Photo-Optical Instrumentation Engineers (SPIE)

Abstract. A theoretical model for describing the propagation and scattering of energetic species in an extreme ultraviolet (EUV) light lithography source is presented. An EUV light emitting XTREME XTS 13-35 Z-pinch plasma source is modeled with a focus on the effect of chamber pressure and buffer gas mass on energetic ion and neutral debris transport. The interactions of the energetic debris species, which is generated by the EUV light emitting plasma, with the buffer gas and chamber walls are considered as scattering events in the model, and the trajectories of the individual atomic species involved are traced using a Monte Carlo algorithm. This study aims to establish the means by which debris is transported to the intermediate focus with the intent to verify the various mitigation techniques currently employed to increase EUV lithography efficiency. The modeling is compared with an experimental investigation

Clinical assessment of nutrition status score and body mass index in newborns: A comparative study

Background: Fetal growth restriction can occur at any gestational period and is affected by maternal, placental and environmental factors. These factors can cause neonatal mortality or morbidity and long term sequalae. Thereby it is important to assess the nutritional status at birth. Clinical assessment of nutrition status score (CAN) assessment based on birth centile became important. Objectives: Aim was to compare CAN score and BMI birth centiles using pre-designated cut offs for assessing fetal nutrition. Materials and Methods: 1000 newborns cross-Sectional descriptive study. Department of Paediatrics, K.S. Hegde Medical Academy, Mangalore. Nov-2015 to June-2017. Inclusion criteria included term neonates with gestational age >37 completed weeks of gestation by dates or ultra-sonogram.  Neonates with major congenital malformation or syndromes were excluded.  Results: Out of 1000 newborns, 259 newborns (25.9%) had BMI below 10th centile out of which 99(9.9%) had BMI less than 3rd centile suggesting severe malnutrition. Malnutrition as per CAN Score was seen in 319(31.9%) infants. When CAN score and BMI was compared, among the 353 babies who had CAN score less than 25 indicating FM, only 129(36.5%) had BMI less than 10th  centile. In 130 of the 259 infants with BMI less than 10th centile, CAN score was normal

Flowing liquid lithium plasma-facing components – Physics, technology and system analysis of the LiMIT system

The use of low atomic number liquid metals has been shown to have the potential to solve many of the prevalent problems like erosion and radiation losses associated with the interaction of fusion plasma with the plasma facing component (PFC) structures in tokamaks. Since the first evidence of lithium increasing plasma performance in TFTR [1], the benefits of using lithium in fusion environments have been seen in many devices, including CDX-U [2], NSTX [3], LTX [4], and DIII-D [5]. While both fast flow and slow flow concepts have been studied with regards to liquid lithium first wall alternatives, this report will focus on efforts placed on fast flow research and will mainly focus on advancements in the LiMIT device that help to eliminate concerns over the broad use of liquid lithium. Due to the promising TFTR results along with results obtained at the University of Illinois at Urbana-Champaign [6], suitably designed trench structures holding liquid lithium could be an appropriate fast flow candidate for PFC modules in future fusion devices. There are four potential shortcomings of this approach: (1) Droplet ejection, (2) Wetting control, (3) Tritium retention, and (4) Limited heat flux handling. Droplet ejection is discussed in a companion publication [7], while this paper addresses the topics of wetting control and heat flux handling. Limitations in wetting and prevention of lithium creep (i.e. getting and keeping the lithium only where it should be) have been solved by laser-texturing the base material with extreme short laser pulses (pico – femto second) of high power (several 10s of W). Micro- and nano-structuring results indicate that the textured substrates displayed significant change in their wetting properties, increasing the temperature needed to wet from 310 °C to 390 °C. Lastly, initial designs for the Lithium Metal Infused Trenches (LiMIT) [6] showed dryout above 3 MW/m2, but new designs of the trench shaping show potential to be able to handle up to 10MW/m2. Dryout is accompanied by lithium evaporation which is shown to mitigate the incident heat flux, which may be viewed as beneficial [8]. The advances shown here will increase the viability of the LiMIT system in large-scale testing, and allow for extensive design iteration to begin tackling the large powers and heat fluxes present in reactor-relevant systems. Keywords: Liquid lithium, Plasma-facing components, Thermoelectric magnetohydrodynamic