Chemisorption of gases and reaction of propane dehydration at chromic oxide

Characteristics of Cr₂O₃ as an adsorbent and as a catalyst of propane dehydration by carbon dioxide are studied by adsorption and calorimetric techniques and by kinetic techniques, respectively. Carbon dioxide is usually applied as a dehydrating agent for a number of processes in the coal-chemical industry. For the first time, the molar heats of chemisorption of gases at Cr₂O₃ are studied under elevated temperatures. Cr₂O₃ surface is homogeneous relative to its chemisorption ability. Hydrogen is capable of chemisorbing at the surface (the molar heat of chemisorption is equal to 309.4 kJ/mol) and of sorbing into the solid body (the molar heat of sorption is equal to 170.45 kJ/mol), carbon dioxide is capable of chemisorbing at the surface (the molar heat of chemisorption is equal to 103 kJ/mol). The occurrence of hydrogen in the Cr₂O₃ body induces the Cr₂O₃ capability of sorbing an additional oxygen amount over that characteristic for completely oxidized samples that contain no hydrogen. Chemisorption of excessive oxygen proceeds up to the stoichiometry that corresponds to formation of hydroxyls in the Cr₂O₃ body. Hydrogen sorption by chromic oxide influences its catalytic activity.     

New Catalysts of Hydrocarbon Pyrolysis

Lower olefins - ethylene and propylene - occupy a leading position in the feedstock base of domestic and foreign petrochemistry. Thermal pyrolysis of hydrocarbons in tube furnaces, which ensures the almost maximum yield of target products, is the basic production process. This is due to continuous improvement of the basic equipment in the process units. In pyrolysis furnace block structures, it was directed toward making the process conditions more severe to attain the maximum yield of target products.__________Translated from Khimiya i Tekhnologiya Topliv i Masel, No. 2, pp. 41 – 43, March – April, 2005.     

Profiling care and benchmarking best practice in care of hospitalized elderly: the Geriatric Institutional Assessment Profile

This article reports on a new instrument, the Geriatric Institutional Assessment Profile (GIAP), developed to assess (1) hospital workers' knowledge, attitudes, and perceptions regarding care of geriatric patients, and (2) the perceived adequacy of an institutional environment to serve geriatric patients' needs. Findings are reported from 303 questionnaires completed by health care employees from a 658-bed academic medical center. Internal consistency estimates were consistently high for the various components of the GIAP. Factor analysis was performed to examine underlying dimensions of knowledge and institutional environment. The GIAP has the potential to narrow the gap between actual and best practice in geriatric care by identifying staff information needs and concerns, as well as institutional barriers and facilitators to providing quality geriatric hospital care.     

Natural Gas as Motor Fuel

The necessity of developing and using alternative motor fuels, natural gas and products of its processing in particular, is due to two interrelated basic causes: the rapid depletion of oil reserves on the planet and deterioration of the environmental situation in many, primarily developed, countries.__________Translated from Khimiya i Tekhnologiya Topliv i Masel, No. 3, pp. 3 – 8, May – June, 2005.     

Determination of tricyclic antidepressants for ED analysis

Both the Biosite Triage (Biosite Diagnostics, San Diego, CA) method and the Du Pont aca (Du Pont Company, Wilmington, DE) method give qualitative tricyclic antidepressant (TCA) results to aid in the diagnosis of a TCA overdose. The Triage method uses urine samples and the aca uses serum samples. Although the cutoff values vary considerably between the two methods, the Triage results agreed well with the aca results. The Triage test has an advantage in instrument maintenance and time savings, allowing a reduction in turn-around time for our emergency department. Both urine and serum samples were obtained from 44 patients who were admitted to the emergency department with a diagnosis of "possible tricyclic overdose." Discrepancies between the two methods were resolved by thin layer chromatography (Toxi-Lab, Ansys, Inc, Irvine, CA). Both methods were in agreement with the exception of five patients' samples. In this study, the Triage method allowed for detection of TCA using urine that is simple for the user and yielded higher sensitivity and specificity results compared with the Du Pont aca method.     

Adsorption of 2,4-dichlorophenoxyacetic acid on activated carbon

The kinetics of adsorption of 2,4-dichlorophenoxyacetic acid (2,4-D) as a typical herbicide from aqueous solutions on coconut shell activated carbon was studied without preliminary treatment. The surface structure of the activated carbon, which is responsible for its properties, was characterized. The order of reaction in the process of adsorption was determined. The high adsorption capacity of the coconut shell activated carbon was shown.     

Induction of acute phase gene expression by brain irradiation

PURPOSE: To investigate the in vivo acute phase molecular response of the brain to ionizing radiation. METHODS AND MATERIALS: C3Hf/Sed/Kam mice were given midbrain or whole-body irradiation. Cerebral expression of interleukins (IL-1 alpha, IL-1 beta, IL-2, IL-3, IL-4, IL-5, IL-6), interferon (IFN-gamma), tumor necrosis factors (TNF-alpha and TNF-beta), intercellular adhesion molecule-1 (ICAM-1), inducible nitric oxide synthetase (iNOS), von Willebrand factor (vWF), alpha 1-antichymotrypsin (EB22/5.3), and glial fibrillary acidic protein (GFAP) was measured at various times after various radiation doses by ribonuclease (RNase) protection assay. The effects of dexamethasone or pentoxifylline treatment of mice on radiation-induced gene expression were also examined. RESULTS: Levels of TNF-alpha, IL-1 beta, ICAM-1, EB22/5.3 and to a lesser extent IL-1 alpha and GFAP, messenger RNA were increased in the brain after irradiation, whether the dose was delivered to the whole body or only to the midbrain. Responses were radiation dose dependent, but were not found below 7 Gy; the exception being ICAM-1, which was increased by doses as low as 2 Gy. Most responses were rapid, peaking within 4-8 h, but antichymotrypsin and GFAP responses were delayed and still elevated at 24 h, by which time the others had subsided. Pretreatment of mice with dexamethasone or pentoxifylline suppressed radiation-induced gene expression, either partially or completely. Dexamethasone was more inhibitory than pentoxifylline at the doses chosen. CONCLUSIONS: The initial response of the brain to irradiation involves expression of inflammatory gene products, which are probably responsible for clinically observed early symptoms of brain radiotherapy. This mechanism explains the beneficial effects of the clinical use of steroids in such circumstances.     

Ethanol consumption and resistance are inversely related to neuropeptide Y levels

Genetic linkage analysis of rats that were selectively bred for alcohol preference identified a chromosomal region that includes the neuropeptide Y (NPY) gene. Alcohol-preferring rats have lower levels of NPY in several brain regions compared with alcohol-non-preferring rats. We therefore studied alcohol consumption by mice that completely lack NPY as a result of targeted gene disruption. Here we report that NPY-deficient mice show increased consumption, compared with wild-type mice, of solutions containing 6%, 10% and 20% (v/v) ethanol. NPY-deficient mice are also less sensitive to the sedative/hypnotic effects of ethanol, as shown by more rapid recovery from ethanol-induced sleep, even though plasma ethanol concentrations do not differ significantly from those of controls. In contrast, transgenic mice that overexpress a marked NPY gene in neurons that usually express it have a lower preference for ethanol and are more sensitive to the sedative/hypnotic effects of this drug than controls. These data are direct evidence that alcohol consumption and resistance are inversely related to NPY levels in the brain.