E conomists have long puzzled over the astounding differences in productivity between fi rms and countries. For example, looking at disaggregated data on U.S. manufacturing industries, Syverson (2004a) found that plants at the 90 percentile produced four times as much as the plant in the 10 percentile on a per-employee basis. Only half of this difference in labor productivity could be accounted...

Experiences in the past decade provide guidance in selecting priorities for investigation of health hazards in chemical industries. Pride of place should be given to the experience of large industrial populations, in part simply because large numbers of people are at risk and in part because such studies are more likely to give reliable answers. This recommendation has further strength when the...

The concept of Occupational Health and Safety Management (OHSM) involves the identification of hazards and risks in the workplace and the definition of the rights, roles and responsibilities of stakeholders in the implementation of control and or preventive measures. The study identifies 5 different classes of hazards to include – chemical, biological, physical, ergonomic and psychosocial hazar...

Applications of mica-based pearlescent pigments are related to plastics, cosmetics, automobiles coatings among others, but they seem to be not explored by the ceramic industry. In this work, intensively red and gold colored muscovite pigments covered with layer of nanoparticles containing iron and zirconium oxides were prepared by homogeneous precipitation. The final color was obtained after th...

Each year over 140 million tons of petroleum-based polymers are produced worldwide and used in the production of such plasticsaspolyethylene, polystyrene, polyvinyl chloride, polyurethane, and others. Mostly using oil, coal, and natural gas as raw materials for their manufacturing, these plastics are common in every facet of our lives from the pharmaceutical industry to household use. Approxima...