IR SPECTRAL STUDY ON THE NATURE OF 2-PYRIDINE ALDOXIME METHYL CHLORIDE INTERACTION WITH SOME STEROLS. I. CHOLESTEROL

abstract: The aim of this spectral study was to investigate the character of the molecular interaction of cholesterol (Ch) with 2-pyridine aldoxime methyl chloride (2-PAM). For this purpose it was made a comparative analysis of the FTIR and conventional IR spectra carried for Ch, 2-PAM and the remnant obtained after solvent (CHCl3) removal from an equimolecular mixture of 2-PAM:Ch. The analyses of the spectra, obtained using KBr pellets technique, indicates that the investigated molecular interaction is hydrogen bonding mediated

Physical Chemical Investigation of Gamma-Irradiated Parchment for Preservation of Cultural Heritage

The historical artefacts of parchment are prone to degradation if the storage conditions are improper due to the collagen structure having a limited stability under physical, chemical, and biological agent attacks. The parchment structure is difficult to characterize due to the variety of manufacturing traditions (eastern/western), intrinsic variability of skins (i.e., species, breeding variation, living conditions, effects of pathologies, etc.), biodeterioration, and aging, and the main concern in its analysis is its uniformity. The deterioration of parchment collagen produces a rather stiff or in some circumstances, a relaxed structure. Any intervention or treatment of unique, very precious cultural heritage artefacts must not negatively influence the properties of the component materials. Gamma irradiation is a relatively new technique of bioremediation. Data on the leather properties pre- and post-ionizing radiation bioremediation treatments are few in the literature. Fewer data are available on the historical leather and parchment physical chemical characteristics after ionizing gamma irradiation. This research had two main objectives: (i) the characterization of the parchment structure’s uniformity across the analyzed areas and its mechanical properties, i.e., tensile stress by mechanical tests and ATR-FTIR spectroscopy; and (ii) to establish parchment tolerance when exposed to ionizing gamma radiation as a pre-requisite for cultural heritage preservation irradiation treatment. It was found that the mechanical tests and ATR-FTIR spectroscopy may identify changes in the parchment’s irradiated structure and that the preservation of cultural heritage parchment artefacts may be performed at maximum 15 kGy gamma irradiation dose

Maize Stalk Material for On-Site Treatment of Highly Polluted Leachate and Mine Wastewater

New research applications involving the use of cellulosic material derived from maize stalk for on-site treatment of leachate were evaluated for specific removal of Cu(II) and Fe(III) from real, highly polluted tailing pond and mine wastewater samples. Two major issues generated by anthropic mining activities were also tackled: wastewater metal content decrease to improve water quality and subsequently metal specific recovery, increasing the economic efficiency of metal production by using a green technology for residual management. Rapid saturation of the maize stalk mass determined in batch studies and the mine pilot experiment led to diminished metal concentrations in the second pilot experiment, where Cu(II) and Pb(II) from synthetic solutions were monitored in order to test biomaterial performances. In addition, in the second pilot experiment, maize stalk removed Pb(II) in the first 36 h, below the determination limit of the analytical method. The biomaterial bed in the column was saturated after 252 h of inflow solution. FTIR-ATR, TG and SEM techniques probed the interaction between maize stalk polar groups C=O, –OH, C–O and tailing water metallic ions by large FTIR band displacements, intensity decrease and shape changes, modification of thermal stability and by changes in the appearance of adsorbent microstructure images owing mainly to ion exchange mechanism

The Assesment of the Decayed Lime Wood Polymeric Components by TG and FT-IR Parameters Correlation

The restoration and conservation practices of wooden artifacts increasingly need more nondestructive, inexpensive and no-time consuming diagnosis methods. A number of twelve samples of lime wood in various states of degradation from furniture and panel painting were investigated by thermal analysis and infrared spectroscopy. The present work was undertaken to quantify the degree of complementarity of the TG and FT-IR methods by assessing >the ration between cellulose, hemicelluloses and lignin of the decayed lime wood by the correlation of the parameters RTG = ΔmHC /ΔmL from TGA data, and R1FTIR = Aab1370/Aab1505, R2FTIR = Abz1370/Abz1505, R3 FTIR = Iab1370/Iab1505, R4FTIR = Ibz1370/Ibz1505 , from the corresponding peaks of cellulose and hemicelluloses at ~ 1370 cm-1 and of lignin at 1505 cm-1 in FT-IR spectra, where RTG is the ratio between the mass loss of cellulose & hemicelluloses ΔmHC and the mass loss of lignin ΔmL; R1FTIR, R2FTIR, are the ratio between the absolute peaks area Aab1370/Aab1505, and the normalized peaks area Abz1370/Abz1505, respectively, while R3FTIR, R4FTIR are the ratio between the absolute peaks intensity Iab1370/Iab1505, and the normalized peaks intensity Ibz1370/Ibz1505, respectively. We found that the TG parameter decreases in the same order as FT-IR parameters R1 FTIR, R2FTIR, R3FTIR, R4FTIR, and relates well in the values with R1FTIR

Compatibility of Drotaverine Hydrochloride with Ibuprofen and Ketoprofen Nonsteroidal Anti-Inflammatory Drugs Mixtures

Formulations with two or more active pharmaceutical ingredients (APIs) are a researched trend due to their convenient use compared with multiple medications. Moreover, drug-drug combinations may have a synergistic effect. Drotaverine hydrochloride (D-HCl) is commonly used for its antispasmodic action. The combination of a spasmolytic and an analgesic drug such as ibuprofen (Ibu) or ketoprofen (Ket) could become the answer for the treatment of localized pain. D-HCl:Ibu and D-HCl:Ket drug-drug interactions leading to the formation of eutectic compositions with increased bioavailability, obtained by mechanosynthesis, a green, solvent-free method was explored for the first time. The compatibility of Ibuprofen, Ketoprofen, and Drotaverine Hydrochloride was investigated using differential scanning calorimetry (DSC), X-ray diffraction (XRD), and Fourier-Transform Infrared spectroscopy (FTIR). Solid-liquid equilibrium (SLE) phase diagrams for the binary systems of active pharmaceutical ingredients were developed and the Tammann diagrams were designed to determine the eutectic compositions. The excess thermodynamic functions GE for the pre-, post-, and eutectic compositions were obtained using the computed activity coefficients data. Results show that drotaverine-based pharmaceutical forms for pain treatment may be obtained at 0.9 respectively 0.8 molar fractions of ibuprofen and ketoprofen which is advantageous because the maximum allowed daily dose of Ibu is about 6 times higher than those of D-HCl and Ket. The obtained eutectics may be a viable option for the treatment of pain associated with cancer therapy

Investigation of the Effects of Rapid Thermal Annealing on the Electron Transport Mechanism in Nitrogen-Doped ZnO Thin Films Grown by RF Magnetron Sputtering

Nitrogen-doped ZnO (ZnO:N) thin films, deposited on Si(100) substrates by RF magnetron sputtering in a gas mixture of argon, oxygen, and nitrogen at different ratios followed by Rapid Thermal Annealing (RTA) at 400 °C and 550 °C, were studied in the present work. Raman and photoluminescence spectroscopic analyses showed that introduction of N into the ZnO matrix generated defects related to oxygen and zinc vacancies and interstitials. These defects were deep levels which contributed to the electron transport properties of the ZnO:N films, studied by analyzing the current–voltage characteristics of metal–insulator–semiconductor structures with ZnO:N films, measured at 298 and 77 K. At the appliedtechnological conditions of deposition and subsequent RTA at 400 °C n-type ZnO:N films were formed, while RTA at 550 °C transformed the n-ZnO:N films to p-ZnO:N ones. The charge transport in both types of ZnO:N films was carried out via deep levels in the ZnO energy gap. The density of the deep levels was in the order of 1019 cm−3. In the temperature range of 77–298 K, the electron transport mechanism in the ZnO:N films was predominantly intertrap tunneling, but thermally activated hopping also took place

Multifunctional Leather Surface Design by Using Carbon Nanotube-Based Composites

This paper deals with original research in smart leather surface design for the development of multifunctional properties by using multi-walled carbon nanotube (MWCNT)-based nanocomposites. The conductive properties were demonstrated for both sheepskin and bovine leather surfaces for 0.5% MWCNTs in finishing nanocompositions with prospects for new material design intended for flexible electronics or multifunctional leathers. The photocatalytic properties of bovine leather surface treated with 0.5% MWCNTs were shown against an olive oil stain after visible light exposure and were attributed to reactive oxygen species generation and supported by contact angle measurements in dynamic conditions. The volatile organic compounds’ decomposition and antibacterial tests confirmed the self-cleaning experimental conclusions. Ultraviolet protection factor had excellent values for leather surfaces treated with multi-walled carbon nanotube and the fastness resistance tests showed improved performance compared to control samples. Scanning electron microscopy with energy dispersive X-ray (SEM-EDX), X-ray photoelectron spectroscopy (XPS), and attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy analysis confirmed the influence of different leather surfaces on MWCNT dispersion with an effect on nanoparticle reactivity and efficiency in self-cleaning properties. Multifunctional leather surfaces were designed and demonstrated through MWCNT-based nanocomposite use under conventional finishing conditions

Outcomes and Economic Evaluation in Delayed Two-Stage Breast Reconstruction in Romania: The Influence of Radiotherapy

The current paper is a retrospective cohort study conducted on sixty-seven patients who underwent two-stage breast reconstruction over a 5-year period (2015–2020). Forty-one (61.2%) patients received radiotherapy (RT group), and twenty-six (38.8%) did not (non-RT group). Data regarding patients, oncological therapies, type of reconstruction, time of hospitalization, complications, and costs were collected. The statistical analysis was performed using IBM SPSS Statistics 25. General complications were noted for 18 patients (43.9%) in the RT group and for 7 patients (26.9%) in the non-RT group. Major complications were observed only in the first group (five patients–12.2%). The mean time of hospitalization in the RT group was 14.83 days for patients with complications versus 9.83 days for those without complications and 15.5 days versus 8.63 days, respectively, in the non-RT group. The mean cost for patients without complications was 235.64 euros, whereas the cost for patients with complications was 330.24 euros (p = 0.001). Radiation therapy can affect the overall outcome by increasing the risk of complications and increasing costs; however, our paper shows that the association of alloplastic reconstruction in patients with radiotherapy can be performed safely and with low costs in carefully selected patients

Outcomes and Economic Evaluation in Delayed Two-Stage Breast Reconstruction in Romania: The Influence of Radiotherapy

The current paper is a retrospective cohort study conducted on sixty-seven patients who underwent two-stage breast reconstruction over a 5-year period (2015–2020). Forty-one (61.2%) patients received radiotherapy (RT group), and twenty-six (38.8%) did not (non-RT group). Data regarding patients, oncological therapies, type of reconstruction, time of hospitalization, complications, and costs were collected. The statistical analysis was performed using IBM SPSS Statistics 25. General complications were noted for 18 patients (43.9%) in the RT group and for 7 patients (26.9%) in the non-RT group. Major complications were observed only in the first group (five patients–12.2%). The mean time of hospitalization in the RT group was 14.83 days for patients with complications versus 9.83 days for those without complications and 15.5 days versus 8.63 days, respectively, in the non-RT group. The mean cost for patients without complications was 235.64 euros, whereas the cost for patients with complications was 330.24 euros (p = 0.001). Radiation therapy can affect the overall outcome by increasing the risk of complications and increasing costs; however, our paper shows that the association of alloplastic reconstruction in patients with radiotherapy can be performed safely and with low costs in carefully selected patients

Novel Coatings for Superhydrophobic/Superamphiphobic Surfaces with Tunable Morphology of Nanoparticles

Functional surfaces with special wettability properties are currently receiving a lot of attention [...