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Switched-boost inverter (SBI) is a single-stage power converter suitable for interfacing between photovoltaic (PV) arrays and loads. Although, it has many advantages such as it's not requiring an expensive complex dead-time circuitry, yet its duty ratio is limited between 0 and 0.5. This means that it has some difficulties in increasing both the DC-link output voltage and its AC-output voltage. So, most researchers proposed it for low-voltage power applications or using with step-up transformers. Accordingly, this study contributes towards improving the performance of the SBI for being used in the modified nanogrid within an open energy system. It introduces a novel approach closed-loop control technique to overcome most of the inverter drawbacks. Also, it enhances both the DC-link and the transformer-less rated AC output voltages to a sufficient value suitable for feeding domestic loads. And in the same time, the proposed robust controller utilizes a hysteresis band for balancing between voltage stability and PV-maximum power achievement. This research also includes a more sophisticated fast-charging slow-discharging control strategy for the battery energy management system that depends on a bidirectional buck-boost converter. Test results ensure the robustness of the proposed controller against sensitivity, nonlinearity, and time-variant parameters of the overall system.

Effects of complaint wall properties on the flow of a Newtonian viscous compressible fluid has been studied when the wave propagating (surface acoustic wave, SAW) along the walls in a confined parallel-plane microchannel is conducted by considering the slip velocity. A perturbation technique has been employed to analyze the problem where the amplitude ratio (wave amplitude/half width of channel) is chosen as a parameter. In the second order approximation, the net axial velocity is calculated for various values of the fluid parameters and wall parameters. The phenomenon of the “mean flow reversal” is found to exist both at the center and at the boundaries of the channel. The effect of damping force, wall tension, and compressibility parameter on the mean axial velocity and reversal flow has been investigated, also the critical values of the tension are calculated for the pertinent flow parameters. © 2009 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 27: 621–636, 2011 Keywords

Gamma irradiation effects on larvae of the housefly Musca domestica were studied. Larvae (1, 2, 3, 4, 5 and 6 days old) exposed to gamma rays showed that younger larvae were more susceptible than older one. Pupation was observed at all dosages and its percentage was higher in the case of old larvae than that in younger one. At 400 rad and 1400 rad pupation percent was 74% and 46% in the case of one day old larvae respectively. In the case of 6 days old larvae this percent was 100% and 92% at the same doses respectively. From all aged larvae, emergence of adult flies was observed and its percentage decreased with the increase of dose level of irradiation. At 400 rad and 1200 rad in the case of one day old larvae, percent of emergence was 74% and zero respectively, while in the case of 6 days old larvae these percentages were 78.94% and zero at the same dose levels respectively. Generally, flies emerged from irradiated larvae died earlier than the control flies. Zusammenfassung Wirkungen von Gammastrahlen auf die Larven und Adulten der Hausfliege Musca domestica L. Bei Behandlung von 1, 2, 3, 4, 5 und 6 Tage alten Hausfliegenlarven mit Gammastrahlen zeigten die jungeren Larven grosere Empfindlichkeit als die alteren. Zur Verpuppung gelangte ein verschieden groser Anteil der Larven bei allen Dosierungen. Dabei nahm das Verpuppungsprozent mit dem Alter der bestrahlten Larven zu. Bei 400 und 1400 rad betrug die Verpuppungsquote 47 und 46%, wenn 1 Tag alte Larven bestrahlt wurden. Im Falle von 6 Tage alten Larven betrugen die Quoten 100 und 92%. Die Schlupfquote der Fliegen nahm, mit steigender Strahlendosis appliziert, bei den Larven ab. Wurden 1 Tag alte Larven mit 400 und 1200 rad bestrahlt, betrug die Schlupfquote der Fliegen 74% und Null, wahrend sie nach Behandlung 6 Tage alter Larven nur wenig hoher war (78,94% und Null). Im allgemeinen starben Fliegen, die aus bestrahlten Larven hervorgingen, eher ab als unbehandelte.

A series of castor oil adducts were synthesized by esterification of castor oil with acid anhydrides: phthalic, maleic and succinic anhydrides. The chemical structure of castor oil and the prepared adducts were characterized by means of IR and 1 H NMR spectroscopy. The number-average and weight-average molecular weights were measured by gel permeation chromatography. The electrical properties were studied through the permittivity, dielectric loss and conductivity measurements, which are considered to be in the range of electrical insulation. The electrical conductivity, which describes the ionic mobility of the systems, was found to be in the range of 10 -9 to 10 -12 S/cm. This indicates that castor oil and its esters could be used for antistatic applications. The viscosity η and the activation energy E n , obtained from the dependency of viscosity on temperature using the Arrhenius equation, were found to increase with increasing molecular weight of the system. The effect of different concentrations of castor oil and its esters on the growth activities of the sugar beet pathogens R. solani and S. rolfsii was studied through the determination of percent germination, average length of hyphal extensions, dry mass yield and the production of sclerotia. The obtained data indicate that the esterification of castor oil with anhydrides improves the antifungal activity.

The network structure, mechanical properties, and thermal gravimetric of epoxy resin filled with plasticized carbon black (CB) have been studied. The effect of CB concentration on composite morphology as well as cross linking density (n), volume fraction of resin (Vr), degree of crystallinity (Xc), mean gap among conductive particles (g), aspect ratio (F), and mechanical property such as modulus of elasticity (Ym), hardness (HA), and elongation at break (EB) have been examined and correlated to establish structure–property relationships. According to the thermal gravimetric analysis, the thermal decomposition of the composite took place at a slightly higher temperature than that of green epoxy. It proved that the inclusion of plasticized CB improves the quality of the network structure and enhances the mechanical properties of the composites. POLYM. COMPOS., 2008. © 2008 Society of Plastics Engineers.

The development of conductive polymer composites remains an important endeavor in light of growing energy concerns. A conducting polymer composite in the presence of plasticized carbon black (CB) and epoxy resin has been developed. Room temperature electrical conductivity, mobility carriers (μ), and number of charges (N) increase by increasing CB content. Electrical conductivity–temperature dependence of the composite was investigated and negative temperature coefficient of conductivity (NTC) behavior of the composites was revealed. The mechanism of the NTC effect in materials is related to the thermal expansion of the epoxy matrix and barriers height energy. The current–voltage behavior of epoxy/CB composites shows a switching effect and the mechanism of negative resistance is interpreted in details. Thermal conductivity (γ) increases with increasing filler content and the experimental data was compared with a theoretical model based on energy balance equation. POLYM. COMPOS., 2008. © 2008 Society of Plastics Engineers

The Lossen rearrangement of aromatic hydroxamic acids under Heck conditions affords the corresponding aryl amines while aliphatic and hetaryl hydroxamic acids yield symmetric ureas.

Nitric oxide (NO) and vasoactive intestinal polypeptide (VIP) interact in the regulation of neuromuscular function in the gut. They are also potent intestinal secretogogues that coexist in the enteric nervous system. The aims of this study were: (1) to investigate the interaction between NO and VIP in inducing fluid secretion in the rat jejunum, and (2) to determine whether the NO effect on intestinal fluid movement is neurally mediated. The single pass perfusion technique was used to study fluid movement in a 25 cm segment of rat jejunum in vivo. A solution containing 20 mml-arginine, a NO precursor, was perfused into the segment. The effect of the NO synthase inhibitors (l-NAME and l-nitroindazole (l-NI)) and the VIP antagonist ([4Cl-D-Phe6,Leu17]VIP (VIPa)) on l-arginine-induced changes in fluid movement, expressed as μl min−1 (g dry intestinal weight)−1, was determined. In addition, the effect of neuronal blockade by tetrodotoxin (TTX) and ablation of the myenteric plexus by benzalkonium chloride (BAC) was studied. In parallel groups of rats, the effect of l-NAME and l-NI on VIP-induced intestinal fluid secretion was also examined. Basal fluid absorption in control rats was (median (interquartile range)) 65 (45–78). l-Arginine induced a significant fluid secretion (−14 (−20 to −5); P < 0.01). This effect was reversed completely by l-NAME (60 (36–65); P < 0.01) and l-NI (46 (39–75); P < 0.01) and partially by VIPa (37 (14–47); P < 0.01). TTX and BAC partially inhibited the effect of l-arginine (22 (15–32) and 15 (10–26), respectively; P < 0.05). The effect of VIP on fluid movement (−23 (−26 to −14)) was partially reversed by l-NAME (24 (8.4–35.5); P < 0.01) and l-NI (29 (4–44); P < 0.01). The inhibition of VIP or NO synthase prevented l-arginine- and VIP-induced intestinal fluid secretion through a neural mechanism. The data suggest that NO enhances the release of VIP from nerve terminals and vice versa. Subsequently, each potentiates the other's effect in inducing intestinal fluid secretion.

Two procedures for the prepation of dimethylsilyl bis-enol ethers from aldehydes, through enolization, are described. Dimethylsilyl bis-enol ethers, derived from propanal, butanal, 2-methylpropanal...

Several new hydrazidoyl halides containing the 2-thiazolin-4-one moiety were synthesised and reacted with several reagents to yield several additional heterocyclics. Structures were based on both elemental analysis and spectral data.

The synthesis of several rigid analogs of catecholamine type of adrenergic agents is reported. Their synthesis began with a Diels-Alder cycloaddition of 4,5-dibenzyloxybenzyne (generated from 4,5-dibenzyloxyan-thranilic acid) to 1-(2-trans-phenylvinyl)-2-pyridone and 1-benzyl-3-benzyloxy-2-pyridone. The unsaturated amides so produced were reduced first with hydrogen and palladium and then with lithium aluminum hydride to provide 6,7-dihydroxy-1,4-ethano-1,2,3,4-tetrahydroisoquinolines. Homonuclear and heteronuclear two-dimensional chemical shift correlation nmr spectroscopy confirmed the structure of the bridged tetra-hydroisoquinolines and led to the unambiguous assignment of the 1H and 13C nmr chemical shifts of key compounds.

In the present study, the electrical conductivity (σ) of ball-milled and NaOH treated cotton fibres were measured in vacuum. The induced electrical conductivity and the activation energy ΔE of γ-irradiated samples were measured as a function of radiation doses and at various temperatures. It was found that γ-irradiation of cotton fibres either decreases or increases its electrical conductivity. Thus, it was found that γ-irradiations of cotton reduces the conductivity of the samples having particles sizes ranging from 0.07 to 0.11 mm and the magnitude of the reduction deminuishes as the particle size increases. The results have also showed that for any given concentration γ-irradiation of NaOH treated samples causes an increase of the measured electrical conductivity.

The electrical conductivity, thermoelectric power and thermal conductivity of CuTlTe2 in the solid and liquid states were measured over a wide range of temperature. The experimental data were analyzed in terms of a model developed for the density of states and electrical transport in solid amorphous semiconductors. Positive thermoelectric power suggests a large predominance of holes in electrical transport.

When the diazonium salt (I) is heated in dichloroethane in the presence of propylene oxide, the tetra(benzyloxy)azobenzene (II) is obtained in the form of orange crystals.