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The boiling heat-transfer performances of R1234ze(E)/R152a (0.4/0.6 by mass) flowing inside a horizontal micro-fin tube of 9.52 mm outer diameter were researched by experiment. Under the experiment...

The condensation heat transfer characteristics of a new environmental refrigerant mixture R1234ze (E)/R152a (mass ratio 40:60, named NCUR01) in a horizontal micro-fin tube with an outer diameter of...

Although microfin tubes are widely used in refrigeration and air-conditioning industries, relatively little data are available for small diameter tubes. In the present study, 7.0 and 5.0 mm outer d...

In the present study, two titanium corrugated tubes (22.2 mm outer diameter and 0.5 mm tube thickness) having widely different corrugation pitch (2.1 and 22.1 mm) and having the same corrugation de...

Thermal performance of pulsating heat pipes (PHPs) is dependent to several factors. Inner and outer diameter of tube, filling ratio, thermal conductivity, heat input, inclination angle, and length of each section are the most influential factors in the design process of PHPs. Since water is a conventional working fluid for PHPs, thermal resistance and effective thermal conductivity of PHPs filled with water are modeled by applying a GMDH (group method of data handling) neural network. The input data of the GMDH model are collected from other experimental investigations to predict the physical properties including thermal resistance and effective thermal conductivity of PHPs filled with water as working fluid. The accuracy of the introduced models are examined through the R2 tests and resulted in 0.9779 and 0.9906 for thermal resistance and effective thermal conductivity, respectively.

Mihori Kita, Yukiko Fujii, Sachiyo Hama Department of Ophthalmology, National Organization Kyoto Medical Center, Kyoto, Japan Abstract: Drying of the cornea during surgery, which causes poor visibility of the fundus, is one of the most serious problems when using a noncontact-type wide-angle viewing system. This study used a newly commercialized lens for observing the fundus with a noncontact wide-angle viewing system. The lens used has a very thin meniscus made of polymethyl methacrylate and a large outer diameter. Following the application of viscoelastic material, the lens can be put on the cornea without using a contact lens fixation ring. The larger diameter and lightweight characteristics of the new lens contributed to the overall stabilization. The smooth surface of this lens was able to achieve an intraoperative view of good quality not only during vitrectomy but also during scleral buckling procedures. Keywords: contact lens, observing fundus, vitrectomy, scleral buckling, noncontact wide-angle viewing system

A new opposed-anvil high pressure and temperature apparatus was developed based on the Drickamer-type apparatus. Various improvements were made to increase the sample volume and to generate high pressure and temperature stably and easily. By optimizing components such as the anvil, heater, and gasket, large sample volumes of about 4 mm3 (∼103 times more than that previously obtained with our previous apparatus) were achieved, with compact and light apparatus (outer diameter ϕ 40 mm; height 31 mm; weight 300 g). Pressures and temperatures up to about 15 GPa and 1700 K can routinely and stably be achieved by using this assembly. In order to extend the pressure range further, sintered diamond was used as an anvil material. As a result, pressures and temperatures of around 38 GPa and 1400 K were achieved, although the sample volume was decreased to about 1.3×10−1 mm3.

In this study, a gas-in-oil compound-drop stream was produced by the breaking up of an oil jet with gas core, and its burning characteristics were observed. The compound jet broke up into stable compound drops if the spacing between bubbles was greater than the circumference of the compound jet. The outer diameter of the compound drops was about 1.8 times of the inner diameter of the outer tube and the ratios of inner to outer diameters of the compound drop depended only on the gas-to-liquid velocity ratios. After entering a high-temperature environment, the gas-in-oil compound drop exploded shortly due to the rupture of the oil shell. The gas core was released immediately and formed a microfuel jet. The burning of a gas-in-oil compound drop could be separated into two stages: explosion of the compound drop and burning of the remaining single-phase drop. The explosion intensity is relatively weaker compared with the microexplosion of an emulsion drop or a liquid-in-liquid compound drop.

LiCoO2 xerogel hollow nanofibers were first prepared by co‐electrospinning the sol precursor, and the polycrystalline LiCoO2 hollow nanofibers were obtained after calcination of the xerogel fibers. The obtained hollow nanofibers made up of 20∼30 nm nanocrystals were about 100 nm to several micrometers in outer diameter. The hollow nanofibers were detected by means of SEM, TEM, TG, DSC, FTIR, and XRD techniques.

Understanding the effects of forming history on the subsequent hydroformability of aluminum alloy tubes is critical for widespread acceptance of aluminum as a light-weight alternative in automotive components. The aim of this research is to investigate the influence of pre-bending on the characteristics of aluminum alloy tubes for the hydroforming process. Tube bending experiments were performed on 2 and 3.5 mm wall thicknesses with 76.2 mm outer diameter EN-AW5018 tube. In the tube bending experiments, key process parameters such as boost were varied and the effect on the resultant thinning, strains and springback of the as-bent tubes was assessed. Bending boost is shown to reduce thinning and strains in the as-bent tubes which has been found to be favourable for any subsequent hydroforming operation.

The carpal organ is a glandular complex implicated in scent communication. To investigate its ethological significance, morpho‐functional evaluations were conducted on 67 glands collected from animals of different ages and sex during the 2002 hunting season (October–December) in the Bergamo district, Northern Italy. All samples were histologically and morphometrically examined to determine gland surface and thickness, number of secretory tubules per area and outer diameter of the tubules. Comparative analyses revealed significant differences in the above parameters between sub‐adults and adults for both sexes, but no differences were found between adult males and females. However, when all specimens were pooled, males revealed more developed and functional glands than females, with the oldest males having the highest values of gland surface, gland thickness and tubule diameter. Our findings suggest that this organ plays a relevant role in social communication by producing chemical signals involved in terr...

The structure of type I and type II modifications of Al–Co–Ni decagonal quasicrystals was studied by using the high-angle annular detector dark-field scanning transmission electron microscopy (HAADF-STEM) technique. It was found that the quasi-unit-cell should be selected as columnar decagon of 3.2 nm in diameter and 0.82 nm in height, and its center consists of a bright circle with 0.76 nm of the outer diameter, indicating that atomic distribution in the quasi-unit-cell is disordered. Lattices obtained by connecting the centers of the atom clusters in HAADF images reveal that the lattice of the type I modification is rhombic Penrose tiling and the lattice of the type II is a mixture of the rhombic and pentagonal tilings. Namely, the lattice of the type II modification is a mixture of the lattices of the type I and S1 modifications.

The aim of this work was to study the process of capsules coating in a lab-scale spouted bed. A conventional spouted bed (CSB) with 9.5 cm column diameter and 60° conical base was used in the experiments. The spouting fluid dynamics of capsules with different sizes were determined. In the equipment used only capsules size 03 (outer diameter: 5.82 cm; length: 15.9 mm) presented stable spouting. The effect of capsules load in the column, coating suspension viscosity, and coating time on the coating efficiency were studied in a factorial experimental design. Typical efficiencies for the process were found to be in the range of 69.54–84.88%. The efficiencies increased with bed load at 1% significance level, but were not affected by coating time and suspension viscosity. CBS is a promising method for the HGC coating that eliminates preliminary sealing steps.

This paper reports the influence of the spiral angle on the heat transfer performance during condensation inside spiraled micro-fin tubes having constant geometric parameters such as fin height, pitch, shape (apex angle), and fin number, as various papers previously published in this field had not clearly established this influence. Tests were conducted for condensation of R-22, R-134a, and R-407C inside a smooth tube (9.52 mm outer diameter) and three micro-fin tubes with approximately the same diameter and spiral angles of 10°, 18°, and 37°, respectively. Experimental results indicated a heat transfer augmentation with spiral angle increase. A new semi-empirical predictive correlation was developed for the practical design of spiraled micro-fin tubes. The proposed new correlation predicted the majority of experimental results of the present study within a deviation zone of ±20 percent.

In 2004, the officially announced Japanese standard for the evaluation of car–front safety performance in terms of pedestrian child head protection required a 3.5 kg headform impactor as a test tool simulating a child pedestrian head. Currently, ACEA–TNO have jointly developed a 3.5 kg headform impactor in Europe. The primary aim of the present study is to investigate the availability of the 3.5 kg ACEA–TNO headform impactor in terms of the Japanese standard. Meanwhile, JAMA–JARI have together developed a 3.5 kg headform impactor in Japan. The secondary aim of our study is to present the physical characteristics and measured head injury criteria (HIC) of the JAMA–JARI and ACEA–TNO headform impactors obtained here as a point of reference for the formulation of the Global Technical Regulation (GTR) standards now under way. The technical specifications regarding mass, outer diameter, moment of inertia, location of centre of gravity, seismic mass location of accelerometers, natural frequency, and bio...

A major advantage of compliant air-lubricated bearings is their excellent performance at very high rotational speeds and operating temperatures. Successful development of these bearings requires experimental testing of new bearing designs under equally extreme conditions. Traditionally, high-speed thrust bearing test rigs have utilized rotors supported on precision ball bearings, and were unable to fully cover the operating speed and temperature range of the tested air-lubricated bearing. This paper describes the design and performance of two new-generation thrust bearing test rigs, which are completely oil-free, and can operate at significantly extended range of speed and temperature. The new test rigs were designed for thrust bearings up to 0.012 m (4 in) outer diameter, operating speeds up to 80,000 rpm, and temperatures up to 650 °C (1200 °F). Over 350 tests performed to date have demonstrated successful rig operation at thrust loads up to 1330 N(300 lbs), speeds up to 80, 000 rpm, and temperature ran...

This paper deals with the stress analysis and strength evaluation of bonded shrink fitted joints subjected to torsion. The stress distributions in the adhesive layer of bonded shrink fitted joints are analyzed by the axisymmetric theory of elasticity when an external torsion is applied to the upper end of the shaft. The effects of the outer diameter and the stiffness of rings on the interface stress distributions are clarified by numerical calculations. Using the interface stress distributions, the joint strength is predicted. In addition, the joint strength was measured experimentally. It is seen that rupture of the adhesive layer is initiated from the upper edge of the interface when torsion is applied to the upper end of the shaft. The numerical results are in fairly good agreement with the experimental results. It was found that the joint strength of bonded shrink fitted joints is greater than that of shrink fitted joints.

A flexible videoscope with an outer diameter of 3.8 mm and equipped with a movable tip was used for in situ observation of roots growing in larger‐sized biopores. We were able to display root morphology and position inside of biopores and differentiate four categories of root segments.

We use the ultrasonic surgical system in the treatment of brain tumors such as meningioma, neurinoma, glioma, etc. SONOPET is a useful and safe ultrasonic surgical system for microsurgery. The outer diameter of the tip of ultrasonic surgical systems is usually 2.5 mm and the inner diameter 2.0 mm. However, the outer diameter of the SONOPET is 1.9 mm and the inner diameter 1.5 mm. Even in a deep site, because of the small diameter tip, the operation can be done easily. Further, the very thin outer diameter of the tip flue, 5 mm, makes it easy to operate in the deep site. The maximum amplitude of the distal end tip, which can be an important factor in tissue fragmentation, is 240 microns. It is said that the thinner tip breaks down easily, but by reducing metal fatigue the lifetime of the tip is longer and a larger amplitude can be obtained. As a result, hard tissue fragmentation becomes available even with a thinner tip. The handpiece is very light in weight, approximately 110 g, helping to reduce operator fatigue when in long term use. The weight is approximately one-half of conventional types. Because of the high efficiency of the electricity/vibration energy conversion rate, the handpiece does not heat up during the operation. Also, since water cooling is not necessary, the procedures before and after use are simple. Changing the handpiece during the operation is also easy.

Tests were run to compare the fatigue life of two-row tapered roller bearings to that of spherical roller bearings. Both bearing types had an outer diameter of 110 mm with the spherical roller bearing having a 22 percent larger dynamic radial load rating than the tapered roller bearings. All tests were run at 165 percent of the respective two-row dynamic radial load ratings. The results show that both the indirect mounting (double cup or outer ring) and the direct mounting (double cone or inner ring) tapered roller bearings gave significantly better fatigue lives than the spherical roller bearings. These results appear to contradict the present ISO 281 standard which assigns a 1.15 bm rating factor to spherical roller bearings compared to a bm rating factor of 1.10 for that of tapered roller bearings. Presented at the 53rd Annual Meeting in Detroit, Michigan May 17–21, 1998

The development of front-line endoscopic technology has introduced new opportunities during endoscopic retrograde cholangiopancreatography (ERCP) to single-handedly allow direct inspection of detailed structures of the biliary and even the pancreatic duct. This paper presents a new flexible technology delivered with an outer diameter of 0.9 mm giving an image transmission of 6000 pixels. We report on a case where direct inspection of an alleged duct defect, of potential pathogenetic significance, was considered essential in order to substantiate the subsequent clinical management.

In the present paper technical design details of a non-contact digital laser scanning micrometer based on microprocessor have been given. The system uses a low power He-Ne laser and works well in a hostile environment. The instrument can measure outer diameter, internal diameter, thickness and other multidimensions of different type of objects. Besides, it works well for in sito measurement. An accuracy of better than ten micron has been achieved in the range of 1–35 mm.

SummaryIt is possible to minimise the invasiveness of diagnosis in cases of pathological nipple secretion by examining the lactiferous duct using microfibre optics. In this study, the visualisation of the internal lactiferous duct was tested on an animal model and in humans. Flexible fibre-endoscopes, with diameters of 0.50 and 0.75 mm (3000 and 6000 pixel), and a semi-rigid fibre-endoscope with a diameter of 0.85 mm (6000 pixel) were tested in conjunction with Teflon catheters and rigid steel microtrocars of 0.8, 1.1 and 1.2 mm outer diameter. The lactiferous duct system could be visualised reproducibly from the orificium of the ductus mamillaris over all its ramifications to its endings in complete expansion.

INTRODUCTION A researcher in the Anatomy and Cell Biology Division of our institution, the State University of New York Health Science Center at Brooklyn, was conducting cell growth experiments. These experiments required a regular supply of 1-1/2 inch outer diameter petrie dishes, with a 5/16 inch hole drilled precisely in the center of each dish, to allow cell growth to occur in a concentric ring within the dish. A supply of petrie dishes, and an 8 inch Sears Craftsman drill press, were available to the researcher.

The authors have studied fundamentally and experimentally the explanation of the sealing mechanism of oil seals. It will be generally noticed that the suction of air occurs to the rubbing portion of the lip of an oil seal which is operating under sealing condition. For the purpose of studying sealing characteristics of an oil seal in the authors' investigations, the volume, [Qbar], of transferred lubricating oil instead of air is used as a means of estimating the sealing status. The authors have clarified that there exists the relation, [Qbar]/uD2∞G1/2, wherein G, u and Dare nondimensional parameter of oil seals, sliding velocity of between shaft and seal and shaft outer diameter, respectively, and that suction coefficient of oil, K (=[Qbar]/uD2G1/2), is dependent on the sealing characteristic constant, Φ, the surface roughness and the lip material of seals. In this paper, it becomes clear that there exists the relation, K = Ko + α(Φnor - Φcon), wherein Φcon are the values estimated by f/G1/3 in the case ...

It will be noticed that the suction of air occurs to the rubbing portion of the lip of an oil seal, which is operating under sealing condition. For the purpose of studying sealing phenomena of an oil seal in this paper, the suction volume per an unit time, [Qbar] of lubricating oil instead of air is used as a means of estimating the sealing status. It becomes clear that there is the relation, [Qbar]αG1/2 , wherein G is nondimensional parameter of oil seal, and that suction coefficient of oil, K (=[Qbar]/uD2 G1/2 , wherein u and D are sliding velocity of between shaft and seal and shaft outer diameter, respectively, depends on the sealing characteristic constant, Φ, the surface roughness of the rotating shaft and its eccentricity. Presented as an American Society of Lubrication Engineers paper at the ASLE/ASME Lubrication Conference in Kansas City, Missouri, October 3–5, 1977

Sphincter of Oddi manometry was performed in three anesthetized dogs, using different measuring catheter diameters, ranging from 1.0 to 1.9 mm. No differences were seen either in sphincter of Oddi wave amplitude, frequency, and base-line pressure or in common bile duct pressure measured after cannulation during 20 min with catheters of 1.0 and 1.3 mm. However, significant disturbances of these variables were present when the measuring catheter diameter was 1.6 and 1.9 mm. It is concluded that the diameter of the recording catheter is of crucial importance in sphincter of Oddi manometry. In dogs with a body weight of 30-40 kg, the outer diameter should not exceed 1.3 mm.