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Possible intermolecular association in triphenyltin chloride in the solution state as detected by NMR spectroscopy

Ng S, Sathasivam RV, Lo KM

Magn Reson Chem, 2011 Nov;49(11):749-52.
PMID: 22002760 DOI: 10.1002/mrc.2827

NMR measurements ((119)Sn chemical shift, line width and (13)C relaxation) were made on triphenyltin chloride in two solutions, 2.5 and 0.75 mol% in CDCl(3), at several temperatures. The (13)C spin-lattice relaxation time and NOE data for the phenyl carbons provide the corresponding correlation times for the overall molecular reorientational motion and the internal rotation of the phenyl groups. The results are indicative of a weak intermolecular association of the triphenyltin chloride molecules in solution and are discussed with reference to a model for intermolecular phenyl ring π-π stacking interactions.

Matched MeSH terms: Solutions
Fulltext Easy lens cleaning solution for laboratory microscopes

Pramanik T, Ghosh A, Roychowdhury P

Med J Malaysia, 2005 Mar;60(1):116.
PMID: 16250297
Matched MeSH terms: Solutions
Optical Properties of Azo-Benzothiazole Side Chain Liquid Crystalline Polymers: Effect of Solvents, Substituents and Temperatures

Dzulkharnien NSF, Karim MR, Zahid NI, Rahman NMMA, Abdullah I, Salleh NM

J Fluoresc, 2019 Jul;29(4):1049-1056.
PMID: 31338718 DOI: 10.1007/s10895-019-02418-9

The optical properties of a series of side chain liquid crystalline polymers (P1-P3) containing azo-benzothiazole mesogen with different terminal substituents (-H, -CH3 and -OCH2CH3) in four organic solvents of varying polarity have been investigated by absorption and fluorescence spectral analysis. Solvatochromic studies of P1-P3 did not show any regular variation on the absorption and emission intensities with changing the polarity of solvent. Theoretical studies were performed based on different solvent correlation methods such as Dimroth-Reichardt and Kamlet-Taft methods to investigate the solute-solvent interactions. Both absorption and emission maxima of investigated polymers were bathochromically shifted with the replacement of sixth position hydrogen atom by electron donating groups in benzothiazole moiety. The emission intensities of the studied polymers showed decreasing trend with increasing temperature.

Matched MeSH terms: Solutions
Fulltext Dehiscence Treated With Non-Resorbable Gore-Tex Membrane - A Case Report

Kamin, S., Ghani, S.H.A.

Ann Dent, 1996;3(1):-.
MyJurnal

Severe gingival recession caused by dehiscence usually present a challenging task to the clinician as any mucogingival surgery without bony regeneration will not 'prevent the condition from recurring. The procedures of guided tissue regeneration ( GTR ) which allow regeneration of the lost periodontium may offer some solution to the condition. This paper reports on the use of a non-resorbable GTR membrane to treat an isolated lower incisor gingival recession associated with dehiscence.

Matched MeSH terms: Pharmaceutical Solutions
Fulltext Ionic conductivity of MG30-PEMA blend solid polymer electrolyte

Ayub, S.F., Nazir, K., Aziz, A.F., Ali, A.M.M., Saaid, S.I.Y., Yahya, M.Z.A.

Scientific Research Journal, 2015;12(2):0-0.
MyJurnal

This paper presents on ionic conductivity of MG30-PEMA blend solid polymer electrolytes (SPEs) prepared by solution cast technique. The analysis has shown that conductivity increases with the increasing salt composition. It is observed via x-ray diffraction analysis that the crystallinity of the sample decreased with the amount of salt composition as expected. It is also observed that the dielectric value increases with increasing amount of LiCF3SO3 in the sample. Surface morphology revealed that ion aggregation occurred after optimum conductivity which has lowered the conductivity.

Matched MeSH terms: Pharmaceutical Solutions
Fulltext Theoretical modeling of pseudo hydrostatic force in solid-liquid pipe flow with two layer

Hussain H. Al-Kayiem, Iylia Elena Abdul Jamil

Pertanika Journal of Science & Technology, 2013;21(2):521-532.
MyJurnal

In the moving layer of particles with variable concentration, the shear estimation is not directly predictable and there is no existing clear mathematical or empirical formula to achieve this objective. This paper presents a developed approach to estimate the shear forces in a flow having suspended and moving layers of solid particles in liquid flow. The two-layer approach was taken whereby the flow consisting of one upper suspended layer of particles in the liquid, and the bottom layer was the moving bed of particles. In the present work, the method of finding the force acting on the pipe wall by the particles in the layer, termed as the ‘dry force’, was presented using a “pseudo hydrostatic pressure” method. To attain the equation for the dry force, a mathematical approach is taken with the assumptions that the flow is horizontal, two-phase pipe flow (solid in Newtonian liquid), incompressible and it is at steady-state. The analysis was conducted considering various particles densities, various concentrations in the suspended layer and different thicknesses of the moving bed. Changing the concentration in the suspended layer from 0.00001 up to 0.001 didn’t showed significant changes in the dry force evaluation. The dry friction force is increasing with increasing moving bed thickness. The developed mathematical model can be
applicable in solving for the shear force in horizontal solid liquid two-phase flows.

Matched MeSH terms: Pharmaceutical Solutions
Fulltext Enzymatic rettings of green pepper berries for white pepper production

Rosnah, S., Chan, S.C.

International Food Research Journal, 2014;21(1):237-245.
MyJurnal

This study is carried out to determine the physical properties of green pepper berries and to
improve the existing retting technique in white pepper production using the Viscozyme and
Celluclast as the enzymes. Effects of blanched and non-blanched pepper berries, acidic solution
and non-acidic solution, and different temperature of 28, 35, 42, and 49°C are determined to
obtain the optimum conditions for enzymatic retting. The physical properties of green pepper
berries such as dimension (5.21 mm), weight (0.11 g per berry), true density (1319.33 kg/m3),
bulk density (596.9 kg/m3), sphericity (0.976), angle of repose (6.87°) and flow ability with
funnel flow time of 5.27 seconds were determined. The enzymatic retting in 42oC can fully
soften the pericarp of pepper berries from 15 days to 7 days. The enzymatic decortication has
the efficiency in acidic solution (pH 4) and temperature of 42°C with non-blanched pepper
berries. The enzymatic retting reached constant fracture force (20.98N) at the ninth soaking
days while the non-enzymatic retting reached constant fracture force (21.89N) at the fifteenth
soaking days.

Matched MeSH terms: Pharmaceutical Solutions
Structural and Electrical Characterization of SiO2 Gate Dielectrics Deposited from Solutions at Moderate Temperatures in Air

Esro M, Kolosov O, Jones PJ, Milne WI, Adamopoulos G

ACS Appl Mater Interfaces, 2017 01 11;9(1):529-536.
PMID: 27933760 DOI: 10.1021/acsami.6b11214

Silicon dioxide (SiO2) is the most widely used dielectric for electronic applications. It is usually produced by thermal oxidation of silicon or by using a wide range of vacuum-based techniques. By default, the growth of SiO2 by thermal oxidation of silicon requires the use of Si substrates whereas the other deposition techniques either produce low quality or poor interface material and mostly require high deposition or annealing temperatures. Recent investigations therefore have focused on the development of alternative deposition paradigms based on solutions. Here, we report the deposition of SiO2 thin film dielectrics deposited by spray pyrolysis in air at moderate temperatures of ≈350 °C from pentane-2,4-dione solutions of SiCl4. SiO2 dielectrics were investigated by means of UV-vis absorption spectroscopy, spectroscopic ellipsometry, XPS, XRD, UFM/AFM, admittance spectroscopy, and field-effect measurements. Data analysis reveals smooth (RRMS < 1 nm) amorphous films with a dielectric constant of about 3.8, an optical band gap of ≈8.1 eV, leakage current densities in the order of ≈10(-7) A/cm(2) at 1 MV/cm, and high dielectric strength in excess of 5 MV/cm. XPS measurements confirm the SiO2 stoichiometry and FTIR spectra reveal features related to SiO2 only. Thin film transistors implementing spray-coated SiO2 gate dielectrics and C60 and pentacene semiconducting channels exhibit excellent transport characteristics, i.e., negligible hysteresis, low leakage currents, high on/off current modulation ratio on the order of 10(6), and high carrier mobility.

Matched MeSH terms: Solutions
Fulltext Adsorption and desorption study of ¹⁴C-chlorpyrifos in two Malaysian agricultural soils

Halimah Muhamad, Nashriyah Mat, Tan, Yew Ai, Ismail, B.S.

Journal of Nuclear and Related Technologies, 2004;2004(1):23-33.
MyJurnal

The adsorption equilibrium time and effects of pH and concentration of ¹⁴C-labeled chlorpyrifos
O,O-diethyl O-(3, 5, 6 trichloro-2-pyridyl)-phosphorothiote in soil were investigated. Two types of Malaysian soil under oil palm were used in this study; namely clay loam and clay soil obtained from the Sungai Sedu and Kuala Lumpur International Airport (KLIA) Estates, respectively. Equilibrium studies of chlorpyrifos between the agricultural soil and the pesticide solution were conducted. Adsorption equilibrium time was achieved within 6 and 24 hours for clay loam and clay soil, respectively. It was found that chlorpyrifos adsorbed by the soil samples was characterized by an initial rapid adsorption after which adsorption remained approximately constant. The percentage of ¹⁴C-labeled chlorpyrifos adsorption on soil was found to be higher in clay loam than in clay soils. Results of the study demonstrated that pH affected the adsorption of chlorpyrifos on both clay loam and clay soils. The adsorption of chlorpyrifos on both types of soil was higher at low pH with the adsorption reduced as the pH increased. Results also suggest that chlorpyrifos sorption by soil is concentration dependent.

Matched MeSH terms: Pharmaceutical Solutions
Fulltext Numerical modelling of molten carbonate fuel cell: effects of gas flow direction in anode and cathode

Tay C. L., Law M. C.

Pertanika Journal of Science & Technology, 2014;22(2):645-655.
MyJurnal

The modelling of a three-dimensional (3-D) molten carbonate fuel cell (MCFC) was developed to study the effects of gas flow direction (co-flow and counter-flow) in anode and cathode on the generated power density by solving the mass and momentum conservation equations, electrochemical reaction and heat transfer. The simulation result of the co-flow temperature distribution was compared with the experimental data obtained from open literature. The molar fraction distribution of gases in the anode and cathode gas channels and temperature distribution across the cell were compared between two different flow directions. Furthermore, the performance of MCFC, which operates in the temperature range of 823 - 1023 K, was analysed by comparing the generated power density. The results showed that MCFC with co-flow attained higher power density compared to that of counter-flow at 873 K. However, at higher temperature of 1023 K, the generated power density was the same for both gas flow directions.

Matched MeSH terms: Pharmaceutical Solutions
Fulltext Prediction of β-carotene solubility at supercritical conditions using regular solutions theory

Kassim, K.M., Davarnejad, R.

ASM Science Journal, 2007;1(2):143-154.
MyJurnal

The objective of this paper is to model the extraction of carotenoid with supercritical carbon dioxide as the solvent. Experimental data for the high pressure vapour-liquid phase equilibrium of the binary system carbon dioxide-carotenoid was reviewed for the elevated temperatures of 313.15, 323.15, 333.15 K and pressures up to 500 bar. The experimental data was correlated and modeled using Redlich-Kwong equation of state and regular solution methods. The use of the equation of state as an empirical correlation for collating and predicting liquid-liquid and liquid-dense fluid equilibria is discussed. It was concluded that the estimation of some of the parameters required for these calculations would be difficult if the solute (carotenoid) was a complex substance about which little was known apart from its structural formula. An alternative procedure is to apply activity coefficient expression of the regular solution theory type to each phase. Calculations along these lines are described and the physical basis for applying these methods under the relevant conditions is discussed. The regular solution theory approach in particular was found to be encouraging for the mutual miscibility calculations for heavy components (such as carotenoid) particularly for substances sensitive to temperature, though the interaction parameters for he prediction activity coefficients must be regarded as pressure dependent.

Matched MeSH terms: Pharmaceutical Solutions
Fulltext The effect of fibre alignment, fibre treatment and pre-irradiation on the mechanical and environmental properties of kenaf-reinforced polypropylene composites

Sharifah Hanisah S.A. Aziz, Khairul Zaman Mohd Dahlan, Jalaluddin Harun

Journal of Nuclear and Related Technologies, 2008;2008(1):33-44.
MyJurnal

At present, research in composite materials is being directed at using natural fibres instead of synthetic fibres. Kenaf which is extensively grown in the Far East including Malaysia, has been identified as a bast (stem) fibre with significant market potential. In this work, long and random kenaf fibres (non-woven mat form) were used in the as-received condition and alkalized with a 0.06M NaOH solution. They were combined with polypropylene thin sheets, sandwiched between layers of kenaf fibres and hot-pressed to form natural fibre composites. The mechanical properties of the composites were investigated to observe the effect of fibre alignment, fibre treatment and pre-irradiation method used. A general trend was observed whereby alkalized and long fibre composites gave higher flexural modulus and flexural strength compared with random mat and untreated fibres. The long fibre composites also gave a higher work of fracture. However, the correlation between fibre surface treatment and the work of fracture was less clear. Pre-irradiation on the polypropylene pellets and fibres before the composite is manufactured showed significant improvement on the flexural modulus and flexural strength. The bond performance test performed on the treated composites demonstrated good bonding and interfacial adhesion between the fibre and matrix. However, the method of moulding used need to be improved to optimize the performance of the composites.

Matched MeSH terms: Pharmaceutical Solutions
Fulltext Optimization of the cytogenetic protocol for Pangasianodon hypophthalmus (Sauvage, 1878) and Clarias gariepinus (Burchell, 1822)

Okomoda VT, Koh ICC, Hassan A, Amornsakun T, Moh JHZ, Shahreza SM

PeerJ, 2018;6:e5712.
PMID: 30416879 DOI: 10.7717/peerj.5712

To obtain well spread chromosomes, the cytogenetic protocol for Pangasianodon hypophthalmus and Clarias gariepinus were optimized. This includes, the colchicine concentration (0.01%, 0.025%, 0.05%)/exposure duration (1, 3, and 5 h), hypotonic solution (distilled water or 0.075M KCl solution)/exposure duration (30 min, 1, and 2 h), the time of cell suspension preparation (at hypotonic treatment or before slide preparation) and chromosome aging period (0, 3, and 7 days in Carnoy's fixative). In addition, the type (i.e., fin, gill or kidney) and the amount of tissue (10, 50, 100 or 150 mg) were also investigated. Regardless of the species, the result obtained showed that well-spread chromosomes could be obtained using the following optimized protocol: Juveniles are injected with 0.05% colchicine (at one ml kg-1) and allowed to swim for 3 h. Then, 50 mg of gill tissue is made into cell suspension in 0.075M KCl for 1 h. The cell suspension is treated in Carnoy's fixative (changed three times at 20 min interval) and then aged for 3 days. Finally, chromosome slides are made and stained with 10% Giemsa for 1 h.

Matched MeSH terms: Hypotonic Solutions
Fulltext Physicochemical properties of canola oil, olive oil and palm olein blends

Roiaini, M., Ardiannie, T., Norhayai, H.

International Food Research Journal, 2015;22(3):1227-1233.
MyJurnal

Oil blending has been recognized as one of the most potent solution in producing vegetable oils with good storage stabilities and optimum fatty acids compositions. This study was conducted to identify the best oil blends in terms of physicochemical properties between canola, olive and palm olein oil. Canola and olive oils were blended at different ratios of 80:20, 60:40, 50:50, 40:60, and 20:80. Palm olein is stable against rancidity and oxidation thus the above blends were mixed with 20% palm olein. The 80:20 canola: olive blend shows the best properties after being mixed with 20% palm olein compared to other blends. It passed the cold stability test and has significantly the lowest cloud point of 6.0oC (p

Matched MeSH terms: Pharmaceutical Solutions
Eye drop instillation technique among patients with glaucoma and evaluation of pharmacists' roles in improving their technique: an exploratory study

Kan YM, Kho BP, Kong L, Chong QX, Tiong MNJ, Wong LMJ

Int J Pharm Pract, 2022 Dec 31;30(6):520-525.
PMID: 35942810 DOI: 10.1093/ijpp/riac063

OBJECTIVES: This study aimed to explore the eye drop instillation technique of patients with glaucoma and whether a pharmacist-led counselling session can improve their technique. Patients' perceptions of pharmacists' role in providing the counselling were also explored.
METHODS: This cross-sectional study was conducted between December 2020 and March 2021 at Sarawak General Hospital, Malaysia. Convenience sampling was used to recruit patients with glaucoma who self-administered their eye drops. Participants' background information were obtained using an investigator-administered questionnaire before their eye drop instillation technique was assessed. Those with imperfect techniques were counselled by a pharmacist before being reassessed. Differences in eye drop instillation competency were determined using paired T-test.
KEY FINDINGS: A total of 138 participants were recruited. Participants were on a median of two eye drops (IQR 2-4) for a median of five years (IQR 2-8). Prior to being counselled, they demonstrated a mean total of 8.4/13 steps (SD 2.33) correctly. A statistically significant improvement in eye drop instillation technique was observed post-pharmacists' counselling, with a mean increase of 4.3 steps demonstrated correctly (95% CI, 4.0 to 4.7, P < 0.001). The majority of participants agreed that pharmacists are knowledgeable in providing counselling on eye drop administration techniques.
CONCLUSIONS: Patients with glaucoma treated at Sarawak General Hospital had imperfect eye drop instillation techniques, despite most having used their eye drops for several years. Interventions by pharmacists to improve eye drop instillation are crucial to optimise the medical treatment of patients with glaucoma.

Matched MeSH terms: Ophthalmic Solutions
Do colloids in comparison to crystalloids for fluid resuscitation improve mortality?

Naing CM, Win DK

Trans R Soc Trop Med Hyg, 2010 May;104(5):311-2.
PMID: 20206954 DOI: 10.1016/j.trstmh.2010.02.001

Permanent neurological impairment or death arising from hospital-acquired hyponatremia in both children and adults is well documented. The choice of intravenous fluids for fluid resuscitation in critically ill patients is a top priority in evidence-based medicine. The question of whether colloids in comparison to crystalloids can improve mortality in such cases remains to be answered. Well powered, randomized clinical trials addressing the comparative efficacy of different types of intravenous fluids is a high priority as is the ethical justification for such trials. The understanding of the pathophysiological process serves important information on clinical practice.

Matched MeSH terms: Isotonic Solutions/adverse effects; Isotonic Solutions/therapeutic use*
Clinical utility of caspofungin eye drops in fungal keratitis

Neoh CF, Daniell M, Chen SC, Stewart K, Kong DC

Int J Antimicrob Agents, 2014 Aug;44(2):96-104.
PMID: 24933448 DOI: 10.1016/j.ijantimicag.2014.04.008

Treatment of fungal keratitis remains challenging. To date, only the polyenes and azoles are commonly used topically in the management of fungal keratitis. Natamycin, a polyene, is the only antifungal eye drop that is commercially available; the remainder are prepared in-house and are used in an 'off-label' manner. Failure of medical treatment for fungal keratitis is common, hence there is a need for more effective topical antifungal therapy. To increase the antifungal eye drop armamentarium, it is important to investigate the utility of other classes of antifungal agents for topical use. Caspofungin, an echinocandin antifungal agent, could potentially be used to address the existing shortcomings. However, little is known about the usefulness of topically administered caspofungin. This review will briefly explore the incidence, epidemiology and antifungal treatment of fungal keratitis. It will focus primarily on evidence related to the efficacy, safety and practicality of using caspofungin eye drops in fungal keratitis.

Matched MeSH terms: Ophthalmic Solutions/adverse effects; Ophthalmic Solutions/therapeutic use
Fulltext Closed form solutions for unsteady free convection flow of a second grade fluid over an oscillating vertical plate

Ali F, Khan I, Shafie S

PLoS One, 2014;9(2):e85099.
PMID: 24551033 DOI: 10.1371/journal.pone.0085099

Closed form solutions for unsteady free convection flows of a second grade fluid near an isothermal vertical plate oscillating in its plane using the Laplace transform technique are established. Expressions for velocity and temperature are obtained and displayed graphically for different values of Prandtl number Pr, thermal Grashof number Gr, viscoelastic parameter α, phase angle ωτ and time τ. Numerical values of skin friction τ 0 and Nusselt number Nu are shown in tables. Some well-known solutions in literature are reduced as the limiting cases of the present solutions.

Matched MeSH terms: Solutions
Catalytic cracking of bio-oil to organic liquid product (OLP)

Hew KL, Tamidi AM, Yusup S, Lee KT, Ahmad MM

Bioresour Technol, 2010 Nov;101(22):8855-8.
PMID: 20621470 DOI: 10.1016/j.biortech.2010.05.036

The main objective of this paper is to find the optimum operating condition to upgrade the EFB-derived pyrolysis oil (bio-oil) to liquid fuel, mainly gasoline using Taguchi Method. From the analysis that has been done, it is found that the optimum operating condition for heterogeneous catalytic cracking process is at 400 degrees C, 15min of reaction time using 30g of catalyst weight where operating at this condition produced the highest yield of gasoline fraction which is 91.67 wt.%. This observation proves that EFB-derived pyrolysis oil could be upgraded via heterogeneous catalytic cracking to produce gasoline.

Matched MeSH terms: Solutions
Kinetic adsorption of application of carbon nanotubes for Pb(II) removal from aqueous solution

Kabbashi NA, Atieh MA, Al-Mamun A, Mirghami ME, Alam MD, Yahya N

J Environ Sci (China), 2009;21(4):539-44.
PMID: 19634432

The capability of carbon nanotubes (CNTs) to adsorb lead (Pb) in aqueous solution was investigated. Batch mode adsorption experiment was conducted to determine the effects of pH, agitation speed, CNTs dosage and contact time. The removal of Pb(II) reached maximum value 85% or 83% at pH 5 or 40 mg/L of CNTs, respectively. Higher correlation coefficients from Langmuir isotherm model indicates the strong adsorptions of Pb(II) on the surface of CNTs (adsorption capacity Xm = 102.04 mg/g). The results indicates that the highest percentage removal of Pb (96.03%) can be achieved at pH 5, 40 mg/L of CNTs, contact time 80 min, and agitation speed 50 r/min.

Matched MeSH terms: Solutions

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