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1

Preparation and Characterization of Porous Carbon/RDX Nanocomposite Energetic Materials

Jiang Ju, Su Jin-Xiao, Liu Zhi-Tao, Du Ping, Liao Xin, Li Xiao-An

Central European Journal of Energetic Materials

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2023

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Vol. 20, no. 3

284--301

EN

A novel energetic material was fabricated by filling porous carbon with 1,3,5-trinitro-1,3,5-triazinane (RDX) via the ultrasonic stirring method. Characterization (TEM, BET, XRD, FTIR, etc.) was performed to determine the micromorphology, crystal structure, and specific surface area. TEM images indicated that the RDX particles were homogeneously distributed in the channels of the porous carbon, FTIR spectra and the XRD curve of the C/RDX composite exhibited the combined characteristics of porous carbon and RDX. The BET test data also confirmed this situation. The thermal decomposition kinetics and thermodynamics of the C/RDX nanocomposite energetic material were investigated at various heating rates (5, 10, 15, and 20 K·min⁻¹). The test results showed that the thermal decomposition temperature and the critical temperature of thermal explosion were lower than for RDX alone by 46.8 and 40.69 ℃, respectively. The activation energy of the C/RDX composite was lower than those of raw RDX and a C/RDX physical mixture, indicating that the C/RDX composite exhibited high thermolysis activity.

2

Analiza możliwości zastosowania materiałów nanokrystalicznych w energoelektronice

Biskup Tomasz, Kołodziej Henryk, Paluszczak Dariusz, Sontowski Jacek, Michalak Jarosław

Maszyny Elektryczne : zeszyty problemowe

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2021

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Nr 1 (125)

77--83

PL

W artykule przedstawiono analizę możliwości zastosowania nowoczesnych, nanokrystalicznych materiałów magnetycznych w przekształtnikach energoelektronicznych. Wyodrębniono dwa obszary zastosowań. Pierwszy z nich to elementy filtrów LCL pozwalających na kształtowanie prądu w układach prostowników aktywnych, z jednoczesną poprawą niekorzystnego wpływu takich przekształtników na sieć zasilającą. Drugi obszar to transformatory podwyższonej częstotliwości w układach przetwarzania energii, zwłaszcza ładowarkach akumulatorów dużej mocy. W obu tych przypadkach zastosowanie materiałów nanokrystalicznych mogłoby poprawić właściwości układów przez redukcję wymiarów, zmniejszenie strat czy hałasu. Zaproponowano także dwa stanowiska testowe pozwalające na weryfikację wyżej przedstawionej tezy.

EN

The paper presents an analyses of possible application the modern nanocomposite materials in the power electronics. The applications area was divided into the two subsystems. The first application is input LCL filters in active front end converters for energy recuperation. The second one is HF transformers for DC/DC converters, mainly in high power battery chargers. In the both application area the nanocomposite materials could improve its properties by mass and noise reduction or higher efficiency of energy conversion. In the end of the paper the two setups was proposed which can proof the thesis.

3

The MWCNTs-Rh Nanocomposite Obtained By The New High-Temperature Method

Dobrzańska-Danikiewicz A. D., Cichocki D., Łukowiec D.

Archives of Metallurgy and Materials

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2015

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Vol. 60, iss. 2A

1057--1063

EN

A nanocomposite was fabricated during the research undertaken, consisting of multiwalled carbon nanotubes coated with rhodium nanoparticles by the new high-temperature method being the subject of the patent claim. High quality multiwalled carbon nanotubes (MWCNTs) with the length of 100÷500 nm and the diameter of 8÷20 nm obtained in advance with Catalytic Chemical Vapour Deposition (CVD) were employed in the investigations. The nanotubes manufactured under the own research contain small amounts of metallic impurities and amorphous carbon deposits. Multiwalled carbon nanotubes functionalisation in acids was applied to deposit rhodium nanoparticles onto the surface of carbon nanotubes, and then the material was placed in a solution being a precursor of rhodium nanoparticles. The material prepared was next placed in a quartz vessel and subjected to high-temperature reduction in the atmosphere of argon to deposit rhodium nanoparticles onto the surface of multiwalled carbon nanotubes. The following examinations were performed, respectively: MWCNTs fabrication, fabrication of a CNT-NPs (Carbon NanoTube-NanoParticles) nanocomposite material; the characterisation of the materials produced including examination of the structure and morphology, and the assessment of rhodium nanoparticles distribution on the surface of carbon nanotubes. Micro- and spectroscopy techniques were employed to characterise the structure of the nanocomposites obtained.

PL

W ramach wykonanych badań wytworzono nanokompozyt składający się z wielościennych nanorurek węglowych pokrytych nanocząsteczkami rodu nową wysokotemperaturową metodą, będącą przedmiotem zgłoszenia patentowego. W badaniach wykorzystano wysokiej jakości wielościenne nanorurki węglowe MWCNTs o długości 100÷500 nm i średnicy 8÷20 nm uprzednio otrzymane w procesie katalityczno-chemicznego osadzania z fazy gazowej (CCVD). Wytworzone w ramach prac własnych nanorurki zawierają nieznaczne ilości zanieczyszczeń metalicznych i amorficznych depozytów węglowych. W celu osadzenia nanocząsteczek rodu na powierzchni nanorurek węglowych zastosowano funkcjonalizację wielościennych nanorurek węglowych w kwasach, następnie materiał umieszczono w roztworze będącym prekursorem nanocząsteczek rodu. Przygotowany materiał umieszczono w dalszej kolejności w kwarcowym naczyniu i poddano redukcji wysokotemperaturowej w atmosferze argonu w celu osadzenia nanocząsteczek rodu na powierzchni wielościennych nanorurek węglowych. Wykonane badania obejmują kolejno: wytworzenie MWCNTs, wytworzenie materiału nanokompozytowego typu nanorurki węglowe – nanocząsteczki (CNT-NPs), scharakteryzowanie wytworzonego materiału obejmujące badanie jego struktury i morfologii oraz ocenę rozmieszczenia nanocząsteczek rodu na powierzchni nanorurek węglowych. Dla scharakteryzowania struktury otrzymanych nanokompozytów zastosowano techniki mikro- i spektroskopowe.

4

Degradation of nanoclay-filled polylactide composites

Rapacz-Kmita A., Stodolak-Zych E., Dudek M., Szaraniec B., Rozycka A., Mosialek M., Mandecka-Kamien L.

Physicochemical Problems of Mineral Processing

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2013

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Vol. 49, iss. 1

91--99

EN

Nanoclay-filled polylactide (PLA 3051D) composite materials were tested in this study and their capacity for degradation was investigated. Activated and lyophilized smectite clay was used. The filler, its morphology, and grain size distribution were characterized by the use of transmission electron microscopy, scanning electron microscopy, and the dynamic light scattering technique. Samples of pure polylactide and polylactide filled with 3% wt., 5% wt., and 10% wt. of nanoclay in subsequent series were obtained by injection molding. The optimum amount of the filler in the nanocomposites was evalu-ated based on an assessment of mechanical properties as well as capacity to degrade. The 3% wt. mass fraction of nanofiller in the polylactide matrix was found to be the most effective in enhancement of both tensile strength (RM) and Young’s Modulus (E). It was also reported that polylactide nanocomposites filled with 3% wt. of smectite clay were characterized by the highest decrease in molecular mass of the matrix polymer after degradation tests (6 weeks incubation in water at 80°C). The observed decrease in degradation time and the overall changes distinguished in the nanocomposite structure suggest the poten-tial for application of the material in the packaging industry.

5

Magnetic properties and surface domain structure of (Nd0.85Dy0.15)10Fe83Zr1B6 thin ribbons

Ceglarek A, Plusa D, Dospial M, Nabialek M, Wieczorek P

Optica Applicata

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2013

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Vol. 43, nr 1

117--122

EN

In this paper, the nanocrystalline (Nd0.85Dy0.15)10Fe83Zr1B6 ribbons produced by melt-spinning have been investigated by the X-ray diffraction method (XRD), vibrating sample magnetometer (VSM) and magnetic force microscopy (MFM). The XRD studies showed that material investigated was mainly composed of Re2Fe14B and α-Fe phases with fine grain sizes of 25 and 9 nm, respectively. The magnetic parameters determined from the hysteresis loop measurements are as follows: μ0HC = 0.96 T, μ0MR = 0.76 T, μ0MS = 1.09 T, (BH)max = 88 kJ/m3. The large remanence ratio (μ0MR/μ0MS) of 0.7 results from the exchange coupling between the soft and hard magnetic grains. The large surface interaction domains revealed by MFM confirmed the existence of strong exchange coupling between nanosize grains.

6

Vibrational spectroscopy investigation of montmorillonite-chitosane nanocomposite materials

Paluszkiewicz C., Stodolak E.

Engineering of Biomaterials

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2011

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Vol. 14, no. 109-111 spec. iss.

44

EN

Biomaterials basing on natural polysaccharides, i.e. hiauronic acid, alginate, chitosane are an alternative for already applied bioresorbable synthetic materials basing on synthetic polyhydroxy acids. Their main advantages are good accessibility, low cost, easy forming and high biocompatibility. Additionally , they are a perfect matrix for bioactive nanoparticles i.e. hydroxy apatite (HAp), tricalcium phosphate (TCP) and silica (SiO2). The work presents results of research on nanocomposite consisting of chitosane matrix (CS) modified with a nanofiller, which was natural montmorillonite (MMT). Nanocomposite foils were produced by the casting method. In order to induce better biocompatibility, the surface of the CS/MMT composite was neutralized (bath in NaOH solution). The nanocomposite foils were subjected to a bioactivity test by incubation in SBF at 37oC for 7 days. It was observed that the CS/ MMT material surface showed a local supersaturation, which was a result of apatite nucleation. The CS/ MMT nanocomposites were investigated using FT-IR ( Fourier Transform Infrared Spectroscopy) and Fourier Raman Spectroscopy. FTIR measurements o f the samples were carried out on the transmission and reflection modes. The FTIR microscopy spectra were collected using BioRad Excalibur with ATR attachment as well as microscope UMA500 equipped with MCT detector. Spectra were measure at 4 cm -1 resolution in the region from 4 000 cm -1 to 600 cm -1 . FT-Raman spectra were obtained using a FTS 6000 Bio-Rad spectrometer with Ge detector. The samples were excited with a Nd-YAG laser (1064nm). Additional all materials in all steps experiments were observed under Scanning Electron Microscopy (Nova Nano SEM). Vibrational spectroscopy methods (FT Raman and FTIR) can be used for investigation of nanocomposite foils basing on biopolymers. High sensitivity the applied spectroscopy techniques show that in the result of the neutralization of CS/ MMT foil (via incubation in NaOH solution the biopolymer chain breaks. This phenomena is visible by intensity ratio between COC/COH bands. Increase of reactivity of chitosane chain lead to entrapment of PO4+3-, which is the origin of the apatite forms nucleation process. Chemical treatment of the nanocomposite foils, i.e. NaOH washes in fluences their chemical structure and microstructure. Neutralisation of the foils is the first processing stage which precedes the potential use o fCS/ MMT foils in biomedical applications. The materials show a tendency to apatite crystallisation which may support regeneration of damaged bone tissue. The applied spectroscopic methods allowed to observe changes in the whole volume of the sample. Individual ATR measurements taken at various spectral ranges and penetration depths allow to observe subtle changes in the polymer matrix caused by chemical treatment (NaOH and SBF incubation). Results of the investigations indicate that in the CS/ MMT systems new chemical bonds and related to them vibrations appear. Quantity and quality of the interact ions is related to characteristics of the nanoparticle and the presence of forming apatite structures.

7

Vibrational spectroscopy investigation of montmorillonite - chitosane nanocomposite materials

Paluszkiewicz C., Stodolak E.

Engineering of Biomaterials

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2010

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Vol. 13, no. 99-101

128

EN

Biomaterials basing on natural polysaccharides, i.e. hiauronic acid, alginate, chitosane are an alternative for already applied bioresorbable synthetic materials basing on synthetic polyhydroxyacids. Their main advantages are good accessibility, low cost, easy forming and high biocompatibility. Additionally, they are a perfect matrix for bioactive nanoparticles i.e. hydroxyapatite (HAp), tricalcium phosphate (TCP) and silica (SiO2). The work presents results of research on nanocomposite consisting of chitosane matrix (CS) modified with a nanofiller, which was natural montmorillonite (MMT). Nanocomposite foils were produced by the casting method. In order to induce better biocompatibility, the surface of the CS/MMT composite was neutralized (bath in NaOH solution). The nanocomposite foils were subjected to a bioactivity test by incubation in SBF at 37oC for 7 days. It was observed that the CS/MMT material surface showed a local supersaturation, which was a result of apatite nucleation. The CS/MMT nanocomposites were investigated using FT-IR (Fourier Transform Infrared Spectroscopy) and Fourier Raman Spectroscopy. FTIR measurements of the samples were carried out on the transmission and reflection modes. The FTIR microscopy spectra were collected using Bio-Rad Excalibur with ATR attachment as well as microscope UMA500 equipped with MCT detector. Spectra were measured at 4 cm-1 resolution in the region from 4000 cm-1 to 600 cm-1. FT-Raman spectra were obtained using a FTS6000 Bio-Rad spectrometer with Ge detector. The samples were excited with a Nd-YAG laser (1064nm). Additional all materials in all steps experiments were observed under Scanning Electron Microscopy (Nova NanoSEM). Vibrational spectroscopy methods (FT Raman and FTIR) can be used for investigation of nanocomposite foils basing on biopolymers. High sensitivity the applied spectroscopy techniques show that in the result of the neutralization of CS/MMT foil (via incubation in NaOH solution) the biopolymer chain breaks. This phenomena is visible by intensity ratio between COC/ COH bands. Increase of reactivity of chitosane chain lead to entrapment of PO43-, which is the origin of the apatite forms nucleation process. Chemical treatment of the nanocomposite foils, i.e. NaOH washes influences their chemical structure and microstructure. Neutralisation of the foils is the first processing stage which precedes the potential use of CS/MMT foils in biomedical applications. The materials show a tendency to apatite crystallisation which may support regeneration of damaged bone tissue. The applied spectroscopic methods allowed to observe changes in the whole volume of the sample. Individual ATR measurements taken at various spectral ranges and penetration depths allow to observe subtle changes in the polymer matrix caused by chemical treatment (NaOH and SBF incubation). Results of the investigations indicate that in the CS/ MMT systems new chemical bonds and related to them vibrations appear. Quantity and quality of the interactions is related to characteristics of the nanoparticle and the presence of forming apatite structures.

8

Biocompatibility of hybrid fibrous materials basing on poly-L/DL-lactide

Stodolak E., Ścisłowska-Czarnecka A., Błażewicz M., Bogun M., Mikolajczyk T., Menaszek E.

Engineering of Biomaterials

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2010

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Vol. 13, no. 99-101

110

EN

Hybrid biomaterials due to their unique structure may become an alternative for many popular composite and nanocomposite materials. Multilevel modification of their matrix manifesting itself in the presence of particles of different sizes i.e., micrometric, submicrometric and nanometric together with the variety of shapes of a modyfing phase (nanometric fibres, submicron particles, coated nanoparticles) and its different chemical character make the hybrid materials similar to natural tissue. Bone tissue structure is particulary close to this model in which collagen fibres and hydroxyapatite particles and nanoparticles have not only different form but first of all they play different role in the tissue which depends on their chemical nature. In the biomedical engineering syntetic hybride biomaterials are usually produced using resorbable and degradable polymer matrices and inorganic filers (ceramic bioactive particles; HAp, TCP, SiO2) or organic filers (collagen, polysaccharides e.g. alginate fibres). The main function of the modyfing phase is inprovement of the polymer matrix leading to bioactive, stronger material showing high biofunctionality. Production of hybrid materials is based mainly on experimental works, which is related to the presence in their matrix few phases with different properties which may interact. Hybrid materials do not follow the rule of mixtures thus it is difficult to predict behaviour of a material in which co-exis different chemical and phisical phases. In the work hybrid composite foils were produced in which modyfing phase consisted in; nanocomposite calcium alginate fibres modyfied with ceramic nanoparticles; HAp (CAH fibres), TCP (CAT fibres), SiO2 (CAS fibres) and MMT (CAM fibres). Short fibres were subjected to additional size reduction in vibration ball mill resultiong in submicron and nanometric phases. Size of the particels after grinding was determined by screening analysis and DLS method (for particels smaller than 500 nm). It was observed than the population of short fibres consist in three fractions i.e.; micrometric (~2μm, 50 wt.%), submicrometric (500–800 nm, 40 wt.%) and nanometric ( below 500 nm, 10 wt.%). The fibres and products of their grinding were homogenised in P(L/ DL)LA polymer solution (poly-L/DL-lactide, Purarorb 80, Purac Germany). A hybride material in the form of thin foils containing 2 wt.% of a modyfing phase were subjected to durability tests consisting in incubation in distilled water (30 days/37C). Monitoring of the medium pH and conductivity did not show changes related to harmful products of their decomposition. Osteoblast-like cells from MG-63 line contacted with the surface of the materials showed high viability (MMT test) comparable with the reference material (TCPS). High degree of adherence of the cells to the materal surface (CV test) testifies of potential abilities of the material stimulating proliferation of bone tissue cells. The highes rate of dynamic growth (increase of the cells number after 7 days of incubation) was observed for the material which was modified with CAS fibres and products of their grinding. The performed investigations have a preliminary character. Their results testify for potential osteoconductive or osteoinductive abilities of hybride materials basing on P(L/DL)LA and alginate nanocomposite fibres.

9

Otrzymywanie i ocena właściwości nanokompozytów PVC/MMT wytwarzanych metodą rozpuszczalnikową

Pagacz J., Pielichowski K.

Czasopismo Techniczne. Chemia

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2009

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R. 106, z. 1-Ch

95-110

PL

W niniejszym artykule opisano preparatykę i analizę nanokompozytów PVC/MMT wytwarzanych metodą rozpuszczalnikową. Stosowano suspensyjny PVC i nanonapełniacze - naturalny oraz organicznie modyfikowany montmorylonit, a także, jako rozpuszczalnik, cykloheksanon. W celu scharakteryzowania struktury otrzymanych materiałów wykorzystano spektroskopię FTIR oraz metodę WAXD, natomiast wpływ nanonapełniacza na stabilność termiczną nanokompozytów PVC/MMT sprawdzano metodą termograwimetryczną (TG).

EN

In this work results of preparation and analysis of PVC/MMT nanocomposites were presented. The nanocomposites were obtained by the solution casting method, using suspensive PVC and nanofillers - the natural and organically-modified montmorillonite. Cyclohexanone was used as a solvent. The structure of nanomaterials obtained was studied by FTIR and WAXD methods. Thermal stability of PVC/MMT nanocomposites was characterized using thermogravimetric method (TG).

10

Nowe materiały dla bezpilotowych aparatów latających

Chatys R., Koruba Z., Kleinhof M.

Zeszyty Naukowe Politechniki Świętokrzyskiej. Mechanika

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2004

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Z. 80

77-83

PL

W artykule przedstawione są rozważania na temat możliwości zastosowania w mikrobezpilotowym aparacie latającym (MBAL) nowych materiałów konstrukcyjnych. Zostały zamodelowane fizyko-mechaniczne własności komponentów kompozytu węglowego PAN i nanokompozytu poprzez metodę statystyczną.

EN

In the paper are presented the considerations on the possibilities of using In micro unmanned serial vehicle (MUAV) of new materials construction. The authors reveal the interdependence of the components of the PAN carbon composite and nanocomposite in the statistical aspects by studying the physical and mechanical properties of the components