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Surface treatment is an effective method of enhancing the heat transfer performance of flow boiling. Diamond/Cu, as a particle‐reinforced composite, exhibits heterogeneous surface properties and surface microstructures that play distinct roles in heat transfer. To elucidate the synergistic effect of heterogeneous material surfaces and microstructures, pure copper surface (PC), untreated diamond/Cu surface (DC), and surface‐treated diamond/Cu surface (SDC) are prepared for this experiment. These surfaces demonstrate various combinations of diamond, copper, and their corresponding surface microstructures. DC, characterized by heterogeneous wetting properties, demonstrates a heat transfer coefficient (HTC) that is 9%–24% higher than that of PC. The surface treatment of SDC results in the formation of a superhydrophilic CuO nanosheet structure, significantly enhancing both surface roughness and energy. SDC develops microcracks on the surface of diamond. The increased roughness provides numerous nucleation areas for the hydrophobic diamond, enhancing the overall wettability of the surface when combined with the superhydrophilic CuO region. SDC demonstrates the advantage of enhanced flow boiling on the surface of heterogeneous materials. At the identical heat flux, SDC exhibits a reduction of 5–10 °C in wall superheat and an increase of 38%–47% in HTC. [ABSTRACT FROM AUTHOR]

Common ZnO particles was used to improve the flame retardancy of piperazine pyrophosphate/melamine polyphosphate (PPAP/MPP) in PP composites. 0.5 wt% ZnO exhibited an exceptional synergism by analyzing LOI determination, UL-94 test, and CCT. The LOI increased from 29.9% (no ZnO) to 32.3%. The corresponding flame-retardant rating was improved from UL-94 V-2 to V-0. Additionally, ZnO significantly inhibited the formation of the smoke and CO during the combustion process. The TGA, the component and the structure of the heated FRPP and CCT residues were studied by FTIR, EDS, SEM, Raman spectra and 31P Nuclear Magnetic Resonance, revealing that PPAP/MPP was dominant in the flame retardant process by condensed phase actions. Furthermore, ZnO obviously promoted the formation of the char layer and increased its graphitization degree. Thus, the thermal stability and the strength of the intumescent char layer were improved and then to reinforce the flame retardancy of flame retardant PP (FRPP).

The synergistic fire retardancy of modified melamine resin with pentaerythritol (MF‐PER, a novel green and effective triazine charring agent), and ammonium polyphosphate (APP) in polypropylene was investigated by UL‐94 test, LOI measurement, and cone calorimetry test. It is found that the synergism of MF‐PER is obviously better than pentaerythritol (PER). MF‐PER/APP imparts a fire retardancy mainly by the following mode: in burning process, MF‐PER, and APP are first pyrolyzed respectively into polyols and polyphosphoric acid, which is esterified to form phosphoric ester, and the inert gases make the molten residues foaming; When the temperature increases, and polyphosphoric acid is dehydrated to polymetaphosphoric acid, which dehydrates phosphoric ester to form an intumescent char layer, inducing a fire retardant effect by barrier effect. The graphitization degree of the cone calorimetry test residues of the FR‐PP with MF‐PER is higher than that with PER, which leads to a better synergism. Highlights: Melamine formaldehyde resins modified with pentaerythritol (MF‐PER) as a novel triazine charring agent was designed and synthesized.MF‐PER is synthesized by solid phase method and using hexahydroxymethyl melamine (HMM) instead of cyanuric chloride as raw material, so the emission of three wastes in its synthesis process is very little, only a small amount of formaldehyde and water are produced.MF‐PER has excellent synergistic fire retardancy with APP in polypropylene.The highly efficient and environmentally benign charring agent show great potential for developing more efficient and eco‐friendly IFR. [ABSTRACT FROM AUTHOR]

In order to improve the flame retardant efficiency and smoke‐suppression of piperazine pyrophosphate/melamine cyanurate (PPAP/MCA) in PP, the synergism of ZnO and PPAP/MCA was investigated by limiting oxygen index (LOI) determination, UL‐94 test, and cone calorimetry test (CCT). It is found that ZnO performs an exceptional synergism in flame retardant effect and inhibition on the flame propagation. Besides, ZnO can significantly inhibit the production of the smoke and CO. The TGA of the PP composites, the component and structure analysis of the heated composites and CCT residues reveal that ZnO performs the synergism primarily by the following modes: ZnO promotes obviously the charring of the composite, and improves the thermal stability as well as the strength of the intumescent layer, which brings about an improved flame retardant property and inhibiting ability on the flame propagation. [ABSTRACT FROM AUTHOR]

Summary: The fire‐retardant synergy of bis(1‐methoxy‐2,2,6,6‐tetramethyl‐4‐piperidinyl)sebacate (NORSM) and melamine hydrobromide (MHB)/aluminum diethylphosphinate (ADEP) in polypropylene (PP) has been studied using UL‐94 tests, limiting oxygen index (LOI) determination, and cone calorimetry tests (CCTs). The results indicate that NORSM exhibits exceptional fire‐retardant synergy with ADEP/MHB in PP. For a PP composite with 1.0 wt% of MHB and 1.5 wt% of ADEP, the LOI increased from 19.0% to 26.0%, fire retardation effectivity increased from 0.48 to 2.93, synergy effectivity was as high as 1.99, UL‐94 level was enhanced from none to V‐2, fire performance index increased from 56.4 to 84.8, and various heat release values decreased significantly when the PP composite just discussed combining 0.30 wt% of NORSM. NORSM plays a role in synergy with ADEP/MHB primarily through the following modes: radicals such as CH3O· and aminyl formed by the decomposition of NORSM; PO2·, PO·, and HPO· formed from ADEP; HBr formed from MHB; and quench active radicals such as HO· for combustion and breaking down the radical source, which terminates the chain oxidation reaction for combustion, leading to more exceptional fire retardation in the gaseous phase. [ABSTRACT FROM AUTHOR]

The fire-retardant synergy of tris(1-methoxy-2,2,6,6-tetramethyl-4-piperidinyl)-phosphite (NORPM) and melamine hydrobromide (MHB)/aluminum diethylphosphinate (ADEP) in polypropylene (PP) was characterized by UL-94 tests, limiting oxygen index (LOI) determination and cone calorimetry tests (CCT). NORPM exhibits an exceptional synergy in PP. The LOI and fire-retardant effectivity (EFF) of S-3 (the loadings of MHB and ADEP 1.00 and 1.50 wt%, respectively, no NORPM) were 19.0% and 0.48%, respectively, however, the LOI and EFF of S-15 (the loadings of NORPM, MHB and ADEP 0.2, 1.00 and 1.50 wt%, respectively) significantly increased to 25.5% and 2.85%, respectively, synergistic effectivity (SE) of NORPM is 2.03, and the fire-retardant rating was improved from none to UL 94 V-2 and the total heat release (THR) and peak heat release rate (PHRR) dropped obviously by adding the 0.2 wt% NORPM. The analysis by thermogravimetry-mass spectrum analysis (TG-MS) of the PP samples and the residues in the CCT revealed that NORPM, MHB and ADEP induced the synergy primarily by the following modes: CH3O·, aminyl radicals, CH3·and nitro radicals formed through the cracking of NORPM, along with the free radicals such as PO·, PO2· and HPO· pyrolyzed from ADEP and HBr from MHB, which quenched the active radicals, such as HO·, H·, ROO·, R· and broke down the radical source. The chain oxidation reaction of combustion was accordingly interrupted, which brought about the more exceptional fire-retardant effect than that of MHB/ADEP. [ABSTRACT FROM AUTHOR]

Objective: To observe the clinical effect of repetitive transcranial acupuncture stimulation (rTAS) combined with electroacupuncture (EA) in treatment of acute facial palsy with retroauricular pain., Methods: Sixty-eight patients of acute facial palsy with retroauricular pain were randomly divided into an observation group (34 cases, 3 cases dropped out) and a control group (34 cases, 3 cases dropped out). On the basis of conventional therapy, in the control group, Yangbai (GB 14), Cuanzhu (BL 2), Sibai (ST 2), Quanliao (SI 18), Dicang (ST 4), Yifeng (TE 17), Qianzheng (Extra point) and Taiyang (EX-HN 5) on the affected side, and bilateral Hegu (LI 4) were selected. EA was attached to Yangbai (GB 14) and Cuanzhu (BL 2), and Sibai (ST 2) and Dicang (ST 4), respectively, using intermittent wave. In the observation group, on the basis of the regimen as the control group, rTAS was delivered at Baihui (GV 20) and the 1/5 of the lower motor area on the bilateral sides; EA of dense wave was given at the sites of the mastoidⅠand Ⅱ. The intervention of each group was delivered once a day, 6 times a week as one course for 4 courses and taking a day off every course. Before treatment and at the moment after the first treatment completion, the score of visual analogue scale (VAS) was observed in the two groups and the days of retroauricular pain were recorded. Before and after treatment, the score of Sunnybrook facial grading system (SFGS), the grade of House-Brackmann facial nerve function evaluation system (H-B), the latency and amplitude of the motor conduction from the foramina stylomastoideum to the frontal muscle, the orbicularis oris muscle and the orbicularis oculi muscle on the affected facial nerve, were observed in the patients of two groups and the clinical effect was compared between the two groups after treatment., Results: After treatment, SFGS score was increased ( P <0.05), H-B grade was improved ( P <0.05), the latency was shortened in the motor conduction from the foramina stylomastoideum to the frontal muscle, the orbicularis oris muscle and the orbicularis oculi muscle on the affected facial nerve ( P <0.05) and its amplitude elevated ( P <0.05) when compared with those before treatment in the two groups. In the observation group, SFGS score was higher ( P <0.05), H-B grade was superior ( P <0.05), the latency was shorter in the motor conduction from the foramina stylomastoideum to the frontal muscle, the orbicularis oris muscle and the orbicularis oculi muscle on the affected facial nerve ( P <0.05) and its amplitude was higher ( P <0.05) when compared with those of the control group after treatment. After the completion of the first treatment, VAS score of either group was reduced in comparison with that before treatment ( P <0.05), and the score in the observation group was lower than that of the control group ( P <0.05). The duration of retroauricular pain was shortened in the observation group when compared with that of the control group ( P <0.05). The total effective rate was 87.1% (27/31) in the observation group, which was higher than 77.4% (24/31) of the control group ( P <0.05)., Conclusion: The rTAS combined with EA is effective for reducing neurologic impairment of acute facial palsy and alleviating retroauricular pain in the patients.