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[en] Highlights: • A new smart U-shaped TENG based on liquid-solid contact electrification is proposed. • The complicated mechanical motions can be transmitted into liquid pressure and electricity signal by U-shaped TENG. • The U-shaped TENG can be working as smart multifunctional sensors to detect the displacement, pressure, torsion, and so on. A new smart U-shaped triboelectric nanogenerator (TENG) was reported basing on solid-liquid contact triboelectrification and the Pascal's law, in which the complicated mechanical motions can be transmitted into liquid pressure and electricity signal. The U-shaped TENG driven by inertial force and air flow is designed as an energy harvesting device to collect the mechanical energy with a stable peak output voltage and current of about 20 V and 400 nA, respectively. The relationship between the output performance and the water sliding conditions is investigated in detail with a stable peak output performance at the point of resonance. The U-shaped TENG can also be working as smart multifunctional sensors to detect the displacement, pressure, torsion, and so on. As a self-powered displacement sensor, the U-shaped TENG shows a high sensitivity of 0.91 V mm−1 and 8.50 nA mm−1. As a pressure sensor, it also exhibits a high sensitivity of 4.41 V kPa−1 and 72.94 nA kPa−1, respectively. This work expands the practical applications of the solid-liquid triboelectrification based TENGs for energy harvesting and smart sensors in wide fields with advantages of simple fabrication, low cost, portable and self-powered properties.
[en] Background. To date, bronchial diverticula have generally been treated as a pathological condition associated with chronic obstructive pulmonary disease (COPD), although only a limited amount of published information is available on the relationship between bronchial diverticula as depicted by multidetector computed tomography (MDCT) and airflow limitations. Purpose. To evaluate the relationship between airflow limitations and main bronchial diverticula in the subcarinal region using spirometry and thin-section MDCT. Material and Methods. A total of 189 consecutive adult patients were retrospectively evaluated based on spirometry and thin-section MDCT of the chest. All examinations were performed at our institution between June and October 2008. The study group included 70 women and 119 men with a mean age of 65 years (range 19-86 years). The relationship between the FEV1% and bronchial diverticula in the subcarinal region was analyzed (Student's t-test). Results. The indications for conducting the examinations were pulmonary diseases (82 patients), cardiovascular diseases (22), extrapulmonary malignancies (74), and other conditions (11). A total of 84/189 (44.4%) patients showed bronchial diverticula, and the FEV1% of 70/84 (83.3%) patients was above 70. The FEV1% of patients with lesions ranged from 26.0 to 97.8 (mean 76.8), whereas the range was 28.1-94.4 (mean 73.7) in those without lesions. There was no significant association between the FEV1% and the presence of subcarinal bronchial diverticula (P > 0.05). Conclusion. Our data demonstrate that thin-section chest CT commonly demonstrates main bronchial diverticula in the subcarinal region in patients without airflow limitations. We propose that the presence of a small number of tiny bronchial diverticula under the carina may not be a criterion for the diagnosis of COPD
[en] This paper reports the design, fabrication, and testing of a centimeter-scale (Ørotor=35mm), 250°C-compliant microturbine for aeronautic applications. Dedicated to low-speed air flows (≈3 m/s and down to 2 m/s), this device is the first flow-driven harvester withstanding such high temperatures and high vibration levels (107 cycles at 20G). Furthermore, the proposed harvester exhibits the highest output power per unit cross sectional area compared to prior art in the cm-scale and low velocity ranges. (paper)
[en] To maintain the optimum condition of Advanced Fuel Science Building in KAERI, this report is described leak tests for HEPA Filter of HVAC in this facility. The main topics of this report are as follows for: - Procurement Specification - Visual Inspection - Airflow Capacity Test - HEPA Filter Bank In-Place Test
[en] The present study provides some experimental observations on the structural developments of bubbly flow and the void wave damping in vertical, circular channel with a large diameter, and discusses the channel size effect on them. It is observed that the developing mode of bubbly flow structures and its transition mechanism are influenced by the channel size as well as the bubble size, and that they are well revealed in the behavior of wave damping
[en] Plasma Technology is a well-known approach to decontaminated not only pesticide residues but also fungus on fruits and vegetables. In the present paper, Non-Thermal Plasma (NTP) were successful generated via plasma activated water technique, pin hole. NTP were applied to decontaminated pesticide residues named, cypermethrin, on “Sai Num Pueng”, tangerine fruit. A electrical power 125 watt and air flow rate 15L/min has been used. It was observed that cypermethrin concentration is significantly reduce from 1 ppm to 0.25 ppm which meet international food standard requirment (Codex standard). In particular, the NTP tangerine orange exhibits longer shelf-life as compared to the conventional tangerine orange. There are no significantly different related to appearance, acid flavor, sweetness and smell as also compared to conventional products. (paper)
[en] The scheme of an experiment and certain results of the interaction of a free air vortex tube with a surface are considered. A solution of a differential equation for a plane cross section of a quasisolid tubular vortex core whose density varies according to a polytrope law is analyzed
[en] The multi-nozzle electrospinning is under extensive investigations because it is an easy way to enhance the productivity and also feasible to produce special structure fibers such as core-shell fibers and to fabricate composite fibers of those polymers that cannot form blend solution in common solvent. Control over the multi-nozzle electrospinning fibers deposition has attracted increasing attentions. The most common method was to use the auxiliary electrode. However, the concentrated effect of the works of control multi-nozzle electrospinning deposit was inconspicuous. To enhance the controlling of multi-nozzle electrospinning deposition, a set-up based oppositely charged electrospinning was designed. In this set-up the air flow was used to transport neutralized nanofibers. This electrospinning method was named oppositely charged and air auxiliary electrospinning (OCAAES). The capacity of OCAAES in deposition area and pattern controlling were investigated. By the OCAAES, concentrated and several patterned nanofibers deposition were fabricated. Results showed that nanofiber deposition area and pattern of multi-nozzle electrospinning could be controlled actively, and nanofiber deposition could be fabricated in a quick thickening rate.
[en] Analysis of a great number of works allows concluding that many types of GTE and GTU nozzles can be divided into 3 main groups and 3 intermediate (composite) groups. The developed general classification of atomizers with descriptions of their operating principles, advantages and disadvantages is used to select a type of device for development. The most promising type chosen from descriptions given in the paper is the one with atomization of fuel by high-speed air flow. (paper)
[en] To investigate the flooding phenomenon in nearly horizontal pipes the experimental studies are performed in the facility with the length of 2160mm, with three different inner diameters of 40mm, 60mm, and 70mm, and with the various inclination angles. Air and water approximately at room temperature and at atmospheric pressure are used as test fluids. The local void factions are measured by the three conductance probes located at the inlet, middle, and exit of water flow, respectively. Two mechanisms governing the transition to flooding are proposed. The effects of pipe end geometry, pipe diameter, and inclination angle are investigated and the comparisons with the slug formation models are conducted. It is found in this study that the transition to flooding is originated from two mechanisms i.e. 'wave instability' and 'high head flooding', and two regions (sub-critical and super-critical) coexist if the air flow increases up to a criticalvalue. It is observed that large roll waves are grown to the critical amplitude in the sub-critical region, does not show any dustive growth phenomenon. When the void fraction in the sub-critical region is used as the parameter for the flooding criterion, Ishii's slug formation model predicts the data without systematid errors. On the other hand, when the voide fraction in the super-critical region is selected as the parameter, Taitel's slug formation model best fitsthe data. Data obtained in the condition of high head flooding are not in good agreement with the results predicted by the slug formation models. Also, the transition criterion to the onset of flooding is very sensitive to the inclination angle, and the effect of pipe end geometry on the onset of flooding is negligible