System identification and control using adaptive particle swarm optimization

This paper presents a methodology for finding optimal system parameters and optimal control parameters using a novel adaptive particle swarm optimization (APSO) algorithm. In the proposed APSO, every particle dynamically adjusts inertia weight according to feedback taken from particles’ best memories. The main advantages of the proposed APSO are to achieve faster convergence speed and better solution accuracy with minimum incremental computational burden. In the beginning we attempt to utilize the proposed algorithm to identify the unknown system parameters the structure of which is assumed to be known previously. Next, according to the identified system, PID gains are optimally found by also using the proposed algorithm. Two simulated examples are finally given to demonstrate the effectiveness of the proposed algorithm. The comparison to PSO with linearly decreasing inertia weight (LDW-PSO) and genetic algorithm (GA) exhibits the APSO-based system’s superiority.     

Preparation and Characterization of Carbon Nanotubes Supported Ni2P for Hydrodesulfurization (HDS) of Naphtha

Abstract

Ni₂P nanoparticles supported by functionalized carbon nanotubes (CNTs) were prepared for the first time. Nickel (II) dihydrogenphosphite as a source of nickel, with different loadings on the functionalized CNTs, were used. The prepared samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy (FT-IR) techniques. Surface areas of the samples were measured by using Brunauer, Emmett and Teller (BET) method. The catalytic activity of the prepared samples was studied in hydrodesulfurization (HDS) of naphtha. The results showed that the CNTs were

functionalized and Ni₂P particles were dispersed on the functionalized CNTs. It was also indicated that the pores size of Ni₂P particles were less than 20 nm. The catalytic study of the prepared samples confirmed that these compounds were stable and active in the process. Removal of sulfur from the desired naphtha in presence of the samples depended on the nickel loadings and increased with temperature in all cases.     

Development and evaluation of a novel nucleic acid sequence-based amplification method using one specific primer and one degenerate primer for simultaneous detection of Salmonella Enteritidis and Salmonella Typhimurium

Salmonella Enteritidis and Salmonella Typhimurium are the most widespread causes of salmonellosis and gastrointestinal diseases worldwide. Thus, their simple and sensitive detection is significantly important in biosafety and point-of-care diagnostics. In that regard, although present nucleic acid-based attempts are mainly focused on the detection methods encompassing all Salmonella enterica members in a single reaction, serotypes other than S. Enteritidis and S. Typhimurium are clinically and epidemiologically rare to humans. Therefore, regarding high ribosomal RNA (rRNA) copy numbers in a cell, isothermal nucleic acid sequence-based amplification (NASBA) technique was employed for simple, sensitive and simultaneous detection of the bacteria. However, due to high sequence homology among 16S rRNA genes and consequently, very few specific regions, we developed a novel NASBA method called “single specific primer-NASBA or SSP-NASBA” in which the specificity of the antisense primer is sufficient to perform a specific NASBA reaction. Accordingly, we designed highly specific NASBA antisense and degenerate sense primers for a segment of 16S rRNA variable region by universal sequence alignment to simultaneously detect S. Enteritidis and S. Typhimurium. Meanwhile, the approach was successfully evaluated for various Salmonella as well as closely related non-Salmonella serovars. Specific and simultaneous detection of both bacteria was achieved with the designed primer set in a single reaction environment with a detection limit of less than 10 CFUs mL⁻¹. The developed NASBA assay should facilitate the overall process and provide a simple, fast, specific and sensitive approach for molecular diagnostics of pathogens under various circumstances, e.g. outbreaks.     

Three-Component Reaction of Triphenylphosphine,Dialkyl Acetylenedicarboxylate,and 2-Aminothiazole or 2-Aminobenzothiazole in the Presence of Arylglyoxals: An Efficient One-Pot Synthesis of Highly Functionalized Pyrroles

A new and efficient one-pot synthesis of polysubstituted pyrrole derivatives by three-component reaction of dialkyl acetylenedicarboxylates, triphenylphosphine, 2-aminothiazole or 2-aminobenzothiazole in the presence of arylglyoxals is described. The reactions were performed in dichloromethane at room temperature and neutral conditions and afforded good yields of products.     

Synthesis and Characterization of Biosuperabsorbent Based on Ovalbumin Protein

A biosuperabsorbent (Bio-SAP) hydrogel from ovalbumin (egg protein) was synthesized via modification with an acylating reagent and a bifunctional crosslinker, and its swelling behavior was investigated. The protein was acylated using ethylenediaminetetraacetic dianhydride (EDTAD), and then crosslinked by glutaraldehyde and dried. Bio-SAP provided through this method includes modification of lysyl residues in the unfolded protein by adding one or more hydrophilic carboxyl groups to increase the hydrophilicity of protein. The water binding capacity was measured in deionized water, 0.9% NaCl solution and synthetic urine, which under the best conditions were 296, 64 and 56 g/g after 24 h, respectively. In addition, the effects of EDTAD/protein ratio on the chemical modification of the protein, the various chemical neutralization agents, pH sensitivity and ionic strength, as well as temperature and particle size on the water absorption capacity with and without load and its kinetic were also investigated.     

A cyclometalated diplatinum complex containing 1,1′-bis(diphenylphosphino)ferrocene as spacer ligand: Antitumor study

Cyclometalated platinum(II) complex [Pt(C^N)Cl(dmso)], 1, in which C^N = N(1),C(2′)-chelated deprotonated 2-phenylpyridine and dmso = dimethylsulfoxide, was reacted with 1 equiv of 1,1′-bis(diphenylphosphino)ferrocene, dppf, to give the cyclometalated diplatinum(II) complex [Pt₂(C^N)₂Cl₂(μ-dppf)], 2, along with 0.5 equiv of unreacted dppf. However, the related reaction with 0.5 equiv of dppf produced complex 2 in pure form. Complex 2 in solution was fully characterized by using multinuclear NMR spectroscopy (¹H, ¹³C, ³¹P, and ¹⁹⁵Pt) and a number of 2D NMR experiments. The structure of complex 2 in solid state was determined by X-ray crystallography showing that the bridging dppf ligand is arranged close to “antiperiplanar staggered” conformation. Cytotoxicity of the complex 2 was studied in three human cancer cell lines derived from ovarian carcinoma(CH1), lung carcinoma(A549), and colon carcinoma (SW480) by means of the MTT assay (MTT = 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide).     

Synthesis of water dispersible boron core silica shell (B@SiO<Subscript>2</Subscript>) nanoparticles

Water dispersible boron nanoparticles have great potential as materials for boron neutron capture therapy of cancer and magnetic resonance imaging, if they are prepared on a large scale with uniform size and shape and hydrophilic modifiable surface. We report the first method to prepare spherical, monodisperse, water dispersible boron core silica shell nanoparticles (B@SiO₂ NPs) suitable for aforementioned biomedical applications. In this method, 40 nm elemental boron nanoparticles, easily prepared by mechanical milling and carrying 10-undecenoic acid surface ligands, are hydrosilylated using triethoxysilane, followed by base-catalyzed hydrolysis of tetraethoxysilane, which forms a 10-nm silica shell around the boron core. This simple two-step process converts irregularly shaped hydrophobic boron particles into the spherically shaped uniform nanoparticles. The B@SiO₂ NPs are dispersible in water and the silica shell surface can be modified with primary amines that allow for the attachment of a fluorophore and, potentially, of targeting moieties.

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