Wyniki wyszukiwania - Biblioteka Nauki

1

Changes of feed bulk density during drum granulation of bentonite

100%

Heim A. , Obraniak A. , Gluba T.

Physicochemical Problems of Mineral Processing

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2005

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tom Vol. 39

219-228

EN

Results of investigations on bentonite agglomeration in drum granulators of diameter D = 0.25- 0.4 m, with drop-wise wetting are discussed. The effect of process and equipment parameters (drum diameter D, filling factor of the drum k, granulation time t, moisture content w, rotational speed of the drum) on bulk density of a bed ń has been determined.

PL

Przedstawiono wyniki badań aglomeracji bentonitu w granulatorach bębnowych o średnicy D=0.25- 0.4m, przy nawilżaniu kroplowym. Określono wpływ parametrów procesowo-aparaturowych (średnicy bębna D, stopnia wypełnienia bębna k, czasu granulacji t, wilgotności w, prędkości obrotowej aparatu) na gęstość nasypową złoża.

2

Impact of agricultural use on chosen soil properties

100%

Braun B.

Miscellanea Geographica. Regional Studies on Development

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2008

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tom 13

153-162

EN

Agricultural use may change soil. These changes may be observed by examining certain soil properties. In numerous cases of agricultural use, soil compaction may be observed at the depth of 25-35 cm. After many years of use, this may lead to the creation of a plough sole. On arable grounds, which are generally fertilized by minerals, a decrease in organic matter content and soil acidification are frequently observed. Each human activity leads to changes in the natural environment. In the case of agricultural use, the greatest changes take place in soil. Mechanization in agriculture and the wish to produce ever-greater amounts of crops influence changes in some soil properties. In a short time, changes in soil reaction, organic matter content or creation of a plough sole at the depth of 25-35 cm may observed.

3

Development of pedotransfer functions for predicting soil bulk density : a case study in Indonesian small island

100%

Yanti E. D. , Mulyono A. , Djuwansah M. R. , Narulita I. , Putra R. D. , Surinati D.

Journal of Water and Land Development

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2021

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tom no. 51

181--187

EN

Unlike many other countries, tropical regions such as Indonesia still lack publications on pedotransfer functions (PTFs), particularly ones dedicated to the predicting of soil bulk density. Soil bulk density affects soil density, porosity, water holding capacity, drainage, and the stock and flux of nutrients in the soil. However, obtaining access to a laboratory is difficult, time-consuming, and costly. Therefore, it is necessary to utilise PTFs to estimate soil bulk density. This study aims to define soil properties related to soil bulk density, develop new PTFs using multiple linear regression (MLR), and evaluate the performance and accuracy of PTFs (new and existing). Seven existing PTFs were applied in this study. For the purposes of evaluation, Pearson’s correlation (r), mean error (ME), root mean square error (RMSE), and modelling efficiency (EF) were used. The study was conducted in five soil types on Bintan Island, Indonesia. Soil depth and organic carbon (SOC) are soil properties potentially relevant for soil bulk density prediction. The ME, RMSE, and EF values were lower for the newly developed PTFs than for existing PTFs. In summary, we concluded that the newly developed PTFs have higher accuracy than existing PTFs derived from literature. The prediction of soil bulk density will be more accurate if PTFs are applied directly in the area that is to be studied.

4

Wpływ parametrów procesu wytwarzania tripolifosforanu sodu na jego gęstość nasypową

100%

Banach M. , Wzorek Z. , Gorazda K.

Przemysł Chemiczny

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2010

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tom T. 89, nr 4

286-288

5

Zwiększanie gęstości nasypowej tripolifosforanu sodu metodą chemiczną

100%

Gorazda K. , Banach M. , Makara A. , Wzorek Z.

Przemysł Chemiczny

|

2010

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tom T. 89, nr 4

356-358

6

Statystyczna analiza wyników badań otrzymywania tripolifosforanu sodu o podwyższonej gęstości nasypowej

100%

Banach M. , Wzorek Z. , Gorazda K.

Przemysł Chemiczny

|

2010

|

tom T. 89, nr 4

282-285

7

Bulk density of forest energy chips

100%

Gendek A. , Aniszewska M. , Chwedoruk K.

Annals of Warsaw University of Life Sciences - SGGW. Agriculture

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2016

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nr 67

8

Conductivity studies in mixed alkali vanadotellurite glasses

88%

Kumar M. P. , Sankarappa T.

Materials Science Poland

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2008

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tom Vol. 26, No. 3

647--657

EN

A set of novel mixed alkali vanadotellurite glasses (V2O5)0.25(Li2O)0.25(K2O)x(TeO2)1.x (0.05 . x . 0.30) have been investigated for density and dc conductivity in the temperature range from 380 K to 480 K. The density exhibited a minimum, and molar volume showed a maximum at x = 0.20. Conductivity data have been analyzed in the light of Mott�fs small polaron hopping model and high temperature activation energy values have been determined. The conductivity and activation energy also passed through a minimum and maximum, respectively, at x = 0.20. This result has been attributed to the mixed alkali effect. The strength of mixed alkali effect has been estimated. It is for the first time that vanadotellurite glasses are shown to exhibit mixed alkali effect. Various physical and polaron hopping parameters have been determined and discussed.

9

Plough sole as the result of the agricultural land use

88%

Stojek B.

|

tom 11

63-69

EN

The purpose of this paper was the estimate of the substratum compaction in various soil types and under various conditions of use. The compaction characteristics were performed on the basis of bulk density of soil. It was performed on various types of soil, built of various materials, occurring in the vicinity of Płock. The soils are farming land. The greatest substratum compaction was observed in arable lands, built of light loam, silt and loamy sand. The difference in bulk density between the layer at the depth of 25 - 35 cm and the adjacent horizons reaches 0.3 Mg per cubic metre. In soils used for green crops the substratum layer does not show a large difference between the adjacent layers, but the values of bulk density are equal to about 1.6 - 1.8 Mg per cubic metre already near the surface. Higher values of bulk density at the depth of 25 - 35 cm were observed in 68% of soils under investigation.

10

Physicochemical properties of spray dried honey preparations

88%

Samborska K. , Bienkowska B.

Zeszyty Problemowe Postępów Nauk Rolniczych

|

2013

|

tom 575

EN

The aim of work was to characterise the physical and chemical properties of spray dried honey preparations and the changes in these properties during storage. Spray drying was performed at inlet air temperature 160 and 200°C, atomising disk speed 32 000 and 38 000 rpm, with the use of two types of carriers: dextrin and maltodextrin. The resulting powders had the desirable physical properties: low water content and activity, complete solubility and low cohesiveness. The powders produced with the use of dextrin had higher hygroscopicity and poorer solubility, they were also characterised by the highest water absorption during storage. Powders obtained with the use of reduced atomisation speed were the most stable in terms of water absorption and the changes of hygroscopicity during storage. Solubility of all powders was stable during storage.

PL

Celem pracy było określenie właściwości ﬁzycznych i chemicznych preparatów miodowych suszonych rozpyłowo oraz zmiany tych właściwości w czasie przechowywania. Suszenie rozpyłowe przeprowadzono przy temperaturze powietrza wlotowego 160 do 200°C, szybkość obrotowa dysku rozpylającego wynosiła 32 000 i 38 000 obrotów na minutę, użyto dwóch rodzajów nośników: dekstrynę i maltodekstrynę. Otrzymane proszki miały pożądane właściwości ﬁzyczne: niską zawartość i aktywność wody, całkowitą rozpuszczalność i niską spójność. Proszki wytworzone z wykorzystaniem dekstryny miały wyższą higroskopijność i gorszą rozpuszczalność, charakteryzowały się najwyższą ilością wchłoniętej wody w czasie przechowywania. Proszki otrzymane z wykorzystaniem zmniejszonej szybkości obrotowej dysku rozpylającego były bardziej stabilne pod względem absorpcji wody i zmiany higroskopijności podczas przechowywania. Rozpuszczalność wszystkich proszków była stabilna w czasie przechowywania.

11

Damping Properties and Density of Helmet Liners Made of Expanded Polystyrene (EPS)

88%

Trzaskalska M. , Chwastek R.

Archives of Metallurgy and Materials

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2021

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tom Vol. 66, iss. 1

339--344

EN

The purpose of the work was to determine the infuence of the bulk density ρz of granules, processing parameters and the density of ski inserts ρw made of expanded polystyrene (EPS) on their damping properties. For this aim liners for ski helmets with 3 different bulk densities were made. Sintering time and sintering pressure were also changed. The percentage damping factor η was determined on the basis of the results obtained in the rebound resilience test. Based on the analysis of the obtained data, it was found that increasing the density of EPS pads ρw increases their damping properties and at the same time contributes to a decrease in elasticity, increase in hardness and brittleness of EPS products.

12

A change in the properties of the bed during drum granulation of silica flour

88%

Heim A. , Gluba T. , Obraniak A. , Gawot-Młynarczyk E. , Błaszczyk M.

Polish Journal of Chemical Technology

|

2006

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tom Vol. 8, nr 4

11-13

EN

The article presents the investigations of the changes in the bulk density and the angle of the natural repose of the bed in the process of wet granulation of silica flour in the drum granulator of periodical operation. The variable parameters of wetting include the moisture content, droplet diameter, and the surface tension of the wetting liquid. The distilled water with the Rokanol L4P5 surfactant was used as a wetting liquid.

13

Calculating particle density, bulk density, and total porosity of soil based on its texture

75%

Brogowski Z. , Kwasowski W. , Madymiak R.

Soil Science Annual

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2014

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tom 65

|

nr 4

14

Precipitation of calcium carbonate in the presence of urea at 293K

75%

Białowicz K. , Kiełkowska U. , Trypuć M.

Polish Journal of Chemical Technology

|

2008

|

tom 10

|

nr 4

7-10

EN

The results of the precipitation of calcium carbonate from waste distillation liquor (DS) from the Solvay method and sodium bicarbonate saturated solution in the presence of urea were presented. The investigation was carried out at 293K. The influence of the time of reagents dosage to the solution of urea on the physicochemical character of obtaining product was studied. The time of reagents dosage: 1, 5, 10, 20, 30 min and the concentration of the urea applied: 0.5, 1, 2 and 4 mol/dm3. The granulometric composition, the values of bulk and packing densities and the absorptiveness sorption of water and paraffin oil of the obtaining calcium carbonate were investigated.

15

Spoil heaps - influence of ash and bulk weight

75%

Kvietkova M. , Gasparik M. , Slavik M. , Ruman D. , Cafourek J.

Annals of Warsaw University of Life Sciences - SGGW. Forestry and Wood Technology

|

2015

|

tom 92

16

Effect of soil bulk density on forest tree seedlings

75%

Kormanek M. , Banach J. , Sowa P.

|

tom 29

|

nr 1

EN

The paper presents the results of an analysis of the influence of soil bulk density in a forest nursery plot on the growth and quality parameters of Scots pine and European beech seedlings. Particular density variants were obtained using a tractor device exerting controlled pressure on the soil, while field examinations were performed on an area of ‘Kłaj’ forest nursery in Niepołomice Forest District. Three series of plots were prepared for each species, applying a unit pressure of the values of 50, 100, 150, 200, 250 kPa, corresponding to the dry bulk density in the range of 1.03-1.19 g cm-3, and control plots without the pressure. Seeds of the examined species were sown on the prepared plots, and after 6 months of growth the seedlings were subjected to biometric analysis determining differentiation in root neck diameter, length of the above-ground part and root system, as well as dry mass of particular parts of the plant. The quality of the seedlings was also determined using the method of Schmidt-Vogt. The results obtained show that the change in dry bulk densitysoil significantly affected most of the growth parameters of theexamined seedlings. Especially high negative correlations were obtained for the length and dry mass of the root system. A significant influence of dry bulk density variant on all growth parameters of Scots pine seedlings, and on some parameters of European beech was demonstrated. An increase in soil bulk density clearly caused also a deterioration of European beech seedlings quality.

17

Model prędkościowy fal P i S oraz gęstości objętościowych dla wybranych otworów w rejonie Karpat Zachodnich

75%

Bała M. , Witek K.

Geologia / Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie

|

2007

|

tom T. 33, z. 4/1

59-80

PL

Zostały obliczone parametry sprężyste - prędkości fal podłużnych i poprzecznych, ich stosunki oraz gęstości objętościowe dla zróżnicowanych poziomów litostratygraficznych w wybranych otworach z rejonu Karpat Zachodnich. Do obliczeń wykorzystano program komputerowy Estymacja opracowany przez M. Bałę i A. Cichego w ramach projektu badawczego nr 8 T12B 046 20. Zastosowano teoretyczny model Biota-Gassmanna, pozwalający na wyznaczanie wspomnianych parametrów na podstawie znajomości dokładnego składu mineralnego skał, współczynników porowatości i nasycenia wodą i węglowodorami, które można uzyskać z interpretacji ilościowej profilowań geofizyki otworowej. Przeprowadzono zestawienia średnich wartości obliczonych parametrów w wydzielonych jednostkach stratygraficznych, co posłużyło do oceny modelu prędkości i gęstości objętościowej.

EN

Elastic parameters including P-wave and S-wave velocities, their ratios, and bulk density for different lithostratigraphic levels were calculated for selected boreholes from the Western Carpathians. The calculations were made with the use of the Estymacja computer program written by M. Bała and A. Cichy within the research project No. 8 T12B 046 20. The theoretical Biot--Gasstnann's model was used, which enabled the above mentioned parameters to be determined based on known mineral composition, porosity, and water- and hydrocarbon saturation of rocks, which can be obtained from well log quantitative interpretation. Mean values of the parameters were put together for selected stratigraphic units and used for the evaluation of velocity model and bulk density model.

18

Optimization of Packing Density of M30 Concrete with Steel Slag as Coarse Aggregate Using Fuzzy Logic

75%

Arivoli M. , Malathy R.

Archives of Metallurgy and Materials

|

2017

|

tom Vol. 62, iss. 3

1903--1913

EN

Concrete plays a vital role in the design and construction of the infrastructure. To meet the global demand of concrete in future, it is becoming a challenging task to find suitable alternatives to natural aggregates. Steel slag is a by-product of steel making process. The steel slag aggregates are characterized by studying particle size and shape, physical and chemical properties, and mechanical properties as per IS: 2386-1963. The characterization study reveals the better performance of steel slag aggregate over natural coarse aggregate. M30 grade of concrete is designed and natural coarse aggregate is completely replaced by steel slag aggregate. Packing density of aggregates affects the characteristics of concrete. The present paper proposes a fuzzy system for concrete mix proportioning which increases the packing density. The proposed fuzzy system have four sub fuzzy system to arrive compressive strength, water cement ratio, ideal grading curve and free water content for concrete mix proportioning. The results show, the concrete mix proportion of the given fuzzy model agrees with IS method. The comparison of results shows that both proposed fuzzy system and IS method, there is a remarkable increase in compressive strength and bulk density, with increment in the percentage replacement of steel slag.

19

Uncertainty of measurement of bulk and shaken density of Pulgran and Salmag

75%

Nowak J. , Przystupa W. , Krawczuk A.

Agricultural Engineering

|

2020

|

tom Vol. 24, No. 3

73--81

EN

The article presents results of research on the bulk and shaken density of two commercial fertilizers: Pulgran urea and universal nitrogen fertilizer Salmag. A statistical analysis of the obtained results of average density at the assumed level of significance proved a significant difference between shaken and bulk density investigated with the use of Engelsmann apparatus and shaken density tested with a laboratory shaker for both investigated fertilizers. The obtained test results and uncertainty of the measured values served for calculation of uncertainty of the standard complex bulk and shaken density determined in case of many uncertainties. Further, an analysis of the impact of error sources on the value of complex uncertainty was conducted. The final results of the measurement were presented according to the convention of the Central Office of Measures.

PL

W artykule zaprezentowano wyniki badań gęstości nasypowej i utrzęsionej dwóch komercyjnych nawozów: mocznika Pulgranu i uniwersalnego nawozu azotowego Salmagu. Przeprowadzona analiza statystyczna otrzymanych wyników średnich gęstości na założonym poziomie istotności, wykazała istotne różnicę między gęstością utrzęsioną oraz nasypową badaną przy zastosowaniu aparatu Engelsmana, jak również gęstością utrzęsioną badaną z wykorzystaniem wytrząsarki laboratoryjnej dla obu badanych nawozów. Uzyskane wyniki badań oraz niepewności mierzonych wielkości posłużyły do obliczenia niepewność standardowej złożonej gęstości nasypowej i utrzęsionej wyznaczanej w przypadku występowania wielu niepewności. W dalszej części pracy przeprowadzono analizę wpływu źródeł błędów na wartość niepewności złożonej. Końcowe wyniki pomiaru przedstawiono według konwencji Głównego Urzędu Miar.

20

Wpływ aglomeracji w mechanicznie generowanym złożu fluidalnym na gęstość i porowatość modelowej żywności w proszku

75%

Domian E. , Burdzanowska D.

Inżynieria Rolnicza

|

2006

|

tom R. 10, nr 2 (77)

255-261

PL

Celem pracy było zbadanie wpływu parametrów aglomeracji nawilżeniowej poprzez mieszanie (laboratoryjny mieszalnik lemieszowo-płużący Lödige typ L5) na gęstość i porowatość otrzymywanych granulatów. Badano wpływ takich parametrów procesu jak: prędkość mieszadła impelerowego, czas mieszania, ilość i rodzaj cieczy nawilżającej. Zmiana poziomu zmiennych procesu miała bardziej znaczący wpływ na wymiar cząstek niż na gęstość nasypową, porowatość złoża czy gęstość rzeczywistą otrzymywanych aglomeratów.

EN

The laboratory high-shear granulator (the Lödige Plughshare Mixer L5) was tested in a study investigating the influence of various granulation parameters (granulation time, the impeller speed and the amount of binder / water) on granules size, loose and tapped bulk densities, apparent particle density and porosity. Particles size was as a sensitive indicator of changes during granulation.