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Evaluation of diuretic potential of Nephrolepis cordifolia rhizome juice in wistar rats

Rajasekaran A, Sivakumar V

Sains Malaysiana, 2009;38.

Nephrolepis cordifolia rhizome (sword fern) juice was investigated for diuretic activity in wistar rats. Different parameters viz. total urine volume (corrected for water intake during the test period), urine concentration of electrolytes such as sodium, potassium and chloride have been evaluated. Rhizome juice of Nephrolepis cordifolia (100 mg/kg), the reference drug, furosemide (20 mg/kg) was administrated orally to male Wistar rats and their urine output was quantitated at several intervals of time after the dose. After single dose of the rhizome juice of Nephrolepis cordifolia, urine output was significantly increased. Increase in urinary levels of Na+, K+ and Cl- was also observed after the administration of rhizome juice.

Matched MeSH terms: Chlorides
Impact of molecular structure, headgroup and alkyl chain geometry, on the adsorption of the anionic ester sulfonate surfactants at the air-solution interface, in the presence and absence of electrolyte

Wang Z, Li P, Ma K, Chen Y, Campana M, Penfold J, et al.

J Colloid Interface Sci, 2019 May 15;544:293-302.
PMID: 30861434 DOI: 10.1016/j.jcis.2019.03.011

The transition from monolayer to multilayer adsorption at the air-water interface in the presence of multivalent counterions has been demonstrated for a limited range of anionic surfactants which exhibit increased tolerance to precipitation in the presence of multivalent counterions. Understanding the role of molecular structure in determining the transition to surface ordering is an important aspect of the phenomenon. The focus of the paper is on the alkyl ester sulfonate, AES, surfactants; a promising group of anionic surfactants, with the potential for improved performance and biocompatibility. Neutron reflectivity measurements were made in aqueous solution and in the presence of NaCl, CaCl2, MgCl2 and AlCl3, for a range of alkyl ester sulfonate surfactants, in which the headgroup and alkyl chain geometries were manipulated. In the regions of monolayer adsorption changing the AES headgroup and alkyl chain geometries results in an increased saturation adsorption and in a more gradual decrease in the adsorption at low concentrations, consistent with a greater adsorption efficiency. Changing the AES headgroup and alkyl chain geometries also results in changes in the transition from monolayer adsorption to more ordered surface structures with the addition of AlCl3 and mixed multivalent electrolytes. A more limited surface layering is observed for the ethyl ester sulfonate, EES, with a C14 alkyl chain. Replacing the C14 alkyl chain with a C18 isostearic chain results in only monolayer adsorption. The results demonstrate the role and importance of the surfactant molecular structure in determining the nature of the surface adsorption in the presence of different electrolytes, and in the tendency to form extended surface multilayer structures.

Matched MeSH terms: Chlorides
Fulltext Physico-mechanical properties and formaldehyde emission of rubberwood particleboard made with UF resin admixed with ammonium and aluminium-based hardeners

Abd Ghani Aizat, Paiman, Bawon, Lee, Seng Hua, Ashaari Zaidon

Pertanika Journal of Science & Technology, 2019;27(1):473-488.
MyJurnal

In this study, the effects of addition of ammonium and aluminium-based hardeners into
urea formaldehyde resin (UF) on the physico-mechanical properties and formaldehyde
emission of the rubberwood particleboard were investigated. Four types of hardeners,
namely ammonium chloride (AC), ammonium sulphate (AS), aluminium chloride (AlC)
and aluminium sulphate (AlS), were added into UF resin. The acidity, gelation time,
viscosity and free formaldehyde content of the UF/hardener mixtures were determined.
Particleboard made with the UF/hardener mixtures were tested for physico-mechanical
properties and formaldehyde emission. The pH values of the resin after addition of
aluminium-based hardeners were higher and resulted in higher viscosity and shorter
gelation time. Consequently, despite lower formaldehyde emission was recorded, the
physico-mechanical properties of the resulted particleboard were inferior compared to
that of ammonium-based hardeners. The best quality particleboard in terms of mechanical,
physical and formaldehyde emission were obtained from the particleboard made with AS,
followed by AC.

Matched MeSH terms: Chlorides
Fulltext Functional diversity of biocatalysts: whether to bioprospect or bioengineer?

Benbelgacem, Farah Fadwa, Bellag, Oualid Abdelkader, Soroodi, Fatemeh, Abdul Aziz Ahmad, Hamzah Mohd Salleh, Noorbatcha, Ibrahim Ali

Biological and Natural Resources Engineering Journal, 2019;2(1):64-84.
MyJurnal

Biocatalyst should have sufficient and efficient activity for the intended
biotechnological application. In the quest for novel biocatalyst, there is a need to have a
genetic diversity either by finding it within the astronomically large number of possible
candidates or to obtain it by bioengineering an existing gene supported by various
bioinformatic and molecular engineering tools. Nowadays, it is well-known that a huge
number of microorganisms is unculturable and poses great challenges to access biocatalysts
from these microbes. Metagenomics is one of the methods widely applied to reach out
maximum possible variants to “bioprospect” biocatalysts. On the other hand, other approaches
are available to bioengineer enzymes by modifying the DNA sequence precisely based on the
structure and the function information of the protein in the case of rational design, or by a
brave creation of anarchic mutations of the DNA sequence with directed evolution method. In
this regard, both approaches, whether to bioprospect or to bioengineer biocatalysts have
advantages and disadvantages which will be discussed in this paper.KEY WORDS: Sugar
industry wastewater; aluminium sulphate; primary treatment, ferric chloride; polyaluminium
chloride

Matched MeSH terms: Chlorides
Fulltext Biosynthesis of nanoparticles using recombinant bromelain

Arina Nasruddin, Azura Amid, Muhd Ezza Faiez Othman

Biological and Natural Resources Engineering Journal, 2018;1(1):14-25.
MyJurnal

Green chemical method was applied to synthesize nanoparticles using recombinant
bromelain. Among the numerous applications of recombinant bromelain, there is still no research
on nanoparticles synthesis which encourages its utilization in this study. Four chemicals which are
copper (II) chloride dihydrate (CuCl2.2H2O), cerium nitrate hexahydrate (Ce(NO3)3.6H2O), sodium
selenite (Na2SeO3), and iron (III) chloride hexahydrate (FeCl3.6H2O) were selected to be screened
for the suitability in nanoparticles biosynthesis by recombinant bromelain. The nanoparticles
formed were characterized by using UV-visible absorption spectra. The biosynthesis process then
was optimized by varying the centrifugation speed, temperature, and time to get the maximum
absorption and weight of nanoparticles through central composite design (CCD) tool. Only
CuCl2.2H2O showed a positive result for the screening process which was represented by the
formation of colloidal solution and a maximum absorption at 580 nm. Thus, optimization was
carried out for this chemical. Based on the optimization model, maximum absorption and weight
were predicted at 67.5°C, 2 hrs, and 9,600 rpm. These optimal conditions were validated by
repeating the biosynthesis process. The absorption and weight of the nanoparticles depended on the
reaction of the chemical with recombinant bromelain. 3D plots showed that the optimal condition
for high responses mostly depends on temperature and time.

Matched MeSH terms: Chlorides
Fulltext Antioxidant analysis of different parts of Carica papaya

Maisarah, A.M., Nurul Amira, B., Asmah, R., Fauziah, O.

International Food Research Journal, 2013;20(3):1043-1048.
MyJurnal

This study was conducted to compare the total antioxidant activity (TAA), total phenolic content (TPC) and total flavonoid content (TFC) from the different parts of papaya tree including their ripe and unripe fruit, seeds and the young leaves. Two methods namely DPPH radical scavenging activity and ß-carotene bleaching assay were used to determine the TAA, whereas TPC was determined by Folin-Ciocalteu’s method while TFC by aluminium trichloride (AlCl3). For these purposes, methanolic extracts (80%) were prepared. The results showed that the highest antioxidant activity through ß-carotene bleaching assay was observed in unripe fruit (90.67 ± 0.29%) followed by young leave, ripe fruit and the seed. In other hand, young leaves exhibited a significant higher scavenging effect compared to others and the dose required in reducing the absorbance of DPPH control solution by 50% (EC50) was calculated at 1.0 ± 0.08mg/ml. The EC50 values were 4.3 ± 0.01mg/ml, 6.5 ± 0.01mg/ml and 7.8 ± 0.06mg/ml for unripe fruit, ripe fruit and seeds respectively. Interestingly, both TPC and TFC also showed that young leaves had the highest antioxidant content (424.89 ± 0.22mg GAE/ 100 g dry weight and 333.14 ± 1.03mg rutin equivalent/ 100 g dry weight, respectively). Statistically, Pearson correlation showed there were positive correlations between TPC and TFC with antioxidant activity assayed by DPPH radical scavenging assay (r=0.846 and r=0.873, respectively). However there was no correlation between TPC and TFC with ß-carotene bleaching activity. In brief, taken into account all the parameters measured, antioxidants were highly remarkable in the sequence of young leaves > unripe fruit > ripe fruit > seed. Nevertheless, further investigation for isolation and identification of the phytoconstituents responsible for antioxidant activity is desirable.

Matched MeSH terms: Chlorides
Fulltext Comparison of antioxidant properties of pomelo [Citrus Grandis (L) Osbeck] varieties

Toh, J.J., Khoo, H.E., Azrina, A.

International Food Research Journal, 2013;20(4):1661-1668.
MyJurnal

This study aimed to compare the antioxidant content and antioxidant capacity of pulp and peel of two varieties of pomelo fruit (Tambun White and Tambun Pink). Antioxidants including total phenolic content, total flavonoid content and ascorbic acid content were determined using Folin-Ciocalteu reagent assay, aluminium chloride colorimetric assay and AOAC method, respectively. Antioxidant capacity of pomelo pulp and peel was measured using ferric reducing antioxidant potential and trolox equivalent antioxidant capacity assays. The peels of both pomelo fruits had higher antioxidant content and capacity than their pulps. Moreover, the white variety of pomelo had higher antioxidant content and capacity compared to the pink counterpart. Trolox equivalent antioxidant capacity of the samples was positively high correlated with total phenolic content (r = 0.978) and total flavonoid content (r = 0.959), except for ascorbic acid. Therefore, pomelo peel from white variety possessed higher antioxidant properties and it is potentially rich sources of natural antioxidants.

Matched MeSH terms: Chlorides
Fulltext X-ray diffraction study of clay from north-west Peninsular Malaysia

Ahmad Saat, Zaini Hamzah

Journal of Nuclear and Related Technologies, 2008;2008(1):1-9.
MyJurnal

Clay has been regarded as very important natural industrial materials. All these industries exploit the properties that clay can be molded into any shape and fired to dry without losing its form. A study was carried out on clay samples from eight sites in the north-eastern part of Peninsular Malaysia. The study was accomplished by using X-ray diffraction (XRD) technique. The x-ray diffraction spectra obtained enable the determination of the lattice spacing associated with the types of clay and nonclay minerals present in the samples. Results of the study shows that the major components of clay minerals present in all samples studied are kaolinite and illite. The presence of kaolinite is confirmed by firing test in which the kaolinite diffraction peaks disappeared upon heating the samples at 600 o C. The presence of non-clay minerals such as quartz, mica, feldspar and chlorite are also observed.

Matched MeSH terms: Chlorides
Fulltext The Role of Zinc Chloride in Enhancing Mechanical, Thermal and Electrical Performance of Ethylene Vinyl Acetate/Carbonized Wood Fiber Conductive Composite

Mohd Pisal MH, Osman AF, Jin TS, Rahman RA, Alrashdi AA, Masa A

Polymers (Basel), 2021 Feb 17;13(4).
PMID: 33671304 DOI: 10.3390/polym13040600

Carbonized natural filler can offer the production of low cost composites with an eco-friendliness value. The evolving field of electronics encourages the exploration of more functions and potential for carbonized natural filler, such as by modifying its surface chemistry. In this work, we have performed surface modification on carbonized wood fiber (CWF) prior to it being used as filler in the ethylene vinyl acetate (EVA) composite system. Zinc chloride (ZnCl2) with various contents (2 to 8 wt%) was used to surface modify the CWF and the effects of ZnCl2 composition on the surface morphology and chemistry of the CWF filler were investigated. Furthermore, the absorptive, mechanical, thermal, and electrical properties of the EVA composites containing CWF-ZnCl2 were also analyzed. SEM images indicated changes in the morphology of the CWF while FTIR analysis proved the presence of ZnCl2 functional groups in the CWF. EVA composites incorporating the CWF-ZnCl2 showed superior mechanical, thermal and electrical properties compared to the ones containing the CWF. The optimum content of ZnCl2 was found to be 6 wt%. Surface modification raised the electrical conductivity of the EVA/CWF composite through the development of conductive deposits in the porous structure of the CWF as a channel for ionic and electronic transfer between the CWF and EVA matrix.

Matched MeSH terms: Chlorides
Synthesis of some N-sulfonated derivatives of 1-[(E)-3-phenyl-2-propenyl]piperazine as suitable antibacterial agents

Abbasi MA, Ijaz M, Aziz-Ur-Rehman -, Siddiqui SZ, Ali Shah SA, Shahid M, et al.

Pak J Pharm Sci, 2020 Jul;33(4):1609-1616.
PMID: 33583794

In the planned research work, the nucleophilic substitution reaction of 1-[(E)-3-phenyl-2-propenyl]piperazine (1) was carried out with different sulfonyl chlorides (2a-g) at pH 9-10 to synthesize its different N-sulfonated derivatives (3a-g). The structures of the synthesized compounds were characterized by their proton-nuclear magnetic resonance (1H-NMR), carbon-nuclear magnetic resonance (13C-NMR) and Infra Red (IR) spectral data, along with CHN analysis. The inhibition potential of the synthesized molecules was ascertained against two bacterial pathogenic strains i.e. Bacillus subtilis and Escherichia coli. It was inferred from the results that some of the compounds were very suitable inhibitors of these bacterial strains. Moreover, their cytotoxicity was also profiled and it was outcome that most of these molecules possessed moderate cytotoxicity.

Matched MeSH terms: Chlorides
Formation of high-density crystalline-shape gold nanoparticles on indium tin oxide surfaces: effects of alcohothermal seeding

Umar AA, Salleh MM, Majlis BY, Oyama M

J Nanosci Nanotechnol, 2011 Jun;11(6):4974-80.
PMID: 21770130

We found that the gold nanoparticles with high-density and crystalline-shape, such as nanocubes, nanobricks, pentahedral nanorods, etc., can be realized on the surface by using a seed-mediated growth method with a unique seeding process, namely alcohothermal. By using a conventional growth solution that contains HAuCl4, cetyltrimethylammonium bromide, NaOH and ascorbic acid, gold nanoparticles with crystalline-morphology (gold nanocrystals) of yield up to ca. 95%, can be prepared. An alcohothermal seeding was carried out by a thermal reduction of gold ions from an alcoholic solution of gold salt on the surface through an annealing process at a moderate temperature, namely 250 degrees C. It is believed that the unique initial characteristic (presumably the structures) of the gold nanoseeds particles as the result of peculiar nanoseeds formation process, prepared using this approach, instead of a simple thermal restructuring of the as prepared nanoseeds as confirmed by the results of annealing treatment on the nanoseed prepared using the normal and in-situ reduction seeding, was as the driving factor for the projected growth of crystalline-shape gold nanoparticles on the surface. The crystalline-shape gold nanoparticles modified-surface should find a potential application in catalysis, sensors and SERS.

Matched MeSH terms: Chlorides
Enhanced adsorption selectivity of Au(III) over Cu(II) from acidic chloride solutions by chitosan/palm kernel fatty acid distillate/magnetite nanocomposites

Chang SH, Jampang AOA

Int J Biol Macromol, 2023 Dec 01;252:126491.
PMID: 37625756 DOI: 10.1016/j.ijbiomac.2023.126491

This work aimed to develop a modified chitosan adsorbent with enhanced adsorption selectivity for Au(III) over Cu(II) from acidic chloride solutions using low-cost and green raw materials. Various adsorbents, i.e., chitosan powder, chitosan microbeads, chitosan/palm kernel fatty acid distillate (PKFAD) microcomposites, magnetite nanoparticles, and chitosan/PKFAD/magnetite nanocomposites (CPMNs), were first evaluated for their ability to adsorb Au(III) and Cu(II) from single- and binary-metal solutions across different pH levels, followed by parametric analysis of Au(III) and Cu(II) adsorption from binary- and multi-metal solutions onto CPMNs, Au(III) desorption from Au(III)-loaded CPMNs, and reusability of CPMNs. Finally, Au(III)-loaded CPMNs were characterized with SEM-EDX, XRD, FTIR, and XPS to confirm the proposed adsorption mechanisms. Among all the adsorbents studied, CPMNs exhibited outstanding performance in adsorbing Au(III) from an equimolar binary Au(III)-Cu(II) solution, achieving the highest equilibrium adsorption capacity of 0.479 mmol/g (94.4 mg/g) without reaching saturation. Under optimal adsorption conditions of pH 3, 1 g/L CPMN dosage, and 90 min contact time, CPMNs adsorbed 96 % of Au(III) with a selectivity over Cu(II) exceeding 99 %. CPMNs demonstrated excellent reusability, maintaining over 80 % adsorption and desorption efficiencies for 5 cycles. The proposed adsorption mechanisms of CPMNs for Au(III) encompass electrostatic attraction, hydrogen bonding, solvation, and reduction.

Matched MeSH terms: Chlorides
Fulltext Impaired neuronal KCC2 function by biallelic SLC12A5 mutations in migrating focal seizures and severe developmental delay

Saitsu H, Watanabe M, Akita T, Ohba C, Sugai K, Ong WP, et al.

Sci Rep, 2016 07 20;6:30072.
PMID: 27436767 DOI: 10.1038/srep30072

Epilepsy of infancy with migrating focal seizures (EIMFS) is one of the early-onset epileptic syndromes characterized by migrating polymorphous focal seizures. Whole exome sequencing (WES) in ten sporadic and one familial case of EIMFS revealed compound heterozygous SLC12A5 (encoding the neuronal K(+)-Cl(-) co-transporter KCC2) mutations in two families: c.279 + 1G > C causing skipping of exon 3 in the transcript (p.E50_Q93del) and c.572 C >T (p.A191V) in individuals 1 and 2, and c.967T > C (p.S323P) and c.1243 A > G (p.M415V) in individual 3. Another patient (individual 4) with migrating multifocal seizures and compound heterozygous mutations [c.953G > C (p.W318S) and c.2242_2244del (p.S748del)] was identified by searching WES data from 526 patients and SLC12A5-targeted resequencing data from 141 patients with infantile epilepsy. Gramicidin-perforated patch-clamp analysis demonstrated strongly suppressed Cl(-) extrusion function of E50_Q93del and M415V mutants, with mildly impaired function of A191V and S323P mutants. Cell surface expression levels of these KCC2 mutants were similar to wildtype KCC2. Heterologous expression of two KCC2 mutants, mimicking the patient status, produced a significantly greater intracellular Cl(-) level than with wildtype KCC2, but less than without KCC2. These data clearly demonstrated that partially disrupted neuronal Cl(-) extrusion, mediated by two types of differentially impaired KCC2 mutant in an individual, causes EIMFS.

Matched MeSH terms: Chlorides/metabolism
Fulltext A randomized cross-over study comparing the performance of HD integra™ central concentrate system versus pre-produced concentrate in hemodialysis

Fauziah K, Go KW, Ghazali A, Zaki M, Lim TO

BMC Nephrol, 2017 Apr 03;18(1):123.
PMID: 28372556 DOI: 10.1186/s12882-017-0537-2

BACKGROUND: Pre-produced bicarbonate concentrates (PPC) are still widely used in developing countries despite its cost and risk but Central Concentrate System (CCS) is lacking in data to support its wider adoption.
METHODS: We conducted an 8-week randomized crossover study on 16 Hemodialysis machines to compare CCS versus PPC. Performance is assessed by solute concentrations while safety is assessed by microbial count, endotoxin level and adverse event reporting.
RESULTS: Microbial counts and endotoxin levels were monitored on 48 occasions during the 8-week study for the CCS arm of the study. The levels were all below the action limit during the study. No patient reported any adverse events. Dialysate Sodium, Chloride and Bicarbonate concentrations were measured on a total of 128 occasions for each arm of the study. The relative deviations of Sodium, Chloride and Bicarbonate concentration were within ±5% of their nominal values for both. The 95% Confidence Intervals for the ratio of the mean solute concentrations on the CCS to PPC lie within the tolerance limit of ±5%.
CONCLUSION: Modern CCS is bacteriologically safe and its performance statistically equivalent to PPC.

Matched MeSH terms: Chlorides/analysis
Influence of alkaline hydrogen peroxide pre-hydrolysis on the isolation of microcrystalline cellulose from oil palm fronds

Owolabi AF, Haafiz MK, Hossain MS, Hussin MH, Fazita MR

Int J Biol Macromol, 2017 Feb;95:1228-1234.
PMID: 27836655 DOI: 10.1016/j.ijbiomac.2016.11.016

In the present study, microcrystalline cellulose (MCC) was isolated from oil palm fronds (OPF) using chemo-mechanical process. Wherein, alkaline hydrogen peroxide (AHP) was utilized to extract OPF fibre at different AHP concentrations. The OPF pulp fibre was then bleached with acidified sodium chlorite solution followed by the acid hydrolysis using hydrochloric acid. Several analytical methods were conducted to determine the influence of AHP concentration on thermal properties, morphological properties, microscopic and crystalline behaviour of isolated MCC. Results showed that the MCC extracted from OPF fibres had fibre diameters of 7.55-9.11nm. X-ray diffraction (XRD) analyses revealed that the obtained microcrystalline fibre had both celluloses I and cellulose II polymorphs structure, depending on the AHP concentrations. The Fourier transmission infrared (FTIR) analyses showed that the AHP pre-hydrolysis was successfully removed hemicelluloses and lignin from the OPF fibre. The crystallinity of the MCC was increased with the AHP concentrations. The degradation temperature of MCC was about 300°C. The finding of the present study showed that pre-treatment process potentially influenced the quality of the isolation of MCC from oil palm fronds.

Matched MeSH terms: Chlorides/chemistry
Testosterone decreases fluid and chloride secretions in the uterus of adult female rats via down-regulating cystic fibrosis transmembrane regulator (CFTR) expression and functional activity

Mohd Mokhtar H, Giribabu N, Kassim N, Muniandy S, Salleh N

J Steroid Biochem Mol Biol, 2014 Oct;144 Pt B:361-72.
PMID: 25125390 DOI: 10.1016/j.jsbmb.2014.08.007

Estrogen is known to stimulate uterine fluid and Cl(-) secretion via CFTR. This study investigated testosterone effect on these changes in a rat model.

Matched MeSH terms: Chlorides/metabolism*
Micropropagation of Elaeis guineensis Jacq. 'Dura': Comparison of three basal media for efficient regeneration

Muniran F, Bhore SJ, Shah FH

Indian J Exp Biol, 2008 Jan;46(1):79-82.
PMID: 18697576

Three basal plant tissue culture media, namely, N6, MS, and modified Y3, were compared to optimize micropropagation protocol for E. guineensis. Full strength media were used separately to regenerate plantlets directly using immature zygotic embryos (IZEs), and through somatic embryogenesis of calli obtained from IZEs. The plantlets regenerated by direct regeneration on three media were examined for shoot length and rooting percentage. For the induction of callus, somatic embryogenesis, and rooting modified Y3 medium was the most effective. In conclusion, the results indicate that modified Y3 medium is the most suitable for direct regeneration, callus induction and somatic embryogenesis in E. guineensis.

Matched MeSH terms: Chlorides/chemistry
Application of response surface methodology (RSM) to optimize coagulation-flocculation treatment of leachate using poly-aluminum chloride (PAC) and alum

Ghafari S, Aziz HA, Isa MH, Zinatizadeh AA

J Hazard Mater, 2009 Apr 30;163(2-3):650-6.
PMID: 18771848 DOI: 10.1016/j.jhazmat.2008.07.090

Coagulation-flocculation is a relatively simple physical-chemical technique in treatment of old and stabilized leachate which has been practiced using a variety of conventional coagulants. Polymeric forms of metal coagulants which are increasingly applied in water treatment are not well documented in leachate treatment. In this research, capability of poly-aluminum chloride (PAC) in the treatment of stabilized leachate from Pulau Burung Landfill Site (PBLS), Penang, Malaysia was studied. The removal efficiencies for chemical oxygen demand (COD), turbidity, color and total suspended solid (TSS) obtained using PAC were compared with those obtained using alum as a conventional coagulant. Central composite design (CCD) and response surface method (RSM) were applied to optimize the operating variables viz. coagulant dosage and pH. Quadratic models developed for the four responses (COD, turbidity, color and TSS) studied indicated the optimum conditions to be PAC dosage of 2g/L at pH 7.5 and alum dosage of 9.5 g/L at pH 7. The experimental data and model predictions agreed well. COD, turbidity, color and TSS removal efficiencies of 43.1, 94.0, 90.7, and 92.2% for PAC, and 62.8, 88.4, 86.4, and 90.1% for alum were demonstrated.

Matched MeSH terms: Chlorides*
Fulltext Thermodynamic study of the complexation of p-isopropylcalix[6]arene with Cs+ cation in dimethylsulfoxide-acetonitrile binary media

Ahmadzadeh S, Kassim A, Rezayi M, Rounaghi GH

Molecules, 2011 Sep 22;16(9):8130-42.
PMID: 21941227 DOI: 10.3390/molecules16098130

The complexation reactions between the macrocyclic ionophore, p-isopropylcalix[6]arene and Cs+ cation were studied in dimethylsulfoxide-acetonitrile (DMSO-AN) binary non-aqueous solvents at different temperatures using a conductometry method. The conductance data show that the stoichiometry of the (p-isopropylcalix[6]-arene·Cs)+ complex in all binary mixed solvents is 1:1. The stability of the complexes is affected by the composition of the binary solvent media and a non-linear behavior was observed for changes of log K(f) of the complex versus the composition of the binary mixed solvents. The thermodynamic parameters (DH°(c) and DS°(c)) for formation of (p-isopropyl-calix[6]arene·Cs)+ complex were obtained from temperature dependence of the stability constant and the obtained results show that the (p-isopropylcalix[6]arene·Cs)+ complex is enthalpy destabilized, but entropy stabilized, and the values of the mentioned parameters are affected strongly by the nature and composition of the binary mixed solvents.

Matched MeSH terms: Chlorides/chemistry*
Sequential flow injection determination of chlorine species using a triiodide-selective electrode detector

Saad B, Wai WT, Ali AS, Saleh MI

Anal Sci, 2006 Jan;22(1):45-50.
PMID: 16429771

A flow injection analysis (FIA) method for the determination of four residual chlorine species, namely combined available chlorine (CAC), free available chlorine (FAC), total available chlorine (TAC) and chlorite (ClO2-) was developed using a flow-through triiodide-selective electrode as a detector. An important strategy of speciation studies utilized the kinetic discrimination of reactions between the CAC and FAC with Fe2+, which was applied to the speciation of FAC, CAC and TAC. The speciation of available chlorine species and chlorite (an oxychlorine species) was achieved by using the same set-up, but using flow streams of different pH. The effects of the pH of the carrier stream, the flow rate and the sample volume were studied. The method exhibited linearity from 2.8 x 10(-6) to 2.8 x 10(-4) M active chlorine (expressed as OCl-) with a detection limit of 1.4 x 10(-6) M. The selectivity of the method was studied by examining the minimum pH for the oxidation of iodide by other oxidants, and also by assessing the potentiometric selectivity coefficients. The proposed method was successfully applied to the determination of chlorine species in tap water, and disinfecting formulations where good agreement occurred between the proposed and standard methods were found.

Matched MeSH terms: Chlorides/analysis*

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