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Hollow polyacrylonitrile (PAN) microspheres can be used as fuel carriers in inertial confinement fusion (ICF) experiments due to their high tensile strength, low permeability to hydrogen isotopes, and resistance to tritium radiation corrosion. Monodisperse oil in water in oil (O1/W/O2) compound droplets were fabricated by the microfluidic technique and then monodisperse hollow polyacrylonitrile microspheres were prepared by the solvent evaporation method. The stability of O1/W/O2 compound droplets was improved by the addition of the surfactant (Dow Corning 749), which reduced the interfacial tension between the O2 phase and the W phase as well as the Laplace pressure on the surface of the compound droplets. The sphericity and the surface quality of the microspheres were also improved by the introduction of DMF droplets into the O2 phase to avoid emulsification, decreasing the DMF mass transfer rate. Therefore, fine monodisperse PAN microspheres with the diameter range of 700–800 µm were successfully prepared. Moreover, the size relationship between the compound droplets and the resulting microspheres was also evaluated, which can be used to predict the sizes of the PAN microspheres. The results provide a method for controllable preparation of monodisperse hollow PAN microspheres for ICF experiments. [Display omitted] • Monodisperse hollow polyacrylonitrile microspheres were successfully prepared by the microfluidic technique. • The effect of the surfactants on the stability of the compound droplets and the quality of resulting microspheres was investigated. • The size relationship between the compound droplets and the microspheres was also studied. [ABSTRACT FROM AUTHOR]

Abstract: Poly(styrene-co-acrylonitrile)/Cloisite 20A (95/5) nanocomposites, having various spatial dispersion levels of the clay, were prepared with controlling clay concentrations in a solvent by the coagulation method. X-ray diffraction, transmission electron microscopy and laser scanning confocal microscopy were used to characterize the structure and morphology of the nanocomposites on a nano-scale and on a micro-scale. Quantitative analysis of clay spatial dispersion in the nanocomposites based on the laser scanning confocal microscopy images was conducted from three different perspectives: 1) clay spatial distribution; 2) the non-clay-occupied domain size; and 3) the relationship between the frequency and intensity of pixels in the images. The results from these quantitative methods indicate that nanocomposites with different spatial dispersion levels of clay in the poly(styrene-co-acrylonitrile) matrix were obtained. Evidently, the ∆d001 data from the X-ray diffraction was found to be not useful in measuring the clay dispersion in the nanocomposites. The effect of clay dispersion on the flammability properties of the nanocomposites and relevant mechanism of the clay dispersion having influence on flammability were also investigated. In radiant gasification experiments at 50 kW/m2, the best clay dispersion yielded a 32% reduction in peak mass loss rate, as compared to the nanocomposites with the worst dispersion. [Copyright &y& Elsevier]

Abstract: A combination of montmorillonite (MT) clay and catalysts was used to explore possible synergistic effects in reducing the flammability of poly(styrene-co-acrylonitrile) (SAN). Several catalysts, including ammonium phosphomolybdate hydrate (NHPMo), melamine phosphomolybdate hydrate (MEPMo), zinc phosphomolybdate hydrate (ZnPMo) and sodium phosphomolybdate hydrate (NaPMo), were used. The combination of MT (Cloisite 20A) with NHPMo showed synergistic enhancement in improving the char formation and reducing the peak mass loss rate of SAN40 as compared with SAN40 composites containing MT or NHPMo alone, while similar synergistic performance was not obtained between MT and NaPMo or ZnPMo or MEPMo. The better flame retardancy with this combination is probably due to the two primary aspects. One is the increased catalytic activity of the combination of Cloisite 20A and NHPMo probably due to the overlapping degradation temperature range of the combination of 20A/NHPMo and SAN40, which probably results in more char formation; the other is more NHPMo being around or on the clay stacks while less is in the galleries of the clay; this probably bridges the clay stacks and strengthens the clay network with char formed during the degradation process. High temperature rheological data confirmed the formation of a stronger network structure in SAN40/20/NHPMo; this benefits flame retardancy by allowing fewer cracks to form in the outer char layer on the polymer mass. The more continuous char layer suppresses bubbles transport of fuel vapors and heat transfer through the char layer, thereby reducing the mass loss rate. [Copyright &y& Elsevier]

Yb3+/Er3+-doped Bi2(MoO4)3−z(WO4)z phosphors were synthesized via a hydrothermal method combined with subsequent calcination. Under the excitation of a light source of 980 nm, Bi2(MoO4)3:Yb3+/Er3+ phosphors exhibited strong upconversion green light and weak red light emissions. By doping WO42− in Bi2(MoO4)3:Yb3+/Er3+ phosphors, the upconversion luminescence intensity of the phosphors significantly enhanced, which is 42 times higher than that of the undoped WO42− phosphor. With an increase in WO42− doping content, the final color coordinates of Bi2(MoO4)3−z(WO4)z:Yb3+/Er3+ phosphors were (0.2352, 0.7274), which is closer to the standard green CIE coordinates. The maximum CP of WO42−-doped phosphors is as high as 116.68%, which is 74.44% higher than that of the undoped WO42− phosphor. Based on the thermally coupled energy levels (TCLs) of Er3+ (2H11/2/4S3/2 → 4I15/2) in Bi2(MoO4)2.7(WO4)0.3:14%Yb3+,3%Er3+ phosphor, the SR value reached a maximum of 0.0081 K−1 at 323 K and the SA value reached a maximum of 0.0099 K−1 at 398 K. The obtained Bi2(MoO4)3−z(WO4)z:Yb3+/Er3+ phosphors are suitable for upconversion luminescent materials for green displays and have potential advantages in optical temperature measurement. [ABSTRACT FROM AUTHOR]

[Display omitted] • LYDD acupuncture alleviates cerebral I/R injury. • LYDD acupuncture suppresses activation of NF-κB pathway in cerebral I/R. • BIRC3, TLR2/4 and TRADD are hub gene of LYDD acupuncture treatment for brain I/R. Ischemic stroke is a permanent neurological impairment resulting from the narrowing or blockage of blood vessels in the brain. The effectiveness of "Lifting Yang to Dredging Du Meridian Manipulation" (LYDD) acupuncture in clinical treatment of ischemic stroke patients has been well-established. Nevertheless, its mechanism is still uncertain. MCAO/R rat models at different time points of reperfusion (24, 36, 48 and 72 h) were constructed, and LYDD acupuncture treatment was performed. Zea-Longa score and TTC staining were used for assessing neurological impairment and cerebral infarct in rats, respectively. The pathological changes of cerebral tissue in each group were observed by HE and Nissl's staining. Cerebral tissue from each group was subjected to RNA-seq, and differentially expressed genes (DEGs) were performed for GO and KEGG enrichment analysis, and hub gene was identified based on the String database and MCODE algorithm. LYDD acupuncture treatment significantly reduced Zea-Longa score, dry-wet weight ratio, infarct area, inflammatory factor levels (IL-1β and TNF-α), cerebral lesions, number of Nissl body and neuronal apoptosis in the MCAO/R model at different time points of reperfusion. A total of 3518 DEGs were identified in the MCAO/R model compared to the control group, and 3461 DEGs were present in the treatment group compared to the MCAO/R model, and they may be implicated in neurotransmitter transmission, synaptic membrane potential, cell junctions, inflammatory response, immune response, cell cycle, and ECM. The expression trends of BIRC3, LTBR, PLCG2, TLR4 and TRADD mRNAs in the Hub gene were consistent with the RNA-seq results, and LYDD acupuncture treatment significantly inhibited MCAO/R-induced p65 nuclear translocation. LYDD acupuncture ameliorates cerebral ischemia-reperfusion injury by inhibiting NF-κB pathway activity. [ABSTRACT FROM AUTHOR]

Ulcerative colitis (UC) is an inflammatory bowel disorder (IBD) characterized by relapsing chronic inflammation of the colon that causes continuous mucosal inflammation. The global incidence of UC is steadily increasing. Immune mechanisms are involved in the pathogenesis of UC, of which complement is shown to play a critical role by inducing local chronic inflammatory responses that promote tissue damage. However, the function of various complement components in the development of UC is complex and even paradoxical. Some components (e.g. C1q, CD46, CD55, CD59, and C6) are shown to safeguard the intestinal barrier and reduce intestinal inflammation, while others (e.g. C3, C5, C5a) can exacerbate intestinal damage and accelerate the development of UC. The complement system was originally thought to function primarily in an extracellular mode; however, recent evidence indicates that it can also act intracellularly as the complosome. The current study provides an overview of current studies on complement and its role in the development of UC. While there are few studies that describe how intracellular complement contributes to UC, we discuss potential future directions based on related publications. We also highlight novel methods that target complement for IBD treatment. [ABSTRACT FROM AUTHOR]

A simple, low-cost and reliable method for coating of solid particles with liquid layer, namely formation of S/W/O compound droplets, is proposed and demonstrated experimentally via a vertical microfluidic T-junction device. At low flow rate ratio of oil (O) to water (W) phase, S/W/O compound droplets containing two solid cores are observed. With the increase of the flow rate of oil phase, S/W/O compound droplets with one solid core inside, also called single encapsulation, can be obtained. In single encapsulation, three typical flow regimes, which are squeezing regime, dripping-like regime, and jetting-like regime, can be quantitatively distinguished by the flow rates of both phases. S/W/O compound droplets, fabricated in the dripping-like regime, show a high monodispersity. Finally, polystyrene coated with polyvinyl alcohol layer (PS-PVA double-layer shells), used as a fuel container in inertial confinement fusion (ICF) experiments, can be successfully prepared via solidification of such compound droplets. [ABSTRACT FROM AUTHOR]

The pollution of phenol wastewater is becoming worse. In this paper, a 2D/2D nanosheet-like ZnTiO3/Bi2WO6 S-Scheme heterojunction was synthesized for the first time through a two-step calcination method and a hydrothermal method. In order to improve the separation efficiency of photogenerated carriers, the S-Scheme heterojunction charge-transfer path was designed and constructed, the photoelectrocatalytic effect of the applied electric field was utilized, and the photoelectric coupling catalytic degradation performance was greatly enhanced. When the applied voltage was +0.5 V, the ZnTiO3/Bi2WO6 molar ratio of 1.5:1 had highest degradation rate under visible light: the degradation rate was 93%, and the kinetic rate was 3.6 times higher than that of pure Bi2WO6. Moreover, the stability of the composite photoelectrocatalyst was excellent: the photoelectrocatalytic degradation rate of the photoelectrocatalyst remained above 90% after five cycles. In addition, through electrochemical analysis, XRD, XPS, TEM, radical trapping experiments, and valence band spectroscopy, we found that the S-scheme heterojunction was constructed between the two semiconductors, which effectively retained the redox ability of the two semiconductors. This provides new insights for the construction of a two-component direct S-scheme heterojunction as well as a feasible new solution for the treatment of phenol wastewater pollution. [ABSTRACT FROM AUTHOR]

Droplets encapsulating solid microparticles with a thin coating layer have extensive applications in the fields of biochemical, advanced materials, and inertial confinement fusion. In this work, the droplet break-up technique is employed to prepare solid–water–oil (S/W/O) conformal droplets with an ultra-thin coating layer. A microfluidic chip, consisting of a T-junction and a Y-junction, was designed and constructed for the controlled preparation of ultra-thin S/W/O conformal droplets by generating–splitting integration. The flow pattern, regime, and dynamic mechanisms of the S/W/O droplet break-up were also experimentally investigated. The results show that there are three break-up regimes: breakup, non-breakup, and transition. Two different modes are observed in the break-up regime: without solid core stagnation and with solid core stagnation. In the case of the solid core without stagnation, the neck goes through three stages: squeezing, transition, and pinch-off. When the solid core stagnates, the neck goes through one more solid core stagnation stage after squeezing. The stagnation percentage decreases as the dispersed phase capillary number increases and increases as the continuous phase capillary number increases. The coating thickness of the S/W/O droplet increases and then decreases as the continuous phase flow rate increases. The coating thickness of the daughter S/W/O droplet was significantly reduced and was less affected by the continuous phase flow rate. [ABSTRACT FROM AUTHOR]

In order to further improve the hydrogenation performance of the existing hydrotreating (HDT) catalysts and explore the structure-activity relationship of the catalysts, a series of Ni modified Y zeolites were successfully synthesized by in-situ synthesis method, and the corresponding NiMo catalysts supported on Ni modified Y zeolites and γ-Al 2 O 3 were prepared for diesel fuel hydrotreating. The effect of Ni modification on the properties of the synthesized xNiY zeolites and the corresponding NiMo/AxNiY catalysts were determined by the characterization techniques such as XRD, ICP-AES, N 2 physical adsorption-desorption, SEM, UV-Vis DRS, Py-FTIR, HRTEM and XPS. The results show the in-situ modification method can achieve a favorable composite effect of Ni species and the Y zeolites and Ni modification can affect the physical-chemical properties of the synthesized Y zeolites and the NiMo/AxNiY catalysts in varying degrees. Although Ni modification led to a slight decrease in the specific surface areas and pore volumes of the Y zeolites, it can promote the particle uniformity and improve the number of acid sites of the Y zeolites, which are beneficial to the adsorption of sulfide molecules. Moreover, the incorporation of Ni into Y zeolites can also effectively improve the number of acid sites of the prepared NiMo/AxNiY catalysts and improve the stacking number of MoS 2 slabs, and enhance the Mo species dispersion, which promote the adsorption and hydrogenation performances of the reactants on the catalysts. Hence, the catalysts containing Ni modified Y zeolites exhibited higher hydrotreating activity compared with the catalyst containing unmodified Y zeolites. Among the four investigated catalysts, the NiMo/A3NiY was found to be the most favorable for the purpose of preparing highly active hydrotreating catalysts for diesel fuels. The incorporation of Ni into Y zeolite improves the utilization rate of active metals on the NiMo/AxNiY catalysts. [Display omitted] • Ni incorporated into Y zeolite was successfully synthesized by in-situ synthesis method. • Ni modification promotes the particle uniformity and improves the number of acid sites of the Y zeolite. • The incorporation of Ni into Y zeolite improves the stacking number of MoS 2 slabs and enhances the Mo species dispersion. • NiMo/A3NiY catalyst showed the best hydrogenation activity. [ABSTRACT FROM AUTHOR]

Background: Facial paralysis is a common clinical disease, it was named intractable facial paralysis when the clinical course more than 2 months. Intractable facial paralysis will produce anxiety and depression, which will seriously affect patients' life and work. Electric acupuncture has been widely used in the treatment of intractable facial paralysis. However, the results of clinical studies on the efficacy and safety have been inconsistent. This study aims to evaluate the efficacy and safety of electric acupuncture for intractable facial paralysis patients by systematic review and meta-analysis, so as to provide clinical decision-making based on evidence-based medicine. Methods: The following databases will be searched by electronic methods: PubMed, Embase, Cochrane Library, Chinese National Knowledge Infrastructure, VIP Database, Wan-fang Data and Chinese Biomedical Database. All of them will be retrieved from the establishment date of the electronic database to March 2022, all included studies will be evaluated risk of bias by the Cochrane Handbook. The total effective rate will be the primary outcome. The systematic review will be conducted with the use of the RevMan5.3 software in this study. Results: This study will obtain efficacy and safety of electric acupuncture for the treatment of intractable facial paralysis. Discussion: This study will provide clinical decision-making based on evidence-based medicine that whether electric acupuncture could be used to treat intractable facial paralysis, and when and how it might be more effective and safety. It will help standardize electric acupuncture treatment strategies for intractable facial paralysis. PROSPERO registration number: CRD42021278541. [ABSTRACT FROM AUTHOR]

The control PAN plastic microspheres were obtained after the evaporation of the middle solvent from silicon oil/PAN in DMF solution/silicon double emulsions (O1/W/O2) which were prepared with stirring method. The pre-oxidation PAN microspheres were prepared after the heating treatment of the PAN plastic microspheres successfully. The structures of the PAN pre-oxidation microspheres were characterized by the Stereomicroscope, the Field Emission Scanning Electron Microscope (FESEM), and the Fourier Transform Infrared spectroscopy (FTIR). It was found that the pre-oxidation PAN microspheres have best mechanical performance than the others at 300 °C. The pre-oxidation microspheres’ pressure-resistance results showed that they can bear greater pressure than the plastic ones, which means that the microspheres’ mechanical strength has been enhanced after the heating treatment. Most pre-oxidation microspheres can bear the pressure higher than 17 MPa, which provide a great prospect in the target application. [ABSTRACT FROM AUTHOR]

Densities, dynamic viscosities, and refractive indices for four binary mixtures formed by dibutyl ether with ethyl caprylate, ethyl caprate, ethyl laurate or ethyl myristate over the whole composition range were measured at T=(293.15–323.15 K) and atmospheric pressure. The excess molar volume (VmE), viscosity deviation (Δη), and refractive index deviation (ΔnD) for the four systems are calculated and then correlated to the Redlich–Kister polynomial. The VmE and Δη values are all negative over the entire range of mole fractions. The absolute values of VmE for the mixtures increase with increasing temperature and the absolute values of Δη decrease with increasing temperature. The ΔnD values with the volume fraction for the four binary systems are all positive over the entire composition range. The experimental results can provide reliable data for the compatibility of biodiesels and their blended fuels. [ABSTRACT FROM AUTHOR]

In this study, a novel approach was presented for controllable preparation of polyacrylonitrile (PAN) hollow microspheres, and PAN-derived graphite carbon microspheres were synthesized through a simple and facile method, overcoming the intrinsic non-graphitizable property of PAN under low temperatures. The pure PAN microspheres and PAN/M (M = Fe, Co, Ni) microspheres were fabricated by the microfluidic technique and solvent evaporation method. Subsequently, the graphitization process was performed for carbon growth of all PAN microspheres at carbonization temperatures of 800 °C, 1000 °C,1200 °C, and 1400 °C, respectively. The effects of transition metals on the stability of compound droplets, monodispersity, and morphology of microspheres were investigated. The carbon resides was given by TG analysis, and the degree of graphite was characterized by the Raman spectra, XRD patterns, and TEM image. The results showed that the three transition metals exhibited different catalytic graphitization effects, leading to a different degree of catalytic graphitization. Understanding the catalytic graphitization effect of Fe, Co, and Ni on PAN microspheres offers new strategies for converting polymer-derived microspheres to invaluable synthetic graphite carbon, which has potential application in upcycling of waste plastics, catalysis, absorption, thermally conductive materials, and energy conversion. [ABSTRACT FROM AUTHOR]