scholarly journals Experimental Data of the Ear Threshing Process in a Pneumatic Device

2020 ◽  
Vol 30 (1) ◽  
pp. 111-132
Author(s):  
Viktor I. Pakhomov ◽  
Sergey V. Braginets ◽  
Oleg N. Bakhchevnikov ◽  
Elena V. Benova ◽  
Artem I. Rukhlyada
Keyword(s):  
Current Problem ◽  
Rotor Blades ◽  
Reduced Pressure ◽  
Light Load ◽  
Pneumatic Device ◽  
Cereal Grain ◽  
Grain Damage ◽  
Experimental Apparatus ◽  
Motion Speed ◽  
High Level

Introduction. The current problem is the high level of grain injuries during the threshing process. Therefore it is necessary to develop the gentle methods for separating grains from ears. These methods shall exclude direct shock influence of operative parts of the threshing devices on cereal grains. The objective of research is to study the process of the wheatear threshing in the pneumatic device and to estimate the influence of device settings on cereal grain separation and damage. Materials and Methods. The experimental apparatus is a pneumatic threshing device. The threshing is carried out in case of the interaction of an ear and concave under the influence of the alternating high and low pressure of the airflow generating by the rotor’s blades. Separation is carried out by means of deriving light-load tailings into the reduced pressure chamber. Results. The grain damage decreases in reducing the speed of rotor blades motion and consequently the speed of ears motion in the threshing unit. Germ damage and grain breakage decrease almost to zero at a minimum blade motion speed of 13.5 mps. The range of blade speed between 13.5 and 20 mps is the most favorable for the pneumatic grain threshing in terms of the germ damage. The pneumatic threshing on the experimental device results in effective assorting of grains and light-load tailings of ears. Discussion and Conclusion. Process of the wheat ears pneumatic threshing has satisfactory results. The pneumatic threshing reduces grain endosperm damage by 10…12%. Grain germ damage decreases by 5%, practically to zero. Crushing of grain at rotor blades minimum speed is no more than 0.5%. Comparison of shares of the damaged and crushed grains when using the pneumatic threshing with shares of the damaged grains when using the traditional combine threshing has showed that the offered method of the threshing provides a reduction in grain damage.

Improvement of Stalling Characteristics of an Axial-Flow Fan by Radial-Vaned Air-Separators

2010 ◽  
Vol 132 (2) ◽  
Author(s):  
Nobuyuki Yamaguchi ◽  
Masayuki Ogata ◽  
Yohei Kato
Keyword(s):  
Solid Wall ◽  
Axial Flow ◽  
Internal Flow ◽  
Rotor Blades ◽  
Relative Location ◽  
Flow Conditions ◽  
Axial Flow Fan ◽  
Light Load ◽  
Stall Prevention ◽  
Air Separator

An improved construction of air-separator device, which has radial-vanes embedded within its inlet circumferential opening with their leading-edges facing the moving tips of the fan rotor-blades so as to scoop the tip flow, was investigated with respect to the stall-prevention effect on a low-speed, single-stage, lightly loaded, axial-flow fan. Stall-prevention effects by the separator layout, relative location of the separator to the rotor-blades, and widths of the openings of the air-separator inlet and exit were parametrically surveyed. As far as the particular fan is concerned, the device together with the best relative location has proved to be able to eliminate effectively the stall zone having existed in the original solid-wall characteristics, which has confirmed the promising potential of the device. Guidelines were obtained from the data for optimizing relative locations of the device to the rotor-blades, maximizing the stall-prevention effect of the device, and minimizing the axial size of the device for a required stall-prevention effect, at least for the particular fan and possibly for fans of similar light-load fans. The data suggest the changing internal flow conditions affected by the device conditions.

Canister Sealing for High Level Waste Encapsulation

2001 ◽  
Author(s):  
Richard E. Andrews
Keyword(s):  
Electron Beam Welding ◽  
Deep Level ◽  
High Level Waste ◽  
Spent Fuel ◽  
Reduced Pressure ◽  
Friction Stir ◽  
The Uk ◽  
High Level ◽  
Welding Processes ◽  
And Storage

Abstract Sweden has chosen to manage spent fuel rods by direct encapsulation and storage in a deep level repository. Two welding processes are being investigated for the sealing of copper vessels that form the outer barrier of the disposal canisters. TWI Ltd in the UK has developed Reduced Pressure Electron Beam Welding and Friction Stir Welding for 50mm thick copper. This paper describes some of the investigations and compares the techniques. Over the past 3 years a full-size canister welding machine has been designed and built. Specialised tools have been developed for the welding of thick sections in copper with very encouraging results.

Synthesis of soft N-donor isoPentyl-BTBP and study on its removal of actinides from high level liquid waste

2020 ◽  
Vol 108 (6) ◽  
pp. 425-431
Author(s):  
Shunyan Ning ◽  
Jie Zhou ◽  
Shichang Zhang ◽  
Wei Zhang ◽  
Yuezhou Wei
Keyword(s):  
Adsorption Kinetics ◽  
Contact Time ◽  
Porous Silica ◽  
Liquid Waste ◽  
Polymer Support ◽  
High Level Liquid Waste ◽  
Reduced Pressure ◽  
The Stability ◽  
High Level ◽  
Excellent Stability

AbstractTo directly separate actinides from high level liquid waste (HLLW), a novel molecule, i. e. isoPentyl-BTBP (6,6′-bis(5,6-bis(4-methylpentyl)-1,2,4-triazin-3-yl)-2,2′-bipyridines) was synthesized and characterized. A kind of isoPentyl-BTBP/SiO2-P adsorbent was obtained by impregnating isoPentyl-BTBP into porous silica/polymer support particles SiO2-P under reduced pressure. The effect of HNO3 concentration, contact time on the adsorption of isoPentyl-BTBP/SiO2-P towards 241Am(III) and 239Pu(IV) was studied. And the stability of isoPentyl-BTBP/SiO2-P in HNO3 medium was also evaluated. It turned out that isoPentyl-BTBP/SiO2-P had much higher affinity for 241Am(III) and 239Pu(IV) over FP elements in 3 M HNO3, fast adsorption kinetics towards 239Pu(IV), excellent stability in HNO3 medium, and should be a very promising adsorbent for separating 239Pu(IV) and 241Am(III) from HLLW.

Proposal of a New Ultrasonic Welding Technique for Thermoplastic Polymer

2009 ◽  
Vol 83-86 ◽  
pp. 1129-1134 ◽  
Author(s):  
Yong Bo Wu ◽  
Takashi Sato ◽  
Jian Hui Qiu ◽  
Wei Min Lin
Keyword(s):  
Tensile Strength ◽  
Ultrasonic Vibration ◽  
Normal Pressure ◽  
Ultrasonic Welding ◽  
Frictional Heat ◽  
Experimental Apparatus ◽  
High Level ◽  
Plastic Parts ◽  
Welding Pressure ◽  
Welding Technique

This paper proposes an alternative ultrasonic welding technique capable of welding plastic parts with different shapes and sizes. In this method, a thin plastic sheet of less than 0.5 mm in thickness is fixed to the ultrasonic vibration body called the horn, and two plastic workpieces to be welded are pressed upon the sheet from both sides at a constant normal pressure. Once the horn starts to ultrasonically vibrate, frictional heat is momentarily generated between the sheet and the plastic workpieces, increasing the frictional temperature to a high level. When the temperature increases to over the melting point of all the materials, the materials melt and eventually are welded after the ultrasonic vibration stops. In the current work, an experimental apparatus was designed and constructed. A series of experiments was subsequently carried out on the apparatus to investigate how the surface roughness of the workpieces, the welding time, and the normal welding pressure affect the actual welding area and the tensile strength of the welded workpieces. The experimental results showed that a bigger welding area and a higher tensile strength can be obtained under the appropriate welding conditions, providing validation of the new welding method.

Removal and Containment of High-Level Radioactive Polonium From Liquid Lead-Bismuth Coolant

1997 ◽  
Vol 506 ◽  
Author(s):  
E.I. Yefimov ◽  
D.V. Pankratov ◽  
S.V. Ignatiev
Keyword(s):  
High Energy ◽  
Liquid Lead ◽  
Alkaline Extraction ◽  
Vacuum Sublimation ◽  
Safety Standards ◽  
Experimental Apparatus ◽  
The Us ◽  
High Level ◽  
Secondary Neutrons ◽  
Spallation Product

ABSTRACTThe channels of polonium nuclide formation in lead-bismuth target irradiated by high energy protons and secondary neutrons are considered. Under off blanket condition the activity of 200po -210Po, as well as the fission and spallation product activity are calculated for 15 MW target after 1 year operation. Polonium separation methods, including removal using alkaline extraction, vacuum sublimation, and so-called carrier method are analyzed. The engineering design for experimental apparatus to test polonium removal and containment using alkaline extraction using tellurium as a chemical analog of polonium is developed. The necessary degree of polonium removal to keep concentration below levels appropriate to meet the US and Russia safety standards is estimated. Comparative analysis of alkaline extraction and vacuum sublimation techniques from the viewpoint to achieve the necessary removal depth is carried out.

Measurements of Secondary Flows and Turbulence in a Turbine Cascade Passage

1987 ◽  
Author(s):  
Pietro Zunino ◽  
Marina Ubaldi ◽  
Antonio Satta
Keyword(s):  
Kinetic Energy ◽  
Turbulent Kinetic Energy ◽  
Turbine Rotor ◽  
Secondary Flows ◽  
Rotor Blades ◽  
Turbulent Shear ◽  
Pressure Probe ◽  
Shear Stresses ◽  
Passage Vortex ◽  
High Level

The results of an experimental investigation on secondary flows in a linear cascade of turbine rotor blades are presented. To gain information on the turbulence related to the secondary flow development in turbine cascades, measurements have been carried out at eight normal sections in the passage and at a plane downstream of the trailing edge, using a constant temperature hot wire anemometer and a total pressure probe. A high level of turbulent kinetic energy and turbulent shear stresses has been found to be associated with the passage vortex. This result confirms that secondary loss generation in cascades is related to the production of turbulent kinetic energy in the vortex flow and to its viscous dissipation.

scholarly journals Protection of organic cereals from insect and rodent pests in a warehouse by combined use of traps and sticky tapes

2021 ◽  
Vol 36 (2) ◽  
pp. 61-72
Author(s):  
Petar Kljajic ◽  
Goran Andric ◽  
Goran Jokic ◽  
Marijana Prazic-Golic ◽  
Tanja Blazic ◽  
...  
Keyword(s):  
Spring Wheat ◽  
Insect Pests ◽  
Test Period ◽  
Control Effect ◽  
Combined Application ◽  
Combined Use ◽  
Grain Moisture ◽  
Cereal Grain ◽  
Grain Damage ◽  
Sticky Tape

Several options of protection of organic cereals (winter and spring wheat, rye and maize) from insect and rodent pests, using a combination of traps (with or without pheromone/ attractant) and sticky tapes and no chemicals, were tested in a warehouse over the summerspring season of 2019/2020. Temperature in the warehouse was 14-29?C and humidity around 50%. The average grain moisture of winter and spring wheat and rye was 10-11%, while it was 12-14% in maize grain, and the average grain temperature of all cereals was 13-27?C. Regarding stored-product insect pests, five coleopteran, two moth and one Psocoptera species were detected, and the coleopterans predominated (98.5%) along with secondary pest insects (94.0%). Regarding rodents, only specimens of Mus musculus were found throughout the test period, their maximum monthly frequency being 72 (in January 2020). A combination of traps (with or without pheromones) and sticky tape barriers was found to provide an effective tool for trapping insects. Also, snap traps and trapping boxes for killing rodents, when used simultaneously with sticky tape barriers, were found to provide good protection of cereals from house mice. The pest control effect was also confirmed by collecting samples of organic cereal grain, which showed no significant presence of stored-product insects or grain damage (0.94% and 0.96% in spring wheat and rye, respectively) at the end of the test period. The results showed a great potential of combined application of traps and sticky tapes for protecting organic cereals in horizontal bulk storages, but the use of chemicals approved for organic food production would be required under extended storage periods.

scholarly journals Benefits of haemoglobin in the cladoceran crustaceanDaphnia magna

2001 ◽  
Vol 204 (20) ◽  
pp. 3425-3441 ◽  
Author(s):  
R. Pirow ◽  
C. Bäumer ◽  
R. J. Paul
Keyword(s):  
Muscle Tissue ◽  
Oxygen Supply ◽  
Hypoxia Tolerance ◽  
Limb Muscle ◽  
Ambient Oxygen ◽  
Nadh Fluorescence ◽  
Experimental Apparatus ◽  
Beating Rate ◽  
High Level

SUMMARYTo determine the contribution of haemoglobin (Hb) to the hypoxia-tolerance of Daphnia magna, we exposed Hb-poor and Hb-rich individuals (2.4–2.8 mm long) to a stepwise decrease in ambient oxygen partial pressure (PO2amb) over a period of 51 min from normoxia (20.56 kPa) to anoxia (<0.27 kPa) and looked for differences in their physiological performance. The haem-based concentrations of Hb in the haemolymph were 49 μmol l–1 in Hb-poor and 337 μmol l–1 in Hb-rich animals, respectively. The experimental apparatus made simultaneous measurement of appendage beating rate (fa), NADH fluorescence intensity (INADH) of the appendage muscles, heart rate (fh) and in vivo Hb oxygen-saturation possible. In response to progressive, moderate hypoxia, both groups showed pronounced tachycardia and a slight decrease in fa. The fa and fh of Hb-rich animals were generally 4–6 % lower than those of Hb-poor animals. In addition, Hb-rich animals showed a significant decrease in the PO2amb at which the Hb in the heart region was half-saturated and a striking reduction in the critical PO2amb of appendage-related variables. In Hb-poor animals, the INADH signal indicated that the oxygen supply to the limb muscle tissue started to become impeded at a critical PO2amb of 4.75 kPa, although the high level of fa was largely maintained until 1.77 kPa. The obvious discrepancy between these two critical PO2amb values suggested an anaerobic supplementation of energy provision in the range 4.75–1.77 kPa. The fact that INADH of Hb-rich animals did not rise until PO2amb fell below 1.32 kPa strongly suggests that the extra Hb available to Hb-rich animals ensured an adequate oxygen supply to the limb muscle tissue in the PO2amb range 4.75–1.32 kPa. This finding illustrates the physiological benefit of Hb in enabling the animal to sustain its aerobic metabolism as the energetically most efficient mode of fuel utilization under conditions of reduced oxygen availability.

Continuous recordings of brain regional circulation during sleep/wake state transitions in rats

1996 ◽  
Vol 270 (4) ◽  
pp. R855-R863 ◽  
Author(s):  
D. Gerashchenko ◽  
H. Matsumura
Keyword(s):  
Slow Wave Sleep ◽  
Regional Blood Flow ◽  
Paradoxical Sleep ◽  
State Transitions ◽  
Small Vessels ◽  
Regional Circulation ◽  
Experimental Apparatus ◽  
Large Brain ◽  
Freely Behaving ◽  
High Level

Continuous measurement of regional blood flow (RBF) in the brain of a freely behaving rat was attained by a combination of laser-Doppler (LD) flowmetry and our originally devised apparatus, which had been developed for the automatic releasing of the twisting of lines connected between experimental apparatus and the freely behaving animal. RBF changes were studied in a ventral region of the rostral basal forebrain along with sleep-wake states. When compared with the RBF level during slow-wave sleep (SWS), levels of RBF during paradoxical sleep (PS) and wakefulness were higher by 24 (P = 0.0001) and 9% (P < 0.05), respectively. The LD signals suggested that the RBF elevation during PS was produced by dilation of both the large brain arteries and small vessels, whereas the elevation during wakefulness was caused by dilation of small vessels that was counteracted by contraction of large arteries. It was noticed that the original circulation tended to begin changing before the onset of SWS. A circadian rhythm was also demonstrated for the RBF, which largely decreased around the onset of the light period and returned to the high level before the beginning of the dark period. Thus continuous and real-time recordings of regional circulation were performed with satisfactorily precision in freely behaving rats.

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