Investigation of oxidation process of mechanically activated ultrafine iron powders

The oxidation of mechanically activated ultrafine iron powders was studied using X-ray powder diffraction and thermogravimetric analyzes. The powders with average particles size of 100 nm were made by the electric explosion of wire, and were subjected to mechanical activation in planetary ball mill for 15 and 40 minutes. It was shown that a certain amount of FeO phase is formed during mechanical activation of ultrafine iron powders. According to thermogravimetric analysis, the oxidation process of non-milled ultrafine iron powders is a complex process and occurs in three stages. The preliminary mechanical activation of powders considerably changes the nature of the iron powders oxidation, leads to increasing in the temperature of oxidation onset and shifts the reaction to higher temperatures. For the milled powders, the oxidation is more simple process and occurs in a single step

The Dynamics of Vortex Structures and States of Current in Plasma-Like Fluids and the Electrical Explosion of Conductors: 3. Comparison with Experiment

The present paper is a concluding part of the series [N.B. Volkov and A.M. Iskoldsky: 1; 2; [1], [2]]. Here on the basis of the results of the above papers the experiments on the electric explosion in conductors have been discussed and the mechanism of "hot" plasma spots formation which was repeatedly observed in the experiments on a plasma focus, z-pinches, vacuum sparks and electric explosion of microwires has been proposed. To realize this mechanism, the formation of sausage-type instabilities is not necessary. Moreover, the possibility of hot spots formation in a liquid metal (in the model under discussion, the plasma-like medium is assumed incompressible and the local kinetic transport coefficients - constant) has been shown. The latter is of great interest for understanding the mechanism of initiation and operation of vacuum arc cathode spots and also for the explanation to the phenomenon of explosive electron emission which is widely employed in applied physics.Comment: LaTeX, 10 PostScript figures, (E-mail: [email protected]). Accepted for publication in J.Phys.A: Math. and Gen. (1993-1994

Patient Safety Culture in Health Care Facilities in Ukraine (Message 1)

Using a questionnaire from the United States Agency for Research and Quality in Health Care (AHRQ), the characteristics of patient safety (PS) culture in the staff of various health care facilities (HCF) in Ukraine were analyzed. In addition, the characteristics of PS culture were analyzed depending on the length of service and affiliation of the respondents to the medical or nursing staff, as well as the profile of therapeutic or surgical activities. It is established that the weakness of the PS culture of the staff of domestic HCF is "Reaction to mistakes" (less than 30% of positive responses), which indicates the predominance of culture of accusation (unfair culture) in Ukrainian HCF and as a consequence fears of the staff to disclose mistakes and accordingly, the lack of opportunity to learn from these mistakes.“Staffing” is identified as a weakness of the PS culture (less than 50% of positive responses) in most comparison groups. It is worth noting such a characteristic of the culture of BP, as the "Frequency of error messages" (less than 70% of positive responses). The Cronbach's alpha coefficient in all groups of respondents ranged from 0.62 to 0.78, which indicates the truth of the results of the study

A Comparative Analysis on Safety Culture in Domestic and Foreign Health Care Facilities and Enterprises of Other Activities (Message 2)

The characteristics of the safety culture of patients and personnel in health care facilities in Ukraine as a whole and separately among doctors-pathologists are analyzed with correlation of the data obtained with similar indicators of the culture of patient safety in medical facilities of other countries and comparison with the safety culture of workers of domestic nuclear power plants. It was confirmed that the weaknesses of the safety culture of the personnel of domestic hospitals is characterized by "Reaction to mistakes", which indicates the prevalence of the culture of blame (unfair culture) in domestic hospitals and, as a result, the absence of real data on medical errors and other incidents of patient safety. The high percentage of positive responses to the safety culture characteristic “Response to mistakes” among the workers of Ukrainian nuclear power plants is an example of the possibility of forming an appropriate safety culture in a separate domestic industry, and the high percentage of positive answers by this characteristic in domestic pathologists is a significant potential for the development of a safe hospital environment for patients. in Ukraine