One-Step Synthesis and Size Control of Dendrimer-Protected Gold Nanoparticles: A Heat-Treatment-Based Strategy

2003 ◽  
Vol 24 (17) ◽  
pp. 1024-1028 ◽  
Author(s):  
Xuping Sun ◽  
Xiue Jiang ◽  
Shaojun Dong ◽  
Erkang Wang
2015 ◽  
Vol 1102 ◽  
pp. 3-6
Author(s):  
In Won Kim ◽  
Sun Ig Hong

Creep properties of one-step and two-step annealed Zr-1Nb-0.12O cladding tubes were studied. Creep tests were carried out at 450~500 °C with the applied stress between 80MPa and 120MPa The creep rates of the two-step annealed Zr-1Nb-0.12O alloy were found to be slower than those of the one-step annealed Zr-1Nb-0.12O alloy. The creep rate decreased with increase of grain size with annealing for Zr-1Nb-0.12O at intermediate temperatures, suggesting the creep resistance can be enhanced by the grain size control. The creep life of two-step annealed Zr-1Nb-0.12O increased over the one-step annealed Zr-1Nb-0.12O by the factor of 18~20 despite the greater initial instantaneous strain.


2012 ◽  
Vol 8 (3) ◽  
pp. 335-342 ◽  
Author(s):  
Xuping Sun ◽  
Xiaoyun Qin ◽  
Jianming Hu ◽  
Yonglan Luo ◽  
Wenbo Lu ◽  
...  

Metals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 492
Author(s):  
Jan Foder ◽  
Jaka Burja ◽  
Grega Klančnik

Titanium additions are often used for boron factor and primary austenite grain size control in boron high- and ultra-high-strength alloys. Due to the risk of formation of coarse TiN during solidification the addition of titanium is limited in respect to nitrogen. The risk of coarse nitrides working as non-metallic inclusions formed in the last solidification front can degrade fatigue properties and weldability of the final product. In the presented study three microalloying systems with minor additions were tested, two without any titanium addition, to evaluate grain size evolution and mechanical properties with pre-defined as-cast, hot forging, hot rolling, and off-line heat-treatment strategy to meet demands for S1100QL steel. Microstructure evolution from hot-forged to final martensitic microstructure was observed, continuous cooling transformation diagrams of non-deformed austenite were constructed for off-line heat treatment, and the mechanical properties of Nb and V–Nb were compared to Ti–Nb microalloying system with a limited titanium addition. Using the parameters in the laboratory environment all three micro-alloying systems can provide needed mechanical properties, especially the Ti–Nb system can be successfully replaced with V–Nb having the highest response in tensile properties and still obtaining satisfying toughness of 27 J at –40 °C using Charpy V-notch samples.


Author(s):  
G. Yu. Shakhgil’dyan ◽  
A. A. Mikhailov ◽  
T. O. Lipat’eva ◽  
K. I. Piyanzina ◽  
E. A. Kolesnikov ◽  
...  

2013 ◽  
Vol 2013 ◽  
pp. 1-4 ◽  
Author(s):  
M. Rafiq H. Siddiqui

Dodecyl sulfide, dodecyl amine, and hexylamine were shown to act as surrogate ligands (L) via metastable gold nanoparticles. By collating analytical and spectroscopic data obtained simultaneously, empirical formula Au24L was assigned. These impurity-free nanoparticles obtained in near quantitative yields showing exceptional gold assays (up to 98%Au) were prepared by a modification of the two-phase method. Replacement reactions on the Au24L showed that Au:L ratios may be increased (up to Au55:L (L= (H25C12)2S)) or decreased (Au12:L (L= H2NC12H25and H2NC6H13)) as desired. This work encompassing the role of analytical techniques used, that is, elemental analysis, variable temperature1H NMR, FAB mass spectrometry, UV-Vis spectroscopy, thin film X-ray diffraction, and high-resolution electron microscopy (HREM) has implications in the study of size control, purity, stability, and metal assays of gold nanoparticles.


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