Displaying publications 41 - 60 of 625 in total

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  1. Fulltext Systematic review of toxicity profiles on Nano-TiO2 for cancer therapy
    Nur Hazirah Mohd Azlan, Rabiatul Basria S.M.N. Mydin, Manganting, Ernest
    Malaysian Journal of Medicine and Health Sciences, 2018;14(102):1-7.
    MyJurnal
    With the increasing clinical use of titanium dioxide nanoparticles (nano-TiO2), a better understanding of their safety in the human use is critical. The present study aims to review the potential application of nano-TiO2 as targeted cancer therapy based on their toxicity risk which highly dependent on their physio-chemical properties. Methods: This review was performed based on PRISMA-P protocol that begin with literature searching on the selected databases; PubMed, Springer Link, Science Direct and general search engine; Google Scholar from 2013 to 2018. Studies retrieved by the pre-determined keywords (titanium dioxide nanoparticles, toxicity, genotoxicity, cytotoxicity, targeted cancer therapy) that assessed toxicity risk of nano-TiO2 in cancer therapeutics were included. Results: The search retrieved 252 articles. Assessment of eligibility by application of inclusion criteria yielded 14 articles. Nano-TiO2 induced cytotoxicity and genotoxicity in dose and time-dependent manner killing the cancerous cells. All studies used primary particles size < 100 nm with mean of 39.38 and standard deviation of 30.47 which is lower than the mean denoting diameter distribution from selected studies are concentrated from the mean. Conclusion: This review suggest that TiO2 nanoparticles can be considered as an ideal candidate for drug-delivery vehicle for targeted cancer therapy by specifically tailored their physio-chemical properties of this nanoparticles according to desired target site and functions to ensure its optimal efficacy.
    Matched MeSH terms: Particle Size
  2. Combustion characteristics of refuse derived fuel (RDF) in a fluidized bed combustor
    Johari A, Mat R, Alias H, Hashim H, Hassim M, Zakaria Z, et al.
    Sains Malaysiana, 2014;43:103-109.
    The combustion characteristics of refuse derived fuel (RDF) in a fluidized bed have been studied. The gross heating value (GHv) of the RDF was 14.43 MJIkg with moisture content of 25% by weight. Parameters of interest for sustainable bed combustion were the fluidization number and primary air factor. The study was performed in a rectangular fluidized bed combustor with dimensions of 0.3 m in width, 0.7 m in length and 2 m in height. Sand with mean particle size of 0.34 mm was used as a fluidization medium. The sand bed height was at 0.3 m above the standpipes air distributor. The range of fluidization number under investigation was 5-7 II fin which 5 II newas found to be the optimum. The study was continued for the determination of the optimum primary air factor with the selected range of primary air factors being 0.6, 0.8, 1.0 and 12 in experiments conducted at 5 Unit The final results showed that the optimum primary air factor was at 0.8. An energy balance was also performed to determine the thermal efficiency of the combustion. It was concluded that the thermal efficiency depended on the bed temperature and the primary air factor being used.
    Matched MeSH terms: Particle Size
  3. Fulltext The role of silica-containing agro-industrial waste as reinforcement on physicochemical and thermal properties of polymer composites
    Rizal S, Fizree HM, Hossain MS, Ikramullah, Gopakumar DA, Wan Ni EC, et al.
    Heliyon, 2020 Mar;6(3):e03550.
    PMID: 32190763 DOI: 10.1016/j.heliyon.2020.e03550
    This study was conducted to determine the influence of the oil palm boiler ash (OPBA) reinforcement on the microstructural, physical, mechanical and thermal properties of epoxy polymer composites. The chemical composition analysis of OPBA revealed that it contains about 55 wt.% of SiO2 along with other metallic oxides and elements. The surface morphology of OPBA showed angular and irregular shapes with porous structures. The influence of OPBA as a reinforcement in epoxy composite was studied with varying filler loadings (10-50 wt.%) and different particle sizes (50-150 μm). The result showed that the incorporation of OPBA in composites has improved the physical, mechanical and thermal properties of the epoxy matrix. The highest physical and mechanical properties of fabricated composites were attained with 30 wt.% loading and size of 50 μm. Also, thermal stability and the percentage of char residue of the composite increased with increasing filler loading. Furthermore, the contact angle of OPBA reinforced epoxy composites increased with the increase of filler loading. The lowest value of the contact angle was obtained at 30 wt.% of filler loading with the OPBA particle size of 50 μm. The finding of this study reveals that the OPBA has the potential to be used as reinforcement or filler as well as an alternative of silica-based inorganic fillers used in the enhancement of mechanical, physical and thermal properties of the epoxy polymer composite.
    Matched MeSH terms: Particle Size
  4. Novel Nanostructured Lipid Carriers Co-Loaded with Mesalamine and Curcumin: Formulation, Optimization and In Vitro Evaluation
    Awasthi A, Kumar B, Gulati M, Vishwas S, Corrie L, Kaur J, et al.
    Pharm Res, 2022 Nov;39(11):2817-2829.
    PMID: 36195824 DOI: 10.1007/s11095-022-03401-z
    PURPOSE: The aim of current study is to formulate, optimize and characterize the developed formulation of Mesalamine-Curcumin Nanostructured Lipid Carriers (Mes-Cur NLCs).

    METHODS: It was formulated using high pressure homogenization followed by probe sonication and formulation variables were optimized using Central Composite Design. The particle size (PS), zeta potential (ZP), entrapment efficiency (EE), drug release, cytotoxicity on NIH 3T3 fibroblasts cells and HaCaT keratinocytes cells and efficacy on RAW264.7 cells for optimized formulation was determined.

    RESULTS: The PS, ZP and EE were found to be 85.26 nm, -23.7 ± 7.45 mV, 99.2 ± 2.62 % (Mes) and 84 ± 1.51 % (Cur), respectively. The good correlation between predicted and obtained value indicated suitability and reproducibility of experimental design. NLCs showed spherical shape as confirmed by TEM. In vitro drug release profile of prepared formulation showed that Mes exhibited 100 % release at 48 h, whereas Cur exhibited 82.23 ± 2.97% release at 120 h. Both the drugs exhibited sustained release upon incorporation into the NLCs. The absence of any significant cell death during MTT assay performed on NIH 3T3 fibroblasts cells and HaCaT keratinocytes cells indicated that NLCs' were safe for use. Furthermore, significant reduction in nitric oxide level during anti-inflammatory evaluation of formulation on RAW264.7 cells showed excellent potential for the formulation to treat inflammation. The formulation was found stable as no significant difference between the PS, ZP and EE of the fresh and aged NLCs was observed.

    CONCLUSION: The outcomes of study deciphered successful formulation of Mes-Cur NLCs.

    Matched MeSH terms: Particle Size
  5. Topologically directed confocal Raman imaging (TD-CRI): Advanced Raman imaging towards compositional and micromeritic profiling of a commercial tablet components
    Muthudoss P, Kumar S, Ann EYC, Young KJ, Chi RLR, Allada R, et al.
    J Pharm Biomed Anal, 2022 Feb 20;210:114581.
    PMID: 35026592 DOI: 10.1016/j.jpba.2022.114581
    Particle size distribution (PSD), spatial location and particle cluster size of ingredients, polymorphism, compositional distribution of a pharmaceutical product are few of the most important attributes in establishing the drug release-controlling microstructural and solid state properties that would be used to (re)design or reproduce similar products. There are numerous solid-state techniques available for PSD analysis. Laser diffraction (LD) is mostly used to study PSD of raw materials. However, a constraint of LD is the interference between the active pharmaceutical ingredients (API) and excipients, where it is very challenging to measure API size in a tablet. X-ray powder diffraction (XRPD) is widely employed in establishing the polymorphism of API and excipients. This research examined a commercial osmotic tablet in terms of extracting solid state properties of API and functional excipient by Raman Imaging. Establishing repeatability, reproducibility, and sample representativeness when the samples are non-uniform and inhomogeneous necessitates multiple measurements. In such scenarios, when employing imaging-based techniques, it can be time-consuming and tedious. Advanced statistical methodologies are used to overcome these disadvantages and expedite the characterization process. Overall, this study demonstrates that Raman imaging can be employed as a non-invasive and effective offline method for assessing the solid-state characteristics of API and functional excipients in complex dosage forms like osmotic tablets.
    Matched MeSH terms: Particle Size
  6. Fulltext Ultrasound-assisted encapsulation of Pandan (Pandanus amaryllifolius) extract
    Omer N, Choo YM, Ahmad N, Mohd Yusof NS
    Ultrason Sonochem, 2021 Nov;79:105793.
    PMID: 34673338 DOI: 10.1016/j.ultsonch.2021.105793
    Pandan (Pandanus amaryllifolius) is commonly used as a food ingredient in Southeast Asia due to its delicious flavor, appetizing aroma and bright green colour. Pandan plant is uniquely found only in certain parts of the world. Despite its increasing popularity worldwide, its export market is limited by practical issues. One of the main problems for exporting Pandan to global market is its stability during transport. Due to the volatility of its active constituent, the functional properties of Pandan are lost during storage and shipment. In this study, we explored the ability of ultrasound processing technology to encapsulate the aromatic Pandan extract using lysozyme or chitosan as a shell material. 20 kHz ultrasonicator was used to encapsulate the pandan extract at 150 W of applied power. Two parameters, the ultrasonic probe tip and the core-to-shell ratio were varied to control the properties of the encapsulates. The diameters of the probe tip used were 0.3 and 1.0 cm. The core-to-shell volume ratios used were 1:160 and 1:40. The size distribution and the stability of the synthesized microspheres were characterized to understand and explore the possible parameters variation impact. Both size and size distribution of the microspheres were found to be influenced by the parameters varied to certain extent. The results showed that the mean size of the microspheres was generally smallest when using 1 cm probe tip with lower core-to-shell volume ratio but largest when using the 3 mm tip with higher core-to-shell volume ratio. This indicates that the sonication parameters could be fine-tuned to achieve the encapsulation of Pandan extract for storage and export. The pandan-encapsulated microspheres were also found to be stable during storage at least for one month.
    Matched MeSH terms: Particle Size
  7. Physicochemical stability, antioxidant activity, and antimicrobial activity of quercetin-loaded zein nanoparticles coated with dextrin-modified anionic polysaccharides
    Zhang Z, Hu Y, Ji H, Lin Q, Li X, Sang S, et al.
    Food Chem, 2023 Jul 30;415:135736.
    PMID: 36863232 DOI: 10.1016/j.foodchem.2023.135736
    Core-shell biopolymer nanoparticles are assembled from a hydrophobic protein (zein) core and a hydrophilic polysaccharide (carboxymethyl dextrin) shell. The nanoparticles were shown to have good stability and the ability to protect quercetin from chemical degradation under long-term storage, pasteurization, and UV irradiation. Spectroscopy analysis shows that electrostatic, hydrogen bonding, and hydrophobic interactions are the main driving forces for the formation of composite nanoparticles. Quercetin coated with nanoparticles significantly enhanced its antioxidant and antibacterial activities and showed good stability and slow release in vitro during simulated gastrointestinal digestion. Furthermore, the encapsulation efficiency of carboxymethyl dextrin-coated zein nanoparticles (81.2%) for quercetin was significantly improved compared with that of zein nanoparticles alone (58.4%). These results indicate that carboxymethyl dextrin-coated zein nanoparticles can significantly improve the bioavailability of hydrophobic nutrient molecules such as quercetin and provide a valuable reference for their application in the field of biological delivery of energy drinks and food.
    Matched MeSH terms: Particle Size
  8. High-capacity glycol chitosan-based nanoemulsion for efficient delivery of disulfiram
    Abd Kadir E, Uchegbu IF, Schätzlein AG
    Int J Pharm, 2023 Jun 10;640:123036.
    PMID: 37169106 DOI: 10.1016/j.ijpharm.2023.123036
    Disulfiram (DS) is an anti-alcoholism drug capable of acting against important and hard-to-treat cancers. The drug's relative instability and variable absorption/distribution have led to its variable pharmacokinetics and suboptimal exposure. Hence, it was hypothesised that a nano-enabled form of DS might be able to overcome such limitations. Encapsulation of the labile DS was achieved with quaternary ammonium palmitoyl glycol chitosan (GCPQ) to form a high-capacity, soybean oil-based DS-GCPQ nanoemulsion. DS-GCPQ showed capability of oil-loading up to 50% v/v for a stable entrapment of high drug content. With increasing oil content (10 to 50% v/v), the mean particle size and polydispersity index were also increased (166 to 351 nm and 0.14 to 0.22, respectively) for a given amount of GCPQ. Formulations showed a highly positive particle surface charge (50.9 ± 1.3 mV), contributing to the colloidal stability of the individual particles. DS-GCPQ showed marked cytotoxicity against pancreatic cancer cell lines with enhanced activity in the presence of copper. An intravenous pharmacokinetic study of DS-GCPQ in vivo showed improved plasma drug stability with a DS half-life of 17 min. Prolonged survival was seen in tumour-bearing animals treated with DS-GCPQ supplemented with copper. In conclusion, DS-GCPQ nanoemulsion has the potential to be developed further for cancer therapeutic purposes.
    Matched MeSH terms: Particle Size
  9. Synthesis and characterization of sago starch nanocrystal laurate as a food grade particle emulsifier
    Ahmad A, Fazial FF, Khalil HPSA, Fazry S, Lazim A
    Int J Biol Macromol, 2023 Jul 01;242(Pt 2):124816.
    PMID: 37182623 DOI: 10.1016/j.ijbiomac.2023.124816
    Starch nanocrystals (SNCs) are tiny particles that possess unique qualities due to their small size, such as increased crystallinity, thin sheet structure, low permeability, and strong resistance to digestion. Although sago starch nanocrystals (SNCs) are naturally hydrophilic, their properties can be modified through chemical modifications to make them more versatile for various applications. In this study, the esterification process was used to modify SNCs using lauroyl chloride (LC) to enhance their surface properties. Three different ratios of LC to SNC were tested to determine the impact on the modified SNC (mSNC). The chemical changes in the mSNC were analyzed using FTIR and 1H NMR spectroscopy. ##The results showed that as the amount of LC increased, the degree of substitution (DS) also increased, which reduced the crystallinity of the mSNC and its thermal stability. However, the esterification process also improved the hydrophobicity of the SNC, making it more amphiphilic. The emulsification capabilities of the mSNC were investigated using a Pickering emulsion, and the results showed that the emulsion made from mSNC-1.0 had better stability than the one made from pristine SNC. This study highlights the potential of SNC as a particle emulsifier and demonstrates how esterification can improve its emulsification capabilities.
    Matched MeSH terms: Particle Size
  10. Tunability of Pickering particle features of whey protein isolate via remodeling partial unfolding during ultrasonication-assisted complexation with chitosan/chitooligosaccharide
    Yu H, Zheng Y, Zhou C, Liu L, Wang L, Cao J, et al.
    Carbohydr Polym, 2024 Feb 01;325:121583.
    PMID: 38008470 DOI: 10.1016/j.carbpol.2023.121583
    The potential of ultrasonication-driven molecular self-assembly of whey protein isolate (WPI) with chitosan (CS)/chitooligosaccharide (COS) to stabilize Pickering emulsions was examined, based on CS/COS ligands-induced partial unfolding in remodeling the Pickering particles features. Multi-spectral analysis suggested obvious changes in conformational structures of WPI due to interaction with CS/COS, with significantly higher unfolding degrees of WPI induced by COS. Non-covalent interactions were identified as the major forces for WPI-CS/COS conjugates. Ultrasonication enhanced electrostatic interaction between CS's -NH3 groups and WPI's -COO- groups which improved emulsification activity and storability of WPI-COS stabilized Pickering emulsion. This was attributed to increased surface hydrophobicity and decreased particle size compared to WPI-CS associated with differential unfolding degrees induced by different saccharide ligands. CLSM and SEM consistently observed smaller emulsion droplets in WPI-COS complexes than WPI-CS/COS particles tightly adsorbed at the oil-water interface. The electrostatic self-assembly of WPI with CS/COS greatly enhanced the encapsulation efficiency of quercetin than those stabilized by WPI alone and ultrasound further improved encapsulation efficiency. This corresponded well with the quantitative affinity parameters between quercetin and WPI-CS/COS complexes. This investigation revealed the great potential of glycan ligands-induced conformational transitions of extrinsic physical disruption in tuning Pickering particle features.
    Matched MeSH terms: Particle Size
  11. Pickering emulsions stabilized by chitosan-flaxseed gum-hyaluronic acid nanoparticles for controlled topical release of ferulic acid
    Li G, Li J, Lee YY, Qiu C, Zeng X, Wang Y
    Int J Biol Macromol, 2024 Jan;255:128086.
    PMID: 37981278 DOI: 10.1016/j.ijbiomac.2023.128086
    Chitosan (CS) based nanoparticles (NPs) were fabricated via an ionic gelation reaction modified by flaxseed gum (FG) or sodium tripolyphosphate (STPP). The average particle size, morphology, interfacial tension, and wettability of NPs were characterized. The particle size of CS-STPP-HA (hyaluronic acid)-FA (ferulic acid) NPs and CS-FG-HA-FA NPs was 400.8 nm and 262.4 nm, respectively under the optimized conditions of CS/STPP = 5:1 (w/w) or CS/FG = 1:1 (v/v) with HA concentration of 0.25 mg/mL and FA dosage of 25 μM. FG acted as a good alternative for STPP to form particles with CS in stabilizing Pickering emulsion with an internal diacylglycerol (DAG) phase of 50-80 % (v/v). The complex nanoparticles had high surface activity and contact angle close to 90 °C, being able to tightly packed at the droplet surface. The emulsions had high thermal, ionic and oxidative stability. With the aid of moisturizing polysaccharides and DAG oil, the emulsions had a good sustained-release ability for FA with deeper penetration and retention into the dermis of the skin. Thus, FG and HA-based NPs serve as green vehicles for the fabrication of novel Pickering emulsions and possess great potential to be applied as a delivery system for lipophilic active agents in functional food and cosmetic products.
    Matched MeSH terms: Particle Size
  12. 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: Particle Size
  13. Fulltext Preparation of astaxanthin nanodispersions using gelatin-based stabilizer systems
    Anarjan N, Nehdi IA, Sbihi HM, Al-Resayes SI, Malmiri HJ, Tan CP
    Molecules, 2014 Sep 10;19(9):14257-65.
    PMID: 25211006 DOI: 10.3390/molecules190914257
    The incorporation of lipophilic nutrients, such as astaxanthin (a fat soluble carotenoid) in nanodispersion systems can either increase the water solubility, stability and bioavailability or widen their applications in aqueous food and pharmaceutical formulations. In this research, gelatin and its combinations with sucrose oleate as a small molecular emulsifier, sodium caseinate (SC) as a protein and gum Arabic as a polysaccharide were used as stabilizer systems in the formation of astaxanthin nanodispersions via an emulsification-evaporation process. The results indicated that the addition of SC to gelatin in the stabilizer system could increase the chemical stability of astaxanthin nanodispersions significantly, while using a mixture of gelatin and sucrose oleate as a stabilizer led to production of nanodispersions with the smallest particle size (121.4±8.6 nm). It was also shown that a combination of gelatin and gum Arabic could produce optimal astaxanthin nanodispersions in terms of physical stability (minimum polydispersity index (PDI) and maximum zeta-potential). This study demonstrated that the mixture of surface active compounds showed higher emulsifying and stabilizing functionality compared to using them individually in the preparation of astaxanthin nanodispersions.
    Matched MeSH terms: Particle Size
  14. Development and evaluation of omeprazole pellets fabricated by sieving-spheronization and extrusion - spheronization process
    Karim S, Baie SH, Hay YK, Bukhari NI
    Pak J Pharm Sci, 2014 May;27(3):425-38.
    PMID: 24811797
    Pelletized dosage forms can be prepared by different methods which, in general, are time consuming and labor intensive. The current study was carried out to investigate the feasibility of preparing the spherical pellets of omeprazole by sieving-spheronization. An optimized formulation was also prepared by extrusion-spheronization process to compare the physical parameters between these two methods. The omeprazole pellets were consisted of microcrystalline cellulose, polyvinylpyrrolidone K 30, sodium lauryl sulphate and polyethylene glycol 6000. The omeprazole delay release system was developed by coating the prepared pellets with aqueous dispersion of Kollicoat 30 DP. The moisture content, spheronization speed and residence time found to influence the final properties of omeprazole pellets prepared by extrusion-spheronization and sieving-spheronization. The Mann-Whitney test revealed that both methods produced closely similar characteristics of the pellets in terms of, friability (p=0.553), flowability (p=0.677), hardness (p=0.103) and density (bulk, p=0.514, tapped, p=0.149) except particle size distribution (p=0.004). The percent drug release from the coated formulation prepared by sieving-spheronization and extrusion spheronization was observed to be 84.12 ± 1.10% and 82.67 ± 0.96%, respectively. Dissolution profiles of both formulations were similar as indicated by values of f1 and f2, 1.52 and 89.38, respectively. The coated formulation prepared by sieving-spheronization and commercial reference product, Zimore ® also showed similar dissolution profiles (f1=1.22, f2=91.52). The pellets could be prepared using sieving-spheronization. The process is simple, easy, less time- and labor-consuming and economical as compared to extrusion-spheronization process.
    Matched MeSH terms: Particle Size
  15. Is metal nanofluid reliable as heat carrier?
    Nine MJ, Chung H, Tanshen MR, Osman NA, Jeong H
    J Hazard Mater, 2014 May 30;273:183-91.
    PMID: 24735805 DOI: 10.1016/j.jhazmat.2014.03.055
    A pre- and post experimental analysis of copper-water and silver-water nanofluids are conducted to investigate minimal changes in quality of nanofluids before and after an effective heat transfer. A single loop oscillating heat pipe (OHP) having inner diameter of 2.4mm is charged with aforementioned nanofluids at 60% filling ratio for end to end heat transfer. Post experimental analysis of both nanofluids raises questions to the physical, chemical and thermal stability of such suspension for hazardless uses in the field of heat transfer. The color, deposition, dispersibility, propensity to be oxidized, disintegration, agglomeration and thermal conductivity of metal nanofluids are found to be strictly affected by heat transfer process and vice versa. Such degradation in quality of basic properties of metal nanofluids implies its challenges in practical application even for short-term heat transfer operations at oxidative environment as nano-sized metal particles are chemically more unstable than its bulk material. The use of the solid/liquid suspension containing metal nanoparticles in any heat exchanger as heat carrier might be detrimental to the whole system.
    Matched MeSH terms: Particle Size
  16. Fulltext Modified smoothed particle hydrodynamics (MSPH) for the analysis of centrifugally assisted TiC-Fe-Al2O3 combustion synthesis
    Hassan MA, Mahmoodian R, Hamdi M
    Sci Rep, 2014;4:3724.
    PMID: 24430621 DOI: 10.1038/srep03724
    A modified smoothed particle hydrodynamic (MSPH) computational technique was utilized to simulate molten particle motion and infiltration speed on multi-scale analysis levels. The radial velocity and velocity gradient of molten alumina, iron infiltration in the TiC product and solidification rate, were predicted during centrifugal self-propagating high-temperature synthesis (SHS) simulation, which assisted the coating process by MSPH. The effects of particle size and temperature on infiltration and solidification of iron and alumina were mainly investigated. The obtained results were validated with experimental microstructure evidence. The simulation model successfully describes the magnitude of iron and alumina diffusion in a centrifugal thermite SHS and Ti + C hybrid reaction under centrifugal acceleration.
    Matched MeSH terms: Particle Size
  17. Fulltext Investigation of vortex clouds and droplet sizes in heated water spray patterns generated by axisymmetric full cone nozzles
    Naz MY, Sulaiman SA, Ariwahjoedi B, Ku Shaari KZ
    ScientificWorldJournal, 2013;2013:796081.
    PMID: 24307881 DOI: 10.1155/2013/796081
    The hot water sprays are an important part of many industrial processes, where the detailed knowledge of physical phenomena involved in jet transportation, interaction, secondary breakup, evaporation, and coalescence of droplets is important to reach more efficient processes. The objective of the work was to study the water spray jet breakup dynamics, vortex cloud formation, and droplet size distribution under varying temperature and load pressure. Using a high speed camera, the spray patterns generated by axisymmetric full cone nozzles were visualized as a function water temperature and load pressure. The image analysis confirmed that the spray cone angle and width do not vary significantly with increasing Reynolds and Weber numbers at early injection phases leading to increased macroscopic spray propagation. The formation and decay of semitorus like vortex clouds were also noticed in spray structures generated at near water boiling point temperature. For the nozzle with smallest orifice diameter (1.19 mm), these vortex clouds were very clear at 90°C heating temperature and 1 bar water load pressure. In addition, the sauter mean diameter (SMD) of the spray droplets was also measured by using Phase Doppler Anemometry (PDA) at different locations downstream of the nozzle exit. It was noticed that SMD varies slightly w.r.t. position when measured at room temperature whereas at higher temperature values, it became almost constant at distance of 55 mm downstream of the nozzle exit.
    Matched MeSH terms: Particle Size
  18. Preparation of emulsions by rotor-stator homogenizer and ultrasonic cavitation for the cosmeceutical industry
    Han NS, Basri M, Abd Rahman MB, Abd Rahman RN, Salleh AB, Ismail Z
    J Cosmet Sci, 2012 Sep-Oct;63(5):333-44.
    PMID: 23089355
    Oil-in-water (O/W) nanoemulsions play an important key role in transporting bioactive compounds into a range of cosmeceutical products to the skin. Small droplet sizes have an inherent stability against creaming, sedimentation, flocculation, and coalescence. O/W emulsions varying in manufacturing process were prepared. The preparation and characterization of O/W nanoemulsions with average diameters of as low as 62.99 nm from palm oil esters were carried out. This was achieved using rotor-stator homogenizer and ultrasonic cavitation. Ultrasonic cell was utilized for the emulsification of palm oil esters and water in the presence of mixed surfactants, Tween 80 and Span 80 emulsions with a mean droplet size of 62.99 nm and zeta potential value at -37.8 mV. Results were comparable with emulsions prepared with rotor-stator homogenizer operated at 6000 rpm for 5 min. The stability of the emulsions was evaluated through rheology measurement properties. This included non-Newtonian viscosity, elastic modulus G', and loss modulus G″. A highly stable emulsion was prepared using ultrasonic cavitation comprising a very small particle size with higher zeta potential value and G' > G″ demonstrating gel-like behavior.
    Matched MeSH terms: Particle Size
  19. Effects of oil and drug concentrations on droplets size of palm oil esters (POEs) nanoemulsion
    Sakeena MH, Elrashid SM, Munavvar AS, Azmin MN
    J Oleo Sci, 2011;60(4):155-8.
    PMID: 21427510
    Aim of the present work is to study the effects of oil and drug concentrations on droplets size of a nanoemulsion. Newly introduced oil, palm oil esters (POEs) by Universiti Putra Malaysia researchers was selected for the oil phase of the nanoemulsion, because the oil was reported to be a good vehicle for pharmaceutical use. Nanoemulsions were prepared with different concentrations of oil and drug and their effects on droplets size were studied by laser scattering spectroscopy (Nanophox). The results of droplets size analysis shows the droplets size increase with increasing concentration of oil and drug concentrations. It can be concluded from this study, that oil and drug concentrations have an effect on the droplets size of POEs nanoemulsion system.
    Matched MeSH terms: Particle Size
  20. Physicochemical characterization of natural-like branched-chain glycosides toward formation of hexosomes and vesicles
    Ahmad N, Ramsch R, Esquena J, Solans C, Tajuddin HA, Hashim R
    Langmuir, 2012 Feb 7;28(5):2395-403.
    PMID: 22168405 DOI: 10.1021/la203736b
    Synthetic branched-chain glycolipids have become of great interest in biomimicking research, since they provide a suitable alternative for natural glycolipids, which are difficult to extract from natural resources. Therefore, branched-chain glycolipids obtained by direct syntheses are of utmost interest. In this work, two new branched-chain glycolipids are presented, namely, 2-hexyldecyl β(α)-D-glucoside (2-HDG) and 2-hexyldecyl β(α)-D-maltoside (2-HDM) based on glucose and maltose, respectively. The self-assembly properties of these glycolipids have been studied, observing the phase behavior under thermotropic and lyotropic conditions. Due to their amphiphilic characteristics, 2-HDG and 2-HDM possess rich phase behavior in dry form and in aqueous dispersions. In the thermotropic study, 2-HDG formed a columnar hexagonal liquid crystalline phase, whereas in a binary aqueous system, 2-HDG formed an inverted hexagonal liquid crystalline phase in equilibrium with excess aqueous solution. Furthermore, aqueous dispersions of the hexagonal liquid crystal could be obtained, dispersions known as hexosomes. On the other hand, 2-HDM formed a lamellar liquid crystalline phase (smectic A) in thermotropic conditions, whereas multilamellar vesicles have been observed in equilibrium with aqueous media. Surprisingly, 2-HDM mixed with sodium dodecyl sulfate or aerosol OT induced the formation of more stable unilamellar vesicles. Thus, the branched-chain glycolipids 2-HDG and 2-HDM not only provided alternative nonionic surfactants with rich phase behavior and versatile nanostructures, but also could be used as new drug carrier systems in the future.
    Matched MeSH terms: Particle Size
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