Thermal and electrical effects of basbars on Li-Ion batteries

Keeping temperature under control is critical for batteries to work effectively. When the safe operating range is exceeded, both the lifetime of batteries decreases and undesirable situations may occur such as fire. In this study, the effects of basbars on battery modules are examined. It is shown that the most intense current transitions pass through the shortest path connecting the batteries. When the distance between the batteries is increased, cooling is effective and the temperature of the batteries is expected to decrease. However, this is not the case in our study. It is observed that the temperature of the battery modules increases due to the increased length of the basbar. For this reason, it is emphasized that basbars are a parameter that cannot be ignored with respect to the temperature of battery modules. In this study, six different materials (ie, silver, copper, gold, nickel, steel and titanium) are used as basbars when trying to achieve the best results. For each basbar material, the maximum temperature values and discharge curves reached by the battery module are found. The results suggest that silver is the best basbar material. For the silver material, the temperature distributions of the battery modules, the maximum temperature value received by the module and the discharge curves are found for different C ratios.     

Illumination and voltage effects on the forward and reverse bias current–voltage (I-V) characteristics in In/In2S3/p-Si photodiodes

Journal of Materials Science: Materials in Electronics - The illumination and voltage effects on the I-V measurements of the fabricated In/In2S3/p-Si photodiode were investigated in dark and under...     

Determination of calcium in milk and water samples by using catalase enzyme electrode

A biosensor based on catalase enzyme was developed for the investigation of the effect of calcium ions on the activity of the enzyme. Calcium plays an activator role for the catalase enzyme that catalyses the degradation of hydrogen peroxide to O₂ and H₂O. Determination method of the effect of calcium ion on the activity of the enzyme was based on the assay of the differences on the responses of the biosensor in the absence and the presence of calcium in the reaction medium. The biosensor had a linear relation to calcium concentrations and good measurement correlation between 1 and 10 mM with 1 min response time. Tris–HCl buffer (pH 7.0; 50 mM) and 37 °C were obtained as the optimum working conditions. In the application studies, the biosensor was used determination of calcium level of real samples such as milk, spring and mineral water.     

Experimental and theoretical study on catalytic ozonation of humic acid by ZnO catalyst

Ozonation and catalytic ozonation of humic acid (HA) in the presence of ZnO were examined in a batch scale reactor. The degradation of HA by catalytic ozonation was found to be much more effective than ozonation alone. The quantum chemistry calculations showed that the reaction of the O₃ disproportionation on the surface of ZnO corresponds to the barrierless mechanism. The activation energy of the transition state formation was ?5.25 eV. The active oxygen atom formed on the surface of ZnO was found as interacting with both water molecules and dissolved organic molecules, which might lead to further oxidizing reactions.     

Innovative Carbon Dioxide‐Capturing Organic Solvent: Reaction Mechanism and Kinetics

The reaction rates of CO₂ with an innovative CO₂‐capturing organic solvent (CO₂COS), consisting of blends of 2‐tert‐butyl‐1,1,3,3‐tetramethylguanidine (BTMG) and 1‐propanol, were obtained as function of BTMG concentration and temperature. A stopped‐flow apparatus with conductivity detection was used. The reaction was modeled by means of a modified termolecular reaction mechanism which resulted in a second‐order rate constant, and activation energies were calculated for a defined temperature range. Quantum chemical calculations at the B3LYP/6‐31G(d) level also produced the activation energy of this reaction system which strongly supports the experimental findings.     

Usage of enzymes in a novel baking process

In this study, the effects of different enzymes (alpha-amylase, xylanase, lipase, protease) on quality of breads baked in different ovens (microwave, halogen lamp-microwave combination and conventional oven) were investigated. It was also aimed to reduce the quality problems of breads baked in microwave ovens with the usage of enzymes. As a control, bread dough containing no enzyme was used. Specific volume, firmness and color of the breads were measured as quality parameters. All of the enzymes were found to be effective in reducing the initial firmness and increasing the specific volume of breads baked in microwave and halogen lamp-microwave combination ovens. However, in conventional baking, the effects of enzymes on crumb firmness were seen mostly during storage. The color of protease enzyme added breads were found to be significantly different from that of the no enzyme and the other enzyme added breads in the case of all type of ovens.     

A study on the effects of different gums on dielectric properties and quality of breads baked in infrared-microwave combination oven

In this study, the effects of different gums on dielectric properties of doughs and breads baked in infrared-microwave combination oven were investigated. In addition, the quality parameters of breads formulated with different gums baked in infrared-microwave combination oven were determined. The gums used were xanthan, guar, xanthan-guar blend and κ-carrageenan. The gums were added to the formulation at 0.5% concentration. The dielectric properties and quality parameters of breads baked in infrared-microwave combination oven were found to be dependent on gum type. κ-carrageenan resulted in undesirable final bread quality, while xanthan-guar blend addition improved bread quality (high specific volume and porosity, low hardness values). The dielectric properties of bread samples formulated with κ-carrageenan were found to be the highest among the other gum types.     

Oxidation States and the Acidity of Ordered Arrays of Co–Pb Mixed Oxide Nanoparticles Templated in SBA15

Co, Pb and CoPb containing SBA15 mesoporous materials were prepared by direct synthesis method. When Co and Pb were loaded simultaneously, nanoparticles were formed in the channels of SBA15 as observed by transmission electron microscopy. These nanoparticles blocked the pores and decreased the apparent surface areas indicated by BET analysis. Pyridine adsorption on these catalysts revealed that while monometallic additions did not influence the overall acidity of SBA15, in the bimetallic system, characteristic bands due to pyridine adsorption on Co²⁺ ions were observed.     

Kinetics of Carbon Dioxide Binding by Promoted Organic Liquids

The reaction kinetics of carbon dioxide and CO₂‐binding organic liquids (CO₂BOLs) promoted by piperazine (PZ) and its derivatives were investigated experimentally by stopped‐flow conductimetry. The study was carried out at 298 K and for a concentration range of 0–0.25 kmol m^?3 of PZ, 1‐(2‐aminoethyl)piperazine (AEPZ) or 1‐(2‐hydroxyethyl)piperazine (NHEPZ) while the superbase (1,1,3,3‐tetramethylguanidine or 1,8‐diazabicyclo[5.4.0]undec‐7‐ene) concentrations were kept constant at 10.0 wt %. Based on pseudo‐first‐order reaction conditions, the intrinsic reaction rate data were analyzed according to a modified termolecular reaction mechanism. The results showed that the rate of reaction between CO₂BOLs and CO₂ could be significantly enhanced by blending with small amounts of PZ, NHEPZ or AEPZ as promoters.