Thin-layer drying characteristics of sweet potato slices and mathematical modelling

The effect of blanching and drying temperature (50, 60 and 70°C) on drying kinetics and rehydration ratio of sweet potatoes was investigated. It was observed that both the drying temperature and blanching affected the drying time and rehydration ratio. The logarithmic model showed the best fit to experimental drying data. The values of effective moisture diffusivity and activation energy ranged from 9.32 × 10⁻¹¹ to 1.75 × 10⁻¹⁰ m²/s, and 22.7–23.2 kJ/mol, respectively.     

Synthesis and Screening Antimicrobial Activities of Novel 1,3-Diaryl-3- (Phenylthio)Propan-1-One Derivatives

Abstract

In this study, a series of novel β-mercapto carbonyl derivatives (3a–j) was prepared by addition of thiophenol (2) to chalcones (1a–j) in the presence of catalytic amount of iodine (10 mol%) in CH₂Cl₂. Antibacterial and antifungal in vitro properties of the synthesized compounds were tested against some human pathogenic microorganisms by employing the disk diffusion technique. For the most active compounds, also minimum inhibitory concentrations (MICs) were determined.

Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.     

The role of 60Co γ-ray irradiation on the interface states and series resistance in MIS structures

The effect of γ-ray exposure on the metal–insulator–semiconductor (MIS) structures has been investigated using the electrical characteristics at room temperature. The MIS structures are irradiated with ⁶⁰Co γ-ray source. The energy distribution of interface states was determined from the forward bias I–V characteristics by taking into account the bias dependence of the effective barrier height and ideality factor. The value of series resistance decreases with increasing dose. Experimental results confirmed that γ-ray irradiation have a significant effect on electrical characteristics of MIS structures.     

Electrical transport mechanism in boron nitride thin film

Both dc and ac transport characteristics of plasma enhanced chemical vapor deposited (PECVD) boron nitride (BN) thin film was investigated by dc current vs. dc voltage measurement at different temperatures and admittance vs. gate voltage at various frequencies/temperatures, respectively. MIM ≡ metal (Al)-insulator (BN)-metal (Al) or MIS ≡ metal (Al)-BN-semiconductor (p-Silicon) test devices were conventionally produced. Both conductivity anisotropy and dc/ac detailed transport mechanism were analyzed within the frame of a turbostratic structure (t-BN), interfacing the substrate by a thin amorphous layer (a-BN). This defective BN film has been justified by both infrared (IR) analysis and indirectly by the resulting electrical transport behavior. Transport and its variations as a function of temperature/frequency are in agreement with a hopping mechanism across Gauss-like energy distributed localized deep traps.     

Synthesis and characterization of new (N‐diphenylphosphino)‐isopropylanilines and their complexes: crystal structure of (Ph2P S)NH?C6H4?4?CH(CH3)2 and catalytic activity of palladium(II) complexes in the Heck and Suzuki cross‐coupling reactions

Three new (N‐diphenylphosphino)‐isopropylanilines, having isopropyl substituent at the carbon 2‐ (1) 4‐ (2) or 2,6‐ (3) were prepared from the aminolysis of chlorodiphenylphosphine with 2‐isopropylaniline, 4‐isopropylaniline or 2,6‐diisopropylaniline, respectively, under anaerobic conditions. Oxidation of 1,2 and 3 with aqueous hydrogen peroxide, elemental sulfur or gray selenium gave the corresponding oxides, sulfides and selenides (Ph₂P?E)NH? C₆H₄? 2‐CH(CH₃)₂, (Ph₂P?E)NH? C₆H₄? 4‐CH(CH₃)₂ and (Ph₂P?E)NH? C₆H₄? 2,6‐{CH(CH₃)₂}₂, where E = O, S, or Se, respectively. The reaction of [M(cod)Cl₂] (M = Pd, Pt; cod = 1,5‐cyclooctadiene) with two equivalents of 1,2 or 3 yields the corresponding monodendate complexes [M((Ph₂P)NH? C₆H₄? 2‐CH(CH₃)₂)₂Cl₂], M = Pd 1d, M = Pt 1e, [M((Ph₂P)NH? C₆H₄? 4‐CH(CH₃)₂)₂Cl₂], M = Pd 2d, M = Pt 2e and [M((Ph₂P)NH? C₆H₄? 2,6‐(CH(CH₃)₂)₂)₂Cl₂], M = Pd 3d, M = Pt 3e, respectively. All the compounds were isolated as analytically pure substances and characterized by NMR, IR spectroscopy and elemental analysis. Furthermore, representative solid‐state structure of [(Ph₂P?S)NH? C₆H₄? 4‐CH(CH₃)₂] (2b) was determined using single crystal X‐ray diffraction technique. The complexes 1d–3d were tested and found to be highly active catalysts in the Suzuki coupling and Heck reaction, affording biphenyls and stilbenes, respectively. Copyright © 2009 John Wiley & Sons, Ltd.     

Gold nanoparticle included graphene oxide modified electrode: Picomole detection of metal ions in seawater by stripping voltammetry

We obtained a gold nanomaterial/graphene oxide-modified glassy carbon electrode and characterized it using transmission electron microscope, scanning electron microscope, cyclic voltammetry (CV), and X-ray photoelectron spectroscopy techniques. A response of the electrode using square wave anodic stripping voltammetry for Pb²⁺, Cu²⁺, and Hg²⁺ was found linear in the range from 1 × 10^–7 to 1 × 10^–11 M. The detection limits of Pb²⁺, Cu²⁺ and Hg²⁺ were 0.14, 0.5 and 1.2 pM, respectively. The method was applied to the simultaneous determination of Pb²⁺, Cu²⁺ and Hg²⁺ in seawater samples from a coastal region of Anatolia, and the results corresponded well with the values obtained by inductively coupled plasma-optical emission spectroscopy.     

Numerical investigation of the solution of Fisher's equation via the B‐spline Galerkin method

The Galerkin method is used with quadratic B‐spline base functions to obtain the numerical solutions of Fisher's equation which is a one dimensional reaction‐diffusion equation. To observe the effects of reaction and diffusion, four test problems related to pulse disturbance, step disturbance, super‐speed wave and strong reaction are studied. A comparison is performed between the obtained numerical results and some earlier studies. © 2009 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2010     

The Novel N,S-Substituted Halonitrodienes from the Reactions of Thiosubstituted Nitrodiene with Piperazine and Morpholine

The substituted 1,2-dibromomethanethio nitrodiene 2 was obtained from the addition of bromine to S-substituted nitrodien 1 in carbon tetrachloride. N, S-substituted compounds 4a–h were synthesized from the reactions of compound 2 with several substituted piperazine derivatives 3a–h in dichloromethane. N, S-substituted compounds 6 and 8 were synthesized from the reaction of 2 with morpholine ( 5 ) and thiomorpholine ( 7 ) in dichloromethane, respectively. Dibutadienyl piperazines 10 , 12 , and 14 were synthesized from the reactions of 2 with homopiperazine ( 9 ), piperazine ( 11 ), and 2,5-dimethylpiperazine ( 13 ), respectively.