background: in this study, the chemical quality of water in some sub-basins of gamasiab river has been investigated for a long term planning of water consuming in the region . methods: the area is about 11 x10 3 km 2 , located in ramadan and kermanshah, the two western regions of iran. in this regard the results of the water samples, which were collected on the outlet of the 13 hydrometrical st...

risk assessment and management techniques are used in industrial activities to reduce accidents by applying preventive and protective methods. in this article a preventive approach called hazard and operability study (hazop) was used. the application of hazop, a process hazard identification and control method, has been demonstrated in the fatty acid unit of golnar oil company, northwest of teh...

In order to investigate effect of application of Nitroxin and nitrogen chemical fertilizer on yield and yield components, split plot experiment on the basis of Randomized Complete Block Design with four replications was conducted. Four levels of Nitrogen fertilizer (N1: 100% chemical fertilizer, N2: 75% chemical fertilizer + 100% biological fertilizer, N3: 50% chemical fertilizer + 100% biologi...

background: the use of chemicals is essential in education resulting in exposure to these pollutant in a variety of chemical and research laboratories. chemical contaminants in chemical laboratories are in different forms and chemical exposure risk assessment is important for choosing appropriate controls in protecting the health of operators, experts and students. for risk assessment in chemic...

When a single object is created from its constituents, a step-bystep assembly strategy is a modus operandi which allows the control of success and sometimes even an error correction after each sequential step. Moreover, it guarantees the uniqueness of the fabricated object. However, the fabrication of several identical objects by assembly or by shaping its constituents is much more effective if...

Molecules that emulate in part the remarkable capabilities of protein motors were recently chemically synthesized. A promising approach is based on physically interlocked macromolecular complexes such as rotaxanes and catenanes. Using the latter, Leigh et al. [Leigh, D. A., Wong, J. K. Y., Dehez, F. & Zerbetto, F. (2003) Nature 424, 174-179] constructed a molecular rotor in which two small ring...

This SafetyNet suggests chemical substitutes for commonly used chemicals to promote a safer work environment. Consider using the safer substitute if it works in your process: Sample of Chemical Substitute List. View full list here [1].

Research in chemical induction [5] seeks to identify the compound or compounds responsible for differentiation [6] in a developing embryo. Soren Lovtrup [7] compared the search for these compounds to the search for the philosopher?s stone. It was based on the assumption that the differentiating agents have to be chemical substances either within cells or in the extracellular matrix. However, de...