Removal of copper from industrial wastewater by cementation on zinc in baffled batch-agitated vessels

Rates of Cu++ removal from waste solution by cementation on zinc in a baffled-agitated vessel lined with a cylindrical zinc sheet were studied under different conditions of impeller rotation speed, initial copper concentration, temperature and time of cementation. It was found that the rate of Cu++ removal increases with increasing impeller rotation speed, initial concentration, temperature and residence time at pH = 4. The cementation rate temperature dependence was found to be of Arrhenius type with an activation energy of 23 J/mol confirming the diffusion controlled nature of the reaction. Mass transfer study of the process has revealed that the data for the conditions: 57628 < Re < 485550 and 638 < Sc < 1697 fit the following dimensionless equation: Sh = 0.035Re0.89 Sc 0.3

Serological Survey on Toxoplasma gondii in some Dairy Animals and Pregnant Women in Qena, Egypt

Toxoplasmosis is an important reason of reproductive failure in human and farm animals causing significant socioeconomic losses worldwide. Additionally, infection in pregnant women can cause severe health problems in the child as mental retardation and blindness. In this work the seroprevalence of T. gondii infection was estimated in dairy goats, sheep, and cows as well as in pregnant women in Qena Province, Egypt using the Enzyme Linked Immunosorbent Assay (ELISA). The study included 150 raw milk samples which were collected from the previously mentioned animals in different localities (50 from each) as well as 100 pregnant women serum samples with a history of abortion. Our results revealed that T. gondii IgM and both IgM &amp; IgG antibodies were detected in 20, 40 and 28, 6% of goat and sheep milk samples, respectively. While T. gondii IgM antibodies could be detected in 64% of cow milk samples. A total of 28 (28%) women were seropositive for toxoplasmosis, divided into 2 (2%) were seropositive for T. gondii IgM antibodies and 26 (26%) for IgG. There was an association between IgG seroprevalence and age and the times of abortion in pregnant women

Epstein-Barr virus: clinical and epidemiological revisits and genetic basis of oncogenesis

Epstein-Barr virus (EBV) is classified as a member in the order herpesvirales, family herpesviridae, subfamily gammaherpesvirinae and the genus lymphocytovirus. The virus is an exclusively human pathogen and thus also termed as human herpesvirus 4 (HHV4). It was the first oncogenic virus recognized and has been incriminated in the causation of tumors of both lymphatic and epithelial nature. It was reported in some previous studies that 95% of the population worldwide are serologically positive to the virus. Clinically, EBV primary infection is almost silent, persisting as a life-long asymptomatic latent infection in B cells although it may be responsible for a transient clinical syndrome called infectious mononucleosis. Following reactivation of the virus from latency due to immunocompromised status, EBV was found to be associated with several tumors. EBV linked to oncogenesis as detected in lymphoid tumors such as Burkitt's lymphoma (BL), Hodgkin's disease (HD), post-transplant lymphoproliferative disorders (PTLD) and T-cell lymphomas (e.g. Peripheral T-cell lymphomas; PTCL and Anaplastic large cell lymphomas; ALCL). It is also linked to epithelial tumors such as nasopharyngeal carcinoma (NPC), gastric carcinomas and oral hairy leukoplakia (OHL). In vitro, EBV many studies have demonstrated its ability to transform B cells into lymphoblastoid cell lines (LCLs). Despite these malignancies showing different clinical and epidemiological patterns when studied, genetic studies have suggested that these EBV- associated transformations were characterized generally by low level of virus gene expression with only the latent virus proteins (LVPs) upregulated in both tumors and LCLs. In this review, we summarize some clinical and epidemiological features of EBV- associated tumors. We also discuss how EBV latent genes may lead to oncogenesis in the different clinical malignancie

E-IASAODV: an enhanced framework for preventing Ad-hoc on-demand Distance Vector (AODV) multiple black hole attack in MANET

Mobile Ad-hoc networks (MANETS) are collection of mobile nodes that dynamically change the network topology in which nodes can join and leave the network at any point of time. Due to fundamental characteristics of MANETS, such as open medium, dynamic topology, and distributed cooperation; it creates several security vulnerabilities to its security design. Security is an essential requirement in mobile Ad-hoc networks to provide secure communication between mobile nodes. Ad-Hoc On-demand Distance Vector (AODV) routing protocol is a routing protocol in MANET that broadcast the network with a route discovery message anytime a node is seeking for a route to a destination, any node that have a route to that destination will reply to the route discovery request, which provides a vulnerability to the routing protocol by making it open to black hole attack which is one of the most common attacks in MANETs. A Black Hole is a malicious node that falsely replies to any route requests without having active route to specified destination and drops all received packets. This work, which is an enhancement of Intrusion Avoidance System for Ad-Hoc on-demand Distance Vector (IASAODV), a framework developed in 2015 to prevent black hole attack, presents a new framework that prevents the security threats of AODV multiple Black Hole attack with better Packet Delivery Ratio (PDR). This framework tackled the problem by making nodes monitor the activities of their neighbors by collecting Route Request (RREQ) messages sent by nodes and keeping in a table. To justify the solution, we made appropriate implementation and simulation using Network Simulator NS-2.35. The conducted experimental result shows an improvement in Packet Delivery Ratio (PDR) compared to that of IASAODV routing Protocol with the proposed framework having 100%, 100%, 99% and 98% for 1, 3, 5 and 7 malicious nodes respectively compared to the existing system with 88%, 79%, 61% and 57%, for 1,3,5 and 7 malicious nodes respectivelyKeywords: MANETs, AODV, IASAODV, RREQ, RREP, NS2, HRR

Photocatalytic decolorization of methylene blue using TiO2/UV system enhanced by air sparging

In this work, the photocatalytic degradation of wastewater containing an organic dye (Methylene Blue) was investigated in a slurry-type reactor enhanced by air sparging. Commercial TiO2 was used as the photocatalyst which was activated using ultraviolet irradiation. The effects of initial dye concentration, photocatalyst loading, solution pH and air’s superficial velocity on the degradation efficiency were evaluated. The degradation efficiency of the dye increased with increasing the pH of the solution and decreasing the initial dye concentration. Moreover, increasing the catalyst loading up to 1 g/l showed an improvement in the degradation efficiency. However, the efficiency deteriorated with a further increase in the catalyst loading. Introducing air into the reaction medium in the form of micro-bubbles significantly improved the degradation efficiency by providing oxygen molecules required for the oxidation reaction. Furthermore, these air bubbles created turbulence in the reaction medium, which resulted in the enhancement of the mass transfer rate of dye molecules from the solution bulk to the catalyst surface with a subsequent increase in the degradation efficiency. A complete decolorization of 10 ppm dye solution was achieved in the neutral solution (pH = 7) with a catalyst loading of 1 g/l and an air superficial velocity around 2 cm/s. The effect of the air superficial velocity on the degradation reaction kinetics was investigated and the reaction was found to follow the pseudo second order rate law. Keywords: Photocatalysis, TiO2, Air sparging, Methylene blue, Ultraviole

Improving the rate of Cu+2 recovery from industrial wastewater using a vertical array of reciprocating perforated zinc discs

AbstractThis work investigates the possibility of improving the rate of Cu+2 recovery and/or removal from industrial wastewater by cementation technique using an array of pulsating horizontal perforated zinc discs. The results show that the rate of cementation was found to increase by increasing frequency and amplitude of oscillation (vibrating velocity); disc diameter; copper ion concentration and solution temperature while decreasing by increasing the disc separation. Under certain conditions using pulsating array of perforated zinc discs was found to increase the rate of mass transfer by a factor of 17 times the stagnant discs. The activation energy of the reaction was found to be 8.948kcal/mol which indicates that under the present conditions cementation takes place under mixed control, i.e. the reaction is partially diffusion control. As such no overall mass transfer correlation could be obtained

Designing an Inclusive City with Chrono-Urbanism Principles

A study was conducted in Tallasa District, the newly developing district in Makassar, Indonesia, to examine all public facilities accessible in the Chrono-Urbanism timeframe and promote social inclusion and equal participation. The study found that while the concept may not be sustainable in the long term, potential development could be achieved through adjustments in spatial planning connections and involving a wide range of age groups in neighborhood designs. The study used the principles of proximity, diversity, density, and digitalization to analyze the concept. The results showed that only the diversity criteria almost met the accessibility and inclusiveness aspects. Applying the Chrono-Urbanism theory may encounter difficulties in regions with large populations and distinctive geographical features such as Indonesia's archipelago. Diverse demographic characteristics, various transportation needs between different areas, and differences in economic and educational strata pose specific challenges. The complexities in managing urban spaces and ensuring proximity and accessibility become more pronounced in densely populated areas and require considerations to accommodate the unique circumstances of each region like Tallasa District in Makassar

Effect of dye extracting solvents and sensitization time on photovoltaic performance of natural dye sensitized solar cells

In this study, natural dye sensitizer based solar cells were successfully fabricated and photovoltaic performance was measured. Sensitizer (turmeric) sources, dye extraction process, and photoanode sensitization time of the fabricated cells were analyzed and optimized. Dry turmeric, verdant turmeric, and powder turmeric were used as dye sources. Five distinct types of solvents were used for extraction of natural dye from turmeric. Dyes were characterized by UV–Vis spectrophotometric analysis. The extracted turmeric dye was used as a sensitizer in the dye sensitized solar cell’s (DSSC) photoanode assembly. Nano-crystalline TiO2 was used as a film coating semiconductor material of the photoanode. TiO2 films on ITO glass substrate were prepared by simple doctor blade technique. The influence of the different parameters VOC, JSC, power density, FF, and η% on the photovoltaic characteristics of DSSCs was analyzed. The best energy conversion performance was obtained for 2 h adsorption time of dye on TiO2 nano-porous surface with ethanol extracted dye from dry turmeric. Keywords: DSSC, Natural dye, TiO2 photoanode, Dye extracting solvent, Dye-adsorption tim