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[en] This invention relates to pressure vessel penetrations and, more particularly, to feedwater inlet conduit and steam discharge nozzle apparatus for nuclear reactor systems, and the like. (author)

[en] In this rectangular shutter, which can contain a vacuum, the pre-shutter and the shutter plates are cooled. The circular case for holding the shutter part of the heavy ion accelerator has a circular intermediate flange ring in its centre as a hub, which is fixed by fins to the case. The fins and intermediate flange ring are made hollow, where the hollow spaces are connected together and have cooling water flowing through them. (DG)

[en] In differential pumping, the pumping speed has in the past been controlled by the size of the orifice between the vacuum chamber and the diffusion pump. This fixed orifice is usually in the valve gate of a high-vacuum valve (or in a baffle plate). To change the pumping speed, then, the valve must be removed and another valve with an orifice of a different size must be inserted. This process is time consuming and risks contamination of the system, which would require another pumpdown and bakeout. A simple shutter that controls pumping speed without requiring any change in components has been developed. The shutter consists of 20 leaves arranged as an iris that opens to a 6-in.-dia orifice or closes to 0.25 in. The shutter consists of a mounting ring, the leaves, a drive ring, and a drive gear. Each leaf is stainless steel with a pivot pin at one end and an offset pin at the other. The leaves are placed in the mounting ring and the drive ring and the drive gear are attached. Rotating the drive gear moves the leaves and changes the orifice size. One of the shutters has been used successfully with a 4-in. diffusion pump system. In this system the pressure is 100 μ in the vacuum chamber and 0.0001 μ at the diffusion pump. The shutter was placed above the cold trap so it could be used for both diffusion pumping and roughing

[en] Cu–Ni–Sn alloys are well known for their excellent properties, including excellent elasticity and high strength, which enable large potentials for applications in microelectronic industry and 3D printing for example. Preparation of the high quality spherical powders should meet the new requirements in these emerging fields. In this work, the mono-sized Cu-13Ni-17Sn (wt%) microspheres with controllable diameters ranging from 84.4 μm to 212.0 μm were prepared by pulsated orifice ejection method (POEM). Solidified Cu–Ni–Sn microspheres exhibit good sphericity and remarkably narrowed size distribution. The percentage of microspheres with sphericity of more than 0.9 is high up to 98.6%, and the average sphericity of microspheres is 0.989. The surface of Cu–Ni–Sn microspheres is smooth, and the interior contains no pores and impurities. Furthermore, the cooling rate of Cu-13Ni-17Sn microspheres was estimated in a Newton’s cooling model. With decreasing particle diameter, the cooling rate of Cu-13Ni-17Sn microspheres increases gradually. When the particle diameter is less than 84.4 μm, the cooling rate of microspheres exceeds 3.64 × 10⁴ K s⁻¹. With increasing particle size, the secondary dendrite arm spacing increases gradually owing to the decrease of the sphere cooling rate. (paper)

[en] A low pressure evaporation fresh water generation system is designed for converting brackish water or seawater into fresh water by distillation in low pressure and temperature. Distillation through evaporation of feed water and subsequent vapor condensation as evaporation produced fresh water were studied; tap water was employed as feed water. The system uses the ejector as a vacuum creator of the evaporator, which is one of the most important parts in the distillation process. Hence liquid can be evaporated at a lower temperature than at normal or atmospheric conditions. Various operating conditions, i.e. temperature of feed water and different orifice diameters, were applied in the experiment to investigate the characteristics of the system. It was found that these parameters have a significant effect on the performance of fresh water generation systems with low pressure evaporation

[en] This study compared the area of the regurgitant orifice, as measured by the use of multidetector-row CT (MDCT), with the severity of aortic regurgitation (AR) as determined by the use of echocardiography for AR. In this study, 45 AR patients underwent electrocardiography- gated 40-slice or 64-slice MDCT and transthoracic or transesophageal echocardiography. We reconstructed CT data sets during mid-systolic to enddiastolic phases in 10% steps (20% and 35-95% of the R-R interval), planimetrically measuring the abnormally opened aortic valve area during diastole on CT reformatted images and comparing the area of the aortic regurgitant orifice (ARO) so measured with the severity of AR, as determined by echocardiography. In the 14 patients found to have mild AR, the ARO area was 0.18± 0.13 cm² (range, 0.04-0.54 cm²). In the 15 moderate AR patients, the ARO area was 0.36 ± 0.23 cm² (range, 0.09-0.81 cm²). In the 16 severe AR patients, the ARO area was 1.00 ± 0.51 cm² (range, 0.23-1.84 cm²). Receiver-operator characteristic curve analysis determined a sensitivity of 85% and a specificity of 82%, for a cutoff of 0.47 cm², to distinguish severe AR from less than severe AR with the use of CT (area under the curve = 0.91; 95% confidence interval, 0.84-1.00; p < 0.001). Planimetric measurement of the ARO area using MDCT is useful for the quantitative evaluation of the severity of aortic regurgitation

[en] Purpose. To classify the anatomic types of the right internal spermatic vein (ISV). Methods. We evaluated venograms obtained in 150 consecutive patients with idiopathic varicocele referred for transfemoral sclerotherapy .Results. Six anatomic types of the right internal spermatic vein (ISV) were recognized. These were classified by the location of their orifices and the tributary venous patterns. In roughly half the patients (53%), the ISV appeared as a simple vein with no remarkable retroperitoneal interconnections. In the remainder, complex retroperitoneal anastomoses were encountered. Conclusion. By understanding these anatomic variations, the angiographer can approach treatment of right-sided varicocele with foreknowledge of the nature of these types and the presence of valves and collaterals

[en] Highlights: • The influence of elliptical orifices on the inner nozzle flow is compared. • Five nozzles with different elliptical and circular orifices are simulated. • Differences in the flow coefficients and cavitation morphology are observed. • Horizontal axis orifices are ease to cavitate, with a higher discharge coefficient. • A better mixing process quality is expected for the horizontal major axis nozzles. - Abstract: In this paper a computational study was carried out in order to investigate the influence of the use of elliptical orifices on the inner nozzle flow and cavitation development. With this aim, a large number of injection conditions have been simulated and analysed for 5 different nozzles: four nozzles with different elliptical orifices and one standard nozzle with circular orifices. The four elliptical nozzles differ from each other in the orientation of the major axis (vertical or horizontal) and in the eccentricity value, but keeping the same outlet section in all cases. The comparison has been made in terms of mass flow, momentum flux and other important non-dimensional parameters which help to describe the behaviour of the inner nozzle flow: discharge coefficient (C_d), area coefficient (C_a) and velocity coefficient (C_v). The simulations have been done with a code able to simulate the flow under either cavitating or non-cavitating conditions. This code has been previously validated using experimental measurements over the standard nozzle with circular orifices. The main results of the investigation have shown how the different geometries modify the critical cavitation conditions as well as the discharge coefficient and the effective velocity. In particular, elliptical geometries with vertically oriented major axis are less prone to cavitate and have a lower discharge coefficient, whereas elliptical geometries with horizontally oriented major axis are more prone to cavitate and show a higher discharge coefficient

[en] Multi-hole orifice(MO) as a new type of throttling element is designed, and the characteristics of the discharge coefficient, the head loss and anti-swirl performance are experimentally studied. Compared with that of the standard orifice, the discharge coefficient of MO is more stable, and less sensitive to the upstream swirl, and the head loss is close to that of the standard orifice. For the three pairs plate of equivalent β of 0.42, 0.59, and 0.65, the variation of the MO's discharge coefficient is lower than that of the standard orifice by 0.83%, 2.02% and 1.67%, respectively. The MO performance is superior to the standard orifice in anti-swirl aspect for lower β(β=0.42), while the situation becomes opposite for larger β(β=0.65). (authors)