scholarly journals Long Term and Large-Scale Continuous Studies on Zinc(II) Sorption and Desorption on Hybrid Pectin-Guar Gum Biosorbent

Polymers ◽  
2019 ◽  
Vol 11 (1) ◽  
pp. 96 ◽  
Author(s):  
Agata Jakóbik-Kolon ◽  
Joanna Bok-Badura ◽  
Andrzej Milewski ◽  
Krzysztof Karoń
Keyword(s):  
Flow Rate ◽  
Large Scale ◽  
Guar Gum ◽  
Mechanical Stability ◽  
Small Scale ◽  
Time Model ◽  
Fine Grain ◽  
Real Wastewater ◽  
Scale Experiment ◽  
Large Scale Tests

Pectin-guar gum biosorbent was tested for zinc(II) ions removal in column process. Sorption–desorption experiments were performed in laboratory and at larger scale. The breakthrough and elution curves were obtained for various conditions. The Bed Depth Service Time model was tested for utility in data estimation. Possibility of sorbent reuse and its lifetime was examined in 20 repeated sorption–desorption cycles. Finally, tests were repeated for real wastewater from galvanizing plant, giving satisfactory results. The effectiveness of Zn(II) sorption happened to be dependent on process parameters; tests have proved that it increased with increasing bed height and with decreasing flow rate or grain size. For an initial zinc concentration of 30 mg/L, even 2096 mL of zinc solution could be purified in small scale experiment (2 g of fine grain sorbent and flow rate 60 mL/h) or 5900 L in large-scale (16 kg of large grain sorbent and flow rate 45 L/h). This allowed for 40-fold or 49-fold zinc increases in concentration in one sorption–desorption cycle. The most successful results are meant that at least 20 sorption–desorption cycles could be performed on one portion of biosorbent without loss of its effectiveness, large-scale tests for real wastewater from galvanizing plant gave satisfactory results, and that the form and mechanical stability of our sorbent is suitable for column usage with flow rates applicable in industry.

scholarly journals LARGE AND SMALL SCALE WAVE OVERTOPPING MEASUREMENTS FOR AFSLUITDIJK REHABILITATION PROJECT

2020 ◽  
pp. 15
Author(s):  
Wouter Ockeloen ◽  
Coen Kuiper ◽  
Sjoerd van den Steen
Keyword(s):  
Water Management ◽  
Physical Model ◽  
Large Scale ◽  
Wadden Sea ◽  
Model Tests ◽  
Small Scale ◽  
Water Safety ◽  
Wave Overtopping ◽  
Physical Model Tests ◽  
Large Scale Tests

The 'Afsluitdijk' is a 32 km enclosure dam which separates the Wadden sea and the Lake IJssel. The dam currently undergoes a major rehabilitation to meet the requirements with regard to water safety. The Dutch Ministry of infrastructure and Water Management (Rijkswaterstaat division) has commissioned Levvel, a consortium of BAM, Van Oord and Rebel, to prepare the design and carry out the reconstruction of the dam including sluices and highway. The project includes reinforcement of the armour layers and wave overtopping reduction. As part of the contract Rijkswaterstaat prescribed the contractor (Levvel) to verify the design with large scale physical model tests (min. 1:3 scale). These tests were carried out in the Delta Flume of Deltares. Prior to the large scale tests, smaller scale tests (1:20) have been carried out to optimize the design with regard to armour stability and wave overtopping. The research described here focuses on the wave overtopping.Recorded Presentation from the vICCE (YouTube Link): https://youtu.be/kPga0wVCCIE

INVESTIGATING EXPLOSIVE SENSITIVITY TO ELECTROSTATIC DISCHARGE ACCORDING TO NATO STANDARDIZATION DOCUMENTS

2016 ◽  
pp. 39-60
Author(s):  
Maciej MISZCZAK, ◽  
Cezary Kwiecień ◽  
Sławomir Gryka
Keyword(s):  
Large Scale ◽  
Small Scale ◽  
Rocket Propellants ◽  
Smokeless Powders ◽  
Solid Explosives ◽  
Solid Rocket ◽  
Susceptibility Tests ◽  
Explosive Sensitivity ◽  
Solid Rocket Propellants ◽  
Large Scale Tests

Some small scale methods for testing the sensitivity against ESD (Electro Static Discharge) of solid explosives like primary explosives, booster explosives, high explosives, gun and rocket propellants (smokeless powders and solid rocket propellants) and pyrotechnic compositions are overviewed in the paper from the point of NATO standardisation documentation that includes Standard Agreement (STANAG) 4490 [1], Allied Ordnance Publication AOP-7 [2] and STANAG 4170 [3]. The overview is supplemented with analyses and assessments of methods and received results. ESD sensitivity tests of explosives in small scale have not been unified yet in NATO standardization documentation in contradiction to NATO large scale tests. Such unification would be beneficial as it could lead to a greater reliability of results of explosive ESD susceptibility tests performed e.g. in the frame of interlaboratory tests.

scholarly journals PENGEMBANGAN KONSTRUK INSTRUMEN HASIL PEMBELAJARAN PRAKTIK KARAWITAN JAWA

2014 ◽  
Vol 18 (2) ◽  
pp. 168-187
Author(s):  
Budi Raharja ◽  
Suminto A. Sayuti
Keyword(s):  
Data Analysis ◽  
Focus Group ◽  
Product Development ◽  
Correlation Coefficient ◽  
Large Scale ◽  
Group Discussion ◽  
Small Scale ◽  
Fitness Test ◽  
Content Factor ◽  
Large Scale Tests

Penelitian ini mengembangkan instrumen hasil pembelajaran praktik karawitan Jawa dari perspektif  keterampilan dan sikap. Perspektif keterampilan menilai kemampuan peserta didik menyelaraskan komponen pembelajaran (melodi, irama/tempo, dan bunyi/nada); sedangkan perspektif sikap menilai pemahaman, penghayatan, dan pengamalan komponen pembelajaran tersebut. Langkah-langkahnya meliputi pengembangan produk, validasi produk, implementasi produk, dan analisis data. Pengembangan produk meliputi pengembangan instrumen keterampilan dan pengembangan instrumen sikap; validasi produk menguji produk dalam diskusi kelompok terfokus, seminar instrumen, dan validasi ahli; implementasi produk adalah mengaplikasikan instrumen dalam uji coba skala kecil dan skala besar serta uji coba utama; sedangkan analisis datanya menggunakan uji kecocokan model. Hasil uji kecocokan model menyatakan bahwa model dinyatakan fit dengan koefisien korelasi antara 0,90 hingga 0,98 dan muatan faktor antara 0,62 hingga 0,91. Instrumen menghasilkan informasi kemampuan menyelaraskan melodi, irama, dan bunyi ricikan serta karakteristik tabuhan peserta didik dari perspektif dan pemahaman, penghayatan, dan pengamalan komponen pembelajarannya. Kata kunci: karawitan, penilaian, keterampilan, sikap _____________________________________________________________ DEVELOPING AN INSTRUMENT CONSTRUCT FOR ASSESSING THE JAVANESE KARAWITAN LEARNING OUTCOMEAbstract This study developed an instrument for assessing learning achievement of Javanese karawitan practice from the perspectives of skill and attitude. The skill perspective evaluates the students’ ability to harmonize the learning components (melody, rhythm/tempo, and sound/tone); while the attitude perspective evaluates their understanding, comprehension, and application of those learning components. The steps in doing the research include product development, product validation, product implementation, and data analysis. Product development includes developing the skill instruments and developing the attitude instruments; while product validation includes testing the product in focus group discussion, seminar for the instruments, and expert judgment. Product implementation is applying the instrument in small-scale and large-scale tests as well as main testing, while the data analysis used model fitness test. The result of model fitness test shows that this model is fit with correlation coefficient from 0.90 to 0.98 and content factor from 0.62 to 0.91. The instrument has yielded information concerning the ability of students to harmonize melody, rhythm, and the ricikan and tabuhan sounds from the perspectives of understanding, comprehending, and applying the learning components.Keywords: karawitan, assessment, skill, and attitude

scholarly journals Developing STEM-based TGT learning model to improve students' process skills

2020 ◽  
Vol 6 (3) ◽  
Author(s):  
Faizah Firdaus ◽  
Wachju Subchan ◽  
Erlia Narulita
Keyword(s):  
Research And Development ◽  
21St Century ◽  
Large Scale ◽  
Learning Model ◽  
Small Scale ◽  
Process Skills ◽  
Learning Models ◽  
Science Process Skills ◽  
Team Games ◽  
Large Scale Tests

Strengthening STEM-oriented learning is necessary for 21st century, so the development of appropriate learning models must be carried out. The aimed to of this study were analized validity, effectiveness, and practicality of STEM-based Team Games and Tournament (TGT) learning model towards the students' science process skills. This research was research and development (R&D) with a 4-D development namely; Defining, Designing, Developing, and Disseminating. The study involved 2 experts as validators, 2 teachers as user, and 112 students in small-scale tests, large-scale tests, and distribution tests in SMA. The research was done until the stage of disseminating and produced. The results showed the validity value of 83% was categorized as very valid, the effectiveness score of 83.9% was categorized as good, and the practicality score was 87.5%, so that it was declared valid, effective, and practical to improve the science process skills. Therefore, it is recommended to be applied in schools.

scholarly journals The role of the sonic scale in the growth of magnetic field in compressible turbulence

2020 ◽  
Vol 493 (3) ◽  
pp. 4400-4408
Author(s):  
Itzhak Fouxon ◽  
Michael Mond
Keyword(s):  
Magnetic Field ◽  
Growth Rate ◽  
Large Scale ◽  
Compressible Turbulence ◽  
Small Scale ◽  
Integral Scale ◽  
Time Model ◽  
Turbulent Eddies ◽  
Field Amplification ◽  
The Magnetic Field

ABSTRACT We study the growth of small fluctuations of magnetic field in supersonic turbulence, the small-scale dynamo. The growth is due to the smallest and fastest turbulent eddies above the resistive scale. We observe that for supersonic turbulence these eddies are localized below the sonic scale ls, defined as the scale where the typical velocity of the turbulent eddies equals the speed of sound, and are therefore effectively incompressible. All previous studies have ignored the existence of the sonic scale and consequently treated the entire inertial range as made up of compressible eddies. However, at large Mach numbers ls is much smaller than the integral scale of the turbulence so the fastest growing mode of the magnetic field belongs to small-scale incompressible turbulence. We determine this mode and the associated growth rate numerically with the aid of a white noise in time model of turbulence whose approximate validity for the description of the Navier–Stokes turbulence is explained. For that purpose, we introduce a new non-dimensional number Rsm that we name the magnetosonic Reynolds number that describes the division of the magnetic field amplification range between small-scale incompressible eddies and large-scale supersonic ones. We show that indeed, as Rsm grows (which means that the incompressible eddies occupy a larger portion of the magnetic field amplification range) the growth rate of the fastest growing mode increases, while the spatial distribution of the growing magnetic field shifts to smaller scales. Our result implies the existence of small-scale dynamo for compressible homogeneous turbulence.

Shear Tests of Composite Slabs, Experimental and Numerical Investigation

2014 ◽  
Vol 923 ◽  
pp. 217-220 ◽  
Author(s):  
Josef Holomek ◽  
Miroslav Bajer ◽  
Jan Barnat ◽  
Martin Vild
Keyword(s):  
Large Scale ◽  
Small Scale ◽  
Concrete Slabs ◽  
Shear Tests ◽  
Composite Action ◽  
Permanent Formwork ◽  
Composite Slabs ◽  
New Type ◽  
Large Scale Tests ◽  
Scale Shear

Composite slab is being used for horizontal structures. The sheeting can serve as a permanent formwork and no additional reinforcement can be required. The slabs are then fast and easy assemble construction which can be effectively used in reconstructions. One of the meanings to assure composite action of composite steel-concrete slabs is prepressed embossments. Its main disadvantage is that the design of a new type of sheeting requires expensive and time consuming large-scale laboratory testing which hamper its widespread commercial usage. Small-scale shear tests present a less expensive alternative to the large-scale tests but its results cannot be simply used for the design of the whole slab. The results from small-scale tests with different options are compared in this paper. Also a possibility of contribution of FE simulation results to the small-scale tests usage is investigated.

Large-scale tests to investigate MgO concrete with a long-term stable 3-1-8 phase in the Sondershausen and Teutschenthal mines

2020 ◽  
Author(s):  
Jan Aurich ◽  
Daniela Freyer ◽  
Matthias Gruner ◽  
Wolfram Kudla
Keyword(s):  
Large Scale ◽  
Salt Mine ◽  
Binding Reaction ◽  
Scale Experiment ◽  
One Year ◽  
Mgo Concrete ◽  
Large Scale Tests ◽  
Sealing Elements ◽  
Vertical Borehole

<p>These abstract bases on the R & D project ELSA Phase II - Concept development for shaft seals and testing of sealing elements for HAW repositories, funded by the German Federal Ministry of Energy and Economic Affairs.</p><p>The installation of sealing elements in salt rock requires a mechanical support system, which is chemical compatible with the host rock. In future HAW-repositories abutments and sealing elements within the shafts and drifts could be made of magnesia building material with the long term stable 3-1-8 binder phase, if solution containing magnesium can attack the seal.</p><p>In 2014 a first large-scale experiment was performed in the Sondershausen salt mine in Germany. A vertical borehole with the depth of two meters and a diameter of 1.1 meter was filled with the magnesia-based concrete. Several sensors measured the development of temperature, comprehensive stress and expansion within the test construction for approximately one year. During the binding reaction the temperature increased by 55 K in the center. After 150 days, the expansion in axial direction reached 2.4 mm/m and 1.1 mm/m in radial direction.</p><p>In 2018 a second large-scale-experiment was performed in the Teutschenthal salt mine, Germany to continue the investigations. A new vertical borehole with the depth of 3.5 meters and a diameter of 1.3 meters was filled with the same material. The temperature in the center increased by 40 K during the binding reaction and decreased down to the ambient temperature after 20 days. In result of the first experiences, the stress sensor range was increased. After one year a comprehensive stress of 6.2 MPa was measured at the contour and is still evolving at this point (early 2020). The maximum axial expansion reached 7.9 mm/m and stays at this level. The maximum radial expansion reached 0.7 mm/m 20 days after concreting and decreased subsequently. This material behavior corresponds to the high comprehensive stress level.</p><p>The second experiment is equipped with a pressure chamber at the bottom. A first determination of the integral gas permeability revealed a value of approx. 3E<sup>-18 </sup>m² to 3E<sup>-17 </sup>m². In the near term a multistage pressurization of the construction is planned, using a saturated NaCl solution to evaluate the sealing ability.</p><p>This contribution reports on the measured parameters (temperature, stress, strain) of the two large-scale tests with long-term stable MgO-concrete and the composition requirements to obtain a long-term stable MgO concrete. Long-term stable MgO concrete with 3-1-8 phase has been used for the first time in these tests. The measured test-results are the foundation for modelling the behaviour of the MgO-concrete.</p>

scholarly journals A Model for Igniter Mass Flow Rate History Evaluation for Solid Rocket Motors

2019 ◽  
Vol 2019 ◽  
pp. 1-12
Author(s):  
Yanjie Ma ◽  
Futing Bao ◽  
Weihua Hui ◽  
Yang Liu ◽  
Yijie Gao
Keyword(s):  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Large Scale ◽  
Rocket Motor ◽  
Small Scale ◽  
Solid Rocket Motor ◽  
Combustion Gas ◽  
Proposed Model ◽  
Solid Rocket

This paper describes a zero-dimensional model for evaluating the mass flow rate history of a solid rocket motor igniter. Based on the results of an igniter-firing experiment, in which the igniter is the only source of combustion gas and no propellant is ignited, the proposed model can be used to compute the mass flow rate of the igniter. Different species and temperature-dependent properties, such as the specific heat for each species, are considered. The coupling between the flow field variables in the combustion chamber and the heat transfer at the gas-solid interface is computed in a segment way. Calculations are performed for different species and properties, and the errors are discussed. Using the computed igniter mass flow rate as a boundary condition, a two-dimensional calculation is performed for validation purposes. The results are in good agreement with experimental data. The proposed model can be used to provide reasonable boundary conditions for solid rocket motor simulations and to evaluate the performance of igniters. Although derived on the basis of a small-scale solid rocket motor, the model has the potential to be used in large-scale systems.

scholarly journals Vitrification of High-Level Radioactive Waste in a Small-Scale Joule-Heated Ceramic Melter

1981 ◽  
Vol 6 ◽  
Author(s):  
Gerald B. Woolsey ◽  
M. John Plodinec
Keyword(s):  
Radioactive Waste ◽  
Large Scale ◽  
Liquid Waste ◽  
Glass Frit ◽  
Small Scale ◽  
Savannah River ◽  
Savannah River Plant ◽  
Reference Process ◽  
High Level ◽  
Large Scale Tests

ABSTRACTVitrification is the reference process for the immobilization of radioactive waste from the production of defense materials at the Savannah River Plant (SRP). Since 1979, a small vitrification facility (1 Ib/hr) has been operated at the Savannah River Laboratory using actual SRP waste. In previous studies. dried waste was fed to this smaller melter. This report discusses direct feeding of actual liquid-waste slurries to the small melter. These liquidfeeding tests demonstrated that addition of premelted glass frit to the waste slurry reduces the amount of material volatilized. Results of these tests are in accord with results of large-scale tests with actual waste.

scholarly journals LARGE VERIFICATION TESTS ON ROCK SLOPE STABILITY

1988 ◽  
Vol 1 (21) ◽  
pp. 157
Author(s):  
J.W. Van der Meer ◽  
K.W. Pilarczyk
Keyword(s):  
Large Scale ◽  
Scale Effects ◽  
Rock Slope Stability ◽  
Small Scale ◽  
Rock Slopes ◽  
Ripple Formation ◽  
Scale Test ◽  
Gravel Beaches ◽  
The Stability ◽  
Large Scale Tests

A number of large scale tests on stability of rock slopes and gravel beaches is described and compared with small scale test results. The following topics are treated: the stability of a rock armour layer, the profile formation of a berm breakwater, the profile formation of gravel beaches, including ripple formation, and reflection and overtopping on rock slopes. The general conclusion is that scale effects could not be found.

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