Aggregation mechanism of bovine serum albumin based on collision factor by the population balance conservation law

This paper discusses a novel approach for exploring the aggregation mechanism of bovine serum albumin using collision factor. The population balance equation consisting of aggregation term was developed and solved by the moment method. Different experiments were implemented to account for effective parameters on protein aggregation and to measure variations in average size of aggregates formed in a time interval. This was done by taking pictures with a CCD camera on a sterio microscope. The pictures were exported to image processing software to analyze average number and size of aggregates. The collision factor appearing in population balance equation was optimized and declared as a global term.     

A note on task assignment of several problems

In the last two decades several papers have appeared in the literature where the multi-resource generalized assignment problem (MRGAP) was used to solve different problems. In these problems the number of variables grew exponentially. The purpose of this technical note is to present an assignment model that is compact and includes the models in the previous research papers as special cases. The proposed model is a generalization of MRGAP (GMRGAP). Computational experiment with CPLEX is presented to test effectiveness of the proposed model compared to some existing ones.     

Non-affine nonlinear adaptive control of decentralized large-scale systems using neural networks

This paper introduces a new decentralized adaptive neural network controller for a class of large-scale nonlinear systems with unknown non-affine subsystems and unknown interconnections represented by nonlinear functions. A radial basis function neural network is used to represent the controller’s structure. The stability of the closed loop system is guaranteed through Lyapunov stability analysis. The effectiveness of the proposed decentralized adaptive controller is illustrated by considering two nonlinear systems: a two-inverted pendulum and a turbo generator. The simulation results verify the merits of the proposed controller.     

Surface modification of silica-graphene nanohybrid as a novel stabilizer for oil-water emulsion

The surface modification of silica-graphene nanohybrid through treatment with a mixture of nitric and sulfuric acid vapors to prepare a novel stabilizer for decalin-water emulsion was investigated. The nanohybrid was prepared through chemical vapor deposition using silica aerogel and acetylene as catalyst and carbon precursor at atmospheric pressure and 600 °C. The physicochemical properties of the modified nanohybrid were characterized by FT-IR, XPS, Raman spectroscopy, and TEM. The surface modification of nanohybrid was at various duration times (24, 48, and 72 hours) to optimize the surface modification conditions. Zeta potential of ?39.9 mV revealed that the surface modification of nanohybrid after 72 hours had an excellent stability in aqueous phase due to the presence of exceptional functional groups. The emulsion average droplet size decreased by increasing the nanohybrid concentration. The negative value of the zeta potential showed the proposed nanohybrid can be applied as an appropriate stabilizer for emulsion.     

Optimization of extraction process of bioactive compounds from Bene hull using subcritical water

Bene hull contains antioxidant components. Optimum conditions for bioactive compound extraction processes from Bene hull using subcritical water with response surface methodology (RSM) were obtained. Temperature (110–200°C), processing time (30–60 min), and the water to Bene hull ratio (10:1–50:1) were the investigated factors. The optimal conditions for maximizing the antioxidant activity were 196.8°C for 52.6 min and a ratio of 43.6:1 for water to Bene hull. Under these conditions, the amount of polyphenolic compounds, the reduction power (RP) (EC₅₀), and the DPPH free radical scavenging activity (RSA) (EC₅₀) were predicted to be 2,284 mg of gallic acid/100 g of Bene hull, 0.2002 mg/mL, and 0.6284 mg/mL, respectively. HPLC analysis was used to identify the main phenolic compounds. The subcritical water extraction technique could be used as a beneficial method to obtain bioactive compounds from Bene hull.     

Doping effects of Co on exo-hydrogenated narrow single-walled carbon nanotubes

Density functional theory (DFT) calculations with the generalized gradient approximation (GGA) were employed for a systematic study of electronic structure and morphologic characteristics of bare and exo-hydrogenated Co-doped single walled carbon nanotubes (CNTs). Two internally and one externally doping configurations for the cobalt adatoms were investigated. Binding energies, bond lengths and angles, under full and half converge of the adsorbed hydrogen atoms were calculated for both cases. Effect of hybridization between the Co-3d and the H-s orbitals showed that the exo-hydrogenated CNTs with full and half coverage cases would be stable in the internally doped Co atom systems; whereas, the stability of the hydrogenated systems under externally doped Co adatom was not trivial. In general, for the externally Co-doping, the Co atoms can act as additional adsorbents so the amount of total adsorbed hydrogens could be varied substantially; whereas, for the internally Co-doping the nature of the exo-hydrogenation (being atomic or molecular) shows nanotube's chirality dependent.     

Enhanced geometrical superresolved imaging with moving binary random mask

In this paper, we address the geometrical resolution limitation of an imaging sensor caused by the size of its pixels yielding insufficient spatial sampling of the image. The spatial blurring that is caused due to inadequate sampling can be resolved by placing a two-dimensional binary random mask in an intermediate image plane and shifting it along one direction while keeping the sensor as well as all other optical components fixed. Out of the set of images that are captured, a high resolution image can be decoded. In addition, this approach allows improved robustness to spatial noise.