Photoconductive and Antimicrobial Properties of Psidium guajava Leaf Extract Mediated Green Synthesized SnS2–CdO and SnS2–NiO Nanocomposites

2021 ◽  
pp. 2150034
Author(s):  
M. Suganya ◽  
R. Baskaran ◽  
V. S. Nagarethinam ◽  
A. R. Balu
Keyword(s):  
Leaf Extract ◽  
Aspergillus Terreus ◽  
Antimicrobial Properties ◽  
Psidium Guajava ◽  
X Ray Diffraction ◽  
Xps Spectra ◽  
Sem Image ◽  
Fungal Inhibition ◽  
Diffraction Peaks ◽  
Inhibition Property

This paper reports the photoconductive and antimicrobial properties of SnS2–CdO and SnS2-NiO nanocomposites green synthesized using Psidium guajava leaf extract. X-ray diffraction studies reveal that the SnS2–CdO nanocomposite exhibits hexagonal SnS2 and cubic CdO diffraction peaks; whereas the SnS2–NiO nanocomposite exhibits hexagonal SnS2 and cubic NiO diffraction peaks. SEM image of the bio-synthesized SnS2–CdO nanocomposite confirmed nanoneedles with grains being well distributed. Regular shaped grains with decreased sizes were observed for the SnS2–NiO nanocomposite. Nanosized grains were observed from the TEM images. The existence of elements Sn, S, Cd, O in SnS2–CdO nanocomposite; Sn, S, Ni, O in SnS2–NiO nanocomposite was confirmed from the EDX and XPS spectra. Increased photosensitivity value was realized for the SnS2–CdO nanocomposite. Both the composites showed good fungal inhibition property against Aspergillus terreus fungi not only by the physical, chemical and biological processes but also owing to phyto-constituents in the leaf extract.

Preparation of Silica Microspheres Coated by Nano-ZrO2

2014 ◽  
Vol 924 ◽  
pp. 36-40
Author(s):  
Chun Xiao Yue ◽  
Peng Ding ◽  
Yu Zhao ◽  
Li Yi Shi
Keyword(s):  
Sol Gel ◽  
Xrd Analysis ◽  
X Ray Diffraction ◽  
Silica Microspheres ◽  
Surface Layers ◽  
Sem Image ◽  
Sol Gel Process ◽  
Stretching Vibration ◽  
Ft Ir ◽  
Diffraction Peaks

Silica microspheres coated by nanoZrO2 were prepared by the sol-gel process using butoxidesolution (TBOZ) as precursor. The nanomicrospheres were formed via hydrolysis and condension reaction of metal alkoxides with the hydroxyl (-OH) of silica microspheres by form Zr-O-Si bonds. The samples were characterized by X-ray diffraction, FT-IR and SEM. Presence of the FT-IR bands with frequencies ranging from 800 to 900 cm-1 can be assigned to SiO vibration, and to ZrOSi stretching vibration. XRD analysis shows obviously the characteristic diffraction peaks of tetragonal (T-ZrO2) in the sample by heat-treatment at 400°C. The SEM image showed that the surface layers of silica microspheres were coated by nanoparticles.

scholarly journals Extraction of bioactive compounds from Psidium guajava leaves and its utilization in preparation of jellies

2020 ◽  
Author(s):  
Sampath Kumar N.S. ◽  
Norizah Mhd Sarbon ◽  
Sandeep Singh Rana ◽  
Anjani Devi Chintagunta ◽  
Prathibha S ◽  
...  
Keyword(s):  
Bioactive Compounds ◽  
Leaf Extract ◽  
Antimicrobial Properties ◽  
Psidium Guajava ◽  
Antimicrobial Activities ◽  
Lemon Juice ◽  
Vitamin B3 ◽  
The Public ◽  
Guava Leaf ◽  
Textural Analyses

Abstract Psidium guajava (guava) is predominantly grown in India and known for its medicinal properties in treating various diseases and disorders. The present work focuses on aqueous extraction of bioactive compounds from the guava leaf and its utilization in the formulation of jelly to improve the public health. The guava leaf extract has been used in the preparation of jelly with pectin (1.5 g), sugar (28 g) and lemon juice (2 mL). The prepared guava leaf extract jelly (GJ) and the control jelly (CJ, without extract) were subjected to proximate, nutritional and textural analyses besides determination of antioxidant and antimicrobial activities. GJ was found to contain carbohydrate (45.78 g/100 g), protein (3.0 g/100 g), vitamin C (6.15 mg/100 g), vitamin B3 (2.90 mg/100 g) and energy (120.6 kcal). Further, the texture analysis of CJ and GJ indicated that both the jellies showed similar properties emphasizing that the addition of guava leaf extract does not bring any change in the texture properties of jelly. GJ exhibited antimicrobial activity against various bacteria ranging from 11.4–13.6 mm. Similarly, GJ showed antioxidant activity of 42.38% against DPPH radical and 33.45% against hydroxyl radical. Mass spectroscopic analysis of aqueous extract confirmed the presence of esculin, quercetin, gallocatechin, 3-Sinapoylquinic acid, gallic acid, citric acid and ellagic acid which are responsible for antioxidant and antimicrobial properties.

Preparation of ZrO2-Silica Microspheres by Layer-by-Layer Self-Assemble Technique

2015 ◽  
Vol 723 ◽  
pp. 520-523
Author(s):  
Chun Xiao Yue ◽  
Peng Ding ◽  
Li Yi Shi
Keyword(s):  
Xrd Analysis ◽  
Layer By Layer ◽  
X Ray Diffraction ◽  
Silica Microspheres ◽  
Surface Layers ◽  
Sem Image ◽  
Stretching Vibration ◽  
Ft Ir ◽  
Diffraction Peaks ◽  
Ir Bands

The uniform nanoparticle multilayers micrometer-sized silica particle have been fabricated by consecutively assembling of surfactant C12H25SO4Na (SDS) and nanoparticles onto Silica microspheres and subsequently removing the surfactant by calcinations. The samples were characterized by X-ray diffraction, FT-IR,TG and SEM. Presence of the FT-IR bands with frequencies ranging from 800 to 900 cm-1 can be assigned to Si–O vibration, and to Zr–O–Si stretching vibration. XRD analysis showed obviously the characteristic diffraction peaks of tetragonal (T-ZrO2) and nanoscale of ZrO2. The SEM image showed that the surface layers of silica microspheres were coated by nanoparticles.

scholarly journals Extraction of bioactive compounds from Psidium guajava leaves and its utilization in preparation of jellies

AMB Express ◽  
2021 ◽  
Vol 11 (1) ◽  
Author(s):  
N. S. Sampath Kumar ◽  
Norizah Mhd Sarbon ◽  
Sandeep Singh Rana ◽  
Anjani Devi Chintagunta ◽  
S. Prathibha ◽  
...  
Keyword(s):  
Bioactive Compounds ◽  
Leaf Extract ◽  
Antimicrobial Properties ◽  
Psidium Guajava ◽  
Antimicrobial Activities ◽  
Lemon Juice ◽  
Vitamin B3 ◽  
The Public ◽  
Guava Leaf ◽  
Textural Analyses

AbstractPsidium guajava L. (guava) is predominantly grown throughout the world and known for its medicinal properties in treating various diseases and disorders. The present work focuses on aqueous extraction of bioactive compounds from the guava leaf and its utilization in the formulation of jelly to improve the public health. The guava leaf extract has been used in the preparation of jelly with pectin (1.5 g), sugar (28 g) and lemon juice (2 mL). The prepared guava leaf extract jelly (GJ) and the control jelly (CJ, without extract) were subjected to proximate, nutritional and textural analyses besides determination of antioxidant and antimicrobial activities. GJ was found to contain carbohydrate (45.78 g/100 g), protein (3.0 g/100 g), vitamin C (6.15 mg/100 g), vitamin B3 (2.90 mg/100 g) and energy (120.6 kcal). Further, the texture analysis of CJ and GJ indicated that both the jellies showed similar properties emphasizing that the addition of guava leaf extract does not bring any change in the texture properties of jelly. GJ exhibited antimicrobial activity against various bacteria ranging from 11.4 to 13.6 mm. Similarly, GJ showed antioxidant activity of 42.38% against DPPH radical and 33.45% against hydroxyl radical. Mass spectroscopic analysis of aqueous extract confirmed the presence of esculin, quercetin, gallocatechin, 3-sinapoylquinic acid, gallic acid, citric acid and ellagic acid which are responsible for antioxidant and antimicrobial properties.

Control of the phase composition of advanced calcium phosphates using an x-ray diffractometer with a curved position-sensitive detector

2020 ◽  
Vol 86 (6) ◽  
pp. 29-35
Author(s):  
V. P. Sirotinkin ◽  
O. V. Baranov ◽  
A. Yu. Fedotov ◽  
S. M. Barinov
Keyword(s):  
Phase Composition ◽  
Calcium Phosphates ◽  
Position Sensitive Detector ◽  
Sensitive Detector ◽  
X Ray Diffraction ◽  
X Ray ◽  
Impurity Phases ◽  
Position Sensitive ◽  
Diffraction Peaks ◽  
Diffraction Patterns

The results of studying the phase composition of advanced calcium phosphates Ca10(PO4)6(OH)2, β-Ca3(PO4)2, α-Ca3(PO4)2, CaHPO4 · 2H2O, Ca8(HPO4)2(PO4)4 · 5H2O using an x-ray diffractometer with a curved position-sensitive detector are presented. Optimal experimental conditions (angular positions of the x-ray tube and detector, size of the slits, exposure time) were determined with allowance for possible formation of the impurity phases during synthesis. The construction features of diffractometers with a position-sensitive detector affecting the profile characteristics of x-ray diffraction peaks are considered. The composition for calibration of the diffractometer (a mixture of sodium acetate and yttrium oxide) was determined. Theoretical x-ray diffraction patterns for corresponding calcium phosphates are constructed on the basis of the literature data. These x-ray diffraction patterns were used to determine the phase composition of the advanced calcium phosphates. The features of advanced calcium phosphates, which should be taken into account during the phase analysis, are indicated. The powder of high-temperature form of tricalcium phosphate strongly adsorbs water from the environment. A strong texture is observed on the x-ray diffraction spectra of dicalcium phosphate dihydrate. A rather specific x-ray diffraction pattern of octacalcium phosphate pentahydrate revealed the only one strong peak at small angles. In all cases, significant deviations are observed for the recorded angular positions and relative intensity of the diffraction peaks. The results of the study of experimentally obtained mixtures of calcium phosphate are presented. It is shown that the graphic comparison of experimental x-ray diffraction spectra and pre-recorded spectra of the reference calcium phosphates and possible impurity phases is the most effective method. In this case, there is no need for calibration. When using this method, the total time for analysis of one sample is no more than 10 min.

scholarly journals Optical, XPS and XRD Studies of Semiconducting Copper Sulfide Layers on a Polyamide Film

2009 ◽  
Vol 2009 ◽  
pp. 1-8 ◽  
Author(s):  
Valentina Krylova ◽  
Mindaugas Andrulevičius
Keyword(s):  
Photoelectron Spectroscopy ◽  
Copper Sulfide ◽  
Diffusion Method ◽  
X Ray Diffraction ◽  
Xps Spectra ◽  
X Ray ◽  
Xrd Studies ◽  
Polyamide Film ◽  
Indirect Band Gap ◽  
Xrd Method

Copper sulfide layers were formed on polyamide PA 6 surface using the sorption-diffusion method. Polymer samples were immersed for 4 and 5 h in 0.15 mol⋅  solutions and acidified with HCl (0.1 mol⋅) at . After washing and drying, the samples were treated with Cu(I) salt solution. The samples were studied by UV/VIS, X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) methods. All methods confirmed that on the surface of the polyamide film a layer of copper sulfide was formed. The copper sulfide layers are indirect band-gap semiconductors. The values of are 1.25 and 1.3 eV for 4 h and 5 h sulfured PA 6 respectively. Copper XPS spectra analyses showed Cu(I) bonds only in deeper layers of the formed film, while in sulfur XPS S 2p spectra dominating sulfide bonds were found after cleaning the surface with ions. It has been established by the XRD method that, beside , the layer contains as well. For PA 6 initially sulfured 4 h, grain size forchalcocite, , was  nm and fordjurleite, , it was 54.17 nm. The sheet resistance of the obtained layer varies from 6300 to 102 .

Comparative Studies of Ultra Low-κ Porous Silica Films with 2-D Hexagonal and Disordered Pore Structures

2004 ◽  
Vol 812 ◽  
Author(s):  
Nobutoshi Fujii ◽  
Kazuhiro Yamada ◽  
Yoshiaki Oku ◽  
Nobuhiro Hata ◽  
Yutaka Seino ◽  
...  
Keyword(s):  
Pore Structure ◽  
Nonionic Surfactants ◽  
Porous Silica ◽  
Silica Film ◽  
X Ray Diffraction ◽  
Silica Films ◽  
X Ray ◽  
X Ray Scattering ◽  
Porous Silica Film ◽  
Diffraction Peaks

AbstractPeriodic 2-dimensional (2-D) hexagonal and the disordered pore structure silica films have been developed using nonionic surfactants as the templates. The pore structure was controlled by the static electrical interaction between the micelle of the surfactant and the silica oligomer. No X-ray diffraction peaks were observed for the disordered mesoporous silica films, while the pore diameters of 2.0-4.0 nm could be measured by small angle X-ray scattering spectroscopy. By comparing the properties of the 2-D hexagonal and the disordered porous silica films which have the same porosity, it is found that the disordered porous silica film has advantages in terms of the dielectric constant and Young's modulus as well as the hardness. The disordered porous silica film is more suitable for the interlayer dielectrics for ULSI.

The crystal chemistry of the uranyl carbonate mineral grimselite, (K, Na)3Na[(UO2)(CO3)3](H2O), from Jáchymov, Czech Republic

2012 ◽  
Vol 76 (3) ◽  
pp. 443-453 ◽  
Author(s):  
J. Plášil ◽  
K. Fejfarová ◽  
R. Skála ◽  
R. Škoda ◽  
N. Meisser ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Czech Republic ◽  
Structure Refinement ◽  
Unit Cell ◽  
Carbonate Mineral ◽  
X Ray Diffraction ◽  
The Czech Republic ◽  
Cell Parameters ◽  
Uranyl Carbonate ◽  
Diffraction Peaks

AbstractTwo crystals of the uranyl carbonate mineral grimselite, ideally K3Na[(UO2)(CO3)3](H2O), from Jáchymov in the Czech Republic were studied by single-crystal X-ray diffraction and electron-probe microanalysis. One crystal has considerably more Na than the ideal chemical composition due to substitution of Na into KO8 polyhedra; the composition of the other crystal is nearer to ideal, and similar to synthetic grimselite. The presence of Na atoms in KO8 polyhedra, which are located in channels in the crystal structure, reduces their volume, and as a result the unit-cell volume also decreases. Structure refinement shows that the formula for the sample with the anomalously high Na content is (K2.43Na0.57)Σ3.00Na[(UO2)(CO3)3](H2O). The unit-cell parameters, refined in space group P2c, are a = 9.2507(1), c = 8.1788(1) Å, V = 606.14(3) Å3 and Z = 2. The crystal structure was refined to R1 = 0.0082 and wR1 = 0.0185 with a GOF = 1.33, based on 626 observed diffraction peaks [Iobs>3σ(I)].

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