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Vertical strain and external electric field can regulate interfacial charge transfer, resulting in the tunable Schottky barriers of G/XAu4Y heterostructures.

In order to ensure the safety of deep-sea submarine pipelines, this paper focuses on the analysis of the axial temperature distribution model of the submarine pipeline and the distribution parameter circuit model of the tube bundle heating system. Combined with these two models, theoretical analysis shows that the heating effect of the tube bundle heating system depends on the distributed circuit parameters and power frequency of the system. In order to improve the heat tracing efficiency, the power frequency needs to be adjusted according to the change of the load temperature, so the power supply frequency of the tube bundle heating system based on the Hammerstein model is optimized. Using a neuro-fuzzy algorithm, not only the theoretical values of heating power and power frequency are obtained, but also the drawbacks of determining the above parameters based on engineering experiments are avoided. Moreover, the pipeline heating is efficient and stable, the dynamic response is fast, and the working condition is also well adapted.

To analyze the effects of sodium hyaluronate combined with recombinant human epidermal growth factor (rhEGF) eye drops in patients with dry eye. Totally 97 patients who suffered dry eye after cataract surgery in our hospital from March 2018 to June 2020 were selected and randomly assigned into control group (n=57, sodium hyaluronate eye drops) and intervention group (n=63, sodium hyaluronate combined with rhEGF eye drops). The clinical efficacy, Break Up Time (BUT), schirmer I test (SLt), fluorescent test (FL) and ocular surface disease index (OSDI), the scale of quality of life for disease with visual impairment (SQOL-DVI), interleukin-6 (IL-6), tumor necrosis factor (TNF-a) level of the two groups were compared. The intervention group yielded remarkably higher effective rate than the control group (p0.05). Markedly higher BUT, SLt, SQOL-DVI scores and lower OSDI scores were witnessed among patients in the intervention group than the control group (p0.05). The clinical effect of sodium hyaluronate combined with rhEGF eye drops in the treatment of dry eye is superior to sodium hyaluronate alone, in terms of enhancing the stability of tear film, accelerating corneal healing, inhibiting the level of inflammatory factors and improving patients' quality of life.

Highly-active and durable electrocatalysts are highly important for electrochemical energy conversion devices. Herein, we report the design and fabrication of PtCo bimetallic nanoparticles encapsulated in N-doped carbon nanorod arrays (PtCo@N C) on carbon cloth as an integrated binder-free catalyst for both methanol oxidation reaction (MOR) and hydrogen evolution reaction (HER). The unique structural advantage and bimetallic synergetic effect of such composite catalyst provide a high specific surface area and abundant electrochemical active sites for the electrocatalysis process. As a result, the as-obtained PtCo@N C with optimized Pt loading exhibit significantly improved methanol electro-oxidation performance in terms of high areal activity of 2.17 mA cm−2, superior CO tolerance and reliable stability in contrast to that of commercial Pt/C catalysts. In addition, the PtCo@N C catalyst also shows promising electrocatalytic activity with small onset potential of 12 mV vs RHE, low Tafel slope of 48 mV dec−1 as well as excellent long-term stability for HER.

AimsTo compare the efficacy of compression sutures combined with intracameral air injection (CSAI) and thermokeratoplasty (TKP) for the management of acute corneal hydrops in keratoconus.MethodsIn this multi-centre randomised clinical trial, 20 patients with keratoconus (20 eyes) with acute corneal hydrops were enrolled and randomised to receive either CSAI or TKP and followed-up for a period of 6 months.ResultsThere were no significant differences in patient demographics, severity of corneal hydrops and preoperative duration of symptoms between the two groups. In both groups, corneal oedema resolved within 2 weeks. The maximum thickness of the corneal scars following CSAI and TKP was not significantly different. Best spectacle-corrected visual acuity was superior in the CSAI group at 6-month follow-up (CSAI vs TKP, 0.52 (0.37, 0.85) vs 0.96 (0.70, 1.34) LogMAR, p=0.042). CSAI resulted in greater corneal endothelial cell density (CSAI vs TKP, 2677.8±326.7 vs 1955.3±298.1 cells/mm2, pConclusionAlthough both CSAI and TKP resulted in resolution of acute corneal hydrops in keratoconus, CSAI was associated with superior clinical outcomes in this study.Chinese Clinical trial registration numberChiCTR-IOR-17013764

Earth-abundant electrocatalysts for both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in a wide pH range are highly desirable for sustainable energy conversion technologies, but challenging to develop. Herein, we report hollow CoP nanosphere-embedded carbon nanotube/nitrogen-doped carbon (NC-CNT/CoP) nanoarrays, in which a nanoscale Kirkendall effect generates few-layer graphene-coated hollow CoP nanospheres with abundant active sites. The integrated NC-CNT/CoP electrode behaves as an efficient pH-universal HER catalyst and, through in situ transformation, the derived materials show excellent OER performance. The NC-CNT/CoP-based electrolyzers achieve a current density of 10 mA cm−2 at low voltages of 1.63, 1.69, and 1.66 V in KOH, PBS, and H2SO4, respectively, which are similar to the values obtained using noble metal catalysts. Importantly, the integrated electrode exhibits superior stability than that of the benchmark noble metals in a wide pH range. This work presents a promising method for achieving nonprecious catalysts for efficient energy conversion.

We report a facile strategy to prepare carbon nanotubes embedded with hollow CoP nanoparticles arrays (H-CoP-NPs@CNTs) on flexible carbon cloth through hydrothermal synthesis, carbothermal reduction and phosphorization. The unique H-CoP-NPs@CNTs as free-standing sodium ion battery anodes exhibit remarkable electrochemical performances a specific capacity of 965.6 mA h g−1 for the 1st cycle and 63% retained capacity after rates test and 100 cycles at 100 mA g-1. The capacity retention rate is as high as 94.3% after different current sweeps. The excellent electrochemical performance can be attributed to the unique 1D hybrids nanoarrays structures, in which the pore inside and between hollow CoP nanoparticles provide more free spaces and active sites for favorable Na+ insertion/extraction, and the CNTs nanoarrays on flexible carbon cloth are able to improve the conductivity and maintain the structural integrity. Moreover, the 1D hybrids network also makes it favorable rapid ion/electron transport and enhanced rate performance.

Two-dimensional metal-semiconductor heterostructures with tunable Schottky barriers are currently attracting extensive interests, owing to their novel properties and potential applications in nanodevices. Here, heterostructures of semiconducting monolayer gold sulfides and graphene (Gr) with tunable Schottky barriers and contact types are reported based on first-principles calculations. α-, β-Au2S/Gr are n-type Schottky contacts with Φ n = 0.14 eV and 1.24 eV, respectively. They could be transformed into p-type Schottky contacts via applying vertically compressive strain. α-, β-, γ-AuS/Gr are ohmic, p-type and n-type Schottky contacts with Φ n = −0.34 eV, Φ p = 0.22 eV, Φ n = 0.22 eV, respectively. The ohmic contact of α-AuS/Gr evolves to a n-type Schottky contact with increasing vertically compressive strain, while the p-type Schottky contact of β-AuS/Gr changes to an ohmic contact. Furthermore, the mechanism of Schottky-barrier modulation via vertical strain underlies that the relative Dirac-cone position of Gr in heterostructures can be tuned by adjusting interfacial charge rearrangement. Benefitting from the tunable Schottky barriers and contact types, heterostructures of semiconducting monolayer gold sulfides and Gr are promising candidates for future-generation nano-devices.

Two-dimensional (2D) MoS 2 has been considered as a potential catalyst in hydrogen evolution reaction (HER), but its catalytic reactions usually only occur at the active edge sites rather than the inert surfaces. In this work, we propose a strategy to enhance the catalytic activity of MoS 2 by decorating the inert surfaces of MoS 2 nanosheets with ultrafine Pt nanoparticles through an atomic layer deposition (ALD) technique. The optimized Pt/MoS 2 catalyst with ultralow Pt mass loading (∼2.2 wt%) presents exceptional HER performances in terms of low onset overpotential (31 mV), small Tafel slope (52 mV dec −1 ) and firm HER durability, which is comparable to the commercial Pt/C catalyst.

We report a novel three-dimensional (3D) cabon@Fe2O3@SnO2 hierarchical composite inverse opals arrays electrode for binder-free Li-ion battery anode. In this electrode design, the ordered macroporous SnO2 acts as conductive skeletons for supporting the 1D Fe2O3 nanorods, offering a high specific surface area and fast pathways for both electron and ion transport, while the carbon coated on the Fe2O3 surfaces works as a buffer layer to improve the conductivity and structural stability. Benefiting from this smart design, the hierarchical carbon@Fe2O3@SnO2 composite inverse opals electrode as a Li ion battery anode exhibits a high discharge capacity of 1021 mAh/g at a current density of 100 mA/g, better cycling life (capacity retaining at 388 mAh/g after 200 cycles) and excellent rate capability, which is superior to those of individual SnO2 inverse opals and SnO2@Fe2O3 inverse opals electrodes.

Highly active and durable electrocatalysts are highly desirable for electrochemical energy conversion devices. Herein, we report the design and fabrication of Pt nanoplate decorated 3D vertical graphene nanosheet arrays supported on carbon cloth (Pt-VGNSAs/CC) as an integrated binder-free catalyst for both methanol oxidation and hydrogen evolution reactions (HER). The vertically aligned graphene nanosheets with large surface area and excellent conductivity provide an ideal support for dispersing the Pt nanoplates. As a result, the as-obtained Pt-VGNSAs/CC with optimized Pt loading exhibits significantly improved methanol electro-oxidation performance in terms of a high mass activity of 1050 mA mg−1 and areal activity of 1.45 mA cm−2, superior CO tolerance and reliable stability in contrast to those of commercial Pt/C catalysts. In addition, the Pt-VGNSAs/CC catalyst also shows promising electrocatalytic activity with a small onset potential of −60 mV vs. the RHE at 10 mA cm−2, and a low Tafel slope of 28.5 mV dec−1 as well as excellent long-term stability for the HER. The significantly enhanced electrocatalytic performance could be attributed to the structural advantages and strong synergistic effects between graphene and Pt.

In coal-bed methane (CBM) reservoirs, gas is mainly stored in matrix as adsorbed gas and the cleats are commonly saturated with water. To produce the adsorbed gas, the cleat pressure should be reduced to critical desorption pressure by dewatering first. But how to dewater more efficiently is a difficult issue. Apparently low dewatering rate is uneconomical due to excessive development times required. But from the field experiences, high dewatering rate will bring more problems such as coal break, stress sensitivity and two-phase flow in earliest stage, which will reduce the productivity, or sometimes make the well abandoned. Literatures have studied much about the effect of coal break and stress sensitivity. However, there is no discussion about the relationship between two-phase flow and dewatering rate. High dewatering rate is companied with high pressure drawdown which will cause gas desorption near wellbore area and simultaneously cause two-phase flow. Two-phase flow has significant negative effect on pressure propagation, which controls investigation distance or drainage area in the early stage, and therefore affects the overall productivity. Since the purpose of dewatering is to maximize the drainage area and maximize the depressurization for whole reservoir, the dewatering rate should be controlled to ensure well-bottom hole flowing pressure (BHFP) is larger than critical desorption pressure in order to avoid the occurrence of two-phase flow in the dewatering stage. Based on this principle, a procedure for optimal dewatering rate is presented and a mathematic model is established. It is shown that initial pressure, critical desorption pressure, permeability, porosity, and fracture half-length play significant roles in dewatering rate determination. This method is easy, and has applied in CBM development region of Han-Cheng, China.

We report the fabrication of 3D flower-like MoS2 nanosheets arrays on carbon cloth as a binder-free anode for sodium ion battery. Ultrathin and conformal TiO2 layers are used to modify the surface of MoS2 by atomic layer deposition. The electrochemical performance measurements demonstrate that the ALD TiO2 layer can improve the cycling stability and rate capability of MoS2. The MoS2 nanosheets with 0.5-nm TiO2 coating electrode show the highest initial discharge capacity of 1392 mA h g–1 at 200 mA g–1, which is increased by 53% compared with that of bare MoS2. After 150 cycles, the capacity retention rate of the TiO2-coated MoS2 achieves 75.8% of its second cycle’s capacity at 200 mA h g–1 in contrast to that of 59% of pure MoS2. Furthermore, the mechanism behind the experimental results is revealed by ex situ scanning electron microscope (SEM), X-ray powder diffraction (XRD), and electrochemical impedance spectroscopy (EIS) characterizations, which confirms that the ultrathin TiO2 modifications can preve...

Highly active and durable air cathodes to catalyze both the oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) are urgently required for rechargeable metal-air batteries. In this work, an efficient bifunctional oxygen catalyst comprising hollow Co

Purpose: The purpose of this study was to analyze the relationship between corneal opacity and vision acuity in patientswith cataracts and coexisting corneal opacity by calculating the area of corneal opacities in the optical zone. Methods: This retrospective study involved 177 cataract patients (184 eyes) with corneal opacity who were successfullyundergoing manual, small-incision cataract extraction and intraocular lens implantation. These patients were all treated bythe same surgeon from December, 2011 to March, 2014 in our hospital. The 184 eyes analyzed were divided into threegroups according to the area of corneal opacity in optical zone (O/OZ): Group 1: O/OZ < 30%, Group 2: 30% ≤ O/OZ< 60%, Group 3: O/OZ ≥ 60%. Results: Preoperative visual acuity of all 184 eyes examined was less than 20/70. Postoperative visual acuity differed significantlybetween the three groups. O/OZ was significantly correlated with preoperative visual acuity and visual acuityimprovement (P = 0.001, P = 0.039). When O/OZ < 60%, postoperative visual acuity was associated with hardness of thelens nucleus. When O/OZ ≥ 60%, visual acuity depended on the area of corneal opacity rather than the hardness of thenucleus. Conclusion: Findings from this study demonstrate that manual small-incision cataract extraction and intraocular lens implantationfor patients with cataract coexisting corneal opacity is feasible and safe. Visual acuity was significantly correlatedwith both O/OZ and lens opacity.

A three-dimensional dandelion-like Li4Ti5O12@graphene microsphere electrode is designed by using a simple and scalable solution fabrication process. The graphene nanosheets are incorporated into the porous dandelion-like Li4Ti5O12 microspheres homogenously, which provide a highly conductive network for electron transportation. When tested as an anode for Li-ion batteries, the dandelion-like Li4Ti5O12@graphene composite with 3 wt% graphene exhibits excellent rate capabilities and superior cycle life between 0.01 and 3.0 V. The capacities of Li4Ti5O12@graphene (3 wt%) reach 206 mA h g−1 after 500 cycles between 0.01 and 3.0 V and 166 mA h g−1 after 100 cycles between 0.7 and 3.0 V at a current density of 0.12 A g−1, respectively. In addition, Li4Ti5O12-based anode materials at lower voltage can offer a higher cell voltage and discharge capacity for lithium-ion batteries. Hence, it is significant to study the electrochemical behaviors of the Li4Ti5O12-based anode in a wide voltage range of 0.01–3.0 V. This facile and scalable method for Li4Ti5O12@graphene composites represents an effective strategy to develop advanced electrochemical energy storage systems with long cycle life and high rate performance.

With the development of flexible electronic devices, the research on flexible storage devices has received considerable attention. In this paper, we designed novel tin nanoparticles encapsulated in carbon nanotubes (TNEC) arrays on carbon cloth prepared by a facile carbon reduction route as a flexible anode for lithium-ion batteries. The TNEC electrode shows a high areal capacity (2.15 mAh cm−2) when the current density is 0.1 mA cm−2, Meanwhile, a good cycling performance (84 % of initial capacity) is achieved after 80 charge–discharge cycles, which could be attributed to the high theoretical capacity of metal tin and the tin encapsulated in carbon nanotubes structure that improves the electrical conductivity and structure stability.

A novel photoanode of 3D TiO2/SnO2 hierarchically branched nanowires on transparent FTO glass substrate with SnO2 nanowires as backbones and TiO2 nanorods as branches is fabricated by a combination of chemical vapor deposition and hydrothermal growth process. PEC device constructed by using this hierarchical architecture presents excellent performance with a maximum photocurrent density of 1 mA cm−2, which is 5 times larger than that of TiO2/SnO2 core–shell nanowires. The greatly improved PEC performance is due to the 3D hierarchically branched structural effect, as result of enhancing the surface area as well as improvement of light harnessing and charge collection efficiency.

In this paper, a highly ordered three-dimensional Co3O4@MnO2 hierarchical porous nanoneedle array on nickel foam is fabricated by a facile, stepwise hydrothermal approach. The morphologies evolution of Co3O4 and Co3O4@MnO2 nanostructures upon reaction times and growth temperature are investigated in detail. Moreover, the as-prepared Co3O4@MnO2 hierarchical structures are investigated as anodes for both supercapacitors and Li-ion batteries. When used for supercapacitors, excellent electrochemical performances such as high specific capacitances of 932.8 F g−1 at a scan rate of 10 mV s−1 and 1693.2 F g−1 at a current density of 1 A g−1 as well as long-term cycling stability and high energy density (66.2 W h kg−1 at a power density of 0.25 kW kg−1), which are better than that of the individual component of Co3O4 nanoneedles and MnO2 nanosheets, are obtained. The Co3O4@MnO2 NAs are also tested as anode material for LIBs for the first time, which presents an improved performance with high reversible capacity of 1060 mA h g−1 at a rate of 120 mA g−1, good cycling stability, and rate capability.

We report the fabrication of 3D flower-like MoS

We report a 3D ordered urchin-like hollow TiO2/ZnO nanorods structure on transparent FTO substrates that serves as photoanode for efficient photoelectrochemical anode. The ordered urchin-like TiO2/ZnO structure is prepared by a combination of colloidal spheres template, atomic layer deposition and hydrothermal growth method. Under simulated sunlight illumination, the CdS sensitized urchin-like TiO2/ZnO photoanode generates a photocurrent of 3.6 mA cm−2 at 0 V vs Ag/AgCl, which is higher than that of either 2D TiO2/ZnO inverse opals or 1D ZnO nanowire arrays, due to its 3D structural advantages that offers higher surface area for quantum dots loading plus enhanced light scattering ability.

Most coal seams are characterized by an anisotropic network of cleat system in which continuous face cleats have much more permeability than discontinuous butt cleats. In hydraulically fractured and anisotropic CBM reservoirs, pressure propagation and resulting drainage area is in elliptical geometry. The determination of optimal well pattern and well spacing in such a system is the key parameter for higher well productivity and optimized CBM field development plan. In this study, well pattern and well spacing in anisotropic CBM reservoirs with fractured wells are optimized based on the concept of balanced depressurization which is assumed that the reservoir pressure should be declined uniformly in all directions of drainage area. The mathematical relationship for optimal well spacing is first developed and is verified by numerical simulation. It is concluded that, based on the requirement of balanced depressurization, the rectangular or diamond shaped pattern is the best pattern for hydraulically-fractured anisotropic coal seams, and the optimal well spacing is determined by both permeability ratio and hydraulic fracture length. Furthermore, a procedure for optimization of CBM well pattern and spacing is presented for making development strategy.

The accident of drilling blowout out of control is a serious drilling accident. One of the measures that prevent this accident is detecting gas kick early. Mud pool liquid level method is one of the most widely used methods. But, due to the drilling bell mouth is exposed to the atmosphere, drilling fluid in the return pipe flow is not a full pipe flow but a free flow. When the gas kick was tiny, the change of mud pool level is unobvious and Liquid level detection device could not measure the level changes effectually. Drilling fluid return flow can’t be measured, and the error was so great that can’t detect the gas kick early. Air and drilling fluid (non-Newtonian fluid) were taken as mediums, to simulate the drilling fluid liquid level when drilling fluid return flow changed based on the Volume of Fluid multiphase flow model, then the characteristic of liquid level change in the return pipeline was analyzed with different gas rate in drilling fluid. It concluded that the liquid level in the bell mouth was changing obviously, when the drilling fluid has been changed with none gas. Give a suggest that Liquid level detection should be installed on the bell mouth in drilling fluid return pipe in order to find gas kick more accurately and effectively earlier. The gas kick rate has a great impact on the stability of the drilling fluid liquid level in the return pipeline.

PURPOSE To evaluate the long-term outcomes of deep anterior lamellar keratoplasty for the management of deep stromal corneal opacities after herpes simplex keratitis (HSK) infection. METHODS Case records of patients who underwent deep anterior lamellar keratoplasty between January 2006 and June 2012 to treat HSK-related deep stromal corneal scars were retrospectively analyzed. The cases were divided into folds-on, folds-off, and no-folds groups based on the presence of stromal folds intraoperatively. The main outcome measures were best-corrected visual acuity, endothelial cell density, and complications. RESULTS A total of 89 patients (89 eyes; 54 men and 35 women; 47.1 ± 12.9 years old) were included. Based on intraoperative events, 48 eyes had no stromal folds, 27 eyes had folds that were centrally peeled off, and 14 eyes had folds that could not be peeled. The average follow-up period was 50.4 ± 12.7 months. The mean best-corrected visual acuity improved from 1.63 ± 60.52 logMAR preoperatively to 0.44 ± 0.31 logMAR at the last visit (P < 0.001). Mean postoperative endothelial cell density was 1738 ± 573 cells per square millimeter. Eight eyes experienced HSK recurrence, 3 eyes had an episode of stromal rejection, and 3 eyes developed corneal endothelial decompensation. Cases in the folds-off group had a significantly higher rate of Descemet membrane microperforations compared with the other groups. CONCLUSIONS Deep anterior lamellar keratoplasty is a viable alternative for the management of HSK-related deep stromal opacity. Although posterior corneal folds can be relieved intraoperatively in some of these cases, folds near Descemet membrane should be left in situ because of the high risk of Descemet membrane perforation.

The red alga, Furcellaria lumbricalis from the coast of the Prince Edward Island (PEI) in Atlantic Canada, was extracted with hot water and fractionated with 0.125. M KCl to obtain a carrageenan-like polysaccharide. The polysaccharide was further purified on ion-exchange and gel-permeation chromatography to yield a fraction (FB1) of uniform size and charge, with an average molecular weight of 428. kD. Oligosaccharides generated with acid hydrolysis of FB1 were sequenced using the electrospray ionisation collision induced dissociation tandem mass spectrometry (ES-CID-MS/MS) technique. On the basis of chemical and spectroscopic analysis, FB1 was characterised to be composed of 1,4-linked 3,6-anhydro-galactose (40%), 1,3-linked 4-sulphated-galactose (30%), 1,3-linked galactose (20%), 1,4-linked galactose (8%) and 1,4-linked 3-O-methyl-galactose (2%), which makes it be a novel sulphated galactan hybrid. The I²-secretase (BACE) inhibition and immunomodulation activities of FB1-derived oligosaccharides were evaluated in vitro.

In this article, we report a novel electrode of NiCo2O4 nanowire arrays (NWAs) on carbon textiles with a polypyrrole (PPy) nanosphere shell layer to enhance the pseudocapacitive performance. The merits of highly conductive PPy and short ion transport channels in ordered NiCo2O4 mesoporous nanowire arrays together with the synergistic effect between NiCo2O4 and PPy result in a high specific capacitance of 2244 F g(-1), excellent rate capability, and cycling stability in NiCo2O4/PPy electrode. Moreover, a lightweight and flexible asymmetric supercapacitor (ASC) device is successfully assembled using the hybrid NiCo2O4@PPy NWAs and activated carbon (AC) as electrodes, achieving high energy density (58.8 W h kg(-1) at 365 W kg(-1)), outstanding power density (10.2 kW kg(-1) at 28.4 W h kg(-1)) and excellent cycling stability (∼89.2% retention after 5000 cycles), as well as high flexibility. The three-dimensional coaxial architecture design opens up new opportunities to fabricate a high-performance flexible supercapacitor for future portable and wearable electronic devices.

In this study, three-dimensional SnO2@TiO2 double-shell nanotubes on carbon cloth are synthesized by a combination of the hydrothermal method for ZnO nanorods and a subsequent SnO2 and TiO2 thin film coating with atomic layer deposition (ALD). The as-prepared SnO2@TiO2 double-shell nanotubes are further tested as a flexible anode for Li ion batteries. The SnO2@TiO2 double-shell nanotubes/carbon cloth electrode exhibited a high initial discharge capacity (e.g. 778.8 mA h g(-1) at a high current density of 780 mA g(-1)) and good cycling performance, which could be attributed to the 3D double-layer nanotube structure. The interior space of the stable TiO2 hollow tube can accommodate the large internal stress caused by volume expansion of SnO2 and protect SnO2 from pulverization and exfoliation.

The self-assembled monolayer periodic array of polystyrene spheres conformally coated with TiO2 layer using atomic layer deposition is designed to obtain a further enhancement of light extraction for LYSO scintillator. The maximum enhancement is 149% for the sample with polystyrene spheres conformally coated with TiO2 layer, while the enhancement is only 76% for the sample with only polystyrene spheres. Such further enhancement could be contributed from the additional modes forming by TiO2 layer due to its high refractive index, which can be approved by the simulation of electric field distribution. The experimental results are agreement with the simulated results. Furthermore, the prepared structured layer exhibits an excellent combination with the surface of scintillator, which is in favor of the practical application. Therefore, it is safely concluded that the combination of self-assembly method and atomic layer deposition is a promising approach to obtain a significant enhancement of light extraction for a large area. This method can be extended to many other luminescent materials and devices.

As people in different rooms usually have different thermal comfort feelings or demands, it is valuable to study the modeling and control of thermal comfort to meet the personalized requirements. This paper tries to solve this issue using the data collected by the temperature and humidity sensors in the working or living time periods in the room being studied. We firstly present a statistic method based sensor data preprocessing strategy to discard noisy data and obtain the reasonable intervals for the temperature and humidity of each day. Then, we construct the Gaussian interval type-2 fuzzy set models to depict the personalized temperature and humidity comfort through measuring the uncertainty degrees of the obtained intervals. At last, we propose a control scheme to realize the personalized thermal comfort regulation. Our results show that the constructed thermal comfort models can recommend a reasonable temperature and humidity range for the demand in a specific room.

Highly active and durable air cathodes to catalyze both the oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) are urgently required for rechargeable metal-air batteries. In this work, an efficient bifunctional oxygen catalyst comprising hollow Co3 O4 nanospheres embedded in nitrogen-doped carbon nanowall arrays on flexible carbon cloth (NC-Co3 O4 /CC) is reported. The hierarchical structure is facilely derived from a metal-organic framework precursor. A carbon onion coating constrains the Kirkendall effect to promote the conversion of the Co nanoparticles into irregular hollow oxide nanospheres with a fine scale nanograin structure, which enables promising catalytic properties toward both OER and ORR. The integrated NC-Co3 O4 /CC can be used as an additive-free air cathode for flexible all-solid-state zinc-air batteries, which present high open circuit potential (1.44 V), high capacity (387.2 mAh g-1 , based on the total mass of Zn and catalysts), excellent cycling stability and mechanical flexibility, significantly outperforming Pt- and Ir-based zinc-air batteries.

This study reports the design and fabrication of ultrathin MoS2 nanosheets@metal organic framework-derived N-doped carbon nanowall array hybrids on flexible carbon cloth (CC@CN@MoS2) as a free-standing anode for high-performance sodium ion batteries. When evaluated as an anode for sodium ion battery, the as-fabricated CC@CN@MoS2 electrode exhibits a high capacity (653.9 mA h g−1 of the second cycle and 619.2 mA h g−1 after 100 cycles at 200 mA g−1), excellent rate capability, and long cycling life stability (265 mA h g−1 at 1 A g−1 after 1000 cycles). The excellent electrochemical performance can be attributed to the unique 2D hybrid structures, in which the ultrathin MoS2 nanosheets with expanded interlayers can provide shortened ion diffusion paths and favorable Na+ insertion/extraction space, and the porous N-doped carbon nanowall arrays on flexible carbon cloth are able to improve the conductivity and maintain the structural integrity. Moreover, the N-doping-induced defects also make them favorable for the effective storage of sodium ions, which enables the enhanced capacity and rate performance of MoS2.

Metal-organic frameworks (MOFs) are promising porous precursors for the construction of various functional materials for high-performance electrochemical energy storage and conversion. Herein, a facile two-step solution method to rational design of a novel electrode of hollow NiCo2O4 nanowall arrays on flexible carbon cloth substrate is reported. Uniform 2D cobalt-based wall-like MOFs are first synthesized via a solution reaction, and then the 2D solid nanowall arrays are converted into hollow and porous NiCo2O4 nanostructures through an ion-exchange and etching process with an additional annealing treatment. The as-obtained NiCo2O4 nanostructure arrays can provide rich reaction sites and short ion diffusion path. When evaluated as a flexible electrode material for supercapacitor, the as-fabricated NiCo2O4 nanowall electrode shows remarkable electrochemical performance with excellent rate capability and long cycle life. In addition, the hollow NiCo2O4 nanowall electrode exhibits promising electrocatalytic activity for oxygen evolution reaction. This work provides an example of rational design of hollow nanostructured metal oxide arrays with high electrochemical performance and mechanical flexibility, holding great potential for future flexible multifunctional electronic devices.