Metal‐free elemental photocatalysts for hydrogen (H2) evolution are more advantageous than the traditional metal‐based inorganic photocatalysts since the nonmetal elements are generally cheaper, more ...earth‐abundant, and environmentally friendly. Black phosphorus (BP) has been attracting increasing attention in recent years based on its anisotropic 2D layered structure with tunable bandgap in the range of 0.3–2.0 eV; however, the application of BP for photocatalytic H2 evolution has been scarcely reported experimentally although being theoretically predicted. Herein, for the first time, the visible light photocatalytic H2 evolution of BP nanosheets prepared via a facile solid‐state mechanochemical method by ball‐milling bulk BP is reported. Without using any noble metal cocatalyst, the visible light photocatalytic hydrogen evolution rate of BP nanosheets reaches 512 µmol h−1 g−1, which is ≈18 times higher than that of the bulk BP, and is comparable or even higher than that of graphitic carbon nitrides (g‐C3N4).
Black phosphorus (BP) is discovered as the missing metal‐free elemental photocatalyst. Few‐layer BP nanosheets are prepared via a facile solid‐state mechanochemical method, exhibiting a visible light H2 evolution rate of 512 µmol h−1 g−1 without using any noble metal cocatalyst, which is increased by ≈18 times relative to that of bulk BP. Thus the missing photocatalytic property of BP is discovered.
Reduced graphene oxide/Fe2O3 composite was prepared using a facile two-step synthesis by homogeneous precipitation and subsequent reduction of the G-O with hydrazine under microwave irradiation to ...yield reduced graphene oxide (RG-O) platelets decorated with Fe2O3 nanoparticles. As an anode material for Li-ion batteries, the RG-O/Fe2O3 composite exhibited discharge and charge capacities of 1693 and 1227 mAh/g, respectively, normalized to the mass of Fe2O3 in the composite (and ∼1355 and 982 mAh/g, respectively, based on the total mass of the composite), with good cycling performance and rate capability. Characterization shows that the Fe2O3 nanoparticles are uniformly distributed on the surface of the RG-O platelets in the composite. The total specific capacity of RG-O/Fe2O3 is higher than the sum of pure RG-O and nanoparticle Fe2O3, indicating a positive synergistic effect of RG-O and Fe2O3 on the improvement of electrochemical performance. The synthesis approach presents a promising route for a large-scale production of RG-O platelet/metal oxide nanoparticle composites as electrode materials for Li-ion batteries.
The main purpose of this paper is to show Wirtinger type inequalities for the pseudo-integral. We are concerned with pseudo-integrals based on the following three canonical cases: in the first case, ...the real semiring with pseudo-operation is generated by a strictly monotone continuous function
g
; in the second case, the pseudo-operations include a pseudo-multiplication and a power arithmetic addition; in the last case, ⊕-measures are interval-valued. Examples are given to illustrate these equalities.
As an essential part of classical analysis, Ostrowski and Čebyšev type inequalities have recently attracted considerable attention. Due to its universality, the non-additive integral inequality takes ...several forms, including Sugeno integrals, Choquet integrals, and pseudo-integrals. Set-valued analysis, a well-known generalization of classical analysis, is frequently employed in studying mathematical economics, control theory, etc. Inspired by pioneering work on interval-valued inequalities, this paper establishes specific Ostrowski and Čebyšev type inequalities for interval-valued functions. Moreover, the error estimation to quadrature rules is presented as some applications for illustrating our results. In addition, illustrative examples are offered to demonstrate the applicability of the mathematical methods presented.
Abstract
Few-layer black phosphorus (BP) with an anisotropic two-dimensional (2D)-layered structure shows potential applications in photoelectric conversion and photocatalysis, but is easily oxidized ...under ambient condition preferentially at its edge sites. Improving the ambient stability of BP nanosheets has been fulfilled by chemical functionalization, however this functionalization is typically non-selective. Here we show that edge-selective functionalization of BP nanosheets by covalently bonding stable C
60
molecules leads to its significant stability improvement. Owing to the high stability of the hydrophobic C
60
molecule, C
60
functions as a sacrificial shield and effectively protects BP nanosheets from oxidation under ambient condition. C
60
bonding leads to a rapid photoinduced electron transfer from BP to C
60
, affording enhanced photoelectrochemical and photocatalytic activities. The selective passivation of the reactive edge sites of BP nanosheets by sacrificial C
60
molecules paves the way toward ambient processing and applications of BP.
Nanorod vanadium sulfide wrapped by reduced graphene oxide (rGO) composite is synthesized by a facile solvothermal reaction. Nanorod vanadium sulfide is uniformly distributed on the surface of rGO ...nanosheets. As an anode for sodium ion batteries, the composite with 13 wt% rGO has 1203.8 and 781.4 mAh g−1 specific capacities for the first discharge and charge, respectively, with 64.9% of Coulombic efficiency, higher than that of pure vanadium sulfide submicrospheres. The sodiation/desodiation mechanism is investigated by cyclic voltammetry, electrochemical impedance spectrum and discharging-charging measurement. The results show that the vanadium sulfide/rGO composite can convert to sodium sulfide + vanadium/rGO composite after the first cycle, and the rGO can inhibit the dissolution of polysulfide while metal vanadium increases electrode conductivity, resulting in the enhanced electrochemical performance.
•VS4/rGO can deliver a reversible capacity of 781.4 mAh g-1.•The mechanism of storage sodium for VS4/rGO is investigated.
► We report a facile synthesis of a ‘graphene’-SnO2 composite by homogeneous coprecipitation. ► SnO2 nanoparticles are decorated uniformaly on the surface of reduced graphene oxide platlets. ► As an ...anode material for Li-ion battery, the RG-O/SnO2 composite exhibits discharge and charge capacities of 2140 and 1080 mAh/g at the first cycle, respectively, with good cycling performance. ► The synthesis approach presents a promising route for large scale production of RG-O platelet/metal oxide nanoparticle composites as electrode materials.
Reduced graphene oxide/tin oxide composite is prepared by homogenous coprecipitation. Characterizations show that tin oxide particles are anchored uniformly on the surface of reduced graphene oxide platelets. As an anode material for Li ion batteries, it has 2140mAhg−1 and 1080mAhg−1 capacities for the first discharge and charge, respectively, which is more than the theoretical capacity of tin oxide, and has good capacity retention with a capacity of 649mAhg−1 after 30 cycles. The simple synthesis method can be readily adapted to prepare other composites containing reduced graphene oxide as a conducting additive that, in addition to supporting metal oxide nanoparticles, can also provide additional Li binding sites to, perhaps, further enhance capacity.
Defective rhodopsin homeostasis is one of the major causes of retinal degeneration, including the disease Retinitis pigmentosa. To identify cellular factors required for the biosynthesis of ...rhodopsin, we performed a genome-wide genetic screen in Drosophila for mutants with reduced levels of rhodopsin. We isolated loss-of-function alleles in endoplasmic reticulum membrane protein complex 3 (emc3), emc5, and emc6, each of which exhibited defective phototransduction and photoreceptor cell degeneration. EMC3, EMC5, and EMC6 were essential for rhodopsin synthesis independent of the ER associated degradation (ERAD) pathway, which eliminates misfolded proteins. We generated null mutations for all EMC subunits, and further demonstrated that different EMC subunits play roles in different cellular functions. Conditional knockout of the Emc3 gene in mice led to mislocalization of rhodopsin protein and death of cone and rod photoreceptor cells. These data indicate conserved roles for EMC subunits in maintaining rhodopsin homeostasis and photoreceptor function, and suggest that retinal degeneration may also be caused by defects in early biosynthesis of rhodopsin.
Phospholipids are asymmetrically distributed across the mammalian plasma membrane, with phosphatidylserine (PS) and phosphatidylethanolamine concentrated in the cytoplasmic leaflet of the membrane ...bilayer and phosphatidylcholine in the exoplasmic leaflet. This asymmetric distribution is dependent on a group of P4 ATPases called PS flippases. The proper transport and function of PS flippases require a β‐subunit transmembrane protein 30A (TMEM30A). Disruption of PS flippases leads to several human diseases. Tmem30a is essential for photoreceptor survival. However, the roles of Tmem30a in the retinal rod bipolar cells (RBC) remain elusive. To investigate the role of Tmem30a in the RBCs, we generated a RBC‐specific Tmem30a knockout (cKO) mouse model using PCP2‐Cre line. The Tmem30a cKO mice exhibited defect in RBC function and progressive RBC death. PKCα staining of retinal cryosections from cKO mice revealed a remarkable dendritic sprouting of rod bipolar cells during the early degenerative process. Immunostaining analysis of PSD95 and mGluT6 expression demonstrated that rod bipolar cells in Tmem30a cKO retinas exhibited aberrant dendritic sprouting as a result of impaired synaptic efficacy, which implied a crucial role for Tmem30a in synaptic transmission in the retina. In addition, loss of Tmem30a led to reactive gliosis with increased expression of glial fibrillary acidic protein and CD68. TUNEL staining suggested that apoptotic cell death occurred in the retinal inner nuclear layer (INL). Our data show that loss of Tmem30a in RBCs results in dendritic sprouting of rod bipolar cells, increased astrogliosis and RBC death. Taken together, our studies demonstrate an essential role for Tmem30a in the retinal bipolar cells.
Cover Image for this issue: doi: 10.1111/jnc.14492.
Tmem30a play essential roles in synaptic maintenance and survival of rod bipolar cells (RBC). Loss of Tmem30a in RBC led to significantly compromised RBC function, as revealed by reduced scotopic b wave amplitude of electroretinogram. Abberrant dendritic sprouting in the synapse and overactivation of astrocyte and microglia, which in turn cause reactive gliosis, resulted in progressive death of RBC.
Cover Image for this issue: doi: 10.1111/jnc.14492.
The human HSP70 family is a type of heat shock protein (HSP), consisting of 13 members encoded by the HSPA genes. HSPs play important roles in regulating cellular responses and functions during ...carcinogenesis, but their relationship with colon cancer is unclear. In our study, we found that the expressions of HSPA1B, HSPA4, HSPA5, HSPA6, HSPA8, HSPA9, HSPA13, and HSPA14 were significantly increased, while those of HSPA1A, HSPA2, HSPA7, and HSPA12B were significantly decreased in colon cancer tissues. The expression of HSPA gene family members was associated with some clinicopathological characteristics, including age, gender, TNM stage, pathological stage, and CEA level. Furthermore, the Kaplan–Meier method and Cox regression analysis showed that high HSPA1A, HSPA1B, and HSPA7 expressions were related to unfavorable survival, and high HSPA9 was associated with favorable survival. The relationships between HSPA1A and HSPA9 expression and survival were validated in the GEO dataset, and the HSPA1A and HSPA9 protein expression differences between colon cancer tissues and normal tissues were validated in the UALCAN database. Methylation of HSPA1A and HSPA9 was also analyzed, and it was found that the methylation of the HSPA1A promoter was significantly increased, and the methylation of the HSPA9 promoter was significantly decreased in colon cancer tissues. Increasing the methylation level of the HSPA1A gene and decreasing the methylation level of HSPA9 were related to favorable prognosis. The expression difference of HSPA1A/HSPA1B/HSPA7/HSPA9 was verified in colon cancer cell lines and colonic epithelial cells. Gene ontology analysis was used to screen signal pathways related to HSPA1A-, HSPA1B-, HSPA7-, and HSPA9- high phenotype. In summary, the increased expressions of HSPA1A1, HSPA1B, and HSPA7 were associated with poor prognosis, while that of HSPA9 was related to favorable prognosis for colon cancer patients.
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