A capillary tube is widely used as an expansion device for small refrigeration cycles. Recently, immiscible oil is sometimes used in the refrigeration cycle to improve severe lubricating conditions and to prevent blockage of the capillary tube caused by the hydrolysis of ester oil. This paper discusses the influence of mixing of the immiscible oil with the refrigerant on the flow characteristic...

—A new species of Conopora is described from off Queensland, Australia, the first known unattached stylasterid. It always occurs in a symbiotic relationship with a polynoid polychaete, which determines the colony morphology. Conopora adeta is also the first deep-water stylasterid reported from off Australia (398 m) and the ninth record of a stylasterid from the Australian region. Of the approxi...

1 MRC Vitamin Study Research Group. Prevention of neural tube defects: results of the MRC vitamin study. Lancet 1991;338:132–7. 2 Little J, Elwood M. Geographic variation. In: Elwood JM, Little J, Elwood JH, eds. The epidemiology and control of neural tube defects. Oxford: Oxford University Press, 1992:96–145. 3 Rogers SC, Weatherall JAC. Anencephalus, spina bifida and congenital hydrocephalus....

The paper deals with a detailed analysis of published analytical relations for heat transfer during steam condensation in vertical tube. historical development the approaches and chronological used are presented. Attention is focused on description processes at gas phase-condensate film interface as well inclusion influence presence non-condensable gases. 12 modifications compared each other sa...

We assess dose and image quality of a state-of-the-art angiographic C-arm system (Axiom Artis dTA, Siemens Medical Solutions, Forchheim, Germany) for three-dimensional neuro-imaging at various dose levels and tube voltages and an associated measurement method. Unlike conventional CT, the beam length covers the entire phantom, hence, the concept of computed tomography dose index (CTDI) is not th...

Abstract In this study, based on the energy balance for different components of a double-layered vacuum-tube solar collector with U-tube, thermal performance unit is investigated separately using an analytical and quasi-dynamic method. The model used in study determines temperature distribution longitudinal radial directions. research, effects physical parameters heat transfer including size co...

Field Ion Microscopy (FIM) and Scanning Tunneling Microscopy (STM) have found a wide application in nanotechnology. These microscopes use a metallic nanotip for image acquisition. Resolution of FIM and STM images depends largely on the radius of nanotip apex; the smaller the radius the higher the resolution. In this research, for tungsten nanotip fabrication, electrochemical etching of tungsten...

B2223 High Temperature Superconductor (HTSC) has been prepared as a pellet by solid state reaction. Then, HTSC wires were fabricated from the prepared superconductor using powder in tube (PIT) method utilizing silver as the tube material. Superconductor powder was packed in the pure silver tube of about 4.5 mm diameter, and 50mm long. The prepared wires are of three types; with monofilament MOF...

helical coil heat exchangers are widely used in industrial applications ranging fromcryogenic processes, air-conditioning, and nuclear reactors to waste heat recovery due totheir compact size and high heat transfer coefficient. in this kind of heat exchangers, flowand heat transfer are complicated. this paper reports a numerical investigation of theinfluence of different parameters such as coil...

The deformation of armchair single-walled carbon nanotube under transverse electric field has been investigated using density functional theory. The results show that the circular cross-sections of the nanotubes are deformed to elliptic ones, in which the tube diameter along the field direction is increased, whereas the diameter perpendicular to the field direction is reduced. The electronic st...