Synthesis of glycolide by depolimerization of glycolic acid oligomers modified by polyhydric alcohols

Oligomers of glycolic acid esterified by ethylene glycol, propylene glycol, glycerin were obtained. These samples were depolymerized with various oxide catalysts such as MgO, ZnO, SnO[2] and Sb[2]O[3]. The resulting glycolide was analyzed by gas chromatography in different eluents - acetonitrile and hexafluoroisopropanol. It was shown that modification of glycolic acid oligomers by polyhydric alcohols reduces the content of hydroxyl containing impurities in raw glycolide

Dynamics of tidal synchronization and orbit circularization of celestial bodies

PACS number s : 05.45.Xt, 05.45.Gg, 95.10.Ce, 96.15.DeWe take a dynamical-systems approach to study the qualitative dynamical aspects of the tidal locking of the rotation of secondary celestial bodies with their orbital motion around the primary. We introduce a minimal model including the essential features of gravitationally induced elastic deformation and tidal dissipation that demonstrates the details of the energy transfer between the orbital and rotovibrational degrees of freedom. Despite its simplicity, our model can account for both synchronization into the 1:1 spin-orbit resonance and the circularization of the orbit as the only true asymptotic attractors, together with the existence of relatively long-lived metastable orbits with the secondary in p:q synchronous rotationWe acknowledge projects OTKA T72037 Hungary , Hielocris Spain , the Human Frontier Science Program I.T. , MCI project CGL-2008-06245-C02-02 Spain , and the Spanish-Hungarian Binational project TeT ESP-34/2006.Peer reviewe

Fire risk assessment of a health care facility

Статья посвящена расчету величины индивидуального пожарного риска на объекте защиты санаторий-профилакторий ТПУ. Производился анализ причин пожаров в учреждениях здравоохранения, а также расчет индивидуального пожарного риска на объекте защиты санаторий-профилакторий ТПУ и сопоставление расчетных величин с нормативным значением пожарного риска. Приведены мероприятия по снижению вероятности возникновения пожара и повышению проводимых работ по техническому обслуживанию и планово-предупредительному ремонту систем противопожарной защиты АПС, СОУЭ в санатории-профилактории ТПУ.The article is devoted to calculating the value of individual fire risk at the object of protection of the sanatorium-preventorium of TPU. The analysis of the causes of fires in health care institutions, as well as the calculation of individual fire risk at the object of protection of the sanatorium-preventorium of TPU and comparison of the calculated values with the standard value of fire risk. Measures are given to reduce the probability of fire and increase the ongoing maintenance and scheduled preventive repair of fire protection systems APS, SSE in the sanatorium-preventorium of TPU

Clean and efficient extraction of copper ions and deposition as metal

AbstractA simple, clean and efficient one-pot process is offered as an alternative to the conventional complex processing presently used to extract copper ions from copper containing materials, like copper concentrate or slag, and to form copper metal. The alternative process uses a eutectic molten salt of potassium chloride, sodium chloride and zinc chloride as the reaction fluid which is recyclable, low in cost, environmentally benign, low melting (melting point 204°), high boiling (vapor pressure is only a few psi at 800°) and chemically, thermally and physically stable. The metal completely dissolves out of copper concentrate or slag in the aerobic eutectic molten chloride salt in a graphite or glassy carbon pot, which serves as a cathode, with a graphite anode, to reduce the metal ions to metal which sinks to the bottom of the graphite pot. The total efficiency for extraction and deposition is virtually 100% as determined by elemental and gravimetric analyses

Does a 4 diagram manual enable laypersons to operate the laryngeal mask supreme®? A pilot study in the manikin

<p>Abstract</p> <p>Background</p> <p>Bystander resuscitation plays an important role in lifesaving cardiopulmonary resuscitation (CPR). A significant reduction in the "no-flow-time", quantitatively better chest compressions and an improved quality of ventilation can be demonstrated during CPR using supraglottic airway devices (SADs). Previous studies have demonstrated the ability of inexperienced persons to operate SADs after brief instruction. The aim of this pilot study was to determine whether an instruction manual consisting of four diagrams enables laypersons to operate a Laryngeal Mask Supreme^®(LMAS) in the manikin.</p> <p>Methods</p> <p>An instruction manual of four illustrations with speech bubbles displaying the correct use of the LMAS was designed. Laypersons were handed a bag containing a LMAS, a bag mask valve device (BMV), a syringe prefilled with air and the instruction sheet, and were asked to perform and ventilate the manikin as displayed. Time to ventilation was recorded and degree of success evaluated.</p> <p>Results</p> <p>A total of 150 laypersons took part. Overall 145 participants (96.7%) inserted the LMAS in the manikin in the right direction. The device was inserted inverted or twisted in 13 (8.7%) attempts. Eight (5.3%) individuals recognized this and corrected the position. Within the first 2 minutes 119 (79.3%) applicants were able to insert the LMAS and provide tidal volumes greater than 150 ml (estimated dead space). Time to insertion and first ventilation was 83.2 ± 29 s. No significant difference related to previous BLS training (P = 0.85), technical education (P = 0.07) or gender could be demonstrated (P = 0.25).</p> <p>Conclusion</p> <p>In manikin laypersons could insert LMAS in the correct direction after onsite instruction by a simple manual with a high success rate. This indicates some basic procedural understanding and intellectual transfer in principle. Operating errors (n = 91) were frequently not recognized and corrected (n = 77). Improvements in labeling and the quality of instructional photographs may reduce individual error and may optimize understanding.</p

Dispersal within a spatially structured population of lesser kestrels: The role of spatial isolation and conspecific attraction

1. Factors governing dispersal rates have seldom been examined in spatially structured populations of vertebrates. We gathered information during 8 years on transfer rates between subpopulations in a spatially structured, growing population of colonial lesser kestrels Falco naumanni, and analysed the contribution of several variables related to spatial isolation and characteristics of both subpopulation of origin and destination on probabilities of dispersal. 2. Lesser kestrels were highly philopatric to their subpopulations, but first-breeders dispersed more often than adults (26% vs. 4%, n = 1706) because adults were reluctant to move from familiar areas. Frequency of subpopulation change was higher in females than in males (first-recruiters: 30% vs. 22%, n = 987; adults 5% vs. 1%, n = 719), according to their different breeding roles. However, all populational factors had an equal effect on individuals of different sex and dispersal status. 3. Movement rates decreased with inter-subpopulation distance - indicating that travelling to distant subpopulations may impose costs in terms of breeding prospects -and with the number of subpopulations, which increased during our study period. 4. Conspecific attraction strongly influenced the probability of dispersal: it was relatively higher in largely populated subpopulations, and individuals of large subpopulations were reluctant to change to others. These results were neither influenced by the size and breeding density of the subpopulations nor by habitat quality in terms of food availability or risk of predation, as indicated by breeding success of kestrels at each subpopulation. The number of conspecifics could be used by the kestrels as a cue of patch quality in terms of settlement options, and large subpopulations could be more easily detected by prospecting birds. 5. Our study highlights the fact that several assumptions of theoretical metapopulation modelling are often not fulfilled in nature. Both theoretical models and management strategies on spatially structured populations or metapopulations should thus consider the number, population size, and spatial distribution of local populations, as well as their relationships with the dispersal ability of the species.Peer Reviewe