Structural defects can greatly inhibit electron transfer in two-dimensional (2D) layered polymeric carbon nitride (CN) unit, seriously lowering its utilization ratio of photogenerated charges during ...photocatalysis. Herein, we propose a new strategy based on intra-melon hydrogen bonding interactions in 2D CN frameworks to improve the crystallinity of CN. This concept was validated by removing some amino groups and connecting melon using codoped B and F atoms via a simple one-step sodium fluoroborate-assisted thermal treatment. The enhancement in crystallinity effectively promoted exciton dissociation and charge transfer in the CN nanosheets. Furthermore, the B/F dopants also improved the separation of photogenerated carriers by promoting charge capture. The highly efficient visible-light photocatalytic activity of the crystalline B/F-codoped CN nanosheets was demonstrated by degrading methyl orange, Rhodamine B, colorless phenol and tetracycline hydrochloride as models, where their degradation rate constant was more than 10, 5, 32 and 3 times higher than that of pure CN, respectively. Moreover, the B/F-codoped CN exhibited an excellent photoelectrocatalytic performance for the oxygen evolution reaction (OER), outperforming the precious-metal IrO2 catalyst. The simple and effective strategy proposed herein provides a direct route to engineer high crystallinity in 2D materials for tunable charge carrier separation and migration for electronic and optoelectronic applications.
Network structures based on Star‐of‐David catenanes with multiple superior functionalities have been so far elusive, although numerous topologically interesting networks are synthesized. Here, a ...metal–organic framework featuring fused Star‐of‐David catenanes is reported. Two triangular metallacycles with opposite handedness are triply intertwined forming a Star‐of‐David catenane. Each catenane fuses with its six neighbors to generate a porous twofold intercatenated gyroid framework. The compound possesses exceptional stability and exhibits multiple functionalities including highly selective CO2 capture, high proton conductivity, and coexistence of slow magnetic relaxation and long‐range ordering.
A metal–organic framework, which represents the rare networks composed of Star‐of‐David catenanes, is designed. The structural complexity of the unique framework highlights different facets of the same compound. Remarkably, the material shows highly selective CO2 capture for a molecular‐sieving effect, superionic proton conductivity, and coexistence of slow magnetic relaxation and long‐range ordering.
Uromodulin, also named Tamm Horsfall protein, have been associated with renal function and sodium homeostasis regulation. The authors sought to examine the effects of salt intake on plasma and ...urinary uromodulin levels and the association of its genetic variants with salt sensitivity in Chinese adults. Eighty patients from our natural population cohort were maintained sequentially either on a usual diet for 3 days, a low‐salt diet (3.0 g) for 7 days, and a high‐salt diet (18.0 g) for an additional 7 days. In addition, the authors studied 514 patients of the Baoji Salt‐Sensitive Study, recruited from 124 families who received the same salt intake intervention, and investigated the association of genetic variations in uromodulin gene with salt sensitivity. Plasma uromodulin levels were significantly lower on a high‐salt diet than on a baseline diet (28.3 ± 4.5 vs. 54.9 ± 8.8 ng/ml). Daily urinary excretions of uromodulin were significantly decreased on a high‐salt diet than on a low‐salt diet (28.7 ± 6.7 vs. 157.2 ± 21.7 ng/ml). SNPs rs7193058 and rs4997081 were associated with the diastolic blood pressure (DBP), mean arterial pressure (MAP) responses to the high‐salt diet. In addition, several SNPs in the uromodulin gene were significantly associated with pulse pressure (PP) response to the low‐salt intervention. This study shows that dietary salt intake affects plasma and urinary uromodulin levels and that uromodulin may play a role in the pathophysiological process of salt sensitivity in the Chinese populations.
Interactions between microorganisms and clay minerals are ubiquitous in nature and are involved in the formation and transformation of clay minerals and the global cycles of many elements. The ...fungi/actinomyces in microbes are also associated with clay minerals, but bacteria are more widely linked. These interactions are also involved in the adsorption and fixation of heavy metals and the decomposition of organic pollutants in soil. Knowledge of these interactions can be utilised for the refinement and purification of clay minerals in industry. This review provides an overview of recent studies and obtains insights into the interactions between microorganisms and clay minerals. Microorganisms can induce the nucleation and growth of clay minerals. The metabolism of microorganisms can also degrade and transform clay minerals. The interaction between microorganisms and clay minerals promots the transformation of smectite to illite (S-I) and vice versa (I-S). Such interactions significantly contribute to the global cycles of various elements, such as Al, Si, Mg, Fe, P, S, C, and N. Microorganisms and clay minerals can form complexes and composite materials that adsorb heavy metals such as Cu, Cr, Cd, Pb, Zn, Co, Ni, Ag, and Hg. Microorganism adhesion to clay minerals is involved in the synergistic adsorption and decomposition of organic pollutants in soil and water. This literature review indicates that knowledge of the interactions between microorganisms and clay minerals has been significantly deepened over recent years. However, the interaction between microorganisms and clay minerals under natural geological conditions and the inherent mechanisms involved are not yet well understood. Future work on interactions between microorganisms and clay minerals has great implications for handling atmospheric micro/nano particle pollutants, understanding the formation, alteration and diagenesis of clay minerals and other related minerals, tracking primitive life on Earth and exploring extraterrestrial planets.
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•Recent insights into interactions between microorganisms and clay minerals•Roles of microorganisms in formation and transformation of clay minerals•Global cycles of elements, soil formation and organic matter preservation•Adsorption and elimination of pollutants and purification of clay minerals•Future work on interactions between microorganisms and clay minerals
A method for the preparation of chiral triarylmethanes via organocatalytic 1,6‐addition of arylboronic acids to para‐quinone methides (p‐QMs) was established. Here the use of salicylaldehyde‐derived ...p‐QMs with an ortho‐hydroxy substituent as a directing group was essential for the remote stereocontrol. In the presence of a BINOL catalyst, chiral triarylmethanes can be obtained in high yields (up to 99%) with excellent enantioselectivities (up to 99% ee). This method shows broad substrate tolerance and can be easily scaled up, both electron‐rich and electron‐deficient arylboronic acids are suitable substrates for this addition reaction.
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•Host–guest supramolecular self-assembly strategy increases π-electron density.•The strategy overcomes one of the major challenges of copolymeration method.•CN-C is hierarchical ...porous nanocages with wall thickness of about 20.0 nm.•The π-electron-rich CN-C nanocages is demonstrated to promote charge transfer in CN.•The efficient HER activity of CN-C nanocages are achieved.
Converting solar energy into renewable clean fuels of hydrogen via photocatalytic water splitting provides the most prospective strategy for tackling the energy and environmental issues. The performance of most photocatalysts is closely related to the intrinsic activity and active edge sites; however, simultaneously regulating them to realize synergic effects remains significant scientific and technological challenge. Here, we report an elaborate design and synthesis of porous carbon nitride nanocages (CN-C) with abundant π-electron densities by a novel host–guest supramolecular self-assembly strategy, overcoming one of the major challenges of traditional copolymeration method, i.e., the required highly matched chemical structure and physical properties of the π-electron-rich monomers to nitrogen-rich monomers. This strategy primarily depends on the cooperation of the host supramolecular precursor growth and the self-regulation of guest supermolecules to compensate the inherent shortage of each component. Interestingly, the structural topology and electron densities of CN-C are found to be easily modulated by only varying the amount of urea. Benefiting from the synergic effects of hierarchically porous structures with enriched active sites and excellent accessibility, increased abundant π-electron densities and improved visible-light absorption, the CN-C nanocages exhibit remarkable photocatalytic hydrogen evolution activity under visible light exposure with H2 generation rate of 1135 μmol h−1g−1, which is 19 times higher than that of pristine CN (59.8 μmol h−1g−1). This powerful strategy provides a profound molecular-level insight into the control of morphology and π-electron densities within carbon-based materials.
This paper summarized and collated international literatures on graphene organic anticorrosion coatings in recent ten years and hierarchical and organized knowledge structures were formed. According ...to the role of graphene, from the perspective of theoretical and applied research, the improvement of graphene on organic anti-corrosion coatings were reviewed. In terms of the improvement of graphene on the shielding effect of coatings, the paper discussed the dispersion methods and orientation technology of graphene. A variety of graphene dispersion methods reported in the literatures were systematically organized according to dispersant groups, modification mechanisms, dispersion mechanisms and preparation processes. In terms of functional synergy, the functionalization of graphene was divided into two aspects. They were enhancement of adhesion and self-healing of the coatings. The increase in adhesion was attributed to the covalent bonds between the functional groups on the surface of graphene and the metal matrix. In the studies on self-healing of the coatings based on modified graphene, graphene acted as the load platform for self-healing functional groups. According to the self-healing groups supported by graphene, the self-healing mechanism was divided into catalytic passivation film and corrosion inhibitor adsorption film. Then, the paper discussed the practical problems and doubts encountered in the research and application of graphene in the field of anticorrosion, and that was the local corrosion acceleration phenomenon caused by the conductivity of graphene. Meanwhile, the way to solve the promotion of local corrosion were proposed. Finally, from the macroscopic, mesoscopic and microscopic perspectives, the paper summarized and discussed the influence mechanism of graphene conductivity and its orientation on the shielding effect and cathodic protective performance of zinc-rich coatings.
•International papers on graphene organic anti-corrosion coatings were reviewed.•A variety of graphene dispersion methods were systematically organized.•Enhancement of adhesion and self-healing by graphene was summarized.•Graphene-zinc coatings were reviewed from macro, meso and micro perspectives.
Graves' disease is a common autoimmune disorder characterized by thyroid stimulating hormone receptor autoantibodies (TRAb) and hyperthyroidism. To investigate the genetic architecture of Graves' ...disease, we conducted a genome-wide association study in 1,536 individuals with Graves' disease (cases) and 1,516 controls. We further evaluated a group of associated SNPs in a second set of 3,994 cases and 3,510 controls. We confirmed four previously reported loci (in the major histocompatibility complex, TSHR, CTLA4 and FCRL3) and identified two new susceptibility loci (the RNASET2-FGFR1OP-CCR6 region at 6q27 (Pcombined = 6.85 × 10−10 for rs9355610) and an intergenic region at 4p14 (Pcombined = 1.08 × 10−13 for rs6832151)). These newly associated SNPs were correlated with the expression levels of RNASET2 at 6q27, of CHRNA9 and of a previously uncharacterized gene at 4p14, respectively. Moreover, we identified strong associations of TSHR and major histocompatibility complex class II variants with persistently TRAb-positive Graves' disease.
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Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
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