As a kind of nanotechnology, nanomaterials have made great progress in recent years, among which nanotube is one of the most representative new nanomaterials. Knee arthritis, as a degenerative bone ...disease, often occurs in the elderly. According to statistics, the incidence of knee arthritis in China is between 3 and 15 percent, among which the incidence of the elderly over 65 years old is as high as 68 percent. The purpose of this study is to explore the application effect of the rehabilitation therapy of nanotube combined with roller skater in the treatment of knee arthritis and promote the continuous improvement of clinical treatment effect of knee joint. In this study, by comparing the curative effect of the roller skates combined with nanotubes in the rehabilitation treatment group and the control group, the clinical treatment effects of the two groups were comprehensively evaluated and evaluating the comprehensive effects of nanotubes combined with roller skates from various angles of a comprehensive role of rehabilitation therapy in the treatment of knee osteoarthritis, to give full play to the advantages of nanotubes and rehabilitation therapy, promote the continuous improvement of treatment, and provide important guidance for the clinical treatment of knee arthritis, thereby improving the therapeutic effect. The results showed that the total effective dose was 82.61% in the control group and 97.83% in the observation group. Before and after the treatment, the therapeutic effect of the nanotube drug treatment group was improved by about 40%, and the therapeutic effect of the observation group of rehabilitation therapy with nanotube combined wheel athletes was increased by about 42%. It indicates that compared with the single treatment, the rehabilitation therapy of the nanotube combined with roller skater greatly improves the therapeutic effect of knee arthritis.
Covalent organic frameworks (COFs) are regarded as important candidates for the preparation of advanced membranes with remarkable performances on account of their uniform and tailorable channels and ...good chemical stability. The development of COFs-based membranes is burgeoning, and there remains lacking of facile and mild methods to prepare to these membranes. Herein, we report on the unidirectional diffusion synthesis (UDS) of TpPa (an imine-based COFs) on commercial polyvinylidene fluoride (PVDF) microfiltration substrates for the preparation of composite COFs-based membranes at room temperature. The p-phenylenediamine (Pa) aqueous solution and 1,3,5-triformylphloroglucinol (Tp) n-hexane solution were separately charged into the two sides of a diffusion cell. With the suitable solution pairs and molar ratio of two precursors, only Pa molecules can pass through the macropores of PVDF to react with Tp molecules at the phase interface formed by this solution pairs, leading to the in situ synthesis of TpPa layer on the top side of PVDF substrates. The membrane fabricated with a synthesized duration of 24 h exhibits a superior selectivity for dyes (>90%) and appreciable water permeance (60 L·m−2·h−1·bar−1). The permeance of the resultant membrane is ∼2–20 times higher than other reported membranes with comparable dye rejections. The UDS offers a facile and mild process to directly grow COFs on porous polymeric substrates to construct composite membranes capable of efficient separations of dye molecules.
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•COF membranes have been directly synthesized on PVDF substrates by UDS.•The performances of TpPa/PVDF membranes can be easily tuned by reaction durations.•The membranes exhibit a high rejection to dye with size above 1.1 nm from water.•The membranes present good long-term stability and excellent chemical stability.
By establishing a two-stage model in which a monopolization firm first chooses R&D input and then the quantity of energy, this paper compares the different effects of two regulatory policies: feed-in ...tariff (FIT) and renewable portfolio standard (PRS). The results show that FIT is more efficient than RPS to increase the quantity of renewable energy (installed capacity) and to stimulate the R&D input to reduce costs. And RPS policy is more efficient to reduce the carbon emissions and to improve the consumer surplus. Apart from existing findings, we cannot obtain the accurate conclusion about the effects of social welfare under the two policies. The effects of two policies on the social welfare heavily depend on the level of negative externality.
•We compare the different effects of two regulatory policies: FIT and PRS.•FIT is more efficient than RPS to increase renewable-energy quantity and to stimulate R&D.•RPS is more efficient to reduce the carbon emissions and to improve the consumer surplus.•The effects of two policies on the social welfare depend on the level of negative externality.
Y3Al5O12:Ce3+ (YAG:Ce3+) transparent ceramic phosphors (TCPs) are regarded as the most promising luminescent converter for laser‐driven (LD) lighting. High‐quality YAG:Ce3+ TCPs are still urgent for ...high efficiency LD lighting devices. YAG:Ce3+ TCPs in a vacuum ambience by using nano‐sized raw materials are prepared. Controlling defects by adding nano‐sized MgO and SiO2 simultaneously enables a high transmittance nearly 80%. After annealing in air furthermore, the luminous efficiency is enhanced greatly from 106 to 223 lm W−1, which is the best result reported now for LD lighting. These results demonstrate that the optimizing YAG:Ce3+ TCPs in a fitting strategy will brighten once again in the next‐generation LD lighting. Based on scanning electron microscopy (SEM) coupled with a cathodoluminescence system, defects and Ce3+ distributions in grains are identified directly for the first time.
Controlling defects by adding nano‐sized MgO and SiO2 enables a high transmittance of nearly 80%. After annealing in air, furthermore, the luminous efficiency is enhanced greatly from 106 to 223 lm W−1. These results demonstrate that the optimization of Y3Al5O12:Ce3+ transparent ceramic phosphors in a fitting strategy will brighten once again the next generation of laser‐driven lighting.
The recently developed FSI-SPH model (Sun et al., 2019c), by combining the multi-resolution δ+-SPH scheme and a Total Lagrangian SPH method, is further extended for more complex three-dimensional ...(3D) Fluid Structure Interaction (FSI) problems. The FSI-SPH model is strengthened with advanced numerical techniques, in which a combination of the Particle Shifting Technique (PST) and the Tensile Instability Control (TIC) is adopted to prevent flow voids induced by the tensile instability. The Adaptive Particle Refinement (APR) is used to refine particles in the boundary layer region and coarsen particles in the far-field to increase local accuracy but reduce overall computational cost. Moreover, the δ+-SPH and Total Lagrangian SPH solvers are coupled through a Modified Sequential Staggered (MSS) algorithm which, on one hand, ensures the numerical accuracy and stability and, on the other hand, improves the efficiency when magnitudes of time steps between the two solvers differ from each other significantly. In the numerical results, challenging 2D and 3D FSI cases are simulated to test the accuracy of the proposed FSI-SPH model. A new FSI benchmark with free-surface is proposed to highlight the advantage of this FSI-SPH model in simulating free-surface viscous flows. In addition, 3D effects in the FSI dam-breaking and sloshing cases are investigated.
•Multi-resolution δ+-SPH model is accurately and efficiently coupled with the Total Lagrangian SPH model.•Complex three-dimensional (3D) Fluid Structure Interaction (FSI) problems are simulated and validated.•A new benchmark named FSI4 is proposed.•The 3D effects in the FSI dam-breaking and sloshing cases are highlighted.
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•Mn2+ markedly enhanced Fe(III)-NTA catalyzed Fenton-like reaction at circumneutral pH.•Ca2+, Mg2+, Co2+ and Cu2+ had no/or little inhibitory effects on such process.•CRMT and DEET ...were rapidly degraded by Fe(III)-NTA_Mn2+ Fenton-like process.•Generation of HO and O2− in Fe(III)-NTA_Mn2+ Fenton-like process were suggested.
In this work, we report a novel Mn2+-mediated Fenton-like process based on Fe(III)-NTA complex that is super-efficient at circumneutral pH range. Kinetics experiments showed that the presence of Mn2+ significantly enhanced the effectiveness of Fe(III)-NTA complex catalyzed Fenton-like reaction. The degradation rate constant of crotamiton (CRMT), a model compound, by the Fe(III)- NTA_Mn2+ Fenton-like process was at least 1.6 orders of magnitude larger than that in the absence of Mn2+. Other metal ions such as Ca2+, Mg2+, Co2+ and Cu2+ had no impacts or little inhibitory effect on the Fe(III)-NTA complex catalyzed Fenton-like reaction. The generation of hydroxyl radical (HO) and superoxide radical anion (O2−) in the Fe(III)-NTA_Mn2+ Fenton-like process were suggested by radicals scavenging experiments. The degradation efficiency of CRMT was inhibited significantly (approximately 92%) by the addition of HO scavenger 2-propanol, while the addition of O2− scavenger chloroform resulted in 68% inhibition. Moreover, the results showed that other chelating agents such as EDTA- and s,s-EDDS-Fe(III) catalyzed Fenton-like reactions were also enhanced significantly by the presence of Mn2+. The mechanism involves an enhanced generation of O2− from the reactions of Mn2+-chelates with H2O2, indirectly promoting the generation of HO by accelerating the reduction rate of Fe(III)-chelates to Fe(II)- chelates.
The considerable performance enhancement of small molecule‐sieving nanofiltration membrane has been achieved by the functional combination between host–guest chemistry and interfacial polymerization ...(IP) for the first time in this work. First, the water‐insolubility of cucurbit6uril (CB6) was ameliorated by constructing host–guest complex (CB6‐PIP) with piperazine. Second, the incorporation of water‐soluble CB6‐PIP in the selective layer via IP leads to the generation of not only the enlarged conventional polyamide network tunnels but also rotaxane tunnels. Such enrichment of solvent transport tunnels contributes to an amazing pure water permeability of 15.5–25.4 Lm−2bar−1h−1, three times higher than that of traditional polyamide membranes, with a high R/MgSO4 of 99.5–92.5%, perfect SO42−/Cl− selectivity due to the electronegative contribution of CB6, as well as untapped potential in organic solvent nanofiltration. This work not only provides a fire‐new strategy to design new type of NF materials but also promotes the application of CBs in many other fields.
Seven transmembrane G protein-coupled receptors (GPCRs) are often phosphorylated at the C terminus and on intracellular loops in response to various extracellular stimuli. Phosphorylation of GPCRs by ...GPCR kinases and certain other kinases can promote the recruitment of arrestin molecules. The arrestins critically regulate GPCR functions not only by mediating receptor desensitization and internalization, but also by redirecting signaling to G protein-independent pathways via interactions with numerous downstream effector molecules. Accumulating evidence over the past decade has given rise to the phospho-barcode hypothesis, which states that ligand-specific phosphorylation patterns of a receptor direct its distinct functional outcomes. Our recent work using unnatural amino acid incorporation and fluorine-19 nuclear magnetic resonance (
F-NMR) spectroscopy led to the flute model, which provides preliminary insight into the receptor phospho-coding mechanism, by which receptor phosphorylation patterns are recognized by an array of phosphate-binding pockets on arrestin and are translated into distinct conformations. These selective conformations are recognized by various effector molecules downstream of arrestin. The phospho-barcoding mechanism enables arrestin to recognize a wide range of phosphorylation patterns of GPCRs, contributing to their diverse functions.
A wireless sensor network (WSN) consists of a group of energy-constrained sensor nodes with the ability of both sensing and communication, which can be deployed in a field of interest (FoI) for ...detecting or monitoring some special events, and then forwarding the aggregated data to the designated data center through sink nodes or gateways. In this case, whether the WSN can keep the FoI under strict surveillance and whether the WSN can gather and forward the desired information are two of the most fundamental problems in wireless sensor networks that need to be solved. Therefore, preserving network connectivity while maximizing coverage by using the limited number of energy constrained nodes is the most critical problem for the deployment of WSNs. In this survey article, we classify and summarize the state-of-the-art algorithms and techniques that address the connectivity-coverage issues in the wireless sensor networks.
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