ZnSe∶Mn nanocrystals were grown by chemical vapour transport method using the matrix of SiO2 aerogels. The cubic structure of the nanocrystals was confirmed by powder X-ray diffraction (XRD) and electron diffraction ...ZnSe∶Mn nanocrystals were grown by chemical vapour transport method using the matrix of SiO2 aerogels. The cubic structure of the nanocrystals was confirmed by powder X-ray diffraction (XRD) and electron diffraction (ED) studies. The size of the crystals was observed using transmission electron microscope (TEM). The oxidation state of Mn in ZnSe nanocrystal was found using electron spin resonance (ESR) spectrum. The room temperature luminescence measurements show the peaks corresponding to both bandgap of the material and Mn in ZnSe.展开更多
Single crystals of Glycine Zinc Chloride (GZC) were grown from aqueous solution by slow evaporation technique. Single crystal X-ray diffraction analysis reveals that the crystal belongs to orthorhombic system with the...Single crystals of Glycine Zinc Chloride (GZC) were grown from aqueous solution by slow evaporation technique. Single crystal X-ray diffraction analysis reveals that the crystal belongs to orthorhombic system with the space group Pna21.The optical transmission study reveals the transparency of the crystal in the entire visible region and the cut off wavelength has been found to be 230 nm. The optical band gap is found to be 3.40eV. The transmittance of GZC crystal has been used to calculate the refractive index (n), the extinction coefficient (K) and the real er and imaginary ei components of the dielectric constant. Mechanical studies were carried out on the as grown crystal. Dielectric constant and dielectric loss measurements were carried out at different temperatures and frequencies. Photoconductivity measurements carried out on the grown crystal reveal the negative photoconducting nature.展开更多
Nonlinear optical single crystals of L-phenylalanine-4-nitrophenol have been grown by the slow evaporation method. The grown crystal was subjected to the single crystal X-ray diffraction analysis, to confirm that it b...Nonlinear optical single crystals of L-phenylalanine-4-nitrophenol have been grown by the slow evaporation method. The grown crystal was subjected to the single crystal X-ray diffraction analysis, to confirm that it belongs to the monoclinic crystal structure, with space group P21. The optical transmission study reveals the transparency of the crystal in the entire visible region and the cut off wave length has been found to be 320 nm. The optical band gap is found to be 3.87 eV. The transmittance of the L-phenylalanine-4-nitrophenol crystal has been used to calculate the refractive index (n), the extinction coefficient (K) and the real (εr) and imaginary (εi) components of the dielectric constant. The mechanical behaviour of the grown crystals was studied using Vicker’s microhardness tester. The dielectric constant and dielectric loss of L-phenylalanine-4-nitrophenol are measured in the frequency range of 50 Hz to 5 MHz at different temperatures. The photoconductivity study confirms the negative photoconductive nature of the sample.展开更多
Crystals of DL-threonium trichloroacetate (DLTTCA) was synthesized from an aqueous solution by slow evaporation technique. The grown crystals were characterized by X-ray diffraction, Fourier transform infrared spectro...Crystals of DL-threonium trichloroacetate (DLTTCA) was synthesized from an aqueous solution by slow evaporation technique. The grown crystals were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, UV-Vis-NIR and SHG measurements. Vibrational structure of the crystal was elucidated from FTIR analysis and the hydrogen bond interactions were discussed in detail. The ultraviolet transparent cutoff falls at 212 nm. Thermal stability of the compound was also studied. The powder SHG efficiency of the compound was measured as 0.62 times to that of KDP.展开更多
Non-linear optical materials find wide range of applications in the fields of opto-electronics, fiber optic communication, computer memory devices etc. Tris-Glycine Zinc Chloride (TGZC) is one of the NLO materials exh...Non-linear optical materials find wide range of applications in the fields of opto-electronics, fiber optic communication, computer memory devices etc. Tris-Glycine Zinc Chloride (TGZC) is one of the NLO materials exhibiting more efficiency. In the present study Tris-Glycine Zinc Chloride were grown is single crystal form using slow evaporation technique. Single crystal X-ray diffraction analysis reveals that the crystal belongs to orthorhombic system with the space group Pbn21. The optical absorption studies show that the crystal is transparent in the entire visible region with a cut off wavelength of 250 nm. The optical band gap is found to be 4.60 eV. The dependence of extinction coefficient (K) and refractive index (n) on the wavelength has also been reported. Force constants (k) were calculated using FTIR spectral analysis which shows higher values of k for COO and C=O stretching vibrations. The dielectric studies show that the dielectric constant and dielectric loss decrease exponentially with frequency at different temperatures (35℃, 55℃, 75℃ and 95℃).展开更多
This paper summarizes the synthesis, growth and the effect of the position of the substituent in the thienyl ring and also the properties of the grown chalcone crystals, 2-CTP and 3-CTP. The formation of compound is c...This paper summarizes the synthesis, growth and the effect of the position of the substituent in the thienyl ring and also the properties of the grown chalcone crystals, 2-CTP and 3-CTP. The formation of compound is confirmed by the re- corded H1NMR spectra. A FT-IR spectrum confirms the presence of all functional groups in both of the crystals. Single crystal XRD reports that even though these two compounds crystallize in monoclinic crystal system, 2-CTP has centro- symmetric P21/c space group and 3-CTP has non-centrosymmetric space group P21. Thermal properties of grown crys- tals analyzed by TG/DTA study explain that the 3-CTP compound is slightly more stable than 2-CTP. The transparency of these isomers in the vis-IR region has been studied. Second and third order nonlinear optical properties of 3-CTP and 2-CTP crystals have been investigated by powder SHG and Z-scan technique respectively.展开更多
The current study investigated a triad,which comprises of adipose tissue derived stem cells isolated from infrapatellar fat pad and gelatin/polyvinyl alcohol(PVA)-based matrix with exclusive ascorbic acid signalling.T...The current study investigated a triad,which comprises of adipose tissue derived stem cells isolated from infrapatellar fat pad and gelatin/polyvinyl alcohol(PVA)-based matrix with exclusive ascorbic acid signalling.Though,the bio-mechanical properties of the gelatin–PVA blended scaffolds in wet condition are equivalent to the ECM of soft tissues in general,in this study,the triad was tested as a model for neural tissue engineering.Apart from being cytocompatible and biocompatible,the porosity of the scaffold has been designed in such a manner that it facilitates the cell signalling and enables the exchange of nutrients and gases.The highly proliferative stem cells from Passage 2 were characterized using both,mesenchymal and embryonic stem cell markers.As an initial exploration the mesenchymal stem cells at Passage 4 were exposed to ascorbic acid and basic fibroblast growth factor signalling for neuronal differentiation in 2D environment independently.The MSCs successfully differentiated and acquired neuron specific markers related to cytoskeleton and synapses.Subsequently,three phases of experiments have been conducted on the 3D gelatin/PVA matrix to prove their efficacy,the growth of stem cells,growth of differentiated neurons and the in situ growth and differentiation of MSCs.The scaffold was conducive and directed MSCs to neuronal lineage under specific signalling.Overall,this organotypic model triad could open a new avenue in the field of soft tissue engineering as a simple and effective tissue construct.展开更多
Synthesis of copper zinc tin sulphide（Cu_2ZnSnS_4/ with nanoplate morphology was achieved through colloidal method using oleic acid as capping agent and solvent with 1-octadecene（1-ODE） at 240°C.X-ray diffract...Synthesis of copper zinc tin sulphide（Cu_2ZnSnS_4/ with nanoplate morphology was achieved through colloidal method using oleic acid as capping agent and solvent with 1-octadecene（1-ODE） at 240°C.X-ray diffraction（XRD） analysis shows that the synthesized nanoplates possessed pure kesterite phase.SEM analysis clearly shows the formation of nanoplates having the size of about 50–100 nm.Electron spin resonance（ESR） spectrum analysis of the prepared nanoplates shows that the valence state of copper（II） which indicates the strong coupling with other metal ions.Thermo gravimetric/differential thermal analysis（TG/DTA） analysis shows the weight loss of sample at 450°C predicting the loss of capping ligands on the surface of the nanoparticles.The possible mechanism for the conversion of nanoplate-like structures during synthesis was discussed.The results are discussed in detail.展开更多
Using the conventional solid-state reaction method,0.5 wt.%of MnO_(2)^(-),NiO^(-),Cr_(2)O_(3)-,Fe_(2)O_(3)-and Co_(2)O_(3)-added 0.94Na_(0.5)-Bi_(0.5)TiO_(3)(NBT)–0.06BaTiO_(3)(BT)ceramics were prepared.The perovskit...Using the conventional solid-state reaction method,0.5 wt.%of MnO_(2)^(-),NiO^(-),Cr_(2)O_(3)-,Fe_(2)O_(3)-and Co_(2)O_(3)-added 0.94Na_(0.5)-Bi_(0.5)TiO_(3)(NBT)–0.06BaTiO_(3)(BT)ceramics were prepared.The perovskite nature of the prepared ceramics was analyzed by powder XRD and the surface morphology was studied by means of SEM.The dielectric analysis was carried out from room temperature to 350℃ at various frequencies and the diffusive transition at the dielectric maxima confirmed the relaxor nature of the ceramics.Creation of oxygen vacancies by the possible substitution of ferromagnetic impurities decreased the dielectric constant and piezoelectric constant(d_(33)).The co-existence of ferromagnetism and the ferroelectricity was observed in the Mn,Ni,Co and Cr-added NBT–BT ceramics.The magnetic force microscopy(MFM)analysis was carried out to study the ferromagnetic domains in the prepared ceramic.展开更多
文摘ZnSe∶Mn nanocrystals were grown by chemical vapour transport method using the matrix of SiO2 aerogels. The cubic structure of the nanocrystals was confirmed by powder X-ray diffraction (XRD) and electron diffraction (ED) studies. The size of the crystals was observed using transmission electron microscope (TEM). The oxidation state of Mn in ZnSe nanocrystal was found using electron spin resonance (ESR) spectrum. The room temperature luminescence measurements show the peaks corresponding to both bandgap of the material and Mn in ZnSe.
文摘Single crystals of Glycine Zinc Chloride (GZC) were grown from aqueous solution by slow evaporation technique. Single crystal X-ray diffraction analysis reveals that the crystal belongs to orthorhombic system with the space group Pna21.The optical transmission study reveals the transparency of the crystal in the entire visible region and the cut off wavelength has been found to be 230 nm. The optical band gap is found to be 3.40eV. The transmittance of GZC crystal has been used to calculate the refractive index (n), the extinction coefficient (K) and the real er and imaginary ei components of the dielectric constant. Mechanical studies were carried out on the as grown crystal. Dielectric constant and dielectric loss measurements were carried out at different temperatures and frequencies. Photoconductivity measurements carried out on the grown crystal reveal the negative photoconducting nature.
文摘Nonlinear optical single crystals of L-phenylalanine-4-nitrophenol have been grown by the slow evaporation method. The grown crystal was subjected to the single crystal X-ray diffraction analysis, to confirm that it belongs to the monoclinic crystal structure, with space group P21. The optical transmission study reveals the transparency of the crystal in the entire visible region and the cut off wave length has been found to be 320 nm. The optical band gap is found to be 3.87 eV. The transmittance of the L-phenylalanine-4-nitrophenol crystal has been used to calculate the refractive index (n), the extinction coefficient (K) and the real (εr) and imaginary (εi) components of the dielectric constant. The mechanical behaviour of the grown crystals was studied using Vicker’s microhardness tester. The dielectric constant and dielectric loss of L-phenylalanine-4-nitrophenol are measured in the frequency range of 50 Hz to 5 MHz at different temperatures. The photoconductivity study confirms the negative photoconductive nature of the sample.
文摘Crystals of DL-threonium trichloroacetate (DLTTCA) was synthesized from an aqueous solution by slow evaporation technique. The grown crystals were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, UV-Vis-NIR and SHG measurements. Vibrational structure of the crystal was elucidated from FTIR analysis and the hydrogen bond interactions were discussed in detail. The ultraviolet transparent cutoff falls at 212 nm. Thermal stability of the compound was also studied. The powder SHG efficiency of the compound was measured as 0.62 times to that of KDP.
文摘Non-linear optical materials find wide range of applications in the fields of opto-electronics, fiber optic communication, computer memory devices etc. Tris-Glycine Zinc Chloride (TGZC) is one of the NLO materials exhibiting more efficiency. In the present study Tris-Glycine Zinc Chloride were grown is single crystal form using slow evaporation technique. Single crystal X-ray diffraction analysis reveals that the crystal belongs to orthorhombic system with the space group Pbn21. The optical absorption studies show that the crystal is transparent in the entire visible region with a cut off wavelength of 250 nm. The optical band gap is found to be 4.60 eV. The dependence of extinction coefficient (K) and refractive index (n) on the wavelength has also been reported. Force constants (k) were calculated using FTIR spectral analysis which shows higher values of k for COO and C=O stretching vibrations. The dielectric studies show that the dielectric constant and dielectric loss decrease exponentially with frequency at different temperatures (35℃, 55℃, 75℃ and 95℃).
文摘This paper summarizes the synthesis, growth and the effect of the position of the substituent in the thienyl ring and also the properties of the grown chalcone crystals, 2-CTP and 3-CTP. The formation of compound is confirmed by the re- corded H1NMR spectra. A FT-IR spectrum confirms the presence of all functional groups in both of the crystals. Single crystal XRD reports that even though these two compounds crystallize in monoclinic crystal system, 2-CTP has centro- symmetric P21/c space group and 3-CTP has non-centrosymmetric space group P21. Thermal properties of grown crys- tals analyzed by TG/DTA study explain that the 3-CTP compound is slightly more stable than 2-CTP. The transparency of these isomers in the vis-IR region has been studied. Second and third order nonlinear optical properties of 3-CTP and 2-CTP crystals have been investigated by powder SHG and Z-scan technique respectively.
基金National Foundation for Liver Research(NFLR)for financially supporting the cell-based work in this project.CIBER-BBN is an initiative funded by the VI National R&D&I Plan 2008–2011,Iniciativa Ingenio 2010,Consolider Program.CIBER actions are financed by the Instituto de Salud CarlosⅢwith assistance from the European Regional Development Fundthe University Grants Commission,India for the award of the Basic Scientific Research(UGC-BSR)Faculty Fellowship[No.F.4-5(11)2019(BSR)].
文摘The current study investigated a triad,which comprises of adipose tissue derived stem cells isolated from infrapatellar fat pad and gelatin/polyvinyl alcohol(PVA)-based matrix with exclusive ascorbic acid signalling.Though,the bio-mechanical properties of the gelatin–PVA blended scaffolds in wet condition are equivalent to the ECM of soft tissues in general,in this study,the triad was tested as a model for neural tissue engineering.Apart from being cytocompatible and biocompatible,the porosity of the scaffold has been designed in such a manner that it facilitates the cell signalling and enables the exchange of nutrients and gases.The highly proliferative stem cells from Passage 2 were characterized using both,mesenchymal and embryonic stem cell markers.As an initial exploration the mesenchymal stem cells at Passage 4 were exposed to ascorbic acid and basic fibroblast growth factor signalling for neuronal differentiation in 2D environment independently.The MSCs successfully differentiated and acquired neuron specific markers related to cytoskeleton and synapses.Subsequently,three phases of experiments have been conducted on the 3D gelatin/PVA matrix to prove their efficacy,the growth of stem cells,growth of differentiated neurons and the in situ growth and differentiation of MSCs.The scaffold was conducive and directed MSCs to neuronal lineage under specific signalling.Overall,this organotypic model triad could open a new avenue in the field of soft tissue engineering as a simple and effective tissue construct.
基金Project supported by the Department of Science and Technology,Govt of India(No.DST/TMC/SERI/FR/90)
文摘Synthesis of copper zinc tin sulphide（Cu_2ZnSnS_4/ with nanoplate morphology was achieved through colloidal method using oleic acid as capping agent and solvent with 1-octadecene（1-ODE） at 240°C.X-ray diffraction（XRD） analysis shows that the synthesized nanoplates possessed pure kesterite phase.SEM analysis clearly shows the formation of nanoplates having the size of about 50–100 nm.Electron spin resonance（ESR） spectrum analysis of the prepared nanoplates shows that the valence state of copper（II） which indicates the strong coupling with other metal ions.Thermo gravimetric/differential thermal analysis（TG/DTA） analysis shows the weight loss of sample at 450°C predicting the loss of capping ligands on the surface of the nanoparticles.The possible mechanism for the conversion of nanoplate-like structures during synthesis was discussed.The results are discussed in detail.
文摘Using the conventional solid-state reaction method,0.5 wt.%of MnO_(2)^(-),NiO^(-),Cr_(2)O_(3)-,Fe_(2)O_(3)-and Co_(2)O_(3)-added 0.94Na_(0.5)-Bi_(0.5)TiO_(3)(NBT)–0.06BaTiO_(3)(BT)ceramics were prepared.The perovskite nature of the prepared ceramics was analyzed by powder XRD and the surface morphology was studied by means of SEM.The dielectric analysis was carried out from room temperature to 350℃ at various frequencies and the diffusive transition at the dielectric maxima confirmed the relaxor nature of the ceramics.Creation of oxygen vacancies by the possible substitution of ferromagnetic impurities decreased the dielectric constant and piezoelectric constant(d_(33)).The co-existence of ferromagnetism and the ferroelectricity was observed in the Mn,Ni,Co and Cr-added NBT–BT ceramics.The magnetic force microscopy(MFM)analysis was carried out to study the ferromagnetic domains in the prepared ceramic.
