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Two-dimensional (2D) materials have attracted great attention in the field of photodetection due to their excellent electronic and optoelectronic properties. However, the weak optical absorption caused by atomically thin layers and the short lifetime of photocarriers limit their optoelectronic performance, especially for weak light detection. In this work, we design a high-gain photodetector induced by carrier recirculation based on a vertical InSe/GaSe heterojunction. In this architecture, the photogenerated holes are trapped in GaSe due to the built-in electric field, suppressing the recombination rate of photocarriers, so the electrons can recirculate for multiple times in the InSe channel following the generation of a single electron-hole pair, resulting a high photoconductive gain (10

Organic solvent nanofiltration (OSN) is an emerging membrane separation technology, which urgently requires robust, easily processed, OSN membranes possessing high permeance and small solutes-selectivity to facilitate enhanced industrial uptake. Herein, we describe the use of two 2,2′-biphenol (BIPOL) derivatives to fabricate hyper-crosslinked, microporous polymer nanofilms through IP. Ultra-thin, defect-free polyesteramide/polyester nanofilms (≈5 nm) could be obtained readily due to the relatively large molecular size and ionized nature of the BIPOL monomers retarding the rate of the IP. The enhanced microporosity arises from the hyper-crosslinked network structure and monomer rigidity. Specifically, the amino-BIPOL/PAN membrane exhibits extraordinary permselectivity performances with molecular weight cut-off as low as 233 Da and MeOH permeance of ≈13 LMH/bar. Precise separation of small dye mixtures with similar M.W. based on both their charge and molecular size are achieved.

BACKGROUND: This study sought to investigate the effects of transversus thoracic muscle plane-pectoral nerves (TTP-PECS) block combined with propofol anesthesia on early perioperative pain sensitivity and cellular immune function in patients undergoing radical mastectomy. METHODS: A total of 115 patients who underwent radical mastectomy for breast cancer at our hospital from January 2019 to January 2021 were selected as the study subjects. The patients were allocated to the control group (n=57) or observation group (n=58) using a random number method. The control group was given simple general anesthesia, and the observation group was given TTP-PECS block combined with propofol anesthesia. The recovery time, pain [visual analogue scoring (VAS)] scores, and incidences of adverse reactions were compared between the 2 groups. Hemodynamic indicators [i.e., heart rate (HR), mean arterial pressure (MAP)], stress indicators [i.e., blood glucose (GLU), epinephrine (E), cortisol (Cor)], and the cellular immune function ofthe2 groups before anesthesia (T0), at the end of operation (T1), 1day after operation (T2) and 3days after operation (T3) were recorded. RESULTS: The spontaneous respiration recovery time, time to full wakefulness and the extubation time of the observation group were shorter than those of the control group (P0.05). The incidence of adverse reactions in the observation group was lower than that in the control group (8.62% vs. 24.56%) (P

In this study, hydrophilic halloysite nanotubes (HNTs) and poly (ethylene-co-vinyl alcohol) (EVOH) were mixed with hydrophobic polysulfone (PSF) in the presence of polyethylene glycol (PEG) to fabricate mixed matrix membranes (MMMs) free of macrovoids and enhanced performance via non-solvent induced phase separation (NIPS) technique. Various analytical techniques were used to probe the MMMs in terms of surface and cross-sectional morphology, functional groups, hydrophilicity, and mechanical strength. The separation and antifouling properties of PSF/EVOH/HNTs membranes were performed by bovine serum albumin (BSA) solution and gasoline (Oil) emulsion. The results showed delayed demixing and the formation of PSF/EVOH-MMMs with a spongy structure when the content of HNTs in the casting solutions was varied from 0.06–0.12 wt.%, owing to the formation of strong hydrogen bonds between PSF, EVOH, PEG and HNTs, which was confirmed by molecular dynamics (MD) simulations. The mechanical strength of the MMMs with 0.12 wt.% HNTs was increased 2.2-fold (up to 6.22 MPa), while the contact angle (CA) was the lowest at 47.42 ± 1.9°, indicating a significant increase in hydrophilicity. The underwater super oleophobic CA of the MMMs (169◦) also showed a 21% improvement over the pristine membrane (137◦). At the same time, the water permeability increased by a factor of 1.7 up to 419 L m− 2 h− 1 bar − 1 compared to the pristine membrane (0 wt.% HNTs) (246 L m− 2 h− 1 bar − 1). The rejection rates of MMMs (M12) for oil and BSA were > 90% and > 95%, respectively. After three cycles of fouling and cleaning experiments, the MMMs had > 90% flux recovery for both oil and BSA. In conclusion, this study demonstrates a new way to control the dope thermodynamics, formation dynamics, as well as morphology of MMMs by using the synergy of HNTs and polymers while maintaining promising properties for an improved separation performance of the UF membrane.

Polysulfone (PSF) is extensively used for the production of ultrafiltration (UF) membranes thanks to its high strength, chemical stability, and good processibility. However, PSF is intrinsically hydrophobic, and hydrophilic modification is always required to PSF-based membranes if they are intended to be used in aqueous systems. Facile strategies to prepare hydrophilic PSF membranes are thus highly demanded. Herein we spray coat a PSF-based amphiphilic block polymer onto macroporous substrates followed by selective swelling to prepare flat-sheet PSF UF membranes. The polymer is a triblock polymer containing PSF as the majority middle block tethered with shorter block of polyethylene glycol (PEG) on both ends, that is, PEG-b-PSF-b-PEG. We use the technique of spray coating to homogeneously dispense diluted triblock polymer solutions on the top of macroporous supports, instantly resulting in uniform, defect-free polymer coating layers with the thickness down to ~ 1.2 μm. The bi-layered composite structures are then immerged in ethanol/acetone mixture to generate mesoscale pores in the coating layers following the mechanism of selective swelling-induced pore generation, thus producing composite membranes with the mesoporous triblock polymer coating as the selective layers. This facile strategy is free from additional hydrophilic modification and much smaller dosages of polymers are used compared to conventional casting methods. The pore sizes, porosities, hydrophilicity, and consequently the separation properties of the membranes can be flexibly tuned by changing the swelling duration and the composition of the swelling bath. This strategy combining spray coating and selective swelling is upscalable for the production of high-performance PSF UF membranes.

Highly permeable organic solvent nanofiltration (OSN) membranes are desired to be used in an efficient and energy-saving chemical separation process. Herein, we fabricated a high-flux OSN membrane by synthesizing 7,7′-dihydroxy-2,2′-binaphthol (7,7′-OH-BINOL) as an aqueous phase monomer to react with trimesoyl chloride (TMC) via interfacial polymerization. The unique structures of 7,7′-OH-BINOL having a rotatable highly kinked unit and a rigid binaphthol ring endow the fabricated polyarylate membrane with very high microporosity and super-high Young's modulus. Both simulated and experimental results demonstrate that the BINOL-based polyarylate (PAR-BINOL) membrane has two types of micropores including cross-linked pores and stacked pores. Our results find that the PAR-BINOL membrane exhibits very high solvent permeance over a wide range of solvents with diverse polarity, and also possesses a long-term stable separation performance in solvents. Impressively, the membrane solvent permeance can reach up to 28.7 L m−2 h−1 bar−1, 9.2 L m−2 h−1 bar−1 and 6.7 L m−2 h−1 bar−1 for acetone, methanol, and dimethylformamide (DMF), respectively. The rejection of tetracycline (TC, Mw = 444 g mol−1) is 98.2%. Our work provides some insights into the molecular engineering of monomers with unique contorted and rigid structures for the fabrication of highly permeable OSN membranes.

Aromatic polyamide (PA) membranes fabricated from interfacial polymerization are widely used for desalination and water treatment. The fabrication of the high-flux PA membrane requires a fundamental understanding of the molecular mechanisms of water dynamics in the PA, which is still obscure due to the limited experimental methods. Herein, molecular dynamics (MD) simulations were employed to establish an atomic model of ultrathin free-standing PA membranes with various thickness and to explore the thickness-dependent dynamics of water molecules in the PA membrane. Simulation results illustrate that the simulated PA membrane has an average pore radius of 3 Å similar to the free volume size of the experimental PA membrane measured by PALS. The PA could be identified as the swelling layer (SL) and the confined layer (CL) based on their water diffusion rates. The diffusivity of water in the confined layer of PA membrane was much lower than that in the swelling layer and thus determined the water flux of the PA membrane. The water diffusivity in the sub-8 nm PA membrane is greatly enhanced due to a very thin confined layer thickness, illustrating the mechanism of the experimentally fabricated sub-8 nm PA membrane having the dramatically enhanced water permeability. Furthermore, results show that water molecules tend to transport rapidly in the free space inside the PA membrane. Our results provide some insights into the thickness-dependent water dynamics in the PA on a molecular level and may help to design the next generation of high-flux PA membranes.

In order to solve the problems of poor mechanical property, non-antibacterial and low flux of calcium alginate (CaAlg) membrane, silver nanoparticles (AgNPs) were synthesized with bovine serum albumin (BSA) and carboxymethyl chitosan (CMCS) for improving CaAlg membrane in this paper. Meanwhile, the dispersion property of silver nanoparticles and the mechanical property, thermal stability, antibacterial property and filtration efficiency of the composite membrane were explored. The results illustrated CMCS observably strengthened the mechanical property and thermal stability of the composite membrane, and AgNPs endowed the composite membrane with excellent antibacterial property. The flux of the BSA/CMCS/AgNPs/CaAlg composite membrane was raised compared to CaAlg membrane. Finally, the viscose fiber/polyethylene terephthalate fiber (VF-PET) nonwoven fabric was introduced as the support layer to further improve the filtration flux and mechanical property of the composite membrane. VF-PET/BSA/CMCS/AgNPs/CaAlg membrane had a rejection rate of over 99.0 % for dye molecules and9.0 % for salt ions, while the flux maintained 38.5 L·m

Tuning the optical and electrical properties of two-dimensional (2D) hexagonal boron nitride (hBN) is critical for its successful application in optoelectronics. Herein, we report a new methodology to significantly enhance the optoelectronic properties of hBN monolayers by substitutionally doping with sulfur (S) on a molten Au substrate using chemical vapor deposition. The S atoms are more geometrically and energetically favorable to be doped in the N sites than in the B sites of hBN, and the S 3p orbitals hybridize with the B 2p orbitals, forming a new conduction band edge that narrows its band gap. The band edge positions change with the doping concentration of S atoms. The conductivity increases up to 1.5 times and enhances the optoelectronic properties, compared to pristine hBN. A photodetector made of a 2D S-doped hBN film shows an extended wavelength response from 260 to 280 nm and a 50 times increase in its photocurrent and responsivity with light illumination at 280 nm. These enhancements are mainly due to the improved light absorption and increased electrical conductivity through doping with sulfur. This S-doped hBN monolayer film can be used in the next-generation electronics, optoelectronics, and spintronics.

The compact finite difference scheme is designed to numerically solve the nonlinear Schrodinger equation and coupled nonlinear Schrodinger equations on an unbounded domain in this paper. The original problem on an unbounded domain is reduced to an initial boundary value problem defined on a bounded computational domain by applying the artificial boundary method. Then, the reduced problem on the bounded computational domain is solved by an efficient semi-implicit compact finite difference scheme, which is a fourth-order scheme with respect to spatial variable. The scheme efficiently avoids the time-consuming iteration procedure necessary for the nonlinear scheme and thus is relatively time-saving. Finally, the stability of the proposed scheme is rigorously analyzed. Numerical examples are given to illustrate the accuracy and effectiveness of the proposed method.

Multilayer InSe is a promising material for high-performance optoelectronic applications because of its small direct band gap and good light absorption. However, as a photoconductive photodetector,...

Multilayer indium selenide (InSe) is a good candidate for high performance electronic and optoelectronic devices. The electrical performance of InSe is effectively regulated by dielectric layers, contact electrodes and surface doping. However, as a powerful tool to tune properties of materials, alloy engineering is absent for multilayer InSe. In this letter, for the first time, we investigate the electrical property of InSe1-xTex alloys and optoelectronic property of InSe-InSe0.82Te0.18p-n heterojunction. The electrical transport properties of InSe1-xTex alloys strongly depend on the content of Te composition. With the ratio of Te/Se increasing, the n-type electron transport behavior of InSe gradually transfers to the p-type hole transport behavior of InSe0.82Te0.18. The p-n InSe-InSe0.82Te0.18 heterojunction shows a rectification effect and a self-powered photodetection. The self-powered photodetector (SPPD) has a broad photodetection range from visible light (400 nm) to near-infrared (NIR) light (1000 nm). The responsivity (R) of SPPD is 14.1 mA/W under illuminated by NIR light (900 nm) at zero bias, which is comparable to some of the 2D heterojunctions NIR photodetectors measured with an external bias. The SPPD also shows a stable and fast response to NIR light (900 nm). This work demonstrates that the electrical transport properties of InSe1-xTex alloys significantly rely on the ratio of Te/Se and suggests that InSe-InSe1-xTex p-n heterojunction has a excellent potential for application in the self-powered optoelectronic device.

The reasonable design and synthesis of Co-based compounds with superior electrochemical activity and durability have aroused tremendous research interests. Herein, a simple molecular precursor pyrolysis strategy is proposed to fabricate Co4S3, Co9S8 nanoparticles hosted on reduced graphene oxide (rGO) sheets (Co4S3–Co9S8/C/rGO, CSG) using a GO-supported Co-coordination polymer as a precursor for the first time. The synthetic method has the advantages of simple operation and high repeatability. Well-dispersed Co4S3–Co9S8 nanoparticles and abundant interfaces maximize the amount of catalytically active sites. The synergistic adsorption of the reaction intermediates on the interface between Co4S3 and Co9S8 is propitious to electrochemical behavior. The rGO supports with high conductivity and enriched defects speed up the reaction kinetics and effectively inhibit the aggregation of cobalt sulfides. In an alkaline environment, the optimized CSG showed the lowest overpotential (134 mV) at 10 mA cm−2 among the studied materials for the hydrogen evolution reaction. In terms of Li-ion batteries, the hybrid composite CSG exhibited a remarkable reversible capacity of 814 mA h g−1 at a current density of 0.2 A g−1 after 200 cycles. Thus, the present design and engineering strategy may offer an idea for the preparation of other metal sulfides to boost electrochemical storage property.

In graphene-like 2D layered semiconductor-based field-effect transistors (FETs), the device performance is strongly influenced by a semiconductor–dielectric interface. In this study, it is demonstrated that a hybrid dielectric interface combines the advantages of high dielectric constant and inert polymer dielectric layer, and their synergistic effect induce the improvement of the InSe FET performance. A FET with a hybrid dielectric interface, composed of 200 nm PMMA and Hf0.5Zr0.5O2/Al2O3 (HZO/AlO), displays a mobility of 863 cm2 V−1 s−1, a relatively low sub-threshold swing of 462 mV dec−1, a diminutive hysteresis loop, an ultrahigh Ion–off ratio of ∼107, and low leakage current superior to the ones that use a conventional single dielectric layer. Experimental and theoretical results proved that the low density of charge trapping states and suppression of scattering effect at the semiconductor–dielectric interface synergistically result in enhanced device performances. The present study indicates that the smart combination of an inert polymer buffer layer and high-κ constant oxides is effective in optimizing the semiconductor–dielectric interface, and providing available interface engineering methods for other 2D materials.

different sand burial depths on seed germination, seedling emergence, growth and biomass allocation were studied to provide a scientific basis for further control of X. spinosum. Six sand burial depths (1, 2, 3, 5, 7 and 9 cm) were established to explore the response of X. spinosum seed germination and seedling growth to sand burial. The first emergence time, peak emergence time, emergence rate, seedling growth height, biomass and biomass distribution of X. spinosum seeds had significant effects at different sand burial depths (P < 0.05). The X. spinosum seeds had the highest emergence rate (71.5%) at 1 cm sand burial and the maximum seedling height (7.1 cm). As sand burial depth increased, the emergence rate and seedling height gradually decreased, and the emergence rate (12.25%) and seedling height (2.9 cm) were lowest at 9 cm sand burial. The root length at 9 cm depth (13.6 cm) was significantly higher than that at other sand depths (P < 0.05). The sand burial depth affected the biomass accumulation and distribution of X. spinosum. As sand burial depth increased, the root biomass and rhizome ratio increased, and the most deeply buried seedlings allocated more biomass for root growth. The optimal sand burial depth for seed germination and seedling growth of X. spinosum was 1–3 cm, and high burial depth (5–9 cm) was not conducive to the germination and growth of X. spinosum seedlings. For prevention and control of X. spinosum, we suggest deeply ploughing crops before sowing to ensure X. spinosum seeds are ploughed into a deep soil layer.

Our previous studies found that serum leptin was increased significantly in SLE, characterised by dysregulated autoreactive B cells producing excessive inflammatory cytokines and autoantibodies. The aim of this study was to explore the effects of leptin on B cell functions in SLE and clarify the key pathways in leptin dysregulated B cells.Peripheral blood samples were obtained from 86 SLE patients and 28 normal controls. Purified B cells were stimulated with leptin or SLE serum and with or without anti-leptin antibody. The frequencies of CD19-CD138+ plasma cells and the expression of leptin receptor (LEPR) on B cells were determined with flow cytometry. The levels of antibodies and cytokines were assayed by ELISA. Classic signalling pathways were detected with western blotting method.Increased plasma cells and the levels of IgG and anti-dsDNA antibodies were positively correlated with serum leptin in SLE patients. LEPR+CD19+B cells were increased in SLE patients. Leptin up-regulated LEPR on B cells and activated B cells to produce higher levels of IL-6, IL-10 and TNF-α, and induced B cells to differentiated into plasma cells secreting more IgG and IgM. More importantly, anti-leptin neutralising antibody could partially restore increased cytokines, antibodies and plasma cells induced by SLE serum. Mechanistically, both leptin and SLE serum activated JAK/STAT3/5 and ERK1/2 signalling pathways in B cells, and the secretion-enhancing effects were restored by their inhibitors.Leptin may be a key factor leading to B cell dysfunction by activating JAK/STAT3/5 and ERK1/2 signalling pathways in SLE.

BACKGROUND: To explore the effects of ultrasound-guided erector spinae plane (ESP) block on the immune function and postoperative recovery of patients undergoing radical mastectomy. METHODS: One hundred and four patients with breast cancer were randomly divided into the observation group and control group, with 52 cases in each group. The control group underwent induction of routine general anesthesia and thoracic paravertebral block, while the observation group underwent ultrasound-guided ESP block combined with general anesthesia. The recovery of autonomous respiration, eye opening, extubation time, postoperative eating, first anal exhaust, leaving bed and hospitalization time in both groups were statistically analyzed after surgery. The immune function indexes [CD4+, CD8+, interferon-γ (IFN-γ)] and the expression levels of serum neuropeptide Y (NPY), prostaglandin E2 (PGE2) and serotonin (5-HT) were compared between the two groups at 24 and 48 h before and after surgery. The visual analog scale (VAS) scores at rest and during exercise were recorded at 6, 12, 24, and 48 h after surgery. RESULTS: There was no significant difference in the recovery of autonomous respiration, eye opening, and extubation time between the two groups (P>0.05). However, postoperative eating, first anal exhaust, leaving bed, and hospitalization time in the observation group were shorter than those in the control group (P

The monolayer MoS

Biomimetic eyes, with their excellent imaging functions such as large fields of view and low aberrations, have shown great potentials in the fields of visual prostheses and robotics. However, high power consumption and difficulties in device integration severely restrict their rapid development. In this study, an artificial synaptic device consisting of a molybdenum disulfide (MoS

Self-powered photodetectors have attracted widespread attention due to their low power consumption which can be driven by the built-in electric field instead of external power, but it is very difficult to achieve high responsivity and fast response speed concurrently. Here, a self-powered photodetector with light-induced electric field enhancement based on a 2D InSe/WSe