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Detailed investigation on the insulation and permeability characteristics of rigid polyurethane foam loaded with micron-sized Turkey feather powder depending on the free volume change
(SAGE Publiscations Ltd, 2023) Soykan, Uğur; Çetin, Sedat; Yahşi, Uğur
This study brokes new ground to understand the insulation and permeability performances of rigid polyurethane foams (RPUFs) containing the different contents of micron-sized turkey feather powders (TFPs) depending on the free volume change for the first time. The effects of TFPs loading on the RPUFs were investigated by the examination of their structural and chemical features (particle size and ATR-FTIR analyses), free volume property (PALS analysis), insulation features (thermal conductivity and sound absorption tests), permeability performance (air and water vapor permeability tests) and cellular topology (SEM). PALS analysis results revealed that the addition of TFPs into the foams led to the sharp decrease in all free volume parameters since TFPs caused the formation of the disordered cells by occupying the holes in the matrix. Furthermore, both thermal conductivity and acoustic performance of the resulting foams get worse when compared to unfilled RPUF. This results were attributed to the formation of thinner and weaker cells during polymerization, reduction in the amount of CO2 inside the cells, enhancement in the solid-phase level in the matrix due to the increasing of volumetric density. Additionally, the foam samples with high content of TFPs showed considerably lower air and water vapor permeabilities when compared to neat RPUFs due to the dominant hydrophobic character of the keratin and reduction in the degree of vacancies in the matrix. SEM analysis also revealed that TFPs showed good compatibility with RPUF, but the distorted and irregular shaped cellular morphology was obtained at high contents.
Properties of the uniaxial and biaxial nematic phases of the dodecyltrimethylammonium bromide/1-dodecanol/water lyotropic mixture including azo dye and drug molecules
(Taylor & Francis Ltd, 2024) Akpınar, Erol; Tabak, Merve; Reis, Dennys; Neto, Antonio Martins Figueiredo
Lyotropic nematic phase properties of novel mixtures of dodecyltrimethylammonium bromide (DTMABr)/1-dodecanol (DDeOH)/water, doping with anionic azo dyes (amaranth and tartrazine) and a drug molecule disodium cromoglycate (cromolyn, DSCG), were investigated. The textures of the uniaxial and biaxial nematic phases were observed by polarizing optical microscopy (POM). Uniaxial-to-biaxial nematic phase transitions were determined from the temperature dependence of the birefringences via laser conoscopy. Partial phase diagrams of the mixtures were constructed as a function of concentrations of dyes and drug molecules by combining the POM and laser conoscopy results. Small-angle X-ray scattering (SAXS) was performed to evaluate micellar structure parameters. The results indicate that those dyes and drug molecules have a greater effect on (a) the nematic-nematic phase transition temperatures, (b) the biaxial-nematic phase-domain range in the partial phase diagrams, and (c) micelle-shape anisotropy, comparing to the addition of other conventional inorganic electrolyte ions. Furthermore, dye and drug molecules may be sequenced in the Hofmeister series of ions, considering the number of ionic groups in their molecular structures and also the chaotropic and/or kosmotropic degrees of the ionic groups. Since these molecules may have a resonance structure (e.g. DSCG), as a result of the existence of the aromatic parts in their structures, this resonance structure should be considered to investigate their effects on the stabilization of the lyotropic nematic phases.
Comparative de novo transcriptome analysis and random UV mutagenesis: Application in high biomass and astaxanthin production enhancement for Haematococcus pluvialis
(Springer, 2023) Telli, Murat; Ünlü, Ercan Selçuk
BackgroundAstaxanthin is a natural carotenoid with strong antioxidant capacity. The high demand on astaxanthin by cosmetic, food, pharmaceutical and aquaculture industries promote its value in the biotechnological research. Haematococcus pluvialis Flotow 1844 has been characterized as one of the most promising species for natural astaxanthin biosynthesis. Even though H. pluvialis as an advantage in producing astaxanthin, its slow grow-yield limits usage of the species for large-scale production.Methods and ResultsIn this study we generated mutated H. pluvialis strain by using one-step random UV mutagenesis approach for higher biomass production in the green flagellated period and in turn higher astaxanthin accumulation in red stage per unit algae harvest. Isolated mutant strains were tested for the astaxanthin accumulation and yield of biomass. Among tested strains only mutant strain designated as only MT-3-7-2 showed a consistent and higher growth pattern, the rest had shown a fluctuated and then decreased growth rate than wild type. To demonstrate the phenotypical changes in MT-3-7-2 is associated with transcriptome, we carried out comparative analysis of transcriptome profiles between MT-3-7-2 and the wild type strains. De novo assembly was carried out to obtain the transcripts. Differential expression levels for the transcripts were evaluated by functional annotation analysis.ConclusionsData showed that increased biomass for the MT-3-7-2 strain was different from wild type with expression of transcripts upregulated in carbohydrate metabolism and downregulated in lipid metabolisms. Our data suggests a switching mechanism is enrolled between carbohydrate and lipid metabolism to regulate cell proliferation and stress responses.
Chemical composition and source apportionment of PM2.5 at a suburban site in the northwestern part of Turkey
(Vinca Inst Nuclear Sci, 2023) Karadeniz, Hatice; Sağırlı, Eda; Karakaş, Serpil Yenisoy
In this study, daily fine particulate matters (PM2.5) were sampled between Febru-ary 22, 2011 and February 22, 2012 in Bolu Abant Izzet Baysal University Cam-pus. 277 PM2.5 samples were collected by using a stacked filter unit. The 51 ele-ments (Li, Be, Na, K, Mg, Al, P, S, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ge, As, Se, Rb, Sr, Y, Mo, Cd, Sn, Sb, Cs, La, Ce, Pr, Nd, Eu, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Hf, W, Pt, Au, Pb, Bi, Tl, Th, U) were determined using ICP-MS technique. The most frequently observed elements were Ti, V, Cr, Mn, Fe, Ce, and Cd in PM2.5. Aluminum, Ca, Na, Fe, K, and Mg were the elements having the largest arithmetic means. The concentrations of elements in the summer seasons were higher than the concentrations of elements in the winter season except for As and Bi. Source apportionment of elements was performed by using positive matrix factorization. Five sources were determined for the samples namely sea salt (Na, K, Mg, Ca), coal combustion (As, Pb, Bi, Tl, Cd, Sb, Se, Mo), wood and coal combustion (K, Rb, Se, Cs, Sb, Pb, Bi, Tl, Fe, Mn, Cd), soil (Ca, Mg, Ti, Fe, Y, La, Ce, Pr, Nd, Sm, Gd, Th), and industrial activity - iron-steel works (Cr, Mo, Fe, Ni, Cu, Mn, Cd, Sb, Ca). The factor of wood and coal combustion showed the same trend in the region for the whole year.
Meta-analysis of sugar beet (Beta vulgaris L.) transcriptome profiles under different biotic and abiotic stress conditions
(Springer, 2023) Bulut, Burak; Gürel, Songül; Ünüvar, Ömer Can; Gürel, Ekrem; Ünlü, Ercan Selçuk
Sugar beet (Beta vulgaris L.) meets the 21% of world sugar production. Soil pollution, biotic and abiotic factors in production areas greatly reduce product quantity and quality. Sugar beet responds to biotic and abiotic stresses such as drought, salt, heat, light, and infections of nematode, bacteria and fungi at the molecular level. Understanding molecular mechanisms require comprehensive genomics studies in order to control these mechanisms to increase the yield and quality. Transcriptome studies performed under stress conditions can shed light on the responses of plants at the molecular level. In addition, meta-analysis can help to find common responses under different stress conditions. In this study four different stress-related transcriptome data were used: two of them are related with biotic stress (nematode and fungi infection) and two of them are related with abiotic stress (ABA treatment and salt stress). In this study, we performed meta-analysis of studies conducted under biotic and abiotic stress conditions. Our results revealed 460 commonly regulated genes from biotic stress related data and 1031 commonly regulated genes from abiotic stress related data. Our data also showed that expression of ten genes is controlled regardless of the type of stress condition. The data can be useful for understanding the molecular aspect of adaptive stress response in sugar beet.
Microwave-mediated approach to highly substituted nitropyrimidines via double Mannich reactions and their biological propertie
(Pergamon-Elsevier Science Ltd, 2022) Yıldırım, Muhammet; Yıldırım, Arzu; Gülbenek, Cansu
In the current study, new polysubstituted nitropyridimines were efficiently synthesized via double Mannich cyclizations of diaryl substituted b-nitroenamines with formaldehyde and aniline derivatives under microwave irradiation for 30-40 min. Furthermore, an antioxidant study showed that some of the nitropyridimines have moderate to low scavenging activity against DPPH radical. Also, in a preliminary antibacterial activity test of selected products, only one product exhibited moderate antibacterial effect against S.Epidermidis bacteria. (c) 2022 Elsevier Ltd. All rights reserved.
H2(g) production from dimethylamine borane by Cu0/WO3 NPs catalyst
(Scientific and Technological Research Council Turkey, 2023) Al-Hameedaw, Doaa; Karaboğa, Seda; Morkan, İzzet
Cu0 NPs supported on tungsten (VI) oxide (WO3) were in situ generated from the reduction of Cu2+ ions during dehydrogenation of dimethylamine borane (DMAB). The Cu0/WO3 NPs displayed tangible catalytic activity in H2 (g) releasing reaction and they were identified by using advanced techniques. Cu0/WO3 NPs were found as active catalyst providing one equiv. H2(g) per mole of DMAB. The results from TEM images display the formation of Cu0 NPs with an average particle size of 4.6 ± 1.0 nm on the surface of WO3. Moreover, Cu0/WO3 NPs with various metal loadings were prepared and tested as catalyst in dehydrogenation reaction to find the optimum metal loading on WO3 support. The highest H2 generation rate was achieved for 4.0% wt. Cu0/WO3 catalyst with TOF value of 39 h?1 in the reaction conditions. Additionally, effect of various catalyst concentration and temperature is discussed on the reaction kinetics for reaction catalyzed by Cu0/WO3 NPs.
Design, synthesis and human carbonic anhydrase I, II, IX and XII inhibitory properties of 1,3-thiazole sulfonamides
(Pergamon-Elsevier Science Ltd, 2022) Erigür, Esra Caner; Altuğ, Cevher; Angeli, Andrea; Supuran, Claudiu T.
Carbonic anhydrases (CAs, EC 4.2.1.1) are categorized as metalloenzymes and are widespread in both eukaryotes and prokaryotes. In mammals, 16 different isoforms of carbonic anhydrase were isolated and categorized as catalytic human isoform; cytosolic CAs (CA-I, II, III, VII and XIII), membrane-associated CAs (CA-IV, IX, XII, XIV and XV), mitochondrial CAs (CA-VA and VB), secreted CAs (CA-VI) and non- catalytic human isoform; inactive CA-related proteins (CA-VIII, X, and XI).1,2 Carbonic anhydrases, which are included in the enzyme family, help to the reversible conversion of carbon dioxide and water to bicarbonate anion and proton presence of Zn2+ ion at the catalytic site. They also provide transportation of carbon dioxide (CO2), keeps acid-base balance, regulation of pH, etc.3,4 By means of their critical participation in many regulatory physiologic processes, they play an active role in the treatment of many diseases such as glaucoma, epilepsy, obesity edema, cancer, neuropathic pain, etc.5
Quercetin- and caffeic acid-functionalized chitosan-capped colloidal silver nanoparticles: One-pot synthesis, characterization, and anticancer and antibacterial activities
(Beilstein-Institut, 2023) Kurt, Akif Hakan; Olutaş, Elif Berna; Avcıoğlu, Fatma; Karakuş, Hamza; Sungur, Mehmet Ali; Öztabağ, Cansu Kara; Yıldırım, Muhammet
The presented study comprises the one-pot synthesis and the characterization of quercetin-and caffeic acid-functionalized chitosan-capped colloidal silver nanoparticles (Ch/Q-and Ch/CA-Ag NPs), and their antibacterial and anticancer activities. The formation of Ch/Q-and Ch/CA-Ag NPs has been confirmed by ultraviolet-visible (UV-vis) spectroscopy, Fourier-transform infrared (FTIR) spectroscopy, and transmission electron microscopy (TEM). The characteristic surface plasmon resonance (SPR) absorption band has been found at 417 and 424 nm for Ch/Q-and Ch/CA-Ag NPs, respectively. The formation of a chitosan shell comprising quercetin and caffeic acid, which surround the colloidal core Ag NPs, was confirmed by UV-vis, and FTIR analyses, and moni-tored by TEM microscopy. The size of nanoparticles has been determined as 11.2 and 10.3 nm for Ch/Q-and Ch/CA-Ag, respec-tively. The anticancer activity of Ch/Q-and Ch/CA-Ag NPs has been evaluated against U-118 MG (human glioblastoma) and ARPE-19 (human retinal pigment epithelium) cells. Both NPs showed anticancer activity, but Ch/Q-Ag NPs seemed to be more effective on cancer cell lines (U-118 MG) in comparison to healthy ones (ARPE-19). Furthermore, the antibacterial activity of Ch/Q-and Ch/CA-Ag NPs against Gram-negative (P. aeruginosa and E. coli) and Gram-positive (S. aureus and S. epidermidis) bacteria was determined, and dose-dependent antibacterial effects were found.
Current-voltage characteristics of nano whisker ZnO/Si heterojunction under UV exposition
(Elsevier Science Sa, 2022) Koç, Nevin Soylu; Altıntaş, Sevgi Polat; Gökçen, Muharrem; Doğruer, Musa; Altuğ, Cevher; Varilci, Ahmet
In/ZnO/p-Si heterojunction diode was produced to investigate the photo-responsivity and electrical features under ultraviolet (UV) light. A hydrothermal synthesis technique was used to coat the ZnO layer on the p-Si single crystal as nanowhisker/rods. The formation of surface and nanowhisker properties of the ZnO layer were investigated by scanning electron microscope (SEM). The I-V (current-voltage) analysis of the In/ZnO/p-Si diode was realized in dark and under UV (290-400 nm) illumination. Further, the main electrical parameters of the diode; such as reverse bias saturation current (I-V), ideality factor (n), zero bias barrier height (Phi(Bo)), resistance (R) and interface state density (N-ss) were obtained from the experimental I-V measurements by thermionic emission (TE) and Card and Rhoderick's function. Also, the power law of the photocurrents (I-PC), photoresponsivity (PR) and response time were extracted. Photo-responsivity and response time values of In/ZnO/p-Si heterojunction diode were obtained as 2.0 A/W and (rise/decay) 160/200 ms, respectively.
The effects of Ni/Cu co-doped ZnO nanorods: Structural and optoelectronic study
(Springer, 2022) Şenol, Sevim Demirözü; Arda, Lütfi
The hydrothermal method was used to synthesize Zn0.99-xNixCu0.01O (x = 0.00 to 0.05 with a 0.01 increment) nanorods. The X-ray diffraction method was used to provide the structural analysis. It was observed that all Ni/Cu co-doped ZnO nanorods are single phases. The Scanning Electron Microscope and Electron Dispersive Spectroscopy were employed to monitor the surface morphology, shapes, size, and elemental compositions of the Ni/Cu co-doped ZnO nanorods. The Fourier Transform Infrared studies were performed and detailed. The UV-Spectrophotometer was used to obtain the optical properties of the nanorods. The energy band gaps of Ni/Cu-doped ZnO nanorods were calculated and their effects on optical properties were discussed. Five different models were used to calculate the refractive index. Multi-doped (Ni and Cu) ZnO nanorods were successfully produced using the hydrothermal method and their structural, band gap and refractive indexes were discussed for optoelectronic and sensor applications.
Evaluation of crystallinity, thermal, mechanical and morphological features of high density polyethylene composites reinforced with crosslinked semifluorinated acrylate polymer microspheres
(SAGE Publications Ltd, 2023) Soykan, Uğur; Çetin, Sedat
This study mainly aims both to prepare well-shaped crosslinked 3,3,4,4,5,5,6,6,7,7,8,8,8 tridecafluorooctyl-4-(acrloyloxy) benzoate (ABCF13) polymer microspheres and to investigate the influences of the prepared microspheres addition on the crystallinity, thermal, mechanical and morphological features of high density polyethylene (HDPE). The suspension polymerization method was used for the production of well-defined microspheres and, the content of the microspheres varied from 1.0% to 10.0% in the composites. The characterization of crosslinked poly(ABCF13) microsphere-loaded HDPE composites were performed via powder X-ray diffraction, differential scanning calorimeter, universal mechanical (tensile and impact) testers and scanning electron microscope (SEM) techniques. According to the experimental findings, a and b unit cell parameters increased initially and reached maxima with the sample including 5.0% microsphere, which were followed by dramatic decreases, while c parameter remained relatively unchanged. Thermal analysis also showed that the melting temperature of HDPE reduced with the initial loading of the microspheres, then stayed at a plateau value of about 129 degrees C due to the formation of lattice distortions, generation of microstructural disorders and the defects in the crystal structures. The mechanical test results revealed that there existed considerable improvements in tensile strength, modulus and impact strength. The maximum tensile strength 25.66 MPa, elastic modulus 499.30 MPa and maximum absorbed energy in the impact test 26.84 kJ/m(2) (29%, 42% and 41% improvement, respectively) were achieved with the blend involving 5.0% microsphere. After the maxima, the mechanical characters depicted weakening trend as the microsphere content increased in the matrix. The SEM analyses revealed that although there existed fibrillar formations in all samples, the extensions decreased with the increase of the microsphere content. While ductile behavior was observed with the formation of long-bulky extensions at low contents, brittleness started to prevail at high contents with some short and thin fibrils.
Synthesis and organogelation properties of bis-carbamate compounds bearing spacers with a stereogenic center
(Springer, 2023) Ordu, Öznur Demir
A series of bis-carbamates with a stereogenic center were prepared as low-molecular-weight organic gelators. The gelating propensity of racemates and pure enantiomers was examined in a range of organic solvents to explore the effects of chirality and the para-alkyl chain length on self-assembly. It was found that the gelation abilities in vegetable oils and esters were mainly affected by the para-alkyl chain length and the number of carbons in the spacer between the carbamate groups. In addition, molecular chirality was found to have a significant effect on the gelation properties of bis-carbamate derivatives with three-carbon spacer. Furthermore, morphology of the bis-carbamate gels was investigated by optical microscopy and scanning electron microscopy. Birefringent helix-like structures between birefringent spherulites were observed by polarized optical microscopy in the gel structures of chiral bis-carbamate derivatives with three-carbon spacer. The bulk properties of the gels were evaluated through rheological studies. The results can be used for developing novel chiral gels and relevant applications such as enantiomeric separation. [GRAPHICS] .
Novel benzodioxatriaza and dibenzodioxadiazacrown compounds carrying 1,2,4-oxadiazole moiety
(De Gruyter Poland Sp. z o.o., 2022) Özer, Besra; Dürüst, Yaşar
A series of benzo (dibenzo)dioxadiaza and triazamacrocyclic ether compounds carrying 1,2,4-oxadiazole group has been successfully synthesized through N-substitution with 3-p-phenylsubstituted-5-chloromethyl-1,2,4-oxadiazoles. The structures of all the novel macrocycles were confirmed by spectral/physical data including HRMS measurements.
Alkyl chain length and headgroup dependent stability and agglomeration properties of surfactant-assisted colloidal selenium nanoparticles
(Elseiver, 2023) Olutaş, Elif Berna
In this study, we have systematically investigated and reported the growth, stability, and aggregation properties of selenium nanoparticles (Se NPs) in the presence of surfactant systems comprising different head groups and alkyl chain lengths. Here, the n-alkyl sulfates (C10-C14) and n-alkyl trimethylammonium bromides (C12-C18) were used as the anionic and cationic surfactants. The obtained results showed that the shortening in the alkyl chain length both in anionic and cationic groups does not affect the Se NPs morphologically, however it leads to a gradual increase in their mean sizes. It was also found that the surfactants having a cationic head group pave the way for forming the bigger NPs compared to the anionic ones. In addition, especially in the cationic group, the NPs were found to be in an increasing aggregation tendency with decreasing number of carbon atoms in the chain length. On the other hand, it was observed that the absorbance tends to decrease with time both in the anionic and cationic systems. The rate of decrease in the absorbance within the time revealed that the elongation in the alkyl chain length gives rise to a more stable nanoparticle solution for both surfactant systems. Further-more, the results revealed that the surfactants having an anionic head group kept the Se NPs more stable in their solutions as compared to cationic ones. The scanning electron microscopy images corresponding to absorption measurements taken for certain days suggested that the formation of aggregated structures, which increase along with time in the nanoparticle solution, is responsible for the accelerated decrease in the absorbance as the tail length decreases.
Self-assembly, surface, antibacterial, and solubilization properties of phenylglycine type amino acid-based cationic surfactants
(Elseiver, 2022) Olutaş, Elif Berna; Kartal, Necla Büşra; Yıldırım, Arzu Birinci
Here, synthesis and characterization of amino acid-based chiral cationic surfactants containing phenyl-glycine moiety, L-phenylglycine hydrochloride octyl ester (L-PgC8E), and L-phenylglycine hydrochloride decyl ester (L-PgC10E), and their physicochemical properties such as the micellization, surface, and volu-metric parameters have been reported. In addition, the structural analyses of the aggregates of these esters were also performed by dynamic light scattering (DLS) and transmission electron microscopy (TEM) techniques. It was found that the presence of a phenyl ring in the head group promoted the micelle formation leading to a smaller critical micelle concentration (CMC) value and enhancing the adsorption efficiency with an increased hydrocarbon chain. Besides, the antibacterial activities of the synthesized surfactants have been explored against three Gram-positive (G+) and seven Gram-negative (G-) bacteria below and above their CMC values by measuring the zone of inhibition diameter. The results showed that L-PgC8E was more active than L-PgC10E against all bacteria; this was explained by the formation of smal-ler and less stable aggregates that could interact efficiently with the bacterial membrane. Furthermore, the solubilization power (SP) of both surfactants for Methyl Red (MR) was determined, and it was found that L-PgC10E with a longer hydrocarbon chain and forming a large hydrophobic area by its large aggre-gates showed a more efficient solubilizing power.(c) 2022 Elsevier B.V. All rights reserved.
De novo assembly and annotation of microalga tetradesmus obliquus transcriptome
(Central Fisheries Research Institute, 2022) Ünüvar, Ömer Can; Ünlü, Ercan Selçuk
Tetradesmus obliquus is a unicellular green microalga and considered as a potential source for biotechnological production of pigments such as lutein. No genome-related data is available for T. obliquus that would increase the ability to develop new approaches in biotechnological applications. We present the first transcriptome data for T. obliquus. The aim of this study is to provide a comprehensive transcriptome annotation and identification of conserved genes involved in lutein pigment biosynthesis in Tetradesmus obliquus cells by analyzing pooled RNA-Seq data. Next-Generation Sequencing was applied for the pooled cDNAs library prepared by combining the cell cultures collected from samples exposed to dark and high light intensity conditions. Transcripts were assembled by the de novo assembly approach. Trinotate software was used for functional annotation of assembled transcripts. We also carried out BLAST analysis comparing the transcriptome data against known lutein biosynthesis genes. The 49.15% of the assembled sequences were functionally annotated, providing a total of 21490 unigenes. Our data also revealed the transcript sequences for ten conserved genes required for lutein biosynthesis. The data produced in this study can be used for molecular approaches in biotechnological applications related to T. obliquus, such as increasing the yield of pigment production.
A new interpretation of the optical interference figures observed in a lyotropic biaxial nematic phase for a ternary mixture of DTMABr, 1-DDeOH and H2O
(ELSEVIER, 2022) Lüders, D. D.; Akpınar, Erol; Kimura, Newller M.
The lyotropic ternary mixture of dodecyltrimethylammonium bromide (DTMABr), 1-dodecanol (DDeOH) and water (H2O) was studied by optical conoscopy and Abbe refractometer techniques. The present mixture showed a large biaxial phase domain (N-B) located between two different uniaxial ones in the partial phase diagram, one optically positive (N-D) and the other negative (N-C). The N-B phase exhibits two optic signs as a function of the temperature, each of which was equal to the neighboring uniaxial phases. The temperature dependence of the refractive indices was measured along the N-C - N-B - N-D phase transitions. In addition, we are reporting for the first time a new interpretation of the optical interference figures observed along the N-B phase.
Investigation of the relation between free volume and physico-mechanical performance in rigid polyurethane foam containing turkey feather fibers: Part 2
(SAGE PUBLICATIONS LTD, 2022) Soykan, Uğur; Khaleel, Mustafa; Çetin, Sedat; Yahşi, Uğur; Tav, Cumali
Rigid polyurethane foams (RPUFs) were modified with 0-15 wt.% turkey feather fibers (TFFs) produced from waste turkey feathers. One-shut free rising method was used for the production of TFFs-filled-RPUFs in a closed mold. The dependence of mechanical performance and water vapor permeability (WVP) feature of the final foams on TFFs loading was evaluated with free volume change. The free volume analysis was performed via Positron Annihilation Lifetime Spectroscopy (PALS), while the mechanical and WVP characteristics were determined with the use of the universal tester machines. PALS findings showed that the incorporation of TFFs with RPUF matrix caused the considerable diminishment in the free volume due to TFFs serving as a filling material and formation of strong secondary bonds between components. Moreover, tensile strength and extension of the foams decreased with the increasing of TFFs, which caused by the occurrence of noteworthy restriction on the spatial alignment and orientation capability of polyurethane chains due to the lack of sufficient free volume allowing the chains to move freely. As for the compression tests, all the TFFsloaded RPUFs depicted substantially lower performance due to TFFs interfering with the ordered organization of isocyanate domains. Moreover, impact test results showed that the addition of TFFs into RPUF matrix brought about the insufficient impact energy delocalization throughout the matrix due to the restriction on the mobility of polymer chains. Additionally,the remarkable diminishment in WVP was recorded due to the reduction in the number of vacancies and constitution of keratin composed of roundly 60% of hydrophilic protein (especially cystine). All in all, this study established a strong links between free volume and characteristics of TFFs-loaded RPUFs.
Preparation of 4-arylthiazol-2(3H)-ones and the three-component synthesis of Multidentate 5,5 '-methylenebis[4-arylthiazol-2(3H)one] ligands
(Georg Thieme Verlag KG, 2023) Ortuno, Juan F.; Poyraz, Samet; Belabbes, Asmaa; Kavas, Özge; Belveren, Samet; Altuğ, Cevher
The synthesis of 4-arylthiazol-2(3H)-ones is reported employing a novel and mild methodology using benign solvents. In a second objective, the multicomponent preparation of 5,5'-methylenebis[4-arylthiazol-2(3H)-ones] is described following the same strategy. The analysis of the mechanism is also studied and confirmed using chemical tests.

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