Abstract
Aldehydes and ketones are widely found in biomass resources and play important roles in organic synthesis. However, the direct deoxygenative coupling of aldehydes or ketones to construct ...C(sp
3
)−C(sp
3
) bond remains a scientific challenge. Here we report a nickel−catalyzed reductive homo-coupling of moisture- and air-stable hydrazones generated in-situ from naturally abundant aldehydes and ketones to construct challenging C(sp
3
)−C(sp
3
) bond. This transformation has great functional group compatibility and can suit a broad substrate scope with innocuous H
2
O, N
2
and H
2
as the by-products. Furthermore, the application in several biological molecules and the transformation of PEEK model demonstrate the generality, practicability, and applicability of this novel methodology.
Utilizing plasmonic nanostructures for efficient and flexible conversion of solar energy into electricity or fuel presents a new paradigm in photovoltaics and photoelectrochemistry research. In a ...conventional photoelectrochemical cell, consisting of a plasmonic structure in contact with a semiconductor, the type of photoelectrochemical reaction is determined by the band bending at the semiconductor/electrolyte interface. The nature of the reaction is thus hard to tune. Here instead of using a semiconductor, we employed a ferroelectric material, Pb(Zr,Ti)O3 (PZT). By depositing gold nanoparticle arrays and PZT films on ITO substrates, and studying the photocurrent as well as the femtosecond transient absorbance in different configurations, we demonstrate an effective charge transfer between the nanoparticle array and PZT. Most importantly, we show that the photocurrent can be tuned by nearly an order of magnitude when changing the ferroelectric polarization in PZT, demonstrating a versatile and tunable system for energy harvesting.
To pursue high photocatalytic activity in visible-light region, the Fe(III) modified BiOCl ultrathin nanosheet (Fe(III)@BOC NS) has been firstly synthesized via a facile solvothermal approach. The ...morphological and compositional characterizations reveal that the thickness of the as-prepared Fe(III)@BOC NS is less than 5 atomic layer with the exposure of active 001 facets. And the Fe(III) doping and surface grafting result in a 0.58eV down-shift of the BiOCl conduction band minimum extending the light absorption from ultraviolet light to visible light region, as well as a promoted interfacial charge transfer upon visible light irradiation. Meanwhile, the Fe(III) modification introduces unique active sites on the surface of ultrathin nanosheet facilitating the surface reaction. Moreover, both of the appropriate self-induced electric field of 001 facets, and the shortened charge carrier diffusion length of ultrathin nanosheet enhance the separation and transfer efficiency of charge carriers. Therefore, by taking those advantages, we experimentally demonstrate that the Fe(III)@BOC NS is a high-efficiency visible-light photocatalyst for both of environment remediation and water splitting.
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•Fe(III) modified BiOCl ultrathin nanosheet was firstly synthesized.•The Fe(III) modification results a down-shifts of the conduction band minimum for BiOCl.•The Fe(III)@BOC NS has a five-fold increase of visible-light-photocatalytic degradation rate for organic pollutant.•The Fe(III) modified BOC NS has promoted the hydrogen production.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Becasue of the existence of interface Schottky barriers and depolarization electric field, ferroelectric films sandwiched between top and bottom electrodes are strongly expected to be used as a new ...kind of solar cells. However, the photocurrent with a typical order of μA/cm2 is too low to be practical. Here we demonstrate that the insertion of an n-type cuprous oxide (Cu2O) layer between the Pb(Zr,Ti)O3 (PZT) film and the cathode Pt contact in a ITO/PZT/Pt cell leads to the short-circuit photocurrent increasing 120-fold to 4.80 mA/cm2 and power conversion efficiency increasing of 72-fold to 0.57% under AM1.5G (100 mW/cm2) illumination. Ultraviolet photoemission spectroscopy and dark J–V characteristic show an ohmic contact on Pt/Cu2O, an n+–n heterojunction on Cu2O/PZT and a Schottky barrier on PZT/ITO, which provide a favorable energy level alignment for efficient electron-extraction on the cathode. Our work opens up a promising new method that has the potential for fulfilling cost-effective ferroelectric-film photovoltaic.
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IJS, KILJ, NUK, PNG, UL, UM
Lung cancer is one of the most common malignant tumors, and its death rate is much higher than that of colon, kidney, breast, and prostate cancers, and its 5-year survival rate is only 18%. Lung ...cancer has no specific clinical symptoms in its early stages and lacks effective detection, making early detection difficult. The survival rate for advanced lung cancer is meager, with a median survival of only 12 months for stage IIIB/IV non-small cell lung cancer treated with platinumbased chemotherapy. Exosomes could provide vital information for the early diagnosis of lung cancer and have the potential to become a tumor marker for lung cancer. In addition, scientists have proposed encouraging ways to treat lung cancer by loading drugs, proteins, microRNAs, and siRNAs into exosomes. Therefore, studying lung cancer exosomes and exosomal nano drugs will provide new ideas and approaches for the diagnosis and treatment of lung cancer. This paper reviews the progress of research on the biological functions of exosomes and exosomal nanomedicines and their applications in clinical practice.
The cleavage and formation of carbon-carbon bonds have emerged as powerful tools for structural modifications in organic synthesis. Although transition-metal-catalyzed decarbonylation of unstrained ...diaryl ketones provides a viable protocol to construct biaryl structures, the use of expensive catalyst and high temperature (>140
C) have greatly limited their universal applicability. Moreover, the direct activation of two inert C - C bonds in diaryl ketones without the assistance of metal catalyst has been a great challenge due to the inherent stability of C - C bonds (nonpolar, thermo-dynamically stable, and kinetically inert). Here we report an efficient light-driven transition-metal-free strategy for decarbonylation of unstrained diaryl ketones to construct biaryl compounds through dual inert C - C bonds cleavage. This reaction featured mild reaction conditions, easy-to-handle reactants and reagents, and excellent functional groups tolerance. The mechanistic investigation and DFT calculation suggest that this strategy proceeds through the formation of dioxy radical intermediate via a single-electron-transfer (SET) process between photo-excited diaryl ketone and DBU mediated by DMSO, followed by removal of CO
to construct biaryl compounds.
Efficient extraction of photogenerated charge carriers is of significance for acquiring a high efficiency for perovskite solar cells. In this paper, a systematic strategy for effectively engineering ...the charge extraction in inverted structured perovskite solar cells based on methylammonium lead halide perovskite (CH 3 NH 3 PbI 3−x Cl x ) is presented. Intentionally doping the chlorine element into the perovskite structure is helpful for obtaining a high open circuit voltage. The engineering is carried out by modifying the aluminium cathode with zirconium acetylacetonate, doping the hole transport layer of nickel oxide (NiO x ) with copper and using an advanced fluorine doped tin oxide (FTO) substrate. This improves the bandgap alignment of the whole device, and thus, is of great benefit for extracting the charge carriers by promoting the transport rate and reducing the trap states. Consequently, an optimized power conversion efficiency of 20.5% is realized. Insights into how to extract charge carriers efficiently with a minimum energy loss are discussed.
Using statistical methods to analyze and summarize the research data of the inclusion criteria, to provide a quantitative average effect size to interpret the influence of mindfulness yoga exercise ...on patients with different depressive symptoms, explain the therapeutic effect of mindfulness yoga therapy on depression and its possible mechanism of action, and provide new ideas for the clinical treatment of patients with depression.
Review Manage 5.4 software was used to comprehensively evaluate the effect of yoga exercise on depression interventions to provide a reference for improving mental health. CNKI, PubMed, Web of science, EBSCO were searched for all case-control research articles on yoga for depression from 2000 to 2022. After screening, data extraction and quality evaluation of randomized controlled trials (RCTs) by inclusion and exclusion criteria, a total of 22 studies with 2,216 patients were included, including 1,101 in the yoga intervention group and 1,115 in the control group.
The results showed a large heterogeneity in the literature on the effect of yoga exercise on depression, with a combined total effect size
= -1.53, 95%
(-1.96, -1.10),
< 0.00001.
Mindfulness yoga exercise is effective in preventing and treating depression and improving mental health, and may be considered as a non-medical, low-cost intervention as an adjunct to pharmacological treatment.
A method of constructing BiFeO
3
/Cu
2
O heterojunction on the surface of BiFeO
3
is reported by using sol–gel and magnetron sputtering. The photocurrent density of BiFeO
3
with heterostructure is ...6.8 times the original BiFeO
3
. The photoelectrochemical performance improvement of BiFeO
3
/Cu
2
O was due to the effective construction of heterojunctions, which improves the light absorption capacity, reduces the resistance in charge transfer and also effectively accelerates the separation and collection of photogenerated electron–hole pairs. This work provides a promising strategy to develop high-efficiency PEC electrodes, and has potential to be applied in the visible-light water splitting area.
Graphic Abstract
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Polydatin is a traditional Chinese medicine that provides myocardial protection after acute myocardial infarction (AMI). The study aim was to investigate the myocardial protection polydatin in H9c2 ...myocardial cells cultured in a hypoxic atmosphere and in a rat AMI model induced by ligating the left anterior descending coronary artery and treated with polydatin 100 mg/kg/day for 30 days. The involvement of Nrf2 in mediating the effects of polydatin was investigated in H9c2 cells following Nrf2 knockdown by transfection of siRNA. Polydatin suppressed hypoxia-induced H9c2 cell apoptosis and reactive oxygen species (ROS) generation by promoting Nrf2/HO-1 signaling. Nrf2 knockdown reversed the protective effects of polydatin against hypoxia-induced myocardial cell injury. The in vivo results were consistent with polydatin suppression of apoptosis and ROS generation in myocardial tissue by promotion of Nrf2/HO-1 signaling. In conclusion, polydatin effectively inhibited hypoxia- and AMI-induced myocardial damage by promotion of Nrf2/HO-1 signaling.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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