Efecto de la radiación UV-C y del agua caliente en el contenido de calcio y calidad poscosecha de manzanas

To increase the storage shelf life of "Red Delicious" and "Golden Delicious" apples they were treated with UV-C irradiation at doses of 0, 5 and 15 min irradiation at 1.435 x 10E-4 W/square cm and with hot water containing 4% CaCl2 at four levels (control, dipping at 25 deg C for 10 min, dipping at 38 deg C for 5 min and dipping in 54 deg C for 1 min) in a factorial design with 4 replicates. The results showed that UV-C irradiation and dipping of fruit in hot water increased the storage life and improved fruit quality factors in "Red Delicious" and "Golden Delicious" apples at the end of cold storage. Both UV-C and hot water treatments decreased pH and total soluble solids/titratable acids ratio and increased fruit titratable acids and firmness. UV-C and hot water treatment increased fruit Ca content during storage. The results showed that UV-C and hot water treatment can retard fruit ripening and maintain fruit quality in cold storage. These treatments can also increase Ca concentration of fruit flesh and thus increase the nutritional value of the apples.Con el fin de prolongar el periodo de vida útil durante la conservación frigorífica de manzanas "Red Delicious" y "Golden Delicious", éstas se trataron con radiación UV-C en tres dosis (0, 5 y 15 min de irradiación a 1,435 x 10E-4 W/cm cuadrado) y agua caliente con CaCl2 al 4% en cuatro niveles (control 0, inmersión a 25 grados C 10 min, 38 grados C 5 min ó 54 grados C 1 min), en un diseño factorial con 4 repeticiones por tratamiento. La irradiación con UV-C y la inmersión de los frutos en agua caliente permitió alargar el periodo de conservación y mejoró la calidad de manzanas "Red Delicious" y "Golden Delicious" tras el almacenamiento en frío. Ambos tratamientos aumentaron la acidez titulable y la firmeza de los frutos, también disminuyeron el pH y la relación sólidos solubles/acidez. El tratamiento con UV-C y agua caliente incrementó el contenido en calcio de los frutos durante el almacenamiento. Los resultados muestran que estos tratamientos pueden retrasar los procesos de maduración de los frutos y mantener su calidad durante el almacenamiento frigorífico, así como aumentar el contenido en Ca de la pulpa del fruto y por tanto incrementar su valor nutricional

Reuse of Iraqi Agricultural Drainage Water Using Nanofiltration

Abstract: Irrigated areas between Euphrates and Tigris rivers in Iraq suffer from salinity buildup in the root zone of corps. Agricultural drain water (ADW) from these areas is collected in a single main drain canal, in an annual flow rate of about 6 billion cubic meter. In the present work, a pilot-scale nanofiltration membranes unit was used to evaluate the feasibility of desalinating ADW from the main drain canal for further reuse. Bench scale experiments were conducted to determine the optimum anti-scale dosage values in the unit. These values were verified in a plate type laboratory scale NF membrane to visually monitor the onset of crystal appearance behavior. A method for calcium sulfate precipitation control is presented and an empirical correlation of anti-scale dosage as a function of concentration factor (CF) was obtained. A pilot-scale unit was used to investigate the performance of NF membrane. High rejection values for both cations and anions indicate that the use of NF membrane in desalinating ADW from the Iraqi main drain canal is promising. The treated drainage water is considered good for irrigation when classified according to Wilcox classification

Histological characterisation of the skin of the Paraechinus hypomelas, Brandt, 1836 (Erinaceidae: Eulipotyphla)

Background: The current study represents the first description of the histological characterisations of the normal skin of Brandt’s hedgehog (paraechinus hypomelas). Materials and methods: Skin samples were collected from abdomen, back, nostril and cloacal regions. Results: The skin consisted of 3 layers including epidermis, dermis and hypodermis. The epidermis was covered by a layer of keratinised squamous epithelium mainly in the back region, but the skin keratinisation was present with a little amount or may was absent in other regions. Histologically, the total thickness of skin was maximum on the back and minimum on the cloacal regions. The epidermis consisted of 4 layers and stratum lucidum was absent in all regions. Beneath the epidermis, the dermis layer was constituted of dense connective tissue in which the hair follicles, sweat glands, sebaceous glands, arrector pilli muscles and blood vessels were present. The sweat and sebaceous glands were more populated in the nostril region. The hair follicles were located in the epidermal and dermal regions. Vibrissae were only in the nostrils region and characterised from other hairs by their large and well innervated hair follicle which was surrounded by the blood sinus. Conclusions: The present findings show that in Brandt’s hedgehog (paraechinus hypomelas) the back and cloacal regions have thickest and thinnest skin respectively as compared to the nostril and abdominal regions. In addition, sebaceous and sweat glands were mainly populated in the nostril regio

Dual-band dual linear to circular polarization converter in transmission mode-application to K/Ka-band satellite communications

Many wireless communication applications such as satellite communications use circularly polarized (CP) signals, with the requirement for easy switching of the polarization sense between uplink and downlink. Specifically, in satellite communications, the trend is also to move to higher frequencies and integrate the receiving and transmitting antennas in one dual-band terminal. However, these simultaneous demands make the design and fabrication of the composing parts very challenging. We propose, here, a dual-band dual-linear polarization (LP)-to-CP converter that works in the transmission mode. The working principle of this polarizer is explained through an example for Ka-band satellite communications at 19.7–20.2 and 29.5–30 GHz. The LP-to-CP converter is a single panel composed of identical unit cells with a thickness of only 1.05 mm and a size of 5.3 mm ×5.3 mm. Due to its operation in the transmission mode, the polarizer can be combined with a simple dual-band dual-LP antenna to obtain the desired dual-band dual-CP single antenna. However, the unique property of this polarizer is yet the fact that it converts a given LP wave, e.g., x-polarization, to orthogonal CP waves at the two nonadjacent frequency bands, e.g., left-handed CP at lower band and right-handed CP at higher band. The polarizer is tested both with 20 and 30 GHz LP rectangular horns to illuminate a dual-band transmit array (TA) to obtain wide-angle steering of CP beams. The performance of the polarizer and its association with the TA is evaluated through simulation and measurements. We also present design guidelines for this type of polarizer.info:eu-repo/semantics/acceptedVersio

Computer Modeling of a Glass Stream Departing from a Pour Spout Knife Edge

The subject of this paper is the hydrodynamics of pouring molten glass. This involves a class of free surface flows that changes shape from flat film flow on a wall to a round cylindrical jet in the free fall region, which as not previously received much attention

Ag-Functionalized CuWO₄/WO₃ nanocomposites for solar water splitting

Ag-Functionalized CuWO 4 /WO 3 heterostructures were successfully prepared via a polyvinyl pyrrolidone (PVP)-assisted sol-gel (PSG) route. Thin films prepared via electrophoretic deposition were used as photoanodes for photoelectrochemical (PEC) water splitting. Compared to pristine CuWO 4 and WO 3 films, a significant enhancement of the photocurrent (3-4 times) at the thermodynamic potential for oxygen evolution (0.62 V vs. Ag/AgCl, pH 7) was obtained for the Ag-functionalized CuWO 4 /WO 3 photoanodes. The obtained enhancement is shown to be derived from a synergic contribution of heterostructure formation (CuWO 4 /WO 3 ) and improvements of light utilization by Ag-induced surface plasmon resonance (SPR) effects. Accordingly, a photocurrent of 0.205 mA cm -2 at 0.62 V vs. Ag/AgCl under neutral conditions (without hole scavengers) under front-side simulated AM1.5G illumination was achieved. A detailed analysis of the obtained PEC data alongside performed impedance measurements suggests that charge seperation is significantly improved for the prepared Ag-functionalized CuWO 4 /WO 3 photoanodes. Our work offers beneficial insights to design new plasmonic metal/heterostructured nanocomposites for energy conversion applications

Full-wave evaluation of a 40 dBi: Transmit-array for Ka-band SoTM

Transmit-array (TA) antennas have been shown to be a cost-effective solution for the new generation of satellite communications. These antennas are usually composed by thousands of fine-tuned subwavelength unit-cells. Therefore, full-wave evaluations become quite challenging as the required gain increases, constraining the antenna design and optimization. This is aggravated by the fact that, when beam scanning is required, higher gains cannot be obtained by simply scaling a given design. In fact, for a F/D ratio, the maximum gain of the TA is limited by the scanning aberrations. Recently, we have proposed a new phase compensation law for the TA, designated as the bifocal correction, that allows to overcome the usual gain/scanning tradeoff limit. However, due to the lack of computational resources, we were only able to demonstrate this concept for a 40 dBi TA using PO/GO methods. In this communication we present the full-wave performance of this 40 dBi bifocal TA design using a new efficient numerical evaluation method, properly validated with a smaller 30 dBi TA.info:eu-repo/semantics/acceptedVersio

Equivalent dielectric description of transmit-arrays as an efficient and accurate method of analysis

Transmit-arrays (TAs) provide cost-effective solutions for various antenna applications, including satellite and terrestrial communications. Usually, these antennas have electrically large apertures, comprising thousands of fine-tuned subwavelength unit-cells. This makes full-wave simulations demanding in terms of computational resources, constraining the antenna design and optimization. Herein, we present an efficient method for the reduction of the TA's computational complexity that still provides accurate results for the main figures of merit of the antenna. For the chosen example, the simulation was 3 times faster and required 50% less memory. Yet, as the complexity of the problem is further scaled, this method is expected to become even more effective.info:eu-repo/semantics/acceptedVersio

Wide-angle mechanical scanning Transmit-arrays for satellite Ka-band user terminals

The antenna design for broadband satellite communications is particularly challenging, new cost-effective solutions are still needed. An overview of recent contributions from the authors on planar transmit-arrays (TAs) for satellite Kaband user terminals is presented. We tackle several design problems: how to improve the scanning coverage using low cost mechanical beam steering, how to choose the type of unit cells that compose the TA, how to devise a single aperture with high gain that operates simultaneous at two widely separate frequency bands. Different prototypes are used to conduct these studies. All these TAs provide wide beam zenith scanning, [-50º,50º] with less that 3dB of scan loss, good circular polarization performance and low beam distortions. The prototypes have the same aperture size, 195 × 145 mm2, that provide gains up to 29 dBi for 30 GHz.info:eu-repo/semantics/acceptedVersio

The effect of seeds of different chickpea and cowpea cultivars on digestive proteolytic activity of Helicoverpa armigera (Lep.: Noctuidae)

Proteases are considered as major digestive enzymes in alimentary canals of most insects, which are responsible for providing amino acids and energy from nutrients for insectsâ growth. The substrate azocasein was used for measuring general proteolytic activity of midgut extracts from Helicoverpa armigera (Hübner) larvae reared on different chickpea cultivars (Arman, Azad, Binivich and Hashem) and a cowpea cultivar (Mashhad) when incorporated into artificial diets at different pH values (6 to 12). The experiments were preformed at 25 ± 1Cº, 65 ± 5% RH and a photoperiod of 16: 8 (L: D) h. The results showed that the lowest general proteolytic activity of the third, fourth and fifth instar larvae was on Arman, Binivich and Arman (4.31, 4.26 and 4.31 U/mg, respectively), while the highest rate was in the larvae fed on Mashhad, Azad and Mashhad (6.68, 6.31 and 6.67 U/mg, respectively), respectively. The general proteolytic activity in H. armigera larvae on all examined cultivars had an increasing trend in pH from 6 to 12. The optimum pH value of proteolytic activity in the larvae fed on different cultivars was 12, suggesting the maximum proteolytic activity of H. armigera larvae at high alkaline pH. Mashhad and Arman cultivars were the most and the least suitable hosts for H. armigera, respectively