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991.
A new multifunctional ionic liquid-based metal–organic hybrid (PMAIL) was synthesized by anion exchange between as-synthesized phosphonate-based ionic liquid and phosphomolybdic acid and applied to epoxy resin (EP) as an efficient flame retardant. As expected, with only 1 wt% addition of PMAIL, the char yield of EP-PMAIL1 composite at 700 °C was significantly improved by 108.3% from 12.0% for neat epoxy resin to 25.0%, demonstrating the outstanding catalytic charring effect of PMAIL. Meanwhile, EP-PMAIL6 composite (6 wt% addition) can reach V-0 rating in the UL-94 vertical burning tests easily, and its peak heat release rate and total smoke production of EP-PMAIL6 were dropped by 31.0 and 15.4%, respectively, compared with neat EP. Moreover, the results from cone calorimetry tests showed that the char yield of EP-PMAIL6 was enhanced by 162% from 9.5 to 24.9% compared with neat EP, resulting in a strong intumescent char layer structure with outstanding fire retardance and mechanical properties. The thermo-oxidative stable protective layer retarded the transfer of heat and flammable volatiles during combustion and protected the epoxy matrix from further degradation. In conclusion, our results might provide a new perspective for producing composites with excellent flame retardancy and smoke suppression properties using ionic liquid-based metal–organic hybrid.  相似文献   
992.
993.
Lv  LinTao  Yuan  QinQin  Li  ZhiXun 《Multimedia Tools and Applications》2019,78(16):22643-22666
Multimedia Tools and Applications - This paper proposes a new algorithm for iris feature extraction. The algorithm uses the odd symmetric 2D Log-Gabor filter to analyze the phase and amplitude of...  相似文献   
994.
Electricity and water from renewable hydropower plant are used as input for electrolysis unit to generate hydrogen, while CO2 is captured from 600 MW supercritical coal power plant using post-combustion chemical solvent based technology. The captured CO2 and H2 generated through electrolysis are used to synthesize methanol through catalytic thermo-chemical reaction. The methanol synthesis plant is designed, modeled and simulated using commercial software Aspen Plus®. The reactor is analyzed for two widely adopted kinetic models known as Graaf model and Vanden-Bossche (VB) model to predict the methanol yield and CO2 conversion. The results show that the methanol reactor based on Graaf kinetic model produced 0.66 tonne of methanol per tonne of CO2 utilized which is higher than that of the VB kinetic model where 0.6 tonne of methanol is produced per tonne of CO2 utilized. The economic analysis reveals that 1.2 billion USD annually is required at the present cost of both H2 production and CO2 abatement to utilize continuous emission of 3.2 million tonne of CO2 annually from 600 MW supercritical coal power unit to synthesize methanol. However, sensitivity analysis indicates that methanol production becomes feasible by adopting anyone of the route such as by increasing methanol production rate, by reducing levelised cost of hydrogen production, by reducing CO2 mitigation cost or by increasing the current market selling price of methanol and oxygen.  相似文献   
995.
996.
本文对利用雾化法直接制备出Y、Ti过饱和固溶的粉体合金,经短时机械合金化和热等静压成型制备纳米结构9Cr-ODS钢技术进行了研究.采用扫描电镜和X射线衍射研究雾化合金粉与短时球磨后雾化合金粉的形貌特征与组织的演化.通过高分辨透射电镜和电子背散射衍射研究热固化成型后ODS钢的微观组织.测试了雾化粉和球磨8 h合金粉热固化成型样品的应力-应变曲线.结果表明,用短时球磨雾化粉制备的ODS钢晶粒尺寸更加细小、形成高密度纳米尺寸的析出相.与常规方法制备的ODS钢相比,抗拉强度略高、塑性显著提高、球磨时间大幅缩短.  相似文献   
997.
GW501516-activated peroxisome proliferator-activated receptor (PPAR) β/δ and G-protein-coupled receptor (GPR) 40 were shown to protect pancreatic β cells against lipoapoptosis. Therefore, this study aimed to investigate whether activated PPARβ/δ could protect type 2 diabetic rats from lipoapoptosis through regulation of GPR40 and to compare the protective effects of activated PPARβ/δ and PPARγ. We made an animal model of type 2 diabetic lipoapoptosis by feeding spontaneously type 2 diabetic Goto–Kakizaki (GK) rats with a high-fat diet (HFD) to evaluate the effects of PPARβ/δ on islet β cell apoptosis. And, treated INS-1 cells with 0.5 mM palmitate (PAM) in the absence/presence of GW501516 (a specific agonist of PPAR β/δ) and with/without transfection of GPR40 siRNA to explore the underlying molecular mechanism. HFD aggravated GK rats' poorer INSR30, lower mass, greater apoptosis of β cells, lower mass, and lower expression of GPR40, which were similarly improved by GW501516 at 3 or 6 mg/kg day and pioglitazone. Compared with pioglitazone, GW501516 caused more weight loss and had no effect on insulin resistance. GW501516 protected INS-1 cells from PAM-induced apoptosis by upregulating GPR40 and activating Akt/Bcl-2/caspase-3. Activated extracellular regulated protein kinases (ERK) was relevant to the lipoapoptosis in INS-1 cells, but was not involved in the antilipoapoptotic effect of GW501516. These results showed that the PPARβ/δ agonist GW501516 protected β cells from lipoapoptosis and improved β cell mass by upregulating GPR40 and activating the Akt/Bcl-2/caspase-3 pathway, but not the ERK-signaling pathway.  相似文献   
998.
The subsolidus phase relation of the system ZnO–Li2O–MoO3 has been investigated by X-ray diffraction (XRD) analyses. The phase diagram has been constructed. There are six binary compounds and one ternary compound in this system. The phase diagram comprises nine three-phase regions. The ternary compound Li2Zn2(MoO4)3 is refined by the Rietveld method. It belongs to an orthorhombic system with space group Pnma and lattice constants a = 5.1114 Å, b = 10.4906 Å, c = 17.6172 Å.  相似文献   
999.
A valence change from Eu3+ to Eu2+ was observed in the europium ion-doped ZnO–B2O3–P2O5 glasses prepared at high temperature in air. The fluorescence emission spectrum of the sample consists of a broad emission band ascribed to the 5d–4f transition of Eu2+ ion and sharp emission peaks assigned to the transitions of 5Do7FJ (J = 0, 1, 2, 3, and 4) of Eu3+ ion, indicating that part of Eu3+ can be reduced into Eu2+ in the glass. A charge compensation model is proposed. The rigid tetrahedral network structure of glasses plays an important role in stability of Eu2+. The fabrication conditions are also studied.  相似文献   
1000.
铝合金结构腐蚀损伤性能评价指标   总被引:1,自引:0,他引:1  
以试验为基础,结合有限元方法对遭受腐蚀损伤的铝合金结构性能进行了研究。将铝合金试验件在不同的腐蚀条件下进行预腐蚀,对预腐蚀后的试件进行疲劳加载试验。利用光学显微镜和扫描电镜对腐蚀损伤形貌进行观测和分析,对描述铝合金腐蚀损伤性能的两个关键参数:腐蚀损伤度、腐蚀损伤平均深度进行了实验观测和有限元分析。结果表明这两个参数可以作为铝合金结构腐蚀损伤性能的评价指标。  相似文献   
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