53 research outputs found
Cadmium Sulfide Nanoparticles Decorated with Au Quantum Dots as Ultrasensitive Photoelectrochemical Sensor for Selective Detection of Copper(II) Ions
Anomalous
ingestion of copper has significant adverse effects and
shows acute toxicity in living organisms. Recently, photoelectrochemical
(PEC) method has attracted much attention as a platform for a Cu<sup>2+</sup> ion sensor because of its high sensitivity, selectivity,
low-cost, and accurate selection compared to other conventional methods.
In this work, stepwise hydrothermal and <i>in situ</i> chemical
approaches for synthesizing cadmium sulfide nanoparticles (CdS NPs)
for decorating gold quantum dots (Au QDs) are presented, along with
notable PEC performance. The amount of Au QDs loaded on the CdS NPs
had a significant influence on the PEC performance. CdS NPs-Au QDs-2
with 1.0 mmol % Au QDs demonstrated an exceptional photocurrent density
of 350.6 ΞΌA cm<sup>β2</sup>, which was 3.7-, 2.2-, and
2.0-fold higher than those of CdS NPs, CdS NPs-Au QDs-1 (0.75 mmol
%), and CdS NPs-Au QDs-3 (1.25 mmol %), respectively. Femtosecond
transient absorption dynamics of the ground state recovery showed
a buildup time of 243 fs for Au and 268 fs for CdS, which were assigned
to cooling of the photoexcited electrons. For CdS NPs-Au QDs, the
transient spectrum was dominated by a signal from CdS with no contribution
from Au. The fast buildup dynamic was absent in CdS-Au, indicating
a rapid transfer of the photoexcited electrons from CdS to Au before
cooling down. Unquestionably, the CdS NPs-Au QDs-2 photoelectrode
response upon Cu<sup>2+</sup> detection showed the lowest limit of
detection of 6.73 nM in a linear range of 0.5β120 nM. The selectivity
of CdS NPs-Au QDs-2 toward Cu<sup>2+</sup> ions in lake and tap water
was also studied, which suggested that CdS NPs-Au QDs-2 is promising
as a photoactive material for PEC-based environmental monitoring and
analysis
Bioinspired Nanomaterials
Biological synthesis employing microorganisms, fungi or plants is an alternative method to produce nanoparticles in low-cost and eco-friendly ways. The book covers the synthesis of metal nanoparticles, metal oxide nanostructures and nanocomposite materials, as well as the stability and characterization of bioinspired nanomaterials. Applications include optical and electrochemical sensors, packaging, SERS and drug delivery processes.ΠΡΠΏΠΎΠ»ΡΠ·ΡΠ΅ΠΌΡΠ΅ ΠΏΡΠΎΠ³ΡΠ°ΠΌΠΌΡ Adobe AcrobatΠΠΈΠΎΠ»ΠΎΠ³ΠΈΡΠ΅ΡΠΊΠΈΠΉ ΡΠΈΠ½ΡΠ΅Π· Ρ ΠΈΡΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°Π½ΠΈΠ΅ΠΌ ΠΌΠΈΠΊΡΠΎΠΎΡΠ³Π°Π½ΠΈΠ·ΠΌΠΎΠ², Π³ΡΠΈΠ±ΠΎΠ² ΠΈΠ»ΠΈ ΡΠ°ΡΡΠ΅Π½ΠΈΠΉ ΡΠ²Π»ΡΠ΅ΡΡΡ Π°Π»ΡΡΠ΅ΡΠ½Π°ΡΠΈΠ²Π½ΡΠΌ ΠΌΠ΅ΡΠΎΠ΄ΠΎΠΌ ΠΏΠΎΠ»ΡΡΠ΅Π½ΠΈΡ Π½Π°Π½ΠΎΡΠ°ΡΡΠΈΡ Π½Π΅Π΄ΠΎΡΠΎΠ³ΠΈΠΌΠΈ ΠΈ ΡΠΊΠΎΠ»ΠΎΠ³ΠΈΡΠ΅ΡΠΊΠΈ ΡΠΈΡΡΡΠΌΠΈ ΡΠΏΠΎΡΠΎΠ±Π°ΠΌΠΈ. ΠΠ½ΠΈΠ³Π° ΠΏΠΎΡΠ²ΡΡΠ΅Π½Π° ΡΠΈΠ½ΡΠ΅Π·Ρ Π½Π°Π½ΠΎΡΠ°ΡΡΠΈΡ ΠΌΠ΅ΡΠ°Π»Π»ΠΎΠ², Π½Π°Π½ΠΎΡΡΡΡΠΊΡΡΡ ΠΈΠ· ΠΎΠΊΡΠΈΠ΄ΠΎΠ² ΠΌΠ΅ΡΠ°Π»Π»ΠΎΠ² ΠΈ Π½Π°Π½ΠΎΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡΠ½ΡΡ
ΠΌΠ°ΡΠ΅ΡΠΈΠ°Π»ΠΎΠ², Π° ΡΠ°ΠΊΠΆΠ΅ ΡΡΠ°Π±ΠΈΠ»ΡΠ½ΠΎΡΡΠΈ ΠΈ Ρ
Π°ΡΠ°ΠΊΡΠ΅ΡΠΈΡΡΠΈΠΊΠ°ΠΌ Π½Π°Π½ΠΎΠΌΠ°ΡΠ΅ΡΠΈΠ°Π»ΠΎΠ², Π²Π΄ΠΎΡ
Π½ΠΎΠ²Π»Π΅Π½Π½ΡΡ
Π±ΠΈΠΎΠΈΠ½ΡΠΏΠΈΡΠΈΡΠΎΠ²Π°Π½ΠΈΠ΅ΠΌ. ΠΠ±Π»Π°ΡΡΠΈ ΠΏΡΠΈΠΌΠ΅Π½Π΅Π½ΠΈΡ Π²ΠΊΠ»ΡΡΠ°ΡΡ ΠΎΠΏΡΠΈΡΠ΅ΡΠΊΠΈΠ΅ ΠΈ ΡΠ»Π΅ΠΊΡΡΠΎΡ
ΠΈΠΌΠΈΡΠ΅ΡΠΊΠΈΠ΅ Π΄Π°ΡΡΠΈΠΊΠΈ, ΡΠΏΠ°ΠΊΠΎΠ²ΠΊΡ, SERS ΠΈ ΠΏΡΠΎΡΠ΅ΡΡΡ Π΄ΠΎΡΡΠ°Π²ΠΊΠΈ Π»Π΅ΠΊΠ°ΡΡΡΠ²
Bioinspired Nanomaterials for Energy and Environmental Applications
Π ΠΊΠ½ΠΈΠ³Π΅ ΠΏΡΠ΅Π΄ΡΡΠ°Π²Π»Π΅Π½Ρ ΠΏΠΎΡΠ»Π΅Π΄Π½ΠΈΠ΅ Π΄ΠΎΡΡΠΈΠΆΠ΅Π½ΠΈΡ Π² ΠΎΠ±Π»Π°ΡΡΠΈ ΡΠΈΠ½ΡΠ΅Π·Π° Π½Π°Π½ΠΎΠΌΠ°ΡΠ΅ΡΠΈΠ°Π»ΠΎΠ² Ρ Π±ΠΈΠΎΠΈΠ½ΡΠΏΠΈΡΠΈΡΠΎΠ²Π°Π½ΠΈΠ΅ΠΌ ΠΈ ΠΈΡ
ΠΏΡΠΈΠΌΠ΅Π½Π΅Π½ΠΈΡ Π² ΡΠ°ΠΊΠΈΡ
ΠΎΠ±Π»Π°ΡΡΡΡ
, ΠΊΠ°ΠΊ ΡΠΎΡΠΎΠΊΠ°ΡΠ°Π»ΠΈΠ·, ΡΠ»Π΅ΠΊΡΡΠΎΠΊΠ°ΡΠ°Π»ΠΈΠ· ΠΈ ΡΠΎΡΠΎΡΠ»Π΅ΠΊΡΡΠΎΠΊΠ°ΡΠ°Π»ΠΈΠ·Π°ΡΠΎΡ, ΡΡΠΏΠ΅ΡΠΊΠΎΠ½Π΄Π΅Π½ΡΠ°ΡΠΎΡΡ ΠΈ ΡΠΎΠ»Π½Π΅ΡΠ½ΡΠ΅ ΡΠ»Π΅ΠΌΠ΅Π½ΡΡ. ΠΠΎΠ½ΠΊΡΠ΅ΡΠ½ΡΠ΅ ΡΠ΅ΠΌΡ Π²ΠΊΠ»ΡΡΠ°ΡΡ ΡΠΎΡΠΎΠΊΠ°ΡΠ°Π»ΠΈΡΠΈΡΠ΅ΡΠΊΡΡ Π΄Π΅Π·ΠΈΠ½ΡΠ΅ΠΊΡΠΈΡ, ΡΠ°Π·Π»ΠΎΠΆΠ΅Π½ΠΈΠ΅ ΡΠΎΠΊΡΠΈΡΠ½ΡΡ
Ρ
ΠΈΠΌΠΈΡΠ΅ΡΠΊΠΈΡ
Π²Π΅ΡΠ΅ΡΡΠ², ΠΏΡΠ΅ΠΎΠ±ΡΠ°Π·ΠΎΠ²Π°Π½ΠΈΠ΅ ΡΠ½Π΅ΡΠ³ΠΈΠΈ ΠΈ Π½Π°ΠΊΠΎΠΏΠ»Π΅Π½ΠΈΠ΅ ΡΠ½Π΅ΡΠ³ΠΈΠΈ.ΠΡΠΏΠΎΠ»ΡΠ·ΡΠ΅ΠΌΡΠ΅ ΠΏΡΠΎΠ³ΡΠ°ΠΌΠΌΡ Adobe AcrobatThe book presents recent advances in the synthesis of bioinspired nanomaterials and their applications in areas such as photocatalysis, electrocatalysis and photoelectrocatalysis, supercapacitors and solar cells. Specific topics include photocatalytic disinfection, degradation of toxic chemicals, energy conversion and energy storage
Antioxidant and free radical scavenging activities of common wild greens from Tiruvallur District of Tamil Nadu, India
156-163The antioxidant and radical scavenging activities of common wild greens
used by the village people in Tiruvallur District, Tamil Nadu were evaluated.
Among the plants studied, the methanol extract of Euphorbia hirta Linn. was
found to be rich in polyphenol content and had a low IC50 value for
DPPH (78.33 Β΅g) and hydroxyl radical scavenging (662.62 Β΅g). It showed high
antioxidant activity. The methanol extract of Senna auriculata (Linn.) Roxb. syn. Cassia auriculata Linn. flowers
and Eclipta prostrata Linn., leaves
were also effective. The efficacies
of the other plants were in the following order: Cardiospermum helicacabum Linn.var. luridum Blume > Boerhavia
diffusa Linn. > Centella asiatica (Linn.) Urban > Cissus quadrangularis Linn. > Celosia argentea Linn. > Marsilea quadrifolia Linn. > Pisonia grandis R. Br. syn. P. alba Span. > Solanum trilobatum Linn.
These plants have been traditionally used by villagers without any noticeable
adverse effects. The present study has indicated that the isolation of some
specific compounds responsible for these activities might help in several
aspects of food chemistry
Additions To the Grass Flora of Tamil Nadu
Volume: 102Start Page: 362End Page: 36
Experimental and theoretical study on optimizing caxBa1-xSnO3 perovskite materials as photoanode of dye-sensitized solar cells
The various compositions of CaxBa1βxSnO3 perovskite materials were synthesized by hydrothermal method and they were fabricated as the photoanode of dye-sensitized solar cells (DSSC). Among them, Ca0.1Ba0.9SnO3 composition shows better efficiency with the JSC of 4.64 mA cmβ2 and VOC of 0.726 V. The conduction band minimum (CBM) of Ca0.1Ba0.9SnO3 material is slightly lower than excited-state potential of N719 dye molecules. This provides high electron transfer from dye to this perovskite material after shining the light. The structural stability and electronic properties of these materials were studied by first principles density functional theory (DFT) calculations. Our study revealed that CBM is mainly distributed by Sn 5s states, which provides high electronic mobility. This mobility is not altered much even for substitution of small amount of Ca atoms into BaSnO3
Pharmacological evaluations of ethanol extract of Ficus benghalensis L. seeds for its antiulcer and antimicrobial efficacy
To evaluate the gastroprotective effect and antimicrobial efficacy of the seeds of Ficus benghalensis L. Acute oral toxicity study was performed according to the OECD test guidelines and the antiulcer assay was performed using ethanol-induced gastric ulcer model in albino rats. The antimicrobial activity and HPTLC analysis were also performed. The seed extract did not show any sign of toxicity at a dose of 4000 mg/kg body weight. Reductions in the ulcer index and gastric acid volume with increase in the pH of the gastric fluid in extract treated rats proved antiulcer activity. Increased levels of endogenous antioxidant enzymes superoxide dismutase and catalase with a decrease in lipid peroxidation in the extract treated animals demonstrated its antioxidant effect. The zone of inhibition was extremely great for all the tested microorganisms. HPTLC chromatogram showed a total of 9 peaks at different Rf values and peak area at 366 nm whereas seven peaks were observed at 254 nm. The number of peaks indicates the presence of constituents in the extract. Pre-treatment with F. benghalensis seed extract showed significant antiulcer activity that might be attributed to its antioxidant potential. F. benghalensis showed significant activity against bacteria and fungi. The extract containing phytoconstituents must have contributed to its antimicrobial activity
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