Syed Sakhawat Shah

• PhD
• Ex-Vice Chancellor at Hazara University

This study introduces the environmentally friendly synthesis of Ag2O, TiO2, and Ni-doped SnO2 nanoparticles (NPs) and their application in detecting and removing bromothymol blue (BTB) dye from wastewater. The unique electronic properties and quantum size effects of NPs allow them to surpass conventional materials. Characterization of the synthesiz...

Herein, we report the synthesis, characterization, and application of TiO2/ZnO and La-doped ZnO nanocomposites for the detection and degradation studies of Malachite Green (MG). TiO2/ZnO and La-doped ZnO nanocomposites were synthesized by reflux and hydrothermal methods, respectively, and characterized by UV–visible spectroscopy, X-ray diffraction,...

The pre-modification of surfactant counterions using transition metal salts provides a means to activate the interface using corresponding properties of metal ions. In this work, a cationic surfactant cetyltrimethylammonium bromide (CTAB) was modified by pre-mixing metal chlorides (FeCl3, CuCl2 and ZnCl2) and CTAB in 1:1 molar ratio using methanol...

Interactions between dyes and surfactants is a well-established research area. It is important to interpret the missing links related to the differences between the relatively newer surfactant entrants with respect to their modified counterions and their conventional counterparts. In this research, we explored and compared the interactions of a com...

The optical properties of amphiphilic hemicyanine dyes with variable hydrophobicity, confined within anionic micelles of sodium dodecylbenzenesulfonate (NaDDBS) have been studied by UV–visible absorption spectroscopy. The confinement constant, Kconf has been determined for each entrapped dye. The ion-pair formation between dye and surfactant causes...

A cost-effective, one-pot synthesis approach is reported to fabricate Rhodamine 6G (R6G) silica hybrid xerogels. Polyvinyl alcohol (PVA) is used as a non-ionic surfactant to homogeneously trap the dye in silica matrix. Presence of R6G in silica matrix is confirmed through Fourier Transform Infrared (FTIR) spectroscopy and Thermo Gravimetric Analysi...

A controlled sol-gel synthesis incorporated with electrospinning is employed to produce polyacrylonitrile-silica (PAN-silica) fibers. Hybrid fibers are obtained with varying amounts of silica precursor (TEOS in DMF catalyzed by HCl) and PAN. Solution viscosity, conductivity and surface tension are found to relate strongly to the electrospinnability...

Poly(vinyl alcohol) (PVA)-silica hybrids with exceptionally reduced solubility in water were synthesized. The hybrid xerogels were fabricated through sol-gel processing of a mixture of PVA and the acid-catalyzed silica precursor tetraethoxysilane. The effects of varying ratios of PVA and silica precursor on the surface structure, thermal properties...

To model the binding to biomembranes, the interactions of potent N-m-tolylbenzamide (NTB) with a cationic surfactant, cetyltrimethylammonium bromide (CTAB) and an anionic surfactant, sodium dodecyl sulfate (SDS), have been investigated. The study was carried out by quantifying the absorption and fluorescence emission spectra of NTB as a function of...

The solubilization of four chalcones, between aqueous and micellar phases of ionic surfactants (SDS and CTAB), was investigated by conductivity and cyclic voltammetry (CV) techniques. From conductivity data, a decrease in the critical micellar concentration (CMC) of the surfactants, in presence of the chalcones was ascribed to the decreased charge...

Effect of Sodium Dodecyl Sulphate (SDS) on sample transport efficiency, nebulisation and overall contribution in analysis using Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES) for different analytes has been studied. The objective of this study was to investigate the effect of surfactant on the quality of aerosols results in enhan...

Preparation of colloidal silver nanoparticles has been carried out by salt reduction method and confirmed by the appearance of plasmon band in the visible region. The prepared nanoparticles were subjected to acidic and basic environments. The plasmon band was studied as a function of time under the described conditions and hence used as a stability...

A laboratory simulation study was carried out to check the possibility of alkaline in-situ leaching of uranium from an arkosic type of sandstone recovered from a specific location at a depth of 300-500 m. The ore body was overlaying impervious clay shale below the water table. Different CO 3-2 containing soluble salts were tested as complexing agen...

A series of silica xerogels was synthesized by using TEOS as the silica precursor and a non ionic surfactant Triton X100 (TX 100) and a cationic surfactant Hexadecyltrimethylammonium Bromide (CTAB) as templates. The xerogels were synthesized through 2-way catalysis using ultrasonic radiations for homogeneous mixing of the precursors and template. T...

Short chain phenylalkanoic acids have been investigated by UV spectroscopy to ascertain their solubilization into cationic surfactant, cetyltrimethylammonium bromide (CTAB), and anionic surfactant, sodium dodecyl sulfate (SDS). The increasing surfactant concentrations caused bathochromic shift in the spectra of additive acids. CTAB exhibited greate...

We report on the synthesis of poly(vinyl alcohol) (PVA)-silica hybrid nanofibers via sol-gel electrospinning. Silica is synthesized through acid catalysis of a silica precursor (tetraethyl orthosilicate (TEOS) in ethanol-water), and fibers are obtained by electrospinning a mixture of the silica precursor solution and aqueous PVA. A systematic inves...

The role of chemistry in attaining sustainable development is not usually considered in a positive way. Generally chemistry, chemists and chemicals are taken as causes of the problem. The green chemistry revolution is providing quite a number of challenges to those who practise chemistry in industry, education and research. Other than these challen...

The solubilization and interactions of phenylalkanoic acids induced by the cationic surfactant, cetyltrimethylammonium bromide (CTAB) and the anionic surfactant sodium dodecyl sulfate (SDS) was investigated spectropho-tometrically at 25.0 °C. The UV spectra of the additives (acids) were measured with and without surfactant above and below the criti...

Preparation of colloidal silver nanoparticles has been carried out by salt reduction method and confirmed by the appearance of plasmon band in the visible region. The prepared nanoparticles were subjected to acidic and basic environments. The plasmon band was studied as a function of time under the described conditions and hence used as a stability...

PVA/silica hybrid xerogels were synthesized by sonohydrolysis of a mixture of 2-way catalyzed TEOS and water solution of PVA. PVA was successfully removed from the xerogels through calcination and its removal was confirmed through TGA analysis of the calcined gel. Microstructure of the gels was studied through SEM, XRD and FTIR. Nitrogen sorption s...

Conductometric behaviour of 1-alkanols (C5-C10) in organised solutions of sodium dodecylbenzenesulfonate (SDBS) is investigated. Interaction of each alkanol with anionic surfactant is reflected in terms of association constants, Kc. It is observed that self-assembly of SDBS is induced by the alkanol addition. The depression in critical micelle conc...

H2O2 was used as oxidizing agent of the insoluble tetravalent uranium into the soluble hexavalent state along with NH 4HCO3 as complexing agent in tap water solvent. The study was conducted to look at the possibility of commercial scale insitu leaching of uranium from an underground arkosic sandstone ore deposit. It was found that the peroxide was...

A viable cost-effective approach employing mixtures of non-ionic surfactants Triton X-114/Triton X-100 (TX-114/TX-100), and subsequent cloud point extraction (CPE), has been utilized to concentrate and recycle inorganic nanoparticles (NPs) in aqueous media. Gold Au- and palladium Pd-NPs have been pre-synthesized in aqueous phases and stabilized by...

Heavy metals (Pb2+, Co2+, Ni2+, Cu2+, Zn2+) were removed from aqueous solution by ultrafiltration enhanced by chelation with sericin, a naturally occurring biopolymer. Sericin is a polypeptide comprising of many amino groups with lone pairs of electrons which can be donated to d-electron deficient metal ions via chelation. As such, the small metal...

A microemulsion-based drug delivery system has been designed for Diclofenac Sodium (DS) comprising Span 60, 1-Propanol, Water, and Lemon Oil. The microemulsion system has been characterized by a pseudo-ternary phase diagram using the water titration method. The properties and structure of this system have been studied by the use of refractive index...

Water-in-oil microemulsions (w/o μEs) stabilized by the cationic surfactant cetyltrimethylammonium chloride (CTACl) have been used as reaction media to generate Au nanoparticles (Au-NPs). In addition the pure μEs have been used as media to disperse Au and Pd-NPs, which have been pre-synthesised in aqueous phases and stabilized by sodium 2-mercaptoe...

Micellar enhanced ultrafiltration technique was employed to remove the methylene blue from the aqueous solution. Sodium dodecyl sulfate and regenerated cellulose membrane was used to retain dye from the aqueous stream in stirred ultrafiltration cell. Rejection percentage increases from 75% to 99% with increase in surfactant concentration. Permeate...

The partitioning behaviour of four newly synthesized chalcones between aqueous and micellar phases of ionic surfactants (SDS and CTAB) was investigated using UV/Visible spectroscopy. The simple absorption spectra were recorded to study the interaction between these drugs and surfactants (in the concentration range below CMC to above CMC). The absor...

In the present study synthesis of nano hydroxyapatite; HA, Ca10(PO4)6(OH)2 using different surfactants as templates are exploited. Three surfactants such as Cetyl Trimethyl Ammonium Bromide; CTAB (cationic), Sodium Dodecyl Sulphate; SDS (anionic) and Polyoxyethylene sorbitane monolaurate; Tween 20 (nonionic) surfactants have been used as nano react...

Flavonoids are well known scavengers of activated free oxygen species. Hence they are capable of repairing oxidative damages to biological systems. The role of surfactant micelles in the radical scavenging ability or antioxidant potential of flavonoids is reviewed. It is apparent from the studies undertaken recently that micelles could significantl...

Micelle–water partition coefficient (Kx) of naphtholazobenzimidazole dye (NAB) in aqueous solutions of cetyltrimethylammonium bromide (CTAB) and sodium dodecyl sulphate (SDS) has been determined spectrophotometerically. Changes in absorption patterns of dye caused by surfactants and solvents were quantified in terms of dye–surfactant ratio (nD/nS)...

An approach is demonstrated toward the synthesis of four novel cyclohexenone derivatives (CDs) via a convenient route of Michael addition of ethyl acetoacetate. The molecular structures of CDs were confirmed by means of FT-IR, (1)H NMR, EIMS, UV and also by X-ray single crystal structure analysis. CDs are strongly fluorescent compounds and their fl...

Ultraviolet (UV)-visible behavior of 3,4-dihydroxy-9,10-dioxo-2-anthracenesulfonic acid sodium salt (ARS) has been studied at pH 4.0, aqueous medium, and at pH 10.0. The effects of cetyl trimethylammoniumbromide (CTAB) on the UV-visible spectra of ARS have been evaluated qualitatively as well as quantitatively in the different concentration regions...

The anthraquinoid dye, Alizarin Red S, forms an anionic moiety in aqueous solution. The complex formation of this dye was studied with the cationic surfactant, cetyltrimethylammonium bromide, in an aqueous environment at low surfactant concentrations. The complex was studied with the help of ultraviolet-visible spectroscopy. A method of continuous...

The aggregation induced by Alizarin Yellow R (AYR) in the cationic surfactant, cetyltrimethylammonium bromide (CTAB), was investigated by measuring their UV–visible absorption spectra. Conductance measurements as a function of surfactant concentration below and above the critical micelle concentration (CMC) were studied. CTAB aggregation takes plac...

Formulation of a new oil-in-water (o/w) microemulsion composed of castor oil/Tween 80/ethanol/phosphate buffer for enhancing the loading capacity of an anti-inflammatory drug piroxicam has been accomplished. The pseudo-ternary phase diagram has been delineated at constant surfactant/cosurfactant ratio (1:2). The internal structure of so created fou...

Ultraviolet (UV) and Fourier transformed infrared (FTIR) spectra of ciprofloxacin hydrochloride (Cpf) were studied under different pH conditions. The effect of aqueous, strong acidic, (pH 0.5-1.0) and a basic (pH 9.2) conditions on spectral behavior of Cpf was investigated in aqueous as well as in micellar environment of sodium dodecyl sulfate (SDS...

Ciprofloxacin hydrochloride (Cpf) has been studied in aqueous for its fluorescence behavior. Hence forth, its interaction is checked with sodium dodecyl sulfate (SDS), an anionic surfactant using steady state fluorescence spectroscopy. Binding was shown by Cpf and SDS in the premicellar region of SDS. The drug becomes free from the SDS monomers in...

Electrical Conductivities were measured to calculate critical aggregation concentration (cac) of dexamethasone sodium phosphate (DSP) at various temperature from 298-313K with an increment of 5 K and in this way its thermodynamic parameters like Gibbs energy of aggregation (Delta G degrees(agg)), enthalpy of aggregation (Delta H degrees(agg)) and e...

Sorption capacities for cadmium, Cd(II) on indigenously prepared, steam activated, untreated, surfactant-modified carbon powder, from husk and pods of Moringa oleifera were investigated. The optimized conditions for all the experimental runs were pH 8.0 ± 0.2, temperature 30 ± 0.5 °C, contact time 120 min, agitation speed 160 rpm, initial metal con...

Complex formation of hemicyanine dyes within anionic surfactant sodium dodecyl sulfate is investigated using differential absorbance method. Micelle–water partition coefficients are calculated as a ratio of the mole fractions of dye in corresponding phases. The thermodynamic parameters highlight the energy efficiency of the process. Conductometric...

The interaction of hydrophobic dye pyrene with sodium dodecyl sulphate (SDS), an anionic surfactant, was studied in the process of solubilization. Difference UV-Visible spectroscopy was used to carry out the study. The partition coefficient (K(x)), and number of dye molecules incorporated per micelle (n) was calculated. High Kx value shows that pyr...

The interaction of anticancer chalcone [AMC, 1-(4'-aminophenyl)-3-(4-N,N-dimethylphenyl)-2-propen-1-one] with DNA has been explored using electrochemical, spectroscopic and viscometric techniques. A shift in peak potential and decrease in peak current were observed in cyclic voltammetry and hypochromism accompanied with bathochromic shift were noti...

In the present investigation, the cyclic load deformation behaviour of soil-fly ash layered system is studied using different intensities of failure. load (I = 25%. 50% and 75%) with varying number of cycles (N 10, 50 and 100). All attempt has been made to establish the use fly ash as a fill material for embankments ( of highways and railways and t...

Critical micelle concentration of sodium dodecyl sulfate (SDS) was determined using condunctance and fluorescence method. Effect of low concentration of pyrene was checked on the Cmc of SDS conductometrically. The Cmc was determined from the data using two different methods. ORIGIN software shown up as a much better and easier way for the theoretic...

Transport of Zr ions through tri-n-octylamine and di-cylohexylamine xylene based liquid membranes supported in polypropylene microporous films has been studied and found that HNO3 is a better acid in the feed and water and methyl-s-úccinic acid are the stripping agents which can be used to transport Zr ions. The values of flux (J) and permeability...

An indigenously prepared, steam activated and chemically modified carbon from husk and pods of Moringa oleifera (M. oleifera), an agricultural waste, was comparatively examined as an adsorbent for the removal of lead from aqueous solutions. Studies were conducted as a function of contact time, initial metal concentration, dose of adsorbent, agitati...

Diesel engines exhausting gaseous emission and particulate matter have long been regarded as one of the major air pollution sources, particularly in metropolitan areas, and have been a source of serious public concern for a long time. The emulsification method is not only motivated by cost reduction but is also one of the potentially effective tech...

Leaves, stems and fruit peelings of chickpea (Cicer arientinum L.) were successfully utilized for the accumulation of lead ions from aqueous solutions onto their surfaces. The rate and extent of accumulation were affected by pH, particle size, contact time and the initial concentration of Pb(II) ions, respectively. The sorption capacities of leaves...

The Force–Area (F–A) isotherms of Polyoxyethylene-octadecanol (PEO) monolayers at the air-water interface were recorded using Langmuir-Wilhelmy Balance. The effects of changing hydrophilicity of the spread molecules, temperature and different salts in the subphase on the PEO monolayers are determined and discussed. The changes in the water structur...

Viscosities of aqueous solutions of nitrates of Na+ K +, Mg++ Ca++ and Sr++ were determined by using a thermostated Ubbelohde flow, viscometer in the range of concentrations and temperatures from 20 to 50°C. From the experimental results; Ion-Solvent interaction terms (β-Coefficients) were calculated in the concentration range 0.1 to 4M, by using a...

The reductive electrochemistry of methyl viologen (MV2+) was surveyed in the presence of sodium dodecyle sulfate (SDS), sodium dodecyl benzene sulfonate (SDBS), Dodecyl ethyl dimethyl ammonium bromide (DEDAB) and Sorbitane monolaurate (SPAN 20) micelles, by considering the UV-visible technique. The effect of different surfactants on the reduction o...

Objective: To evaluate technetium-99m methylene diphosphonate ( 99mTc-MDP) as a noninvasive tumor-localizing agent in patients with palpable breast masses and to differentiate malignant from benign breast lesions. Design: It was an observational and experimental study. Place and Duration of Study: The study was conducted at the Institute of Radioth...

The effect of concentration on electrical conductance of SDS solution from 293.15–313.15 K above and below the CMC was studied. The micellization parameters, i.e. degrees of counterion binding (β) and aggregation numbers (n) were determined at different temperatures. The mass action model (MAM) was applied to calculate other micellization parameter...

The partition coefficient, Kc, of various aromatic acids between the bluk water and micelles of sodium dodecyl sulfate (SDS) was determined at 25°C by differential spectroscopic method. The Kc values were utilized to compute standard free energy change of solubilization, ΔGp°, and relative solubility of additive acids. The solubilization parameters...

Objective: The study aimed at observing the factors which might influence the axillary lymph node metastases. Design: The study was an observational one. Place and Duration of Study: The study was carried out at the Surgical A Unit of Khyber Teaching Hospital, Peshawar over one year Subjects and Methods: Fifty cases of carcinoma breast undergoing m...

The solubilization of trans-amphiphilic hemicyanine dyes by the micelles of an ionic surfactant was studied by differential spectroscopic method. The critical micelle concentration (CMC) of sodium dodecylbenzenesulfonate (SDBS) with and without hemicyanine dyes was determined by conductivity measurements. The partition coefficient between the bulk...

Cationic hemicyanine dyes of the 1-methyl-4-(4-(di-n-alkylamino)-styryl) pyridinium betain type (alkyl group=methyl to butyl) have been investigated by differential spectroscopy in order to ascertain their solubilization in aqueous micellar solution of sodium dodecylbenzene sulfonate (SDBS). The differential absorption spectra were recorded as a fu...

The phase diagram of the ternary surfactant system tetradecyldimethylamine oxide (TDMAO)/HCl/1-hexanol/water shows with increasing cosurfactant concentration an L(1) phase, two L(alpha) phases (a vesicle phase L(alpha1) and a stacked bilayer phase L(alphah)), and an L(3) phase, which are separated by the corresponding two-phase regions L(1)/L(alpha...

 The phase behaviour and properties of the tetradecyldimethylamine oxide/HCl/hexanol/water quaternary surfactant system have been studied by means of electric conductivity, rheology, freeze-fracture transmission electron microscopy (FF-TEM) and small-angle neutron scattering (SANS). In this system the originally zwitterionic surfactant can become i...

The electrical conductivity of sodium dodecyl sulfate (SDS) in aqueous solution was determined up to a concentration of 10 times the critical micelle concentration. The effects of solution concentration on the various interaction parameters of SDS have been studied. The mass action model was applied to micelle formation to calculate the micellizati...

The interaction of amphiphilic hemicyanine dyes i.e. (dialkylamino)stilbazolium butyl sulphonate (R = −CH3 to −C5H11) with sodium dodecyl sulphate (SDS), an anionic surfactant, in the process of solubilization was studied by absorption spectra as a function of surfactant concentrations above and below critical micelle concentration. Absorption spec...

Solubilization in terms of hydrophobic interactions of amphiphilic hemicyanine dyes by micelles of the anionic surfactant sodium dodecyl sulfate was studied. The critical micelle concentration was determined by a specific conductivity method. The water–micelle partition coefficient (Kx) of these dyes was determined using a differential absorbance t...

The critical micelle concentration (CMC) of sodium dodecyl benzene sulfonate (SDBS) in the presence of small amounts of 1-alkanols (C1-C4,C6, C8) was determined by the conductivity method at 25°C. The CMC decreases linearly with an increase in the concentration (Ca) of the added 1-alkanols, within their low concentration ranges. The limiting slopes...

Cationic hemicyanine dyes, 1-methyl-4[4-(di-n-alkylamino)styryl] pyridinium betaines containing dialkyl chains in the range C1 to C4 were synthesized and characterized. The interactions of dyes with cationic surfactant, cetyltrimethylammonium bromide (CTAB) and an anionic surfactant, sodium dodecyl sulfate (SDS) were studied by measuring their visi...

The interaction of 1-alkanols (C1-C4, C6 and C8) with cetyhrimethyl ammonium bromide (CTAB), a cationic surfactant, was studied by a conductivity method at 25.0°C. The critical micelle concentration (CMC) of CTAB decreased linearly with an increase in the concentration of added 1-alkanols within their low concentration regions. The water-micelle pa...

The hydrophobic interaction of amphiphilic hemicyanine dyes, i.e. (dimethylamino)stilbazolium butyl sulphonate (I) and (dihexylamino)stilbazolium butyl sulphonate (II) with cetyltrimethyl ammonium bromide (CTAB), a cationic surfactant and lithium dodecyl sulphate (LDS), an anionic surfactant, was studied through absorption spectra as a function of...

The solubilization of amphiphilic hemicyanine dyes by the micelles of a cationic surfactant, cetyltrimethylammonium bromide (CTAB), was studied as a function of surfactant concentration above the critical micelle concentration (CMC). The micelle-water partition coefficient, Kx, and the standard free energy of solubilization, DeltaG0, of these dyes...

The interaction of short chain alkanones and alkyl acetates (alkyl group = methyl to propyl) with the micelles of an anionic surfactant, sodium dodecyl sulfate (SDS), was studied by the conductivity method at 25.0°C. The critical micelle concentration (CMC) of SDS decreases linearly with the increase in the concentration of additives in the low con...

Surfactant salts of 3 different fatty acids (i .e., stearic, palmitic and laurlc acids) with lead and metals of group IIB were prepared, and the effect of the size of cations and the nature of anions on dehydrochlorination process involved during degradation of polyvinyl chloride, using conductivity and thermogravimetric techniques, have been studi...

The solubilization of amphiphilic hemicyanine dyes i.e., [1] (Dimethylamino) stilbazolium butyl sulfonate, [2] (Dihexylamino) stilbazolium butyl sulfonate, into micelles of an anionic surfac ant, sodium dodecyl benzene sulfonate (SDBS), was studied as a function of SDBS concentration above the critical micelle concentration. The micelle-water parti...

The solubilization of phenol and benzyl alcohol by the micelles of a cationic surfactant, cetyltrimethyl ammonium bromide (CTAB), and an anionic surfactant, lithium dodecyl sulfate (LDS), was studied as a function of surfactant concentration. The critical micelle concentrations (CMCs) of the two surfactants in the presence of small amounts of these...

Recent trends towards finer pitch devices and assembly with lead free solders have resulted in increased interest in NiPd plated component leads by the electronics industry. This paper discusses the performance of NiPd fine pitch components as determined by wettability, assembly performance and solder joint reliability. Assembly evaluations were pe...

The electrolytic conductivity of NaClO4 in N,N-dimethylformamide + water and tetrahydrofuran + water has been measured at 298.15 K. The limiting molar conductivity, LAMBDA0, and association constant, K(A), were derived from concentration-conductivity data with the Fuoss (1978-80) equation. The results are compared with literature values.

The electrical conductivities for dilute solutions of salicylic acid in binary mixtures of N,N-dimethylformamide, acetone, tetrahydrofuran, methanol, ethanol, and 1-propanol with water have been measured at 298.15 K. The data were analyzed with the Lee-Wheaton conductance equation for the derivation of thermodynamic dissociation constants and limit...

The dissociation constants and limiting molar conductances of benzoic and 2-, 3-, and 4-nitrobenzoic acids have been determined in binary mixtures of water with acetone and tetrahydrofuran at 25-degrees-C, respectively. The experimental data were analyzed by means of the Lee and Wheaton equation. The results are compared with those available in lit...

The molar conductances of dilute solutions of benzoic and 2-, 3-, and 4-nitrobenzoic acids in binary mixtures of ethanol and 1-propanol with water have been measured at 25C. The data were fitted to the Lee- Wheaton conductance equation for the derivation of thermodynamic dissociation constants and limiting molar conductances. The results were compa...

Thesis (doctoral)--Philipps-Universität Marburg/Lahn, 1977.