Study of Transition Metal Nitride Ti1-xZrxN Alloy at High Pressure

The structural properties of transition metal nitride using have been explored in the present paper. The study has been extended to Ti1-xZrxN alloy (0 ≤ x≤ 1) alloy and the effect of composition on structural, and elastic properties are investigated. Phase transition pressure and related volume collapses [ΔV (Pt)/V(0)] calculated from this approach are in good agreement with available literature for the parent compounds (x=0 and x=1). The present compounds exhibit in rock salt (NaCl) structure at ambient condition, it transforms to cesium chloride (CsCl) structure under high pressure. The results for the mixed crystal counter parts are also in fair agreement with experimental data generated from the application of Vegard’s law to data for the parent compounds. Keywords, Alloy, Crystal structure, Phase transitions, High pressure Elastic property

FABRICATION, DESIGN OPTIMIZATION, AND STRESS ANALYSIS OF MONO LEAF SPRING USING METAL-MATRIX COMPOSITES

Weight is an important and contributing factor in an automobile in improving riding qualities. About ten to twenty percent of the weight of the system is provided by the leaf spring alone. Composite materials have the major advantage of high strength to weight ratio, with continuously decreasing travel cost in addition to other advantages like excellent corrosive resistance, superior fatigue strength and high specific strain energy storage capacity. The present work aims to evaluate the usage of composite material for the leaf spring of automobiles in order to reduce the effective weight of the suspension system, by this it is expected to improve the riding qualities of the automobile. A composite mono-leaf spring weighing about 3kgs is used to replace a steel leaf spring whose weight is about 12kgs. The present study also aims to compare the performance of the composite leaf spring with that of the conventional steel leaf spring and to suggest the suitability of using composite materials in automobile industry. In this approach static and dynamic analysis were conducted with the help of ANSYS 16 analysis software. The performance results are compared with steel leaf spring. Finally it is concluded that the composite leaf spring, which is 70% less in weight, is performing better than conventional steel leaf spring. It allows the traveler running leaf springs to be consistent night after night without having to constantly measure, monitor and change their springs for loss of sagging. The initial cost is a value based on the incredible service life. The composite material is mainly used to reduce the weight and increase the strength, stiffness etc Stir casting process is mainly used to manufacturing of reinforced with metal matrix composite. The manufacturing of aluminum alloy based on stir casting method its used to one of the most economical method of processing MMC. The main project the operating parameter of the composite as its control the properties of the composite material. This paper present overview of stir casting process, parameter & preparation of MMC study on mechanical behavior of metal matrix composite with varies composition of reinforcement particles of graphite or Nano particle B4Cand Al2O3 composite produced by the stir casting technique. The leaf is modeled using CATIA modeling and finite element analysis is done for same model utilizing ANSYS 16.0 software for Aluminum (Al-B4C) and the results were discussed. Key words: Stir-Casting, Proces

Knowledge, attitude and practice on the usage of safety helmet among oil palm harvesters

Safety helmet become vital personal protective equipment especially in the plantation in preventing the head from injury. This study evaluate the knowledge, attitude and practice on safety helmet usage among harvesters, the association between knowledge, attitude and practice of safety helmet usage with head injury; and the significant differences of the safety helmet practices before and after the intervention. A cross-sectional study was conducted among 109 harvesters in two oil palm plantation located in Selangor, Malaysia. A set of questionnaire was used to collect the socio demographic background data, knowledge, attitude and practice on the usage of safety helmet. An intervention program through tool box talk on proper usage of safety helmet also was given followed by an observation to look for the differences before and after the tool box promotion on the use of safety helmet. Result from the descriptive analysis showed high score for knowledge, fair score for the attitude and practice among harvesters. There is no association between knowledge (X2=2.733; p>0.05), attitude (X2=2.546; p>0.05) and practice (X2=2.473; p>0.05) with the head injury. The result also gave no significant differences (p>0.05) of the practices before and after the intervention. However, the trends showed decrease in number of practices after the intervention. This study reveals that the knowledge, attitude and practice are not a prominent indicator for head injury among harvesters

Association of workplace stressors with salivary alpha-amylase activity levels among fresh fruit bunch cutters in Selangor

Background: A cross sectional study was conducted to determine the association between occupational stress risk factors and salivary alpha-amylase activity levels among fresh fruit bunch (ffb) cutters at oil palm plantation. Methods: A total of 109 ffb cutters were selected from two oil palm plantations in Pulau Carey, Selangor at west coast of Malaysia in 2015. Questionnaires were used to determine socio-demographics and occupation information, distress level were determined by using translated 12-items-General Health Questionnaire (GHQ). Kestrel Heat Stress Tracker 4400 was used to measure wet bulb globe temperature (WBGT) for heat stress exposure. Posture analysis was examined based on Rapid Upper Limb Assessment (RULA) method in evaluating working posture and Borg CR-10 scale was rated by ffb cutters to determine exerted force during harvesting process. Stress response system was determined by measuring salivary alpha-amylase (sAA) activity by using sAA kinetic enzyme assay kit (Salimetrics). Results: 35.8% of ffb cutter had high score indicating psychological distress. 49.5% of the cutters had high heat stress exposure. 91.8% used force exertion of 50%MVC and above to cut fresh fruit bunches and 62.4% were classified in Action Level 4 under RULA. 77.0% of the ffb cutters showed high levels of sAA activity after cutting fresh fruit bunches. Conclusion: Workplace stressors such as working environment and ergonomics risk factors play a role to develop stress at workplace among ffb cutters. Therefore, stress preventive measures are needed to reduce the stressors at workplace

Epidemiological, clinical and laboratory peculiarities of mumps in adolescents and adults

Catedra Boli Infecţioase, Tropicale şi Parazitologie Medicală USMF „N.Testemiţanu”, USMF „N.Testemiţanu”, SCBI „T.Ciorbă”The epidemiological, clinical and laboratory peculiarities of mumps in 247 adolescents and adults during the outbreak of 2007-2008 in Republic of Moldova Was investigated. In these patients mumps developed as a severe disease with high incidence of pancreatitis, orchitis and CNS involvement. Pancreatitis and meningitis have not always manifested the classical clinical signs of organ involvement. The effectiveness of one-dose vaccinations in mumps is not sufficient to provide the population protection. Au fost investigate particularităţile epidemiologice, clinice şi de laborator ale oreionului la 247 adolescenţi şi adulţi în perioada epidemiei din anii 2007-2008 în Republica Moldova. La aceşti pacienţi oreionul a evoluat sever cu un procent înalt de pancreatită, orhită şi implicarea SNC. Pancreatita şi meningita nu întotdeauna au evoluat cu manifestări clinice clasice de implicare organică. Vaccinarea cu o singură doză este ineficace pentru a crea o protecţie populaţională

Development of new hard hat dimensions using user-centered design approach among oil palm harvesters

Background: Hard hats are among the personal protective equipment (PPE) used in many industries to reduce the impact of any falling object on the skull and also to prevent head and brain injuries. However, the practice of wearing a safety helmet during working hours is still low. This is due to the physical discomfort perceived by safety helmet users. Objective: Given the unpopularity of the current hard hat, the general perception of workers concerning its use and its measurements are the determining factors in the development of a new hard hat. Method: A cross-sectional study was conducted in which 132 male oil palm harvesters between 19 and 60 years of age were selected from among the employees of the same oil palm harvesting company. A set of questionnaires was developed to collect their socio-demographic information as well as their perceptions of comfort and the prevalence of head injury. In addition, a set of measuring instruments, including Martin’s anthropometry set, was used for head measurement and data collection in respect of the current hard hat. In this research, six respondents were randomly selected to attend an interview session for qualitative assessment. Results: Based on the questionnaires, the unpopularity in the use of the hard hat was largely influenced by factors related to poor design, in general, and, specifically, poor ventilation (64%), load (67%), and physical discomfort (42%). The measurements of the anthropometric parameters and the dimensions of the hard hat also showed a significant mismatch. Conclusion: The unpopularity of the current hard hat among oil palm harvesters stemmed from the discomfort from wearing, which showed that the development of a new hard hat could lead to better usage and the greater likelihood of wearing a hard hat throughout the working day

Magnetic Particle-Based Hybrid Platforms for Bioanalytical Sensors

Biomagnetic nano and microparticles platforms have attracted considerable interest in the field of biological sensors due to their interesting physico-chemical properties, high specific surface area, good mechanical stability and opportunities for generating magneto-switchable devices. This review discusses recent advances in the development and characterization of active biomagnetic nanoassemblies, their interaction with biological molecules and their use in bioanalytical sensors