Gamma Photon Column Scanning of Prototype and Industrial Distillation Columns

Monte Carlo simulation of gamma photon transport and interaction with the distillation column and its contents was performed in order to predict the effects of gamma photons when they interact with matter. The results of the interaction and transport of gamma photons are presented as energy deposition on the distillation column and its contents. Energy attenuation was more pronounced on the column walls and trays as compared to the region between the trays, where there is mostly vapour space. Gamma column scanning was then used to verify the Monte Carlo simulation results by scanning and investigating the integrity of two laboratory prototype distillation and industrial distillation columns. One of the prototype distillation columns was 1 m tall with four trays and the other one was 1.8 m tall consisting of six trays and a packed bed. Commonly encountered distillation column malfunctions such as collapsed tray, weeping, flooding and foaming were simulated in the two prototype distillation columns and scanned. The industrial distillation column was a 26 m tall benzole prefractionator column, consisting of 60 single pass trays and a diameter of 0.8 m. A 10 mCi 60Co gamma radiation source and NaI(Tl) scintillation detector were used to scan the distillation columns. The results from the two prototypes showed that all the simulated malfunctions were clearly detected except for foaming. The results from industrial distillation column showed that all the trays were in their correct position although tray number 32 could be partially damaged and just below tray 41, the scan revealed that there was a loss of column wall thickness. The obtained density profile for the industrial distillation column showed some small variations from the expected density profile and this was attributed to external features on the distillation column and wind bursts that shifted the source and detector from the chosen scan line orientation.

Molecular study of HCV detection,genotypes and their routes of transmission in North West Frontier Province,Pakistan

Objective:To determine hepatitis C virus(HCV) genotypes and explore the associated risk factors in chronic HCY patients.Methods:A total of 116 patients with chronic hepatitis C were subjected to polymerase chain reaction(PCR) based detection out of which 112 chronic HCV patients[53 male(47.32%),59 female(52.68%);mean age(43.76±16.40) years;mean BMI(23.8± 3.9)kg]were enrolled in this study.The frequency of 6 HCV genotypes and associated risk factors were evaluated from five districts of North West Frontier Province(NWFP).Results:Genotype 3was the most prevalent in 73 samples(65.17%) followed by genotype 1 in 24(21.42%) and genotype2 in 13(11.60%) samples.Genotype3 had significantly high prevalence(P=0.0002).The results showed that 48(42.85%) samples were infected with HCV 3a:25(22.32%) with 3b;14(12.50%) with 1a;10(8.92%)with 1b;11(9.82%) with 2a;2(1.78%) with 2b;and 2 were untypable.The distribution of HCV genotypes in Murdan.Charsadda,Peshawar.Sawabi and Nowshehra districts was different.Use of unsterile equipment lor medication,barbers and previous history of hospitalization were the main risk factors for HCV transmission.Conclusions:Cenotype 3a and 3b.1a.1b and 2a are the common genotypes in NWFP.Genotype 4.5.and 6 can not be found in a single sample.The level of awareness about various modes ot transmission of HCV among the population is found to be verv low.

Numerical Analysis for the Effect of Irresponsible Immigrants on HIV/AIDS Dynamics

The human immunodeficiency viruses are two species of Lentivirus that infect humans.Over time,they cause acquired immunodeficiency syndrome,a condition in which progressive immune system failure allows life-threatening opportunistic infections and cancers to thrive.Human immunodeficiency virus infection came from a type of chimpanzee in Central Africa.Studies show that immunodeficiency viruses may have jumped from chimpanzees to humans as far back as the late 1800s.Over decades,human immunodeficiency viruses slowly spread across Africa and later into other parts of the world.The Susceptible-Infected-Recovered(SIR)models are significant in studying disease dynamics.In this paper,we have studied the effect of irresponsible immigrants on HIV/AIDS dynamics by formulating and considering different methods.Euler,Runge Kutta,and a Non-standardfinite difference(NSFD)method are developed for the same problem.Numerical experiments are performed at disease-free and endemic equilibria points at different time step sizes‘ℎ’.The results reveal that,unlike Euler and Runge Kutta,which fail for large time step sizes,the proposed Non-standardfinite difference(NSFD)method gives a convergence solution for any time step size.Our proposed numerical method is bounded,dynamically con-sistent,and preserves the positivity of the continuous solution,which are essential requirements when modeling a prevalent disease.

Nosocomial infections:Epidemiology,prevention,control and surveillance

Nosocomial infections or healthcare associated infections occur in patients under medical care.These infections occur worldwide both in developed and developing countries.Nosocomial infections accounts for 7% in developed and 10% in developing countries.As these infections occur during hospital stay,they cause prolonged stay,disability,and economic burden.Frequently prevalent infections include central line-associated bloodstream infections,catheter-associated urinary tract infections,surgical site infections and ventilator-associated pneumonia.Nosocomial pathogens include bacteria,viruses and fungal parasites.According to WHO estimates,approximately 15% of all hospitalized patients suffer from these infections.During hospitalization,patient is exposed to pathogens through different sources environment,healthcare staff,and other infected patients.Transmission of these infections should be restricted for prevention.Hospital waste serves as potential source of pathogens and about 20%–25% of hospital waste is termed as hazardous.Nosocomial infections can be controlled by practicing infection control programs,keep check on antimicrobial use and its resistance,adopting antibiotic control policy.Efficient surveillance system can play its part at national and international level.Efforts are required by all stakeholders to prevent and control nosocomial infections.

Analytical study of Cattaneo–Christov heat flux model for a boundary layer flow of Oldroyd-B fluid

We investigate the Cattaneo-Christov heat flux model for a two-dimensional laminar boundary layer flow of an incompressible Oldroyd-B fluid over a linearly stretching sheet. Mathematical formulation of the boundary layer problems is given. The nonlinear partial differential equations are converted into the ordinary differential equations using similarity transformatioris. The dimensionless velocity and temperature profiles are obtained through optimal homotopy analysis method （OHAM）. The influences of the physical parameters on the velocity and the temperature are pointed out. The results show that the temperature and the thermal boundary layer thickness are smaller in the Cattaneo-Christov heat flux model than those in the Fourier＇s law of heat conduction.

Coastal Biomass Mapping Through Subpixel Classification Technique—A Technique of Segregating Materials Within Pixel

World Wide Fund for Nature(WWF)scientists in collaboration with regional experts around the world, have developed the Global 200 Ecoregions Program, the first comparative analysis of biodiversity to cover biologically outstanding terrestrial,freshwater and marine habitats,spanning five continents and all the world’s oceans.Due to its immense importance,Indus Delta Ecoregion is one of the G200 Ecoregions of

Heat transfer analysis in the flow of Walters' B fluid with a convective boundary condition

Radiative heat transfer in the steady two-dimensional flow of Walters＇ B fluid with a non-uniform heat source/sink is investigated. An incompressible fluid is bounded by a stretching porous surface. The convective boundary condition is used for the thermal boundary layer problem. The relevant equations are first simplified under usual boundary layer assumptions and then transformed into a similar form by suitable transformations. Explicit series solutions of velocity and temperature are derived by the homotopy analysis method （HAM）. The dimensionless velocity and temperature gradients at the wall are calculated and discussed.

Adsorption of Chromium (VI) Using Nano-ZnO Doped Scrap Tire-Derived Activated Carbon

Nowadays, nano mineral modified biochars show a promising adsorption capacity for pollutants removals by combining the advantages of porous structure of biochar and unique property of nano minerals. In this work, nano-zinc oxide doped scrap tire derived activated carbon (nZnO-STAC) was synthesized by wetness impregnation method. Equilibrium data were analyzed using Langmuir and Freundlich isotherm models while the kinetics of the process were examined using Lagergren Pseudo-first and second order, intraparticle diffusion and Elovich kinetic models. Characterization of the activated carbon by Powder X-ray Diffraction (PXRD). The surface groups present on the activated carbon surface were determined using the Fourier Transform Infra-Red Spectroscopy (FTIR) analysis. Optimization studies were carried out to determine the effects of pH, initial metal concentration, adsorbent dosage, contact time and adsorbent particle size on the Cr (VI) removal efficiency. The results showed optimum Cr (VI) removal at pH 3, 10 mg/L concentration, 120 minutes of contact using 1000 - 1400 μm adsorbent particle size at a dosage of 2.5 g/L. The adsorbent structure was found to be predominantly amorphous. The chromium removal efficiency of the adsorbent was around 81.6%. Of the tested kinetic models, the pseudo-second order model exhibited the best fit with the experimental data with an R2 value of 0.9744. This study clearly demonstrates the feasibility of using the nano-ZnO doped scrap tyre derived activated carbon adsorbent for the remediation of chromium (VI) polluted industrial wastewaters.

Parametic Model for Optimization of Battery Capacity and Power Transmitters of On-line Electric Vehicles in Closed/Open Environments

An on-line electric vehicle(OLEV)uses a wireless charging phenomenon,in which power transmitters are installed beneath the road and the OLEV’s battery is charged remotely.This paper deals with the optimization of two key economic and design parameters,i.e.,the size of the battery and the power transmitters allocation.A complete model configuration of the OLEV system,including the vehicle design and power transmitter,is implemented using MATLAB/Simulink.The battery’s state of charge(SOC)rises and drops according to the vehicle’s velocity and power collection and consumption.The mixed integer programming(MIP)model is used for cost calculation.Therefore,with the help of the SOC graph and MIP model,the battery size and the number of power transmitters,along with their placements,are optimized.The proposed model is applicable to both closed and open environments as it accepts both regulated and deregulated velocities.Two test cases are performed for this purpose.The first test case deals with regulated velocity for which we have applied the KAIST campus OLEV’s velocity along with its 13 kWh battery size and 4 power transmitters,and then applied the suggested solution with the same velocity and route i.e.,8 power transmitters with shorter lengths and reduced battery size(3.25 kWh;one-fourth of the first case).SOC is found within limits at the end of the route,saving$1600 and validating the proposed model in this paper.For the second test case,we use deregulated velocity and optimize both parameters,using the same approach.

Phase transitions and degradation/oxidation mechanisms in lead-free CsSnI_(3)halide perovskites

Halide perovskites possess ultra-low thermal conductivity and show high potential for thermoelectric devices.The chemical properties and molecular structure of halide perovskite materials are not completely stable under ambient conditions,which hinders their use in thermoelectric generators.Changes in the properties of bulk halide perovskite thermoelectrics are accompanied by partial phase transitions and surface oxidation processes.In this paper,we conducted a comprehensive study of the transport and structural properties of CsSnI_(3),which were pristine by vacuum melting followed by spark plasma sintering.The research results on the electrical transport of these materials revealed that exposure to an inert atmosphere does not deteriorate stability and the properties of the materials remain unchanged.However,prolonged exposure to air leads to a significant degradation of the electrical transport properties.Contrary to thin-film samples,the shift to the double perovskite structure from the perovskite one is limited to a specific surface layer.This change significantly influences the electrical transport of the material while maintaining the essential properties of both perovskite types.

Triphenylamine-AIEgens photoactive materials for cancer theranostics

Triphenylamine(TPA)-based aggregation-induced emission luminogens(TPA-AIEgens),a type of photoactive material utilizing the typical TPA moiety,has recently attracted increasing attention for the diagnostics and treatment of tumors due to their remarkable chemo-physical performance in optoelectronic research.TPA-AIEgens are distinguished from other photoactive agents by their strong fluorescence,good sensitivity,high signal-to-noise ratio,resistance to photobleaching,and lack of high concentration or aggregation-caused fluoresce quenching effects.In this review,we summarize the current advancements and the biomedical progress of TPA-AIEgens in tumor theranostics.First,the design principles of TPAAIEgens photoactive agents as well as the advanced targeting strategies for nuclei,cell membranes,cell organelle and tumors were introduced,respectively.Next,the applications of TPA-AIEgens in tumor diagnosis and therapeutic techniques were reviewed.Last,the challenges and prospects of TPA-AIEgens for cancer therapy were performed.The given landscape of the TPA-AIEgens hereby is meaningful for the further design and utilization of the novel photoactive material,which could be beneficial for the development of clinic applications.

Milk phospholipids-based nanostructures functionalized with rhamnolipids and bacteriocin:Intrinsic and synergistic antimicrobial activity for cheese preservation

Milk fat globule membrane (MFGM) phospholipids-based nanostructures were developed and their functionalization with rhamnolipids (RLs) was carried out to enhance the preservation of cheese against resistant foodborne pathogens i.e.,Listeria monocytogenes and Escherichia coli .Void (without nisin) and nisin-loaded RLs functionalized MFGM nanostructures (RLs-MFGM-NS) were fabricated by ultrasonication-assisted self-assembly method.Cubic morphology of void and loaded RLs-MFGM-NS and pristine MFGM nanostructures (MFGM-NS) was observed under scanning electron microscopy (SEM),which indicated uniform size ranging from 43 nm (void RLs-MFGM-NS) to 194 nm (loaded RLs-MFGM-NS).FTIR analyses confirmed the electrostatic interaction,predominantly H-bonding and linkage of carboxyl ester group of MFGM with C–H group in RLs after functionalization of NS.Furthermore,quantitative antimicrobial assay on cheese slices confirmed the broad-spectrum potential of intrinsically active nanostructures (due to RLs) having synergistic activity with nisin against L.monocytogenes and E.coli .Hence,nisin-loaded RLs-MFGM-NS can be applied as promising bioactive additives for sustained preservation of cheese.