Shear deformable beams in contact with an elastic half-plane

The present work deals with the contact problem of a Timoshenko beam bonded to an elastic semi-infinite substrate under different loading conditions. The analysis allows investigating the effects induced by shear compliance of the beam, the stress intensity factors ad the beam edges as well as the singular nature of the interfacial stresses

Mechanical performance and crack pattern analysis of aged Carbon Fabric Cementitious Matrix (CFRCM) composites

We discuss the effect of environmental exposure on mechanical performance of impregnated Carbon Fabric Reinforced Cementitious Matrix (CFRCM) composite. Following the recently published ICC-ES AC434 guidelines, mechanical performance of prismatic composite specimens is determined on the basis of tensile uni-axial tests. Exposure to saline and alkaline aqueous solutions is considered at 28- as well as 60-day curing time. Special emphasis is placed on crack pattern evaluation as a mean to gain better insight into matrix/fabric bond quality. To this aim, the evolution of the average crack spacing and of the average crack width is determined as a function of strain for all test environments and curing times. It is found that curing time plays a significant role in mitigating the detrimental effect of aggressive environments. Furthermore, the average crack spacing provides a very reliable measure of matrix/fabric bond degradation at all test stages

Use of Neem (Azadirachta Indica) Seeds as Filler in Natural Rubber Compounding

The importation of carbon black (a petroleum product) for the reinforcement of Natural Rubber (NR) is very expensive. Therefore, the need to source alternative materials locally becomes necessary. Neem seed (NS) was evaluated as reinforcing fillers in the compounding of NR. NS were collected, cleaned, dried, milled and some part of it was carbonized at 2500C. The Carbonized Neem Seed (CNS) and Uncarbonized Neem Seed (UNS) powders were sieved using 90μm mesh size and then characterized. These were then used as fillers in varying proportions (0%, 15%, 30%, 50% and 100%) with Carbon Black (CB) for the compounding of NR. The physicomechanical properties including tensile strength, elongation at break of the vulcanizates were determined. Scanning Electron Microscopy (SEM) was also used to analyze the morphology of the blend in the vulcanizates with 100% CNS, UNS and CB. The loss on ignition for the CNS was found to be 89.5 while that of UNS was 69.8. The physicomechanical analysis carried out on the vulcanizates showed better properties for the carbonized samples than the uncarbonized ones. The 15% and 30% CNS reinforced better than 100% CB as shown in the results. The SEM result showed a better dispersion of the CB into the vulcanizate with 100% CNS and UNS

Thermophysical Properties of Gmelina Arborea Biodiesel

The depletion of petroleum reserves, rising cost of conventional fuels and the ill effect of emission from the use of fossil fuel on human health and environment have driven scientific research towards the development of alternative source of fuels such as biofuel and biodiesel. Biodiesel is a fuel from a renewable sources and it has the potential of being used as an alternative to fossil diesel in compression ignition engine. Some of the challenges encountered in the use of biodiesel in compression ignition engine are its availability, use of edible oil for its production, cost of biodiesel feedstock and unfavorable properties of biodiesel such as its high viscosity. Presently, there is a search for more inedible oil seeds since the available inedible feedstock are still not enough to replace more than 20 - 25% of the total transportation fuels. The thermophysical properties of the biodiesel which vary from feedstock have a significant impact on the combustion process thereby affecting the overall engine performance and emissions. The aim of this study is to test the compatibility of biodiesel from Gmelina arborea seed oil in the compression ignition engine through its thermophysical properties. The biodiesel was produced using transesterification method and the thermophysical properties tests were carried out. The results showed that the density and viscosity of Gmelina arborea seed oil was 868.8 kg/m2 (at 27.5°C) and 1.882(mm)2/s (at 40.0°C) respectively. It also showed that the biodiesel obtained had a density and viscosity value of 821.2 kg/m3 (at 27.5°C) and 0.794 9 (mm)2/s (at 40.0°C) respectively. Comparing these results with other biodiesel, it was observed that Gmelina arborea oil has a lower viscosity and density than other biodiesel from different feedstocks; therefore it has potential to perform better in the diesel engine in comparison to other biodiesel

Improved Drilling Efficiency via Enhanced Water Based Mud in the Niger Delta

This study focuses on latest advances in water based mud as a potential for the Niger Delta, its impact on drilling efficiencies and well productivity. Recently, New mud additives are been developed to enhance the rheology of water based mud to deliver the same characteristics and reliability of an oil based mud when considering the Niger Delta geology. Due to the challenges with Water Based Mud in respect to chemistry and suitability, Oil Based Mud (OBM) has become the main type of drilling fluid in deeper sections during drilling campaign in the Niger Delta. But the use of OBM as come with some challenges that has necessitated the further research and development of Water Based Mud rheology that can deliver the same results as OBM. Some of the challenges associated with the use of OBM include but not limited to high cost and management, contamination of OBM in the storage site during drilling activities, logistics complexity, environmental impact from spills and disposal, and impact on well productivity and reservoir management. In countries such as Ghana, Columbia, Oman, Mexico, Enhanced WBM mud has been used and is still being used in drilling to deep depths (8000ft-10000ft)TVD in formations with similar geology with that of the Niger Delta. Sample wells will be reviewed from one of these regions for the project and they will be used to show the evolving new technologies and techniques in WBM rheology formulation. This study is channeled to label the engineered properties of the mud, mud composition, its effects on drilling efficiency and well productivity, challenges encountered, the concept for an enhancement, added advantage in comparison to OBM, comparative cost advantage. It was discovered that Enhanced WBM has an added advantage hence leading to a reduction in pollution trends in the Niger Delta and cost effectiveness. Other advantages include addressing to an extent the challenges encountered with WBM such as (inhibition, hydration and solids control) leading to an enhanced well productivity and ultimately affects the overall cost of well delivery

Development and property evaluation of alkyd resins from watermelon (Citrullus lanatus) seed oil

62-67Watermelon Seed Oil (WSO) has been investigated for its suitability in the development of alkyds. Chemical method is used to extract the oil, and the WSO's physicochemical properties are determined. The alcoholysis-esterification method is used to prepare two grades of alkyds containing 30 percent WSO (alkyd I) and 60 percent WSO(alkyd II).The progress of the reaction is monitored by determining the volume of water of condensation and acid value as the reaction progresses. Film properties of the prepared alkyd are determined. The results of the physicochemical properties of the WSO reveal an iodine value of 119.38 gI2/100g indicating that it is semi-drying oil and can serve as a modifier for alkyd resins production for the paint industry. Alkyd I has a higher acid value, a greater degree of polymerization and extent of the polymerization than alkyd II, according to the results. Alkyd II produce a harder film than that of alkyd I as observed from the scratch hardness test. Also, both alkyd show good flexibility properties and have good impact resistance on the coated panel. The present study, therefore, suggests that WSO can be considered as a modifier for alkyd resins production for the paint industry

COMPARATIVE AND EXPERIMENTAL STUDY ON THE PROPERTIES AND POTENCY OF SYNTHESIZED ORGANIC AND MINERAL SUNSCREEN MOISTURIZER

This research work aims at synthesizing two different types of moisturizers: a body butter and a lotion. Based on the methodology, three samples of the body butter and lotion was produced, by varying the percentage of zinc oxide and Shea butter, the samples were analyzed with a UV- spectrophotometer to determine the transmittance and absorbance strength which was in turn used to determine the SPF. Vaseline which is a standard organic lotion was also analyzed to determine the transmittance, absorbance strength and SPF. The results were compared. Of all the moisturizers synthesized in this research, the lotion which had 10% zinc oxide had the highest absorbance strength, and hence the highest SPF. Therefore, it was concluded that a minimum of 10% zinc oxide should be used in the production of sunscreen moisturizers to provide moderate sun protectio

Aggression Following Traumatic brain injury: Effectiveness of Risperidone (AFTER): study protocol for a feasibility randomised controlled trial

Background: Traumatic brain injury (TBI) is a major public health concern and many people develop long-lasting physical and neuropsychiatric consequences following a TBI. Despite the emphasis on physical rehabilitation, it is the emotional and behavioural consequences that have greater impact on people with TBI and their families. One such problem behaviour is aggression which can be directed towards others, towards property or towards the self.Aggression is reported to be common after TBI (37–71%) and causes major stress for patients and their families.Both drug and non-drug interventions are used to manage this challenging behaviour, but the evidence-base for these interventions is poor and no drugs are currently licensed for the treatment of aggression following TBI. The most commonly used drugs for this purpose are antipsychotics, particularly second-generation drugs such as risperidone. Despite this widespread use, randomised controlled trials (RCTs) of antipsychotic drugs, including risperidone, have not been conducted. We have, therefore, set out to test the feasibility of conducting an RCT of this drug for people who have aggressive behaviour following TBI. Methods/design: We will examine the feasibility of conducting a placebo-controlled, double-blind RCT of risperidone for the management of aggression in adults with TBI and also assess participants’ views about their experience of taking part in the study. We will randomise 50 TBI patients from secondary care services in four centres in London and Kent to up to 4 mg of risperidone orally or an inert placebo and follow them up 12 weeks later. Participants will be randomised to active or control treatment in a 1:1 ratio via an external and remote web-based randomisation service. Participants will be assessed at baseline and 12-week follow-up using a battery of assessment scales to measure changes in aggressive behaviour (MOAS, IRQ) as well as global functioning (GOS-E, CGI), quality of life (EQ-5D-5L, SF-12) and mental health (HADS). We will also assess the adverse effect profile with a standard scale (UKU) and collect available data from medical records on blood tests (serum glucose/HbA1c, lipid profile, prolactin), and check body weight and blood pressure. In addition completion of the MOAS and a check for any new or worsening side-effect will be completed weekly and used by the prescribing clinician to determine continuing dosage. Family carers’ well being will be assessed with CWSQ. Service use will be recorded using CSRI. A process evaluation will be carried out at theend of the trial using both qualitative and quantitative methodology. Discussion: Aggressive behaviour causes immense distress among some people with TBI and their families. By examining the feasibility of a double-blind, placebo-controlled RCT, we aim to discover whether this approach can successfully be used to test the effects of risperidone for the treatment of aggressive behaviour among people with aggression following TBI and improve the evidence base for the treatment of these symptoms. Our criteria for demonstrating success of the feasibility study are: (1) recruitment of at least 80% of the study sample, (2) uptake of intervention by at least 80% of participants in the active arm of the trial and (3) completion of follow-up interviews at 12 weeks by at least 75% of the study participants

An Assessment of the Role of Florida Pharmacists in the Administration of Inactivated Influenza Vaccine to Pregnant Women

The influenza vaccine is a safe and effective vaccine in preventing influenza infection in the general population. The Centers for Disease Control (CDC) recommend that pregnant women receive influenza inactivated vaccine (IIV) due to the high morbidity and mortality associated with influenza infection in pregnant women. Despite the recommendation, the U.S. national influenza vaccine uptake rates among pregnant women continue to remain low. Studies have shown barriers to influenza vaccine uptake in pregnant women to include issues with access, unavailability of vaccine, and lack of time during prenatal visits. These barriers can be overcome using pharmacists because, among healthcare providers, pharmacists are the most accessible; approximately 250 million individuals make a trip to the pharmacy every week, however, there are few qualitative studies on pharmacists perspectives on the role they can play to increase influenza vaccine uptake in pregnant women. This study aims to qualitatively study explore: (a) The course content related to influenza immunization and how pharmacy students perceive it, and (b) Influenza vaccine administering practices among licensed pharmacists. The objectives will be achieved qualitatively through the use of in-depth interviews and focus groups. Exploration of pharmacy school curriculum revealed a need for pregnancy-specific immunization content. Qualitative interviews with licensed pharmacists revealed that most pharmacists believe they have a role to play in providing influenza immunization to pregnant women. This study suggests that systematically implementing more pregnancy-specific content into pharmacy school curricular would be effective in intervening with pharmacy students. Findings also indicate the need for continued education intervention with practicing pharmacists, as access to immunization services should not be mitigated by a lack of knowledge and personal beliefs