scholarly journals Characterizing Hydration of the Ocean Crust Using Shortwave Infrared Microimaging Spectroscopy of ICDP Oman Drilling Project Cores

Author(s):  
Molly A. Crotteau ◽  
Rebecca N. Greenberger ◽  
Bethany L. Ehlmann ◽  
George R. Rossman ◽  
Michelle Harris ◽  
...  
2019 ◽  
Author(s):  
Arundhati Deshmukh ◽  
Danielle Koppel ◽  
Chern Chuang ◽  
Danielle Cadena ◽  
Jianshu Cao ◽  
...  

Technologies which utilize near-infrared (700 – 1000 nm) and short-wave infrared (1000 – 2000 nm) electromagnetic radiation have applications in deep-tissue imaging, telecommunications and satellite telemetry due to low scattering and decreased background signal in this spectral region. However, there are few molecular species, which absorb efficiently beyond 1000 nm. Transition dipole moment coupling (e.g. J-aggregation) allows for redshifted excitonic states and provides a pathway to highly absorptive electronic states in the infrared. We present aggregates of two cyanine dyes whose absorption peaks redshift dramatically upon aggregation in water from ~ 800 nm to 1000 nm and 1050 nm with sheet-like morphologies and high molar absorptivities (e ~ 10<sup>5 </sup>M<sup>-1</sup>cm<sup>-1</sup>). To describe this phenomenology, we extend Kasha’s model for J- and H-aggregation to describe the excitonic states of <i> 2-dimensional aggregates</i> whose slip is controlled by steric hindrance in the assembled structure. A consequence of the increased dimensionality is the phenomenon of an <i>intermediate </i>“I-aggregate”, one which redshifts yet displays spectral signatures of band-edge dark states akin to an H-aggregate. We distinguish between H-, I- and J-aggregates by showing the relative position of the bright (absorptive) state within the density of states using temperature dependent spectroscopy. Our results can be used to better design chromophores with predictable and tunable aggregation with new photophysical properties.


Author(s):  
M. Hamzah

Classical Oil Country Tubular Goods (OCTG) procurement approach has been practiced in the indus-try with the typical process of setting a quantity level of tubulars ahead of the drilling project, includ-ing contingencies, and delivery to a storage location close to the drilling site. The total cost of owner-ship for a drilling campaign can be reduced in the range of 10-30% related to tubulars across the en-tire supply chain. In recent decades, the strategy of OCTG supply has seen an improvement resulting in significant cost savings by employing the integrated tubular supply chain management. Such method integrates the demand and supply planning of OCTG of several wells in a drilling project and synergize the infor-mation between the pipes manufacturer and drilling operators to optimize the deliveries, minimizing inventory levels and safety stocks. While the capital cost of carrying the inventory of OCTG can be reduced by avoiding the procurement of substantial volume upfront for the entire project, several hidden costs by carrying this inventory can also be minimized. These include storage costs, maintenance costs, and costs associated to stock obsolescence. Digital technologies also simplify the tasks related to the traceability of the tubulars since the release of the pipes from the manufacturing facility to the rig floor. Health, Safety, and Environmental (HSE) risks associated to pipe movements on the rig can be minimized. Pipe-by-pipe traceability provides pipes’ history and their properties on demand. Digitalization of the process has proven to simplify back end administrative tasks. The paper reviews the OCTG supply methods and lays out tangible improvement factors by employ-ing an alternative scheme as discussed in the paper. It also provides an insight on potential cost savings based on the observed and calculated experiences from several operations in the Asia Pacific region.


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