Self-curing triphenol A-based phthalonitrile resin precursor acts as a flexibilizer and curing agent for phthalonitrile resin

Major problems currently limiting the widespread application of phthalonitrile resins are the high precursor melting point and volatility of the curing agent. Herein, a novel self-curing triphenol A-based phthalonitrile resin precursor (TPPA-Ph) was successfully synthesized by reacting α,α,α′-tris(4-hydroxyphenyl)-1-ethyl-4-isopropylbenzene (TPPA) with 4-nitrophthalonitrile (NPh) via nucleophilic substitution. The presence of residual phenolic hydroxyl groups in the TPPA-Ph precursor promoted the curing reaction of phthalonitrile resin in the absence of an additional curing reagent. Self-cured TPPA-Ph resins exhibited relatively low melting points (less than 100 °C), high thermal stability, and a wide processing window (116 °C). Furthermore, the TPPA-Ph precursors contained phenolic hydroxyl and cyano groups that can be used as flexibilizers and curing agents to optimize other phthalonitrile resins. Resorcinol-based phthalonitrile resin (DPPH) cured with various amounts of TPPA-Ph possessed excellent thermal and thermo-oxidative stability with a 5% weight loss temperature exceeding 530 °C, T_gs above 380 °C, and a wide processing window and time. Therefore, as a novel precursor and curing agent for phthalonitrile resins, the triphenol A-based phthalonitrile resin is an ideal resin matrix for high-performance composites with broad application prospects in aerospace, shipping, machinery, and other high-tech fields.

Major problems currently limiting the widespread application of phthalonitrile resins are the high precursor melting point and volatility of the curing agent.     

Lu3+ doping induced photoluminescence enhancement in novel high-efficiency Ba3Eu(BO3)3 red phosphors for near-UV-excited warm-white LEDs

Ba₃Eu(BO₃)₃ (BEB) and Lu³⁺ doped BEB red phosphors were successfully synthesized by a high-temperature solid-state reaction method. X-ray diffraction (XRD) patterns, excitation and emission spectra, decay lifetimes, CIE coordinates, internal quantum efficiency, and thermal stability of these phosphors were systematically studied. Under 395 nm excitation, these phosphors exhibited high-brightness red emissions centred at 611 nm. In addition, it was found that doping appropriate amounts of Lu³⁺ ions into BEB phosphors can improve their photoluminescence intensity and internal quantum efficiency. The integrated emission intensity of BEB:0.3Lu³⁺ phosphor was about 1.34 times that of BEB phosphor. Compared with commercial red phosphor Y₂O₂S:Eu³⁺, BEB:0.3Lu³⁺ phosphor showed better color purity (91.4%) and higher emission intensity (about 3.25 times). Surprisingly, the BEB:0.3Lu³⁺ phosphor had a high internal quantum efficiency of almost 87%, which was higher than that of 83% for BEB phosphors. Meanwhile, the BEB:0.3Lu³⁺ phosphors also exhibited good thermal stability with activation energy around 0.14 eV, and the integrated emission intensity at 423 K remained about 52% of that at 303 K. Finally, by using commercial BaMgAl₁₀O₁₇:Eu²⁺ blue phosphors, commercial (Ba,Sr)₂SiO₄:Eu²⁺ green phosphors, as-prepared BEB:0.3Lu³⁺ red phosphors and a 395 nm near-ultraviolet-emitting light-emitting diode (LED) chip, a prototype warm white LED device was fabricated, which showed good color rendering index (CRI = 84.7) and low correlated color temperature (CCT = 3377 K).

Novel high-efficiency Ba₃Eu(BO₃)₃:Lu³⁺ red phosphors with internal quantum efficiency as great as 87% were developed for near-UV-excited warm-white LEDs.     

依达拉奉干预对Stanford A型急性主动脉夹层围术期肺损伤的效果

目的 研究对Stanford A型主动脉夹层（Stanford type A aortic dissection,AAD)围术期肺损伤的患者,应用依达拉奉对氧合与循环情况、炎性细胞因子水平、机械通气时间、监护室（intensive care unit,ICU）时间、住院时间等的影响。方法 2016年1月1日至2017年1月1日,北京安贞医院心脏外科因Stanford A型主动脉夹层入院手术,围术期符合纳入标准的56例患者,将其随机（简单随机化法,使用RandA1.0软件实现）分为2组,每组28例,分别应用依达拉奉（30mg溶入0.9%氯化钠溶液中,缓慢静脉滴注,返回ICU后即刻给予,2次/24小时,持续至术后72小时）加甲泼尼龙琥珀酸钠强化抗炎方案,与甲泼尼龙琥珀酸钠常规抗炎方案这2种处理 [年龄(岁) 46.7±11.2 vs. 47.3±10.7,p>0.05;男性71.4% vs. 67.9%,p>0.05;术后基础急性生理学和慢性健康状况评分系统Ⅱ(APACHE II) 23.0±4.5 vs. 24.4±4.7,p>0.05]。观察比较二个组别于术后即刻T0、术后6小时T6、术后12小时T12、术后24小时T24、术后48小时T48、术后72小时T72氧合指数、乳酸、心率、血压、炎性细胞因子水平、机械通气时间、ICU时间、住院时间等指标的变化。结果 比较2种措施,发现比较对照组,实验组于T6、T12时的氧合指数有明显提高（174.0±45.2 vs. 150.0±63.1 ,p<0.05;183.2±56.3 vs. 156.0±47.5 ,p<0.05）,于T12、T48、T72时的心率明显改善（96.5±22.3 vs. 115.9±15.8 ,p<0.05;101.5±19.4 vs. 120.3±17.9 ,p<0.05;107.0±17.1 vs.118.3±18.4,p<0.05）,炎性细胞因子中丝氨酸蛋白酶抑制剂E1 （Human Serpin E1）于T72时有所下降[8.2(4.0,16.7) vs. 18.5（14.4,20.1） ,p<0.05],人血管生成素-2（Human Angiopoietin-2）于T24、T72时有所下降[2190.3（1940.8,3326.9） vs. 4353.4（3459.0,9395.1） ,p<0.05;2696.4（2156.7,3784.6） vs. 3929.1（3513.9,4291.4） ,p<0.05],血管内皮生长因子（VEGF）于T6、T24时有所下降[264.5±258.0 vs. 434.4±227.2 ,p<0.05;323.2±231.2 vs. 569.1±406.1 ,p<0.05],晚期糖基化终末产物受体(receptor for advanced glycation end products,RAGE) 于T12、T24、T72时有明显下降（2016.8±1069.4 vs. 2919.9±629.0 ,p<0.05;1915.4±970.9 vs. 2678.1±736.0 ,p<0.05;1709.1±874.1 vs. 2692.1±834.5 ,p<0.05）,住院时间（d）缩短（14.8±6.1 vs. 17.9±5.0 ,p<0.05）。结论 对于Stanford A型主动脉夹层围术期肺损伤的患者,应用依达拉奉强化抗炎可改善患者氧合指数,抑制炎性反应使炎性细胞因子水平明显下降,缩短住院时间,但是对机械通气时间、监护室时间无明显影响。     

Functional metabolomics discover pentose and glucuronate interconversion pathways as promising targets for Yang Huang syndrome treatment with Yinchenhao Tang

Yinchenhao Tang (YCHT), a classic traditional Chinese medicine (TCM) formulae, plays an important role in the treatment of Yang Huang syndrome (YHS). With the emergence of new biomarkers of YHS uncovered via metabonomics, the underlying functional mechanisms are still not clear. Functional metabolomics aims at converting biomarkers derived from metabonomics into disease mechanisms. Here, an integrated non-target metabolomics and IPA strategy were used to investigate the YCHT intervention on YHS. Our metabolomics study has shown that the potential protective effect of YCHT on YHS mice leads to significant changes in the metabolic profile by modulating the biomarkers and regulating the metabolic disorders. Twenty two differential metabolite biomarkers and fifteen involved metabolic pathways were correlated with the regulation of YCHT treatment on YHS. Functional metabolomics identified a core biomarker, d-glucuronic acid in pentose and glucuronate interconversion pathways, which was directly related to the target prediction of UDP-glucuronosyltransferase 1A1 and eventually leaded to a series of disturbances. In conclusion, this study shows that functional metabolomics can discover metabolic pathways as promising targets.

Yinchenhao Tang (YCHT), a classic traditional Chinese medicine (TCM) formulae, plays an important role in the treatment of Yang Huang syndrome (YHS).     

Preparation,characterization, and luminescence properties of double perovskite SrLaMgSbO6:Mn4+ far-red emitting phosphors for indoor plant growth lighting

Mn⁴⁺-activated SrLaMgSbO₆ far-red emitting phosphors with double perovskite structure were prepared by traditional solid-state reaction. The research on the crystal structure of the SrLaMgSbO₆:0.8%Mn⁴⁺ (SLMS:0.8%Mn⁴⁺) phosphors showed that the as-prepared sample was made up of two polyhedrons, [SbO₆] and [MgO₆]. Under the excitation of 333 nm, the SLMS:0.8%Mn⁴⁺ phosphors exhibited an intense far-red emission in the 625–800 nm wavelength range with CIE chromaticity coordinates of (0.733, 0.268), which could match well with the absorption spectrum of phytochrome P_FR. The optimal concentration of Mn⁴⁺ ions in the SLMS:Mn⁴⁺ phosphors was 0.8 mol%. Importantly, the as-prepared SLMS:0.8%Mn⁴⁺ phosphors had an internal quantum efficiency of 35%. The thermal stability of SLMS:0.8%Mn⁴⁺ phosphors was also investigated, and the activation energy was found to be 0.3 eV. Thus, the Mn⁴⁺-activated SLMS phosphors have great potential to serve as far-red emitting phosphors in indoor plant growth lighting.

Novel far-red emitting double perovskite SrLaMgSbO₆:Mn⁴⁺ phosphors were prepared and their photoluminescence properties were studied for applications in indoor plant growth lighting.     

Interface Strength,Damage and Fracture between Ceramic Films and Metallic Substrates

Interface strength, damage and fracture properties between ceramic films and metallic substrates affect the service reliability of related parts. The films’ thickness, grain size and residual stress affect the interface properties and fracture behavior, thus related studies attract great attention. In this paper, the interface damage evolution and fracture behavior between ceramic films and metallic substrates were simulated by developing a three dimensional finite element model of alumina films on Ni substrates with cohesive elements in the interfaces. The interface fracture energy as a key parameter in the simulation was firstly determined based on its thermodynamic definition. The simulation results show the Mises stress distribution and damage evolution of the film/substrate structures during uniaxial tensile loading. Specially, when grain size of the films is in nanoscale, the interface strength increases obviously, agreeing with the previous experimental results. The effects of residual stress on interface properties was further simulated. The interface strength was found to decrease with increasing radial residual force and the axial residual pressure increases the interface strength. When the thickness of the films increases, the interface strength keeps a constant but the speed of interface damage becomes faster, that is, the thicker films show catastrophic fracture. The underlying mechanism of damage speed was analyzed. Understanding these size effects and the effects of residual stress is helpful to guide the design of related parts.