Predicting Young's Modulus of Glasses with Sparse Datasets using Machine Learning

Machine learning (ML) methods are becoming popular tools for the prediction and design of novel materials. In particular, neural network (NN) is a promising ML method, which can be used to identify hidden trends in the data. However, these methods rely on large datasets and often exhibit overfitting when used with sparse dataset. Further, assessing the uncertainty in predictions for a new dataset or an extrapolation of the present dataset is challenging. Herein, using Gaussian process regression (GPR), we predict Young's modulus for silicate glasses having sparse dataset. We show that GPR significantly outperforms NN for sparse dataset, while ensuring no overfitting. Further, thanks to the nonparametric nature, GPR provides quantitative bounds for the reliability of predictions while extrapolating. Overall, GPR presents an advanced ML methodology for accelerating the development of novel functional materials such as glasses.Comment: 17 pages, 5 figure

PAHs Biodegradation by Locally Isolated Phanerochaete chrysosporium and Penicillium citrinum from Liquid and Spiked Soil

In the present study, biodegradation of polycyclic aromatic hydrocarbons (PAHs) was examined using two fungal strains, namely P. chrysosporium and P. citrinum, isolated from locally contaminated soil. These two fungal strains were compared based on degradation properties under standardized conditions (pH 7.0, temperature 30oC, carbon source yeast extract) using PAH sole and a mixture of five different PAHs. In liquid media, PAH degradation was higher as compared to spiked soil by P. chrysosporium, followed by P. citrinum. In liquid culture, maximum degradation was 96.13% phenanathrene, 86.34% fluoranthene, 72.75% pyrene, 52.25% chrysene, and 40.16% benzo(a)pyrene by P. chrysosporium. PAH degradation in spiked soil was 78.5% phenanthrene, 65.91% fluoranthene, 61.73% pyrene, 48.2% chrysene, and 26.82% benzo(a)pyrene within 28 days by P. chrysosporium. Both local fungal isolates showed potential for degradation of PAHs alone and in PAH mixtures

Structural, optical, and dielectric properties of A[(Mg0.32Co0.02) Nb0.66]O3 semiconductor, where (A = Ba, Sr or Ca)

Structural optical and dielectric properties of single phase A[(Mg0.32Co0.02) Nb0.66]O3, where A = Ba, Sr, or Ca, compounds were studied in the temperature range from room temperature (293 K) to 458 K. The X-ray diffraction revealed that the Ba[(Mg0.32Co0.02)Nb0.66]O3 [BMCN] compounds exhibit hexagonal symmetry whereas Sr[(Mg0.32Co0.02)Nb0.66]O3 [SMCN] and Ca[(Mg0.32Co0.02)Nb0.66]O3 [CMCN] compounds exhibit monoclinic symmetry. The replacement of Barium (r = 1.61 Å) by smaller ions like Strontium (r = 1.44 Å) or Calcium (r = 1.34 Å) in the polar dielectric Ba[(Mg0.32Co0.02) Nb0.66]O3 introduces the relaxation phenomenon and a gradual increase in the transition temperature maximum (Tm). The ac conductivity, as determined from the dielectric data, as a function of temperature and frequency, reveals the crossover from small polaron tunneling (SPT) to correlated barrier hopping (CBH) type conduction at » 370 K. The activation energy of the non-Debye type process evaluated both from the electric modulus and the conductivity data are nearly identical suggesting similarity in the hopping mechanism. The band gap of these materials lies in the range of narrow to wide band semi conductors. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/2206

Enhanced visible fluorescence in highly transparent Al-doped ZnO film by surface plasmon coupling of Ag nanoparticles

ZnO:Al (AZO) film has been deposited on quartz substrate by Pulsed laser deposition and showed monophasic hexagonal structure of c-axis oriented nanorods upto 80 nm in height. AZO film was optimally conjugated with Ag nanoparticles (Ag NPs) in a hybrid nanostructure to achieve significant enhancement in the visible fluorescence emission. Augmented near field and extinction spectra of shape tailored Ag NPs and their dimers are simulated through FDTD method, and a direct association with fluorescence enhancement is established. Such plasmon-enhanced visible emission from a transparent conducting oxide could be very important for solar cell applications

Effect of storage temperature and duration on sugar content and sensory acceptability of strawberry pulp

Experiment was conducted to study the effect of different treatments on preservation of strawberry pulp at ambient and low storage temperature condition. The samples were pasteurized at 100°C for 15 minutes (T1), sodium benzoate 250 ppm (T2) and sodium benzoate 500 ppm (T3). The respective samples were stored for two months at room (25±5°C) and low (7±2°C) temperature conditions and reducing sugars; total sugar and sensory evaluation were recorded at three days of interval period. The results showed that the total sugar (%) increased in pulp sample maximum in T6 (5.9%) and minimum in T1 (4.8%), the maximum value regarding reducing sugars was recorded in T6 (4.9%) and minimum in T1 (1.4%) after 60th days of storage. However, reducing sugars and total sugar decreased in the stored pulp at room temperature and spoiled completely on 18th day of storage. The acceptability of organoleptic score decrease with the duration of storage in both ambient and low temperature. Among different treatments, sodium benzoate @ 500 ppm was found most effective and maintained the qualitative characteristics of preserved pulp at low (7±2°C) temperature condition. In future, these experimental results may prove very useful for storage of strawberry pulp for longer duration in better quality