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1

Innovative correlation relating the destruction of graphite flakes to the morphology characteristics of minerals

Wang Nailing, Xu Xinyang, Jiang Yanxin, Yuan Zhitao, Lu Jiwei, Li Lixia, Meng Qingyou

Physicochemical Problems of Mineral Processing

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2024

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Vol. 60, iss. 1

art. no. 183655

EN

The morphology characteristics (sphericity, roundness, and surface roughness) affecting the destruction of gangue minerals on graphite flakes during the grinding process were systematically analyzed. Coupled with MS and SEM, sphericity analysis showed that graphite was flaky, which was similar to muscovite but different from granulous quartz and albite, and the roundness of the four minerals from high to low was graphite, quartz, albite, and muscovite. AFM analysis showed that the surface roughness of graphite and muscovite was very low compared to that of quartz and albite (higher than quartz). The size and crystal integrity of graphite flakes were both destroyed by gangues during the grinding process, and the destruction of quartz and albite was serious compared to that of muscovite. Sphericity dominantly affected the destruction: the larger the sphericity, the more serious the destruction, which was also negatively related to roundness but positively related to surface roughness.

2

Glass microspheres thermo-deformation sintering processes in the technologies of obtaining materials for underwater technical equipment

Kazymyrenko Yuliia, Solomoniuk Natalya, Drozd Oxana

Polish Maritime Research

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2023

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nr 3

174--180

EN

In this work, the important scientific and technical problem of creating multifunctional composite materials for shipbuilding and ocean engineering was solved. The work aimed to study the thermal deformation processes of sintering glass microspheres to obtain lightweight glass composites with a cellular structure that provides positive buoyancy and sound insulation properties. For this purpose, glass microspheres of Na2O‒SiO2 and Na2O‒B2O3‒SiO2 composition with a dispersion of 10 to 60 μm were used as raw materials. They were sintered to form a closed, porous structure. The theoretical substantiation of technological parameters is based on the concepts of solid state and glassy state chemistry and physicochemical concepts of glass softening processes. The process of hot-pressing glass microspheres without plasticisers and additives was investigated. The author’s own laboratory equipment was used for the experiments. The sintering intensity was determined from the results of shrinkage processes; the kinetic shrinkage curves were constructed in semilogarithmic coordinates. The glass composite samples were examined by optical and electron microscopy. As a criterion, the storage of spherical microspheres under the influence of simultaneous heating to 700 °C with the application of pressure in the range of 0,5 to 1,5 MPa was chosen. It was established that the formation of a predominantly closed-porous structure of glass composites with a density of 350...600 kg/m3 occurs by the mechanisms of viscous glass phase flow through liquefaction processes in the walls of microspheres. At the same time, shrinkage processes in the linear direction reach up to 50%. The acoustic properties were investigated by measuring the differences in sound pressure levels in octave frequency bands using a Kundt pipe. The water absorption of the glass composite samples was determined at hydrostatic pressures up to 20 MPa. The research results were compared with the characteristics of analogue composites, such as syntactic foams and foam glass. The developed materials can be used in the design and manufacture of technical equipment for research and maintenance of underwater infrastructure. The prospects for further research are related to the feasibility study and marketing research on implementing the developed glass composites.

3

Moisture dependent: physical properties of baobab seeds (Adansonia digitata L.)

Lamidi Wasiu Agunbiade, Ogunlade Clement Adesoji, Olaniyan Adetutu Rianat, Shittu Kabiru Alani, Murtadha Mosobalaje Abdulsalam, Ajibade Adenike Favour, Fadeyibi Adesina

Agricultural Engineering

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2023

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Vol. 27, No. 1

33--46

EN

The research investigated physical properties of baobab seeds to determine suitable equipment for the processing of its seeds. Pods of baobab used in the study were collected at a local farm in Ilorin, North Central Nigeria. Physical properties of the samples, such as moisture contents, mass, axial dimensions, shape indices, true and bulk densities, porosity, angle of repose and surface area were determined. The results showed that physical properties of baobab seeds were stable for moisture content, ranging between 12 to 18% dry mass (dm). The 100 seed mass (g) and geometric mean diameter increased from 0.60 g to 0.62 g and 10.12 to 10.27 mm respectively, in the moisture range of 12 to 18% dm. Other studied ranges of physical properties ranges included: average length (12.22 to 12.63 mm), width (10.10 to 10.28 mm), thickness (8.23 to 8.42 mm,), sphericity, (81.23 to 82.56 mm), surface area (319.42 to 332.53 mm2 ), 50 seed mass (0.60 and 0.62 g), and 1000 seed mass (12 and 12.4 g) within the moisture content range of 12 to 18% dm. The angle of repose of baobab seeds decreased with an increase in moisture content. The maximum value of 29.18o was obtained at 14% moisture content while a minimum value of 24.42o was obtained at 18% moisture. Moisture content had a significant effect on coefficient of friction of baobab seeds on glass, stainless steel, plywood and rubber. In the same moisture range (12-18%), the static coefficient of friction for baobab seeds ranged from 0-739 to 0-905 on stainless steel, 0-960 to 1-190 on galvanized steel, 0-812 to 1-055 on plywood and 0- 496 to 0-950 on glass. The least coefficient of friction values were recorded on stainless steel and glass which implies that baobab seeds will move with lower resistance on these surfaces in post-harvest handling. On the other hand, the resistance will be higher on plywood and glass. The data obtained will serve as guide for agricultural and food engineers, food processors and technicians involved in design and construction of post-harvest equipment used for separating, cleaning, milling and other production processes, to which baobab seeds are subjected.

PL

W pracy zbadano właściwości fizyczne nasion baobabu w celu określenia parametrów urządzeń do ich przetwarzania. Strąki baobabu zostały zebrane w gospodarstwie w miejscowości Ilorin w północno-środkowej Nigerii. Właściwości fizyczne określone w pracy to zawartość wilgoci, masa, wymiary osiowe, wskaźniki kształtu, gęstość rzeczywistą i objętościową, porowatość, kąt usypu i powierzchnię. Wyniki wykazały, że właściwości fizyczne nasion baobabu są stabilne dla wilgotności pomiędzy 12 a 18% suchej masy (sm). W zakresie wilgotności od 12 do 18% sm stwierdzono wzrost masy 100 nasion (g) i średniej geometrycznej średnicy odpowiednio z 0,60 g do 0,62 g i 10,12 do 10,27 mm. Pozostałe zbadane zakresy właściwości fizycznych to: średnia długość (12,22 do 12,63 mm), szerokość (10,10 do 10,28 mm), grubość (8,23 do 8,42 mm), kulistość (81,23 do 82,56 mm), pole powierzchni (319,42 do 332,53 mm2 ), masa 50 nasion (0,60 i 0,62 g) oraz masa 1000 nasion (12 i 12,4 g) w zakresie wilgotności od 12 do 18% sm. Kąt usypu zmniejszał się wraz ze wzrostem wilgotności, maksymalną wartość 29,18o uzyskano przy wilgotności 14%, natomiast minimalną 24,42o przy 18% sm. Wilgotność miała istotny wpływ na współczynnik tarcia nasion baobabu na szkle, stali nierdzewnej, sklejce i gumie. W tym samym zakresie wilgotności 12-18% współczynnik tarcia statycznego dla nasion baobabu wynosił od 0-739 do 0-905 na stali nierdzewnej, 0-960 do 1-190 na stali ocynkowanej, 0-812 do 1-055 na sklejce i 0-496 do 0-950 na szkle. Najmniejsze wartości współczynnika tarcia odnotowano na stali nierdzewnej i szkle. Sugeruje to, że nasiona baobabu będą się przesuwać z mniejszym oporem na powierzchniach z tych materiałów, jeżeli wykorzysta się je do produkcji urządzeń przetwórczych, podczas większy opór wystąpi na sklejce i szkle. Uzyskane dane mogą posłużyć technologom rolnictwa i żywności, zakładom przetwórstwa żywności i konstruktorom maszyn do przetwórstwa baobabu, np. urządzeń do sortowania, czyszczenia, mielenia itp.

4

Ocena kulistości granul nawozów mineralnych metodą cyfrowej analizy obrazu

Leszczyński N., Węgrzyn A., Kocira S., Szparaga A., Zarajczyk J.

Przemysł Chemiczny

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2018

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T. 97, nr 4

639--643

PL

Poddano ocenie kulistość granul trzech różnych nawozów mineralnych: wieloskładnikowy nawóz Polifoska®6, mocznik Pulrea®N46 oraz granulowaną sól potasową. Pomiarów parametrów granul dokonano za pomocą mikroskopu cyfrowego z zastosowaniem dwuwymiarowej analizy obrazu. Granule oceniano w dwóch rzutach prostokątnych, a stopień kulistości określano dwiema metodami opartymi na definicjach Coxa oraz Coreya. Przebadano 6-7 frakcji każdego nawozu, a ich próby losowe składały się ze 100 granul. Wykazano, że współczynnik kulistości zależy nie tylko od rodzaju nawozu ale także od jego uziarnienia.

EN

Three com. fertilizers (granule size 1.00-6.30 mm) were studied for sphericity of granules by using a digital microscope with 3-dimensional image anal. Degree of sphericity depended not only on the fertilizer kind, but also on its granularity.

5

Analiza metod pomiaru i oceny odchyłek kulistości

Adamczak S., Stępień K.

Mechanik

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2018

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R. 91, nr 2

122--125

PL

Zagadnienia związane z pomiarami i oceną odchyłek kulistości nie są uregulowane w aktualnych dokumentach normalizacyjnych. Poza maszynami współrzędnościowymi nie ma również na rynku systemów do pomiaru odchyłek kształtu elementów kulistych. W artykule przedstawiono opisane w literaturze metody pomiaru i oceny odchyłek kulistości oraz perspektywy ich zastosowania w warunkach przemysłowych.

EN

Problems relating to measurements and evaluation of sphericity deviations are not described in contemporary standardization documents. Apart from coordinate measuring machines, in global market there are no commercially available systems allowing such measurements. The paper presents methods and systems for measurements of sphericity deviations that are described in the scientific literature as well as a prospective of their application under industrial conditions.

6

Analysis of results of circular tests for numerically controlled machine tools dependent on positions of tests in work spaces

Woźniak M., Majda P.

Advances in Manufacturing Science and Technology

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2016

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Vol. 40, nr 3

53--60

EN

This study presents analysis of circular test used according to ISO 230-4 for quick diagnostic Computerized Numerical Controls condition. We built virtual machine, which implements earlier calculations of Volumetric Error. Using this Virtual Machine we simulated testing of circularity of Computerized Numerical Control machine tools. Virtual test was taken in ten different places for three different machine tools. Those machines had different characteristics of kinematic errors and squarness and also different sizes of working spaces. We observed significant differences in those indicators in dependence of place where the test was taken.

PL

Zaprezentowano analizę wyników próby okrągłości wg ISO 230-4, stosowanej do szybkiej diagnostyki stanu obrabiarek sterowanych numerycznie. Zbudowano wirtualną maszynę, realizującą wyznaczoną doświadczalnie mapę błędów przestrzennego pozycjonowania. Przeprowadzono z jej użyciem symulację próby okrągłości obrabiarek sterowanych numerycznie. Symulację wykonano w dziesięciu różnych położeniach przestrzeni roboczej dla trzech różnych maszyn. Obrabiarki różniły się zarówno charakterystykami błędów kinematycznych i prostopadłości, jak i rozmiarami przestrzeni roboczej. Wykazano istotne różnice w wartości błędu okrągłości i sferyczności w zależności od położenia w polu roboczym maszyny.

7

Parametry kształtu ziaren gruntowych oraz analityczne sposoby ich wyznaczania

Szerakowska S.

Przegląd Geologiczny

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2014

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Vol. 62, nr 10/2

704--714

EN

Particle shape is a major factor conditioning behavior of soil, which in natural conditions is very diverse and complex. For the generally accepted characteristics describing the shape of granule was sphericity, angularity and surface microstructure. Due to the lack of specified by standards definition of shape and its properties and methods of their determination, over the years developed various definitions and methods of determination elaborated by many authors. The most popular parameters were sphericity and angularity, which results in a number of possible definitions of these parameters. Due to the complicated character of the microstructure of the granule surface, this parameter wasn't defined so many and is often overlooked when determining the shape of the aggregate. On the basis of literature data atempted to compilation definition and analythical methods of determining the characteristics of the shape of the granules. In further part of work drew attention to the subject of the shape of the granules and methods of its description in the standards EN ISO 14688-1:2006 force in mostcountries of the European Union and ASTM D 2488-00 used in the United States.

8

Aplikacja bezodniesieniowych metod oceny odchyłki kształtu w zastosowaniach medycznych

Ryniewicz A., Kowalski M.

Mechanik

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2014

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R. 87, nr 8-9CD1

337-348

PL

Ocena odchyłek kształtu powierzchni ślizgowych biołożysk ma szczególne znaczenie przy analizie tribologicznej stawów. W pracy przedstawiono pomiary odchyłek kształtu okrągłości i sferyczności głowy kości udowych drobiowych i wieprzowych z zastosowaniem bezodniesieniowych metod pomiarowych. Badania przeprowadzono z wykorzystaniem kształtografu Talycenta oraz ramienia pomiarowego wyposażonego w laserową głowicę pomiarową. Określono wartości odchyłek okrągłości w wybranych przekrojach oraz sferyczności w zależności od położenia osi funkcjonalnej stawu.

EN

Assessment of biobearings sliding surfaces shape deviations is of particular importance during the tribological joints analyzes. This paper presents measurements of roundness and sphericity deviations of poultry and pig femoral bone head using radial methods. The study was conducted using Talycenta machine and measuring arm equipped with a laser scanning head. Roundness values were specified in the selected sections and sphericity were evaluated depending on the position of the functional axis of the joint.

9

Problem of profile matching in sphericity measurements by the radial method

Janecki D., Adamczak S., Stępień K.

Metrology and Measurement Systems

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2012

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Vol. 19, nr 4

703-714

EN

At the Kielce University of Technology a new concept of accurate measurements of sphericity deviations of machine parts has been developed. The concept is based upon measurement of roundness profiles in many clearly defined cross-sections of the workpiece. Measurements are performed with the use of typical radial measuring instrument equipped with a unit allowing accurate positioning of the ball. The developed concept required finding a solution to numerous problems relating to the principle of the radial measurement. One of the problems to be solved was matching of measured roundness profiles. The paper presents an outline of the developed concept of sphericity measurement, a mathematical model of profile matching and results of the verification of the model.

10

Problemy pomiaru odchyłek kulistości

Adamczak S., Janecki D., Stępień K.

Archiwum Technologii Maszyn i Automatyzacji

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2010

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Vol. 30, nr 2

61-66

PL

W artykule przedstawiono analizę aktualnego stanu wiedzy o pomiarach odchyłek kulistości oraz założenia opracowanej koncepcji pomiaru kulistości metodą kombinowaną, umożliwiającą pomiar zarysów okrągłości przedmiotu w kilku przekrojach, tzw. południkowych, a następnie pomiar zarysu okrągłości tzw. równikowego. Do takich pomiarów mogą być wykorzystane promieniowe przyrządy pomiarowe wyposażone w odpowiednie zespoły mocujące przedmiot.

EN

In hitherto practice sphericity measurement methods have been based on measurement of roundness profiles in a few selected sections of the sphere and that is why they cannot give accurate quantitative and qualitative information on the investigated surface. Therefore producers of spherical machine parts (roll bearing or automotive industry) expect development of the concept that would allow full graphical presentation of the measured surface and its reliable evaluation by selected parameters. The method that could meet these expectations is so-called combined method. This method allows measurement of roundness profiles of the workpiece to be set on the measuring table in a few meridianal sections and then measurement of the roundness profile in one parallel section. Such measurement can be performed by radius change measuring devices equipped with appropriate fixing units. The paper presents the current state-of-the-art on the measurements of sphericity deviations and fundamentals of the developed concept.

11

Influence of developmental hip dislocation on femoral head sphericity: experimental study in dogs

Junk S., Topoliński T., Biliński P.J.

Acta of Bioengineering and Biomechanics

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2008

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Vol. 10, nr 4

33-37

EN

The aim of this study was to assess the growth and the changes in the shape of a femoral head in dog puppies with dislocated and unstable hip joints. Ten 5-week-old, mountain shepherd puppies were divided into two subgroups. In five animals, the femoral head was dislocated, and in the other five dogs, femoral head was reduced after the dislocation procedure, making the joint congruent but unstable. After 4 weeks the animals were euthanised. The optical method of contour measurement of the femoral head sphericity was used. The shape of the dislocated femoral head differed from the normal one. The medial part was extended into beard-like form. The overgrowth of the femoral heads was significant and from 38% to 61% larger compared with the normal contralateral head. The unstable head of the second group did not differ in the shape nor in its size from the contralateral normal one. The large adaptive and deforming changes of shape in the dislocated femoral heads in our study show the pronounced malformation of the joint. The shape of beard-like deformity may be explained by the enlargement of contact surface between the medial part of the head and illiac bone. The restricting modelling role of the acetabulum, the minor vascular impairment during the surgery and the short time of follow-up were possible factors contributing to the minimal changes of the affected femoral head in the unstable but congruent hip joint.

12

Pomiar współczynnika oporu i czynnika kształtu zrębków wierzby metodą aerodynamiczną

Pakowski Z., Krupińska B., Jankowiak T., Adamski R.

Inżynieria i Aparatura Chemiczna

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2007

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Nr 4-5

94-98

PL

W pracy przedstawiono pomiar czynnika kształtu i współczynnika oporu cząstek nieizometrycznych takich jak zrębki wierzby energetycznej. W celu wyznaczenia powyższych parametrów zaprojektowano i zbudowano aparat, w którym dane eksperymentalne otrzymano metodą aerodynamiczną. Uzyskano eksperymentalne zależności pomiędzy współczynnikiem oporu a liczbą Reynoldsa dla wszystkich badanych zrębków i uzyskano uśrednioną wartość sferyczności dla badanej mieszanki. Dla wszystkich badanych frakcji mieści się ona w zakresie 0.612-0.676.

EN

The paper presents the results of experimental determination of the shape factor and drag coefficient of non-isometric particles like wood chips. In order to determine these parameters a specially constructed set-up was built. The experimental relationship between the drag coefficient and the Reynolds number for wood chips investigated was obtained altogether with the mean value of sphericity equals to 0.612-0.676.

13

Light minerals of beach sediments from Southern Tamilnadu, south east coast of India

Cherian A., Chandrasekar N., Rajamanickam V.

Oceanologia

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2004

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No. 46 (2)

233-252

EN

A brief investigation of light minerals along the beaches between Valinokkam and Tuticorin has been carried out for the first time along the Southern Tamilnadu coast in order to discover the provenance of the sediments. The study spotlights a wide variation in light mineralogy along the three zones of the investigated area (Valinokkam, Vaippar and Tuticorin). A higher percentage of quartz is reported from the Valinokkam (48.34 to 68.63%) and Tuticorin zones (55.66 to 73.05%) than from the Vaippar zone (40.24 to 60.77%). The trend with regard to the maturity index is similar, with appreciably higher values in Valinokkam (1.15 to 1.89) and Tuticorin (1.61 to 1.94) than Vaippar (0.79 to 1.39). Morphological analysis of quartz grains shows a higher order of sphericity and roundness values in Valinokkam and Tuticorin as compared to Vaippar. Moreover, the surface texture of quartz grains observed with the aid of scanning electron microscope (SEM) photographs reveals the presence of different depositional environments and the multiple origin of beach sediments in the study area. From the present study of the light mineralogy of beach sediments, it is inferred that the source of the sediments is a mixed type: igneous and metamorphic crystalline rocks, together with palaeosediments.