Artículos de revistas: "Sieves"

1

Meshram, Himanshu, Nihal Bawankar, Yash Nikhar, Danish Khan, Labhesh Petkar, Mohammad Kaif Abdul Aziz, Ubed Khan y Dr M. Shakebuddin. "Design and Fabrication of Multi-Sieve Sand Sieving Machine". International Journal for Research in Applied Science and Engineering Technology 10, n.º 5 (31 de mayo de 2022): 1606–13. http://dx.doi.org/10.22214/ijraset.2022.42606.

Texto completo

Resumen

Abstract: This paper presents the design and fabrication of a sand sieving machine with multiple sieves that can be changed according to the usage of the work. As we see at every construction site, sand is sieved by old hand-operated (mesh sieving) techniques. Where the siever of a particular size is kept at support from the ground and then sand is poured onto the siever and then manually the sand is sieved by the hand making the sand travel onto the siever and the leftover sediments will be left at one face and the sieved sand will be on another. This technique is time-consuming and for fine sand filtration, it will adequately take a much longer time to sieve. To overcome this problem there are many machines which were designed but only a few of them can be handled at work site. In our design, we use two siever plates which are kept one aside from the other which are hung by the chain of which on end is fixed with the main body. The sievers to which an offset shaft from the motor is attached are to be driven. This offset will create the torsional vibrations with the to and fro motion. This will create the charge particles to get sieved and the leftover charge will move forward and then it will be sieved onto the other siever and the leftover particles will discharge out of the machine. This will reduce the time of sand sieving compared to the hand-operated technique and hence the efficiency and profitability will increase. Keywords: Sand, Sand Sieving Machine, Multi-Sieve, Motor Operated, Two Sieve, Mesh Plate, Screening, Vibrations.

Los estilos APA, Harvard, Vancouver, ISO, etc.

2

Bojic, Nada, Ruzica Nikolic, Branimir Jugovic, Zvonimir Jugovic y Milica Gvozdenovic. "Uniaxial tension of drying sieves". Chemical Industry 67, n.º 4 (2013): 655–62. http://dx.doi.org/10.2298/hemind120824109b.

Texto completo

Resumen

Although the literature contains numerous studies that have been developed to describe the nonlinear behavior of drying sieves' operation, there are no papers in this which report deeper investigation of the drying sieve behavior when exposed to tension and thermo stabilization. The aim of this paper is to provide insight into the elastoplastic behavior of the thermo stabilized and not stabilized sieves subjected to the tensile force. Within this work both theoretical and experimental investigations were performed. The sieves were joined by using a spiral. In separate experiments tests of wire base and weft of the weave mesh were performed, both for thermo stabilized and not thermo stabilized sieves, sieves joining and the sieve thermo stabilization itself. It was established that the thermo stabilization of sieves provides for stability of sieves' dimensions and that open thermo stabilized drying sieve exhibits better mechanical properties and exploitation characteristics then the sieves joining.

Los estilos APA, Harvard, Vancouver, ISO, etc.

3

Rusten, B. y H. Ødegaard. "Evaluation and testing of fine mesh sieve technologies for primary treatment of municipal wastewater". Water Science and Technology 54, n.º 10 (1 de noviembre de 2006): 31–38. http://dx.doi.org/10.2166/wst.2006.710.

Texto completo

Resumen

Fine mesh sieve technologies were tested in full scale at several municipal wastewater treatment plants. A screening test was used to characterize wastewater and establish the design criteria for the sieves. To achieve high removal efficiencies it was crucial to operate the sieves with a filter mat. Rotating belt sieves performed best in the full-scale tests. A small dose of cationic polymer and a static flocculator ahead of a rotating belt sieve achieved excellent results on a wastewater that was originally found unsuitable for primary treatment with fine mesh sieves. Simple screw presses dewatered the sludge from the sieves to typically 25–30% total solids. Using fine mesh sieves with <500 microns openings was found to normally be the most economical process for primary treatment.

Los estilos APA, Harvard, Vancouver, ISO, etc.

4

Brand, Stephen K., Joel E. Schmidt, Michael W. Deem, Frits Daeyaert, Yanhang Ma, Osamu Terasaki, Marat Orazov y Mark E. Davis. "Enantiomerically enriched, polycrystalline molecular sieves". Proceedings of the National Academy of Sciences 114, n.º 20 (1 de mayo de 2017): 5101–6. http://dx.doi.org/10.1073/pnas.1704638114.

Texto completo

Resumen

Zeolite and zeolite-like molecular sieves are being used in a large number of applications such as adsorption and catalysis. Achievement of the long-standing goal of creating a chiral, polycrystalline molecular sieve with bulk enantioenrichment would enable these materials to perform enantioselective functions. Here, we report the synthesis of enantiomerically enriched samples of a molecular sieve. Enantiopure organic structure directing agents are designed with the assistance of computational methods and used to synthesize enantioenriched, polycrystalline molecular sieve samples of either enantiomer. Computational results correctly predicted which enantiomer is obtained, and enantiomeric enrichment is proven by high-resolution transmission electron microscopy. The enantioenriched and racemic samples of the molecular sieves are tested as adsorbents and heterogeneous catalysts. The enantioenriched molecular sieves show enantioselectivity for the ring opening reaction of epoxides and enantioselective adsorption of 2-butanol (the R enantiomer of the molecular sieve shows opposite and approximately equal enantioselectivity compared with the S enantiomer of the molecular sieve, whereas the racemic sample of the molecular sieve shows no enantioselectivity).

Los estilos APA, Harvard, Vancouver, ISO, etc.

5

Wang, Baocang y Yupu Hu. "Sieve Method for Polynomial Linear Equivalence". Journal of Applied Mathematics 2013 (2013): 1–8. http://dx.doi.org/10.1155/2013/872962.

Texto completo

Resumen

We consider the polynomial linear equivalence (PLE) problem arising from the multivariate public key cryptography, which is defined as to find an invertible linear transformationℒsatisfying𝒫=𝒮∘ℒfor given nonlinear polynomial maps𝒫and𝒮over a finite field𝔽q. Some cryptographic and algebraic properties of PLE are discussed, and from the properties we derive three sieves called multiplicative, differential, and additive sieves. By combining the three sieves, we propose a sieve method for the PLE problem. As an application of our sieve method, we show that it is infeasible to construct public key encryption schemes from the PLE problem.

Los estilos APA, Harvard, Vancouver, ISO, etc.

6

Pastuszka, Paweł, Zdzisław Bogdanowicz, Artur Kowalik, Krzysztof Gruszczyński y Mariusz Łapiński. "Technical aspects of circulating tumor cells (CTC) isolation using molecular sieve". Bulletin of the Military University of Technology 66, n.º 1 (31 de marzo de 2017): 41–54. http://dx.doi.org/10.5604/01.3001.0009.9483.

Texto completo

Resumen

The article presents the characteristics of circulating tumor cells (CTC) in the context of their enrichment. It presents the possibility of the use of molecular sieves in CTC isolation. It shows important technical factors affecting the efficiency of CTC enrichment using molecular sieves and indicates the necessity of compromise choice of these parameters. It shows 2D molecular sieve construction made within the Biomedical Engineering Centre of MUT. It presents the future directions of research which assumes the use of this construction for a molecular filter in the form of sieve stack. Keywords: molecular sieves, circulating tumor cells (CTC) enrichment, laser photolithography, laser ablation

Los estilos APA, Harvard, Vancouver, ISO, etc.

7

Серга, Георгий, Georgiy Serga, Александр Секисов, Aleksandr Sekisov, София Губиева y Sofiya Gubieva. "KINEMATICS INVESTIGATIONS OF BULK MATERIAL MOTION IN SCREW SIEVE. PART I". Bulletin of Bryansk state technical university 2019, n.º 11 (28 de noviembre de 2019): 27–37. http://dx.doi.org/10.30987/1999-8775-2019-2019-11-27-37.

Texto completo

Resumen

There are offered working devices of the equipment for bulk material separation (working environment) ensuring bulk material motion with high amplitude. The developed classification of screw sieves is presented, the peculiarities of conditionally cylindrical shaped screw sieves and their models are shown. The design peculiarities and technologies for the assemblage of some sieves are investigated. The investigation results of bulk motion parameters depending on design peculiarities of a screw sieve are presented.

Los estilos APA, Harvard, Vancouver, ISO, etc.

8

Wang, Li Qin, Ning Yu, Yang Han, Xiang Ni Yang y Xiu Li Zhao. "Synthesis and Characterization of the ZSM-5/MCM-41 Composite Molecular Sieves". Key Engineering Materials 480-481 (junio de 2011): 165–69. http://dx.doi.org/10.4028/www.scientific.net/kem.480-481.165.

Texto completo

Resumen

The ZSM-5/MCM-41 composite molecular sieves were synthesized in the method of hydrothermal crystallization in the presence of cetyltrimethylammonium bromide (CTMABr) as template agent. The prepared composite molecular sieves were characterized by the means of X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and the thermogravimetric and differential thermal analysis (TG-DTA). The experimental results showed that as-prepared ZSM-5/MCM-41 composite molecular sieves kept both crystal structure and compositions of ZSM-5 zeolites and MCM-41 molecular sieves. The decomposition temperature of the template agent was 293°C, and the decomposition temperature of the molecular sieve framework was higher than 800 °C. We supposed that the obtained ZSM-5/MCM-41 composite molecular sieves had high thermal stability, framework rigidity and structural stability, and could combine the properties of ZSM-5 zeolites and MCM-41 molecular sieves successfully.

Los estilos APA, Harvard, Vancouver, ISO, etc.

9

Nada, Bojić, Ružica Nikolić y Goran Manojlović. "Conformity of finished forming sieves for paper industry". Production Engineering Archives 24, n.º 24 (1 de septiembre de 2019): 29–32. http://dx.doi.org/10.30657/pea.2019.24.07.

Texto completo

Resumen

Abstract The sieves’ manufacturers that want to be competitive at the market must have the implemented quality control system. Different methods, based on taking the sample, which is a representative of the total quantity of the forming sieves production, are applied for evaluation of the sieve’s conformity. The basic characteristics of this type of the quality function are control, measuring and testing of the forming sieves’ properties at the end of the manufacturing process. The objective is to detect and separate the products that deviate from the set criteria, to remain in the factory, then to be repaired if possible or discarded in the opposite case and thus to prevent delivery of the defective sieves to the paper manufacturers.

Los estilos APA, Harvard, Vancouver, ISO, etc.

10

Ming, Ping Mei, Y. J. Li, Y. L. Wang y W. J. Jiang. "Fabrication of Micro-Precision Sieves with High Open Area Percentage Using Micro-Electroforming Technology". Advanced Materials Research 426 (enero de 2012): 64–68. http://dx.doi.org/10.4028/www.scientific.net/amr.426.64.

Texto completo

Resumen

Precision metal sieve-sheets are one of the key components of several high-tech products. Fabrication of the precision sieve-sheets possessing high open area percentage, large thickness and good quality simultaneously has always been a tickler in micro-machining area. In this paper, aiming to manufacture micro-sieves with open areas of about 90% and good quality, micro-electroforming was taken as a major process means, and the technical points and technical difficulties of some key process steps in the preparation of micro-precision sieves were explored emphatically. Meanwhile, operational conditions were optimized and major technological parameters were selected optimally. Using the optimal conditions as well as the optimum parameters, two specifications of hexagon micromesh sieve-sheets whose side length, open-area percent and sheet-thickness was 210μm, 88%, (120±3)μm and 520μm, 92%, (100±2)μm, respectively, were successfully obtained. The electroformed sieves are characterized by flat and smooth surfaces of aperture walls, sharp edge definition, rigid and homogeneous structures and well-distributed mesh.

Los estilos APA, Harvard, Vancouver, ISO, etc.

11

Palonen, V. y M. Oinonen. "Molecular Sieves in 14CO2 Sampling and Handling". Radiocarbon 55, n.º 2 (2013): 416–20. http://dx.doi.org/10.1017/s0033822200057544.

Texto completo

Resumen

Molecular sieves are a promising way to sample and manipulate gaseous samples for radiocarbon analyses. Molecular sieve material can adsorb CO2 selectively, enabling sampling of CO2 from large air volumes in a small amount of adsorbent. The sieve material can be regenerated via heating and reused without removing the sieve material from its container. This results in ease of use and reduced risks of atmospheric contamination. Because sieve container volume is small and can be filled with synthetic air or nitrogen, it does not introduce underpressure to the system under study. Hence, sieves are suitable for many different experimental setups, from collection of CO2 from small soil chambers to atmospheric CO2 collection. The most common sieve material in use for sampling CO2 is the 13X zeolite. For environmental measurements starting this year, we have studied the properties of 13X zeolites in more detail. For reliable 14CO2 sampling, there are several caveats that should and can be avoided. In this contribution, we discuss these caveats and solutions to optimize the molecular sieve sampling process.

Los estilos APA, Harvard, Vancouver, ISO, etc.

12

Гиевский, Aleksey Gievskiy, Чернышов, Aleksey Chernyshov, Оробинский y Vladimir Orobinskiy. "Justification of allocation scheme and the ratio of sieves in screen shoes". Forestry Engineering Journal 3, n.º 3 (12 de diciembre de 2013): 126–33. http://dx.doi.org/10.12737/1776.

Texto completo

Resumen

The results of the feasibility studies of allocation scheme of sieves in the screen shoe to improve performance are given. Inves-tigations were carried out in a pilot plant consisting of two-aspiration pneumatic sys-tem and screen shoe with a ball-cleaning of sieves, controlled vibration frequency and location in one tier of up to three sieves with a length of 0.99 m. Permissible unit stress were obtained for grains and sorting sieve for cleaning piles of winter wheat at the mill vibration amplitude of 0.03 m in and a frequency of 350 min-1.

Los estilos APA, Harvard, Vancouver, ISO, etc.

13

Peng, Liping, Huihui Feng, Zhenqian Wang, Haoyu Wang, Huan Yang y Huan Huang. "Screening Mechanism and Properties of a Cantilevered Vibrating Sieve for Particles Processing". Applied Sciences 9, n.º 22 (15 de noviembre de 2019): 4911. http://dx.doi.org/10.3390/app9224911.

Texto completo

Resumen

Screening of fine wet particles or near-aperture particles by traditional screen devices is often not quite effective for sieve plugging. Different from traditional rigid regular mesh sieves, a cantilevered vibrating sieve (CVS) with open screen holes, composed of cantilevered sieve rods, was proposed in this paper. The CVS proved to have a higher screen-penetrating probability relative to traditional sieves. By establishing a bending vibration model for the CVS, it can be found that additional vibrations may emerge during the screen body motion, and a smaller difference between the natural circular frequency and the vibration frequency will achieve a larger vibration of cantilevered sieve rod. On this basis, this investigation also analyzed anti-plugging mechanism of the CVS and systematically discussed the influence laws of the geometric parameters and vibration parameters of the sieve on screening efficiency by the discrete element method.

Los estilos APA, Harvard, Vancouver, ISO, etc.

14

Sichamnan, Surachet, Suriyawong Trongthiang, Thephatsadin Chimnin y Namphon Pipatpaiboon. "EFFICIENCY OF ESSENTIAL OIL DISTILLERS BY A CONVECTION ROD SIEVE". Journal of Southwest Jiaotong University 57, n.º 4 (29 de agosto de 2022): 562–71. http://dx.doi.org/10.35741/issn.0258-2724.57.4.25.

Texto completo

Resumen

This study aimed to enhance the efficiency of an essential oil distiller by using a convection rod sieve. Three types of rod sieves were used in this study: normal sieve (NS), convection short rod sieve (CSRS) and convection long rod sieve (CLRS). These sieves were installed in a 500 liter essential oil distiller, which was operated by water and steam distillation methods. Zingiber cassumunar was used as the raw material for extracting the essential oil. For each test cycle, 150 kg of the raw material was distilled for 8 h. The results obtained under the same conditions from the three sieves, CSRS, CLRS, and NS, were compared. The CSRS facilitated a faster penetration and dissipation of heat from the steam to the raw material. The results revealed that CSRS, which had a convection rod extending into the center of the sieve, could enhance the heat transfer rate by increasing the heat convection of the steam, which penetrated and dispersed into the raw material at 7.18 ± 0.35 kW. Furthermore, using CSRS with an essential oil distiller yielded maximum oil content of 2.12% (v/w) and 1.85% (w/w), which was higher than the oil obtained from CLRS and NS. The effectiveness of the essential oil distiller using a CSRS indicated that a maximum distillation efficiency of 85.94% was achieved, which was higher than that of CLRS and NS.

Los estilos APA, Harvard, Vancouver, ISO, etc.

15

Hannibal, Joseph T., Michael E. Williams y Gary L. Jackson. "An inexpensive source of dolomite powder for use with airbrasive units". Journal of Paleontology 62, n.º 2 (marzo de 1988): 316. http://dx.doi.org/10.1017/s002233600003002x.

Texto completo

Resumen

In the past few years the Cleveland Museum of Natural History has received several inquiries as to our source of dolomite for use with S.S. White® industrial airbrasive units. We have been using inexpensive, “agricultural” dolomite with these units for several years. This source was “discovered” by testing of a wide variety of dolomite sources by Peter Kotulak, a former preparator at the Museum, under the direction of M.E.W. We are currently using OHSO® Pulverized Limestone, a kiln-dried dolomitic limestone recommended for agricultural, and lawn and garden, use. It is produced by the Ohio® Lime Co., of Woodville, Ohio. A 22.7 kg (50 pound) bag costs $2.25, and is available at building supply companies. The dolomite must be sieved and dried to prevent clogging of the unit's line and nozzle. We use a Ro-Tap® Testing Sieve Shaker to sieve the material, with #30 (595 micron), #60 (250 micron), and #100 (150 micron) U.S.A. standard testing sieves. An incandescent desk lamp can be placed over an open container of the sieved dolomite to keep it dry. Used powder may be re-sieved for reuse if desired.

Los estilos APA, Harvard, Vancouver, ISO, etc.

16

Lemonidis, Ioannis, Dimitra C. Banti, Christos A. Tzenos, Sotirios D. Kalamaras, Thomas A. Kotsopoulos y Petros Samaras. "Energy Valorization of Fine Screenings from a Municipal Wastewater Treatment Plant". Energies 15, n.º 21 (4 de noviembre de 2022): 8236. http://dx.doi.org/10.3390/en15218236.

Texto completo

Resumen

The aim of this paper was to evaluate the characteristics and the energy potential for the methane production of fine screenings collected from the primary stage of a municipal wastewater treatment plant, and assess the impact on the properties and the oxygen demand of the aqueous effluents downstream from the sieves. Commercial filter bags with sieve openings of 3000, 1250, 1000, and 300 μm were used for the collection of screenings following a measurement of their biochemical methane potential. It was revealed that solid fractions from the sieves with a large size presented a high net methane production capacity exceeding 900 mL/g VS, but the gas production rate was rather slow, requiring a long time to reach the final value. However, cumulative solid fractions containing particles with a size larger than 300 μm had a lower net methane production, about 700 mL/g VS, but with a faster rate, resulting in almost 80% of the total volume released in 30 days. Aqueous samples downstream from the sieves presented decreasing organic matter content by sieve size and reduced the requirements for aeration oxygen. The installation of fine sieves in existing municipal wastewater treatment plants, therefore, may be beneficial due to the enhancement of biogas production and a reduction in the oxygen consumption of the activated sludge process.

Los estilos APA, Harvard, Vancouver, ISO, etc.

17

Ravichandran, S., S. Muthukkumar y M. Sabarish. "Design and Development of Diminution of Multiplier in FIR Sieve Consuming Mutual Sub-Expression Removal Algorithm". Asian Journal of Science and Applied Technology 10, n.º 2 (5 de noviembre de 2021): 26–33. http://dx.doi.org/10.51983/ajsat-2021.10.2.3072.

Texto completo

Resumen

The difficulty of Finite-Impulse-Response (FIR) sieve out is ruled with means of that wide variety of adders or subtractors that are consumed toward enforce these co-green multipliers. The Common-Sub-expression-Elimination (CSE) set of rules is founded totally at that Canonical-Signed-Digit (CSD) depiction of clear out co-efficient pro imposing stumpy difficulty FIR sieves. Now, decrease of multiplier inside rectilinear phase FIR sieves is completed through changing this multiplier quantity toward Minimum-Signed-Powers-of-Two (MNSPT) or Canonical-Signed-Digit (CSD) illustration of this multiplier respectively. This multiplier may be executed consuming a sequence of changes and accompaniments or deductions. This CSE algorithm is expended toward discover and dispose of additional commonplace sub-expressions amongst sieve coefficients whichever ends up inside energy and vicinity convertible at the same time as executed inside FIR sieves. This Common-Sub-expression-Elimination (CSE) approach toward be consumed pro this VLSI layout will outcome in condensed multiplier inside Finite-Impulse-Response (FIR) clear out by a trivial quantity of adders and records.

Los estilos APA, Harvard, Vancouver, ISO, etc.

18

Bakum, M. V., S. O. Kharchenko, S. Y. кovalyshyn, M. M. Krekot, F. M. Kharchenko, O. P. Shvets, P. Kiełbasa y A. Miernik. "Identification of parameters of the separation process of safflower seed material on sieves". Journal of Physics: Conference Series 2408, n.º 1 (1 de diciembre de 2022): 012013. http://dx.doi.org/10.1088/1742-6596/2408/1/012013.

Texto completo

Resumen

Abstract Separation of seed mixtures for the purpose of their purification or calibration by fractions is a mandatory technological operation in the processing of most crops. Due to its properties, the process of separation of seed mixtures of individual crops has undefined parameters or low efficiency of its flow. A similar seed material is safflower, the parameters of the purification process of which were determined in the work taking into account different methods of separation of the components of the mixture. The work involves determining the parameters of the holes of the sieves and the scheme of their installation during the separation of the seed mixture of safflower, provided the maximum quality of seeds. For this purpose, the dimensional characteristics of safflower seeds and characteristic impurities were determined, which allowed to determine the possibilities of their qualitative separation. As a result of experiments, variation curves of dimensional characteristics of safflower seed mixture components in thickness and width were established. To imitate hard-to-separate components, winter wheat and pea grains were added to safflower seeds. The efficiency of sieve separation was also determined taking into account different types of sieve openings. Studies of the process of purification of safflower seed mixture were performed both on traditional flat stamped sieves and on the proposed sieves with activators. A study on the separation of safflower seed mixtures on traditional sieves with round holes with a diameter of 5.0 mm and rectangular holes with a width of 3.0 mm has been carried out. For the first time, a sieve with five-petalled epicycloid and volume activators was used to clean the seed mixture, which, thanks to the innovative design, allows us to increase the efficiency of the separation process. For the first time, a well-grounded method of determining the coefficient, which comprehensively takes into account the parameters of holes and jumpers, can be used to optimize the parameters of seed and grain cleaning machines. The separation efficiency of the safflower seed mixture was determined both by the content of fractions and by the indicators of 1000 seed weight, germination energy and seed germination. It has been found that to increase the productivity and quality of separation, it is advisable to use sieves with sieve activators: the upper sieve with five-petalled epicycloid activators 5 mm, and the lower with elongated holes 3 mm wide as well as volume activators.

Los estilos APA, Harvard, Vancouver, ISO, etc.

19

Xenakis, Iannis y John Rahn. "Sieves". Perspectives of New Music 28, n.º 1 (1990): 58. http://dx.doi.org/10.2307/833343.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

20

Poullet, Muñoz-Perez, Poortvliet, Mera, Contreras y Lopez. "Influence of Different Sieving Methods on Estimation of Sand Size Parameters". Water 11, n.º 5 (26 de abril de 2019): 879. http://dx.doi.org/10.3390/w11050879.

Texto completo

Resumen

Sieving is one of the most used operational methods to determine sand size parameters which are essential to analyze coastal dynamics. However, the influence of hand versus mechanical shaking methods has not yet been studied. Herein, samples were taken from inside the hopper of a trailing suction dredger and sieved by hand with sieves of 10 and 20 cm diameters on board the dredger. Afterwards, these same samples were sieved with a mechanical shaker in the laboratory on land. The results showed differences for the main size parameters D50, standard deviation, skewness, and kurtosis. Amongst the main results, it should be noted that the highest values for D50 and kurtosis were given by the small sieves method. On the other hand, the lowest values were given by the mechanical shaker method in the laboratory. Furthermore, standard deviation and skewness did not seem to be affected by the sieving method which means that all the grainsize distribution was shifted but the shape remained unchanged. The few samples that do not follow these patterns have a higher percentage of shells. Finally and definitely, the small sieves should be rejected as a sieving method aboard.

Los estilos APA, Harvard, Vancouver, ISO, etc.

21

Chang, Chen Yu, Yao Chuan Lee, Ching Hsing Lin, Jyh Wei Lee, Yu Jie Chang y Jian Huan Chen. "Degradation of Volatile Acetone by a Photocatalytic Reactor with TiO₂ Coated Sieve". Advanced Materials Research 123-125 (agosto de 2010): 919–22. http://dx.doi.org/10.4028/www.scientific.net/amr.123-125.919.

Texto completo

Resumen

The TiO2 thin films were coated on the 100 meshes stainless steel 304 (SS304) sieves by using the sol-gel method followed by a thermal treatment at 200oC. The prepared TiO2-coated sieves were then employed to setup a photocatalytic reactor for evaluating their abilities on the degradation of VOCs (volatile organic compounds). The UV lamp was enveloped with a cylinder TiO2-coated sieve and located in the center of the reactor. A VOCs diffusing tube was applied to yield acetone under water bath. The yielded gaseous acetone was enforced to pass through the TiO2-coated sieves and reacted by photocatalytic reaction. Both the inflow gas and off-gas were monitored by a PID (photoionization detector) sensor for calculating the treat efficiencies under various conditions. The results showed that the amorphous structure was observed on the TiO2 films after sol-gel method, whereas the crystalline anatase phase was found after annealing at 200oC. The SEM images showed that the surface morphology of TiO2 coated SS304 sieves was very similar to that of uncoated sieves, demonstrating a good uniformity and thin thickness of the sol-gel coating method derived in this work. It was observed that most volatile acetone (almost 100%) was removed after treated with the designed photocatalytic reactor under a high fed flow rate (0.5- 2.0 l/min). As compared with the control experiments (UV OFF test), the adequate photocatalytic abilities of this developed TiO2 coated sieves were demonstrated. With the advantages of high contacting area with VOCs, low headloss, durable substrate and easy maintenance, the TiO2-coated sieves possessed a high potential for applying on the photocatalytic degradation of indoor air pollutants.

Los estilos APA, Harvard, Vancouver, ISO, etc.

22

Moskovskiy, Maksim, Victor Khamuev, Aleksei Dorokhov y Stanislav Gerasimenko. "Determining optimal kinematic parameters of a screen shoe used for separating breeding seed samples". MATEC Web of Conferences 298 (2019): 00044. http://dx.doi.org/10.1051/matecconf/201929800044.

Texto completo

Resumen

In the post-harvest processing of breeding material, the absence of a sieve machine of appropriate productivity that meets all the requirements for breeding machines is relevant today. For research, a mock stand of the sieve machine was used, on which the kinematic parameters of the sieve mill and the tilt angles of the sieves were determined.

Los estilos APA, Harvard, Vancouver, ISO, etc.

23

Ramsay, P. M., S. D. Rundle, M. J. Attrill, M. G. Uttley, P. R. Williams, P. S. Elsmere y A. Abada. "A rapid method for estimating biomass size spectra of benthic metazoan communities". Canadian Journal of Fisheries and Aquatic Sciences 54, n.º 8 (1 de agosto de 1997): 1716–24. http://dx.doi.org/10.1139/f97-081.

Texto completo

Resumen

The construction of biomass size spectra in aquatic environments suffers from two main problems: (i) it is a labour-intensive process, and (ii) there is a lack of conformity in methodologies. This study evaluates a technique that produces biomass spectra for benthic metazoans from subsamples stratified using a geometric series of nested sieves. The technique was applied to metazoan communities from three sites, two freshwater and one brackish water, on a small river in southern Britain. Random subsamples of animals from each sieve size were measured using image analysis and showed significant differences in body size, as equivalent spherical diameter (ESD), among all but two sieves. There was no significant difference in ESD among sites. Despite the propensity for long thin animals to pass lengthwise through meshes, sieves contained a consistent range of individual body sizes. Mean individual body size and abundance data for each sieve were used to calculate total biomass. These size spectra were consistent with those from previous studies, and it is hoped that this method will encourage the wider application and more rigorous measurement of biomass size spectra in aquatic ecology.

Los estilos APA, Harvard, Vancouver, ISO, etc.

24

Vasylkovskyi, Olexiy, Sergiy Leshchenko, Sergiy Moroz, Olexandr Nesterenko y Ludmyla Molokost. "Before Creating the Concept of the «Ideal» Grain Separator Sieve". National Interagency Scientific and Technical Collection of Works. Design, Production and Exploitation of Agricultural Machines, n.º 50 (2020): 52–58. http://dx.doi.org/10.32515/2414-3820.2020.50.52-58.

Texto completo

Resumen

The article presents considerations for creating conditions for the intensification of the process of grain separation by geometric features. The review of constructions and the analysis of work of known sieve surfaces from a position of possibility of maintenance of high indicators of technological efficiency at the expense of acceleration of orientation of particles concerning sieve apertures is carried out. It is established that the most favorable orientation conditions are provided by the surfaces formed by longitudinal elements of small cross-section of streamlined shape, which minimize the possibility of placing particles on them in positions of stable equilibrium. Theoretical possibilities of increasing the living cross-sectional areas and live cross-sectional coefficients of sieve canvases without cross-sections are revealed. The dependences of the total width of the longitudinal sections and the coefficient of the living cross section of the sieves on the width of the longitudinal sections for different sieves are given. This makes it possible to visually assess the need to increase the living cross section of the sieves by reducing the width of the longitudinal sections that form them. A significant reduction in the width of the partitions is possible due to the use of new materials - braided cords made of ultra-high molecular weight polyethylene type Spectra / Dyneema, which provide high mechanical strength and wear resistance with «absolute» inextensibility.

Los estilos APA, Harvard, Vancouver, ISO, etc.

25

Luzan, Petro, Ruslan Kisilyov, Olena Luzan y Oleh Kyslun. "Theoretical Aspects of Grain Separation on an Inertial-gravity Separator Sieve". National Interagency Scientific and Technical Collection of Works. Design, Production and Exploitation of Agricultural Machines, n.º 51 (2021): 95–103. http://dx.doi.org/10.32515/2414-3820.2021.51.95-103.

Texto completo

Resumen

The aim of the article is to substantiate the design, derivation and approbation by calculations of formulas for determining the parameters of the sieve with slits that expand in the direction of movement of the processed material. It is established that grain cleaning machines, which currently work on agricultural and processing enterprises with flat sieves, have been used for many years, are well studied and improved, their technical and economic indicators have reached maximum values. The problem is that to ensure the proper operation of existing grain cleaning machines with traditional flat sieves, a large amount of energy costs are spent on additional operations that are not directly related to the separation process, but without them the normal operation of the machine is impossible. This is directly the transportation of grain and cleaning the sieves from grains that are stuck in the cracks and degrade the quality of their work. The substantiation of the technological scheme of the inertial-gravity separator sieve with slits expanding in the direction of movement of the processed material is performed and the influence of its main parameters on the efficiency of separation of grain mixtures is established. The regularities of the movement of the grain mixture on the surface of the sieve are determined, when favorable conditions are created for the passage through the slits of particles that can pass through it. The method of calculation of the basic geometrical and kinematic parameters of a sieve is offered. To implement the proposed calculation method developed software that allows you to convert blocks developed in analytical form of the calculation method in a form that meets the requirements of the architecture of mathematical models and implements the numerical methods of Runge-Kutt and Nelder-Mead. Tests have shown that the quality of separation of wheat grain on the proposed sieve increases by 12-14% compared to existing ones. When implementing the sieves of the proposed design, the issue of influencing the quality of separation of the magnitude of the bar deflection in the end part and their limits for different crops remains unresolved.

Los estilos APA, Harvard, Vancouver, ISO, etc.

26

Fu, Jun, Haikuo Yuan, Rongqiang Zhao, Xinlong Tang, Zhi Chen, Jin Wang y Luquan Ren. "Machine-Vision-Based Algorithm for Blockage Recognition of Jittering Sieve in Corn Harvester". Applied Sciences 10, n.º 18 (10 de septiembre de 2020): 6319. http://dx.doi.org/10.3390/app10186319.

Texto completo

Resumen

Jittering sieve is a significant component of corn harvester, and it is used to separate kernels from impurities. The sieves may be blocked by kernels during the separating process, leading to the reduction of working performance. Unfortunately, the automatic recognition of blockage has not been studied yet. To address this issue, in this study we develop machine-vision-based algorithms to divide the jittering sieve into sub-sieves and to recognize kernel blockages. Additionally, we propose the metric to evaluate blocking level of each sub-sieve, aiming to provide the basis for automatic blockage clearing. The performance of the proposed algorithm is verified through simulation experiments on real images. The success ratio of edge determination reaches 100%. The mean cross-correlation coefficient of the blockage levels and the actual numbers of blocked kernels for all test scenes is 0.932. The results demonstrate the proposed algorithm can be used for accurate blockage recognition, and the proposed metric is appropriate for evaluating the blockage level.

Los estilos APA, Harvard, Vancouver, ISO, etc.

27

Giyevskiy, A. M., A. P. Tarasenko, V. I. Orobinskiy y A. V. Chernyshov. "Increasing the performance of two-aspiration pneumatic system of a multipurpose air-and-screen grain cleaner". Traktory i sel hozmashiny 81, n.º 5 (15 de mayo de 2014): 32–34. http://dx.doi.org/10.17816/0321-4443-65605.

Texto completo

Resumen

Results of the experimental investigations substantiating withdrawal of bottom grain layer from the end of sorting sieves without conveying to channel of post-sieve aspiration in grain cleaning mode for market objectives, are given.

Los estilos APA, Harvard, Vancouver, ISO, etc.

28

Crowder, Cyrus E., Juan M. Garces y Mark E. Davis. "Using X-ray Powder Diffraction to Determine the Structure of VPI-5 - A Molecular Sieve with the Largest Known Pores". Advances in X-ray Analysis 32 (1988): 507–14. http://dx.doi.org/10.1154/s0376030800020838.

Texto completo

Resumen

The synthesis of a new family of aluminophosphate-based molecular sieves containing pores defined by 18 tetrahedrally linked atoms has been described by Davis et al at Virginia Polytechnic Institute (VPI). This development reprsents the first reposted synthesis of a moleoular sieve with pores larger than those defined by 12 tetrahedrally linked atoms. This material has been shown to readily absorb triisopropyl benzene and exhibits a pore size distribution, determined from, its argon adsorption isotherm, which suggests the existence of molecular sieve pores larger than those found in known molecular sieves. Confirmation of a pore defined by 18 tetrahedrally linked aluminum and phosphorus atoms was accomplished by crystallographic structure determination using X-ray powder diffraction data. Single crystal methods were impossible due to an inability to synthesize crystals of suitable size. Details of the structure determination are reported in this work.

Los estilos APA, Harvard, Vancouver, ISO, etc.

29

Wang, Li Qin, Yang Han, Xiu Jun Fu, Hai Tao Wu, E. Chang, Hai Ying Wang, Quan Huo y Rui Jun Zhang. "Synthesis and Characterization of MCM-41 Molecular Sieves Nanoparticals". Advanced Materials Research 662 (febrero de 2013): 214–17. http://dx.doi.org/10.4028/www.scientific.net/amr.662.214.

Texto completo

Resumen

Nanoparticals of MCM-41 molecular sieves were synthesized at near room temperature with cetyltrimethylammonium bromide (CTAB) as template agent. The prepared samples were characterized by the means of scanning electron microscopy (SEM), X-ray powder diffraction (XRD), fourier transform infrared spectroscopy (FT-IR), N2 adsorption tests, thermogravimetric and differential thermal analysis (TG-DTA). The results suggested that morphology of MCM-41 molecular sieves samples with high crystallinity was almost uniform spherical, and the particles size was almost less than 100 nm. The adsorption-desorption isotherms were corresponded to typical type IV isotherms with the hysteresis loop of type H2, which showed the samples had mesoporous structure. The pore size distribution of samples were 1.69 nm and 3.58 nm, and the specific surface areas was up to 752.23 m2/g. The decomposition temperature of template agent CTAB was around 327 °C, while the framework for MCM-41molecular sieves was stable. So MCM-41 molecular sieve samples synthesized at near room temperature had excellent physical properties.

Los estilos APA, Harvard, Vancouver, ISO, etc.

30

Paulsrud, Bjarne, Bjørn Rusten y Bjørn Aas. "Increasing the sludge energy potential of wastewater treatment plants by introducing fine mesh sieves for primary treatment". Water Science and Technology 69, n.º 3 (18 de noviembre de 2013): 560–65. http://dx.doi.org/10.2166/wst.2013.737.

Texto completo

Resumen

The objective of this study was to compare some basic characteristics of sludge from fine mesh sieves (sieve sludge) with sludge from primary clarifiers (primary sludge) regarding their energy potential with a focus on anaerobic digestion and/or incineration. Nineteen samples of sludge from fine mesh sieve plants (most of them without fine screens and grit chambers as pre-treatment) and 10 samples of primary sludge were analysed for the content of dry solids (DS), volatile solids (VS), chemical oxygen demand (COD), calorific value and methane potential. The results demonstrated that the sieve sludges have significantly higher VS content and higher methane potential than primary sludges, clearly indicating an increased sludge energy potential if fine mesh sieves are used for primary treatment instead of primary clarifiers at wastewater treatment plants with anaerobic digesters. If the sludges from primary treatment are to be incinerated or used as fuel in cement kilns, there is no significant difference in energy potential (given as calorific values) for the two types of primary treatment.

Los estilos APA, Harvard, Vancouver, ISO, etc.

31

Caro, Jürgen. "Molecular Sieves". Zeitschrift für Physikalische Chemie 212, Part_1 (enero de 1999): 119–20. http://dx.doi.org/10.1524/zpch.1999.212.part_1.119.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

32

Machado, Federico, Przemyslaw Zagrajek, Juan A. Monsoriu y Walter D. Furlan. "Terahertz Sieves". IEEE Transactions on Terahertz Science and Technology 8, n.º 1 (enero de 2018): 140–43. http://dx.doi.org/10.1109/tthz.2017.2762292.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

33

Xia, Lixin, Jiarui Xia, Ran Wei, Ying Sui, Zhipeng Sun, Xuehua Song, Peng Song y Lini Yang. "Facile Synthesis of Micron-Sized Hollow Silver Spheres as Substrates for Surface-Enhanced Raman Scattering". International Journal of Photoenergy 2014 (2014): 1–7. http://dx.doi.org/10.1155/2014/745913.

Texto completo

Resumen

A well-designed type of micron-sized hollow silver sphere was successfully synthesized by a simple hard-template method to be used as substrates for surface-enhanced Raman scattering. 4 Å molecular sieves were employed as a removable solid template. [Ag(NH3)2]+was absorbed as the precursor on the surface of the molecular sieve. Formaldehyde was selected as a reducing agent to reduce [Ag(NH3)2]+, resulting in the formation of a micron-sized silver shell on the surface of the 4 Å molecular sieves. The micron-sized hollow silver spheres were obtained by removing the molecular sieve template. SEM and XRD were used to characterize the structure of the micron-sized hollow silver spheres. The as-prepared micro-silver spheres exhibited robust SERS activity in the presence of adsorbed 4-mercaptobenzoic acid (4-MBA) with excitation at 632.8 nm, and the enhancement factor reached ~1.5 × 106. This synthetic process represents a promising method for preparing various hollow metal nanoparticles.

Los estilos APA, Harvard, Vancouver, ISO, etc.

34

Sun, Jingjing, Nan Zhang, Haibo Jin, Xuefeng Mao, Guangxiang He, Junfang Li, Zihao Yan et al. "The catalytic performance of acid-modified Hβ molecular sieves for environmentally friendly acylation of 2-methylnaphthalene". Green Processing and Synthesis 11, n.º 1 (1 de enero de 2022): 732–46. http://dx.doi.org/10.1515/gps-2022-0067.

Texto completo

Resumen

Abstract 2,6-Methylacylnaphthalene is an important organic chemical raw material, mainly used as a precursor for synthesizing polyethylene 2,6-naphthalene dicarboxylate (PEN). The heterogeneous catalyst molecular sieve catalyzes the acylation of 2-methylnaphthalene to synthesize β,β-methylacylnaphthalene, which has good activity, is green and environmentally friendly, with simple post-treatment. Different molecular sieves and reaction solvents were selected, and Hβ molecular sieves were more suitable for the acylation reaction of 2-methylnaphthalene. The reaction results were better when sulfolane was used as a solvent in this paper. The catalytic performances of citric acid-modified Hβ molecular sieve (SiO2/Al2O3 of 25) and unmodified molecular sieve were investigated and compared. The results showed that modification with low-concentration citric acid increased the amount of mediate strong acid and Bronsted acid, the specific surface area, pore volume, and pore size of Hβ zeolite. When the concentration of citric acid was 0.3 mol·L−1, the modification time was 48 h and the calcination at 550°C for 3 h had the best catalytic activity. By further optimizing the acylation process, the conversion rate of 2-methylnaphthalene increased to 88.82%, and the yield of β,β-methyl propyl naphthalene increased to 82.12%.

Los estilos APA, Harvard, Vancouver, ISO, etc.

35

Chang, Yi Tang, Chin Hsing Lin, Yu Jie Chang y Cheng Che Chiang. "Bactericidal Activity of Photocatalytic Reaction in Aqueous Media by the TiO₂-Coated Stainless Steel Sieves". Advanced Materials Research 347-353 (octubre de 2011): 1906–10. http://dx.doi.org/10.4028/www.scientific.net/amr.347-353.1906.

Texto completo

Resumen

Thin films with the high content of Ti coated on the stainless steel (SS) sieves were successfully prepared through the sol gel method. Photocatalytic reaction on the TiO2-coated SS sieves with UVA (ultraviolet light with the range of 315-400 nm) radiation is effective to destroy three selected bacterial strains with log-phase period. As a result, bactericidal ability was achieved to 77% in aqueous media. Amount of bacterial numbers, 3.4×107CFU/ml can be removed in this study, compared with our previous study, 1.85×103CFU/ml in the air media. Good contribution of bactericidal ability in 385 nm UVA radiation or heavy metals including Fe, Mn, Cr, Ni and Ti from the SS sieve was obtained as the range of 30-76%. The percentage of 10-17% contribution of bactericidal ability was increased with the photocatalytic reaction additive. It concluded the performance of bactericidal ability in aqueous solution is ascribed to the combination of UVA radiation, heavy metals on the sieve and photocatalytic reaction. The SS sieve coated with TiO2particles can be applied as a disinfectant for the effluent of wastewater treatment plant or water supply system in the future.

Los estilos APA, Harvard, Vancouver, ISO, etc.

36

Barros, Renato Téo de, Cibele Chalita Martins, Tatiane Sanches Jeromini, Givanildo Zildo da Silva y Arthur Bernardes Cecílio Filho. "Physiological quality of parsley seeds in function of size". Semina: Ciências Agrárias 42, n.º 3Supl1 (22 de abril de 2021): 1499–510. http://dx.doi.org/10.5433/1679-0359.2021v42n3supl1p1499.

Texto completo

Resumen

Parsley seeds are commercialized without classification by size during processing, unlike other crops. This classification procedure allows the standardization of seed size for high precision in sowing, disposal of unwanted material, and selection of high quality seeds. The aim of this study was to verify the effect of seed size on germination, vigor, and yield performance of two parsley cultivars. Seeds from eight lots of parsley of ‘Portuguesa’ and ‘Chacareira’ cultivar were separated into three size classes, represented by the seeds retained in the sieves of 0.84, 1.00 and 1.41mm mesh opening. After classification, seeds were evaluated in the laboratory for water content, germination percentage, first count, and thousand seed weight. In the field, the fresh and dry weight of aerial part and the final number of plants (stand) were evaluated after 78 days of sowing. The experimental design was the completely randomized design in an 8 x 3 factorial scheme (eight lots and three sieve opening) with four replicates, for both cultivars. Data obtained were subjected to analysis of variance and means were compared using Tukey test at 5% probability level. It was concluded that the parsley seeds separated by the 1.41 mm sieves showed higher vigor, and consequently, greater success in stand establishment at the field than those separated by other sieve size. The use of sieves in the classification of parsley seeds helps in obtaining lots with superior physiological quality.

Los estilos APA, Harvard, Vancouver, ISO, etc.

37

Nikolić-Ivanović, Marijana, Olivera Đokić, Vladimir Milićević, Suzana Stefanović y Bratislav Milić. "Suitability of aggregates gradation for base and subbase layers of pavement". Tehnika 76, n.º 3 (2021): 291–301. http://dx.doi.org/10.5937/tehnika2103291n.

Texto completo

Resumen

The assessment of the suitability of the granulometric composition of the crushed stone aggregates (CSA) for an unbound base and subbase layers of pavement, in the Republic of Serbia is done based on the defined gradation bands, uniformity degree (Cu), coefficient of curvature (Cz), percentage of fines and percentage of particles passing a 0.02 mm sieve. On the other hand, standards which define the quality requirements of aggregates and unbound mixtures for road construction SRPS EN 13242 and SRPS EN 13285 introduce a significantly different approach to the assessment of the granulometric composition suitability. Categories are defined. Each category includes a particular boundary band, tolerances on sieves, differences in values passing each sieve. The categories are defined depending on the field of the application. For seven CSA 0/31.5 mm used for the construction of Corridor XI, a comparative analysis of the granulometric composition suitability was performed according to the requirements of the existing Technical Specifications (TS) of PE "Roads of Serbia" (PERS) and the specified SRPS EN standards. The analysed curves satisfy those technical requirements, but vary in categories from the most severe mixtures of the normal granulometric composition of the GA category, to the open mixtures of the GP category. It was concluded that the principle based on the defining allowed tolerances on the sieves and between the sieves, is more suitable for field control of of the granulometric composition and the good granularity of the aggregates. Technical Specifications should be modified to this approach.

Los estilos APA, Harvard, Vancouver, ISO, etc.

38

Madaloz, José Carlos Cazarotto, Alcir José Modolo, Juan Paulo Xavier de Freitas, José Ricardo da Rocha Campos, Murilo Mesquita Baesso, Lucas Dotto y Emerson Trogello. "Distribution of corn plants in a pneumatic system with different vacuum pressure adjustments and seed sieves". OCTOBER 2020, n.º 14(10):2020 (20 de octubre de 2020): 1568–74. http://dx.doi.org/10.21475/ajcs.20.14.10.p2316.

Texto completo

Resumen

The use of seeders with pneumatic distribution systems is increasingly demanding for plantation of corn crop. Knowledge about the operation and adjustments of the components of agricultural machines is fundamental to increase the good distribution of plants and to ensure higher productivity. The main goal of this research was to evaluate the influence of the size of the corn seed sieve under different vacuum pressure regulations on a pneumatic distribution system, to understand the longitudinal uniformity of the plants, as well as the final and individual productivity per plant. The vSet® (Precision Planting®) pneumatic distribution system equipped with 4 corn seed sieves (C1, C4, R1, and R4) subjected to 4 different vacuum pressure adjustments (7, 12, 17 and 22 in H2O-1) was applied as treatments on corn hybrid 30F53VYH. The design used was that of randomized blocks, with subdivided plots and 4 replications. The main plot presented the vacuum pressures and the subplots presented the sieves, each composed of two sowing lines of 20 m in length. The results showed that low vacuum pressure resulted in increased unevenness between corn spacings and consequently lower yield. Smaller sieves showed less gaps and higher percentages of normal spacing. The larger sieves showed higher standard deviation and more gaps. Regular and uneven gaps provided a higher number of grains per row, higher number of grains per corn spike and a higher grain yield per corn spike.

Los estilos APA, Harvard, Vancouver, ISO, etc.

39

Tkachev, V., N. Borodin, A. Knyazev, R. Borovikov y V. Lebedev. "Improving the efficiency of separating machines equipped with flat oscillating sieves". IOP Conference Series: Earth and Environmental Science 839, n.º 5 (1 de septiembre de 2021): 052026. http://dx.doi.org/10.1088/1755-1315/839/5/052026.

Texto completo

Resumen

Abstract The article deals with the separating machines equipped with flat sieves with various types of holes used for cleaning from impurities and sorting into fractions by size. It is noted that the main disadvantage of these machines is that in the process of their operation, the openings of the sieves are clogged by the separation products, which leads to a decrease in the separation efficiency, as well as a decrease in the productivity of the machines. It is mentioned that the most acute problem of cleaning the openings of sieves is when separating tree seeds. It is possible to increase the efficiency of the separating machines by using cleaning mechanisms that allow the seeds stuck in the holes to be pushed out when the machines are operating. A mechanism for cleaning the holes of sieves is proposed, equipped with cylindrical working bodies on which gears are mounted that are engaged with toothed rails. In the course of experimental studies on the treatment of tree seeds, the dependences of the completeness of the separation of the separated fraction on the specific load of the sieve, as well as on the speed of rotation of the drive shaft of the cleaning mechanism, were obtained. It is established that with an increase in the rotation frequency of the crank shaft of the cleaning mechanism, the completeness of the separation increases. It is determined that the greatest increase in the completeness of separation from 76.0% to 85.8% is observed when used in the design of the cleaning mechanism of gears with a diameter of 30 mm. It is established that the use of a mechanism for cleaning the holes of sieves, equipped with cylindrical working bodies, allows to increase the efficiency of the process of separating tree seeds.

Los estilos APA, Harvard, Vancouver, ISO, etc.

40

Suruthi, S., K. Sujatha y C. Menaka. "Size grading Standardization of sieve size for grading of barnyard millet (Echinochloa frumentacea L.) MDU-1". Journal of Applied and Natural Science 11, n.º 2 (10 de junio de 2019): 524–27. http://dx.doi.org/10.31018/jans.v11i2.2096.

Texto completo

Resumen

Seed grading is an important practice for better crop and also useful in separation of quality seeds in a seed lot. The aim of grading is to improve the uniformity of the seed lot by removing seeds of the same species with low quality. The present study was carried out to find out the optimum sieve size for size grading of seeds of barnyard millet (Echinochloa frumentacea L.) MDU1. The effect of seed size on physiological parameters were evaluated using BSS 10×10, BSS12×12 and BSS14×14 wire mesh sieves along with control. The barnyard millet seeds graded with BSS12×12 recorded higher seed recovery (76.67%) than other sieves used with required germination (92%), 1000 seed weight (3.9g), root length (14.1cm), shoot length (8.45cm), dry matter production (0.027g/10 seedlings) and vigour index (1983). Hence, seeds of barnyard millet MDU1 could be size graded using BSS12×12 sieve for more seed recovery with required seed quality standards as compared to BSS 10×10, BSS14×14 and ungraded seeds.

Los estilos APA, Harvard, Vancouver, ISO, etc.

41

Chambers, Nathanael, Taylor Cassidy, Bill McDowell y Steven Bethard. "Dense Event Ordering with a Multi-Pass Architecture". Transactions of the Association for Computational Linguistics 2 (diciembre de 2014): 273–84. http://dx.doi.org/10.1162/tacl_a_00182.

Texto completo

Resumen

The past 10 years of event ordering research has focused on learning partial orderings over document events and time expressions. The most popular corpus, the TimeBank, contains a small subset of the possible ordering graph. Many evaluations follow suit by only testing certain pairs of events (e.g., only main verbs of neighboring sentences). This has led most research to focus on specific learners for partial labelings. This paper attempts to nudge the discussion from identifying some relations to all relations. We present new experiments on strongly connected event graphs that contain ∼10 times more relations per document than the TimeBank. We also describe a shift away from the single learner to a sieve-based architecture that naturally blends multiple learners into a precision-ranked cascade of sieves. Each sieve adds labels to the event graph one at a time, and earlier sieves inform later ones through transitive closure. This paper thus describes innovations in both approach and task. We experiment on the densest event graphs to date and show a 14% gain over state-of-the-art.

Los estilos APA, Harvard, Vancouver, ISO, etc.

42

Dědeček, Jiří, Alena Vondrová y Jiří Čejka. "Catalytic Activity of Cu Ion-Exchanged Metalloaluminophosphates in NO Decomposition". Collection of Czechoslovak Chemical Communications 63, n.º 11 (1998): 1755–68. http://dx.doi.org/10.1135/cccc19981755.

Texto completo

Resumen

NO decomposition was investigated over Cu ion-exchanged aluminophosphate molecular sieve catalysts. Cu ions in cationic positions balanced by one framework negative charge in the metalloaluminophosphates of AlPO-5 and AlPO-11 structures exhibited catalytic activity in NO decomposition comparable with that of Cu-ZSM-5. No catalytic activity of the Cu ions incorporated during synthesis of molecular sieves into the framework in tetrahedral positions (CuAlPO-11) was observed. The catalytic activity of Cu-MeAlPO-5 and Cu-MeAlPO-11 was observed with various divalent metal ions of the MeAlPO-5 and MeAlPO-11 frameworks (Me = Zn, Mg, Fe, Co) and also with Cu exchanged SAPO-5 molecular sieves. The Cu-MeAlPO-5 and Cu-MeAlPO-11 catalysts differed only in the temperature of the maximum observed catalytic activity.

Los estilos APA, Harvard, Vancouver, ISO, etc.

43

Stark, C. R. y C. G. Chewning. "The effect of sieve agitators and dispersing agent on the method of determining and expressing fineness of feed materials by sieving". Animal Production Science 52, n.º 1 (2012): 69. http://dx.doi.org/10.1071/an11124.

Texto completo

Resumen

Research in both swine and poultry continue to investigate the optimal particle size for growth and gut health. Although researchers have reported the methods used to determine the particle size of the grain in a study, most reports have not provided details of the actual procedure. Although the standard method suggested adding both agitators and dispersing agents to facilitate the flow of material through the sieves there has been limited research as to whether these modifiers significantly change the particle size value. Researchers, laboratories, and feed mills that analyse samples without sieve agitators or a dispersing agent could overestimate the particle size and underestimate the distribution of the particles of a sample. Two experiments were conducted to determine the effect of adding sieve agitators and dispersing agent to the ANSI/ASAE S319.3 FEB03 ‘Method of Determining and Expressing Fineness of Feed Materials by Sieving’. The first experiment evaluated the effect of sieve agitator use and dispersing agent use on the geometric mean diameter (dgw) and geometric standard deviation (Sgw) of hammermill and roller mill corn samples. Whole corn was ground to produce samples that were classified as either coarse, medium, or fine. The second experiment evaluated the effect of sieve agitators, a dispersing agent, and the combination of agitators with a dispersing agent on dgw and Sgw of hammermill ground corn, wheat, and sorghum. The results of Expt 1 indicated that a decreased (P < 0.01) dgw resulted when agitators were added to the hammermill ground samples while a further decrease (P < 0.01) was observed due to the addition of the dispersing agent. The largest decrease in dgw was observed due to the addition of the dispersing agent. The addition of agitators to the roller mill samples only decreased the dgw of the medium grind sample. The dispersing agent decreased (P < 0.01) the dgw of roller mill samples. The addition of a dispersing agent consistently decreased the dgw of all the ground corn samples as compared with the standard method without modifiers. The results of Expt 2 were consistent with those of Expt 1 in that the addition of the dispersing agent and agitators decreased dgw values and appeared to have an additive effect in both corn and sorghum samples. The addition of a dispersing agent facilitated the flow of product through the sieves. The wider distribution (Sgw) indicated that a greater percentage of material flowed to the smaller sieves. The results of the experiments clearly showed the benefit of adding sieve agitators and a dispersing agent to facilitate the flow of material through the sieves, so that a better estimate of the micron diameter and particle size distribution could be achieved.

Los estilos APA, Harvard, Vancouver, ISO, etc.

44

Sivilevičius, Henrikas. "INFLUENCE OF HOMOGENEITY OF MINERAL MATERIALS' GRADING AND DOSING ERRORS ON THE STABILITY OF ASPHALT CONCRETE MIXTURE COMPOSITION". JOURNAL OF CIVIL ENGINEERING AND MANAGEMENT 9, n.º 1 (31 de marzo de 2003): 25–35. http://dx.doi.org/10.3846/13923730.2003.10531298.

Texto completo

Resumen

Errors of optimal composition asphalt concrete mixture designed in the laboratory and their importance for road construction are investigated. After the analysis of asphalt concrete production according to the traditional technology, factors influencing its structure, characteristics and quality are systematised. Mathematical models of dependence of medium quadratic deviations of siftings of finite dosed mineral materials through control sieves on the means of siftings are estimated by a regressive analysis. Variations of grading of hot fractions 0–5 mm and 5–15 mm as well as cold mineral powder sieved through technological sieves of mixing equipment and influence of errors of dosing these mineral materials in the produced mixture on the stability of quantity of containing mineral components (crushed stone, sand and mineral filler) are identified. The main trends of asphalt concrete structure and handling of its equipment methods improvement are presented.

Los estilos APA, Harvard, Vancouver, ISO, etc.

45

Mintova, Svetlana. "Nanosized Molecular Sieves". Collection of Czechoslovak Chemical Communications 68, n.º 10 (2003): 2032–54. http://dx.doi.org/10.1135/cccc20032032.

Texto completo

Resumen

Nanosized molecular sieves or colloidal zeolites are crystalline porous solids with particle sizes in the range of 10-1000 nm; they are synthesized from colloidal precursor solutions under hydrothermal conditions at temperatures lower than 100 °C. The complex mechanism by which nanosized microporous materials are assembling from framework constituent precursor species under heating is investigated by in situ dynamic light scattering, X-ray diffraction using synchrotron radiation, high resolution transmission electron microscopy, and IR/Raman spectroscopies. The development of new crystallization methods that allow the fabrication of zeolites in forms suitable for practical utilization, such as thin films, layers, and monoliths based on the seed method and spin coating approach is discussed. In situ X-ray measurements of zeolite crystal growth simultaneously in solutions and films are performed, in which near surface depth-sensitive grazing incidence diffraction is combined with the in situ growth of thin zeolite films that is ideally suited to shed light on the unresolved mechanisms of self-organized channel orientation for various zeolite systems. In addition, the nanosized Faujasite (FAU) zeolite was employed as host for the stabilization of guest molecules such as 2-(2'-hydroxyphenyl)benzothiazole (HBT); the trans keto tautomer of HBT inside the FAU zeolite is demonstrated and compared with the cis keto tautomer formed in ethanolic solution.

Los estilos APA, Harvard, Vancouver, ISO, etc.

46

Maheswari, R., K. Shanthi, T. Sivakumar y Sankarasubbier Narayanan. "Mesoporous molecular sieves". Applied Catalysis A: General 245, n.º 2 (junio de 2003): 221–30. http://dx.doi.org/10.1016/s0926-860x(02)00642-7.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

47

Guerra, Gaetano, Giuseppe Milano, Vincenzo Venditto, Pellegrino Musto, Claudio De Rosa y Luigi Cavallo. "Thermoplastic Molecular Sieves". Chemistry of Materials 12, n.º 2 (febrero de 2000): 363–68. http://dx.doi.org/10.1021/cm991064f.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

48

Szabo, Tomas, Brendan M. O'Leary y Julius Rebek, Jr. "Self-Assembling Sieves". Angewandte Chemie International Edition 37, n.º 24 (31 de diciembre de 1998): 3410–13. http://dx.doi.org/10.1002/(sici)1521-3773(19981231)37:24<3410::aid-anie3410>3.0.co;2-1.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

49

Goldberg, Israel. "Metalloporphyrin Molecular Sieves". Chemistry – A European Journal 6, n.º 21 (13 de octubre de 2000): 3863–70. http://dx.doi.org/10.1002/1521-3765(20001103)6:21<3863::aid-chem3863>3.0.co;2-v.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

50

Goldberg, Israel. "Metalloporphyrin Molecular Sieves". Chemistry 6, n.º 21 (3 de noviembre de 2000): 3863–70. http://dx.doi.org/10.1002/1521-3765(20001103)6:21<3863::aid-chem3863>3.3.co;2-m.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

Artículos de revistas sobre el tema "Sieves"

Crea una cita precisa en los estilos APA, MLA, Chicago, Harvard y otros