In the study, heterogeneous radiolysis of water in adsorption and liquid form was studied in the (RaO)x(SiO2)y+H2O system. The effect of radioactivity of radium cations and process temperature on the release of molecular hydrogen was determined (T=300‒673K). The mechanism of heterogeneous radiolysis of water with the participation of the studied system (RaO)x(SiO2)y+H2O has been proposed.
{"title":"Investigation of Radiation-Heterogeneous and Catalytic Processes In The Surface Of (RaO)x(SiO2)y +H2O System","authors":"Z. Mansimov, G. Imanova, A. Garibov, T. Agayev","doi":"10.18596/jotcsa.1118855","DOIUrl":"https://doi.org/10.18596/jotcsa.1118855","url":null,"abstract":"In the study, heterogeneous radiolysis of water in adsorption and liquid form was studied in the (RaO)x(SiO2)y+H2O system. The effect of radioactivity of radium cations and process temperature on the release of molecular hydrogen was determined (T=300‒673K). The mechanism of heterogeneous radiolysis of water with the participation of the studied system (RaO)x(SiO2)y+H2O has been proposed.","PeriodicalId":17299,"journal":{"name":"Journal of the Turkish Chemical Society Section A: Chemistry","volume":"12 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81804637","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. J. Paul, Sarvesh Kumar Singh, Jaya Tuteja, A. Sand, P. Chandra
The tremendous interest for robust, clean energy storage devices to comprehend the growing needs of modern gadgets has led to exploration of materials having unprecedented electrochemical and interfacial properties. Here, the present study deals with the synergistic effects of multi walled carbon nanotubes and polyaniline nanocomposites on the electro-chemical and thermal properties for wide-range of applications. The microstructural, structural, and optical characterizations have been evaluated through scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and UV-Vis spectrophotometry. The thermal stability of the product was also studied through thermal gravimetric analysis (TGA) and the room temperature electrical conductivity was also measured. An exceptional enhancement in thermal stability and conductivity has been observed apparently due to interfacial properties of polyaniline (PANI) and multiwalled carbon nanotubes (MWCNTs). Further, in present study we are going to report a comparative analysis of thermal and electrical properties of PANI/MWCNT nanocomposites with different loadings of MWCNTs. The room temperature conductivity as calculated for 1%, 2%, 4% and 8% MWCNT loading is around 2.019, 3.075, 4.48, 8.73 S/cm respectively. The mechanism for thermal and electrical enhancements in PANI-coated MWCNT nanocomposites is also expounded.
{"title":"Probing the Electro-Chemical and Thermal Properties of Polyaniline/MWCNT Nanocomposites","authors":"S. J. Paul, Sarvesh Kumar Singh, Jaya Tuteja, A. Sand, P. Chandra","doi":"10.18596/jotcsa.1177040","DOIUrl":"https://doi.org/10.18596/jotcsa.1177040","url":null,"abstract":"The tremendous interest for robust, clean energy storage devices to comprehend the growing needs of modern gadgets has led to exploration of materials having unprecedented electrochemical and interfacial properties. Here, the present study deals with the synergistic effects of multi walled carbon nanotubes and polyaniline nanocomposites on the electro-chemical and thermal properties for wide-range of applications. The microstructural, structural, and optical characterizations have been evaluated through scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and UV-Vis spectrophotometry. The thermal stability of the product was also studied through thermal gravimetric analysis (TGA) and the room temperature electrical conductivity was also measured. An exceptional enhancement in thermal stability and conductivity has been observed apparently due to interfacial properties of polyaniline (PANI) and multiwalled carbon nanotubes (MWCNTs). Further, in present study we are going to report a comparative analysis of thermal and electrical properties of PANI/MWCNT nanocomposites with different loadings of MWCNTs. The room temperature conductivity as calculated for 1%, 2%, 4% and 8% MWCNT loading is around 2.019, 3.075, 4.48, 8.73 S/cm respectively. The mechanism for thermal and electrical enhancements in PANI-coated MWCNT nanocomposites is also expounded.","PeriodicalId":17299,"journal":{"name":"Journal of the Turkish Chemical Society Section A: Chemistry","volume":"4 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87463184","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mehtap Tugrak Sakarya, H. I. Gül, C. Yamali, Parham Taslimi, Tuğba Taşkın Tok
Alzheimer's disease (AD) and diabetes mellitus (DM) are related to abnormal changes in enzyme activity. While acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) are the primary targets in the treatment of Alzheimer's disease (AD), α-glucosidase (α-Gly) and α-amylase (α-Amy) enzymes are known for diabetes mellitus (DM). Here, benzenesulfonamide-based thiourea and thiazolidinone derivatives such as AChE, BChE, α-Gly, and α-Amy inhibitors were reported. The results revealed that compounds 1d and 2c showed promising AChE and BChE inhibition effects. Compound 2a was the most potent inhibitor against α-glycosidase and α-amylase, respectively. Molecular docking studies indicated that the lead compounds' binding energy values and molecular interactions were better than that of tacrine and acarbose. The most bioactive compounds may be considered potent leads for further studies.
{"title":"Molecular docking studies and biological activities of benzenesulfonamide-based thiourea and thiazolidinone derivatives targeting cholinesterases, α-glucosidase, and α-amylase enzymes","authors":"Mehtap Tugrak Sakarya, H. I. Gül, C. Yamali, Parham Taslimi, Tuğba Taşkın Tok","doi":"10.18596/jotcsa.1111172","DOIUrl":"https://doi.org/10.18596/jotcsa.1111172","url":null,"abstract":"Alzheimer's disease (AD) and diabetes mellitus (DM) are related to abnormal changes in enzyme activity. While acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) are the primary targets in the treatment of Alzheimer's disease (AD), α-glucosidase (α-Gly) and α-amylase (α-Amy) enzymes are known for diabetes mellitus (DM). Here, benzenesulfonamide-based thiourea and thiazolidinone derivatives such as AChE, BChE, α-Gly, and α-Amy inhibitors were reported. The results revealed that compounds 1d and 2c showed promising AChE and BChE inhibition effects. Compound 2a was the most potent inhibitor against α-glycosidase and α-amylase, respectively. Molecular docking studies indicated that the lead compounds' binding energy values and molecular interactions were better than that of tacrine and acarbose. The most bioactive compounds may be considered potent leads for further studies.","PeriodicalId":17299,"journal":{"name":"Journal of the Turkish Chemical Society Section A: Chemistry","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76777149","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ekhlas ABD ALKAREEM, Nuha FARHAN ABD AL-KARİM, Israa I Mahmoud
The goal of the current work is to synthesize methyldopa derivatives. Based on these reactions, two easy, speedy, accurate, inexpensive, and sensitive spectrophotometric approaches have been established for determining methyldopa (MED) in both pure and pharmaceutical forms. The proposed azo-coupling method depends on forming an azo compound between methyldopa drug and 2-AMPY or ANTH to produce two compounds of MED-2AMPY and MED-ANTH in the alkaline medium. The characterization of synthesized compounds utilizing UV-Visible and FT-IR spectra. FT-IR spectra of 2AMPY-MED confirm the existence of OH, C-Hor, C-Hal, NH, N=N, C=O, and C=C vibration at 3455, 3059, 2973, 3100, 1476,1692, and 1560 cm-1, and FT-IR spectra of ANTH-MED confirm the existence of OH, C-Hor, NH, C=O and N=N vibration at 3490, 3050, 3100, 1701 and 1462 cm-1, correspondingly. The obtained color of azo compounds is spectrophotometrically measured for the previously mentioned azo compounds at 450 and 455 nm, respectively. Under perfect conditions, the azo compound solutions exhibited molar absorptivities of 1563.0058 and 2091.0285 L.mol-1.cm-1, Sandell's sensitivity of 0.135 and 0.10 µg.cm-1, and Beer-Lambert's law are obeyed over the ranges 6.25- 62.5 mg. L-1 for the two developed procedures, respectively.
{"title":"Synthesis of New Azo Compounds and Their Application for a Simple Spectrophotometric Determination of Methyldopa Drug Using Anthranilic Acid and 2-Aminopyrimidine as Reagents","authors":"Ekhlas ABD ALKAREEM, Nuha FARHAN ABD AL-KARİM, Israa I Mahmoud","doi":"10.18596/jotcsa.1234028","DOIUrl":"https://doi.org/10.18596/jotcsa.1234028","url":null,"abstract":"The goal of the current work is to synthesize methyldopa derivatives. Based on these reactions, two easy, speedy, accurate, inexpensive, and sensitive spectrophotometric approaches have been established for determining methyldopa (MED) in both pure and pharmaceutical forms. The proposed azo-coupling method depends on forming an azo compound between methyldopa drug and 2-AMPY or ANTH to produce two compounds of MED-2AMPY and MED-ANTH in the alkaline medium. The characterization of synthesized compounds utilizing UV-Visible and FT-IR spectra. FT-IR spectra of 2AMPY-MED confirm the existence of OH, C-Hor, C-Hal, NH, N=N, C=O, and C=C vibration at 3455, 3059, 2973, 3100, 1476,1692, and 1560 cm-1, and FT-IR spectra of ANTH-MED confirm the existence of OH, C-Hor, NH, C=O and N=N vibration at 3490, 3050, 3100, 1701 and 1462 cm-1, correspondingly. The obtained color of azo compounds is spectrophotometrically measured for the previously mentioned azo compounds at 450 and 455 nm, respectively. Under perfect conditions, the azo compound solutions exhibited molar absorptivities of 1563.0058 and 2091.0285 L.mol-1.cm-1, Sandell's sensitivity of 0.135 and 0.10 µg.cm-1, and Beer-Lambert's law are obeyed over the ranges 6.25- 62.5 mg. L-1 for the two developed procedures, respectively.","PeriodicalId":17299,"journal":{"name":"Journal of the Turkish Chemical Society Section A: Chemistry","volume":"9 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89031959","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
R. K, Deevan Paul Amarnath, Hariraj Narayanan, Adhya Das
Countless bioactive compounds are having the oxadiazole nucleus showing clinical and biological applications. Oxadiazole is a heterocyclic compound of the azole family that has gained increasing attention due to its wide therapeutic potential. Many significant synthetic medicinal compounds have the oxadiazole scaffold, which provided a good treatment idea and binds with high affinity to a variety of receptors to aid in the development of novel beneficial derivatives. Numerous researchers have worked to create novel oxadiazole compounds and evaluate them for how they affect inflammation, tumor, epilepsy, microbial infections, and analgesic properties. The present review article summarizes some of the oxadiazole derivatives synthesized and their biological activities and can be a useful guide for researchers working on this scaffold.
{"title":"The Biological Potential and Synthetic Diversity of 1,3,4-Oxadiazole Multiplexed with Various Heterocyclic Compounds","authors":"R. K, Deevan Paul Amarnath, Hariraj Narayanan, Adhya Das","doi":"10.18596/jotcsa.1202640","DOIUrl":"https://doi.org/10.18596/jotcsa.1202640","url":null,"abstract":"Countless bioactive compounds are having the oxadiazole nucleus showing clinical and biological applications. Oxadiazole is a heterocyclic compound of the azole family that has gained increasing attention due to its wide therapeutic potential. Many significant synthetic medicinal compounds have the oxadiazole scaffold, which provided a good treatment idea and binds with high affinity to a variety of receptors to aid in the development of novel beneficial derivatives. Numerous researchers have worked to create novel oxadiazole compounds and evaluate them for how they affect inflammation, tumor, epilepsy, microbial infections, and analgesic properties. The present review article summarizes some of the oxadiazole derivatives synthesized and their biological activities and can be a useful guide for researchers working on this scaffold.","PeriodicalId":17299,"journal":{"name":"Journal of the Turkish Chemical Society Section A: Chemistry","volume":"19 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73700885","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Devi Permatasari, Anisyah IS PURWATİ, Hismiaty Bahua, A. Supriyono
Gynura procumbens is known as one of the herbal medicinal plants found in Indonesia and has been used from time to time. It is claimed to have various efficacy such as anti-hyperglycemic, anti-hypertension, anti-microbial, anti-cancer, and antioxidant. Other studies mention that G. procumbens possessed high antioxidant compounds and had been used as a natural-based medicinal supplement. However, further studies on optimizing the extraction process of Gynura procumbens in Indonesia have yet to be reported. Therefore, this study aimed to optimize the extraction condition of G. procumbens leaves by maceration with three variables: solvent concentration, extraction time, and the ratio of solid-liquid used. Each of those variables contained three different levels. Determination of total flavonoid and antioxidant activity was measured using aluminium chloride colourimetric assay and 2, 2-diphenyl-1-picryl-hydrazil (DPPH) assay, respectively. In the optimization process, Response Surface Methodology (RSM) was used to explore the main effects and interaction between parameters and their correlations with dependent variables. The results were analyzed using the Box-Behnken method using Minitab software 17. This study shows that the most significant effect of the variable for both flavonoid and antioxidant activity was solvent concentration, with a P<0.05. The results showed that the extraction process to obtain G. procumbens extract with optimal flavonoid content and antioxidant activity (IC50) was predicted at 70% solvent concentration, 1 h maceration time, and a solid-liquid ratio of 1:9.8 w/v, with results of 17.599 mg QE/g extract and 0.211 mg/mL, respectively. This study was expected to complement other studies and can be used as an additional reference for the development of the extraction process on a larger scale.
{"title":"Optimization of extraction condition of Gynura procumbens extract enriched with flavonoid and antioxidant compounds using Response Surface Methodology","authors":"Devi Permatasari, Anisyah IS PURWATİ, Hismiaty Bahua, A. Supriyono","doi":"10.18596/jotcsa.1172970","DOIUrl":"https://doi.org/10.18596/jotcsa.1172970","url":null,"abstract":"Gynura procumbens is known as one of the herbal medicinal plants found in Indonesia and has been used from time to time. It is claimed to have various efficacy such as anti-hyperglycemic, anti-hypertension, anti-microbial, anti-cancer, and antioxidant. Other studies mention that G. procumbens possessed high antioxidant compounds and had been used as a natural-based medicinal supplement. However, further studies on optimizing the extraction process of Gynura procumbens in Indonesia have yet to be reported. Therefore, this study aimed to optimize the extraction condition of G. procumbens leaves by maceration with three variables: solvent concentration, extraction time, and the ratio of solid-liquid used. Each of those variables contained three different levels. Determination of total flavonoid and antioxidant activity was measured using aluminium chloride colourimetric assay and 2, 2-diphenyl-1-picryl-hydrazil (DPPH) assay, respectively. In the optimization process, Response Surface Methodology (RSM) was used to explore the main effects and interaction between parameters and their correlations with dependent variables. The results were analyzed using the Box-Behnken method using Minitab software 17. This study shows that the most significant effect of the variable for both flavonoid and antioxidant activity was solvent concentration, with a P<0.05. The results showed that the extraction process to obtain G. procumbens extract with optimal flavonoid content and antioxidant activity (IC50) was predicted at 70% solvent concentration, 1 h maceration time, and a solid-liquid ratio of 1:9.8 w/v, with results of 17.599 mg QE/g extract and 0.211 mg/mL, respectively. This study was expected to complement other studies and can be used as an additional reference for the development of the extraction process on a larger scale.","PeriodicalId":17299,"journal":{"name":"Journal of the Turkish Chemical Society Section A: Chemistry","volume":"16 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74623218","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
K. Nikolova, T. Eftimov, Aleksandar Pashev, M. Karadjov, Christina Tzvetkova, G. Gentscheva, D. Brabant, Fouzar Samia
The aggregate of various chemical substances useful for the functioning of the human body are known as nutrients. Spirulina has been present in human nutrition since ancient times, but in recent years the interest in it has been particularly increased due to the emergence of numerous alternative methods of nutrition. This study aimed to compare the functional and elemental composition as well as the optical properties of commercial Spirulina products available on the Bulgarian market. For this purpose, fluorescence spectroscopy in the ultraviolet and visible range, fourier transform infrared spectroscopy and inductively coupled plasma optical emission spectroscopy were used. The basic components of the analyzed Spirulina samples are proteins (1657 and 1537 cm-1) and carbohydrates (1069 and 1054 cm-1) and no meaningful differences between the IR spectra of the samples. Concentrations of important microelements Mg, Fe, Cu, Zn, and Mn varies with the manufacturer. The highest levels for Mg (6.69 g kg-1) were measured in samples from USA, while the Spirulina fabricated in Bulgaria exhibits the highest contents of Zn (242 mg kg-1) and Cu (25.4 mg kg-1). All samples followed the tendency Mg>Fe>Mn>Zn>Cu. Making use of a fiber optic spectrometer the fluorescence spectra of the studied samples of Spirulina platensis for an excitation wavelength of 380 nm were measured. In these spectra we observe three fluorescence maxima: at 465 nm – nicotinamide dinucleotide phosphate, 640 nm chlorophyll a, and 736 nm due to similar to chlorophyll pigments. A strong positive correlation between the contents of Zn and Cu on the one side and the second fluorescence peak (λ=640 nm) for excitation wavelength at 380 nm. In contrast, a high negative correlation for Fe and the third fluorescence maximum (λ= 736nm) is observed for all excitation wavelengths. The correlation dependencies were obtained with the least squares method with a significance level of p ≤ 0.05.
{"title":"Correlation between chemical characteristics and optical spectra of Spirulina commercially available on the Bulgarian market","authors":"K. Nikolova, T. Eftimov, Aleksandar Pashev, M. Karadjov, Christina Tzvetkova, G. Gentscheva, D. Brabant, Fouzar Samia","doi":"10.18596/jotcsa.1207682","DOIUrl":"https://doi.org/10.18596/jotcsa.1207682","url":null,"abstract":"The aggregate of various chemical substances useful for the functioning of the human body are known as nutrients. Spirulina has been present in human nutrition since ancient times, but in recent years the interest in it has been particularly increased due to the emergence of numerous alternative methods of nutrition. This study aimed to compare the functional and elemental composition as well as the optical properties of commercial Spirulina products available on the Bulgarian market. For this purpose, fluorescence spectroscopy in the ultraviolet and visible range, fourier transform infrared spectroscopy and inductively coupled plasma optical emission spectroscopy were used. The basic components of the analyzed Spirulina samples are proteins (1657 and 1537 cm-1) and carbohydrates (1069 and 1054 cm-1) and no meaningful differences between the IR spectra of the samples. Concentrations of important microelements Mg, Fe, Cu, Zn, and Mn varies with the manufacturer. The highest levels for Mg (6.69 g kg-1) were measured in samples from USA, while the Spirulina fabricated in Bulgaria exhibits the highest contents of Zn (242 mg kg-1) and Cu (25.4 mg kg-1). All samples followed the tendency Mg>Fe>Mn>Zn>Cu. Making use of a fiber optic spectrometer the fluorescence spectra of the studied samples of Spirulina platensis for an excitation wavelength of 380 nm were measured. In these spectra we observe three fluorescence maxima: at 465 nm – nicotinamide dinucleotide phosphate, 640 nm chlorophyll a, and 736 nm due to similar to chlorophyll pigments. A strong positive correlation between the contents of Zn and Cu on the one side and the second fluorescence peak (λ=640 nm) for excitation wavelength at 380 nm. In contrast, a high negative correlation for Fe and the third fluorescence maximum (λ= 736nm) is observed for all excitation wavelengths. The correlation dependencies were obtained with the least squares method with a significance level of p ≤ 0.05.","PeriodicalId":17299,"journal":{"name":"Journal of the Turkish Chemical Society Section A: Chemistry","volume":"9 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84998365","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The study reports the structural and spectroscopic properties of Nd3+ doped lead metatantalate phosphor series fabricated by conventional solid state method. XRD results of the PbTa2O6 phase confirm the tungsten bronze symmetry and single-phase structure between 0.5 and 10 mol% Nd3+ concentrations. The lead decrease in the structure can be associated with maintaining the charge balance and single phase due to evaporation during sintering. In SEM micrographs, the grains exhibited shapeless morphology, and the grain sizes varied from 0.5 to 7 m. In EDS results, the increase of Ta/Pb ratio in grain surfaces indicated some lead evaporation, as reported in previous studies. The absorption spectrum of PbTa2O6 host peaked around 275-280 nm, and the band gap was found to be 3.7±0.2 eV. The absorptions of Nd3+ doped phophors shifted the high wavelenght or the low band gap, where the band gaps were found between 3.1±0.2 and 3.3±0.2 eV. The PL emissions of the phosphors in near-inrared region were observed with the transitions of 4F3/2→4I9/2 (at 875 nm) and 4F3/2→4I11/2 (at 1060 nm) of Nd3+. The RL emissions or X-ray excited luminescence were monitored with the transitions of 4F3/2→4I9/2 (at 875 nm), 4F3/2→4I11/2 (at 1065 nm) in the infrared region, and the transitions of 2F(2)5/2→4F9/2, 2F(2)5/2→2H(2)11/2, 2F(2)5/2→4G5/2, 2F(2)5/2→4G7/2, 2F(2)5/2→4G9/2 in the visible region corresponding to at around 430, 455, 490, 525, and 570 nm, respectively. PL and RL emissions of the phosphors exhibited the decreasing emission intensity over 5 mol% due to the concentration quenching which may be associated with cross-relaxing mechanism. In the PL and RL spectral profiles, the similarity of splitting levels was attributed to the similarity of the local symmetry of the ligand ions surrounding the Nd3+ ion. The CIE coordinates obtained using RL emissions were found close to the blue region due to visible region transitions.
{"title":"Evaluation of the Structural, Near-Infrared Luminescence, and Radioluminescence Properties of Nd3+ Activated TTB-Lead Metatantalate Phosphors","authors":"M. İlhan, İ. Keskin","doi":"10.18596/jotcsa.1216564","DOIUrl":"https://doi.org/10.18596/jotcsa.1216564","url":null,"abstract":"The study reports the structural and spectroscopic properties of Nd3+ doped lead metatantalate phosphor series fabricated by conventional solid state method. XRD results of the PbTa2O6 phase confirm the tungsten bronze symmetry and single-phase structure between 0.5 and 10 mol% Nd3+ concentrations. The lead decrease in the structure can be associated with maintaining the charge balance and single phase due to evaporation during sintering. In SEM micrographs, the grains exhibited shapeless morphology, and the grain sizes varied from 0.5 to 7 m. In EDS results, the increase of Ta/Pb ratio in grain surfaces indicated some lead evaporation, as reported in previous studies. The absorption spectrum of PbTa2O6 host peaked around 275-280 nm, and the band gap was found to be 3.7±0.2 eV. The absorptions of Nd3+ doped phophors shifted the high wavelenght or the low band gap, where the band gaps were found between 3.1±0.2 and 3.3±0.2 eV. The PL emissions of the phosphors in near-inrared region were observed with the transitions of 4F3/2→4I9/2 (at 875 nm) and 4F3/2→4I11/2 (at 1060 nm) of Nd3+. The RL emissions or X-ray excited luminescence were monitored with the transitions of 4F3/2→4I9/2 (at 875 nm), 4F3/2→4I11/2 (at 1065 nm) in the infrared region, and the transitions of 2F(2)5/2→4F9/2, 2F(2)5/2→2H(2)11/2, 2F(2)5/2→4G5/2, 2F(2)5/2→4G7/2, 2F(2)5/2→4G9/2 in the visible region corresponding to at around 430, 455, 490, 525, and 570 nm, respectively. PL and RL emissions of the phosphors exhibited the decreasing emission intensity over 5 mol% due to the concentration quenching which may be associated with cross-relaxing mechanism. In the PL and RL spectral profiles, the similarity of splitting levels was attributed to the similarity of the local symmetry of the ligand ions surrounding the Nd3+ ion. The CIE coordinates obtained using RL emissions were found close to the blue region due to visible region transitions.","PeriodicalId":17299,"journal":{"name":"Journal of the Turkish Chemical Society Section A: Chemistry","volume":"57 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77877907","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Five new Anderson-type polyoxometalate compounds [M((1,10-phen)(OH)x]3[Cr(OH)6Mo6O18]∙16H2O (M=Cr(1), Mn(2), Co(3), Ni(4), Cu(5); x=1,2) were obtained from Na2MoO4∙2H2O and CrCl3∙6H2O within acidic aqueous medium (pH=2-3). The compounds are characterized by means of FT-IR, TGA, ICP-MS, and elemental analysis techniques. The structural analysis show that compounds (1-5) consist of a Anderson-type polyanion [Cr(OH)6Mo6O18]3-.
{"title":"Synthesis and Characterization of New Anderson-Type Polyoxometalates: [M((1,10-phen)(OH)x]3[Cr(OH)6Mo6O18]·16H2O (M=Cr, Mn, Co, Ni, Cu; x=1,2)","authors":"Hülya Avcı Özbek","doi":"10.18596/jotcsa.1215066","DOIUrl":"https://doi.org/10.18596/jotcsa.1215066","url":null,"abstract":"Five new Anderson-type polyoxometalate compounds [M((1,10-phen)(OH)x]3[Cr(OH)6Mo6O18]∙16H2O (M=Cr(1), Mn(2), Co(3), Ni(4), Cu(5); x=1,2) were obtained from Na2MoO4∙2H2O and CrCl3∙6H2O within acidic aqueous medium (pH=2-3). The compounds are characterized by means of FT-IR, TGA, ICP-MS, and elemental analysis techniques. The structural analysis show that compounds (1-5) consist of a Anderson-type polyanion [Cr(OH)6Mo6O18]3-.","PeriodicalId":17299,"journal":{"name":"Journal of the Turkish Chemical Society Section A: Chemistry","volume":"61 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72568196","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Herein, a series of twelve bis-hydrazone substituted isovanilline derivatives 3(a-l), were freshly re-synthesized by the reaction of bis-aldehydes with substituted hydrazide derivatives since these compounds previously showed potent aldose reductase inhibition properties. The obtained compounds were tested for their potential antibacterial and antioxidant activities. In the present study, four different bacterial strains were used, including Gram-positive (Staphylococcus aureus ATCC 29213, Enterococcus faecalis ATCC 29212) and Gram-negative (Pseudomonas aeruginosa ATCC 10231, Escherichia coli ATCC 25912). On the other hand, the antioxidant capacities of freshly re-synthesized bis-hydrazone substituted isovanilline derivatives were determined by using several antioxidant methods, including DPPH free radical scanvenging, TEAC cupric reducing (CUPRAC) and metal chelating activity methods. Several lead molecules were discovered as a potential bacterial inhibitors against S. aureus and E. coli bacterial strains. More specifically, compounds 3g (R=-H) and 3j (R= -4Cl) showed great inhibition properties against E. coli bacterial strains by having MIC values of 1.56 and 6.25 µg/mL, respectively. Moreover, none of the compounds showed potent antioxidant activity against tested methods with respect to compared standards.
{"title":"Antibacterial and Antioxidant Activity Evaluation of Bis-Substituted İsovanillin Derivatives","authors":"Zehra Tekin, Yener Tekeli̇, Zehra Küçükbay, Nebih Lolak, G. Yapar, Suleyman Akocak","doi":"10.18596/jotcsa.1196335","DOIUrl":"https://doi.org/10.18596/jotcsa.1196335","url":null,"abstract":"Herein, a series of twelve bis-hydrazone substituted isovanilline derivatives 3(a-l), were freshly re-synthesized by the reaction of bis-aldehydes with substituted hydrazide derivatives since these compounds previously showed potent aldose reductase inhibition properties. The obtained compounds were tested for their potential antibacterial and antioxidant activities. In the present study, four different bacterial strains were used, including Gram-positive (Staphylococcus aureus ATCC 29213, Enterococcus faecalis ATCC 29212) and Gram-negative (Pseudomonas aeruginosa ATCC 10231, Escherichia coli ATCC 25912). On the other hand, the antioxidant capacities of freshly re-synthesized bis-hydrazone substituted isovanilline derivatives were determined by using several antioxidant methods, including DPPH free radical scanvenging, TEAC cupric reducing (CUPRAC) and metal chelating activity methods. Several lead molecules were discovered as a potential bacterial inhibitors against S. aureus and E. coli bacterial strains. More specifically, compounds 3g (R=-H) and 3j (R= -4Cl) showed great inhibition properties against E. coli bacterial strains by having MIC values of 1.56 and 6.25 µg/mL, respectively. Moreover, none of the compounds showed potent antioxidant activity against tested methods with respect to compared standards.","PeriodicalId":17299,"journal":{"name":"Journal of the Turkish Chemical Society Section A: Chemistry","volume":"43 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77358779","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：