Transformations of porous layers upon high-temperature annealing: Simulation

In this work, the lattice kinetic Monte Carlo model has been used to investigate morphological transformations in porous films of different density in the process of high-temperature annealing. The characteristics of porous films of different initial densities have been compared at different time moments of the sintering process. Layers with a porosity from 20% to 50% having a cubic lattice have been studied. It is shown that closed pores are formed in the film if the porosity is less than 25%; in films with a larger porosity, percolation pores arise. It has been established that the rate of sintering depends on the annealing time nonmonotonically.     

Decisions and justifications by community mental health providers about hypothetical ethical dilemmas

OBJECTIVE: Community-based treatment of persons with serious mental illness requires providers to become involved in clients' personal lives to a greater degree than does hospital-based treatment. The study examined attendant ethical dilemmas, especially for staff who lack professional training or work in rural communities. METHODS: A total of 95 staff members from five community mental health centers read 14 vignettes describing ambiguous ethical dilemmas involving professional role boundaries or client confidentiality. Twenty-seven staff members were from rural agencies, and 68 from urban-suburban agencies; 60 were direct care staff, and 35 were supervisory. Participants were asked to make and justify a more conservative or a less conservative decision in response to each dilemma. RESULTS: Years of experience as a mental health provider and previous ethics training correlated positively with staff having experienced more situations similar to those in the vignettes; however, these variables were not related to the decision made or the type of ethical justification for it. When the analysis controlled for experience and previous ethics training, staff made fewer conservative decisions in boundary dilemmas than in confidentiality dilemmas. Compared with nonrural providers, rural providers had experienced more boundary dilemmas and made fewer conservative decisions in response to them. CONCLUSIONS: Boundary problems occur frequently in community-based services, especially in rural settings, and may or may not be handled conservatively. With the expansion of case management and other in vivo services, better understanding of ethical risks and informal practices will help improve services and provide appropriate training and supervision of staff.     

Comparative spontaneous Raman spectroscopy of crystals for Raman lasers

A comparison of the spectroscopic parameters of Raman-active vibronic modes in various crystalline materials with a view to the use of these crystals for stimulated Raman scattering (SRS) is presented. It includes data on the Raman frequency shift, linewidth, integral, and peak Raman scattering cross sections. For steady-state SRS the highest Raman gain coefficient has been proved to be in barium nitrate and sodium nitrate crystals; for transient SRS it is expected to be in lithium niobate and tungstate crystals. Barium tungstate and strontium tungstate are proposed as new highly efficient Raman materials for both SRS cases.     

Influence of the metal atom nature on the efficiency of ethylbenzene oxidation inhibition by Copper(II), Cobalt(III), and Lead(II) <Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>-diethyldithiocarbamates mixed with amines

The joint inhibiting effect of heavy metal N,N-diethyldithiocarbamates M(dtc) _n , where M = Cu(II), Co(III), or Pb(II), and three aromatic amines (1: 1) in the initiated oxidation of ethylbenzene with oxygen at 75°C has been examined. The synergistic inhibitory effect of 1: 1 M(dtc) _n -amine pairs strongly depends on the nature of the metal atom and the chelate unit structure of the metal dithiocarbamate. For most couples, the formation of new Cu(II), Co(III), and Pb(II) complexes of the [M(dtc) _n -amine] type in chloroform via coordination of the amine donor atom to the metal has been proved spectrophotometrically. Possible routes of oxidation chain termination by the newly formed complexes have been established.     

Capture of Nitrogen Oxides with a Fibre Chemisorbent

A system for cleaning nitrogen oxides from a gas-air mixture was proposed. The degree of sorption of nitrogen dioxide is determined by the rate of passage of the gas–air mixture through the filter and its concentration. Weakly basic VION AN-1 fibre treated with 3% sodium hydroxide solution was used as the chemisorbent. A hypothesis was advanced concerning the chemistry of capture of nitrogen dioxide by weakly basic VION AN-1 fibre treated with 3% sodium hydroxide solution.     

Aspects of Synthesis of Decorite Opacified Glass

The paper presents data of the effect of the granular composition, the specific surface area of added metal powders, the batch preparation procedures, as well as the time/temperature conditions of synthesis, the type of the gas medium in the furnace, and the content interval and ratio of metallic additives on the color tone and the opacifying properties of glass melt produced.