Herschelobservations of the W3 GMC (II): clues to the formation of clusters of high-mass stars

The W3 giant molecular cloud is a prime target for investigating the formation of high-mass stars and clusters. This second study of W3 within the HOBYS Key Program provides a comparative analysis of subfields within W3 to further constrain the processes leading to the observed structures and stellar population. Probability density functions (PDFs) and cumulative mass distributions (CMDs) were created from dust column density maps, quantified as extinction AV. The shape of the PDF, typically represented with a lognormal function at low Av “breaking” to a power-law tail at high Av, is influenced by various processes including turbulence and selfgravity. The breaks can also be identified, often more readily, in the CMDs. The PDF break from lognormal (Av(SF)» 6–10 mag) appears to shift to higher Av by stellar feedback, so that high-mass star-forming regions tend to have higher PDF breaks. A second break at Av> 50 mag traces structures formed or influenced by a dynamic process. Because such a process has been suggested to drive high-mass star formation in W3, this second break might then identify regions with potential for hosting high-mass stars/clusters. Stellar feedback appears to be a major mechanism driving the local evolution and state of regions within W3. A high initial star formation efficiency in a dense medium could result in a self-enhancing process, leading to more compression and favorable star formation conditions (e.g., colliding flows), a richer stellar content, and massive stars. This scenario would be compatible with the “convergent constructive feedback” model introduced in our previous Herschel study

ДОСЛІДЖЕННЯ ЕНЕРГОНАВАНТАЖЕНОСТІ ФРИКЦІЙНОГО ЗЧЕПЛЕННЯ КОЛІСНИХ МАШИН

A mathematical model of slippage is developed of clutch. Investigations of energy loading of the friction clutch of an armored wheeled vehicle were conducted and the degree of influence of the main design and operational factors on the energy loading of the clutch.Розроблено математичну модель буксування зчеплення. Проведено дослідження енергонавантаженості фрикційного зчеплення броньованої колісної машини та визначено ступінь впливу основних конструктивних і експлуатаційних факторів на енергонавантаженість зчеплення

Crystal ChemistryAnalysis of Ternary Phases in Systems Me-P-S(Se), where Ме – Ag, Cu, Zn, Cd, In, Tl, Sn, Pb

Crystal structures ofternary thio(seleno)hypodiphosphates of metals of groups I-IV of the periodic system were analyzed. Chemical bonds in investigated phases were descripted on the base of interatomic distances in binary and ternary compounds. Key words: ternary compounds, crystal chemistry parameters, structural characteristics.</span

Modified Qigong Breathing Exercise for Reducing the Sense of Hunger on an Empty Stomach

Background: The aims of this study were to determine whether a modified Qigong breathing exercise can reduce the sense of hunger and identify possible mechanisms. Methods: The results from the test group, which performed the exercise, are compared with the control group, which performed deep breathing. Intestinal pressure measurements, stomach pH monitoring, and participant surveys were used for assessment. Results: Stomach pH was increased by 3 (0.2) and intestinal pressure was reduced by 12 (0.5) mm Hg in the experimental group and did not change significantly in the control group. The study provides strong evidence that the exercise can significantly reduce, or even suppress the sense of hunger on an empty stomach. Conclusion: This breathing exercise provides comfort in different circumstances, such as lack of regular meals, limited volume or caloric diet, and even during temporary complete absence of food in therapeutic fasting

Comparative analysis of properties of wires from alloys of Al-REM system, obtained using the methods of continuous extrusion

The article presents the results of experimental studies of the production technology of electrical wire made of aluminum alloy of the Al–REM system with content of rare earth metals in the range of 7-9% using continuous casting and extrusion processing methods. Continuous casting rods with a diameter of 12 mm, obtained by casting into an electromagnetic mold (EMM), were the starting material for research. Methods of continuous extrusion "Conform" and combined rolling-extrusion (CRE) were the main methods to obtain a billet for subsequent drawing. Deformation modes, methods of experiments and equipment for the implementation of two variants of the proposed technology using various methods of continuous extrusion described. At all stages of the technology, samples were taken and the mechanical and electrophysical properties of the obtained deformed semi-finished products (ultimate tensile strength, elongation to failure and electrical resistivity) were studied. Application of the "Conform" method in industrial conditions using standard drawing routes allows obtaining a wire of small diameters with high strength properties, however, the plastic properties and values of electrical resistance do not correspond to the existing requirements of the technical specifications for its production. On the contrary, the plastic properties of hot-extruded rods obtained by the CRE method allow cold deformation using only one intermediate annealing. At the same time, the developed technology using continuous casting, combined rolling-extrusion, drawing modes and final annealing of a wire with a diameter of 0.5 mm provides the required level of plastic and strength properties, as well as minimum values of electrical resistance. The developed modes of deformation and heat treatment can be recommended for the industrial production of electrotechnical wire from high-alloyed Al–REM alloys

Application of Multivariate Statistical Delineation of Prospective Geochemical Providenskaya Area (Chukotka, Russia)

The secondary geochemical field structure was modelled on the basis of the lithogeochemical dispersion trains of the Providenskaya Area of the Chukotka Peninsula. The factor and cluster analysis were applied to interpret the nature of geochemical anomalies. It was proved that a range of anomalies were prospective for gold-silver, polymetallic, tin, and tungsten deposit allocation

Comparative analysis of properties of wires from alloys of Al-REM system, obtained using the methods of continuous extrusion

The article presents the results of experimental studies of the production technology of electrical wire made of aluminum alloy of the Al–REM system with content of rare earth metals in the range of 7-9% using continuous casting and extrusion processing methods. Continuous casting rods with a diameter of 12 mm, obtained by casting into an electromagnetic mold (EMM), were the starting material for research. Methods of continuous extrusion "Conform" and combined rolling-extrusion (CRE) were the main methods to obtain a billet for subsequent drawing. Deformation modes, methods of experiments and equipment for the implementation of two variants of the proposed technology using various methods of continuous extrusion described. At all stages of the technology, samples were taken and the mechanical and electrophysical properties of the obtained deformed semi-finished products (ultimate tensile strength, elongation to failure and electrical resistivity) were studied. Application of the "Conform" method in industrial conditions using standard drawing routes allows obtaining a wire of small diameters with high strength properties, however, the plastic properties and values of electrical resistance do not correspond to the existing requirements of the technical specifications for its production. On the contrary, the plastic properties of hot-extruded rods obtained by the CRE method allow cold deformation using only one intermediate annealing. At the same time, the developed technology using continuous casting, combined rolling-extrusion, drawing modes and final annealing of a wire with a diameter of 0.5 mm provides the required level of plastic and strength properties, as well as minimum values of electrical resistance. The developed modes of deformation and heat treatment can be recommended for the industrial production of electrotechnical wire from high-alloyed Al–REM alloys

Modified Qigong Breathing Exercise for Reducing the Sense of Hunger on an Empty Stomach

Background: The aims of this study were to determine whether a modified Qigong breathing exercise can reduce the sense of hunger and identify possible mechanisms. Methods: The results from the test group, which performed the exercise, are compared with the control group, which performed deep breathing. Intestinal pressure measurements, stomach pH monitoring, and participant surveys were used for assessment. Results: Stomach pH was increased by 3 (0.2) and intestinal pressure was reduced by 12 (0.5) mm Hg in the experimental group and did not change significantly in the control group. The study provides strong evidence that the exercise can significantly reduce, or even suppress the sense of hunger on an empty stomach. Conclusion: This breathing exercise provides comfort in different circumstances, such as lack of regular meals, limited volume or caloric diet, and even during temporary complete absence of food in therapeutic fasting

Computer simulation, analy-sis of force and temperature-speed parameters of the pro-cess of combined machining of Al-Mg-Sc alloys

The results of studies of the combined processing of alloys of the Al-Mg-Sc system with known rheological properties under various temperature-rate and deformation conditions are presented. A computer model of the combined machining process was created and the DEFORM 3D complex was used to analyze the metal flow, the distribution of the strain rate and the temperature of the metal over the cross section of the workpiece when receiving round bars of various diameters. The results of the research were used to develop the production technology of welding wire from alloys of the Al-Mg-Sc system