A series of lanthanide binuclear complexes, Ln2（L）6（H2O）4·2H2O（Ln=Sm（Ⅲ）, Gd（Ⅲ）, Er（Ⅲ）, Yb（Ⅲ）, HL=4-quinolinea-carboxylic acid, were synthesized by reactions of corresponding rare earth salts with...A series of lanthanide binuclear complexes, Ln2（L）6（H2O）4·2H2O（Ln=Sm（Ⅲ）, Gd（Ⅲ）, Er（Ⅲ）, Yb（Ⅲ）, HL=4-quinolinea-carboxylic acid, were synthesized by reactions of corresponding rare earth salts with 4-quinolineacarboxylic acid at room temperature and were characterized by elemental analysis, IR spectroscopy, and single-crystal X-ray diffraction.X-ray diffraction analyses showed that they exhibited the same binuclear architecture and crystallized in monoclinic system and P21/c space group.In four complexes, each metal center adopted nine-coordinated mode coordinated by nine O atoms from two H2O molecules and three carboxyls of three ligands, and HL showed three different coordination modes.The variable-temperature magnetic susceptibility showed that complex Gd2（L）6（H2O）4·2H2O performed very weak antiferromagnetic property at low temperature and exchange was almost paramagnetic at high temperature.Complexes Er2（L）6（H2O）4·2H2O and Yb2（L）6（H2O）4·2H2O performed dominating antiferromagnetic coupling.展开更多
The aim of this work was to use cellulose nanocrystals that were obtained by hydrolysis in phosphoric acid solution and further modified with succinic anhydride in the microwave field for PLA reinforcement.A series of...The aim of this work was to use cellulose nanocrystals that were obtained by hydrolysis in phosphoric acid solution and further modified with succinic anhydride in the microwave field for PLA reinforcement.A series of allbionanocomposites containing unmodified and surface modified cellulose nanocrystals with CNC content in the range of 1–3%_(w.t.) were obtained by melt blending and tested by XRD,SEM,DSC and DMA to investigate the effect of surface esterification of CNCs on the structure,morphology,dynamic mechanical properties of bionanocomposites,as well as phase transitions of PLA in the presence of cellulosic nanofiller.DMA investigations showed the highest increase of storage modulus by ca.7%(335 MPa at 25℃)in the glassy state of PLA for 2%_(w.t.)of unmodified CNC.Though,addition of 2%_(w.t.)of succinylated CNCs caused the highest increase of the onset of glass transition temperature(by 6.2℃)thus widening the temperature range of biocomposite application.The increase of glass transition temperature indicates the strongest interfacial interactions due to improved miscibility of surface modified nanocrystals and thus good dispersion of additive in PLA matrix providing high interface.展开更多
Pomegranate flower plant, popularly known using for the treatment of various diseases, was not investigated as a source of dye for cytological studies using human blood cells. The importance of this study is to appear...Pomegranate flower plant, popularly known using for the treatment of various diseases, was not investigated as a source of dye for cytological studies using human blood cells. The importance of this study is to appear dyeing result of pomegranate flower extract on human blood cells. The natural dye source was pomegranate flower known as roselle and potassium aluminum sulfate （alum = KAISO4＇ 12H20） was used as mordant or metal salt. Distilled water was used as solvent. Fresh, clean and air-dried flowers were extracted with distilled water at 100℃ for 30 minutes and then filtered. One drop blood from a healthy 20-year woman was spread as a peripheral on to ten plates and dried at nearly 25℃. These slides were stained by soaking in pomegranate flower extract with/without alum （KA1SO4·12H2O） at 100℃ for 60 minutes. Slides were washed with distilled water, dried and done microscobic examination. The different blood cells dyed dark orange in alum mordant media at 100 ℃. As a result, pomegranate flower has the capacity to use dyeing human blood cells such as eosinophil, basophil and neutrophil.展开更多
Ordered titanium dioxide nanotubes （TiOaNTs） modified with indium tin oxide （ITO） films were obtained via magnetron sputtering, in which ITO plate was used as a target, onto the as-anodized titania support followe...Ordered titanium dioxide nanotubes （TiOaNTs） modified with indium tin oxide （ITO） films were obtained via magnetron sputtering, in which ITO plate was used as a target, onto the as-anodized titania support followed by the calcination process. The morphology of fabricated material with deposited oxide was investigated using scanning electron microscopy. Raman and UV-Vis spectroscopies were utilized to characterize crystalline phase and optical properties of prepared samples, whereas X-ray photoelectron spectroscopy allowed determining the binding energy of present elements. In the case of titanium, three various oxidation states were identified and also the presence of indium and tin was confirmed. The electrochemical test carried out when the sample was exposed to light allows for selection of the most photoactive material. The highest photocurrent was registered when only 5-nm ITO layer was sputtered, and it equals 256 and 133 μA cm^-2 for the electrode material immersed in 0.5 M KOH and K2SO4 electrolytes, respectively, that is accordingly 3.5 and 4.4 times higher than the one observed for pristine titania. Furthermore, ITO-modified titania exhibits excellent photostability upon prolonged illumination that is of key importance for possible application in light-driven processes.展开更多
Succinite,Baltic amber,is one of the most appreciated fossil resins.Its beauty has fascinated people since prehistoric times.It is a substance,and also gemstone,whose uniqueness is due to its compelling,though still n...Succinite,Baltic amber,is one of the most appreciated fossil resins.Its beauty has fascinated people since prehistoric times.It is a substance,and also gemstone,whose uniqueness is due to its compelling,though still not fully understood,physicochemical nature.In this article,some facts about the physical and chemical properties of succinite in order to find an answer for questions about the unique properties of this resin,such as color,transparency,texture etc.,are discussed.These properties are among the factors that determine the choice of Baltic amber as a gemstone.Commonly known properties of succinite,but also some less obvious features,have been linked to the organic and inorganic chemical composition and structural factors,including the sophisticated supramolecular structure masterfully created by nature.Changes of the properties of succinite used as a jewelry stone are discussed as a reflection of changes in its physicochemical nature.In this light,some methods that can be used to identify succinite(i.e.,infrared spectroscopy and nuclear magnetic resonance spectroscopy)and their relevance to the classification of fossil resins are briefly discussed.This article highlights an important point:only by understanding the chemical and physical nature of the material we able to identify,modify and effectively use the goods that have been given to us by mother nature.展开更多
Elastomeric polyurethanes were prepared from a reference polyurethane system modified with biobased polyols synthesized using rapeseed or palm oils.The reference material was modified by replacement of the commercial ...Elastomeric polyurethanes were prepared from a reference polyurethane system modified with biobased polyols synthesized using rapeseed or palm oils.The reference material was modified by replacement of the commercial polyol by 10%of biopolyols and also by addition of sisal fibers up to 5 wt%.The higher functionality of the biopolyols increased the crosslinking density of the networks and this was reflected by an increase in hardness and a decrease in water absorption.The effect of the sisal fibers mainly improved the mechanical and thermomechanical properties of the system with rapeseed oil because of good dispersion and strong fiber-matrix interaction.The system containing palm oil polyol corresponded to an initial formulation of high viscosity and,consequently,the resulting composites presented lower densities than the theoretically expected ones.These results are associated with fiber dispersion problems in the initial reactive mixture.展开更多
A direct enantio-,diastereo-,and chemo-selective high-performance liquid chromatographic method was developed for determining the content,enantiomeric purity,and related substances of the chiral antidepressant drug se...A direct enantio-,diastereo-,and chemo-selective high-performance liquid chromatographic method was developed for determining the content,enantiomeric purity,and related substances of the chiral antidepressant drug sertraline HCl in a single chromatographic run.The separation was achieved on a chiral stationary phase based on amylose tris(3-chloro-5-methylphenylcarbamate)under reversed-phase conditions.The method was optimized by evaluating the influence of the temperature and mobile phase composition on the retention and selectivity.The application of the single-run approach allowed to baseline resolve all investigated species in less than 15 min,without using buffers or tandem-coupled columns.The chromatographic method was validated according to the guidelines of the Official Medicines Control Laboratory and applied to control the content of sertraline HCl and related chiral substances in a generic antidepressant formulation.展开更多
Herein,an innovative glyphosate imprinted poly(hydroxyethyl) methacrylateN-methacroyl-(L)-phenylalanine methyl ester nanoparticles(MIP@NPs)based plasmonic nanosensor featured with high sensitivity and selectivity was ...Herein,an innovative glyphosate imprinted poly(hydroxyethyl) methacrylateN-methacroyl-(L)-phenylalanine methyl ester nanoparticles(MIP@NPs)based plasmonic nanosensor featured with high sensitivity and selectivity was constructed by using the molecular imprinting technique and used for real-time glyphosate detection.The characterization of nanoparticles was performed by the nano Zetasizer and scanning electron microscopy(SEM),while nanosensors were characterized by the Fourier transform infrared-attenuated total reflection(FTIR-ATR)and contact angle measurement.Control experiments were conducted to evaluate the imprinting efficiency on the signal response using a non-imprinted surface plasmon resonance(NIP SPR)nanosensor prepared without adding glyphosate pesticide into the polymerization mixture.The MIP@NPs integrated molecularly imprinted surface plasmon resonance(MIP SPR)nanosensor having synthetic molecular recognition elements yielded a novel biosensing platform for label-free detection and real-time monitoring of glyphosate pesticide.The MIP SPR nanosensor detected the target glyphosate molecule 4.950 times more selectively than the competitor molecule malathion while 3.918 times more selectively than the competitor molecule malaoxon.In addition,the imprinting efficiency factor was found to be 6.76,indicating that the molecular imprinting process was successful.In addition,the imprinting factor was found to be 6.76.Kinetic studies and adsorption characteristics of glycosate adsorption were carried out to assess adsorption dynamics.The linear concentration range for glyphosate detection was 0.001 ppm−10.000 ppm of pesticide,and the detection limit was found to be 0.120 ppb.Studies on the repeatability of the MIP SPR nanosensor revealed that even after five cycles,the signal response for glyphosate detection did not change significantly with relative standard deviation,RSD<1.5 value.The artificial urine selected as the real sample was spiked with glyphosate at a final concentration of 10.000 ppm to evaluate the matrix effect,and the glyphosate amount was reported.展开更多
1 Results The application of modified natural oils, nontoxic, biodegradable and renewable materials, for the modification and the synthesis of epoxy resins were presented. Firstly, the application of epoxidized vegeta...1 Results The application of modified natural oils, nontoxic, biodegradable and renewable materials, for the modification and the synthesis of epoxy resins were presented. Firstly, the application of epoxidized vegetable oils (soybean, rapeseed, linseed and sunflower):as reactive diluents for epoxy resins was proposed and studied[1-2]. Viscosity reducing ability of epoxidized oils was tested in the compositions with Bisphenol A based low-molecular-weight epoxy resins. The rheological behaviour of the mi...展开更多
基金supported by the Funding Project for Academic Human Resources Development in Institutions of Higher Learning under the Jurisdiction of Beijing Municipality (05005011200602)Foundation of Natural Science of Beijing Municipality (2082004)
文摘A series of lanthanide binuclear complexes, Ln2（L）6（H2O）4·2H2O（Ln=Sm（Ⅲ）, Gd（Ⅲ）, Er（Ⅲ）, Yb（Ⅲ）, HL=4-quinolinea-carboxylic acid, were synthesized by reactions of corresponding rare earth salts with 4-quinolineacarboxylic acid at room temperature and were characterized by elemental analysis, IR spectroscopy, and single-crystal X-ray diffraction.X-ray diffraction analyses showed that they exhibited the same binuclear architecture and crystallized in monoclinic system and P21/c space group.In four complexes, each metal center adopted nine-coordinated mode coordinated by nine O atoms from two H2O molecules and three carboxyls of three ligands, and HL showed three different coordination modes.The variable-temperature magnetic susceptibility showed that complex Gd2（L）6（H2O）4·2H2O performed very weak antiferromagnetic property at low temperature and exchange was almost paramagnetic at high temperature.Complexes Er2（L）6（H2O）4·2H2O and Yb2（L）6（H2O）4·2H2O performed dominating antiferromagnetic coupling.
文摘The aim of this work was to use cellulose nanocrystals that were obtained by hydrolysis in phosphoric acid solution and further modified with succinic anhydride in the microwave field for PLA reinforcement.A series of allbionanocomposites containing unmodified and surface modified cellulose nanocrystals with CNC content in the range of 1–3%_(w.t.) were obtained by melt blending and tested by XRD,SEM,DSC and DMA to investigate the effect of surface esterification of CNCs on the structure,morphology,dynamic mechanical properties of bionanocomposites,as well as phase transitions of PLA in the presence of cellulosic nanofiller.DMA investigations showed the highest increase of storage modulus by ca.7%(335 MPa at 25℃)in the glassy state of PLA for 2%_(w.t.)of unmodified CNC.Though,addition of 2%_(w.t.)of succinylated CNCs caused the highest increase of the onset of glass transition temperature(by 6.2℃)thus widening the temperature range of biocomposite application.The increase of glass transition temperature indicates the strongest interfacial interactions due to improved miscibility of surface modified nanocrystals and thus good dispersion of additive in PLA matrix providing high interface.
文摘Pomegranate flower plant, popularly known using for the treatment of various diseases, was not investigated as a source of dye for cytological studies using human blood cells. The importance of this study is to appear dyeing result of pomegranate flower extract on human blood cells. The natural dye source was pomegranate flower known as roselle and potassium aluminum sulfate （alum = KAISO4＇ 12H20） was used as mordant or metal salt. Distilled water was used as solvent. Fresh, clean and air-dried flowers were extracted with distilled water at 100℃ for 30 minutes and then filtered. One drop blood from a healthy 20-year woman was spread as a peripheral on to ten plates and dried at nearly 25℃. These slides were stained by soaking in pomegranate flower extract with/without alum （KA1SO4·12H2O） at 100℃ for 60 minutes. Slides were washed with distilled water, dried and done microscobic examination. The different blood cells dyed dark orange in alum mordant media at 100 ℃. As a result, pomegranate flower has the capacity to use dyeing human blood cells such as eosinophil, basophil and neutrophil.
基金financially supported by the Polish National Science Centre:Grant No.2012/07/D/ST5/02269supported by the Foundation for Polish Science (FNP)+1 种基金the financial support from Polish National Science Centre under Grant No.2015/17/D/ ST5/02571the financial support from Polish National Science Centre under Grant No.2016/23/N/ST5/02071
文摘Ordered titanium dioxide nanotubes （TiOaNTs） modified with indium tin oxide （ITO） films were obtained via magnetron sputtering, in which ITO plate was used as a target, onto the as-anodized titania support followed by the calcination process. The morphology of fabricated material with deposited oxide was investigated using scanning electron microscopy. Raman and UV-Vis spectroscopies were utilized to characterize crystalline phase and optical properties of prepared samples, whereas X-ray photoelectron spectroscopy allowed determining the binding energy of present elements. In the case of titanium, three various oxidation states were identified and also the presence of indium and tin was confirmed. The electrochemical test carried out when the sample was exposed to light allows for selection of the most photoactive material. The highest photocurrent was registered when only 5-nm ITO layer was sputtered, and it equals 256 and 133 μA cm^-2 for the electrode material immersed in 0.5 M KOH and K2SO4 electrolytes, respectively, that is accordingly 3.5 and 4.4 times higher than the one observed for pristine titania. Furthermore, ITO-modified titania exhibits excellent photostability upon prolonged illumination that is of key importance for possible application in light-driven processes.
文摘Succinite,Baltic amber,is one of the most appreciated fossil resins.Its beauty has fascinated people since prehistoric times.It is a substance,and also gemstone,whose uniqueness is due to its compelling,though still not fully understood,physicochemical nature.In this article,some facts about the physical and chemical properties of succinite in order to find an answer for questions about the unique properties of this resin,such as color,transparency,texture etc.,are discussed.These properties are among the factors that determine the choice of Baltic amber as a gemstone.Commonly known properties of succinite,but also some less obvious features,have been linked to the organic and inorganic chemical composition and structural factors,including the sophisticated supramolecular structure masterfully created by nature.Changes of the properties of succinite used as a jewelry stone are discussed as a reflection of changes in its physicochemical nature.In this light,some methods that can be used to identify succinite(i.e.,infrared spectroscopy and nuclear magnetic resonance spectroscopy)and their relevance to the classification of fossil resins are briefly discussed.This article highlights an important point:only by understanding the chemical and physical nature of the material we able to identify,modify and effectively use the goods that have been given to us by mother nature.
文摘Elastomeric polyurethanes were prepared from a reference polyurethane system modified with biobased polyols synthesized using rapeseed or palm oils.The reference material was modified by replacement of the commercial polyol by 10%of biopolyols and also by addition of sisal fibers up to 5 wt%.The higher functionality of the biopolyols increased the crosslinking density of the networks and this was reflected by an increase in hardness and a decrease in water absorption.The effect of the sisal fibers mainly improved the mechanical and thermomechanical properties of the system with rapeseed oil because of good dispersion and strong fiber-matrix interaction.The system containing palm oil polyol corresponded to an initial formulation of high viscosity and,consequently,the resulting composites presented lower densities than the theoretically expected ones.These results are associated with fiber dispersion problems in the initial reactive mixture.
文摘A direct enantio-,diastereo-,and chemo-selective high-performance liquid chromatographic method was developed for determining the content,enantiomeric purity,and related substances of the chiral antidepressant drug sertraline HCl in a single chromatographic run.The separation was achieved on a chiral stationary phase based on amylose tris(3-chloro-5-methylphenylcarbamate)under reversed-phase conditions.The method was optimized by evaluating the influence of the temperature and mobile phase composition on the retention and selectivity.The application of the single-run approach allowed to baseline resolve all investigated species in less than 15 min,without using buffers or tandem-coupled columns.The chromatographic method was validated according to the guidelines of the Official Medicines Control Laboratory and applied to control the content of sertraline HCl and related chiral substances in a generic antidepressant formulation.
文摘Herein,an innovative glyphosate imprinted poly(hydroxyethyl) methacrylateN-methacroyl-(L)-phenylalanine methyl ester nanoparticles(MIP@NPs)based plasmonic nanosensor featured with high sensitivity and selectivity was constructed by using the molecular imprinting technique and used for real-time glyphosate detection.The characterization of nanoparticles was performed by the nano Zetasizer and scanning electron microscopy(SEM),while nanosensors were characterized by the Fourier transform infrared-attenuated total reflection(FTIR-ATR)and contact angle measurement.Control experiments were conducted to evaluate the imprinting efficiency on the signal response using a non-imprinted surface plasmon resonance(NIP SPR)nanosensor prepared without adding glyphosate pesticide into the polymerization mixture.The MIP@NPs integrated molecularly imprinted surface plasmon resonance(MIP SPR)nanosensor having synthetic molecular recognition elements yielded a novel biosensing platform for label-free detection and real-time monitoring of glyphosate pesticide.The MIP SPR nanosensor detected the target glyphosate molecule 4.950 times more selectively than the competitor molecule malathion while 3.918 times more selectively than the competitor molecule malaoxon.In addition,the imprinting efficiency factor was found to be 6.76,indicating that the molecular imprinting process was successful.In addition,the imprinting factor was found to be 6.76.Kinetic studies and adsorption characteristics of glycosate adsorption were carried out to assess adsorption dynamics.The linear concentration range for glyphosate detection was 0.001 ppm−10.000 ppm of pesticide,and the detection limit was found to be 0.120 ppb.Studies on the repeatability of the MIP SPR nanosensor revealed that even after five cycles,the signal response for glyphosate detection did not change significantly with relative standard deviation,RSD<1.5 value.The artificial urine selected as the real sample was spiked with glyphosate at a final concentration of 10.000 ppm to evaluate the matrix effect,and the glyphosate amount was reported.
文摘1 Results The application of modified natural oils, nontoxic, biodegradable and renewable materials, for the modification and the synthesis of epoxy resins were presented. Firstly, the application of epoxidized vegetable oils (soybean, rapeseed, linseed and sunflower):as reactive diluents for epoxy resins was proposed and studied[1-2]. Viscosity reducing ability of epoxidized oils was tested in the compositions with Bisphenol A based low-molecular-weight epoxy resins. The rheological behaviour of the mi...
