Wyniki wyszukiwania - Biblioteka Nauki

1

Diagnostic and Therapeutic Thoracoscopy (Videothoracoscopy) in Malignant Pleural Effusion - Our Experience

100%

Kacprzak G. , Kołodziej J. , Pawełczyk K. , Marciniak M. , Rzechonek A.

Polish Journal of Surgery

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2008

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tom 80

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nr 1

35-41

EN

Diagnosis and treatment of patients with malignant pleural effusion (MPE) is a serious problem for clinicians.The aim of the study were: to evaluate the diagnostic and therapeutic value of thoracoscopy and videothoracoscopy (VTS) and to determine the efficiency of using talc for the management of MPE.Material and methods. Between January 1996 and December 2006, thoracoscopy (VTS) was performed in 95 patients. A 4 g dose of talc was used for pleurodesis. Out of the 95 diagnostic procedures, malignancy was diagnosed in 94 (98.9%) patients. Patients were divided into two subgroups: subgroup A, patients (n=4) who died within first month, and subgroup B, patients (n=91) who lived more than one month. In subgroup A, complete remission (CR) was achieved in four (100%) patients until they died. In subgroup B, CR was achieved in 90 (98.9%) patients after one month, with relapse (R) occurring in 1 (1.1%) patient. After three months, CR was achieved in 86 (94.5%), partial remission (PR) in three (3.3%), and R in two (2.2%) patients. After six and nine months, CR was achieved in 85 (93.4%), PR in three (3.3%), and R in three (3.3%) patients. Postoperative complications, side effects after applying talc, and general performance were assessed. Difficulties in lung expansion requiring redrainage occurred in four (4.2%) patients. Fever appeared in 79 (83.2%) patients, while pain appeared in 90 (94.7%) patients. After treatment, the number of patients classified as I on the WHO scale increased from 36.8% to 74.7%, while the number of patients classified as III on the WHO scale decreased from 10.5% to 2.1%.Conclusions. Thoracoscopy (VTS) significantly improves diagnostic effectiveness in cases without cytological and histological diagnosis and is a method of treatment for MPE. Very good results were achieved after intrapleural administration of talc (CR occurred in 93.4% patients). The most common side effect of administering talc was pain.

2

Utilization of N-carboxymethyl chitosan as a selective depressant for talc in flotation of chalcopyrite

100%

Liu C. , Feng Q. , Shi Q. , Zhang W. , Song S.

Physicochemical Problems of Mineral Processing

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2019

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tom Vol. 55, iss. 1

108--115

EN

Flotation separation of chalcopyrite from talc is difficult because of the natural hydrophobicity of two minerals. In this work, the flotation separation of chalcopyrite from talc using N-carboxymethyl chitosan as a depressant for talc was studied. The micro-flotation results indicated that the flotation separation of chalcopyrite from talc cannot be realized effectively at pH 9 with low concentration of N-carboxymethyl chitosan, in the presence of calcium ions, talc was more efficiently depressed by N-carboxymethyl chitosan, while the chalcopyrite recovery was not influenced. Contact angle, zeta potential and adsorption results showed that Ca2+ and CaOH+ absorbed on the talc surface and increased the absorption amount of N-carboxymethyl chitosan on the mineral surface, and increased hydrophilicity of talc surface, resulting the selective depression for talc in chalcopyrite flotation.

3

Comparison of Jameson cell and jet diffuser flotation column

100%

Bilir K. , Ucar A. , Sahbaz O. , Gursoy H. , Oteyaka B.

Physicochemical Problems of Mineral Processing

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2018

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tom Vol. 54, iss. 1

174--181

EN

A Jet Diffuser Flotation Column (JDFC) is a newly designed flotation device which resembles the Jameson cell (JFC) in terms of operational principles, but it has an important difference regarding to the structural characteristics in the downcomer. The main difference of JDFC is the diffuser type of downcomer which has been designed using the hydrodynamic consideration and fluid mechanics principles. The aim of the design was to increase the device efficiency for coarse particle flotation. Therefore, the turbulence occurring at the end of the downcomer was reduced, and the detachment probability of the coarse particle decreased. In addition, a homogenous and stable foam zone in the cell was obtained. According to the experimental results carried out in a pilot scale showed that not only higher flotation performance in comparison to the Jameson cell was obtained specifically for the coarse particles but also the quiescent froth layer was acquired under the given conditions. In these experiments, a vertical pipe of JDFC having an inlet diameter of 60 mm and outlet diameters of 115, 125 and 135 mm was used with the separation tank with the diameter of 390 mm. By using the data, the pilot scale JDFC with the 4100 mm vertical pipe integrated with the separation tank was produced, and the flotation tests were carried out by using a talc ore. Finally, the talc recovery of 90% was obtained using the JDFC for the particle size of 350 μm.

4

The effect of a novel depressant on the separation of talc and copper –nickel sulfide ore

88%

Gu G. , Chen Z. , Zhao K. , Song S. , Li S. , Wang C.

Physicochemical Problems of Mineral Processing

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2019

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tom Vol. 55, iss. 1

116--127

EN

This paper researched the influence of the polysaccharide polymer sodium alginate (SAG) on the depression of talc at a fixed room temperature about 25 °C through micro flotation and batch flotation experiments, zeta potential and contact angle measurements as well as infrared spectroscopy analysis. The flotation results displayed that the SAG had a significant influence on the flotation of talc but less influence on sulphide flotation. Compared with the depressant carboxymethyl cellulose (CMC) and guar gum, using of the SAG gave the highest copper recovery. It could not only eliminate a talc removal step, but also significantly decrease in the depressant consumption by half at least. Sodium alginate apparently adsorbs on the talc surface and promotes hydrophilization, as revealed by contact angle tests (contact angle decreased from 75 to 33° after treating with SAG). It is demonstrated that the SAG obviously absorbed at the surface of talc but rarely for chalcopyrite through the results of zeta potential measurements and infrared spectroscopy analysis.

5

The effect of lizardite on talc flotation using carboxymethyl cellulose as a depressant

88%

Deng J. , Yang S. , Zhang W. , Liu C. , Li H.

Physicochemical Problems of Mineral Processing

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2020

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tom Vol. 56, iss. 4

702--709

EN

The effect of lizardite on talc flotation when using carboxymethyl cellulose (CMC) as a depressant was studied by micro-flotation experiments and adsorption measurements, zeta-potential measurements, magnesium ion dissolution analysis, and solution chemistry calculation. The results for the micro-flotation experiments showed that the addition of lizardite further decreased the floatability of talc at pH 8.5 when using CMC as the depressant. The mechanism was that magnesium ions dissolved from lizardite lattice, then formed hydrolyzed species of magnesium cations and interacted with talc surfaces, which promoted CMC adsorption, and thus decreasing talc floatability.

6

Flotation separation of chalcopyrite from talc using carboxymethyl chitosan as depressant

88%

Qian G. , Bo F. , Danping Z. , Jujie G.

Physicochemical Problems of Mineral Processing

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2017

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tom Vol. 53, iss. 2

1255--1263

EN

Flotation separation of chalcopyrite from talc using carboxymethyl chitosan as a depressant was studied. Flotation tests indicated that carboxymethyl chitosan had a selective depression effect on talc and the use of carboxymethyl chitosan as the depressant could achieve flotation separation of chalcopyrite from talc at pH 7. Adsorption studies showed that carboxymethyl chitosan only adsorbed on the surface of talc. This was the reason why carboxymethyl chitosan had high depression selectivity for talc. The zeta potential measurements and XPS analysis indicated that carboxymethyl chitosan adsorbed on the talc surface mainly through physical interaction and hydrophobic interaction may be the main driving force.

7

Central composite design application in oil agglomeration of talc

88%

Polowczyk I. , Kozlecki T.

Physicochemical Problems of Mineral Processing

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2017

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tom Vol. 53, iss. 2

1061--1078

EN

Talc has many applications in various branches of industry. This material is an inert one with a naturally hydrophobic surface. Talc agglomeration is within the wide interest of pharmaceutical industry. Oil agglomeration experiments of talc were carried out to find out and assess the significance of experimental factors. Central composite design (CCD) was used to estimate the importance and interrelation of the agglomeration process parameters. Four experimental factors have been evaluated, i.e. concentration of cationic surfactant and oil, agitation intensity as well as time of the process. The median size of agglomerates (D50) and the polydispersity span (PDI) were used as the process responses. Logarithmic transformations of the responses provide better description of the model, than untransformed responses, with the reduced cubic model for D50 and quadratic model for PDI. This was supported by the Box-Cox plots. It was shown that there were many statistically important factors, including the concentration of cationic surfactant and stirring rate for D50, concentration of oil and stirring rate for PDI, as well as various interactions, up to third order for D50. Optimal conditions for minimum values of reagent amounts as well as mixing time and intensity for the maximum size of agglomerates but of rather narrow size distribution were found.

8

Influence of fenugreek-gum and particle size on performance of talc flotation

88%

Gu G. , Mo C. , Zhao K. , Chen Z. , Wang X.

Physicochemical Problems of Mineral Processing

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2018

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tom Vol. 54, iss. 3

1026--1033

EN

Talc usually exists as a gangue mineral in copper-nickel sulfide, molybdenite etc. In order to separate precious metals, naturally hydrophobic talc should be depressed effectively in flotation process. The effect of fenugreek-gum (FG) on the flotation performance of talc with different particle sizes was studied. The depression mechanism was investigated extensively through tests of flotation, adsorption and zeta potential, as well as infrared spectroscopy and laser particle size analysis. Flotation results indicated that the FG had a strong depression ability for talc with the particle size of -0.074 + 0.037 mm, -0.037 mm and -0.010 mm when proper dosage of FG was added. The coarse talc was completely depressed by 2.5 mg/ dm3 FG. When the particle size decreased, more FG was required to obtain the maximum depressing effect, which was verified by adsorption tests. FG reduced the electronegativity on the talc surface by chemical adsorption, and flocculation of talc powders caused a high efficient depressing effect.

9

Comparative analysis of process parameters of talc mechanical activation in centrifugal and attrition mill

88%

Andric L. , Terzic A. , Acimovic-Pavlovic Z. , Pavlovic L. , Petrov M.

Physicochemical Problems of Mineral Processing

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2014

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tom Vol. 50, iss. 2

433--452

EN

The efficiency of talc mechanical activation by means of two different mechano-activators - centrifugal and attrition mill is investigated in this study and the comparative analysis of the characteristics of obtained talc powders is presented. A new approach for obtaining high-grade talc concentrate with low Fe2O3 content is achieved through effect of mechanical activation of talc accompanied by hydrometallurgical process. The applied mechanical activation process conditions of ultra-centrifugal mill were defined by number of rotor revolutions, sieve mesh size, and current intensity. These operating parameters of the ultra-centrifugal mill were variable. Ultra fine grinding of talc in attrition mill (attritor) was carried out in various time intervals - from 5 to 15 min. The following technological parameters of the mechanical activation were monitored: time of mechanical activation, circumferential rotor speed, capacity of ultra-centrifugal mill, and specific energy consumption. The investigation was based on a kinetic model. The structure and behavior of activated samples were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) analysis, and differential thermal analysis (DTA).

10

Influence of dry grinding on physicochemical and surface properties of talc

75%

Arsoy Z. , Ersoy B. , Evcin A. , Icduygu M. G.

Physicochemical Problems of Mineral Processing

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2017

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tom Vol. 53, iss. 1

288--306

EN

In this study the effect of dry grinding on hydrophobicity, surface free energy (SFE), particle size distribution, surface area, porosity, oil absorption, and whiteness of talc was investigated. The dry grinding was performed in a vibrating ball mill at various grinding times (5-150 min) by keeping the grinding parameters constant such as the number of ball, ball size, the amount of talc, vibration frequency and amplitude. Then, the contact angle measurements were performed on disc-shaped samples produced under a hydraulic press by using a sessile drop method with different liquids (water, formamide, diiodomethane, and ethylene glycol), and surface free energies (mJ/m2) were calculated according to OCG-AB (van Oss-Chaudhury-Good Acid-Base) method by using the obtained contact angle values. In addition, the physicochemical analyses given above were carried out for each ground sample. According to the obtained results, the water contact angle and SFE of the original sample were 63.800 and 48.70 mJ/m2, respectively. The lowest and highest contact angle values for the samples were obtained as 59.300 and 70.770 at grinding times for 5 and 15 min, respectively. It was also determined that the grinding time over 30 min showed no significant effect on the contact angle and SFE values of the samples. Similarly, the grinding time vs. SFE, and the grinding time vs. contact angle curves showed a similar trend. Parallel to the increase in the surface area upon the grinding, a small increase in the oil absorption and whiteness of talc was also determined.

11

Porównanie fizykochemicznych i użytkowych właściwości talku oraz syntetycznych kompozytów tlenkowych MgO·SiO2

75%

Ciesielczyk F. , Krysztafkiewicz A. , Jesionowski T. , Modrzejewska-Sikorska A.

Przemysł Chemiczny

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2009

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tom T. 88, nr 8

924-928

12

Beneficiation of Talc-Magnesite Ore with Cu-Co Mineralization

63%

Brezani I. , Sisol M. , Marcin M. , Sykora M. , Matasovsky M. , Varga P.

Inżynieria Mineralna

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2019

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tom R. 21, nr 1

141--144

EN

Magnesite ore with a low chalcopyrite – cobaltite mineralization was subjected to a series of separations designed to evaluate the possible concentration of the two accessory minerals. Although the Cu-Co grade in the ore (> 0.01% Co, > 0.1% Cu) is significantly lower than the typical economic grades, content of the main valuable mineral for which the ore is mined and processed in combination with a listing of cobalt as a critical raw material, coupled with their higher price might compensate for the additional beneficiation stages. The ore was first crushed and subsequently classified to -100 μm and +100 -400 μm size fractions. The fine fraction was upgraded by froth flotation processing in laboratory froth flotation cell. The coarser fraction was processed in several separation stages including gravity separation on shaking table, magnetic separation and corona electrostatic separation. The same procedure was also repeated with a higher-grade sample as a verification of the procedures. Preliminary results suggest that the accessory minerals can be separated from the talc-magnesite ore and individual mineral concentrates with about 19% Co and 28% Cu were prepared. However, further work must be done to achieve desirable recoveries for the processing to be economically viable.

PL

Ruda magnezu o niskiej mineralizacji chalkopirytu – kobaltytu została poddana serii separacji mających na celu ocenę możliwego uzysku dwóch minerałów towarzyszących. Chociaż zawartość Cu-Co w rudzie (> 0,01% Co,> 0,1% Cu) jest znacznie niższy niż wartości opłacalne ekonomicznie, zawartość głównego cennego minerału (magnezytu) , dla którego ruda jest wydobywana i przetwarzana w połączeniu z zawartością kobaltu jako surowca krytycznego może zrekompensować koszt dodatkowych etapów wzbogacania. W pierwszym etapie rudę kruszono, a następnie klasyfikowano do frakcji o wielkości -100 μm i +100 -400 μm. Drobną frakcję poddawano flotacji pianowej w laboratoryjnej maszynce flotacyjnej. Grubsza frakcja była przetwarzana w kilku etapach, w tym separacja grawitacyjna na stole wstrząsanym, separacja magnetyczna i separacja elektrostatyczna. Ta sama procedura została powtórzona z próbką o wyższych zawartościach. Wstępne wyniki sugerują, że minerały towarzyszące można oddzielić od rudy talku i magnezytu i zyskano koncentraty mineralne z zawartością około 19% Co i 28% Cu. Jednakże konieczne są dalsze prace w celu osiągnięcia pożądanych uzysków, aby przetwarzanie było opłacalne ekonomicznie.

13

Synthesis and characterization of Poly(n-ethyl aniline) / Talc composite materials

63%

Anakli D. , Cetinkaya S. , Karakisla M. , Sacak M.

Inżynieria Mineralna

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2013

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tom R. 14, nr 2

115--118

EN

A new substituted polyaniline/layered talc conductive composite material were synthesized chemically using ammonium persulfate as oxidizing agent in aqueous HCl medium. The oxidant type, N-ethyl aniline to oxidant mole ratio and N-ethyl aniline concentration on the PNEAn content and conductivity of the composite were investigated as the effect of the polymerization conditions. Optimum reaction conditions were outlined as NEAn/oxidant ratio 1 and 0.2 M NEAn monomer concentration with (NH4)2S2O8 on the poly(N-ethyl aniline) yield and conductivity. The conductive composites were characterized by two probe technique for surface resistance and thermo gravimetric analysis (TGA) techniques. The increased thermal stability of the composite compared to that of pure polymer was obtained by the thermogravimetric analysis method.

PL

Nowy przewodzący materiał kompozytowy podstawiony polianiliną/warstwowany talkiem zsyntetyzowano chemicznie przy użyciu nadtlenodisiarczanu amonu jako czynnika utleniającego w wodnym kwasie chlorowodorowym. Badano rodzaj utleniacza, anilinę N-etylową do stosunku molowego utleniacza oraz stężenie aniliny N-etylowej w PNEAn [Poly( N-ethyl aniline)] oraz przewodność kompozytu co jednocześnie było skutkiem warunków polimeryzacji. Optymalnymi warunkami jakie określono dla reakcji to NEAn/utleniacz w stosunku 1 oraz 0,2M stężenie monomeru NEAn wraz z (NH4)2S2O8 na polianilinie N-etylowej. Kompozyty przewodzące zostały scharakteryzowane przez badanie oporu powierzchni oraz analizę termograwimetryczną (TGA). Zwiększona stabilność termiczna kompozytu została porównana do tej z czystego polimeru została określona przez metodę termograwimetryczną.

14

Glikoza odpadów sztywnych pianek modyfikowanych kredą, talkiem i boraksem

63%

Czupryński B. , Paciorek-Sadowska J. , Liszkowska J. , Lewandowski R.

Czasopismo Techniczne. Mechanika

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2009

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tom R. 106, z. 1-M

77-80

PL

Glikolizie poddano odpady sztywnych pianek poliuretanowo-poliizocyjanurowych napełnianych 15% masowych kredy, 15% masowych talku i 5% masowych boraksu. Glikolizę prowadzono w glikolu dietylenowym i etanoloaminie. W wyniku glikolizy otrzymano produkty barwy brązowej. Produkty glikolizy pianek z talkiem i kredą zawierają biały osad. Glikolizaty charakteryzują się liczbą hydroksylową w granicach 250,3-800 mgKOH/g oraz lepkością od 152 mPa[.]s do 844,4 mPa[.]s. Glikolizaty wykazują przydatność do syntezy "nowych" pianek poliuretanowo-poliizocyjanurowych.

EN

The waste rigid polyurethane-polyisocyanurate foams containing as filler 15% w/w of chalk, 15% w/w of talc and 5% w/w of borax were subjected to glycolysis. Glycolysis run in diethylene glycol and ethanolamine. As a result of glycolysis, the brown products were obtained. The white sediment was observed in glycolysis products of foams with talc and chalk. Glycolysates are characterized by hydroxyl number within the range from 250,3 to 800 mgKOH/g and viscosity from 152 mPa[.]s to 844,4 mPa[.]s. Properties of glycolysates are suitable for synthesis of the "new" polyurethane-polyisocyanurate foams.

15

Flotation method in talc raw material processing from the Gemerská Poloma deposit in Slovakia

63%

Sidorová M. , Čorej P.

Gospodarka Surowcami Mineralnymi

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2013

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tom T. 29, z. 3

37--46

PL

Artykuł przedstawia przydatność metody flotacyjnej w przeróbce kopaliny talkowej pochodzącej ze złoża Gemerská Poloma. Wnioski oparte są na analizie wyników badań kontrolowanych próbek materiału z prób produkcyjnych, które zostały przeprowadzone w dwóch instalacjach flotacyjnych. Ocena wyników tych prób przemysłowych, w tym analizy chemicznej i innych analiz jakościowych przeprowadzonych na próbkach kontrolnych, potwierdzają stosunkowo wysoki poziom białości – w zakresie od 83,9–88,0% – w otrzymanych koncentratach talku. Wiadomo jednak, że surowiec talkowy osiągnie swój ostateczny poziom białości po jego zmieleniu do docelowej granulacji. Badania potwierdzają również wysoką skuteczność separacji pirytu i innych minerałów towarzyszących w trakcie flotacji. Na podstawie wyników analizy chemicznej koncentratów talku, uzasadnione jest stwierdzenie, że metoda flotacji może być uznana za odpowiednią metodę wzbogacania kopaliny talkowej pochodzącej ze złoża Gemerská Poloma. Złoże talku Gemerská Poloma zostało udokumentowane pod koniec lat dziewięćdziesiątych XX wieku. W 1988 roku podczas badań geologicznych w rejonie Gemerská Poloma na końcu doliny Dlhá, w wyniku przeprowadzonych prac wiertniczych (3 otwory) stwierdzono mineralizację talkowo-magnezytową. Unikalne złoże talku może mieć duże znaczenie na rynku europejskim, będąc porównywalnym do największych światowych złóż tej kopaliny. Eksperci uważają złoże talku Gemerská Poloma pod względem wymiarów, jakości kopaliny i ilości zasobów, jako jedno z największych na świecie. Jego kluczową zaletą jest dobre strategiczne położenie w centrum Europy. Oceny ekonomiczne tego złoża dają perspektywę długoletniej zyskownej działalności produkcyjnej, a działalność ta może także częściowo ożywić górniczo-geologiczny rynek pracy w tym regionie. Popyt na ten surowiec w Europie ma stałą tendencję wzrostową.

EN

This article describes the suitability of the flotation method in the processing of talc raw material from the Gemerská Poloma deposit. The conclusions are based on the analysis of test results of controlled material samples from plant trials that were conducted in two flotation facilities. The evaluation of the results of the trial runs, chemical analysis, and other analyses conducted on the control mineral samples confirmed relatively high levels in the range between 83.9–88% of whiteness in the sample mineral concentrate. However, it is known that the talc will reach its final level of whiteness after it is ground into more refined particles. The trials also confirmed high effectiveness of separation of pyrite and other accompanying minerals. Based on the results of the chemical analysis of the concentrates, it is safe to conclude that the flotation method can be deemed suitable for the enriching of talc extracted from the Gemerská Poloma deposit. The talc deposit at Gemerská Poloma was already identified in the late 90s. In 1988 during geological surveys in Gemerská Poloma at the end of Dlhá Valley, talc magnesite mineralization was found by three drillings. A unique talc deposit was verified of European significance comparable to the largest global deposits by its. Experts regard the Gemerské talc deposit in terms of its dimensions, quality, and quantity as one of the most important in the world. Its key advantage is a good strategic location in the centre of Europe. The economic prospects of this deposit are estimated to offer many years of potential benefits which will partly revive the labour market for the mining-geological specialisation. Demand for this industrial mineral in Europe has an increasing tendency.

16

Badania wytrzymałości zmęczeniowej i pełzania kompozytów polimerowych z napełniaczem proszkowym i włóknistym

63%

Gnatowski A. , Kwiatkowski D. , Baranowski W.

Kompozyty

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2009

|

tom R. 9, nr 1

94-98

PL

Przedstawiono wyniki badań wytrzymałości zmęczeniowej na zginanie, zależności wytrzymałości zmęczeniowej od twardości oraz procesu pełzania kompozytu polipropylenu z włóknem szklanym, polipropylenu z talkiem oraz polistyrenu i polietylenu o małej i dużej gęstości. Badania wytrzymałości zmęczeniowej na zginanie przeprowadzono za pomocą urządzenia umożliwiającego obciążenie działające obukierunkowo na próbki z badanych materiałów polimerowych wytworzonych metodą wtryskiwania. Badanie pełzania przeprowadzono przy naprężeniu wywołanym w próbce, równym 5, 10, 20, 30 i 50 MPa. Badania wykonano dla próbek z polimerów i kompozytów wytworzonych metodą wtryskiwania przy optymalnych parametrach przetwórczych. Określono wytrzymałość zmęczeniową dla różnego typu badanych materiałów polimerowych. Ustalono wykres Wöhlera dla cykli symetrycznych przy zginaniu wahadłowym dla badanych materiałów. Również wyznaczono wpływ twardości, pełzania materiału i rodzaju napełniacza na wytrzymałość zmęczeniową podczas zginania. W przeprowadzonych badaniach w przypadku wytrzymałości zmęczeniowej odnotowano najwyższe wartości dla polipropylenu, a niższe dla jego kompozytów z napełniaczem, szczególnie typu włóknistego. Niższe wartości wytrzymałości zmęczeniowej uzyskano również dla polistyrenu i polietylenu. Charakter zmian tych wartości wskazuje na zależność wytrzymałości zmęczeniowej od zmęczenia statycznego i twardości badanych materiałów polimerowych.

EN

Polymer mixing with filler is presently one of the most effective and the most intensely developing methods of physical properties modification for polymers. Polymeric composites play crucial role in development of application of technological polymers. During last twenty years composites of polymers have gained on interest, as they have appeared as new group of polymeric materials with interesting and sometimes very specific properties. In this work the results of investigations of mechanical properties polystyrene, polyethylene, polypropylene and polypropylene with addition of glass fibre and talc were presented. The properties of the polymer composites depend significantly on the type of the components. That kind of influence manifests especially in the change of the mechanical properties. The investigations for the influence of filler and kind of polymer on the fatigue strength and creep during bending have been conducted. Research of fatigue strength was passed by means of the device making possible impromptu cyclical to bend samples from investigated polymer materials produced with the injection method. The process of the creep was passed at the tension called out in the sample equal 5, 10, 20, 30 and 50 MPa. Research were executed for samples from polymers and composites produced with the method of the injection at optimum-manufacturing parameters. The changes of the value of fatigue strength for the different type of investigated polymer materials was obtained. The graph of Wöhler for symmetrical cycles at the pendulum-inflexion for investigated materials was fixed. Also the essential influence on fatigue strength a note during the fall of the creep and the hardness of the polypropylene composite of the both with the powder filler as and to glass fibre filler, the polystyrene and the polypropylene was made. The influence of these properties on fatigue strength on the inflexion was qualified. In passings research in the chance of fatigue strength a note highest values of the polypropylene, and lower for his composites with the filler, especially the fibrous type was made. Lower values of fatigue strength also for the polystyrene and the polythene was obtained. The character of changes of these values evidences the dependence of fatigue strength from the susceptibility on the statical fatigue and hardnesses of investigated polymer materials.

17

Wykorzystanie talku w procesie mineralnej karbonatyzacji - badania doświadczalne rozpuszczalności

63%

Jaschik J. , Warmuziński K. , Jaschik M.

Inżynieria i Aparatura Chemiczna

|

2010

|

tom Nr 4

28-29

PL

Przedstawiono wyniki badań rozpuszczalności talku w roztworach kwasu octowego, siarkowego i chlorku amonu. Badania wykonano dla zmiennych wartości temperatury, prędkości obrotowej mieszadła i stężenia rozpuszczalnika. Stopień ekstrakcji magnezu z minerału do roztworu po ok. 4 godzinach prowadzenia procesu wynosił od 0,4% (woda) do 5-6% (kwas siarkowy). Otrzymane w badaniach wartości stopnia ekstrakcji jonów magnezu są niewystarczające z punktu widzenia możliwości wykorzystania talku w procesie mineralnej karbonatyzacji.

EN

The results of experimental study on natural talc dissolution are presented in the paper. The investigations were made for acetic acid, sulfuric acid and ammonium chloride solutions at different values of temperature, mixing velocity and solvent concentration. After 4 hours of mixing the fraction of extraction of magnesium ions was equal to 0.4% in water and 5-6% in sulfuric acid. The values of extraction obtained are insufficient for mineral carbonation process.

18

Badania wpływu konstrukcji segmentów ślimaków wytłaczarek dwuślimakowych współbieżnych oraz parametrów technologicznych na proces wytłaczania polipropylenu modyfikowanego talkiem

63%

Stasiek A. , Łubkowski D.

Przetwórstwo Tworzyw

|

2010

|

tom [R.] 16, nr 1

8-15

PL

Napełniacze służą do modyfikowania niektórych właściwości polimeru i dodawane są do tworzywa najczęściej podczas procesów przetwórstwa. Do najczęściej napełnianych polimerów należą: polichlorek winylu, poliamidy, poliolefiny. Do wytwarzania tworzyw o wysokim stopniu napełnienia stosuje się przede wszystkim wytłaczarki dwuślimakowe współbieżne o segmentowej budowie ślimaków, która umożliwia konfigurowanie zespołu wytłaczającego w zależności od wymagań technologicznych. W tym celu stosuje się segmenty ślimaków transportujące, ugniatające oraz mieszające.

EN

Fillers used for modification of some properties of polymer are usually added to plastic material during processing. The most often fillers are used for polyvinyl chloride, polyamides and polyolefines. The co-rotating twin-screw extruders having screws of segment structure are mainly used for manufacturing of high-filled plastics. This structure of screws enables the configuration of extrusion set depending on technological requirements. The transporting, kneading and mixing segments of screws are used for this purpose.

19

Crystallization kinetics of polycaprolactone in nanocomposites

63%

Mucha M. , Tylman M. , Mucha J.

Polimery

|

2015

|

tom T. 60, nr 11-12

686--692

EN

The paper presents research results on the crystallization kinetics of polycaprolactone (PCL) with micro- and nano-additives such as talc (nucleation agent) and nanosilver (antibacterial agent). The process of isothermal crystallization was studied in a narrow temperature range 38.5—41.5 °C using Differential Scanning Calorimetry (DSC) and Thermooptical Analysis (TOA) methods. The kinetics of the process are described using the Avrami model. The parameters n and log K of the equation were calculated. Changes in the half time of crystallization, degree of crystallinity and melting temperature of the polymer under the influence of the fillers and the conditions of crystallization were analyzed.

PL

Przedstawiono wyniki badań kinetyki krystalizacji polikaprolaktonu z mikro- oraz nanododatkami, takimi jak talk (czynnik nukleacji) i nanosrebro (dodatek antybakteryjny). Metodami różnicowej kalorymetrii skaningowej (DSC) oraz analizy termooptycznej (TOA) badano proces krystalizacji w zakresie temperatury 38,5—41,5 °C. Kinetykę procesu opisano za pomocą modelu Avramiego. Wyznaczono parametry n oraz log K. Przeanalizowano wpływ dodatku napełniaczy i warunków prowadzenia procesu krystalizacji na zmiany połówkowego czasu krystalizacji, temperatury topnienia oraz stopnia krystaliczności polimeru.

20

Distribution of microhardness in polypropylene/talc microcomposite

63%

Bechikhi Y. , Bouiadjra B. B. , Bouziane M. M. , Bouiadjra B. A. B. , Benbarek S.

Composites Theory and Practice

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2021

|

tom R. 21, nr 4

141--148

EN

In this study the distribution of microhardness in a polypropylene microcomposite reinforced with talc microparticles was measured experimentally. The microhardness was measured at different points of the composite material to try to observe the effects of the talc particles and their proportion in the composite on the hardness of the reinforced polymer. Four proportions of talc were used: 5,40 and 50 wt.%, in addition to virgin polypropylene, which was taken as the reference. Statistical analysis was performed on the distribution of the microhardness in the PP+talc composites to determine the average microhardness and the standard deviation. The obtained results reveal a random distribution of the microhardness of the composite, but in general the presence of talc particles increases the microhardness of the polypropylene.