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Ethylmorphine is permitted internationally for therapeutic purposes where morphine is not indicated across the globe. Nor-ethylmorphine a major metabolite of ethylmorphine. To differentiate the intake of morphine from ethylmorphine, nor-ethylmorphine stable reference material is desirable. There is no available commercial source and no data for reference material context for this substance. Therefore, nor-ethylmorphine HCl was synthesized and characterized, and purity and potency were assessed using nuclear magnetic resonance (NMR), high-resolution mass spectrometry (HRMS), Fourier transform infrared spectroscopy (FT-IR), thermogravimetry (TGA), and high-performance liquid chromatography (HPLC). Purity and potency were found to be 98.29% and 96.40%, respectively, providing a fit for purpose reference material for doping control analysis in sports.

A stationary phase based on sub-2 μm ground silica monolith particles was fabricated by in situ polymerization and applied in micro-column for separation of peptides. The sub-2 μm silica particles were obtained from monolith using sol-gel process followed by grinding and sedimentation to remove the fines. Initially, the silica monolith particles were pretreated with 3-trimethoxysilyl propyl methacrylate to attach double-bonded ligands onto the surface, then a network structure was formed onto the surface of the particle using styrene, N-isopropylacrylamide, and ethylene glycoldimethacrylate. The effect of the flow rate of the mobile phase on the separation performance was investigated. The stationary phase was characterized by field emission scanning electron microscopy, thermogravimetry, particle size distribution, and element analysis. The resultant phase was packed in glass-lined stainless steel micro-columns (2.1 mm × 50 mm) and evaluated for fast separation. An average number of theoretical plates as high as 9800 plates/column (5.10 μm plate height) was achieved for five synthetic peptides under the optimized flow rate of 0.15 mL/min. The repeatabilities of column-to-column, intraday, and interday through relative standard deviation were found better than 4%, exhibiting satisfactory repeatability of the developed micro-column for fast separation of peptides.

The separation of ethane-ethylene mixtures was evaluated using two zeolitic imidazolate frameworks, which are only different from the assemble metal, as stationary phase from inverse gas chromatography data. The chromatographic profiles exhibited peaks adequately resolved. Separation is attributed to the pore sizes of the adsorbents that discern between ethane and ethylene molecule shapes and closed kinetic diameters. The adsorption heats were estimated for each probe molecule from the slopes of the straight lines at four temperatures. The evaluated materials are iso-structural compounds with the unique difference of assembling metal (cobalt and zinc). Cobalt material showed atypical adsorption of ethane over ethylene, which was observed taking into account the retarded elution of the paraffin. Therefore, the anomalous behavior could be ascribed to the presence of cobalt(II). Structural characterization of both materials was performed by X-ray powder diffraction, X-ray photoelectronic spectroscopy, and thermogravimetry, while morphological characterization was performed by scanning electron microscopy. H2 -CO2 and CH4 -CO2 mixtures separation were also evaluated by inverse gas chromatography. Both materials were able to separate these two mixtures. CO2 was the highest retained probe molecule due to the presence of quadrupole moment.

Thermogravimetry (TG) combined with electrospray and atmospheric chemical ionization (ESI+APCI) mass spectrometry (MS) was developed to rapidly characterize thermal decomposition products of synthetic polymers and plastic products. The ESI-based TG-MS method is useful for characterizing thermally labile, nonvolatile, and polar compounds over an extensive mass range; and the APCI-based TG-MS counterpart is useful for characterizing volatile and nonpolar compounds. Both polar and nonpolar compounds can be simultaneously detected by ESI+APCI-based TG-MS.Analytes with different volatility were produced from TG operated at different temperatures, which were delivered through a heated stainless-steel tube to the ESI+APCI source where they reacted with the primary charged species generated from electrospray and atmospheric pressure chemical ionization (ESI+APCI) of solvent and nitrogen. The analyte ions were then detected by an ion trap mass spectrometer.A semi-volatile PEG 600 standard was used as the sample and protonated and sodiated molecular ions together with adduct ions including [(PEG)n + 15]The information obtained from the TG-ESI+APCI-MS analysis is useful in rapidly distinguishing different types of polymers and their products. In addition, the signals of the additives in the polymer products, including antioxidants and plasticizers, were also detected before the TG temperature reached T

Novel poly(vinyl alcohol)/chondroitin sulfate (PVA/CS) composite hydrogels containing hydroxyapatite (HA) or Sr-doped HA (HASr) particles were synthesized by a freeze/thaw method and characterized aiming towards biomedical applications. HA and HASr were synthesized by a wet-precipitation method and added to the composite hydrogels in fractions up to 15 wt%. Physical-chemical characterizations of particles and hydrogels included scanning electron microscopy, energy-dispersive spectroscopy, Fourier-transform infrared spectroscopy, X-ray diffraction, thermogravimetry, porosity, compressive strength/elastic modulus, swelling degree, and cell viability. Particles were irregular in shape and appeared to have narrow size variation. The thermal behavior of composite hydrogels was altered compared to the control (bare) hydrogel. All hydrogels exhibited high porosity. HA/HASr particles reduced total porosity without reducing pore size. The mechanical strength was improved as the fraction of HA or HASr was increased. HASr particles led to a faster water uptake but did not interfere with the total hydrogel swelling capacity. In cell viability essay, increased cell growth (above 120%) was observed in all groups including the control hydrogel, suggesting a bioactive effect. In conclusion, PVA/CS hydrogels containing HA or HASr particles were successfully synthesized and showed promising morphological, mechanical, and swelling properties, which are particularly required for scaffolding.

SrBPO5 :Eu2+ -Eu3+ phosphors were synthesized using a conventional solid self-reduction reaction in an air atmosphere. Samples were characterized using thermogravimetry analysis (TGA), differential scanning calorimetry (DSC), X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectra, fluorescence spectra and Commission International de l'Eclairage (CIE) data. The results of TGA and DSC showed that the raw materials could completely react at 1000°C. FTIR spectra and XRD results displayed that europium ions of different concentrations do not effect the structure of the hosts. Fluorescence spectra displayed that europium ions exist in bivalent and trivalent forms, and that the emission peak at 403 nm was attributed to the typical 5d-4f transition for Eu2+ ; 597 nm and 620 nm emissions were assigned to the characteristic transitions of 5 D0 -7F1, 2 for Eu3+ . CIE results depicted that the colour tone of the phosphors could be macro-controlled from blue to purple by controlling the doping amount of Eu3+ .Therefore, relative luminescence intensity between Eu2+ and Eu3+ could be adjusted by controlling the doping concentration of europium to tune the luminescence colour of SrBPO5 .

Background The aim of this study is to characterize and detect the possible differences among the hair of three different ethnicities: African, Asiatic and Caucasian. Materials and Methods The differences in water adsorption/desorption behaviour of hairs were studied using a thermogravimetric balance and compared with the analysis of the lipid distribution and order using synchrotron‐based Fourier transform infrared microspectroscopy. Besides, the thermal thermogravimetry (TG) and differential scanning calorimetry (DSC) analyses on human hair were executed. Results Differences in the diffusion coefficients were evidenced. African hair exhibited increased permeability. Caucasian hair displayed a higher water absorption capability with increasing humidity but with a slow diffusion rate. The Asian fibre appeared to be more resistant to hydration changes. The spectroscopic analysis showed notable differences in the cuticle lipids. The African cuticle exhibited more lipids with a lower order bilayer. The outmost layer of Caucasian fibres contained more ordered lipids, and the Asian fibres show a very low level of lipids on the cuticle region. The DSC results indicate no difference in the thermal stability and TG showed higher water content in the Caucasian fibre and a possible lower cysteine disulphide bond content in the African hair matrix. Conclusion The triple approach demonstrated the permeability differences among the ethnic fibres and their correlation with the properties of their cuticle lipids. These differences could have particular relevance to the hair care cosmetic market., The authors wish to thank the 2009 SGR 2012 (AGAUR) for providing support. FTIR microspectroscopy was performed on the MIRAS beamline at the ALBA Synchrotron in collaboration with ALBA staff. Additionally, the authors acknowledge the Service of Dermocosmetic Assessment for its collaboration and the technical support provided by Isabel Yuste.

Background Potato protein (PP) has promising potential for utilization in food applications due to its high nutritive value and functional properties. Grapeseed oil (GO) is rich in unsaturated fatty acids and antioxidant active ingredients. However, its application is limited because of low stability and high volatility. In order to overcome such problems, PP-based microcapsules encapsulating GO were produced by complex coacervation, and characterized using optical, thermodynamic and spectroscopic analyses. Results Results indicated that a ratio of GO/PP of 1:2 led to the best encapsulation effect with the maximum microencapsulation efficiency and yield. Intact and nearly spherical microcapsules were observed from scanning electron microscopy images. Results of thermogravimetry demonstrated that thermal resistance was increased in the microencapsulated GO, indicating that PP-based microcapsules could be a good way to protect the thermal stability of GO. Fourier transform infrared spectra indicated that hydrogen bonding and covalent crosslinking might occur among wall materials, but a physical interaction between GO and wall materials. Conclusions PP can be successfully used to encapsulate GO when combined with chitosan, indicating that PP-based microcapsules have potential for application in encapsulating liquid oils with functional properties. A schematic diagram of possible interactions was constructed to better understand the mechanism of formation of the microcapsules. © 2020 Society of Chemical Industry.

The pyrolysis and catalytic reforming process of waste plastics are the best pathways to handle vast amounts of waste plastics as they can convert these waste polymers into sustainable products. This study aims to incorporate a natural-clay-mineral (NCM) with LaFeO3 nanoparticles, with the LaFeO3/NCM catalyst in the pyrolysis of polypropylene (PP) being used as an example of plastic waste. The decomposition of PP with and without catalyst has been theoretically studied using thermogravimetry (TG) and differential scanning calorimetry (DSC) measurements under atmospheric pressure and nitrogen atmosphere. The TG/DSC results show that (i) the required temperature for pyrolysis of PP with or without catalyst in a practical system ranges from 460°C to 480°C; (ii) the amount of coke produced on the surface of the NCM or LaFeO3 is about 2 wt.% compared with the initial plastic levels; (iii) with the catalyst, PP not only goes through the phase transitions of solid to liquid to gas but also decomposition and combination processes between components from the hydrocarbon chain scission of PP. Gas chromatography–mass spectrometry (GC–MS) results show significant differences in the fuel oil recovered from the pyrolysis and catalytic reforming process. In the presence of the catalyst, cracking components consist of 49.3% alkenes (branched-chain alkenes, cyclo-alkenes, and alkenes) and 34.4% alkanes, while without the catalyst, branched-chain alkenes were up to 90.2%. Repeated pyrolysis and GC–MS investigations demonstrated the reusability of the LaFeO3/NCM catalyst, which is promising for its recycling and the efficient pyrolysis of PP.

[SnI8{Fe(CO)4}4][Al2Cl7]2 contains the [SnI8{Fe(CO)4}4]2+ cation with an unprecedented highly coordinated, bicapped SnI8 prism. Given the eightfold coordination with the most voluminous stable halide, it is all the more surprising that this SnI8 arrangement is surrounded only by fragile Fe(CO)4 groups in a clip‐like fashion. Inspite of a predominantly ionic bonding situation in [SnI8{Fe(CO)4}4]2+, the I−⋅⋅⋅I− distances are considerably shortened (down to 371 pm) and significantly less than the van der Waals distance (420 pm). The title compound is characterized by single‐crystal structure analysis, spectroscopic methods (EDXS, FTIR, Raman, UV/Vis, Mössbauer), thermogravimetry, and density functional theory methods., You're clinging! In a clip‐like fashion, Fe(CO)4 groups surround a central SnI8 subunit in [SnI8{Fe(CO)4}4]2+, which has an unprecedentedly high coordination of tin with the most voluminous, stable halide.

The applications of a variety of bioactive ceramics such as hydroxyapatite (HA) in orthopedics are limited by their insufficient mechanical properties, especially poor fracture toughness. Thus, further extending the clinical applications of these materials warrants the enhancement of their mechanical properties. Although the reinforcement of ceramics by 2D nanomaterials has been well recognized, integrated structural, mechanical, and functional considerations have been neglected in the design and synthesis of such composite materials. Herein, we report the first use of silica-coated reduced graphene oxide (S-rGO) hybrid nanosheets to create bioceramic-based composites with simultaneously enhanced mechanical and biological properties. In the representative HA-based bioceramic systems prepared by spark plasma sintering, S-rGO incorporation was found to be more effective for increasing the Young's modulus, hardness, and fracture toughness than the incorporation of uncoated reduced GO (rGO). Furthermore, when assessed with osteoblast-like MG-63 cells, such novel materials led to faster cell proliferation and higher cell viability and alkaline phosphatase activity than are generally observed with pure HA; additionally, cells demonstrate stronger affinity to S-rGO/HA than to rGO/HA composites. The S-rGO/bioceramic composites are therefore promising for applications in orthopedic tissue engineering, and this research provides valuable insights into the fabrication of silica-coated hybrid nanosheet-reinforced ceramics. Nanyang Technological University This study was supported by Nanyang Technological University (NTU,Grant No. M4080160).

This study addresses the inherent issues surrounding surface modification methods of nanofibers and proposes an environmentally friendly and less toxic strategy for the surface modification of hydrophilic nanofiber. From the continuation of our previous work, which discussed the easy production of nanofiber (average size: 127 nm) from oil palm mesocarp fiber (OPMF), in this work, the surface of nanofibers (M‐IL‐OPMF) were modified through vapor‐phase‐assisted surface polymerization (VASP) to improve the affinity of interface between the polymer grafted M‐IL‐OPMF and non‐polar matrix. VASP of e‐caprolactone was successfully proceeded from the [M‐IL‐OPMF] at 70 °C for 24 h and 72 h, and compositions were estimated to be 35.7% fiber/64.3% polymer and 27.8% fiber/72.2% polymer. To confirm the grafting of PCL, size‐exclusion chromatography (SEC) and Fourier transform infrared (FT‐IR) spectroscopy, thermogravimetry (TG), and dispersibility test in hydrophobic solvent were carried out. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 2575–2580

Gelatin/chitosan/polyvinyl alcohol hydrogels were fabricated at different polymer ratios using the freeze-drying and sterilized by steam sterilization. The thermal stability, chemical structure, morphology, surface area, mechanical properties, and biocompatibility of hydrogels were evaluated by simultaneous thermal analysis, Fourier transform infrared spectroscopy, X-ray diffraction, confocal microscopy, adsorption/desorption of nitrogen, rheometry, and 3-4,[5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide cell viability assay (MTT assay), respectively. The samples showed a decomposition onset temperature below 253.3 ± 4.8°C, a semicrystalline nature, and a highly porous structure. Hydrogels reached the maximum water uptake in phosphate-buffered saline after 80 min, showing values from nine to twelve times their dry mass. Also, hydrogels exhibiting a solid-like behavior ranging from 2,567 ± 467 to 48,705 ± 2,453 Pa at 0.1 rad/s (low frequency). The sterilized hydrogels showed low cytotoxicity (cell viability > 70%) to the HT29-MTX-E12 cell line. Sterilized hydrogels by steam sterilization can be good candidates as scaffolds for tissue engineering applications.

Analysis of soil properties and soil organic matter dynamics requires the use of reliable and rapid analytical techniques. Included in such applicable techniques is thermogravimetry (TG) which, typically, measures mass losses of soil heated during a temperature ramping. Previous work revealed relationships between mass losses of 10°C intervals (TG indicators) and total organic carbon (SOC), total nitrogen (TN) and clay content, and relationships between mass losses of larger temperature intervals (TG fractions) and interactions between SOC, TN and clay. However, widespread application of these relationships is hampered by the requirement to equilibrate soils at 76% relative humidity (RH) prior to and during TG measurements. In this study we tested whether the relationships between mass losses and soil properties can be observed at 43% RH by analyzing 37 mostly arable and grassland soils. It was found that at 43% RH the same TG indicators correlated significantly with soil properties as at 76% RH, but the correlations with TN and clay contents were observed at lower temperatures. New equations were developed for rapid analysis of soil properties using TG indicators and for determination of TG fractions at 43% RH. The results indicated that for routine application of these TG approaches in soil science, it is necessary to include an RH parameter that accounts for potential shifts in diagnostic temperatures when modelling the relationships between TG data and soil properties. HIGHLIGHTS: Thermogravimetry data correlate with soil organic carbon, nitrogen and clay at 43% RH. Clay and nitrogen correlated at lower temperature compared to 76% RH. New equations applicable at laboratory conditions were developed. Wider use of TG requires including information on ambient moisture.

One of the main challenges in the design of scaffolds for cortical bone regeneration is mimicking the highly oriented, hierarchical structure of the native tissue in an efficient, simple, and consistent way. As a possible solution to this challenge, positive replica based on electrophoretic deposition (EPD) was here evaluated as a technique to produce organic/inorganic scaffolds with oriented micro-porosities mimicking Haversian canals diameter and spacing. Two different sizes of 45S5 bioactive glass (BG) powders were chosen as inclusions and loaded in a chitosan matrix via EPD on micro-patterned cathodes. Self-standing chitosan scaffolds, with a homogeneous dispersion of BG particles and regularly-oriented micro-channels (ϕ = 380 ± 50 μm, inter-channel spacing = 600 ± 40 μm), were obtained. In vitro analysis in simulated body fluid (SBF) revealed the ability to induce a deposition of a homogenous layer of hydroxyapatite (HA), with Ca/P nucleation reactions appearing kinetically favored by smaller BG particles. Cell interaction with hybrid scaffolds was evaluated in vitro with bone osteosarcoma cells (SAOS-2). The osteoconductive potential of EPD structures was assessed by evaluating cells proliferation, viability and scaffold colonization. Results indicate that EPD is a simple yet extremely effective technique to prepare composite micro-patterned structures and can represent a platform for the development of a new generation of bone scaffolds. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2019.

A novel and efficient heterogeneous CuSO4 nanoparticles (CuSO4 NPs) immobilized on carboxymethylcellulose/polyaniline (CuSO4NPs@CMC/PANI) composites were prepared via one-pot and one-step interfacial oxidative polymerization of aniline with sodium carboxymethylcellulose (CMC) as soft template and CuSO4 as catalyst. The in situ formed CuSO4 NPs were dispersed uniformly and firmly on the resultant composites and stabilized by complexation with hydroxyl groups (─OH), carboxylate groups (─COO−), nitrogen atoms, and delocalized π-π conjugate benzenoid and quinoid moieties of CMC/PANI composites. The morphology, composition, and structure of the as-fabricated composites were systematically characterized by X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), and derivative thermogravimetry (DTG) techniques. The CuSO4NPs@CMC/PANI composites were successfully applied as catalysts in aldehyde-alkyne-amine (A3) coupling reactions, A3-cycloisomerization tandem reactions, and Cu-catalyzed azide-alkyne cycloaddition (CuAAC) reactions. All reactions proceeded smoothly and afforded the desired products in excellent yields. Moreover, no significant decrease in catalytic ability was observed in A3 model reaction after 15 recycles, indicating CuSO4NPs@CMC/PANI composites exhibited easy separability and high reusability. Tolerance of wide scope of substrate, excellent catalytic activity, easy operation, recycling of catalyst, and environmental benign are the salient features of these catalytic process.

This is the peer reviewed version of the following article: Sharifi, S., Islam, M.M., Sharifi, H., Islam, R., Huq, T.N., Nilsson, P.H., ... Chodosh, J. (2021). Electron Beam Sterilization of Poly(Methyl Methacrylate)—Physicochemical and Biological Aspects. Macromolecular Bioscience, 21(4), 2000379, which has been published in final form at https://doi.org/10.1002/mabi.202000379. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions. This article may not be enhanced, enriched or otherwise transformed into a derivative work, without express permission from Wiley or by statutory rights under applicable legislation. Copyright notices must not be removed, obscured or modified. The article must be linked to Wiley’s version of record on Wiley Online Library and any embedding, framing or otherwise making available the article or pages thereof by third parties from platforms, services and websites other than Wiley Online Library must be prohibited. Electron beam (E-beam) irradiation is an attractive and efficient method for sterilizing clinically implantable medical devices made of natural and/or synthetic materials such as poly(methyl methacrylate) (PMMA). As ionizing irradiation can affect the physicochemical properties of PMMA, understanding the consequences of E-beam sterilization on the intrinsic properties of PMMA is vital for clinical implementation. A detailed assessment of the chemical, optical, mechanical, morphological, and biological properties of medical-grade PMMA after E-beam sterilization at 25 and 50 kiloGray (kGy) is reported. Fourier transform infrared spectroscopy, thermogravimetric analysis, and differential scanning calorimetry studies indicate that E-beam irradiation has minimal effect on the chemical properties of the PMMA at these doses. While 25 kGy irradiation does not alter the mechanical and optical properties of the PMMA, 50 kGy reduces the flexural strength and transparency by 10% and 2%, respectively. Atomic force microscopy demonstrates that E-beam irradiation reduces the surface roughness of PMMA in a dose dependent manner. Live-Dead, AlamarBlue, immunocytochemistry, and complement activation studies show that E-beam irradiation up to 50 kGy has no adverse effect on the biocompatibility of the PMMA. These findings suggest that E-beam irradiation at 25 kGy may be a safe and efficient alternative for PMMA sterilization.

Unformatted preprint Iongels have attracted much attention over the years as ion-conducting soft materials for applications in several technologies including stimuli-responsive drug release and flexible (bio)electronics. Nowadays, iongels with additional functionalities such as electronic conductivity, self-healing, thermo-responsiveness or biocompatibility are actively being searched for high demanding applications. In this work, we present a simple and rapid synthetic pathway to prepare hyperelastic and thermoreversible iongels. These iongels were prepared by supramolecular crosslinking between polyphenols biomolecules with a hydroxyl-rich biocompatible polymer such as poly(vinyl alcohol) (PVA) in the presence of ionic liquids. Using this strategy, a variety of iongels were obtained by combining different plant-derived polyphenol compounds such as gallic acid, pyrogallol, and tannic acid with imidazolium-based ionic liquids, namely [C2mim][N(CN)2] and [C2mim][Br]. A suite of characterization tools was used to study the structural, morphological, mechanical, rheological and thermal properties of the supramolecular iongels. These iongels can withstand large deformations (40 % under compression) with full recovery, revealing reversible transitions from solid to liquid state between 87 to 125 °C. Finally, the polyphenol-based thermoreversible iongels shows appropriated properties for their potential application as printable electrolytes for bioelectronics. This work was supported by Marie Sklodowska-Curie Research and Innovation Staff Exchanges (RISE) under the grant agreement No 823989 “IONBIKE”. Also, the financial support received from CONICET, UNL, and ANPCyT (all of Argentina) is gratefully acknowledged. Liliana C. Tomé has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement no. 745734.

Ethanolamine (MEA) solution is the most commonly used commercial chemical absorbent in conventional CO2 postcombustion processes; however the high heat duty and reaction temperature (e.g. 125°C) for solvent regeneration leads to high energy requirements (approximately 70–80% of the total running cost). This paper reports a catalytic solvent regeneration of a CO2‐loaded MEA solution using industrial calcined rough metatitanic acid (TiO(OH)2) as the catalyst to improve the CO2 desorption rate and reduce the regeneration temperature to 95°C. The catalytic reaction parameters were systematically investigated with an improvement in the CO2 desorption rate of 28.9% in comparison with the non‐catalytic process. The results of characterization, such as the thermogravimetry analysis, X‐ray diffraction, N2 adsorption‐desorption, pyridine‐infrared spectroscopy (Py‐IR), showed that the Lewis acid of the industrial metatitanic acid played a major role in the decomposition of carbamate and in enhancing the regeneration rate of MEA solvent in a CO2‐rich MEA solution. © 2018 Society of Chemical Industry and John Wiley & Sons, Ltd.

Tento článek kriticky analyzuje tradiční metodu kinetického stanovení aktivační energie parciálním dělením ploch měřeného píku diferenciální termické analýzy. Tento postup je nesprávný, protože chybí odezva tepelné setrvačnosti, která mění tvar základní linie píku z přímého na s-tvar. Tento účinek je znám již od Newtonova zákona o chlazení, ale výsledné chyby přetrvávají ve všech kinetických metodách založených na neisotermických termoanalytických měřeních. Pokud jde o kalorimetrii, je to už ověřené, protože tepelná setrvačnost se stala standardní součástí stanovení tepla pomocí Tianovy historické rovnice. Role a dopad tepelné setrvačnosti je diskutován a analyzován do všech podrobností. This paper critically analyzes the traditional method of kinetic determination of activation energy by sectioning the recorded differential thermal analysis peak area. This procedure is incorrect because it misses the impact of thermal inertia, which changes the shape of the peak's base line from straight to s-shape. This effect has been known since the Newton cooling law, but the resulting errors persist to be interwoven into all the kinetic methods based on nonisothermal thermoanalytical measurements. Relating to calorimetry, it is necessary here because heat inertia has become a standard part of heat determination via using the Tian historical equation. The role and impact of heat inertia is discussed and analyzed in detail.

Carbon nanospheres were prepared and functionalized with carboxyl acid groups (CNS-CA), then reacted with 3-aminopropyltriethoxysilane to introduce amino groups onto the surface (CNS-NH₂) by post-synthesis grafting. CNS-NH₂ was acidified in order to convert the amino groups (-NH₂) into ammonium moieties ( ). Various techniques such as N₂ physisorption, X-ray diffraction, Fourier transform infrared spectroscopy, Raman spectroscopy, thermogravimetry, X-ray photoelectron spectroscopy, and transmission electron microscopy were used to characterize the nanospheres. The removal of chromium ions from aqueous solution using was investigated. Factors influencing the uptake of Cr(VI) ions such as solution pH, adsorbent dose, and initial Cr(VI) ion concentration were investigated. Equilibrium adsorption data fitted the Langmuir model very well. The adsorption maximum capacity of Cr(VI) was found to be 52.38 mg/g. The reusability of results indicated that it can be reused five times successfully without loss of adsorption capacity.

This work reports the application possibilities of cobalt ferrite (CoFe2 O4 ) magnetic nanoparticles (CFMNPs) for stimuli responsive drug delivery by magnetic field induced hyperthermia technique. The CFMNPs were characterized by X-ray diffraction (XRD) with Rietveld analysis, field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED), fourier transform infrared spectroscopy (FTIR), thermogravimetry and differential thermal analysis (TG-DTA), vibrating sample magnetometer (VSM) and superconducting quantum interference device (SQUID) magnetometry. Particles were functionalized with folic acid (FA) by EDC-NHS coupling method and loaded with anticancer drug (DOX) by activated folate ions. The drug release was studied as a function of time at two different temperatures (37 and 44 °C) under pH∼5.5 and 7. It was observed that the drug release rate is higher at elevated temperature (44 °C) and acidic pH∼5.5 as compared to our normal body temperature and pH∼7 using the CFMNPs. This way, we have developed a pH and temperature sensitive drug delivery system, which can release the anticancer drug selectively by applying ac magnetic field as under ac field particles are heated up. We have calculated the amount of heat generation by the particles around 1.67 °C per second at ∼600 Hz frequency. By MTT assay on cancer cell and normal cell, it was confirmed that CFMNPs are nontoxic and biocompatible in nature, which assures that our synthesized particles can be successfully used in localized cancer treatment by stimuli responsive drug delivery technique.

Poly-(lactide-co-glycolide acid) (PLGA) has been widely investigated as scaffold material for bone tissue engineering owing to its biosafety, biodegradability, and biocompatibility. However, the bioinert surface of PLGA may fail in regulating cellular behavior and directing osteointegration between the scaffold and the host tissue. In this article, oxidized chondroitin sulfate (oCS) and type I collagen (Col I) were assembled onto PLGA surface via layer by layer technique (LbL) as an adhesive coating for the attachment of inorganic minerals. The multilayer-modified PLGA scaffold was mineralized in vitro to ensure the deposition of nanohydroxyapatite (nHAP). It was found that nHAP crystals were more uniformly and firmly attached on the multilayer-modified PLGA as compared with the pure PLGA scaffold, which remarkably improved PLGA surface and mechanical properties. Additionally, in vitro biocompatibility of PLGA scaffold, in terms of bone mesenchymal stem cells (BMSCs) attachment, spreading and proliferation was greatly enhanced by nHAP coating and multilayer deposition. Furthermore, the fabricated composite scaffold also shows the ability to promote the osteogenic differentiation of BMSCs through the up-regulation of osteogenic marker genes. Thus, this novel biomimetic composite scaffold might achieve a desirable therapeutic result for bone tissue regeneration. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 2714-2725, 2018.

High sinter density is desired in powder metallurgy components as the requirement for performance is increasing day‐by‐day. One of the promising ways to achieve improved densification during sintering is through the addition of nanopowder to the conventional micrometer sized metal powder. It is well known that the surface chemistry of the powder has a decisive effect on sintering and consequently the properties of the components produced. Extensive research has hence been conducted to elucidate the surface chemistry and its influence on sintering for powder used in conventional powder metallurgy. Nanopowder, owing to high surface to volume ratio, can contribute to the activation of sintering at lower temperatures and enhance the sinter density. In this context, the surface chemistry of the nanopowder is also expected to exhibit substantial influence on sintering. The present investigation is aimed at establishing a methodology to study the surface chemistry and oxide thickness of nanopowder. For this purpose, iron nanopowder of 3 different size fractions: 35 to 45, 40 to 60, and 60 to 80 nm with core‐shell structure were studied. Different approaches were adopted to evaluate the shell thickness of the iron nanoparticles. The methodology was developed and tried on low alloy steel nanopowder to measure oxide thickness. X‐ray photoelectron spectroscopy, thermogravimetry, and high‐resolution scanning electron microscopy techniques were used to study the nanopowder. Results from different core‐shell models for iron nanopowder were found to be consistent except in the case where depth profiling was taken into account. The results were in agreement with the values obtained from thermogavimetry‐surface area correlation.

Actinide based metal-organic frameworks (MOFs) are unique not only because compared to the transition-metal and lanthanide systems they are substantially less explored, but also owing to the uniqueness of actinide ions in bonding and coordination. Now a 3D thorium-organic framework (SCU-11) contains a series of cages with an effective size of ca. 21×24 A. Th4+ in SCU-11 is 10-coordinate with a bicapped square prism coordination geometry, which has never been documented for any metal cation complexes. The bicapped position is occupied by two coordinated water molecules that can be removed to afford a very unique open Th4+ site, confirmed by X-ray diffraction, color change, thermogravimetry, and spectroscopy. The degassed phase (SCU-11-A) exhibits a Brunauer-Emmett-Teller surface area of 1272 m2 g-1 , one of the highest values among reported actinide materials, enabling it to sufficiently retain water vapor, Kr, and Xe with uptake capacities of 234 cm3 g-1 , 0.77 mmol g-1 , 3.17 mmol g-1 , respectively, and a Xe/Kr selectivity of 5.7.

Six novel 8-hydroxyquinoline derivatives were synthesized using 2-methyl-8-hydroxyquinoline and para-substituted phenol as the main starting materials, and were characterized by 1 H nuclear magnetic resonance (NMR), mass spectrometry (MS), ultraviolet (UV) light analysis and infra-red (IR) light analysis. Their complexes with Eu(III) were also prepared and characterized by elemental analysis, molar conductivity, UV light analysis, IR light analysis, and thermogravimetric-differential thermal analysis (TG-DTA). The results showed that the ligand coordinated well with Eu(III) ions and had excellent thermal stability. The structure of the target complex was EuY1-6 (NO3 )3 .2H2 O. The luminescence properties of the target complexes were investigated, the results indicated that all target complexes had favorable luminescence properties and that the introduction of an electron-donating group could enhance the luminescence intensity of the corresponding complexes, but the addition of an electron-withdrawing group had the opposite effect. Among all the target complexes, the methoxy-substituted complex (-OCH3 ) had the highest fluorescence intensity and the nitro-substituted complex (-NO2 ) had the weakest fluorescence intensity. The results showed that 8-hydroxyquinoline derivatives had good energy transfer efficiency for the Eu(III) ion. All the target complexes had a relatively high fluorescence quantum yield. The fluorescence quantum yield of the complex EuY3 (NO3 )3 .2H2 O was highest among all target complexes and was up to 0.628. Because of excellent luminescence properties and thermal stabilities of the Eu(III) complexes, they could be used as promising candidate luminescent materials.

A polyurethane-based polymer, and a sustainable, natural resource in the form of chicken feather (keratin) fibers were combined to form a bio-composite via solvent-casting-evaporation at 0, 10, 20, 30, 40, 50, 60, and 70%·w/w. The thermo-mechanical properties of the composites were assessed using thermogravimetry, dynamic mechanical analysis, and stress-strain measurements with hysteresis loops. The uniformity of the dispersion of the feather fiber in the polyurethane matrix was investigated via macro-photography. Scanning electron microscopy of fracture surfaces was used to verify that the adhesion between fiber and polymer was effective. A molecular modeling visualization predicted the existence of hydrogen bonding between fibers and polyurethane molecules and this result was supported by Fourier transform infrared analysis of the final composites. Addition of chicken feather fibers to the polyurethane matrix was found to decrease the glass transition temperature, recovery strain and mass loss of the composites, but increase the elastic modulus, storage modulus and char level. The results demonstrate that keratin derived from what is currently a waste product from the poultry industry (with significant economic and environmental disposal costs) can effectively and cheaply improve the thermo-mechanical properties of composite materials, with potentially large environmental benefits.

Novel Ca2 B2 O5 ·H2 O:Eu3+ nanotubes, constructed with nanobelts, were prepared using a hydrothermal method. The Ca3 (BO3 )2 :Eu3+ nanobelts with a thickness of about 100 nm were made for the first time using a two-step hydrothermal process with Ca2 B2 O5 ·H2 O:Eu3+ as the precursor. The samples were characterized by energy dispersive X-ray spectroscopy, X-ray diffraction, Fourier transform infra-red spectroscopy, thermogravimetry differential thermal analysis and scanning electron microscopy. The relationship between Ca3 (BO3 )2 :Eu3+ and Ca2 B2 O5 ·H2 O:Eu3+ was also studied. Possible reaction and growth mechanisms for Ca2 B2 O5 ·H2 O:Eu3+ and Ca3 (BO3 )2 :Eu3+ were proposed. Ca3 (BO3 )2 :Eu3+ preserved the basic microstructure unit of Ca2 B2 O5 ·H2 O:Eu3+ . Both Ca2 B2 O5 ·H2 O:Eu3+ and Ca3 (BO3 )2 :Eu3+ exhibited red emissions centred at 614 nm, but the maximum excitation peaks for Ca2 B2 O5 ·H2 O:Eu3+ and Ca3 (BO3 )2 :Eu3+ differed. Ca3 (BO3 )2 :Eu3+ exhibited higher photoluminescence intensity but a lower R/O value than Ca2 B2 O5 ·H2 O:Eu3+ .

Sodium dodecyl sulfate coated amino-functionalized magnetic iron oxide nanoparticles were used as an efficient adsorbent for rapid removal and preconcentration of three important organophosphorus pesticides, chlorpyrifos, diazinon and phosalone, by ultrasound-assisted dispersive magnetic solid-phase microextraction. Fabrication of amino-functionalized magnetic nanoparticles was certified by characteristic analyses, including Fourier transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, and transmission electron microscopy. Affecting parameters on the removal efficiency were investigated and optimized through half-fractional factorial design and Doehlert design, respectively. The analysis of analytes was performed by high-performance liquid chromatography with ultraviolet detection. Under the optimum conditions, extraction recoveries for 20 ng/mL of organophosphorus pesticides were in the range of 84-97% with preconcentration factors in the range of 134-155. Replicating the experiment in above condition for five times gave the relative standard deviations

This investigation entails our continued research on calcium aluminate coated graphite for application in alumina-carbon monolithic refractories. Surface treatment of graphite flakes by a scalable sol-gel route has been utilized to develop stable bonds between ceramic phases with the functionalized graphite sheets. This study has been primarily conducted to differentiate between the coating evolution pattern at green and calcined conditions. In this regard, C-H-N analysis, differential scanning calorimetry (DSC), transmission electron microscopy (TEM), x-ray diffraction (XRD) with Rietveld analysis, Fourier transformed infrared spectroscopy (FTIR) and zeta potential studies of three kinds of graphites had been compared and critically estimated. These results were supplemented with thermogravimetry (TG), pore size distribution, oxidation resistance and scanning electron microscopy (SEM) of selected samples. A schematic outline of the work has also been proposed. An appreciable improvement of bulk density, apparent porosity and crushing strength of the respective castable has been correlated with the compatibility of the coating to the reactive matrix constituents of the refractory in wide temperature region (110-1500 degrees C).

In recent years, nonfullerene acceptors have attracted much attention, owing to their great potential for use in high-performance polymer solar cells.The ladder-type building block, pyran-bridged indacenodithiophene (PDT), was used for constructing A-D-A nonfullerene acceptors through introduction of oxygen atoms into an indacenodithiophene (IDT) unit. The synthesis of PDT is accomplished by a BBr3 -mediated tandem cyclization-deprotection reaction to construct the pyran ring. Hence, molecular acceptor PTIC was synthesized and used in a polymer solar cell device. Compared to the IDT-based acceptor, PTIC exhibits higher HOMO levels and wider optical band gap at 550-800 nm. Devices fabricated with poly[(2,6-(4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)benzo[1,2-b:4,5-b']dithiophene)-co-(1,3-di(5-thiophene-2-yl)-5,7-bis(2-ethylhexyl)-benzo[1,2-c:4,5-c']dithiophene-4,8-dione)] (PBDB-T):PTIC as the active layer give a power conversion efficiency (PCE) of 7.66 %.

Surface molecular imprinting over functionalized nanoparticles has proved to be an effective approach for construction of artificial nanomaterials for protein recognition. Herein, we report a strategy for synthesis of core–shell protein-imprinted nanoparticles by the functionalization of nano-cores with ionic liquids followed by aqueous precipitation polymerization to build thermo-responsive imprinted polymer nano-shells. The immobilized ionic liquids can form multiple interactions with the protein template. The polymerization process can produce thermo-reversible physical crosslinks, which are advantageous to enhancing imprinting and facilitating template removal. With bovine hemoglobin as a model template, the imprinted nanoparticles showed temperature-sensitivity in both dispersion behaviors and rebinding capacities. Compared with the ionic-liquid-modified core nanoparticles, the imprinted particles exhibited greatly increased selectivity and two orders of magnitude higher binding affinity for the template protein. The imprinted nanoparticles achieved relatively high imprinting factor up to 5.0 and specific rebinding capacity of 67.7 mg/g, respectively. These nanoparticles also demonstrated rapid rebinding kinetics and good reproducibility after five cycles of adsorption–regeneration. Therefore, the presented approach may be viable for fabrication of high-performance protein-imprinted nanoparticles with temperature-sensitivity. This article is protected by copyright. All rights reserved

Supported liquid membranes (SLMs) based on ionic liquids (ILs) with not only high gas permeability and selectivity, but also high stability under high pressure, are highly desired for gas separation applications. In this work, permeable and selective polyamide network (PN) layers are deposited on the surface of SLMs by utilizing the cross-linking reaction of trimesoyl chloride, which was pre-dispersed in the SLMs, and vapor of amine linkers. The vapor cross-linking method makes it easy to control the growth and aggregation of PN layers, owing to the significantly reduced reaction rate, and thereby ensuring the good distribution of PN layers on the surface of SLMs. With rational choice of amine linkers and optimization of vapor cross-linking conditions, the prepared sandwich-like PN@SLMs with ILs embedded homogeneously within polymeric matrices displayed much-improved CO2 permeability and CO2 /N2 selectivity in relation to the pristine SLMs. Moreover, those SLMs with ILs impregnated into porous supports physically displayed improved stability under high pressure after vapor cross-linking, because the PN layers formed on the surface of SLMs help prevent the ILs from being squeezed out. This interfacial engineering strategy represents a significant advance in the surface modification of SLMs to endow them with promising applications in CO2 capture.

Oxygen desorption/absorption behavior of In-substituted BaFeO3−δ [BaFe1−xInxO3−δ] was evaluated using thermogravimetry, high-temperature X-ray diffraction, and iodometry. By In substitution of 10% into BaFeO3−δ with ordered distribution of oxide ion vacancy, the structural change to cubic perovskite structure occurred, accompanied by the rearrangement of oxide ion vacancy in random and by the increase in the average valence of Fe ions. The amount of desorbed oxygen per Fe ion was enhanced by only 10% In substitution, which could be attributed to the random distribution of oxide ion vacancies. Among the In-substituted specimens with almost constant valence of Fe ion, BaFe0.9In0.1O3−δ with the highest value of Fe content exhibited the largest amount of desorbed oxygen from the lattice, indicating that this material could be regarded as a promising candidate for oxygen storage materials.

Several alkali and alkaline earth (iso)cyanurates were synthesized by simple aqueous acid-base reactions and aqueous salt metathesis reactions, respectively, yielding nine new structure types. Single-crystals could be grown and the crystal structures of Rb[H2C3N3O3]·H2O-I, Rb[H2C3N3O3]·H2O-II, Cs[H2C3N3O3]·0.5H2O, Sr[H2C3N3O3]2·4H2O, Ba3[H2C3N3O3]2[HC3N3O3]2·4H2O, Ca[HC3N3O3]·3.5H2O, Sr[HC3N3O3]·3H2O, Sr[HC3N3O3]·2H2O, and Sr2[C3N3O3]OH were elucidated by single-crystal XRD. Rb3[H2C3N3O3]3[H3C3N3O3]·4H2O, Cs[H2C3N3O3]·0.5H2O, and Sr[HC3N3O3]·2H2O were synthesized as phase pure, crystalline powders and were further characterized by powder XRD, FT-IR spectroscopy, UV/Vis spectroscopy, and thermogravimetry. Sr[HC3N3O3]·2H2O was shown to be an air- and water-resistant, cheap and easily obtained precursor for the phase-pure synthesis of Sr3[C3N3O3]2, a promising SHG material, and Sr[NCN]. Moreover, an interesting dependence of the polymeric anion structure from its protonation degree was observed.

This work reports the preparation of magnetically recyclable cuprous oxide supported on iron oxide (Cu2O-Fe3O4) nanocomposites. The prepared Cu2O-Fe3O4 nanocomposites was used as a heterogeneous catalyst for the synthesis of quinazolines using 2-bromobenzaldehydes (1 a) with benzylamines (2 b) and sodium azide in greener solvent ethylene glycol (EG) under ligand free condition. The prepared nanocomposites was examined using different characterization techniques such as X-ray diffraction (XRD), field emission gun-scanning electron microscopy (FEG-SEM), energy-dispersion X-ray (EDX), X-ray photoelectron spectroscopy (XPS), thermogravimetry (TGA) and Fourier-transform infrared spectroscopy (FT-IR). The Cu2O-Fe3O4 nanocatalyst could be recycled upto six time without any loss of in its catalytic activity.

The pyrolysis behavior of polyvinyl chloride (PVC) in the presence of commercially available oxides catalysts was investigated using thermogravimetry. The pyrolysis proceeded under a heating rate of 5°C/min in the temperature range of 200–650°C. The thermogravimetric properties in terms of reduction in maximum degradation temperature and percent conversion were studied. The silica gel mesoporous catalyst, with a greater pore size and surface area, was found to be the most active materials in terms of reduction in maximum degradation temperature and increase in percent conversion. The alumina acidic, silica ppt, and alumina neutral catalysts also showed good results; however, their effects were less pronounced as compared to silica gel. The effects of these different catalysts show that surface area, pore size, and number of acidic sites are found to be the major factors for the energy efficient degradation of polymers.