Currently, many kinds of organic pollutants in air and water have a negative impact on humans and the environment. Notably, as a type of new functional materials, metal-organic frameworks (MOFs) with ...well-ordered porous structures and numerous active sites have been proven to be ideal photocatalysts for the degradation of organic pollutants. In the past few years, many encouraging achievements have been made in the research field of MOFs for photocatalysis. And a large number of functionalized MOFs have been constructed to improve photocatalytic activity. In this review, recent progress in the photocatalytic degradation of organic pollutants in both air and water using functionalized MOFs are summarized in detail. The focus is on photocatalytic mechanisms and some strategies employed to achieve higher degradation efficiency. Furthermore, the challenges and outlooks in this promising filed are also discussed. We hope this review would be useful for designing more functionalized MOFs with greater photocatalytic performance for the degradation of organic pollutants in the environment.
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•The latest progress on photocatalytic degradation of organic pollutants in air and water using functionalized MOFs are reviewed.•Some strategies to improve the degradation efficiency are presented.•The photocatalytic mechanisms are summarized.•The challenges and outlooks of MOFs for photocatalytic degradation of organic pollutants are given.
Two aldehyde‐modified tetraphenylene derivatives with different functionality are synthesized and exhibit different fluorescence properties. By incorporating tetraphenylene derivatives into ...polydimethylsiloxane (PDMS) networks, two elastomers are prepared through dynamic covalent cross‐linking. The elastomers show excellent fluorescence properties, mechanical properties, thermal stability as well as self‐healing and recycle properties. At the same time, the mechanical properties of the elastomers are influenced by the functionality of the tetraphenylene derivatives and the molecular weight of the PDMS. The self‐healing process takes place quickly and the recycling process can be carried out by solution processing and hot pressing. It shows the similar tensile properties between the pristine and healed samples.
By incorporating tetraphenylene derivatives into polydimethylsiloxane (PDMS) networks, two elastomers were prepared through dynamic covalent cross‐linking, which showed interesting fluorescent properties, mechanical properties, and excellent self‐healing properties.
Muon (g − 2) in the B-LSSM Yang, Jin-Lei; Zhang, Hai-Bin; Liu, Chang-Xin ...
The journal of high energy physics,
08/2021, Volume:
2021, Issue:
8
Journal Article
Peer reviewed
Open access
A
bstract
The difference between the updated experimental result on the muon anomalous magnetic dipole moment and the corresponding theoretical prediction of the standard model on that is about 4
.
2 ...standard deviations. In this work, we calculate the muon anomalous MDM at the two-loop level in the supersymmetric
B − L
extension of the standard model. Considering the experimental constraints on the lightest Higgs boson mass, Higgs boson decay modes
h → γγ
,
WW
,
ZZ
,
b
b
¯
,
τ
τ
¯
, B rare decay
B
¯
→ X
s
γ
, and the transition magnetic moments of Majorana neutrinos, we analyze the theoretical predictions of the muon anomalous magnetic dipole moment in the
B − L
supersymmetric model. The numerical analyses indicate that the tension between the experimental measurement and the standard model prediction is remedied in the
B − L
supersymmetric model.
Modification of pristine biochars has received increasing attentions due to the significant potential in enhancing adsorption performance. In this work, the co-modification of KOH and KMnO4 on ...biochar (K-Mn-BC) was performed, with the effect of KOH/KMnO4 modification on biochar properties and their adsorption toward tetracycline (TC) being extensively explored. Results showed that KOH/KMnO4 modification can significantly regulate biochars to form hierarchical structure. The obtained K-Mn-BC was characterized with a high specific surface area (1524.6 m2 g−1) and total pore volume (0.85 cm3 g−1). In addition, the K-Mn-BC exhibited a high adsorption capacity of 584.19 mg g−1 toward TC at 318 K, and pseudo-second-order (R2:0.993～0.998) and Langmuir (R2: 0.834～0.874) models can fit well with the adsorption behavior. Moreover, the obtained K-Mn-BC can efficiently adsorb TC within a wide pH range (3.0–10.0), and were not affected by the co-existing ions. The possible mechanisms for the high adsorption capacity were ascribed to the pore filling and π-π interaction, following by hydrogen bonding and metal complexation. The obtained K-Mn-BC is a suitable adsorbent for TC removal from water due to the hierarchical structure, high adsorption capacity, and stable adsorption effect.
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•Co-modification of KOH and KMnO4 on biochar for enhanced TC adsorption was studied.•K-Mn-BC exhibited a hierarchical structure.•Pseudo-second-order and Langmuir models can well fit the adsorption behavior.•The maximum adsorption capacity of K-Mn-BC toward was 584.19 mg g−1.•The prevailing mechanisms of TC on K-Mn-BC were revealed.
Long non‐coding RNAs (lncRNAs) serve critical roles in the pathogenesis of various cancers, including lung adenocarcinoma (LUAD). Herein, in this study, we aimed to investigate the biological and ...clinical significance of lncRNA DiGeorge syndrome critical region gene 5 (DGCR5) in LUAD. It was observed that DGCR5 was upregulated in LUAD tissues and LUAD cell lines. Inhibition of DGCR5 can prevent LUAD progression via playing anti‐apoptosis roles. Both mRNA expression and protein levels of BCL‐2 were increased by DGCR5 downregulation while reversely BAX was increased. Additionally, a novel microRNA target of DGCR5, hsa‐mir‐22‐3p was identified through bioinformatics search and confirmed by dual‐luciferase reporter system. Gain and loss‐of‐function studies were performed to verify whether DGCR5 exerts its biological functions through regulating hsa‐mir‐22‐3p in vitro. Overexpression of DGCR5 was able to reverse the tumor inhibitory effect of hsa‐mir‐22‐3p mimics. Furthermore, in vivo tests tumor xenografts were established to detect the function of DGCR5 in LUAD tumorigenesis. Downregulated DGCR5 expression was greatly associated with smaller tumor size, implying a favorable prognosis of LUAD patients. Taken these together, DGCR5 could be considered as a prognostic biomarker and therapeutic target in LUAD diagnosis and treatment.
Our findings in LUAD cell lines and xenografts support the use of DGCR5 as an oncogene to promote LUAD development. This is the first reporting of a possible mechanism for a crosstalk between DGCR and hsa‐mir‐22‐3p crosstalk in LUAD. These results suggest DGCR5 as a potential target for LUAD treatment.
A
bstract
Based on the gauge symmetry group SU(3)
C
⨂ SU(2)
L
⨂ U(1)
Y
⨂ U(1)
B–L
, the minimal supersymmetric extension of the SM with local B-L gauge symmetry(B-LSSM) has been introduced. In this ...model, we study the Higgs masses with the one-loop zero temperature effective potential corrections. Besides, the finite temperature effective potentials connected with two U(1)
B-L
Higgs singlets are deduced specifically. Then we can obtain the gravitational wave spectrums generated from the strong first-order phase transition. In the B-LSSM, with the fine-tuned parameter regions, we can obtain the strength parameter
α
θ
~ 0.14 and the ratio of speed to Hubble rate
β
/
H
n
~ 5 at nucleation temperature, and then obtain observable gravitational wave signals. The gravitational wave signals can be as strong as
h
2
Ω
GW
~ 10
–9
, which may be detectable in the future experiments.
Three-dimensional genome structures play a key role in gene regulation and cell functions. Characterization of genome structures necessitates single-cell measurements. This has been achieved for ...haploid cells but has remained a challenge for diploid cells. We developed a single-cell chromatin conformation capture method, termed Dip-C, that combines a transposon-based whole-genome amplification method to detect many chromatin contacts, called META (multiplex end-tagging amplification), and an algorithm to impute the two chromosome haplotypes linked by each contact. We reconstructed the genome structures of single diploid human cells from a lymphoblastoid cell line and from primary blood cells with high spatial resolution, locating specific single-nucleotide and copy number variations in the nucleus. The two alleles of imprinted loci and the two X chromosomes were structurally different. Cells of different types displayed statistically distinct genome structures. Such structural cell typing is crucial for understanding cell functions.
Evaluating the bioavailability of Cd to rice (Oryza sativa L.) was essential in the karst region, Southwestern China, where the soils have previously been shown to be anomalously enriched in Cd ...through geogenic processes. In this research, we examined the bioavailability of Cd to rice samples collected from 278 sites in Guangxi province, where rice is the most widely cultivated cereal crop that is responsible for the largest human dietary exposure to Cd. Both soil chemical extraction and soil-plant transfer modelling approaches were used to predict the bioavailability to rice. Some of the soil types were highly enriched in Cd, but their bioavailability was low, since the soil carbonates raised soil pH and remarkably reduced Cd bioavailability. In contrast, acidic soils (Ca was largely leached) with relatively low total Cd, the grown rice plants accumulated higher Cd in their grains. Results from CaCl2 extraction experiments provided good predictions for Cd in rice grain grown in soils of different types. Stepwise multiple regressions revealed soil pH and soil Ca content were the dominant factors that control the transfer of Cd from soil to rice. An extended Freundlich-type model and a polynomial surface model provided good prediction for Cd in rice grains. The diffusive gradients in thin films (DGT) technique gave the best estimation of soil Cd bioavailability, whereas water-extracted soil solution Cd provided relatively poor fits. Regional soil threshold that derived using the models, can avoid exceedance of Cd in rice and thereby enable local agricultural practitioners or authorities to develop appropriate management for croplands with high Cd background.
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•The bioavailability of Cd in soils with high geochemical background was characterized as highly soil-type dependent.•Soil Ca, pH, and total Cd are the controlling factors of Cd bioavailability.•The DGT technique was a better approach to assess Cd bioavailability to rice.•Derived regional soil threshold can prevent exceedance of Cd in rice.
Using various approaches to characterize soil behaviors and the bioavailability of Cd to rice grown in high Cd background soils derived under unique karst geologies.
Divergent enantioselective total syntheses of five naturally occurring post‐iboga indole alkaloids, dippinine B and C, 10,11‐demethoxychippiine, 3‐O‐methyl‐10,11‐demethoxychippiine, and ...3‐hydroxy‐3,4‐secocoronaridine, as well as the two analogues 11‐demethoxydippinine A and D, are presented for the first time. The enantioenriched aza3.3.1‐bridged cycle, a common core intermediate to the target molecules, was constructed through an asymmetric phase‐transfer‐catalyzed Michael/aldol cascade reaction. The challenging azepane ring fused around the indole ring and the 3.3.1‐bridged cycle were installed through an intramolecular SN2′‐type reaction. These cyclization strategies enabled rapid construction of the 6.5.6.6.7‐pentacyclic core at an early stage. Highlights of the late‐stage synthetic steps include a Pd‐catalyzed Stille coupling and a highly stereoselective catalyst‐controlled hydrogenation to incorporate the side chain at C20 with both R and S configurations in the natural products.
Enantioselective total syntheses of post‐iboga indole alkaloids were achieved in a divergent manner. The construction of the 6.5.6.6.7‐pentacyclic core included an asymmetric Michael/aldol cascade reaction for installing the aza3.3.1‐bridged cycle and an intramolecular SN2′‐type reaction for assembling the azepane ring. The stereoselective incorporation of the side chain involved a Pd‐catalyzed Stille coupling and a catalyst‐controlled hydrogenation.
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