Silver Nanoclusters And Nanofractals In Natural Rubber Matrix.

Silver nanocrystals were synthesized in natural rubber matrix via UV irradiation technique. A high intensity UV light with a wavelength below 300 nm was used to reduce the silver ions in the natural rubber matrix

Electrical and Thermal Behavior of Copper-Epoxy Nanocomposites Prepared via Aqueous to Organic Phase Transfer Technique

The preparation, electrical, and thermal behaviors of copper-epoxy nanocomposites are described. Cetyltrimethylammonium bromide- (CTAB-) stabilized copper (Cu) particles were synthesized via phase transfer technique. Isopropanol (IPA), sodium borohydride (NaBH4), and toluene solution of diglycidyl ether of bisphenol A (DGEBA) were used as transferring, reducing agent, and the organic phase, respectively. The UV-Vis absorbance spectra of all the sols prepared indicate that the presence of Cu particles with the particles transfer efficiency is ≥97%. The amount, size, and size distribution of particles in the organosol were dependent on the content of organic solute in the organosol. The composites were obtained upon drying the organosols and these were then subjected to further studies on the curing, thermal, and electrical characteristic. The presence of Cu fillers does not significantly affect the completeness of the composite curing process and only slightly reduce the thermal stability of the composites that is >300◦C. The highest conductivity value of the composites obtained is 3.06 × 10−2 S cm−1

Development of PAN (personal area network) for Mobile Robot Using Bluetooth Transceiver

In recent years, wireless applications using radio frequency (RF) have been rapidly evolving in personal computing and communications devices. Bluetooth technology was created to replace the cables used on mobile devices. Bluetooth is an open specification and encompasses a simple low-cost, low power solution for integration into devices. This research work aim was to provide a PAN (personal area network) for computer based mobile robot that supports real-time control of four mobile robots from a host mobile robot. With ad hoc topology, mobile robots may request and establish a connection when it is within the range or terminated the connection when it leaves the area. A system that contains both hardware and software is designed to enable the robots to participate in multi-agent robotics system (MARS). Computer based mobile robot provide operating system that enabled development of wireless connection via IP address

Comparative study on the effectiveness acetaminophen and diclofenac on pretreatment in the relief of pain after out-patient surgery

The aim of this study is to evaluate and quantify the pain relief after minor surgery when certain analgesics are used before surgery. Double blind study was conducted on 300 outpatient surgery patients who were allocated into two groups. Before surgery, 100 mg of acetaminophen was given to one group and 75 mg of diclofenac to the other one. The pain level after surgery was measured and recorded in both groups by a ruler 10 cm using the Visual Analog Scale (VAS) method at intervals of 30 min, 1, 2 and 4 h after surgery. Also for the patients with VAS more than 7, it was recommended to administer IM 50-100 mg teramadole ampoule. Mean VAS in acetaminophen group was 5.28±1.17, 5.17 ±1.04, 4.47±1.05±, 3.97±1.09 while, in diclofenac group was 5.09±1.10, 5.10±1.024.27±1.05 and 3/73±1.07 at 0.5, 1, 2 and 4 h after surgery, respectively. In fact there was no significant difference in pain level after surgery between acetaminophen and diclofenac groups (p>0.05). Moreover, there was no significant difference in the effectiveness of pain relief induced by administering tramadol calmative ampoule along with acetaminophen and diclofenac groups (p>0.05). Acetaminophen results in as effective pain relief as diclofenac with or without tramadol calmative. Due to minimal side effects of acetaminophen when compared to other analgesics, like diclofenac, it is recommended to use acetaminophen for safe and efficient pain relief after outpatients surgeries

Developmental research of sustainable technologies to minimise problematic road embankment settlements

Challenging, problematic and non-uniform ground conditions are a night mare to geotechnical engineers tasked with the design and construction of buildings and transport infrastructure. These often suffer undesirable structural settlements. Designing within the current understanding of geotechnics; settlement in peat and organic soils need to be recognised to include the known “primary and secondary consolidation characteristics” and the lesser known “tertiary consolidation phase”. These eventually contribute cumulatively to the consequential uneven and hazardous “bumpy road” surfaces. Undulating flexible road pavements result primarily from the transference of the heavy self-weight of the embankment fill to yielding and non-uniform subgrade. The adoption of conventional design/repair methods such as pile, vertical drain, soil replacement and soil stabilisation are expensive and inappropriate in very soft ground conditions. These then lead to unjustifiably high and repetitive maintenance costs. There being no one quick fix solution for all; pragmatic research must necessarily identify the best/progressively improved practical and sustainable solution. A viable solution is to develop criteria and explore the concept of a “masonry arch bridge structure/lintel-column structure” and adopting sustainable materials through pragmatic searching for appropriate recyclable waste materials. This will lead to the basis for a sustainable, innovative, strong, stiff, permeable composite mat structure that can be used on soft and/or yielding ground conditions. Conceptual lightweight fill technology including the popularly used expanded polystyrene (EPS) and the innovative composite mats recently being developed by the research team are outlined

Flexural Strength Behavior of Composite UHPFC-Existing Concrete

Article Preview Article Preview Ultra high performance fiber concrete (UHPFC) is an advanced formula concrete that is proven to be more superior than conventional concrete because it embrace the qualities of steel and concrete. Therefore UHPFC properties which include high durability and strength are fully exploited in the research of rehabilitation and strengthening in concrete and even non-concrete structures. This article presents the findings of an experimental study carried out to examine the bonding strength behaviour between normal concrete (NC) substrate and UHPFC as a repair material, under flexural strength test by using third-point loading beam test method. Three types of NC substrate surface preparation were used: as-cast (without surface preparation) as a reference, wire-brushed, and sand-blasted. The flexural test results clearly indicated that all failures occurred through the NC substrate and no

Influence of sulfate and chloride on the mechanical properties of fired clay masonry wall

This paper presents the influence of aggressive environment on the mechanical properties of masonry systems. The investigation involved the measurement of strength and modulus of elasticity of single leaf brick masonry wall which were built from fired clay bricks in conjunction with designation (iii) mortar with proportions of 1: 1: 6 (OPC: lime: sand). After being constructed, the specimens were cured under polythene sheet for 14 days in a controlled environment room with 80 ± 5% relative humidity and temperature of 25 ± 2ºC. The specimens were then exposed to the solution containing sodium sulfate and sodium chloride. The strength and modulus of elasticity of the brickworks were determined at the ages of 28, 56 and 180 days. The strength and modulus of elasticity of the brickworks, unbonded bricks, and mortar prisms were determined at the ages of 28, 56 and 180 days to quantify the contribution of bricks and mortar on the deformation of the masonry walls. As a result, fired clay brickwork is not durable and deteriorate in the environment containing sodium sulfate but durable in sodium chloride. The deterioration of the brickwork clearly influenced by the deterioration of mortar joint. The present of sodium chloride also retarding the attack of sodium sulphate

Goal-Setting Learning Principles: a Lesson From Practitioner

One of the prominent theory was the goal-setting theory which was widely been used in educational setting. It is an approach than can enhance the teaching and learning activities in the classroom. This is a report paper about a simple study of the implementation of the goal-setting principle in the classroom. A clinical data of the teaching and learning session was then analysed to address several issues highlighted. It is found that the goal-setting principles if understood clearly by the teachers can enhance the teaching and learning activities. Failed to see the needs of the session will revoke the students learning interest. It is suggested that goal-setting learning principles could become a powerful aid for the teachers in the classroom

SYNTHESIS AND CHARACTERIZATION OF CdS IN DIOL VANILIN LIQUID CRYSTAL MONOMER

Nanocomposites comprising diol-vanilin and cadmium sulfide (CdS) has been synthesized via chemical precipitation method in ethanol at refluxed temperature (160 oC) for 12 hours. CdCl2. 2.5H2O and thiourea as cadmium and sulfide precursors respectively were employed. Diol vanilin is a thermotropic liquid crystal monomer which exhibits enantiotropic nematic metaphase texture when observed under polarizing microscope and confirmed by DSC thermal stability study. A series of different mass composition  of diol vanilin and CdS nanocomposites ranging from  0.1:1.0 till 1.0:1.0(w/w) were prepared and characterized using XRD, TEM, SEM-EDX, POM and DSC. The X-ray diffraction pattern (XRD) showed broad peaks due to the formation of cubic CdS nanoparticles in diol vanilin matrix. The nanocomposites at low mass composition  of CdS still maintained their nematic phase. However, the liquid crystal property was affected when the mass  composition  of CdS in nanocomposite was increased and the liquid crystal characteristic vanished when the mass composition  was at 0.6:1.0. .    Keywords: CdS, diol vanilin, thermotropic liquid crystal, nanocomposite