Simulation on function mechanism of T1(Al_2CuLi) precipitate in localized corrosion of Al-Cu-Li alloys

1Introduction Al-Li alloys,compared with traditional Al alloys,possess more excellent properties,such as lower density,greater elastic modulus and higher specific strength.In the near future,they would be widely applied in airplane structures.However,they…     

Effect of 2-butyne-1, 4-diol on silver electrodeposition from 5, 5-dimethyl hydantoin solutions

The effect of 2-butyne-1, 4-diol on silver electrodeposition process from 5, 5-dimethyl hydantoin solutions was investigated by means of cyclic voltammetric measurement, scanning electron microscopy (SEM) and X-ray diffraction (XRD).Cyclic voltammetric studies indicate that the reduction process of silver electrodeposition is influenced by adding 2-butyne-1, 4-diol.Owing to its adsorption on the electrode surface, 2-butyne-1, 4-diol moderately hinders the mass transfer of the silver complexed ions from the bulk solution to the outer limit of the electrode double layer and affects the electrocrystallization step.Scanning electron microscopy analysis reveals that the presence of 2-butyne-1, 4-diol in the electrolyte is beneficial and the silver deposits obtained are smoother, more compact and more leveled.X-ray diffraction analysis of the silver deposits obtained at 0.5 g·L-1 2-butyne-1, 4-diol indicated that the (110) plane is the most preferred plane and is not affected by the presence of 2-butyne-1, 4-diol in the electrolyte.     

A novel supercapacitor-fuel cell hybrid cell

A monolithic hybrid fuel cell (MHFC) with a novel configuration was proposed in an effort to improve the fuel cell performance during instantaneous power changes. A modified direct methanol fuel cell (DMFC) with a layer of hydrous ruthenium dioxide (RuO2·xH2O) sandwiched between the anode catalyst layer and membrane was used to demonstrate the principle of the MHFC. Experimental results indicate that the RuO2·xH2O layer is equivalent to a resistor-capacitor transmission line and functions similar to a capacitor in parallel with the anode electrode. The improvement in dynamic response of the MHFC was experimentally confirmed under step current change and square current pulse operating. The ionic conductivity of the RuO2·xH2O layer was also obtained.     

Isolation of Whole-plant Multiple Oscillations via Non-negative Spectral Decompositio

Constrained spectral non-negative matrix factorization（NMF）analysis of perturbed oscillatory process control loop variable data is performed for the isolation of multiple plant-wide oscillatory sources.The technique is described and demonstrated by analyzing data from both simulated and real plant data of a chemical process plant. Results show that the proposed approach can map multiple oscillatory sources onto the most appropriate control loops,and has superior performance in terms of reconstruction accuracy and intuitive understanding compared with spectral independent component analysis（ICA）.     

Mg:Mn:Fe:LiNbO3晶体的全息存储性能

在同成分铌酸锂晶体中掺入0.03?2O3和0.1%MnO2(质量分数),分别掺入0,1%,3%,4.5%,6%的MgO(摩尔分数),用提拉法生长了一系列Mg:Mn:Fe:LiNbO3晶体.检测了Mg:Mn:Fe:LiNbO3晶体的红外光谱和抗光损伤能力.掺0,1%,3%,4.5%Mg的Mg:Mn:Fe:LiNbO3晶体的OH-红外振动峰位于3484cm-1,而掺6%Mg的Mg:Mn:Fe:LiNbO3晶体红外振动峰移到3 535gm-1.采用波长为632nm的He-Ne激光器作为光源,通过二波耦合方法测试晶体的全息存储性能.结果表明:Mg:Mn:Fe:LiNbO3晶体的写入时间和动态范围随掺镁量的增加而显著减小,而光折变灵敏度略有上升,抗光损伤性能增强,其中掺镁量为3%Mg:Mn:Fe:LiNbO3晶体更适合作为全息存储介质.     

3,4-双(4'-氨基呋咱基-3')氧化呋咱的合成及性能

以丙二腈为起始原料,经亚硝化、重氮化、缩合等反应合成出3,4-双(4′-氨基呋咱基-3′)氧化呋咱(DATF),总收率为50%.经测定,DATF的部分理化及爆轰性能为: 密度1.795 g/cm3,熔点170～171 ℃,爆速7 177 m/s(1.530 g/cm3),热分解温度260 ℃,摩擦感度8%(90°摆角),撞击感度60%(10 kg,25 cm),真空安定性(5 g样品,100 ℃,48 h),放气量0.4～0.7 mL.采用差热扫描(DSC)法,测定了DATF的热稳定性及DATF同NC,RDX,HMX和NC/NG体系的相容性.结果表明,DATF具有较好的热稳定性和较低的感度,与RDX,HMX,NC和NC/NG体系有较好的相容性.     

HA/TCP双相陶瓷的生物矿化研究

采用新型动态体外模拟系统对HA/TCP双相陶瓷进行了体外生物矿化性能研究,通过SEM、EDAX、FT-IR等测试手段研究并分析了模拟体液流速以及钙磷离子补充在矿化过程中对样品表面磷灰石晶体生长影响.研究发现,较低的模拟体液流速下样品表面形成针片状碳酸化羟基磷灰石晶体,而在较高的流速下,晶片交错生长,形成网状结构,将样品表面完全覆盖.同时,模拟体液Ca2+的及时补充也有助于矿化层的形成.     

ACH法制取粗MMA工艺浅析

1前言甲基丙烯酸甲基酯(MMA)俗称有机玻璃单体,是一种不饱和酯,在室温下为无色透明液体,易挥发、易燃、易爆,能溶于芳香族的烃类、醚类,微溶于水,与水,甲醇可形成共沸物。在一定条件下可以自身聚合,又易同其他单体形成共聚物。MMA的生产工序包括两部分:首先是原料ACH(丙酮氰醇)和100%H_2SO_4反应合成甲基丙烯酰胺硫酸盐(MAAS),然后该盐发生水解生成甲基丙烯酸(AMA),AMA和原料CH_3OH发生酯化反应生成粗甲基丙烯酸甲酯。反应的方程式如下: