C. Dong, Jiangbo Luo, Gang Chen, Wei Chen, Xinghua Xiao
A facile, effective and green method using Ginkgo Biloba leaf extract was applied and optimized for the preparation of well dispersed silver nanoparticles. In the method, Ginkgo Biloba leaf extract was employed as both stabilizing and reducing agent without the addition of a toxic agent. 0.1 % silver nitrate solution (w/v) was used silver source. The synthesized silver nanoparticles were investigated and examined by UV-vis absorption spectroscopy (UV-vis), Scanning electron microscope (SEM), Transmission electron microscopy (TEM), powder X-ray diffraction (XRD) and Dynamic light scattering (DLS). The formation of silver nanoparticles was found by a change of color from light yellow to red, which was further proved by absorbance peak at 456 nm in UV-vis spectroscopy. The prepared nanoparticles are global in shape, highly crystalline in nature with a narrow distribution from 10 nm to 40 nm. The silver nanoparticles were capped with extracts, which prevented them from agglomeration and oxidation. Different parameters affecting the generation performance of silver nanoparticles, such as time, amount of silver nitrate and extract were investigated. The results demonstrate that these reaction parameters play important roles in the synthesis of silver nanoparticles.
{"title":"Green Synthesis and Characterization of Silver Nanoparticles Using Ginkgo Biloba Laf Extract","authors":"C. Dong, Jiangbo Luo, Gang Chen, Wei Chen, Xinghua Xiao","doi":"10.5755/j02.ms.32876","DOIUrl":"https://doi.org/10.5755/j02.ms.32876","url":null,"abstract":"A facile, effective and green method using Ginkgo Biloba leaf extract was applied and optimized for the preparation of well dispersed silver nanoparticles. In the method, Ginkgo Biloba leaf extract was employed as both stabilizing and reducing agent without the addition of a toxic agent. 0.1 % silver nitrate solution (w/v) was used silver source. The synthesized silver nanoparticles were investigated and examined by UV-vis absorption spectroscopy (UV-vis), Scanning electron microscope (SEM), Transmission electron microscopy (TEM), powder X-ray diffraction (XRD) and Dynamic light scattering (DLS). The formation of silver nanoparticles was found by a change of color from light yellow to red, which was further proved by absorbance peak at 456 nm in UV-vis spectroscopy. The prepared nanoparticles are global in shape, highly crystalline in nature with a narrow distribution from 10 nm to 40 nm. The silver nanoparticles were capped with extracts, which prevented them from agglomeration and oxidation. Different parameters affecting the generation performance of silver nanoparticles, such as time, amount of silver nitrate and extract were investigated. The results demonstrate that these reaction parameters play important roles in the synthesis of silver nanoparticles.","PeriodicalId":49875,"journal":{"name":"Materials Science-Poland","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47569394","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Guru Sampath Kumar Ankisetty, Vijay Kumar Jinde, M. Ungarala, S. Pendyala, Obulapathi Lavuluri, Sharon Samyuktha Vadde
Sr0.2Zn0.8TiO3 (SZT) ternary nanopowders of perovskite structure samples were prepared by conventional solid state reaction technique using ultra-pure metal oxide powders. SrCO3, ZnO and TiO2 powders were used as a source of Strontium, Zinc, and Titanium. The calcination temperature of the samples is 820 °C and sintered at different temperatures ranging from 850 °C to 1000 °C in conventional and microwave furnaces for 2 hours and 30 min., respectively. The synthesized nano-powders were characterized using XRD, SEM, XPS and their dielectric properties were studied by temperature dependent LCR meter. The dielectric constant increases with an increase in sintering temperature until 950 °C and it decreases with a further increase of frequency.
{"title":"Microwave Assisted Sintering of Sr-doped Zinc Titanate (Sr0.2Zn0.8TiO3) Nano-ceramics","authors":"Guru Sampath Kumar Ankisetty, Vijay Kumar Jinde, M. Ungarala, S. Pendyala, Obulapathi Lavuluri, Sharon Samyuktha Vadde","doi":"10.5755/j02.ms.33625","DOIUrl":"https://doi.org/10.5755/j02.ms.33625","url":null,"abstract":"Sr0.2Zn0.8TiO3 (SZT) ternary nanopowders of perovskite structure samples were prepared by conventional solid state reaction technique using ultra-pure metal oxide powders. SrCO3, ZnO and TiO2 powders were used as a source of Strontium, Zinc, and Titanium. The calcination temperature of the samples is 820 °C and sintered at different temperatures ranging from 850 °C to 1000 °C in conventional and microwave furnaces for 2 hours and 30 min., respectively. The synthesized nano-powders were characterized using XRD, SEM, XPS and their dielectric properties were studied by temperature dependent LCR meter. The dielectric constant increases with an increase in sintering temperature until 950 °C and it decreases with a further increase of frequency.","PeriodicalId":49875,"journal":{"name":"Materials Science-Poland","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41679829","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study investigated the seismic performance of cementitious grout filled coupler and sleeve connections in precast wall panels under cyclic lateral loading. The effectiveness of these connections in enhancing the seismic performance of precast concrete walls was evaluated. In many countries, grouted coupler connections are the preferred option, whereas sleeve connections were more commonly utilized in India due to the belief that a greater portion of the dowel being grouted enhances structural stability. Tests were conducted on full scale precast wall panels to study the behaviour of connections by applying a displacement-controlled cyclic lateral loading and the results were discussed. The experimental study revealed that the cementitious grout filled coupler connection exhibited better seismic performance and was recommended for precast wall panel connections over the grouted sleeve connection. Compared to the grout filled sleeve connection, the specimen with an unbonded segment demonstrated an 8% rise in energy dissipation, while the specimen with a grouted coupler connection displayed a 55 % increase.
{"title":"Seismic Performance of Cementitious Grout Filled Coupler and Sleeve Connections in Precast Wall Panels under Cyclic Lateral Loading","authors":"Joyson Silva Parisutham, Jaya KRISHNAN PRABHAKARAN, Binu Sukumar","doi":"10.5755/j02.ms.33883","DOIUrl":"https://doi.org/10.5755/j02.ms.33883","url":null,"abstract":"This study investigated the seismic performance of cementitious grout filled coupler and sleeve connections in precast wall panels under cyclic lateral loading. The effectiveness of these connections in enhancing the seismic performance of precast concrete walls was evaluated. In many countries, grouted coupler connections are the preferred option, whereas sleeve connections were more commonly utilized in India due to the belief that a greater portion of the dowel being grouted enhances structural stability. Tests were conducted on full scale precast wall panels to study the behaviour of connections by applying a displacement-controlled cyclic lateral loading and the results were discussed. The experimental study revealed that the cementitious grout filled coupler connection exhibited better seismic performance and was recommended for precast wall panel connections over the grouted sleeve connection. Compared to the grout filled sleeve connection, the specimen with an unbonded segment demonstrated an 8% rise in energy dissipation, while the specimen with a grouted coupler connection displayed a 55 % increase.","PeriodicalId":49875,"journal":{"name":"Materials Science-Poland","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45387042","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Martin Charles Mark, Satish Kumar Shanmugam, Ramadoss Rajendran
This study explores the novel design of geometric rubbing profiles on rotary friction welding for enhanced mechanical clamping in joining dissimilar alloys such as copper and stainless steel 316L. The clamping behavior of rubbing profiles could hold the yielding of the weld joint to a maximum level. An innovative approach to effective mixing of the weldment zone could be achieved through the definition of rubbing profiles. The effective dispersion of dissimilar metallic phases could be governed by the geometrical profile in achieving the intermetallic SS-Cu phase. Variations were made in welding parameters like tool rotational speed, upset pressure, upset time, friction pressure, and friction time to find the appropriate process for the four different rubbing profiles, namely helical fluke, plus, cylindrical, and flat to achieve a reduction in micro and macro-structural defects with strong weld nugget. Results show that helical fluke rubbing profiles were seen to have explicit values like ultimate tensile strength of 217 MPa (upset pressure), elongation of 9.8 % (upset pressure), and average hardness of 125 HV (friction pressure) at the weld nugget. Microstructural characteristics prove that the formation of IMCs through grain size reduction such as cementite increases the Vickers hardness of the weldment.
{"title":"Mechanical and Microstructural Characteristics of Rotary Friction Welded SS316L and Pure Copper with Added MWCNT Nano Additives","authors":"Martin Charles Mark, Satish Kumar Shanmugam, Ramadoss Rajendran","doi":"10.5755/j02.ms.33038","DOIUrl":"https://doi.org/10.5755/j02.ms.33038","url":null,"abstract":"This study explores the novel design of geometric rubbing profiles on rotary friction welding for enhanced mechanical clamping in joining dissimilar alloys such as copper and stainless steel 316L. The clamping behavior of rubbing profiles could hold the yielding of the weld joint to a maximum level. An innovative approach to effective mixing of the weldment zone could be achieved through the definition of rubbing profiles. The effective dispersion of dissimilar metallic phases could be governed by the geometrical profile in achieving the intermetallic SS-Cu phase. Variations were made in welding parameters like tool rotational speed, upset pressure, upset time, friction pressure, and friction time to find the appropriate process for the four different rubbing profiles, namely helical fluke, plus, cylindrical, and flat to achieve a reduction in micro and macro-structural defects with strong weld nugget. Results show that helical fluke rubbing profiles were seen to have explicit values like ultimate tensile strength of 217 MPa (upset pressure), elongation of 9.8 % (upset pressure), and average hardness of 125 HV (friction pressure) at the weld nugget. Microstructural characteristics prove that the formation of IMCs through grain size reduction such as cementite increases the Vickers hardness of the weldment.","PeriodicalId":49875,"journal":{"name":"Materials Science-Poland","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42866272","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper provides electrical characterization of single layer graphene ribbon devices defined as back-gated graphene transistors. The two-terminal back-gated graphene ribbon devices were fabricated on a conventional Si substrate covered by a 90 nm-thick thermal SiO2. The chemical vapor deposition process was used for the graphene layer deposition and its quality was checked with optical microscopy, scanning electron microscopy and Raman spectroscopy. For the device fabrication, optical lithography was used for electrode patterns through a mask, and Ti/Au (10 nm/100 nm) metallic contacts were deposited by thermal evaporation. We report low and high field electrical measurements of several devices, under a controlled environment over a wide temperature range, from 77 to 300 K. At 77 K, the drain current decreases, i.e. the resistance of the graphene increases, and the nonlinearity is still present. The maximum influence of the temperature is reached at the charges neutrality point, and we observe that the temperature could influence the position of the charge neutrality point. This indicates that the carriers are thermally activated, which yields a least pronounced current with the increase of the back gate voltage.
{"title":"Electrical Characteristics of Single Layer Graphene Ribbons in a Wide Temperature Range","authors":"Rachid Fates, R. Remmouche, T. Benkedidah","doi":"10.5755/j02.ms.33700","DOIUrl":"https://doi.org/10.5755/j02.ms.33700","url":null,"abstract":"This paper provides electrical characterization of single layer graphene ribbon devices defined as back-gated graphene transistors. The two-terminal back-gated graphene ribbon devices were fabricated on a conventional Si substrate covered by a 90 nm-thick thermal SiO2. The chemical vapor deposition process was used for the graphene layer deposition and its quality was checked with optical microscopy, scanning electron microscopy and Raman spectroscopy. For the device fabrication, optical lithography was used for electrode patterns through a mask, and Ti/Au (10 nm/100 nm) metallic contacts were deposited by thermal evaporation. We report low and high field electrical measurements of several devices, under a controlled environment over a wide temperature range, from 77 to 300 K. At 77 K, the drain current decreases, i.e. the resistance of the graphene increases, and the nonlinearity is still present. The maximum influence of the temperature is reached at the charges neutrality point, and we observe that the temperature could influence the position of the charge neutrality point. This indicates that the carriers are thermally activated, which yields a least pronounced current with the increase of the back gate voltage.","PeriodicalId":49875,"journal":{"name":"Materials Science-Poland","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46009484","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-01DOI: 10.31044/1684-579x-2023-0-7-30-39
P. Onishchenko, T. Glushkova, A. Kostyunin, M. Rezvova, T. Akentyeva, L. Barbarash
The physical-mechanical characteristics of materials-components of bioprostheses of heart valves presented in clinical practice in Russia, with subsequent adaptation of properties for numerical modeling tasks, have been obtained and generalized. It is shown that all the studied materials have a pronounced nonlinearity and can be represented only in the form of polynomial models. Comparison of the results of computer modeling based on the obtained coefficients of materials showed no differences with the data of full-scale bench tests, which made possible to verify computer models.
{"title":"Computer models of biomaterials used for manufacture of flap apparatus of prosthetic heart valves","authors":"P. Onishchenko, T. Glushkova, A. Kostyunin, M. Rezvova, T. Akentyeva, L. Barbarash","doi":"10.31044/1684-579x-2023-0-7-30-39","DOIUrl":"https://doi.org/10.31044/1684-579x-2023-0-7-30-39","url":null,"abstract":"The physical-mechanical characteristics of materials-components of bioprostheses of heart valves presented in clinical practice in Russia, with subsequent adaptation of properties for numerical modeling tasks, have been obtained and generalized. It is shown that all the studied materials have a pronounced nonlinearity and can be represented only in the form of polynomial models. Comparison of the results of computer modeling based on the obtained coefficients of materials showed no differences with the data of full-scale bench tests, which made possible to verify computer models.","PeriodicalId":49875,"journal":{"name":"Materials Science-Poland","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41451374","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Cement-based cementitious materials present an alkaline environment and mainly exist in the form of Ca(OH)2. Phosphogypsum, as a retarder of cementitious materials, is often added to cement instead of gypsum, and the fluorine by-product of phosphogypsum is also fixed in the form of CaF2. These cement-based materials often serve in environments containing carbonate groundwater, which changes the stability of solidified CaF2. This paper studied the solid and liquid changes in Ca(OH)2-CaF2, Ca(OH)2-CaF2-HCO3, CaF2-HCO3-OH systems, and therefore studied the solubility of the by-product CaF2 of phosphogypsum in the groundwater containing HCO3- anion after curing in the cement-based cementitious system through experiments and thermodynamic equation simulation. The results showed that the dissolved Ca2+ of Ca(OH)2 led to the dissolution of CaF2, which led to a significant reduction in the F- anion concentration. However, with the increase of HCO3- concentration in groundwater, the F- anion concentration of Ca(OH)2-CaF2-HCO3 system increased, and the main product formed in the solid phase was calcium carbonate; The dissolution of F- anions in CaF2-HCO3-OH system also increased with the increase of HCO3- concentration. Therefore, the influence of HCO3- in groundwater should be considered when using phosphogypsum instead of gypsum as a retarder in cement-based cementitious materials.
{"title":"Thermodynamic Stability and Dissolution of Calcium Fluoride of Phosphogypsum Solidified in Cement-Based Cementing Materials in Bicarbonate Solution","authors":"Jianhui Fan, Xuebing Wang, Shengbo Guo","doi":"10.5755/j02.ms.33694","DOIUrl":"https://doi.org/10.5755/j02.ms.33694","url":null,"abstract":"Cement-based cementitious materials present an alkaline environment and mainly exist in the form of Ca(OH)2. Phosphogypsum, as a retarder of cementitious materials, is often added to cement instead of gypsum, and the fluorine by-product of phosphogypsum is also fixed in the form of CaF2. These cement-based materials often serve in environments containing carbonate groundwater, which changes the stability of solidified CaF2. This paper studied the solid and liquid changes in Ca(OH)2-CaF2, Ca(OH)2-CaF2-HCO3, CaF2-HCO3-OH systems, and therefore studied the solubility of the by-product CaF2 of phosphogypsum in the groundwater containing HCO3- anion after curing in the cement-based cementitious system through experiments and thermodynamic equation simulation. The results showed that the dissolved Ca2+ of Ca(OH)2 led to the dissolution of CaF2, which led to a significant reduction in the F- anion concentration. However, with the increase of HCO3- concentration in groundwater, the F- anion concentration of Ca(OH)2-CaF2-HCO3 system increased, and the main product formed in the solid phase was calcium carbonate; The dissolution of F- anions in CaF2-HCO3-OH system also increased with the increase of HCO3- concentration. Therefore, the influence of HCO3- in groundwater should be considered when using phosphogypsum instead of gypsum as a retarder in cement-based cementitious materials.","PeriodicalId":49875,"journal":{"name":"Materials Science-Poland","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41615071","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
N. Mandre, T. Plamus, Angelika Linder, T. Varjas, J. Majak, A. Krumme
The current paper covers an experimental study, mathematical modelling, and design optimization of the laser treatment process of denim fabrics. Laser fading is used in the finishing phase of garment production, unfortunately, it decreases fabric durability. Denim fabric is known as a cotton fabric but nowadays it is blended with other fibres to improve fabric properties. For this reason, the main purpose of this study was to test multicomponent fabric longevity after laser treatment. The knowledge from this study is used by garment production company. The tear force, abrasion resistance, and colour difference are considered as performance characteristics of laser treated denim fabrics subjected to maximization. To achieve the goals, novel, mathematical models were developed. In the preliminary tests, the design space was determined. The full factorial design of experiments was utilized in the experimental study and the values of the performance characteristics are measured. Based on the results of the experimental study the artificial neural network and Haar wavelet based mathematical models were developed to predict the behaviour of the tear force, abrasion resistance, and colour difference. The artificial intelligence-based multicriteria design optimization procedure is developed.
{"title":"Design of Performance Characteristics on Laser Treated Denim Fabric","authors":"N. Mandre, T. Plamus, Angelika Linder, T. Varjas, J. Majak, A. Krumme","doi":"10.5755/j02.ms.33259","DOIUrl":"https://doi.org/10.5755/j02.ms.33259","url":null,"abstract":"The current paper covers an experimental study, mathematical modelling, and design optimization of the laser treatment process of denim fabrics. Laser fading is used in the finishing phase of garment production, unfortunately, it decreases fabric durability. Denim fabric is known as a cotton fabric but nowadays it is blended with other fibres to improve fabric properties. For this reason, the main purpose of this study was to test multicomponent fabric longevity after laser treatment. The knowledge from this study is used by garment production company. The tear force, abrasion resistance, and colour difference are considered as performance characteristics of laser treated denim fabrics subjected to maximization. To achieve the goals, novel, mathematical models were developed. In the preliminary tests, the design space was determined. The full factorial design of experiments was utilized in the experimental study and the values of the performance characteristics are measured. Based on the results of the experimental study the artificial neural network and Haar wavelet based mathematical models were developed to predict the behaviour of the tear force, abrasion resistance, and colour difference. The artificial intelligence-based multicriteria design optimization procedure is developed.","PeriodicalId":49875,"journal":{"name":"Materials Science-Poland","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45699060","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hybrid calcium silicate cements (HCSC) are new bioactive materials of the fourth generation with the main application as pulp capping agents and/or as liners in indirect pulp capping. The aim is to analyze the shear bond strength and the quality of the interface between a composite restorative material and a new bioactive material and other hybrid cements at the same conditions. The used pulp-capping hybrid materials: TheraCal and the new hybrid biomaterial BioCal-Cap. In this study only one type of adhesive system (Scotchbond 3M, St. Paul, MN, US) and resin-based composites (Filtek Ultimate 3M, USA) were used. For this purpose, 60 molds were prepared and divided into 4 groups. Half of them were filled with TheraCal and the other 30 with BioCal-Cap. The shear bond strength between calcium-silicate cements and the composite material was investigated. Mann-Whitney test and Wilcoxon Signed Ranks Test were used for statistical analysis of the results. In both of the materials there was no statistically significant difference in the results after the immediate and postponed placement of the composite material. Nevertheless, in both of them there was a tendency for a slight increase in shear strength in the samples which delayed the application of the restorative material. The novel hybrid material BioCal-Cap was reported to have higher shear strength values (18.06 – 20.25 MPa) at both time periods in comparison to the values for TheraCal (13.71 – 15.58 MPa). The data clearly showed that the time of the composite material placement did not affect the shear bond strength in each of the observed groups. The median value was shifted higher after the immediate composite placement, which supported one-step treatment approach to the novel hybrid material BioCal-Cap, while the TheraCal LC exhibited the opposite tendency. The adhesive layers in both hybrid cements were homogeneous, properly structured, without the presence of microcracks and gaps, and had different thicknesses at different recovery times.
{"title":"Analysis of Shear Bond Strength and the Quality of the Interface Between Composite Resin and Novel Hybrid Calcium Silicate Cements","authors":"Ivanka Dimitrova, Desislava Tsanova-Tosheva","doi":"10.5755/j02.ms.32064","DOIUrl":"https://doi.org/10.5755/j02.ms.32064","url":null,"abstract":"Hybrid calcium silicate cements (HCSC) are new bioactive materials of the fourth generation with the main application as pulp capping agents and/or as liners in indirect pulp capping. The aim is to analyze the shear bond strength and the quality of the interface between a composite restorative material and a new bioactive material and other hybrid cements at the same conditions. The used pulp-capping hybrid materials: TheraCal and the new hybrid biomaterial BioCal-Cap. In this study only one type of adhesive system (Scotchbond 3M, St. Paul, MN, US) and resin-based composites (Filtek Ultimate 3M, USA) were used. For this purpose, 60 molds were prepared and divided into 4 groups. Half of them were filled with TheraCal and the other 30 with BioCal-Cap. The shear bond strength between calcium-silicate cements and the composite material was investigated. Mann-Whitney test and Wilcoxon Signed Ranks Test were used for statistical analysis of the results. In both of the materials there was no statistically significant difference in the results after the immediate and postponed placement of the composite material. Nevertheless, in both of them there was a tendency for a slight increase in shear strength in the samples which delayed the application of the restorative material. The novel hybrid material BioCal-Cap was reported to have higher shear strength values (18.06 – 20.25 MPa) at both time periods in comparison to the values for TheraCal (13.71 – 15.58 MPa). The data clearly showed that the time of the composite material placement did not affect the shear bond strength in each of the observed groups. The median value was shifted higher after the immediate composite placement, which supported one-step treatment approach to the novel hybrid material BioCal-Cap, while the TheraCal LC exhibited the opposite tendency. The adhesive layers in both hybrid cements were homogeneous, properly structured, without the presence of microcracks and gaps, and had different thicknesses at different recovery times.","PeriodicalId":49875,"journal":{"name":"Materials Science-Poland","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48194612","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Titanium oxo clusters are considered a model for nanotitanium dioxide and have gradually become a new field of functional materials in solar cells. In this work, the precise structural information of two types of tartrate-based titanium-oxo clusters was investigated by quantum chemical approaches. Density functional theory (DFT) and time-dependent density functional theory (TDDFT) calculations provided the precise structural parameters of Ti4(C4H2O6)(AS)2(OiPr)10 and Ti4(C4H2O6)(ATS)2(OiPr)10. Our work provided reliable results in agreement with the experimental results. In both molecules, the Ti-O bonds were mainly divided into three categories: the bonds in the first category were the coordination bonds between the central skeleton Ti atom and the tartaric acid group, whose bond lengths were 2.000 – 2.080 Å; the bonds in the second category were the coordination bond formed by the Ti atom and the oxygen on the AS ligand sulphonic acid group, whose bond lengths were 2.148 – 2.310 Å; the bonds in the third category were the Ti-O bonds with shorter bond lengths, which were the coordination bond formed by the Ti atom and the oxygen on the isopropylalkoxy group with their bond lengths in the value range from 1.777 Å to 1.795 Å. These kinds of Ti-O bonds also can be found in other Ti4 titanium-oxo clusters. Molecular orbitals showed that electron transfer from the AS/ATS ligand to the {Ti4} central skeleton was induced by sunlight with maximum UV-Vis absorption of 605/629 nm. Our calculation results provide strong guidance for the discovery of new efficient titanium oxo in solar cells.
{"title":"Structures and Electronic Properties of Titanium Oxo Clusters with Tartrate Ligand: A Density Functional Theory Study","authors":"Jing Huang, Lei Yang, Shasha Zeng","doi":"10.5755/j02.ms.33426","DOIUrl":"https://doi.org/10.5755/j02.ms.33426","url":null,"abstract":"Titanium oxo clusters are considered a model for nanotitanium dioxide and have gradually become a new field of functional materials in solar cells. In this work, the precise structural information of two types of tartrate-based titanium-oxo clusters was investigated by quantum chemical approaches. Density functional theory (DFT) and time-dependent density functional theory (TDDFT) calculations provided the precise structural parameters of Ti4(C4H2O6)(AS)2(OiPr)10 and Ti4(C4H2O6)(ATS)2(OiPr)10. Our work provided reliable results in agreement with the experimental results. In both molecules, the Ti-O bonds were mainly divided into three categories: the bonds in the first category were the coordination bonds between the central skeleton Ti atom and the tartaric acid group, whose bond lengths were 2.000 – 2.080 Å; the bonds in the second category were the coordination bond formed by the Ti atom and the oxygen on the AS ligand sulphonic acid group, whose bond lengths were 2.148 – 2.310 Å; the bonds in the third category were the Ti-O bonds with shorter bond lengths, which were the coordination bond formed by the Ti atom and the oxygen on the isopropylalkoxy group with their bond lengths in the value range from 1.777 Å to 1.795 Å. These kinds of Ti-O bonds also can be found in other Ti4 titanium-oxo clusters. Molecular orbitals showed that electron transfer from the AS/ATS ligand to the {Ti4} central skeleton was induced by sunlight with maximum UV-Vis absorption of 605/629 nm. Our calculation results provide strong guidance for the discovery of new efficient titanium oxo in solar cells.","PeriodicalId":49875,"journal":{"name":"Materials Science-Poland","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45464141","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","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：