and enhanced crystals structure. This study also showed that rigidity increased from ONC-I to ONC-II. ONC-III showed the highest crystallinity of 83.1 %, endowing it as a potentially reliable load-bearing agent. Moreover, ONC-III exhibited highest stable heat resistance among the chemically-isolated nanocellulose. We concluded that olive NCC could be promising materials for a variety of industrial applications in various fields.
    Matched MeSH terms: Nanoparticles/chemistry*
  15. Carbon dioxide conversion over carbon-based nanocatalysts
    Khavarian M, Chai SP, Mohamed AR
    J Nanosci Nanotechnol, 2013 Jul;13(7):4825-37.
    PMID: 23901504
    The utilization of carbon dioxide for the production of valuable chemicals via catalysts is one of the efficient ways to mitigate the greenhouse gases in the atmosphere. It is known that the carbon dioxide conversion and product yields are still low even if the reaction is operated at high pressure and temperature. The carbon dioxide utilization and conversion provides many challenges in exploring new concepts and opportunities for development of unique catalysts for the purpose of activating the carbon dioxide molecules. In this paper, the role of carbon-based nanocatalysts in the hydrogenation of carbon dioxide and direct synthesis of dimethyl carbonate from carbon dioxide and methanol are reviewed. The current catalytic results obtained with different carbon-based nanocatalysts systems are presented and how these materials contribute to the carbon dioxide conversion is explained. In addition, different strategies and preparation methods of nanometallic catalysts on various carbon supports are described to optimize the dispersion of metal nanoparticles and catalytic activity.
    Matched MeSH terms: Metal Nanoparticles/chemistry*
  16. Characterization of natural gums via elemental and chemometric analyses, synthesis of silver nanoparticles, and biological and catalytic applications
    Jamila N, Khan N, Hwang IM, Saba M, Khan F, Amin F, et al.
    Int J Biol Macromol, 2020 Mar 15;147:853-866.
    PMID: 31739066 DOI: 10.1016/j.ijbiomac.2019.09.245
    Gums; composed of polysaccharides, carbohydrates, proteins, and minerals, are high molecular weight hydrophilic compounds with several biological applications. This study describes the nutritional and toxic elements content, chemical composition, synthesis of silver nanoparticles (G-AgNPs), and pharmacological and catalytic properties of Prunus armeniaca (apricot), Prunus domestica (plums), Prunus persica (peaches), Acacia modesta (phulai), Acacia arabica (kikar), and Salmalia malabarica (silk cotton tree) gums. The elemental contents were analyzed by inductively coupled plasma-optical emission spectroscopy (ICP-OES) and ICP-mass spectrometry (ICP-MS). NMR spectroscopy was used for the identification of class of compounds in the mixture, their functional groups were determined through FTIR techniques, and plasmon resonance and size of G-AgNPs through UV-Vis spectroscopic technique and transmission electron microscopy (TEM). From the results, nutritional elements were present at appreciable concentrations, whereas toxic elements showed content below the maximum permissible ranges. Using the elemental data, linear discriminant and principal component analyses classified the gums to 99.9% variability index. Furthermore, G-AgNPs exhibited significant antioxidant, antibacterial, and redox catalytic potential. Hence, the subject G-AgNPs could have promising nutritional, therapeutic and environmental remediation applications.
    Matched MeSH terms: Metal Nanoparticles/chemistry*
  17. Investigation of optimal conditions for production of highly crystalline nanocellulose with increased yield via novel Cr(III)-catalyzed hydrolysis: Response surface methodology
    Chen YW, Lee HV, Abd Hamid SB
    Carbohydr Polym, 2017 Dec 15;178:57-68.
    PMID: 29050615 DOI: 10.1016/j.carbpol.2017.09.029
    For the first time, a highly efficient Cr(NO3)3 catalysis system was proposed for optimization the yield and crystallinity of nanocellulose end product. A five-level three-factor central composite design coupled with response surface methodology was employed to elucidate parameters interactions between three design factors, namely reaction temperature (x1), reaction time (x2) and concentration of Cr(NO3)3 (x3) over a broad range of process conditions and determine the effect on crystallinity index and product yield. The developed models predicted the maximum nanocellulose yield of 87% at optimum process conditions of 70.6°C, 1.48h, and 0.48M Cr(NO3)3. At these conditions, the obtained nanocellulose presented high crystallinity index (75.3%), spider-web-like interconnected network morphology with the average width of 31.2±14.3nm. In addition, the yielded nanocellulose rendered a higher thermal stability than that of original cellulosic source and expected to be widely used as reinforcement agent in bio-nanocomposites materials.
    Matched MeSH terms: Nanoparticles/chemistry*
  18. Fulltext Investigation of micro- and nanosized particle erosion in a 90° pipe bend using a two-phase discrete phase model
    Safaei MR, Mahian O, Garoosi F, Hooman K, Karimipour A, Kazi SN, et al.
    ScientificWorldJournal, 2014;2014:740578.
    PMID: 25379542 DOI: 10.1155/2014/740578
    This paper addresses erosion prediction in 3-D, 90° elbow for two-phase (solid and liquid) turbulent flow with low volume fraction of copper. For a range of particle sizes from 10 nm to 100 microns and particle volume fractions from 0.00 to 0.04, the simulations were performed for the velocity range of 5-20 m/s. The 3-D governing differential equations were discretized using finite volume method. The influences of size and concentration of micro- and nanoparticles, shear forces, and turbulence on erosion behavior of fluid flow were studied. The model predictions are compared with the earlier studies and a good agreement is found. The results indicate that the erosion rate is directly dependent on particles' size and volume fraction as well as flow velocity. It has been observed that the maximum pressure has direct relationship with the particle volume fraction and velocity but has a reverse relationship with the particle diameter. It also has been noted that there is a threshold velocity as well as a threshold particle size, beyond which significant erosion effects kick in. The average friction factor is independent of the particle size and volume fraction at a given fluid velocity but increases with the increase of inlet velocities.
    Matched MeSH terms: Nanoparticles/chemistry*
  19. The reuse of wastepaper for the extraction of cellulose nanocrystals
    Danial WH, Abdul Majid Z, Mohd Muhid MN, Triwahyono S, Bakar MB, Ramli Z
    Carbohydr Polym, 2015 Mar 15;118:165-9.
    PMID: 25542122 DOI: 10.1016/j.carbpol.2014.10.072
    The study reports on the preparation of cellulose nanocrystals (CNCs) from wastepaper, as an environmental friendly approach of source material, which can be a high availability and low-cost precursor for cellulose nanomaterial processing. Alkali and bleaching treatments were employed for the extraction of cellulose particles followed by controlled-conditions of acid hydrolysis for the isolation of CNCs. Attenuated total reflectance Fourier Transform Infrared (ATR FTIR) spectroscopy was used to analyze the cellulose particles extracted while Transmission electron microscopy images confirmed the presence of CNCs. The diameters of CNCs are in the range of 3-10nm with a length of 100-300nm while a crystallinity index of 75.9% was determined from X-ray diffraction analysis. The synthesis of this high aspect ratio of CNCs paves the way toward alternative reuse of wastepaper in the production of CNCs.
    Matched MeSH terms: Nanoparticles/chemistry*
  20. Fulltext Titanium dioxide as a catalyst support in heterogeneous catalysis
    Bagheri S, Muhd Julkapli N, Bee Abd Hamid S
    ScientificWorldJournal, 2014;2014:727496.
    PMID: 25383380 DOI: 10.1155/2014/727496
    The lack of stability is a challenge for most heterogeneous catalysts. During operations, the agglomeration of particles may block the active sites of the catalyst, which is believed to contribute to its instability. Recently, titanium oxide (TiO2) was introduced as an alternative support material for heterogeneous catalyst due to the effect of its high surface area stabilizing the catalysts in its mesoporous structure. TiO2 supported metal catalysts have attracted interest due to TiO2 nanoparticles high activity for various reduction and oxidation reactions at low pressures and temperatures. Furthermore, TiO2 was found to be a good metal oxide catalyst support due to the strong metal support interaction, chemical stability, and acid-base property. The aforementioned properties make heterogeneous TiO2 supported catalysts show a high potential in photocatalyst-related applications, electrodes for wet solar cells, synthesis of fine chemicals, and others. This review focuses on TiO2 as a support material for heterogeneous catalysts and its potential applications.
    Matched MeSH terms: Nanoparticles/chemistry*
Related Terms
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links