Herein, Cu was incorporated into ZnO lattice to reduce its band gap as well as to extend its visible radiation response. The obtained Cu-ZnO was continuously integrated with g-C3N4 to create ...Cu-ZnO/g-C3N4Z-direct scheme photocatalyst for advanced atrazine removal. Radical scavenging experiments have been also conducted to clearly figure out photocatalytic mechanism for degradation of atrazine by the synthesized photocatalyst. The synthesized Cu-ZnO only utilized the generated h+ for atrazine degradation (direct and indirect via formation hydroxyl radicals (•OH)) and the g-C3N4 only utilized the generated e− for atrazine degradation (indirect via reaction with O2 to form superoxide anion, which needed to continuously react with H2O to form •OH). Therefore, the photocatalytic atrazine degradation by synthesized Cu-ZnO material was greater than that by synthesized g-C3N4 material. Cu-ZnO/g-C3N4 utilized both generated e− and h+ for degradation of atrazine. Thus, the photocatalytic atrazine degradation by the synthesized Cu-ZnO/g-C3N4 was greater than those of single g-C3N4 or Cu-ZnO materials. Finally, the conducted recycling experiments indicated great stability of synthesized Cu-ZnO/g-C3N4 during long-term atrazine degradation process opening new era for application of the material in practical systems.
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•Cu doped into ZnO lattice to reduce its band gap and to extend its visible radiation response.•Cu-ZnO was successfully combined with g-C3N4 to establish Z direct scheme system.•Z-scheme prevented fast recombination of e− and h+ and maintained their re-dox potential.•The Cu-ZnO/g-C3N4 utilized both generated e− and h+ for degradation of atrazine.•The Cu-ZnO/g-C3N4 showed excellent activity and stability during long-term photocatalysis.
There are various chemical, physical and biological methods that have been applied to remove antibiotic residuals from aqueous environment. We investigated the removal of ampicillin (AMP) by a novel ...nanometer-size Fe
3
O
4
/graphene oxide/aminopropyltrimethoxysilane (FGOA). Based on the sol-gel method, the graphene oxide (GO) was first modified by aminopropyltrimethoxysilane (APTMS) to form GOA material containing both acidic and basic surface functional groups. The nanomagnetic iron oxide was then decorated to the GOA surface at various weight ratios by ultra-sonication in ethanol, resulting in different FGOA samples. The as-synthesized FGOA had single-layer structure and parallel array-like well-distributed Fe
3
O
4
. In laboratory-scale, the AMP treatment efficiency by FGOA with the ratio of Fe
3
O
4
: GOA as 1:5 ratio reached the highest value around 94% within 100 min and only lost 1% after five regeneration cycles. The maximum adsorption capacity of FGOA was 294mg g
−1
, significantly much higher than the previously published materials applied to AMP uptake. Interestingly, the optimum pH of FGOA ranged extensively from 4 to 9, revealing high application potential to real wastewater without any pH adjustment. The reasonable mechanism might be mainly attributed to electrostatic attraction, hydrophilic, and
π-π
interaction.
Internet addiction (IA) is a common problem found in young Asians. This study aimed to study the influence of IA and online activities on health-related quality of life (HRQOL) in young Vietnamese. ...This study also compared the frequencies of anxiety, depression and other addiction of young Vietnamese with and without IA.
This study recruited 566 young Vietnamese (56.7% female, 43.3% male) ranging from 15 to 25 years of age via the respondent-driven sampling technique. Chi-squared, t-test and analysis of variance were used to compare young Vietnamese with and without IA. Regression analyses were used to examine the association between internet usage characteristics and HRQOL.
Results from this cross-sectional study showed that 21.2% of participants suffered from IA. Online relationship demonstrated significantly higher influences on behaviors and lifestyles in participants with IA than those without IA. Participants with IA were more likely to have problems with self-care, difficulty in performing daily routine, suffer from pain and discomfort, anxiety and depression. Contrary to previous studies, we found that there were no differences in gender, sociodemographic, the number of participants with cigarette smoking, water-pipe smoking and alcohol dependence between the IA and non-IA groups. IA was significantly associated with poor HRQOL in young Vietnamese.
IA is a common problem among young Vietnamese and the prevalence of IA is the highest as compared to other Asian countries. Our findings suggest that gender may not play a key role in IA. This can be an emerging trend when both genders have equal access to the internet. By studying the impact of IA on HRQOL, healthcare professionals can design effective intervention to alleviate the negative consequences of IA in Vietnam.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
1H-Benzo
d
imidazole (BMA) has been considered as an emerging pharmaceutical organic contaminant, leading to the increasing BMA detection in wastewaters and need to be removed from ecosystem. This ...study investigated a highly synergistic BMA chemisorption using a novel ternary cross-coupled nanohybrid γ-APTES-Fe
3
O
4
@PAN@rGO. Magnetic nanoparticles (Fe
3
O
4
) were in situ core-shell co-precipitated with polyacrylonitrile polymer (PAN). Then, the prepared Fe
3
O
4
@PAN was decorated on hexagonal arrays of reduced graphene oxide (rGO) inside the framework of γ-aminopropyltriethoxysilane (γ-APTES). The final nanohybrid γ-APTES-Fe
3
O
4
@PAN@rGO produced adjacent inter-fringe distances of 0.2–0.4 nm corresponded well to (111), (220), and (311) parallel sub-lattices with two oblique intersections at 90° right angle and 60° triangle. The BMA adsorption was favorable in neutral pH 7, aroused temperature (50 °C), and controlled by endothermic process. The identified maximum adsorption capacity of 221.73 mg g
−1
was 30% higher than the reported adsorbents. The adsorption mechanisms include ion exchange, hydrogen bond, dipole-dipole force, π-conjugation, electrostatic, and hydrophobic interaction.
Graphical abstract
The synthetic route of novel nanohybrid γ-APTES-Fe
3
O
4
@PAN@rGO was investigated. After BMA adsorption, the adsorbent surface was entirely changed, thus an efficiently facile magnetic separation within 8s. γ-APTES-Fe
3
O
4
@PAN@rGO formed different oblique intersections of 60° and 90° sub-lattices
Bioactive-guided phytochemical investigation of
L. growing in Vietnam led to the isolation of five
-atisanes, one
-
-atisane, and one lathyrane (ingol-type). The structures were elucidated as
-1
3
16
...17-tetrahydroxyatisane (
), ethyl
-3,4-
-4,16
,17-trihydroxyatisane-3-carboxylate (
),
-atisane-3-oxo-16
,17-acetonide (
),
-3
-acetoxy-16
,17-dihydroxyatisane (
),
-16
,17-dihydroxyatisane-3-one (
), calliterpenone (
), and ingol 12-acetate (
). Their chemical structures were unambiguously determined by analysis of one-dimensional (1D) and two-dimensional (2D) nuclear magnetic resonance (NMR) and high resolution mass spectrometry, as well as by comparison with literature data. Among them,
is a new compound while
is an ethylated artifact of
-3,4-
-4,16
,17-trihydroxyatisane-3-carboxylic acid, a new compound. Isolates were evaluated for alpha-glucosidase inhibition. Compound
showed the most significant inhibitory activity against alpha-glucosidase with an IC
value of 69.62 µM. Further study on mechanism underlying yeast alpha-glucosidase inhibition indicated that
could retard the enzyme function by noncompetitive.
A new natural Diels‐Alder adduct (3) was isolated from the leaves and stem bark of Artocarpus integer, along with seventeen known compounds (1, 2, and 4–18). Structural elucidation was conducted ...using NMR and HR‐ESI‐MS data, and comparisons were made with previous studies. Deoxyartonin I (3) exhibited the most potent α‐glucosidase inhibition (IC50 7.80±0.1 μM), outperforming the acarbose positive control. This was mixed‐mode inhibition, as indicated by the intersect in the second quadrant of each respective plot. An in silico molecular docking model and the pharmacokinetic features of 3 suggest that it is a potential inhibitor of enzyme α‐glucosidase, and is therefore a lead candidate as a drug against diabetes mellitus.
Kurz is widely used in folk medicine in Eastern Asia and is associated with various ethnopharmacological properties including hepatoprotective, antipyretic, analgesic, antidysenteric, and ...anthelmintic activities. Previous phytochemical investigations reported the presence of numerous triterpenes (mostly cycloartanes, ursanes, lupanes, and oleananes) along with dozens of flavonoids. However, the extracts of
and isolated flavonoids have not been evaluated for their alpha-glucosidase inhibition. In the frame of our efforts dedicated to the chemical investigation of Vietnamese medicinal plants and their biological activities, a phytochemical study of the MeOH extract of the leaves of
using bioactive guided isolation was undertaken. In this paper, the isolation and structure elucidation of twelve known compounds, 5-hydroxy-3,7,4'-trimethoxyflavone (
), ayanin (
), kumatakenin (
), rhamnocitrin (
), ombuin (
), myricetin-3,7,3',5'-tetramethyl ether (
), gardenin D (
), luteolin (
), apigenin (
), mearnsetin (
), isoorientin (
), and vitexin (
) were reported. Bromination was applied to compounds
and
to provide four new synthetic analogues
-
. All isolated and synthesized compounds were evaluated for alpha-glucosidase inhibition and antibacterial activity. Compounds
and
showed moderate antibacterial activity against methicillin-resistant
while others were inactive. All compounds failed to reveal any activity toward extended spectrum beta-lactamase-producing
. Compounds
,
,
-
, and
-
showed good alpha-glucosidase inhibition with IC
values in the range of 30.5-282.0 µM. The kinetic of enzyme inhibition showed that
and
were noncompetitive type inhibition against alpha-glucosidase. In silico molecular docking model indicated that compounds
and
were potential inhibitors against enzyme
-glucosidase.
Display omitted
•Successfully doped Cu into ZnO lattice to enhance its photocatalytic activity.•Cu dopant prevented recombination of photo-excited e− and h+ of the ZnO.•The Cu-ZnO exhibited excellent ...photocatalytic degradation of monocrotophos pesticide.•The optimal mole ratio of Cu/ZnO in the Cu-ZnO for degradation of monocrotophos was 3%.•The optimal pH for the photocatalytic degradation of monocrotophos was pH 7.
In the work, we successfully synthesized Cu doped ZnO materials for photocatalytic degradation of monocrotophos pesticide (MCP). The used Cu metal doped into the ZnO matrix created an intermediate band to excite electron from valence band (VB) to conduction band (CD) of the ZnO leading to increase in optical absorption, decrease in band gap as well as photocatalytic performance of the material. Hence, the synthesized photocatalyst showed intense activity for photocatalytic degradation of MCP into CO2, H2O and harmless inorganic ions even under visible radiation. We also investigated that the 3Cu-ZnO photocatalyst, which the weight ratio of Cu/ZnO was 3 wt%, showed the highest MCP degradation efficiency among these synthesized Cu-ZnO. The excess dopants tended to form CuO existing on ZnO surface. The formed CuO acted as a center for recombination of produced electrons and holes resulted in decrease in photocatalytic performance of the Cu-ZnO. Finally, we investigated that the optimal pH for the degradation of MCP by the synthesized Cu doped ZnO photocatalyst was pH 7.
AbstractThe harmful effects of cadmium (Cd) to human health associated to its structure and chemical form. Cd(II) pollution is classified as causing economic and environmental damages due to being a ...probable human carcinogen and its severe effects to ecosystems. This work asserted a facile synthesis and easy-to-collect adsorbent to remove Cd(II). The magnetic-graphene oxide-based nanocomposite was synthesized via a two-step process of coprecipitation and polymerization. The batch adsorption results indicated that the highest adsorption capacity could be reached over the wide pH range of 4.0–6.0. The adsorption isotherms and kinetic studies suggested that the Cd(II) adsorption followed a pseudo second-order model and the Langmuir model, took place in monolayer coverage, and was strongly controlled by chemisorption. The formation of ternary surface complexes through cross-linked nitrile groups under cadmium-promoted bridging type improved Cd(II) adsorption capacity. The thermodynamic studies are an indicator of endothermic reaction, which describes the feasible and spontaneous nature of Cd(II) adsorption behavior in the view of temperature from 20°C to 40°C. The maximum adsorption capacity of adsorbent for Cd(II) (270.27 mg g−1) was higher than those of most of previous researches. The magnetic graphene oxide (GO)-based nanocomposite was synthesized via a two-step process of co-precipitation and polymerization by polyacrylonitrile (PAN).
ZnO/graphene oxide (ZnO/GO) nanocomposites were synthesized by hydrothermal method using zinc acetate and graphite as precursors. Properties of synthesized materials were investigated by different ...physico-chemical techniques and their photocatalytic performance was evaluated with the aid of the photodegradation of methyl orange under UV irradiation. Impacts of reaction conditions such as pH of solutions, catalyst loading and initial concentration on photodegradation rate of synthesized photocatalysts were also investigated. TEM images showed that the average size of the synthesized ZnO was approximately 35 nm, being in good agreement with the obtained XRD results which revealed good dispersion of ZnO particles over the wrinkled GO layers. UV–Vis absorption spectra of these synthesized materials revealed that 5% ZnO/GO exhibited the highest visible light absorption. Photocatalytic experimental results showed that the highest photodegradation rates occurred in a neutral solution with an initial methyl orange (MO) concentration of 10 mg/L. After 2 h of reaction under UV irradiation, more than 95% of MO was degraded at optimal conditions. The photodegradation of MO followed the pseudo-first-order kinetics with apparent reaction rate constants in the range of 0.009–0.030 (min
−1
). ZnO/GO photocatalyst was relatively stable in neutral aqueous solutions during the photodegradation of MO, with a decrease of 6% in photocatalytic performance observed after four cycles compared with the first cycle.
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