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101.
H.M. Zhu G. ShaJ.W. Liu C.L. Wu C.P. LuoZ.W. Liu R.K. ZhengS.P. Ringer 《Journal of Alloys and Compounds》2011,509(8):3526-3531
The microstructures and mechanical properties of the new quaternary Mg-6Zn-xCu-0.6Zr alloys (x = 0, 0.5, 1.0 and 2.0 wt.%) have been investigated. The results show that the Cu content has a significant effect on the age-hardening response, tensile performance and fracture behavior of the alloys. The addition of 0.5 wt.% Cu resulted in a remarkable age-hardening response and a striking improvement of the room temperature tensile properties after an isothermal ageing at 180 °C. However, an excessive Cu addition of 2.0 wt.% caused the formation of continuous brittle grain-boundary intermetallic particles, thus degrading the age-hardening response and the mechanical properties of the alloy. The microstructural factors associated with the improvements in the mechanical properties are discussed in detail. 相似文献
102.
103.
榆树井选煤厂煤泥水系统工艺设计探讨 总被引:2,自引:0,他引:2
针对榆树井选煤厂入洗原煤中矸石易泥化的特点,阐述了煤泥水系统工艺设计过程中设备的选择、浓缩机和压滤机的选型、浓缩车间和压滤车间工艺布置、自动加药系统设置等情况,针对生产中暴露出的问题,提出了改进措施;煤泥水系统的正常运行,保证了选煤工艺清洁生产。 相似文献
104.
介绍了湿型砂各组分的作用,论述了型砂性能与其组分的关系,认为控制好有效膨润土量和有效添加剂量是控制型砂质量的关键,结合生产实例说明了型砂质量的控制要点;指出提高型砂质量控制水平、生产优质铸件和实现铸造生产循环用砂是铸造生产节能减排的根本方法之一。 相似文献
105.
Photo‐Induced Functionalization of Spherical and Planar Surfaces via Caged Thioaldehyde End‐Functional Polymers 下载免费PDF全文
Michael Kaupp Alexander S. Quick Cesar Rodriguez‐Emmenegger Alexander Welle Vanessa Trouillet Ognen Pop‐Georgievski Martin Wegener Christopher Barner‐Kowollik 《Advanced functional materials》2014,24(36):5649-5661
The synthesis and application of a novel reversible addition‐fragmentation chain transfer (RAFT) agent carrying a photocaged thioaldehyde moiety is described (λmax = 355 nm). RAFT polymerization of styrene, dimethylacrylamide and a glycomonomer is evidenced (3600 g mol?1 ≤ Mn ≤ 15 000 g mol?1; 1.07 ≤ ? ≤ 1.20) with excellent end‐group fidelity. The photogenerated thioaldehyde on the chain ends can undergo hetero Diels–Alder reactions with dienes as well as reactions with nucleophiles. The terminal photoreactive polymers are photografted to porous diene‐reactive polymeric microspheres. The grafted particles are in‐depth characterized via scanning electron microscopy, elemental analysis, X‐ray photoelectron spectroscopy, and high resolution FT‐IR microscopy, leading to a qualitative as well as quantitative image of the core–shell objects. Grafting densities up to 0.10 molecules nm?2 are reached. The versatility of the thioaldehyde ligation is evidenced by spatially resolved grafting of polystyrene onto nucleophilic groups present in poly (dopamine) (PDA)‐coated glass slides and silicon wafers via two‐photon direct laser writing (DLW) imaged by ToF‐SIMS. The combination of thioaldehyde ligation, RAFT polymerization, and DLW allows for the spatially resolved grafting of a vast range of polymers onto various substrates in any desired pattern with sub‐micrometer resolution. 相似文献
106.
In the last decade, interest in the functionalization of surfaces and materials has increased dramatically. In this regard, click chemistry deserves a central focus because of its mild reaction conditions, high efficiency, and easy post‐treatment. Among such novel click reactions, those that do not require any metal catalyst are of special interest, as metals may have undesirable effects in many fields. In this Review, the backgrounds and application of such metal‐free click reactions for the modification of surfaces are highlighted. 相似文献
107.
通过光学显微镜,配备能量色散光谱仪的扫描电子显微镜,X射线衍射仪,浸泡法和电化学测试的方法研究了Mn的添加对挤压Mg-Zn-Y-Nd合金在3.5wt.%NaCl溶液中的微观组织和腐蚀行为的影响。结果表明,在研究的Mg-Zn-Y-Nd合金中添加Mn可以诱导Mg3Y2Zn3(I相)沉淀,可以抑制热挤压过程中动态再结晶(DRX)晶粒的粗化。同时,添加了Mn也可以提高合金的耐腐蚀性。不含Mn的Mg-5.6Zn-1Y-0.4Nd合金与含锰1.0 wt.%的Mg-5.6Zn-1Y-0.4Nd合金腐蚀速率分别为18.78 mm·y-1和9.89mm·y-1。而耐腐蚀性的提高主要归因于腐蚀产物层保护性的增强。 相似文献
108.
109.
Tetsuya Yamamoto Azamat Zhumagazin Takuma Furusawa Ryoji Tanaka Tetsu Yamakawa Yohei Oe Tetsuo Ohta 《Advanced Synthesis \u0026amp; Catalysis》2014,356(17):3525-3529
Cyclometallated NHC palladium complexes prepared from palladium(II) acetate [Pd(OAc)2] and unsymmetrical 1,3‐diarylimidazolinium salts catalyzed the hydroxymethylation of (hetero)arylboronic acids using an excess amount of formalin to afford (hetero)arylmethanols in good to satisfactory yields.
110.
Jianlin Zhang Yulong Zhang Xiaohua Liu Jing Guo Weidi Cao Lili Lin Xiaoming Feng 《Advanced Synthesis \u0026amp; Catalysis》2014,356(17):3545-3550
An enantioselective protonation by means of chiral scandium complex‐catalyzed aza‐Michael reaction was realized. A series of α‐aryl‐substituted vinyl ketones reacted with pyrazoles smoothly, affording the corresponding enantiomerically enriched pyrazole derivatives with excellent results (up to 99% yield, 94% ee). Water and hydrogen chloride were found to accelerate the protonation process.