Search

Inorganic filler manufactured for incorporation into thermoplastic elastomers usually are surface treated with organic reagents in order to improve the interfacial adhesion between filler and the matrix. In the present paper, the effects of acrylic acid (AA) on tensile and morphology properties of wollastonite (WS) filled high density polyethylene (HDPE)/Natural Rubber (NR) composites were studied. The untreated and treated HDPE/NR/WS composites were melt-blending at 180 °C with rotor speed of 50 rpm for 10 minutes. The composites were tensile-tested according to ASTM D638 and the etched surfaces were observed using scanning electron microscope (SEM). Tensile strength and elongation at break of the compositesdecreased upon the addition of wollastonite, but Young's modulus improves. The results of this study showed that the treated composites are found to have better tensile properties than the untreated composites. The morphology of treated composite showed better interfacial interaction between HDPE/NR and wollastonite.

Peroxide enzymes are widely used as a reagent in many clinical diagnosis of analysis methods such as ELISA, immunoblotting, and immunochemistry. Water spinach ( Ipomea aquatica Forssk) is a species of plant available abundantly in Indonesia, hence it is a potential source of peroxidase. In this study, the crude extract of water spinach leaves was known to contain peroxidase enzyme which was active toward hydrogen peroxide. A fraction of extract yielded from differential fractionation using ammonium sulfate at concentration 40-65% (F4) was known to be the most active. Characterization of specific activity of peroxidase of F4 for optimum pH and temperature was at pH 5 and 60 °C. The Michaelis-Menten constant (Km) was 0,27 mg/mL and enzyme's catalytic rate (Vmax) was 2,16 mg/mL/min.

Oxidative stress is believed as underlined mechanism of exercise induced muscle damage. This study was aimed to investigate curcuminoid effect on protein oxidation and lipid peroxidation muscle of exercised induced model. Adult male healthy mice were used as experiment models, grouped in to curcuminoid treated, placebo (corn oil only treated) and untreated group. Protein carbonyl level was significantly lower in curcuminoid treated group compared with untreated group (p =0.003). In the contrary, the malondialdehyde level was not significantly different between those groups (p = 0.092).

An alternative technology of benzene alkylation with propylene is proposed at OJSC Omsk rubber. The effectiveness of aluminum chloride catalyst replacement is evaluated on sulfocationites. A discrete supply of propane-propylene fraction to the alkylation reactor is proposed. The mathematical model of benzene alkylation process with propylene using the sulfocationites catalysts was developed. Mathematical model of the process was developed in the program environment AspenTech. The numerical values of the rate constants were determined. An adequate process model allow carrying out numerical experiments on the variation of the basic reagents relations reactions.

The porous structure of nanoparticles of copper-cadmium oxide system prepared by AC electrochemical synthesis in sodium chloride with a concentration of 3, 15, 25 wt. % has been studied. The obtained data indicate that at a higher current density and sodium chloride concentration of 3% wt. in the electrochemical oxidation of cadmium and copper products are formed with the structure of mesopores and channels. In this case, the specific surface area has the greatest value (19.4 m2/g) and a maximum pore volume (0.0778 cm3/g). Thus, the obtained data allow predicting the operating parameters of the electrolysis to obtain a copper - cadmium oxide system of a predetermined porous structure.

The aim of this study was to evaluate the bioactivity response of alumina (Al2O3) coated scaffold for bone tissue engineering (BTE) applications. The porous alumina (alumina foam, AF) was coated with hydroxyapatite (HA), with bentonite (Al2O3.4(SiO2).H2O) as an intermediate layer between HA and alumina. Bentonite acted as binding agent to improve the alumina-HA coating, with hope that excellent coating with HA will have a positive effect on subsequent cellular efforts, with alumina responsible for just the scaffold strength. In brief, AF has been fabricated with acceptable properties (i.e., porosity >80%, compressive strength >3 MPa, average pore size of 900-1000 μm) through polymer foam replication (PFR). After AF fabrication, initially, the AF was dipped into HA slurry and sintered at 1300 °C to make HA coated AF (HACAF) scaffold. Due to poor uniformity of HA coating on the AF, the alumina foam was first dipped into bentonite slurry and sintered at 800 °C before coated with HA, creating HA-bentonite coated AF (HABCAF). It was shown that with an inner-coat of bentonite (on AF), the HA coating was smoother, more uniform and more complete/thorough. The in-vitro degradability was conducted using simulated body fluid (SBF) as a preliminary study to evaluate bioactivity response for each sample (i.e., AF (as control), HACAF, HABCAF). The weight loss of the HACAF is quicker compared to HABCAF and are seen increased with longer soaking time. The ions particle precipitations were found on surface layer after 7 days for coated alumina compared to alumina skeleton. The result suggested that HABCAF offers an attractive option for fabrication of BTE scaffolds.

Flame retarded poly(lactic acid)/poly(methyl methacrylate) (PLA/PMMA) blend was prepared using melt compounding technique in the presence of isopropylated triaryl phosphate ester flame retardant [FR; 20 parts per hundred resins (phr)]. The effect of FR on the thermal and flame resistant properties of PLA/PMMA blend was studied. The flammability of PLA/PMMA blends was evaluated by UL-94 vertical burning test while the morphology of the residues was analyzed using field emission scanning electron microscope (FESEM). Thermogravimetric analyzer (TGA) was utilized to characterize the thermal decomposition behaviors of PLA/PMMA blends. The UL-94 result revealed that the inclusion of FR has shorten the after-flame time and improved dripping behavior of PLA/PMMA blend, achieving V-0 ranking in the test. An extensive and continuous carbonaceous char-like layer was found on the surface of the PLA/PMMA/FR residue, indicating the existence of condensed phase mechanism by FR. The incorporation of FR has accelerated the thermal degradation of PLA/PMMA blend at low temperature, but enhanced thermal stability of the blend at elevated temperature.

The Eastern Sumatran peat swamp ecosystem is one of the most threatened and most poorly understood biotypes. Until recently, there is no scientific record concerning ichtyoplankton composition within this system and all fish's biodiversity research at this ecosystem relied on morphological diagnosis for adult stages. Two new fish records in this system, Rasbora pauciperforata and Ompok eugeneiatus were detected. Finally the authors concluded that, eleven fish species complete their life history in Eastern Sumatran peat swamp. This investigation enlarges the COI barcode database for the molecular identification of eastern Sumatran peat swamp fishes.

Combustion of the rice husk produces rice husk ash, which consists of mainly silica. High purity silica can be produced by controlled combustion after acid treatment. In this study, leaching of rice husk with hydrochloric acid and sulfuric acid were carried out prior to combustion to obtain purer silica. It was found that pre-treatment of the rice husk with sulfuric acid had accelerated the hydrolysis and decomposition of organic components as revealed by thermogravimetry (TG) and Scanning Electron Microscopy (SEM) analyses. In a systematic study, the combustion of un-leached, hydrochloric acid-leached and sulfuric acid-leached rice husks were performed in a muffle furnace at 500, 600, 700, 800 and 900oC for 2 h. Results demonstrated that all the samples produced amorphous silica (SiO2) and the average particle size were in the range of 0.50 to 0.70 μm. The effect of combustion at different temperatures between 500oC and 900oC on the silica production is very small, particularly at temperature above 600oC. Thus, amorphous silica with purity above 99% as confirmed by X-Ray Fluorescence (XRF) analysis can be produced by hydrochloric and sulfuric acids leaching of the rice husk, followed by controlled combustion at 600oC for 2 h. The BET surface area of the silica produced after leaching the rice husk with hydrochloric acid was higher (218 m2/g) than with sulfuric acid (209 m2/g). The silica obtained has potential application as filler in plastics and rubber compounding.

Hepatitis C Virus (HCV) has infected approximately 2-3% (130-170 million) of the world's population. No vaccine is available to prevent HCV infection. Investigation of anti-HCV agent is thus deemed necessary. Various plants have been explored for their anti-HCV activity. A. serratus is a member of Sapindaceae family, which fruit and seed were traditionally used as insecticide. Anti-HCV activity tested on A.serratus leaves extract has been done. The result showed that leaves extract exhibited anti-HCV with IC50 value of 14.9μg/ml and 9.8μg/ml against HCV J6/JFH1 and JFH1a, respectively. The cytotoxicity assay results showed that A.serratus leaves extract was not toxic and has CC50 >100μg/ml. Mode of action experiment results suggested that A.serratus extract inhibited HCV at the post-entry step. Further fractionation of leaves extract by open column chromatography resulted in 4 fractions. Only Fraction 1 (AP-5F.1) exhibited anti-HCV with IC50 value of 1.2μg/ml against HCV JFH1a. Separation of AP-5F.1 by open column chromatography resulted in 15 fractions. Fraction number 13 (AP-5F.1.13) exhibited anti-HCV with IC50 value of 0.43μg/ml against HCV JFH1a. Separation of AP-5F.1.13 by semi preparative-HPLC resulted in isolate identified by TLC and LC-MS method as chlorophyll derivate. There was a possibility that chlorophyll derivate has participated in performing the anti-HCV activity of fractions and extract besides the other compounds contained. In this study, we concluded that A. serratus leaves extract, AP-5F.1, and AP-5F.1.13 exhibited anti-HCV activity against JFH1a virus.

In this study, Linear Alkyl Sulfonate (LAS) as anionic detergent active compounds was treated with photocatalytic method. The method degrades LAS to form CO2 and H2O. Time variations performed to the photocatalysis was conducted hour to hour, from 1 to 5 hours. Determination of LAS concentration was carried out using methylene blue active substances (MBAs), whereas characterization of LAS structure was observed using high performance liquid chromatography (HPLC) and nuclear magnetic resonance spectrometry (NMR). The results showed that 69.9% of LAS decomposes 65.1% of CO2 are formed.

The anti-inflammatory effect caused by VNN infection in the grouper fish using pigment-protein fraction of N.oculata has studied. Methods were to explore the pigment-protein fraction of N.oculata, in vivo test, and measurement of anti-inflammatory response using dot blott and immunohistochemistry technique. Results indicate that pigment-protein fraction of N. oculata was able to suppress grouper tissue inflammation when VNN infection was occurring. Inflammation sign was reduced by administration of pigment-protein fraction. This reaction was reinforced by raising of expression of TNFα and IL-6, which means that TNFα and IL-6 acts as an anti-inflammatory in fish tissue.

The experimental data for hydrogenation of sulfur compounds including benzothiophenes (BT) and dibenzothiophenes (DBT) in the diesel fuel with 1.4 mass% of sulfur content is obtained using the laboratory setup with the aluminum-cobalt-molybdenum catalyst GKD-202 at the pressure of 3.5 MPa and different temperatures. The sulfur compound removal factor reaches 98 mass%. Dynamics of DBT and BT concentrations allowed designing a kinetic model represented by the system of differential equations of individual sulfur compound rates. The kinetic model was included in the developed software. The basis of the algorithm for reverse kinetic problem solution is the method of scanning through predefined range of constants. This enables performing the calculation with an error not exceeding 0.007%. The obtained data confirmed that chemical activity increases in the order: DBT, BT, sulfides. The rate of desulfurization decreases with increase in alkyl substituents concentrations. DBT desulfurization is much worse than the one of BT. The calculated data allowed building the graphs representing BT and DBT concentration dynamics.

CoRe4 catalysts highly active for ammonia synthesis at ambient pressure and 400°C can be prepared without an ammonolysis stage. Pre-treatments under 3:1 H2:N2 and 3:1 H2:Ar atmospheres are shown to influence catalytic performance with the latter treatment leading to an induction period prior to development of activity upon switching to an ammonia synthesis feedstream. The difference in behaviour between the two pre-treatment atmospheres is manifested in temperature programmed nitrogen isotopic exchange experiments where H2:Ar treated material is inactive and its H2:N2 treated counterpart is active.

Sm-Art is a project dedicated to collectivity and to culture’ liberalization by using social media tools. It's a business project interested in offering integrated services dedicated to culture promotion through the creation of a cultural social network with social, economic and innovative-technological aims. Tuke is its first product: a cultural social network which aims to create a virtual community in order to promote dialogue, encourage debating and motivate collaboration for a participated sense of culture and cultural heritage promotion and the enhancement of the people’ sense of belonging to its territory.

The effect of pyrolysis rate on the properties of alginic acid-derived carbonaceous materials, termed Starbon®, was investigated. Thermal Gravimetry-IR was used to prepare porous carbons up to 800°C at several rates and highlighted increased CO2 production at higher pyrolysis rates. N2 porosimetry of the resultant carbons shows how pyrolysis rate affects both the mesopore structure and thus surface area and surface energy. Surface capacity of these carbons was analysed by methylene blue dye adsorption. In general, as the rate of pyrolysis increased, the mesopore content and adsorbent capacity decreased. It is considered here that the rapid production of volatiles at these higher rates causes structural collapse of the non-templated pore network. The work here demonstrates that pyrolysis rate is a key variable which needs to be controlled to maximise the textural properties of Starbon® required for adsorption applications.

This paper reports the study carried out on the 18th century painted silk panels that cover the walls of the so called Salotto delle sete dipinte in Palazzo Barberini at Rome on the occasion of the conservation work started in 2007. Microscope and spectroscopy investigations were performed in order to study the materials and the realization techniques of the painted silk panels and to evaluate the conservation conditions. Moreover ageing tests were performed in order to evaluate the stability of the consolidant/protective product used for the silk panels.

The selection of a solvent or a solvent system is a fundamental and a crucial step in spinning fibres using a selected process. Solvent selection determines the critical minimum polymer concentration and the critical minimum chain entanglement which allows the spinning of nanofibres rather than other hybrid morphologies such as beaded structures. Pressurised gyration, which simultaneously combines the use of gas pressure and rotation, is used as the processing and forming route for spinning fibres in this work. This study investigates 23 different solvents and solvent systems spread on a wide area of a Teas graph and able to dissolve the functional polymer polyethylene (terephthalate) (PET) and spin products by the application of pressurised gyration. The results are mapped on a Teas graph to identify the solubility–spinnability region. Based on this solubility–spinnability region, various solvents and binary solvent systems that allow the making of PET fibres are suggested. Scaling laws for the relationship between polymer concentration and specific viscosity are identified. The structural evolution in the fibres prepared is elucidated. For the first time, a mathematical model to scale fibre diameter with respect to flow properties and processing parameters encountered in pressurised gyration has been successfully developed.

In this research, multi-walled carbon nanotubes buckypaper have been incorporated into three-ply glass fiber/epoxy laminated composites to form hybrid composites. Two different type of MWCNT buckypaper have been incorporated into glass fiber/epoxy laminated composites. The buckypaper incorporated were either in form of free-standing MWCNT buckypaper (CNTBP) or MWCNT buckypaper/epoxy (CNTBPE). The effect of the incorporation of the buckypaper in the hybrid composites have been compared to three-ply and four-ply glass fiber/epoxy laminated composites. It was found that CNTBPE sample exhibits 50% and 30% higher flexural strength compared to three-ply glass fiber composite and four-ply glass fiber composite, respectively. Specific strength and specific modulus of the CNTBPE samples reached up to64.03 MPa/gcm-3and 6.43 GPa/gcm-3, respectively. The specific strength and modulus of CNTBPE is 70 and 30%, respectively higher compared to 3GF. This showed that incorporation of MWCNTBP/epoxy in the glass fiber composite system promotes the fabrication of lightweight structures with better flexural strength properties.

Substantial efforts have been made globally towards improving Cu(In,Ga)Se 2 thin film solar cell efficiencies with several organisations successfully exceeding the 20% barrier on a research level using the three-stage CIGS process, but commercial mass production of the three-stage process has been limited due to the technological difficulties of scaling-up. An attempt has been made to identify these issues by designing and manufacturing an in-line pilot production deposition system for the three-stage CIGS process which is capable of processing 30 cm × 30 cm modules. The optimisation of the process parameters such as source and substrate temperature, deposition uniformity, flux of copper, indium, gallium and selenium and thickness control has been presented in this investigation. A simplistic thickness distribution model of the evaporated films was developed to predict and validate the designed deposition process, which delivers a comparable simulation compared with the experimental data. These experiments also focused on the optimisation of the temperature uniformity across 30 cm × 30 cm area using a specially designed graphite heating system, which is crucial to form the correct α-phase CIGS in the desired time period. A three-dimensional heat transfer model using COMSOL Multiphysics 4.2a software has been developed and validated with the help of experimental data.

The behavior of filler particles in the polymer matrix on a physical model representing the suspension of solid particles in the apolar liquid has been studied. Relative sedimentation volumes of powder components included in the polymer composition for the cable insulation in liquids of different polarity have been identified. The dependence of the effect of hygroscopic powder fillers on the relative sedimentation volume of powders and a ratio of wetting has been studied. It has been found that hydrophobic interactions are not observed at the surface of completely dry materials placed in liquids of different polarity. Consequently, the role of the filler is actually to prevent adsorption of moisture from the air on the surface of the particles, to reduce their hygroscopicity. It is proposed to assess the degree of water-repellency of the particles of powdered fillers by the measurement of their maximum hygroscopicity.

Thioureas are important sulfur and nitrogen containing compounds and they are useful substances in drug research. In an effort to improve potential anticancer activities, two novel 1-benzoyl-3-methyl thiourea derivatives were designed and synthesized with substitution at aromatic positions of C-3, and C-4 of 1-benzoyl-3-methyl thiourea. Their structures were confirmed using IR, MS and 1 H-NMR. The in vitro cytotoxicity against HeLa cell lines were evaluated by the standard MTT assay. All of the compounds exhibited more potent cytotoxicity with IC50 values of 160–383 μg/mL stronger than hydroxyurea with IC50 value of 428 μg/mL.

Cymbopogon winterianus Jowitt or citronella is said to be an insect repellant and usually planted in the yard in the Philippines. In this study enzymatic extracts of citronella were fractionated using supercritical carbon dioxide extraction to have different oil extracts in three different parameters, 10 megapascal (10 MPa), 20 megapascal (20 MPa) and 30 megapascal (30 MPa) at constant temperature at 40° Celsius. The highest oil yield is at 20 MPa with an average of 10.21 for three trials of extraction, followed by 10 MPa and 30 MPa with 4.89 and 2.15. Oil extract at 10 MPa was subjected to gas chromatography- mass spectrometry (GC-MS) and found four components in which 2-methyl-5-(1-methylethyl)bicycle hexan 2-ol or trans sabinene hydrate and 4-methanol-o-Menth-8-ene or elemol was the major compounds. The pure crude enzymatic extract, 20 MPa and 30 MPa supercritical carbon dioxide extracts were subjected to fatty acid profiling, twelve free fatty acid were found at pure crude enzymatic extract, while nine free fatty acid were found at 20 MPa and 30 MPa supercritical carbon dioxide extracts. Lauric (C12) is consistently highest in terms of weight by weight in three extracts that were subjected to free fatty acid profiling. This study can be used as basis for agricultural applications in food and pharmaceutical since there is no thorough study of the fractionation of enzymatic extract of citronella.

Initial cell evaluation on alginate/hydroxyapatite block was investigated. Sodium alginate with 1, 3 and 5% concentration was obtained via neutral extraction of locally obtained brown seaweed, Sargassumpolycystum. Commercially available hydroxyapatite (HAp) powder was pressed uniaxially at 3 MPa to obtain the HAp block. The HAp block was then sintered at 900C. The sintered HAp block was then immersed in the sodium alginate solution at different concentration for 24 hours under vacuum condition. Morphological observations show that normal cell growth was observed on alginate/HAp blockafter post treatment for day 1 and 2. However, the cell starts to show some distinct morphological changes when compared to the control cells for day 5 and 7. Cell viability assay results shows that a consistent cell growth was obtained with HAp block incorporated with 3 and 5% sodium alginate. While HAp block without the incorporation of sodium alginate and HAp block incorporated with 1% sodium alginate concentration shows inconsistent cell growth. Initial cell evaluation results suggest that alginate/HAp block shows no toxicity on cell attachment and proliferation.

Due to its ecological benefits, bamboo is considered as attractive material. Recently, conventional bamboo modification in industry consumes time and chemicals. Supercritical fluid technology contributes to overcome these disadvantages. This process was performed in a batch impregnation with a statistical method. In this study, durability tests over a period of 32 weeks confirm that acetylated (un)-extracted bamboos regarded as durable material with mass loss ratio median (X) of 0.24-0.25. Additional the results of water sorption isotherm and the fibre saturation points are illustrated, as well as the crystallinity index.

Stereoselective total syntheses of (±)-aphidicolin and (–)-serofendic acids A and B have been achieved by means of palladium-catalyzedcycloalkenylation.

While it is well-known that supersaturated cubic-structured Ti1−xAlxN can be prepared by physical vapor deposition, the impact of point defects on formation process and cubic to wurtzite transition is largely unexplored. Irrespective of point defects, ab initio calculations correctly predict the Al concentration of the cubic to wurtzite transition. By means of density functional theory we show that vacancies on metal and/or non-metal sites only slightly affect the cubic to wurtzite transition region, whereas they clearly affect the physical properties., Highlights • No significant impact of vacancies on the cubic to wurtzite transition in Ti1−xAlxN • Explanation of agreement of experiment and simulation despite negligence of vacancies • Impact of vacancies on phase stability of metastable Ti1−xAlxN • Influence of vacancies on lattice parameter and elastic properties in Ti1−xAlxN

The identification of interdicted nuclear or radioactive materials requires the application of dedicated techniques. In this work, a new approach for characterizing powder of uranium ore concentrates (UOCs) is presented. It is based on image texture analysis and multivariate data modelling. 26 different UOCs samples were evaluated applying the Angle Measure Technique (AMT) algorithm to extract textural features on samples images acquired at 250× and 1000× magnification by Scanning Electron Microscope (SEM). At both magnifications, this method proved effective to classify the different types of UOC powder based on the surface characteristics that depend on particle size, homogeneity, and graininess and are related to the composition and processes used in the production facilities. Using the outcome data from the application of the AMT algorithm, the total explained variance was higher than 90% with Principal Component Analysis (PCA), while partial least square discriminant analysis (PLS-DA) applied only on the 14 black colour UOCs powder samples, allowed their classification only on the basis of their surface texture features (sensitivity>0.6; specificity>0.6). This preliminary study shows that this method was able to distinguish samples with similar composition, but obtained from different facilities. The mean angle spectral data obtained by the image texture analysis using the AMT algorithm can be considered as a specific fingerprint or signature of UOCs and could be used for nuclear forensic investigation.

An experimental method of pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) is proposed to evaluate the fate of selected flavour compounds in low-temperature (300 °C) tobacco heating conditions. The thermal behaviour of five flavouring compounds (citronellol, menthol, tartaric acid, cinnamic acid, and guaiacol) was studied under conditions to simulate low-temperature tobacco heating at 300 °C, and compared with results obtained using simulated cigarette-combustion conditions with a temperature programme up to 900 °C. The impact of oxygen and nitrogen atmospheres on the thermal transfer and breakdown patterns was also investigated. It was established that the four flavouring compounds of high volatility (citronellol, menthol, cinnamic acid, and guaiacol) evaporated to a high degree (88–100%) during the low- and high-temperature experiments, as well. Guaiacol was the most stable compound under the test conditions; only 0.3% decomposition was detected at 900 °C with the oxidative atmosphere. Thermal decomposition reactions were substantially less extensive at the low-temperature heating conditions than with the high-temperature pyrolysis and simulated cigarette combustion. Citronellol and cinnamic acid produced about 1.5% decomposition products, while menthol produced 0.8%. In general, dehydrogenation reactions were more pronounced in the oxidative atmosphere, while aromatisation was significant in the nitrogen atmosphere, and at high temperatures. More oxo-compounds and less aromatic hydrocarbons were formed in the oxidative atmosphere. Other types of reactions took place with tartaric acid, due to its low volatility. Extensive formation of light carboxylic acids was observed at the low temperature, and cyclic compounds were also formed in addition to carbon oxides and water under both nitrogen and oxidative atmospheres. Intermolecular reactions are proposed to explain these observations. At high temperatures the pyrolysis products of tartaric acid were the same as at low temperatures, but in the oxidative atmosphere more carboxylic acids and less aldehydes were formed than in pure nitrogen. These results demonstrate the flavour compound’s thermal stability depends strongly on the exact thermal history (heating temperature, heating duration and gas atmosphere) that they are exposed to. The information obtained will be of interests in understanding the thermal behaviour of these and other flavour compounds used in tobacco heating products.

All-oxide model-composite electrodes were established consisting of a thin, micropatterned, electronically conducting oxide, which acts as a current collector, and a thin film of gadolinia-doped ceria, which is an electrochemically highly active mixed conductor under reducing atmospheres. The choice of the current collecting oxides was based on their electronic conductivity assessed by measurements of thin films using the van der Pauw method. Lanthanum and niobium doped strontium titanate as well as alumina doped zinc oxide, were investigated this way in a humid hydrogen atmosphere. Promising materials were incorporated as a current collector into model-composite microelectrodes and tested for their stability and efficiency in electrochemically activating the microelectrode. Alumina doped zinc oxide, while being an excellent electron conductor, showed severe stability problems at temperatures above 600°C. However, a microelectrode with a current collector of niobium doped strontium titanate (Sr0·9Ti0.8Nb0·2O3) performed comparable to an electrode with a Pt current collector and, additionally, showed an improved tolerance to sulphur poisoning in a humid hydrogen atmosphere with 10ppm of hydrogen sulphide.

Layers of Nd-doped lead zirconate titanate (PZT) with Ag/Pd electrodes were stressed by DC voltage at about 500 °C. Under field, a black “color” front, visible in dark-field optical microscopy, moved from the cathode into the PZT. The PZT layer became highly conducting after some time but degradation was localized to a near-surface zone and could be removed mechanically, leaving an insulating core bulk zone of PZT with the color front still visible. The time-dependent motion of this color front and the electrical properties of the insulating PZT core bulk zone were investigated upon field and during subsequent relaxation. The results suggest that a redistribution of lead vacancies and built-up of space charge zones at grain boundaries with oxygen vacancy accumulation cause the blackening and conductivity changes. Density of states (DOS) and optical absorption spectra were obtained from density functional theory (DFT) based calculations for several defects in PZT and show that blackening is expected for an increased oxygen vacancy concentration.

Dialkyldithiocarbamates have long been used as chelating agents in solvent extraction of transition metals. In our previous study, an alkyl homolog of this type of ligand, namely dihexyldithiocarbamate (DHDTC), was synthesized and characterized. The use of this particular ligand in the extraction some selected transition metal ions is now reported for the first time. The effect of pH, of the metal to the ligand mole ratio, and of the variation in organic solvents, in the extraction of Fe 3+ , Ni 2+ , Cu 2+ , Cd 2+ , and Zn 2+ , were investigated. Results of the experiments showed that an extractability of about 44.62%, 58.15%, and 61.69%, respectively for Ni 2+ , Zn 2+ , and Cd 2+ at pH 8 could be achieved. For Cu 2+ and Fe 3+ at pH 5 (69.96%) and pH 9 (81.29%). The metal to the ligand mole ratio for divalent transition metal, was 1:2 while trivalent was 1:3.

Turmeric (Curcuma longa L.) is currently considered a potential source of new drugs for a variety of diseases due to the presence of curcuminoids, the most important being curcumin. The existence of genetic diversity in turmeric is documented in other countries but not in the Philippines, where turmeric is an introduced species. This study aims to determine the possible existence of genotypic diversity among turmeric accessions in Mindanao, Philippines using random amplified polymorphic DNA (RAPD) markers. Ten random primers were used for RAPD analysis from which a total of 209 amplification products were generated. Almost all the bands generated were polymorphic indicating genetic diversity among the accessions. Six primers (OPD08, OPB07, OPA11, OPA12, OPC05 and OPN16) had polymorphic information content values of almost 0.5, thus, were able to discriminate between the turmeric genotypes. Effective multiplex ratio and marker index were also relatively high for the same six markers except for OPA12.

Prethrombin-2 recombinantproduction in E. coli still facesa bottle neck due to formation of inclusion bodies. The level of gene transcription can be regulated by using appropriate concentration of IPTG inducer. This study was aimed to determine the effect of isopropyl-β-D-thiogalactopyranoside (IPTG) concentration on prethrombin-2 expression. The prethrombin-2 expression was induced by various concentrations of IPTG at 12 o C hosted by E. coli ER2566. The result show that the suitable IPTG concentration for induction ofprethrombin-2 was 0.010 mM. It was indicated fromthe 63-kDa protein band obtained from the soluble fraction on SDS-PAGE. The higher concentrations of IPTG increased the amount of protein in the insoluble fraction due to the increased of expression rate. It concluded that the IPTG concentration affect the rate ofprethrombin-2 expression.

Gadung (Dioscorea hispida Dennst) tuber contains dioscorin, an alkaloid with high angiotensin converting enzyme-inhibitory cap acity. In this research, dioscorin was extracted using microwave assisted extraction (MAE). The objectives of this research w ere to investigate the influence of ethanol concentration (75 % to 96 % w/w), solvent-material ratio (10 : 1 to 20 : 1) and m icrowave power (100 W to 400 W) on the extraction yield, and to develop a mathematic model to represent that process. The opt imum condition for this process was extraction using 85 % aqueous ethanol at solvent-material ratio of 12.5 : 1, and m icrowave power of 100 W for 20 min. The mathematic model agreed well with the experim ental data with average error of 2.96 %.

In this paper, composite reverse osmosis (RO) membranes made from sulfonated poly(arylene ether sulfone) containing amino groups (aPES) and hyper-branched aromatic polyamide-grafted silica (HBP-g-silica) were prepared, with the aim of enhancing chlorination resistance and improving membrane performance. The performance of the RO membranes containing aPES and HBP-g-silica was evaluated; the salt rejection and water flux were 96% and 34 L/m 2 /h, respectively. After the chlorination test, the salt rejection decreased by only 14% and the water flux increased by 4 L/m 2 /h. The aPES/HBP-g-silica significantly modified the three-dimensional polyamide (PA) network structures and contributed to the high performance because of the chain stiffness of the copolymer with a high degree of cross-linking in the RO membranes. Therefore, the aPES and HBP-g-silica, which helped improve water permeability, also protected the active layer structure from degradation and enhanced the chlorine resistance of the RO membrane.

Chitosan has been widely used as an edible coating for extending the shelf life of fruit. In this research, chitosan was applied to Cavendish banana. The effect of different degree of deacetylation (DD) of chitosan (70%, 80%) in various chitosan concentration (1, 1.5, 2% w/w) in solution on weight loss and vitamin C loss were investigated. The effect of the presence of emulsifier triethanolamine (TEA) was also examined. Sensory analyses were conducted to monitor the changes in color, texture, and aroma. The results showed that coated banana fruit demonstrated delayed ripening processes compared to the uncoated banana. This also confirmed by the reduction in weight loss as well as in vitamin C loss in comparison to the uncoated banana. Weight loss and vitamin C loss decreased with increasing chitosan concentration and degree of deacetylation of chitosan. The addition of TEA emulsifier was not significantly influence the weight loss and vitamin C loss. In summary, 2% (w/w) chitosan with DD of 80% was proved to be the most suitable coating among the others for reducing the weight loss and vitamin C loss. loss, and desirable sensory analysis.

This paper outlines the results of analysis of Low-Density Polyethylene (LDPE) depositions on filter elements of upstream II cascade compressor by means of X-ray and Fourier transform infrared spectroscopies, gel permeation chromatography and viscometry, differential scanning calorimetry and 13C NMR spectroscopy. Based on comparison with experimental data of process designers the supposition has been given to the cause of the formation.

In this study, proteases have been isolated from halophilic bacteria, Pseudomonas stutzeri BK AB-12. The bacteria produced proteases as exhibited by the appearance of clear zones resulted from casein hydrolysis. Based on the protease specific activity, 70−80% ammonium fraction exhibited the highest activity. Protease in this fraction has highest activity at pH 8.0 and 55 °C and its activity of protease was enhanced by the addition of several metal ions. The addition of Fe3+ ion also resulted in a shifting of the optimum pH from 8 to 9 and the optimum temperature from 55 to 60 °C. Protease of P. stutzeri BK AB-12 in the fraction of 70−80% is not likely metallo-, cysteine-, or serine-protease because it is not inhibited by EDTA, β-mercaptoethanol, and PMSF. Proteases of this fraction was sensitive to ionic strength, where the highest activity was observed at concentrations at NaCl concentrations of 2.5 M. Beside influenced by the ionic strength, protease activity was also sensitive to solvent polarity. The protease wasstable in the presence of different organic solvents, which enables its potential use for the synthesis of peptides.

The catalytic activities of four types of Co/ZSM-5 zeolites in partial oxidation of methane were compared to observe the effect of pore size and cobalt species to the reaction. Two types of ZSM-5 structures: microporous and hierarchical; and two ways of Co loading: impregnation and ion exchange were studied. The catalytic test was performed at 423 K in a batch reactor (volume c.a. 200 cm3) with methane to N2 ratio of 0.5:2, and 0.5 g Co/ZSM-5 catalyst. The results show that the partial oxidation of methane was selective to methanol production for all four ZSM-5 zeolites. The hierarchical Co/ZSM-5 showed to give the highest conversion of methane to methanol.

Due to its cleanliness, fast energy cycle, and convenience of energy conversion, hydrogen has been regarded as the new energy source. Conventional process to produce hydrogen yield large amount of CO as byproduct. Moreover, the hydrogen storage and transportation have become the drawbacks in hydrogen economy. Thus, there has been increased interest in the hydrogen transportation medium as alternatives from the conventional process to produce and transport hydrogen. Ammonia has drawn worldwide attention as the most reliable hydrogen transportation medium. Through the decomposition of ammonia, hydrogen and nitrogen gas were produces as the byproduct without any CO or CO2 emission. In this experiment, the ore were introduced as the medium for ammonia decomposition. The ore were put into quartz tube reactor and were dehydrated at 400 °C for 1 hour, then hydrogen reduced for 2 hours before and undergone ammonia decomposition at 500-700 °C for 3 hours. The effects of temperature to the % conversion of ammonia decomposition were also studied. Ammonia decomposition at higher temperature gives higher conversion. As seen in the results, the NH3 conversion decreased with increasing time and the value after 3 hours of reaction increased in the sequence of 500 °C

This present study investigates application of supercritical fluid carbon dioxide extraction (SCFE-CO 2 ) for removing fats from black-eyed pea ( Vigna unguiculata ) and peanut ( Arachis hypogaea ) to produce high protein-low fat diet products. SCFE-CO 2 process used Taguchi's orthogonal array at three parameters in three levels: pressures between 25-35 MPa, temperatures between 40-60 °C and CO 2 flowrates between 10-20 g/min. The results of the experiment showed that the optimum conditions of SCFE- CO 2 process were 25 MPa, 60 °C, 10 g/min for black-eyed pea and 35 MPa, 60 °C, 15 g/min for peanut. The highest yield for black-eyed pea and peanut were 5.4% and 48.5%, respectively.

Spirulina is one of the microalgae containing nutrients used as functional food and in theraupetic (active compound). Bioactive compound in Spirulina has antihyperglycemic activity or antidiabetes activity. Diabetes mellitus is a major health problem in the world. The research about the potential of microalgae as antihyperglicemic is important to do. The cultivation of microalgae was conducted in laboratory using flask and aquarium completed with non-stop aeration. Measurement of the antihyperglycemic activity in-vivo using mices that were fed with biomass containing Spirulina fusiformis Voronikhin and phycocyanin. Blood glucose levels were measured by methods of oral glucose tolerance test after a fasting period of 18 h. Oral administration of biomass and phycocyanin of Spirulina fusiformis V. at 0.15 mg · g–1 and 0.30 mg · g–1 proved to decrease the blood glucose level.

Keladi tikus (Typhonium flagelliforme (Lodd) Blume is a plant that has many benefits in - health such as anticancer, anti-inflammatory, analgesic and antihepatotoxic. This study aims to determine the antibacterial and antioxidant activity of different extracts of leaves T. flagelliforme. The agar diffusion method used in the antibacterial activity; DPPH, the FTC and the TBA method used in the antioxidant activity. The results showed the ethyl acetate, n-butanol and water fraction had antibacterial activity against Bacillus subtilis and Pseudomonas aeruginosa, while the n-hexane fraction had no activity against bacteria tested. The results of antioxidant activity by DPPH method, the FTC and the TBA showed ethyl acetate fraction was the most active (IC50 = 56.32 ppm) fraction among others.

The effect of calcination temperature on the properties of CaCu3Ti4O12 (CCTO) ceramics was studied. CCTO ceramics were prepared using solid state reaction method. The raw materials of CCTO were wet mixed for 24 hours and was dried overnight. CCTO powders were then calcined at three different temperature which is at 900̊C, 930̊C and 985̊C for 12 hours. The calcined powders were compacted at 250 MPa and then were sintered at 1040̊C for 10 hours. X-Ray Diffractometer (XRD) analysis showed the formation of CCTO phase and secondary phases of CuO for C900 calcined powder but single phase of CCTO was obtained by C930 and C985 calcined powders. Single phase of CCTO also were seen for all sintered samples. Observation on Scanning Electron Microscopy (SEM) micrographs showed abnormal grain growth or large grain size was seen in C900 sample and finer grain size was observed for C930 and C985 sintered samples. C900 sintered sample obtained the highest dielectric constant (10,462) and the lowest dielectric loss (0.061) measured at 1 MHz.

The analysis of the cracking products of bitumen Karmalskoye deposits (the content of fractions boiling up to 200 °C 6,7% wt.) has been performed. The influence of power plant coal ash microspheres on orientation of cracking bitumen components is stated. Bitumen cracking leads to significant yields of gas and coke for more than 20% wt. and destructions of all components. The initiated bitumen cracking in the presence of 10% microspheres at cracking temperature 450 °C leads to reduction of gas and coke yields and increase in fractions of ibp (initial boiling point) –360 °C at 10% wt. in comparison with products of the thermal bitumen cracking. The analysis of composition and amount of sulfur compounds in initial bitumen and the cracking products in the various conditions has shown that the thermal cracking leads to increased homologues benzothiophene contents due to partial destruction of resins, and to decrease in the content of homologues dibenzothiophene.

In this paper the L-glutamate electrochemical behavior on a carbon-containing electrode modified with gold in simulated solutions by cyclic voltammetry have been studied. The analytical signal of glutamate reduction at the potential of -0.8 V in pH 9.19 has been found. It has been determined that the cathodic reduction of glutamate is irreversible and mainly controlled by diffusion in the reduction electrode process of glutamate. The conditions for glutamate determination in simulated solutions by voltammetry have been found. The plots of current versus concentration present a linear behavior from 3.2·10 -4 to 2.5·10 -3 M. The detection limit is 4.4 10 -5 M. The glutamate determination in simulated solutions has resulted in acceptable deviation from the stated concentration where relative errors are -2.7 to +2.6%.

The researches on the choice of aryldiazonium tosylate salts as a modifier to create an organo-modified electrode were carried out. It is shown that the best organic modifier for surface modification of a mercury-graphite electrode is aryldiazonium tosylate without a substituent. A method for producing an organo-modified electrode and the procedure for measuring the analytical signal of manganese by voltammetry was developed. The method is simple to implement and allows avoiding the use of metal mercury for forming the electrode, and making measurements without aerating of electrolyte by inert gases (nitrogen, argon) with an error (Sr) of not more than 10%.

Eleutherine americana Merr., a medicinal plant, which has been widely cultivated in South East Asia. Ethnobotanically, the plant is known for treating coronary abnormality. Other pharmacological investigations showed its potency as antimicrobial and anti-inflammatory agents, and also as inhibitors of α-glucosidase, HIV replication,and topoisomerase II. Phytochemically, three groups of compounds have been isolated i.e. naphthalene, naphtoquinone and anthraquinone. This review highlights recent data on biological activities and discusses strategies for developing the plant into a more valuable commodity