Papers by Keyword: Raman Spectrometry

Abstract: In recent years, solid clathrate gas hydrates are considered to be promising materials for hydrogen storage because they can trap molecular hydrogen within their cages formed by a hydrogen-bond water network. In this paper, we firstly synthesized the nitrogen hydrates, and then used these hydrates for hydrogen storage. The H₂ storage potential in these hydrates is investigated by Raman spectrometry technique. The spectral properties show that the multiple H₂ occupancies of large cages of N₂ hydrates have been realized under mild condition (16 MPa and 255 K) when exposing N₂ hydrates in pressurized H2 gas. The results suggest that nitrogen clathrate hydrates are prospective media for H₂ storage and may help to design and produce new hydrogen storage materials.

Abstract: Dry water (DW) is a powder-like, solidified form of water, where water droplets are surrounded by silica nanoparticles. DW is considered to be an effective medium for gas storage because it can slurp up gases which combine the water molecules to form clathrate hydrate. In this paper, DW was prepared by mixing water and hydrophobic silica particles (H18) at high speeds, and based on which, dry water methane hydrates (DW-MH) were synthesized under certain conditions. The characteristics of DW and DW-MH were investigated by Raman spectroscopy. The results show that DW-MH is a typetical sI clathrate hydrate with hydration number around 5.9. The storage capacity in clathrate hydrate prepared with methane and four different materials, i.e. DW, powder ice, Sodium Dodecyl Sulfate (SDS) solution and liquid water, was measured by volumetric method. The results showed that DW is prospective medium for gas storage that can increase much higher of the storage capacity compared to other materials.

Abstract: The focus of this research article is on the requirement, preparation and application of an improved material system composed of boron and carbon. These are known as boron rich boron carbides. The ability to form BRBC other than widely studied B4C composition through solid state reactive processes; hold an appeal owing to their potential for a variety of application in tribological, refractory, ballistic, nuclear energy, aerospace and other manufacturing industries. Study of the boron-carbon phase diagram, combined with the available literatures on ‘low yield’ vapor deposition processes and boron doping of B4C to prepare BRBC provided the impetus for this investigation on BRBC through solid state reactive processes, mainly micropyretic and plasma. This article summaries the ‘high yield’ experimental studies carried out for obtaining BRBC and their encouraging performance with respect to existing B4C composition based products.