scholarly journals HRTEM and EELS Studies on the Structural and Chemical Modification of MoS2 and Graphite During In-situ Reactions with Li and Na

2020 ◽  
Vol 26 (S2) ◽  
pp. 2410-2412
Author(s):  
Chanchal Ghosh ◽  
Manish Singh ◽  
Matthew Janish ◽  
Shayani Parida ◽  
Avinash M Dongare ◽  
...  
2021 ◽  
Vol 203 ◽  
pp. 109538
Author(s):  
Boan Xu ◽  
Ping Jiang ◽  
Shaoning Geng ◽  
Yilin Wang ◽  
Jintian Zhao ◽  
...  

2021 ◽  
Vol 14 (1) ◽  
pp. 363-387
Author(s):  
Bo Cheng ◽  
Qi Tang ◽  
Che Zhang ◽  
Xing Chen

As one of the major types of biomacromolecules in the cell, glycans play essential functional roles in various biological processes. Compared with proteins and nucleic acids, the analysis of glycans in situ has been more challenging. Herein we review recent advances in the development of methods and strategies for labeling, imaging, and profiling of glycans in cells and in vivo. Cellular glycans can be labeled by affinity-based probes, including lectin and antibody conjugates, direct chemical modification, metabolic glycan labeling, and chemoenzymatic labeling. These methods have been applied to label glycans with fluorophores, which enables the visualization and tracking of glycans in cells, tissues, and living organisms. Alternatively, labeling glycans with affinity tags has enabled the enrichment of glycoproteins for glycoproteomic profiling. Built on the glycan labeling methods, strategies enabling cell-selective and tissue-specific glycan labeling and protein-specific glycan imaging have been developed. With these methods and strategies, researchers are now better poised than ever to dissect the biological function of glycans in physiological or pathological contexts.


Metals ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 554
Author(s):  
Fehmi Nair ◽  
Mustafa Hamamcı

The objective of this study is to investigate the impact behavior of iron-based composites reinforced with boron carbide (B4C) particles and in-situ synthesized iron borides (Fe2B/FeB). The composite specimens (Fe/B4C) were fabricated by hot-pressing under a pressure of 250 MPa at 500 °C, and sintered at a temperature of 1000 °C. The effects of the reinforcement ratio on the formation of in-situ borides and impact behavior were investigated by means of different volume fractions of B4C inside the iron matrix: 0% (un-reinforced), 5%, 10%, 20%, and 30%. Drop-weight impact tests were performed by an instrumented Charpy impactor on reinforced and un-reinforced test specimens. The results of the impact tests were supported with microstructural and fractographical analysis. As a result of in-situ reactions between the Fe matrix and B4C particles, Fe2B phases were formed in the iron matrix. The iron borides, formed in the iron matrix during sintering, heavily affected the hardness and the morphology of the fractured surface. Due to the high amount of B4C (over 10%), porosity played a major role in decreasing the contact forces and fracture energy. The results showed that the in-situ synthesized iron boride phases affect the impact properties of the Fe/B4C composites.


Author(s):  
Mohammad Shahid Raza ◽  
Susmita Datta ◽  
Partha Saha

Closed-cell aluminium foam, a porous structure, is effectively used for insulation, structural applications, packaging and filtering. Cutting of aluminium foam with the help of fibre laser is an efficient method due to the inherent advantages of fibre laser. Laser cutting of aluminium foam was carried out using a 2-kW fibre laser system for varying process parameters and different assist gas environments. Use of different foaming agents results in the generation of gas-filled pores. During the laser cutting process, the interaction of these gas-filled pores with assist gas results in in-situ reactions, generating different kerf quality. This interaction effect of foam cutting was reported using optical, metallurgical and thermal analysis. Thermal cycles were recorded to understand the occurrence of different in-situ reactions. From the temperature signal for different assist gases, oxygen showed the highest temperature, followed by nitrogen and argon. Argon assist gas gave minimum kerf width, while nitrogen assist gas produced minimum dross. Elemental and phase analysis showed the presence of new compounds and intermetallics in the cut section that stipulated the occurrence of in-situ reactions during the cutting process. The internal pore surface showed the presence of spatter in case of oxygen, while nitrogen and argon gas environment showed relatively less pore-clogging.


2008 ◽  
Vol 403 ◽  
pp. 251-252
Author(s):  
A. Kalemtas ◽  
Gürsoy Arslan ◽  
Ferhat Kara

In the present study highly dense (open porosity < 1 %), light-weight (d £ 2.85 g/cm3) and Al4C3-free non-oxide ceramic-metal composites were produced at comparatively low temperatures ( 1250°C) by pressurless melt infiltration. Phase analysis of the SiC-B4C-Al composites revealed that a significant amount of hygroscopic Al4SiC4 and Al4C3 phases were formed. Si3N4 powder was added in different amounts to the SiC-B4C powder batches to suppress formation of these phases via in-situ reactions during the infiltration process. X-ray diffraction results of the SiC-B4C-Si3N4-Al composites confirmed that the incorporation of Si3N4 to the SiC-B4C system reduced or eliminated the formation of the hygroscopic phases and resulted in in-situ formation of AlN, SiC and Si phases in the composite.


Author(s):  
Derek H. R. Barton ◽  
William B. Motherwell ◽  
Ethan S. Simon ◽  
Samir Z. Zard

Sign in / Sign up

Export Citation Format

Share Document