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The emergence of multidrug-resistant bacteria as a global health threat has necessitated the exploration of alternative treatments to combat bacterial infections. Among these, photocatalytic nanomaterials such as quantum dots (QDs) have shown great promise and type-I QDs have been investigated thus far. In this study, we introduce type-II InP/ZnO core/shell QDs that are ligand-exchanged with a short-chain inorganic sulfide ion (S2−) for antibacterial activity. Interestingly, InP/ZnO QDs simultaneously generate reactive oxygen species (ROS) including hydroxyl (•OH) and superoxide (O2•−) radicals, while only O2•− radicals can be released by the type-I sulfide-capped InP/ZnS QDs. The optimized nanostructure achieved effective inhibition of Pseudomonas aeruginosa and Escherichia coli bacteria growth to the level of 99.99% and 70.31% under low-intensity green light illumination of 5 mW.cm−2. Our findings highlight the importance of type-II QDs as a new avenue for developing effective antibacterial agents against drug-resistant pathogens., European Union (EU); Horizon 2020; Research and Innovation Programme; Marie SKŁODOWSKA-CURIE; STIMULUS

Penelitian tentang sintesis dan karakterisasi bioplastik dari pati ubi Nagara dengan penambahan kaolin telah dilakukan. Sintesis bioplastik dilakukan dengan metode melt intercalation dengan variasi jumlah kaolin 0-30% (b/b). Tujuan dari penelitian ini adalah untuk mengetahui pengaruh penambahan kaolin terhadap karakteristik bioplastik serta untuk mendapatkan jumlah kaolin optimum dalam pembuatan bioplastik. Bioplastik yang dihasilkan dianalisis kadar air, ketebalan, laju transmisi uap air, ketahanan air, kelarutan, biodegradasi, analisis gugus fungsional menggunakan FTIR, kuat tarik dan elongasinya. Berdasarkan hasil penelitian yang diperoleh, penambahan kaolin mempengaruhi semua karakteristik bioplastik yang dihasilkan. Nilai kuat tarik bioplastik yang dihasilkan meningkat dengan bertambahnya kaolin yang ditambahkan. Konsentrasi kaolin optimum dalam pembuatan bioplastik adalah pada penambahan 30% (b/b) kaolin dengan nilai kuat tarik sebesar 2,194 N/mm2.

The choice of suitable aluminum alloys for a particular application involves tensile strength, density, softness, formability, operability, welding ability, corrosion resistance, etc. Aluminum alloys are widely used in aircraft because of the high strength to weight ratio. The anodizing process of AA has been applied industrially to improve corrosion resistance. In this research, various factors such as (concentration of the electrolyte, temperature, and voltage) affect thickness and hardness during anodizing of AA6066 in sulphuric acid. Process factors have been modified using the Taguchi method through the Design of Experiments (DOE). The Taguchi method includes an orthogonal array of factors, a Signal-to-Noise ratio (S/N), Analysis of Variance (ANOVA), which were used to determine the optimum condition levels for aluminum alloy 6066 anodizing, and to analyze the effect of these conditions on thickness and hardness. It was found that the most effective factor on thickness and micro-hardness is the concentration of the electrolyte. Optimization test was carried out by Taguchi optimization test and the optimal conditions were determined. Finally, the anodizing was carried out on aluminum sample under the optimal conditions then scanned by SEM. The thickness and micro hardness obtained at the optimal conditions were 25μm, and 640Hv, respectively.

Ketene, a versatile reagent in production of fine and specialty chemicals, is produced from acetic acid. We investigate the synthesis of ketene from acetic acid over the (3,0;1,1) surface of Cu2O(1 0 0) through analysis of the adsorption and desorption characteristics of formic and acetic acids. The results allow us to establish a reaction mechanism for ketene formation. Observations from x-ray photoelectron spectroscopy (XPS), scanning tunneling microscopy, and temperature programmed desorption (TPD), supported by a comparison with formic acid results, suggest that acetic acid reacts with Cu2O through deprotonation to form acetate species coordinated to copper sites and hydroxylation of nearby surface oxygen sites. For formic acid the decomposition of adsorbed formate species results in desorption of CO2 and CO while, for acetic acid, high yields of ketene are observed at temperature >500 K. Modeling by density functional theory (DFT) confirms the strong interaction of acetic acid with the (3,0;1,1) surface and the spontaneous dissociation into adsorbed acetate and hydrogen atom species, the latter forming an OH-group. In an identified reaction intermediate ketene binds via all C and O atoms to Cu surface sites, in agreement with interpretations from XPS. In the vicinity of the adsorbate the surface experiences a local reorganization into a c(2 × 2) reconstruction. The total computed energy barrier for ketene formation is 1.81 eV in good agreement with the 1.74 eV obtained from TPD analysis. Our experimental observations and mechanistic DFT studies suggests that Cu2O can operate as an efficient catalyst for the green generation of ketene from acetic acid., Swedish Research Council (VR); VR Starting Grant; Knut och Alice Wallenbergs stiftelse; STINT Joint China-Sweden Mobility Program; Ragnar Holm Foundation; Trygger’s Foundation; Chalmers Areas of Advance-Materials Science

Colorectal cancer (CRC) has a poor prognosis and urgently needs better therapeutic approaches. 5-Aminolevulinic acid (ALA) induced protoporphyrin IX (PpIX) based photodynamic therapy (PDT) is already used in the clinic for several cancers but not yet well investigated for CRC. Currently, systemic administration of ALA offers a limited degree of tumour selectivity, except for intracranial tumours, limiting its wider use in the clinic. The combination of effective ALA-PDT and chemotherapy may provide a promising alternative approach for CRC treatment. Herein, theranostic Ag2S quantum dots (AS-2MPA) optically trackable in near-infrared (NIR), conjugated with endothelial growth factor receptor (EGFR) targeting Cetuximab (Cet) and loaded with ALA for PDT monotherapy or ALA/5-fluorouracil (5FU) for the combination therapy are proposed for enhanced treatment of EGFR(+) CRC. AS-2MPA-Cet exhibited excellent targeting of the high EGFR expressing cells and showed a strong intracellular signal for NIR optical detection in a comparative study performed on SW480, HCT116, and HT29 cells, which exhibit high, medium and low EGFR expression, respectively. Targeting provided enhanced uptake of the ALA loaded nanoparticles by strong EGFR expressing cells and formation of higher levels of PpIX. Cells also differ in their efficiency to convert ALA to PpIX, and SW480 was the best, followed by HT29, while HCT116 was determined as unsuitable for ALA-PDT. The therapeutic efficacy was evaluated in 2D cell cultures and 3D spheroids of SW480 and HT29 cells using AS-2MPA with either electrostatically loaded, hydrazone or amide linked ALA to achieve different levels of pH or enzyme sensitive release. Most effective phototoxicity was observed in SW480 cells using AS-2MPA-ALA-electrostatic-Cet due to enhanced uptake of the particles, fast ALA release and effective ALA-to-PpIX conversion. Targeted delivery reduced the effective ALA concentration significantly which was further reduced with codeliver, Newton-Katip Çelebi Fund; British Council; Scientific and Technological Research Council of Turkey (TÜBİTAK)

Here, a facile approach to enhance the performance of solar-driven photoelectrochemical (PEC) water splitting is described by means of the synergistic effects of a hybrid network of plasmonic Au nanoparticles (NPs) decorated on multiwalled carbon nanotubes (CNTs). The device based on TiO2–Au:CNTs hybrid network sensitized with colloidal CdSe/(CdSexS1−x)5/(CdS)1 core/alloyed shell quantum dots (QDs) yields a saturated photocurrent density of 16.10 ± 0.10 mA cm−2 [at 1.0 V vs reversible hydrogen electrode (RHE)] under 1 sun illumination (AM 1.5G, 100 mW cm−2), which is ≈26% higher than the control device. The in-depth mechanism behind this significant improvement is revealed through a combined experimental and theoretical analysis for QDs/TiO2–Au:CNTs hybrid network and demonstrates the multifaceted impact of plasmonic Au NPs and CNTs: i) hot-electron injection from Au NPs into CNTs and TiO2; ii) near-field enhancement of the QDs absorption and carrier generation/separation processes by the plasmonic Au NPs; iii) enhanced photoinjected electron transport due to the highly directional pathways offered by CNTs. These results provide fundamental insights on the properties of QDs/TiO2–Au:CNTs hybrid network, and highlights the possibility to improve the performance of other solar technologies., China Postdoctoral Science Foundation; National Natural Science Foundation of China (NSFC); Natural Science Foundation of Shandong Province; National Key Research and Development Program of China; Ministry of Education, China, 111 Project; UESTC Shared Research Facilities of Electromagnetic Wave and Matter Interaction; Natural Science and Engineering Research Council of Canada; Canada Foundation for Innovation (CFI); Canada Research Chairs Program; UNESCO Chair in MATECSS for a PDF Excellence Scholarship; University of Electronic Science and Technology of China; Fonds de recherche du Quebec Nature et technologies (FRQNT)

A highly sensitive platform is demonstrated for hydrogen gas (H-2) sensing based on a polymer microcylinder ring resonator (PMRR) obtained by an optical fiber coated with an inner nanofilm of amorphous palladium (Pd) and an outer polymer layer of polydimethylsiloxane (PDMS) permeable to H-2. The sensing scheme is based on monitoring the spectral shifts of high-quality optical resonances called whispering gallery modes (WGMs) that propagate in the vicinity of the outer rim of the PDMS layer without being affected by the absorption and scattering losses caused by the Pd nanofilm. WGMs are excited by a single-mode tapered optical fiber evanescently coupled to the PMRR. The observed reversible spectral shifts of the WGMs are induced by changes in the diameter of the PDMS layer caused by expansion or contraction of the Pd nanofilm exposed to varying concentrations of H-2. Maximum spectral shift sensitivity of 140 pm/% H-2, a minimum response time of 95 s, and minimum limit of detection of similar to 60 ppm were measured for sensors prepared with different thicknesses of the amorphous Pd nanofilm and tested in the H-2 concentration range up to 1%, having nitrogen gas (N-2) as a carrier. Experiments were also conducted with Pd nanofilms annealed in air or N-2 atmosphere after the deposition. In both cases, smaller sensitivities were observed due to the formation of larger grains within the film, resulting in slower diffusion and reduced solubility of H in the Pd layer. The impacts of oxygen gas and humidity on sensor performance were also studied., Scientific and Technological Research Council of Turkey (TÜBİTAK)

The initial introduction of new medicinal agents into the health care system sometimes, requires information beyond that is recorded in libraries relying instead, on reports available through traditions and healers within a society. This paper explored the antibacterial activity of aqueous and hydromethanolic extracts of nine folkloric medicinal plant from Bechar region (southwest Algeria) namely: A. nardus, A. schoenanthus, G. vulgaris, two species of H. scoparia green & red, P. laevigata, R. tripartita, T. gallica and T. nudatum, frequently used in the local traditional medicine. The antibacterial activity of different extracts were evaluated by using disc diffusion method agar and antibiotics susceptibility of ten selected microorganisms: seven reference strains, Bacillus cereus, Enterococcus faecalis, Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Salmonella typhi, and three clinically isolated strains, Escherichia coli (Urinary Tract Infection), Escherichia coli (Vaginal Infection) and Staphylococcus aureus (Skin Infection).The maximum antibacterial activity was recorded against the gram negative reference strains Pseudomonas aeruginosaand Escherichia coli with a maximum inhibition diameter of 15.6 ± 0.5 and 15.0 ± 1.4 mm respectively displayed by the aqueous extract of T. gallica, followed by the activity detected by the hydromethanolic extract of R. tripartita against the gram negative reference strain Pseudomonas aeruginosa (14.6±1.2 mm) and the aqueous and hydromethanolic extracts of R. tripartita against the gram negative reference strains Pseudomonas aeruginosa and Escherichia coli with a maximum inhibition diameter of 14.3 ± 2.0 and 14.3±0.5 mm, respectively.According to the present study, H. scoparia red, P. laevigata, R. tripartita, and T. gallicacan be served as broad spectrum antibiotic and used as a potent source of natural antibacterial agents by replacing commercially available synthetic drug that may h

Nanocrystalline spinel copper ferrite CuFe2O4 thin film has been studied and synthesized via the electrodeposition-anodization process. Electrodeposited CuFe2 alloys were obtained from aqueous sulphate bath. The formed alloys were electro oxidized (anodized) in aqueous (1 M KOH) solution, at room temperature, to the corresponding hydroxides. The anodized CuFe2 alloy films were annealed in air at 400 0C for 2 h. The parameters controlling of the electrodeposition of CuFe2 alloys such as the bath temperature, agitation and the current density were studied and optimized. The crystal structure, crystal size and microstructure of the produced ferrites were investigated using X-ray diffraction (XRD) and scanning electron microscopy (SEM). XRD shows that CuFe2O4 had a spinel structure and the crystallite size of CuFe2O4 phase was 2 nm. SEM micrograph of the formed ferrite particles shows agglomeration structure morphology with a narrow distribution of the particles.

Well-defined poly(2-ethyl-2-oxazoline) (PEOX)/Malonic Acid (MA) fibers having hollow tubular morphology were shown to form in aqueous solutions at 25 degrees C by complexation induced self-assembly between PEOX and MA. The fibers had diameter of similar to 1-3 mu m and a wall thickness of -40 nm. Different interactions between PEOX and MA were identified for complexation as a function of pH. At pI-12, when both ends of MA were protonated, H-bonded complexation was the driving interaction in the fiber formation. IR data showed both PEOX -C=0 band and MA -COOH band in dried fibers formed at pH2. The downshift in the -C=0 stretching of PEOX by as much as 15 cm(-1) confirmed the H-bonded complexation. The interaction enthalpy of PEOX and MA was determined by isothermal titration Calorimetry (ITC) as -49.39 kJ/mol which is consistent with H-bonding. Thermogravimetric analysis (TGA) of the fibers showed two distinct decomposition temperatures one between 100 and 150 degrees C corresponding to MA and the other one at 350-450 degrees C corresponding to PEOX which also indicated the presence of both components in the fibers. At pH4, when one end of MA was protonated and the other end was ionized, electrostatic complexation between carboxylate (-COO-) group of MA and the amide group of PEOX was the driving interaction in the fiber formation. At pH7, when both ends of MA were ionized, fiber formation was significantly hindered. The results are important in understanding the role of different interactions in the hollow fiber formation mechanism as a function of pH. pHresponsive hollow fibers have great potential to be used in biomedical applications for drug delivery and release purposes., Scientific and Technological Research Council of Turkey (TÜBİTAK)

The interaction of CO with Pt/3d/Pt(111) subsurface alloys (3d: Ni, Co, Fe) was investigated by combination of vibrational spectroscopy and temperature programmed desorption. The binding strength of CO is significantly reduced on Pt/Fe/Pt(111) and Pt/Co/Pt(111) and is sorted in the following order: Pt >Ni > Co approximate to Fe. Our analysis shows that the 3d admetal is stable in the subsurface region and CO is linearly bonded to the atop sites of the Pt(111) surface. At high CO coverage, compressed structures are obtained. At low CO coverage, the desorption activation energy of CO (similar to 143 kJ/mol for Pt(111)) drops to 124 kJ/mol for Pt/Ni/Pt(111), and goes further down to 111 and 110 kJ/mol for Pt/Co/Pt(111) and Pt/Fe/Pt(111), respectively. The enhancement in the surface activity is attributed to the modified backdonation to the antibonding states of adsorbed CO due to the downshifted 5d-band center of Pt upon embedding 3d metals in the subsurface region., Scientific and Technological Research Council of Turkey (TÜBİTAK); TARLA

The objective was to study the effect of Calamintha officinalis methanolic fraction in the prevention of thrombosis and to explore its effect on primary and secondary hemostasis. The antithrombotic activity was evaluated by using the pulmonary thromboembolism experimental model. Platelet aggregation, tail bleeding time and coagulation assays were explored to elucidate the antithrombotic mechanism. For aggregation, washed platelets were incubated in presence of Calamintha officinalis methanolic fraction and then activated by different agonists (thrombin, ADP, collagen). The bleeding time was determined to measure the time between the tail incision and the moment the bleeding stops. The coagulation was explored by measuring prothrombin time, activated partial thromboplastin time, thrombin time and plasmatic fibrinogen concentration. For ex vivo study, the animals were treated by the Calamintha officinalis methanolic fraction (250 mg/kg/day) for 4 weeks. Then, platelet aggregation, tail bleeding time and coagulation parameters was studied. The results indicate that C. officinalis methanol fraction seems to exert in vivo an antithrombotic action (40% of protection). The in vitro investigations also show that this fraction significantly inhibits aggregation, increases bleeding time, coagulation times and reduces fibrinogen concentration. The chronic treatment of animals confirms the precedent data. This study demonstrates an antithrombotic effect of C. officinalis. The observed antiaggregant and anticoagulant effects could explain this activity.

In this study, we developed a new type of microphotoreactor based on an optofluidic waveguide with aqueous liquid core fabricated inside a nanoporous aerogel. To this end, we synthesized a hydrophobic silica aerogel monolith with a density of 0.22 g cm(-3) and a low refractive index of 1.06 that-from the optical point of view-effectively behaves like solid air. Subsequently, we drilled an L-shaped channel within the monolith that confined both the aqueous core liquid and the guided light, the latter property arising due to total internal reflection of light from the liquid-aerogel interface. We characterized the efficiency of light guiding in liquid-filled channel and-using the light delivered by waveguiding-we carried out photochemical reactions in the channel filled with aqueous solutions of methylene blue dye. We demonstrated that methylene blue could be efficiently degraded in the optofluidic photoreactor, with conversion increasing with increasing power of the incident light. The presented optofluidic microphotoreactor represents a versatile platform employing light guiding concept of conventional optical fibres for performing photochemical reactions., NA

We report the synthesis of copper nanoparticle using a completely green protocol. Aqueous copper sulphate solution was used as a precursor of copper nanoparticle whereas L-ascorbic acid and starch acted as reducing agent and stabilizer respectively. Formation of copper nanoparticle was confirmed by colour, UV-VIS spectroscopy and X-Ray Diffraction (XRD) results. The as-synthesized copper nanoparticles show characteristic plasmonic band at 590 nm. High-Resolution Electron Microscopy (HRTEM) shows almost spherical particles having average diameters of 5.7 ± 1.8 nm. As-synthesized copper nanoparticle exhibits antibacterial activity for both Gm-positive bacteria, Bacilus subtilis and Gm-negetive bacteria, Escherecia coli. Plate count and Minimum Inhibitory Concentration (MIC) studies show higher susceptibility of B. subtilis towards copper nanoparticle

Surface tension measurements have been carried out using lecithin and dodecyl pyridinium chloride separately and in combination, with a view to examine the variation of CMC with composition and to have an estimate of the intermolecular interactions amongst the surfactant molecules. Estimation of the surface excess when the surtactant mixtures of different compositions are used, has also been carried out. The surfactant mixtures exhibit non-ideality in a substantial measure as evidenced by the so-called 'excess surface excess' and the nature of its variation with composition. An attempt has also been made to obtain a quantitative estimate of the interactions on the basis of the regular solution theory.

Adsorption of diethyldithiocarbamate and ethylxanthate on chalcopyrite mineral surface was studied by static bed adsorption method. The qualitative nature of surface species was examined by selective solvent extraction and UV-visible spectroscopic technique. The results clearly indicate that the interaction between surface metal ions and thiols is chemical in nature. As a result of chemical interaction of ligand molecules, metal ions from mineral surface are dislodged from the lattice and precipitates of metal-ligand complexes were formed on the surface, Surface complexes were found to be identical to that of bulk complexes with metal-to-Iigand ratio of 1:2.

The binding constant, K, of [Co(en)3]3+, [CO(II)]2+, [Co(NH3)5Cl]2+, trans-[Co(en)2Cl2]+ and [Co(NH3)3 (NO2)3]0 defined in terms of the partitioning between bulk aqueous phase and micellar pseudophase, using gel filtration chromatography employing Sephadex G-25 fine and sodium dodecylsulphate, SDS. The variation of K with charge types is explained on the basis of the role of both electrostatic and hydrophobic effects.

The surface adsorption of the aqueous solutions of octylalcohol-sodium decylsulfate, n-octylalcohol-decyltrimethyl-ammonium bromide, n-oclylalcohol-decylammoriium bromide mixtures and the surface pressure-molecular area relationships of the mixed insoluble monolayer of octadecylalcohol-sodium octadecyl-sulfate, octadecyltrimethylammonium bromide have been studied. The results show that (1) the surface activity of ionic surfactant, irrespective of whether it is anionic or cationic, is much enhanced by the addition of a small amount of octylalcohol; the surface adsorptions of the two components are mutually enhanced at a dilute solution concentration and depressed near the saturation adsorption; the molecular interaction parameters, Pa of all the binary systems studied have large negative values; (2) the mixed insoluble film of octadecylalcohol-octadecyl trimelhyl-ammonium bromide (or sodium octadecylsulfate) is more condensed than the single component; a negative value of surface excess free energy, Gxs, is obtained. A conclusion has been made: the interactions between alkyl alcohol and ionic surfactant in the adsoiption layer and insoluble monolayer are essentially due to the hydrophobic effect of HC-chain and the ion-dipole interaction between polar heads, and H-bonding is not the determining factor.

The literature on surface micellization or hemimicellization of surfactants at oxide/water interface is reviewed briefly. The adsorption model of cationic surfactant at silica/water interface is described, and a recently proposed approach is introduced which allows determination of nhm the average aggregation number of surfactant ions in a hemimicelle from the adsorption isotherm. The thermodynamics of hemimicelle formation is described which also allows to evaluate the nhm, as well as the free energy of hemimicellization from the adsorption of isotherms.

Water is an integral part of life. Water plays many roles in biological systems. Acid-base balance of the body is primarily maintained by proper urination. Development of pressure, sustenance of pressure and finally release of pressure across urinary bladder membranes is the normal pattern of urination. Passive collection and active expulsion of urine is the primary function of the bladder. Bladder surface should not interact with urine as regards passive collection is concerned. After experiencing certain value of pressure, it begins to interact which finally leads to expulsion of urine with drastic change in polarizability.Use of aquaguard water, aquafina water and cold drinks (Pepsi ,Thums up etc.) are becoming fashion of the modern society. These liquids differ minutely in their physical properties but interactional behavior is quite significant. Hydrodynamic and electro-osmotic permeability measurements of these liquids have been carried out across urinary bladder membranes. Methodology of non equilibrium thermodynamics have been used to explain the data. It has been found that thumsup produces maximum change in polarizability as compared to other permeants.

Silver nanoparticles have been prepared by the reduction of silver ions using respectively castor oil (ricinus communis), khat (catha edulis) and sun flower (helianthus annuus) leaf extracts as reducing and stabilizing agents. The as-synthesized material was characterized by using spectroscopic, XRD and TEM techniques. As-synthesized silver nanoparticles are found to have face centered cubic structure with average crystallite size 28 nm. and showed antimicrobial activity against Escherichia coli and Staphylococcus aureus.

Polyaniline (PANI)-modified glassy carbon electrode has been synthesized by electropolymerizing aniline for determining acetylsalicylic acid (ASA in pharmaceutical samples using cyclic and differential pulse voltammetric techniques. The best performance of the PANI modified glassy carbon electrode in 0.04 M Britton Robinson buffer was obtained at pH 2.0. Under these conditions single oxidation peak at a potential of 250 mV vs Ag/AgCl/sat'd KCl, characteristic of an irreversible reaction, was observed. Studies on the effects of pH, scan rate and substrate concentration revealed irreversible diffusion controlled electrode redox reaction. The PANI modified glassy carbon electrode showed higher electro-catalytic efficiency, compared to the unmodified one, for ASA determination.

An Effective Pair Potential (EPP) theory is used to study relation between the molecular chiral structure of a phospholipid (Dipalmitoyl phosphatidyl choline; DPPC) and the shape of the mesoscopic domain composed of DPPC. It is experimentally known that the monolayers of DPPC in the condensed phase exhibit the formation of triskellion shaped domains. The curvature of the arms of the triskellions has specific handedness depending on the chirality of the constituent molecule. The study uses an equivalent description of the groups attached to the chiral center and calculates the mutual orientation of a pair of molecules (enantiomeric and racemic pairs). The pair potential is calculated using Lennard Jones potential. Also, the electrial interaction is computed using semi-empirical approach. Based on the minimum energy arrangement, the handedness of the aggregates and their pair potential are predicted. Theoretically obtained results are compared with the experimental results and also with the previously obtained coarse-grained description of the molecule. The study uses no adjustable parameter and uses the microscopic information obtained from X-ray diffraction data. It shows that the equivalent sphere description of the molecule can fairly describe the mesoscopic features of the domains such as the handedness based on the pair potential calculation.

ZnS and N-doped-ZnS nanoparticles were prepared by aqueous chemical method under optimal conditions and characterized using XRD, TEM and UV-Visible spectroscopic techniques. As-synthesized nanomaterials were used as a photo-catalysts for the degradation of Methyl Orange (MO) dye. Effects of photo-catalyst load, pH, and substrate initial concentration on degradation of the dye in aqueous solution have been investigated. Maximum degradation (76.56 %) of methyl orange was observed using optimum pH 6 and catalyst load 250 mgL-1.

Synergetically modified nanosize TiO2 semiconductor heterogeneous photocatalyst powder has been synthesized from TiCl4 precursor for producing efficient photocatalyst that may work under visible radiation. The crystallite phase and size of the as-synthesized photo-catalyst were determined by X-ray diffraction (XRD) technique. As-synthesized TiO2 was found to be nano-crystalline anatase. The absorption edge of the photo-catalyst was evaluated from the UV/ Visible diffuse absorbance spectra. The band gap energies (Ebg) of undoped-, Ag-doped-, Ndoped- and Ag-N co-doped TiO2 semiconductor photo-catalysts were found to be 3.14, 3.02, 2.56 and 2.45 eV, respectively. Co-doping of Ag and N in TiO2 has shown synergetic effect towards photo-catalytic degradation of methyl orange in aqueous solutions. Using Ag-N co-doped TiO2 photo-catalyst, degradation of methyl orange under UV and visible irradiations were 79.1% and 73.5%, respectively.

The fluorescence quenching of the dye, Safranine T (ST) by [Fe(CN)6]4-, [Fe(CN)6]3- and Fe2+ in reverse micellar medium of Aerosol OT (AOT) in heptane has been investigated. The ions influence the process to different extents. The process involves collisional quenching. Statistical model has been used to determine the radii of the trapped water in AOT reverse micelles (RM) using the dye as a probe.

The cyanine dyes came to the limelight in 1856 [1] for their application to impart light sensitivity to silver halide emulsions in a region of the spectrum to which the silver halide is normally not sensitive. Numerous applications in various areas are being published every year on this subject. Now it has gained importance for their use in photodynamic therapy and in various biological activities. The generic cyanine dyes consist of two nitrogen centers, one of which are positively charged and are linked by a conjugated chain of an odd number of carbon atoms to the other nitrogen ( 1 ). This has been studied as ?Push-pull? alkenes and forms the basis of the polymethine dyes, which contain the streptopolymethine unit as the chromophore. These dyes are classified as cationic streptopolymethines and hemicyanines ( 1 ), anionic streptopolymethine oxonols ( 2 ), neutral streptopolymethine merocyanines ( 3 ) and zwitterionic squaraine-based cyanines ( 4 ) depending upon the charge of the streptomethine unit. Generally these dyes have an all-trans geometry in their stable form. These dyes undergo photo-isomerization, which can be studied by using various techniques such as flash photolysis, transient absorption, picosecond time-resolved spectroscopy, etc. [2-5]. The cyanines, merocyanines and squaraine dyes are substances with a variety of colors, but are not widely used for dyeing purposes, as they are decolorized by light and acid.

Antimicrobial assay of n-hexane plant extracts against Escherichia coli and Staphylococcus aureus had been done. Extraction with n-Hexane of the flowers yielded 2,08% of extract, while leaves and stems yielded 3,21% and 2,19% of n-hexane extracts, respectively. The extracts showed different activity against both bioindicators. The leaves extracts showed the strongest activity indicated by wider diameters of inhibition zone, 19,7 mm against E. coli and 13,3 mm against S. aureus at 10% of the extracts’ concentration. At the same concentration (10%), the steam and flower extracts showed less inhibitory activities with  11,3 mm and 8,3 mm against E. coli, and 12,0 mm and 11,0 mm against S. aureus. At the lowest concentration of the extracts, the leaves extracts showed the strongest activity against E. coli (14,3 mm) while the steam extracts showed highest inhibitory activity against S. aureus ( 7,7 mm). Based on antimicrobial assay, it was suggested that the leaves extracts demonstrated strongest activity than other extracts. It was assumed that leaves extracts contained more secondary metabolite than flowers and steams, and the leaves have phenol compounds which are not present in other extracts.

Presentation given on research into the use of electrolytes in making safer lithium-ion batteries.

Dissolution-reformation cycle of the passive oxide layer on the nickel-titanium (NiTi) orthodontic archwires was investigated, which has recently been recognized as one of the key parameters dictating the biocompatibility of archwires. Specifically, commercially available NiTi orthodontic archwires were immersed in artificial saliva solutions of different pH values (2.3, 3.3, and 4.3) for four different immersion periods: 1, 7, 14, and 30 days. Characterization of the virgin and tested samples revealed that the titanium oxide layer on the NiTi archwire surfaces exhibit a dissolution-reformation cycle within the first 14 days of the immersion period: the largest amount of Ni ion release occurred within the first week of immersion, while it significantly decreased during the reformation period from day 7 to day 14. Furthermore, the oxide layer reformation was catalyzed on the grooves within the peaks and valleys due to relatively larger surface energy of these regions, which eventually decreased the surface roughness significantly within the reformation period. Overall, the current results clearly demonstrate that the analyses of dissolution-reformation cycle of the oxide layer in orthodontic archwires, surface roughness, and ion release behavior constitute utmost importance in order to ensure both the highest degree of biocompatibility and an efficient medical treatment., Turkish Academy of Sciences (TÜBA) within Outstanding Young Scientist Program (GEBIP); Scientific and Technological Research Council of Turkey (TÜBİTAK) within National Graduate Student Fellowship Program

Today the high demand for electronics leads to massive production of waste, thus green materials based electronic devices are becoming more important for environmental protection and sustainability. The biomaterial based hydrogels are widely used in tissue engineering, but their uses in photonics are limited. In this study, silk fibroin protein in hydrogel form is explored as a bio-friendly alternative to conventional polymers for lens applications in light-emitting diodes. The concentration of silk fibroin protein and crosslinking agent had direct effects on optical properties of silk hydrogel. The spatial radiation intensity distribution was controlled via dome- and crater-type silk-hydrogel lenses. The hydrogel lens showed a light extraction efficiency over 0.95 on a warm white LED. The stability of silk hydrogel lens is enhanced approximately three-folds by using a biocompatible/biodegradable poly(ester-urethane) coating and more than three orders of magnitude by using an edible paraffin wax coating. Therefore, biomaterial lenses show promise for green optoelectronic applications., Marie Curie Career Integration Grant (PROTEINLED); Turkish Academy of Sciences; Scientific and Technological Research Council of Turkey (TÜBİTAK)

LaFexCo(1−x)O3 thin films were prepared on fluorine-doped tin oxide conducting glass substrates by spray pyrolysis without any conductive additives and evaluated for their ability to catalyze the oxygen reduction reaction. Onset potential and current density were found to be comparable to platinum, and the resulting crystallite size was on the order of 20 nm. Coordination of the precursor metal ions by citrate was found not to be advantageous. Results from multiple scan linear sweep voltammetry suggest lattice oxide saturation during reduction of oxygen and lattice oxide depletion upon water oxidation. The color of the best-performing composition changes dramatically between 1.2 and −1.15 V versus saturated calomel electrode, so X-ray photoelectron spectra of the fully oxidized and reduced films were compared, demonstrating that cobalt in the film changes oxidation state. Performance of the films as a function of iron-to-cobalt ratio is consistent with what others have reported in the literature, indicating that spray pyrolysis is an efficient method to prepare and evaluate new catalytic materials., citation/reference: LaFexCo(1–x)O3 Thin-Film Oxygen Reduction Catalysts Prepared Using Spray Pyrolysis without Conductive Additives Dilek Dervishogullari, Christopher A. Sharpe, and Lee R. Sharpe ACS Omega 2017 2 (11), 7695-7701 DOI: 10.1021/acsomega.7b01428, note: This work was supported by Grinnell College Mentored Advanced Project program. The authors also thank Warren Straszheim, Scott Schlorholtz, and Dapeng Jing at the Materials Analysis and Research Laboratory, Iowa State University, for materials characterization and helpful discussions.

Nano-aggregates of N-acetyl-N-carboxymethyl chitosan (NCac) were studied at 0.5 mg.mL-1 using pyrene fluorimetry analysis in 0.1 mol.L-1 phosphate buffer (pH 7.4). The size and morphology of the aggregates were determined by dynamic light scattering and atomic force microscopy. The stability of the particles for periods up to 20 h in buffer was determined. Camptothecin was entrapped in the particles using various methods and the rate constant for drug release (k) was determined. Lower k values indicate strong interactions between the drug and the hydrophobic core of the polymeric micelles.

– In this research bentonite was used as filler to produce polymer electrolyte (PVCLiClO4). Some weight variation of bentonite have been made by addition, such as 0% wt/wt; 5% wt/wt ; 10% wt/wt ; 15% wt/wt ; 20% wt/wt ; and 25% wt/wt of bentonite to the mixture of 0,5 gram of PVC and 0,125 gram of LiClO4. Ionic conductivity of polymer electrolyte was tested using impedance spectroscopy. The result of the research was showed that a mixture of PVCBentonite( 10% wt/wt)-LiClO4 gives the highest ionic conductivity (4,86 x 10-3 S.Cm-1). This result indicated that the presence of natural bentonite can be used as a filler in the current composite polymer electrolyte and can increase the ionic conductivity of the polymer electrolyte.

A series of ten 2,4,6-trisubstituted s-triazines have been synthesized selectively with nucleophilic reagents such as 4-amino benzonitrile, 8-hydroxy quinoline and different piperazine as well as piperidine substituents on the C-6 position of s-triazine ring. The title compounds were then examined for their in vitro microbial activity against 2 gram –Ve bacteria (E. Coli, P. Aeruginosa), 2 gram +Ve bacteria (S. Aerues, B. subtilis) and 2 fungal species (C. Albicans and A. niger). The most of the synthesized compounds have shown potent anti-bacterial and anti-fungal activities. Structure of final scaffolds has been affirmed by means of IR, 1H NMR, 13C NMR and elemental analysis.Keywords: 2,4,6-trichloro-1,3,5-triazine, 8-hydroxy quinoline, 4-amino benzonitrile, anti microbial activity.

No Abstract

Phytochemical screening of P. glutinosa extracts revealed the presence of alkaloids, terpenes, sponins, flavonids, anthraquinone and glycosides. Quantitative determination of total phenolics, total flavonoids, and various in vitro antioxidant activities (DPPH, ABTS metal chelation effect in the Fe2+-ferrozin test system) of the various extracts from the P. glutinosa was carried out. Phenol and flavonoid content of the extract were measured by folin ciocalteu and AlCl3 assays. The Phenol and flavonoid content of the extracts varied between 18.33 – 199.44 mg/g and 14.64 – 164.73 mg/g, respectively. The results showed that the butanol extract of P. glutinosa, which contain highest amount of phenol and flavonoid compounds, exhibited the greatest antioxidant activity in scavenging of DPPH free radical and ABTS radical cation assays. In other hands, results showed that aq. Methanol, butanol and water extracts studied are in metal-chelating assay lower active than EDTA and higher than ascorbic acid as a synthetic antioxidant.

The aim was to determine the possibility of the metal-containing wastes using as a ceramic glaze pigments. In the article the investigations results of the metal-containing wastes coloring properties for ceramic tiles glazes are presented. The research methods. It was studied the coloring properties of the spent catalysts that are used in ammonia production - for medium and low temperature conversion of carbon monoxide and methane conversion catalyst and deposits of metals carbonates that were obtained from spent electrolytes and waste water. The data of the chemical and phase composition of wastes on the results of X-ray diffraction and differential thermal analysis are presented. The samples of ceramic glazed tiles were produced with the using of the wastes. The wastes was fined and added into the ceramic glaze, glazed coating was covered by spraying on ceramic samples and were heat treatment under conditions that was identical to industrial conditions. The burning temperature was 900-1200 ° C. The color and glazed surface quality are controlled according to current standards. The results. It’s found that all tested wastes can create color of ceramic glaze, spent catalysts: medium-temperature conversion of carbon monoxide - brown, spent catalyst of lowtemperature conversion of carbon monoxide - a blue-green, catalyst conversion of methane - gray and gray-brown, cadmium and zincbase carbonate – white, nickel base carbonate – gray, mixture of base carbonate - gray-blue. The scientific novelty. The using not of all waste lets you create high-quality surface. The presence in the spent catalyst low conversion of methane monovalent copper oxide leads to boiling of the glaze. Also the base carbonate mixture that contains calcium carbonate, which decomposes at a temperature close to the temperature of firing ceramic tiles and cause excessive gas formation, which also brings to breach of the surface. It’s recommended use of these, Целью работы было выяснение возможности использования металлосодержащих отходов в качестве пигментов для керамической глазури. В статье приведены результаты исследований красящих свойств металлосодержащих производственных отходов в процессе изготовления керамической глазури для облицовочной плитки. Методики исследований. Для исследований использовались отработанные катализаторы аммиачного производства -низкотемпературной и среднетемпературные конверсии оксида углерода и алюмоникелевий катализатор конверсии метана, а также осадки гидроксокарбонатов металлов, которые были получены из отработанных электролитов и сточных вод. Приведены сведения о химическом и фазовом составе отходов производства по результатам рентгенофазового и дифференциально-термического анализа. С использованием предоставленных отходов было изготовлено образцы керамической глазурованной плитки. Отходы измельчались и добавлялись в состав керамической глазури, глазурованное покрытие наносилось путем пульверизации, керамические образцы проходили термообработку в условиях идентичных производственным. Температура обжига составляла 900-1200 °С. Контролировалась окраска и качество созданной глазурованной поверхности в соответствии с действующими стандартами. Результаты. Установлено, что все апробированые отходы способны создавать окраску керамической глазури: отработанный катализатор среднетемпературной конверсии оксида углерода - коричневую, отработанный катализатор низкотемпературной конверсии оксида углерода - сине-зеленую, катализатор конверсии метана - серую и серо-коричневую, гидроксокарбонаты кадмия и цинка - белую, гидроксокарбонаты никеля - серую, смесь гидроксокарбонатов - серо-голубую. Научная новизна. Использование не всех отходов позволяет создавать качественную поверхность. Наличие в отработанном катализаторе низкотемпературной конверсии метана оксида одновалентной меди, Метою роботи було з’ясування можливості використання металовмісних відходів в якості пігментів керамічної глазурі. В статті наведені результати досліджень забарвлюючих властивостей металовмісних відходів виробництва в процесі виготовлення керамічної глазурі для облицювальної плитки. Методики досліджень. Для досліджень використовувалися відпрацьовані каталізатори аміачного виробництва – низькотемпературної та середньотемпературної конверсії оксиду вуглецю та алюмонікелевий каталізатор конверсії метану та осади гідроксокарбонатів металів, які були одержані з відпрацьованих електролітів та стічних вод. Наведені відомості про хімічний та фазовий склад відходів виробництва за результатами рентгенофазового та диференційно-термічного аналізу. З використанням наданих відходівбуло виготовлено зразки керамічної глазурованої плитки. Відходи подрібнювалися та додавалися до складу керамічної глазурі, глазуроване покриття наносилось шляхом пульверизації, керамічні зразки проходили термообробку в умовах ідентичних виробничим. Температура випалу складала 900-1200 °С. Контролювалось забарвлення та якість створеної глазурованої поверхні згідно діючих стандартів. Результати. Встановлено, всі апробовані відходи здатні створювати забарвлення керамічної глазурі: відпрацьований каталізатор середньотемпературної конверсії оксиду вуглецю – коричневе, відпрацьований каталізатор низькотемпературної конверсії оксиду вуглецю – синьо-зелене, каталізатор конверсії метану – сіре та сіро-коричневе, гідроксокарбонати кадмію та цинку – біле, гідроксокарбонати нікелю – сіре, суміш гідроксокарбонатів – сіро-блакитне. Наукова новизна. Використання не всіх відходів дозволяє створювати якісну поверхню. Наявність у відпрацьованому каталізаторі низькотемпературної конверсії метану оксиду одновалентної міді призводить до скипання глазурі. Також суміш гідроксокарбонаті