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With the reduction of technology nodes to less than 10 nm, ruthenium (Ru) has emerged as a viable replacement for copper (Cu) for back-end-of-the-line (BEOL) interconnects. Good surface uniformity while maintaining an appropriate thickness of Ru is required during the fabrication process, which can be achieved by employing the chemical mechanical planarization (CMP) process. However, a crucial step in the CMP process is to attain reasonable removal rates of high-mechanical-strength and chemically inert metals such as Ru. Hence, this study investigates a competent CMP slurry comprising potassium iodate (KIO3) as an oxidizer and fumed silica as an abrasive for polishing Ru. The polishing results show that adding KIO3 to fumed silica modifies the silica particles, thereby enhancing the removal rates of the metal. thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR) and ultraviolet-visible spectroscopy (UV-Vis) characterization confirm the modification of the silica particles by KIO3 as an oxidizer. The studies reveal that the abrasive concentration usage was reduced to 60% due to silica modification. The surface morphology of the treated metal surface was evaluated using field emission scanning electron microscopy (FESEM). No adsorbed contamination or pitting is observed on the metal surface. The inhibition effect of 1,2,3-benzotriazole (BTA) was investigated in detail by performing potentiodynamic polarization experiments. The nature of the metal dissolution in KIO3 was investigated by examining the effect of solution temperature on the etch rates. The thermodynamic process of the system was found to be endothermic in nature, and the dissolution followed an associative mechanism. The results reported in this paper reveal that the proposed slurry can be used to significantly improve Ru polishing efficiency and provide desired selectivity without compromising the surface quality of the metal. [ABSTRACT FROM AUTHOR]

In this study, nylon 66 industrial fabrics (used in the conveyor belts) were exposed artificially to the accelerated ultraviolet rays and the degradation mechanism was evaluated using spectral, thermal, and morphological analyses. The fabric samples were exposed to six different exposure times in a UV chamber and tensile tests were carried out in the main and bias (45°) directions. The results showed that the shear modulus was reduced in the early stages covering 4 h of the UV radiation because of the linkages breakage and the increase in the amorphous regions. However, after this early stage, the shear modulus started to increase. The Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM) analysis, and X-ray photoelectron spectroscopy (XPS) study were also performed to evaluate the surface morphology and the degradation mechanism of the nylon 66 fibers after UV illumination. The results also revealed that the formation of new links by free radicals caused the change in the bond wavelengths. Furthermore, it was found that there was an interesting mechanism for the UV degradation of nylon 66 fabrics at different exposure times, as confirmed by the results obtained regarding the mechanical properties of the samples. The results of this study can be, therefore, helpful for the industrial application of nylon 66 woven conveyor belts exposed to solar UV radiation. [ABSTRACT FROM AUTHOR]

Saharan aloe vera cactus leaves fibers (SACLFs) are a biodegradable and renewable agro textile fiber enriched with cellulose polysaccharides. The isolation of cellulose nanocrystals (CNCs) from SACLFs is an alternative approach to reinforcement for bio-composites applications. In this study, we show that standard chemical methods for the extraction of cellulose microfibrils and sulfuric acid hydrolysis (64 wt%) will result in usable CNCs. The resulting CNCs were characterized by XRD, FTIR, TGA and TEM. Fourier Transform Infrared Spectroscopy (FT-IR) confirms that the maximum amount of noncellulosic materials is removed from SACLFs. High yield content (32%) of CNCs is achieved by sulfuric acid hydrolysis and sonication process. It also enhances the crystalline size and crystallinity index of CNCs, which are confirmed by XRD. TEM analysis of CNCs shows a rod-like structure with diameter (10–14 nm), length (200–255 nm) and high aspect ratio of 18–20, which confers good reinforcing properties. These were tested in biodegradable agar film, whose tensile strength is increased by 27% when 5 wt% of CNCs from SACLFs was incorporated into the matrix. The SACLFs represent an interesting source of cellulosic reinforcing materials. [ABSTRACT FROM AUTHOR]

This work presents the preparation and characterization of hybrid organic-inorganic optically active poly(amide-imide)/nano-Fe3O4 composites with different amount of modified Fe3O4 nanoparticles as new nanocomposites by ultrasonic irradiation and characterized by Fourier transform infrared spectra, X-ray diffraction, scanning electron microscopy (SEM), thermogravimetric analysis and vibrating sample magnetometry. The surface of Fe3O4 nanoparticles was modified with 3-aminopropyltriethoxyl silane because of the homogeneous distribution of nano-Fe3O4 in polymer matrix, which the SEM results confirmed that the Fe3O4 nanoparticles were dispersed uniformly in polymer matrix. Furthermore, as compared with pure polymer, thermogravimetric analysis data indicated an improvement of thermal stability of nanocomposites. [ABSTRACT FROM AUTHOR]

Thermal Analysis determines a set of methods for the study of the selected physical properties of the substance under the influence of temperature or atmosphere. Thermogravimetric (TG) analysis is very useful for studying the kinetics of gasification processes. However, by itself TG does not allow the direct identification of the gases released from the sample during the thermal treatment. For this purpose, coupling TG to a spectroscopic interrogation method, such as Fourier-Transform-Infrared (FT-IR) spectroscopy, is an excellent solution. The objective of this paper is to ascertain the usefulness and limitations of TG-FTIR technique in the study of biomass gasification and to determine gasification product evolution patterns and yields for heavy metal contaminated (HMC) samples of Miscanthu s x giganteus , Sida hermaphrodita , Spartina pectinata and Panicum virgatum . In experiments reported in this paper, biomass samples were heated at 10° C min −1 in a nitrogen environment and the volatile products were swept immediately into a cooler gas cell, which minimized secondary reactions. Process products were quantitatively analysed by gas-phase Fourier transform infrared (FT-IR) spectroscopy. This gas analysis combined with weight loss measurements of the heated material ensured generally good mass-balance closure. The paper discusses the techniques employed to identify the evolved products and presents the product evolution patterns and yields. [ABSTRACT FROM AUTHOR]

The present research work aimed to characterize new natural cellulosic kusha fibers extracted from the kusha grass plants. The physical and chemical properties of kusha fibers such as cellulose content (70.58%), lignin (14.35%), wax content (1.52%), ash content (2.46%), moisture content (8.01%), and density (1.1025 g cc−1) were identified. An X-ray diffraction of kusha fibers confirms the presence of cellulose with a crystalline index of 55.4%. Fourier transform infrared spectroscopy analysis was carried out to establish the certainty of using them as reinforcement fiber. Thermogravimetric analysis ensures thermal stability up to 357°C which is within the polymerization process temperature. [ABSTRACT FROM PUBLISHER]

PVC-based nickel tungstate is a newly synthesized composite material that has been used to make mechanically and thermally well-stable membrane. The composite material was qualitatively synthesized by the sol–gel method of material preparation. The composite material and prepared membrane have been selected and characterized on the basis of their chemical composition, ion-exchange capacity, and FTIR, TGA, and SEM analysis. It has verified the material nature, functional groups, thermal stability plus the phase transition, surface structure, porosity, ion transportation, etc. For the measurement of ionic potential, KCl, NaCl, and LiCl strong electrolytes are used, which helps to obtain the charge density of the membrane that decided the nature of membrane performance accordingly. Teorell–Meyer–Sievers theoretical approach is used to obtain the important parameters of examined membrane that included the transport number, mobility ratio, charge effectiveness, etc. [ABSTRACT FROM PUBLISHER]

Properties such as absorption, structural and external aspect of Carbopol/silver nanoparticles composites, prepared in DMF by heating process up to 30, 60, 80, 100 and 120 °C, were investigated by UV-visible, FTIR and SEM-EDS analyses. Samples were named respectively D30 to D120, according to the temperature at which they were extracted. The results showed that instead of the appearance of silver aggregates observed by SEM microscopy, all the obtained materials present a single absorption band centred at 430 nm, attributed to the classical surface plasmon excitation of the silver nanoparticles. The presence of silver nanoparticles is also proved by the X-ray powder diffraction XRD patterns, which show the appearance of small peaks corresponding to the face centered cubic (f.c.c.) silver phase in the case of D100 and D120 samples. Additionally strong interactions between silver ions and carboxylic groups of Carbopol were identified by ATR-FTIR spectroscopy. The thermal properties of the carbopol are effectively enhanced by the presence of silver nanoparticles as evidenced by thermo-gravimetric analysis. Furthermore the water loss that generally occurs at 100 °C in acrylic acid polymer was completely avoided in these new materials since less than 2 % of weight loss is recorded up to 160 °C. Finally, the inhibiting activity of Carbopol/silver nanoparticles composites against staphylococcus Aureus micro-organisms was confirmed for all the obtained materials, suggesting their suitable uses as effective growth inhibitors of micro-organisms and making them appropriate for diverse antimicrobial control systems. [ABSTRACT FROM AUTHOR]

Highlights: [•] TGA/FTIR has been applied to the pyrolysis of tobacco, glycerol and mixtures thereof. [•] The qualitative composition of the gases evolved in the main pyrolysis steps has been obtained. [•] The effect of glycerol in the qualitative composition of the gases evolved has been suggested. [Copyright &y& Elsevier]

In this study, cobalt-based metal-organic framework (MOF) powder was prepared via the solvothermal method using 2,6-naphthalenedicarboxylic acid (NDC) as the organic linker and N,N-dimethylformamide (DMF) as the solvent. The thermal decomposition of the pristine cobalt-based MOF sample (CN-R) was identified using a thermogravimetric examination (TGA). The morphology and structure of the MOFs were modified during the pyrolysis process at three different temperatures: 300, 400, and 500 °C, which labeled as CN-300, CN-400, and CN-500, respectively. The results were evidenced via field-emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD). The crystallite size of all samples was calculated using Scherrer's equation. The smallest crystallite size of 7.77 nm was calculated for the CN-300 sample. Fourier transform infrared spectroscopy (FTIR) spectra were acquired for all the samples. The graphical study of the cyclic voltammogram (CV) gave the reduction and oxidation peaks. The charge transfer resistance and ionic conductivity were studied using electrical impedance spectroscopy (EIS). The galvanostatic charge–discharge (GCD) responses of all samples were analyzed. The relatively high specific capacitance of 229 F g−1 at 0.5 A g−1 was achieved in the sample CN-300, whereby 110% of capacitance was retained after 5000 cycles. These findings highlighted the durability of the electrode materials at high current densities over a long cycle. [ABSTRACT FROM AUTHOR]

• It was studied and presented the zinc doped molybdenum oxide with different weight percentage (2%, 3.3%, 4% and 5%), it was denoted that the zinc doping percentage influence: • The crystallographic structure by using the X-ray diffraction technique. • The optical properties by using the Fourier transform infrared spectroscopy and the UV–vis diffuse reflectance spectra analysis. • Photocatalytic activity by measuring its effect on the methylene blue (MB). In this study, we report a synthesis of nanobelts-form zinc (Zn) doped molybdenum oxide (MoO 3) with different weight percentages (2%, 3.3%, 4%, and 5%). The synthesized nanobelts grain size is of 45 nm. The preparation process and characterization techniques are presented in detail. Structural properties are studied by using the X-ray diffraction technique, scanning electron microscopy and transmission electron microscopy. The optical properties are investigated by using the Fourier transform infrared spectroscopy, UV–Vis reflectance spectra analysis, Raman spectroscopy, and fluorescence techniques. It was founded that Zn doping concentration highly influences the crystallographic structure where it passes from the insertion to the substitution alloys. The band gap decreases from 2.96 eV to 2.83 eV. The good structural and optical properties were obtained for the 5%Zn. The photocatalytic effect of the materials was studied for the pure and 5%Zn doped MoO 3 and it was denoted that Zn doping influences it highly. [ABSTRACT FROM AUTHOR]