Interpreting Measurements of Small Strain Elastic Shear Modulus under Unsaturated Conditions

Bender element testing of unsaturated isotropically compacted speswhite kaolin samples was used to investigate the variation of small strain elastic shear modulus G under unsaturated conditions. Testing was performed in a suction-controlled triaxial cell and involved combinations of isotropic loading and unloading stages and wetting and drying stages. Analysis of the experimental results indicated that the variation of G could be represented by a simple expression involving only mean Bishop’s stress p* and specific volume v, with the only significant mismatches between measured and predicted values of G occuring at the end of final unloading. No significant improvement of fit was achieved by incorporating additional dependency on degree of saturation Sr or a bonding parameter ζ. The proposed expression for G reverts to a well-established form for saturated soils as Sr tends to 1

Filtration and oxidation characteristics of a diesel oxidation catalyst and a catalyzed particulate filter : development of a 1-D 2-layer model

The emissions, filtration and oxidation characteristics of a diesel oxidation catalyst (DOC) and a catalyzed particulate filter (CPF) in a Johnson Matthey catalyzed continuously regenerating trap (CCRT ®) were studied by using computational models. Experimental data needed to calibrate the models were obtained by characterization experiments with raw exhaust sampling from a Cummins ISM 2002 engine with variable geometry turbocharging (VGT) and programmed exhaust gas recirculation (EGR). The experiments were performed at 20, 40, 60 and 75% of full load (1120 Nm) at rated speed (2100 rpm), with and without the DOC upstream of the CPF. This was done to study the effect of temperature and CPF-inlet NO2 concentrations on particulate matter oxidation in the CCRT ®. A previously developed computational model was used to determine the kinetic parameters describing the oxidation characteristics of HCs, CO and NO in the DOC and the pressure drop across it. The model was calibrated at five temperatures in the range of 280 – 465° C, and exhaust volumetric flow rates of 0.447 – 0.843 act-m3/sec. The downstream HCs, CO and NO concentrations were predicted by the DOC model to within ±3 ppm. The HCs and CO oxidation kinetics in the temperature range of 280 - 465°C and an exhaust volumetric flow rate of 0.447 - 0.843 act-m3/sec can be represented by one ’apparent’ activation energy and pre-exponential factor. The NO oxidation kinetics in the same temperature and exhaust flow rate range can be represented by ’apparent’ activation energies and pre-exponential factors in two regimes. The DOC pressure drop was always predicted within 0.5 kPa by the model. The MTU 1-D 2-layer CPF model was enhanced in several ways to better model the performance of the CCRT ®. A model to simulate the oxidation of particulate inside the filter wall was developed. A particulate cake layer filtration model which describes particle filtration in terms of more fundamental parameters was developed and coupled to the wall oxidation model. To better model the particulate oxidation kinetics, a model to take into account the NO2 produced in the washcoat of the CPF was developed. The overall 1-D 2-layer model can be used to predict the pressure drop of the exhaust gas across the filter, the evolution of particulate mass inside the filter, the particulate mass oxidized, the filtration efficiency and the particle number distribution downstream of the CPF. The model was used to better understand the internal performance of the CCRT®, by determining the components of the total pressure drop across the filter, by classifying the total particulate matter in layer I, layer II, the filter wall, and by the means of oxidation i.e. by O2, NO2 entering the filter and by NO2 being produced in the filter. The CPF model was calibrated at four temperatures in the range of 280 – 465 °C, and exhaust volumetric flow rates of 0.447 – 0.843 act-m3/sec, in CPF-only and CCRT ® (DOC+CPF) configurations. The clean filter wall permeability was determined to be 2.00E-13 m2, which is in agreement with values in the literature for cordierite filters. The particulate packing density in the filter wall had values between 2.92 kg/m3 - 3.95 kg/m3 for all the loads. The mean pore size of the catalyst loaded filter wall was found to be 11.0 µm. The particulate cake packing densities and permeabilities, ranged from 131 kg/m3 - 134 kg/m3, and 0.42E-14 m2 and 2.00E-14 m2 respectively, and are in agreement with the Peclet number correlations in the literature. Particulate cake layer porosities determined from the particulate cake layer filtration model ranged between 0.841 and 0.814 and decreased with load, which is about 0.1 lower than experimental and more complex discrete particle simulations in the literature. The thickness of layer I was kept constant at 20 µm. The model kinetics in the CPF-only and CCRT ® configurations, showed that no ’catalyst effect’ with O2 was present. The kinetic parameters for the NO2-assisted oxidation of particulate in the CPF were determined from the simulation of transient temperature programmed oxidation data in the literature. It was determined that the thermal and NO2 kinetic parameters do not change with temperature, exhaust flow rate or NO2 concentrations. However, different kinetic parameters are used for particulate oxidation in the wall and on the wall. Model results showed that oxidation of particulate in the pores of the filter wall can cause disproportionate decreases in the filter pressure drop with respect to particulate mass. The wall oxidation model along with the particulate cake filtration model were developed to model the sudden and rapid decreases in pressure drop across the CPF. The particulate cake and wall filtration models result in higher particulate filtration efficiencies than with just the wall filtration model, with overall filtration efficiencies of 98-99% being predicted by the model. The pre-exponential factors for oxidation by NO2 did not change with temperature or NO2 concentrations because of the NO2 wall production model. In both CPF-only and CCRT ® configurations, the model showed NO2 and layer I to be the dominant means and dominant physical location of particulate oxidation respectively. However, at temperatures of 280 °C, NO2 is not a significant oxidizer of particulate matter, which is in agreement with studies in the literature. The model showed that 8.6 and 81.6% of the CPF-inlet particulate matter was oxidized after 5 hours at 20 and 75% load in CCRT® configuration. In CPF-only configuration at the same loads, the model showed that after 5 hours, 4.4 and 64.8% of the inlet particulate matter was oxidized. The increase in NO2 concentrations across the DOC contributes significantly to the oxidation of particulate in the CPF and is supplemented by the oxidation of NO to NO2 by the catalyst in the CPF, which increases the particulate oxidation rates. From the model, it was determined that the catalyst in the CPF modeslty increases the particulate oxidation rates in the range of 4.5 – 8.3% in the CCRT® configuration. Hence, the catalyst loading in the CPF of the CCRT® could possibly be reduced without significantly decreasing particulate oxidation rates leading to catalyst cost savings and better engine performance due to lower exhaust backpressures

A Histopathological Study And Antioxidant Effect Of Ginger To Diminishing Poisoning Lead Acetate-Induced Hepatopathy In Rabbits For Three Months.

Lead acetate is an example of heavy metals that for decades being known for its adverse effects on various body organs and systems such that their functions are compromised. The present study, carried out to evaluate histopathological changes in rabbits liver induced by lead acetate toxicity and to investigate the therapeutic effects of ginger against lead poisoning. Ginger is source of antioxidants was administered orally to prevent the adverse effects of lead acetate. Thirty rabbits, randomized into 3 groups (n = 10), were used for this study. Animals in group (A) served as the control and were drinking distilled water. Animals in groups (B) and (C) were drinking 2% lead acetate. Group (C) animals were, in addition to drinking lead acetate, treated with 100 mg/kg/rabbit of ginger. All treatments were for 3 months. The obtained results showed that lead acetate caused histopathological changes were seen in the liver such as (vacuolation, degeneration, fibrosis and inflammation) and a significant reduction in plasma superoxide dismutase and catalase activity, but a significant increase in plasma malondialdehyde concentration, using ginger cause to modified these harmful effects. These findings lead to the conclusion that ginger significantly decreased the adverse harmful effects of lead acetate exposure on the liver as well as ginger may exert its protective actions against lead induced histopathological changes in liver tissue. Keywords: Ginger, Lead acetate and hepatopathy

Pathogenesis of IL-6 and potential therapeutic of IFN-γ in COVID-19

The elevated inflammatory cytokines suggest that a cytokine storm, also known as cytokine release syndrome (CRS), may play a major role in the pathology of pandemic Coronavirus Disease (COVID-19) leading to cause Acute respiratory distress syndrome (ARDS) and multiple organ dysfunction then death. However, there was a controversial efficacy of corticosteroids in the treatment of COVID-19 induced cytokine release syndrome (CRS). Novel therapies to treat COVID-19-induced CRS become urgent needed. One of the most common cytokine that showed to be critical in the COVID-19 is the IL-6 and this article discuss the pathogenesis of this cytokine in severe acute respiratory syndrome (SARS). Also, this article proposes to utilize interleukin-6 (IL-6) blockade and potential therapeutic effect of IFN-γ to manage COVID-19-induced CRS and discuss several factors that should be taken into consideration for its clinical application. DOI: http://dx.doi.org/10.5281/zenodo.400424

The Accountant's Ethical Code of Conduct and Moral Reasoning from an Islamic Environment: Case in Yemen

An ethical code of conduct is developed to guide behaviors of members in or of organizations. Accountants, in this context, are not an exception. The availability of such ethical code of conduct is extremely important for both accountants and users of accounting information. However, currently in Yemen, there is no ethical code of conduct for Yemeni professional accountants. It is also equally important to know how Yemeni professional accountants perceive prescriptively and deliberatively on issues related to the ethical code of conduct. Hence, two phases of study were carried out to tap the issues. The first phase was sought to address the question of what constitutes the ethical code of conduct among Yemeni professional accountants. Data were collected from 386 users of accounting information in Yemen. The study employed interdependency analysis to reveal and confirm the domain of the accountants' ethical code of conduct. Results show that the ethical code of conduct consists of several ethical constructs. The second phase of the study was to know to what extent Yemeni professional accountants behave ethically at work. This is important because Islam emphasizes consistency between thought and action. Data were collected from 138 professional accountants in four main cities of Yemen i.e. Sana'a, Hadhramout, Taiz, and Aden. Results showed that Yemeni professional accountants exhibit higher level of moral reasoning beyond the conventional level. The findings of this study contribute to the body of knowledge by providing an Islamic perspective to the ethical issues which has similarities and differences vis-a-vis the Western perspective

Design and Implementation of an Electrical Lift Controlled using PLC

This paper represents the possibility of controlling an electrical elevator model using PLC and studying some parameters to ensure its work, this model have been designed and constructed to perform a completed elevator work in an automating technique according to its programming and controlling method that making the connecting much more easier and safer than real relays and complicated wiring method. As well as the small DC motor drive (gear box) electrical motor that used  to drive the elevator cabinet which made the transition from floor to floor much smoother and much efficient than the traditional elevators

The Structure of Verbless Sentences in Northern Kurdish

In the study of syntax, a special attention is given to the verb as the main constituent in the structure of the predicate. However, there exists some constructions in which a noun, adjective or an adverb are the main constituents in the predicate. In Kurdish literature, there is a debate on the analysis of these verbless constructions. On one hand, they are considered nominal sentences which do not contain a verbal element. On the other hand, they are considered small verbal sentences in which the agreement markers on the predicate act as verbal element. The study is an attempt to analyse the structure of these verbless constructions within the framework of minimal program (Chomsky, 1995) in one of the widely spoken variety of Kurdish, Northern Kurmanji, Bahdinani subdialect. It contributes to resolve the existent debate in Kurdish linguistics concerning the structure of these constructions. Additionally, it contributes to the typological variation in the syntactic properties of these constructions in Kurdish

The Phonological Word and Stress Shift in Northern Kurmanji Kurdish

It is generally believed that stress in Kurdish is word-final. However, closer examination reveals several kinds of exceptions. This study proposes a unified analysis of regular and irregular stress patterns in Northern Kurmanji. It analyses the stress-assignment rule on the basis of a framework of prosodic phonology that divides the representation of speech into hierarchically organised units. It proposes the phonological word as the domain of stress rule and a number of other phonological processes such as glide insertion, resyllabification, vowel deletion, vowel shortening. Additionally, it proposes the cyclic analysis as the method of the rule application. Cases of stress rule violation are considered as instances of stress-shift which are conditioned by different phonological and syntactical factors or they can be accounted for by using recursive structure and phrase stress rule

Quantitative Sequestration of Anthropogenic Pollutants by Marine Microalgae

Due to increased industrialization, the release of anthropogenic pollutants in the environment is increasing and the fate of these pollutants has become a global concern. Marine phytoplankton act as a considerable sink of many anthropogenic pollutants. However, chemical analyses of the biosequestration process often encounter challenges due to many simultaneously interacting chemical and biological parameters. This dissertation is motivated by understanding phytoplankton’s sequestration of anthropogenic pollutants by linking all the interactions between microalgae and their environment.The sequestration of greenhouse gas CO2 and its utilization for biomass production by marine microalgae was investigated by developing novel modeling methodologies with required microscopic spatial resolution. The validation experiments indicated that the model can accurately describe the chemically complex relation between atmospheric CO2 and resulting biomass. Moreover, few applications of the model were presented to predict the impact of future environmental changes on the ecosystem.In order to assess microalgae’s CO2 sequestration a straightforward indicator, intracellular carotene quantity, was proposed. To accomplish this, intracellular carotene was measured by a combination of fluorescence spectroscopy and flow cytometry. By relating cells’ internal response (carotenoid) to external chemical changes (atmospheric CO2), a slowdown in microalgae’s CO2 sequestration was indicated by an increase of intracellular carotene quantity.The last research topic was motivated by understanding the effect of two heavy metal pollutants (copper and nickel), on the uptake and biomass production by marine microalgae. The uptake of heavy metal by the contaminated cultures was quantified by inductively coupled plasma optical emission spectroscopy. This investigation suggested that the uptake of heavy metals and algal growth was strongly influenced by heavy metal. Furthermore, contaminated cells suffered significant intracellular damage due to the presence of heavy metal