QCD at high temperature and density: selected highlights

I review some of the recent progress in QCD at high temperature and density, with a focus on the nature of the high-temperature transition; cold and dense matter; and hadron properties and transport coefficients at high temperature.

Low-Cost Temperature Transition Mixtures (TTM) Based on Ethylene Glycol/potassium Hydroxide as Reversible CO2 Sorbents

A low-cost Transition Temperature Mixture (TTM) has been synthesized by mixing ethylene glycol and potassium hydroxide as a new non-aqueous CO₂ sorbent. Boric acid has been added to ensure the reversibility of the system and a small amount of water to modulate the viscosity and optimize the performances. The resulting mixtures have been characterized in terms of viscosity, conductivity and density over temperature (therefore ionicity <i>via</i> Walden plots) and the effect of temperature, pressure and the kinetics of the absorption have been evaluated. Under optimized conditions, the four-component mixture EG/KOH/BA/H₂O 3:1:1:3 can absorb 24 g_CO2/kg_sorbent in 30 minutes at 35°C at 1 atm (59 after 4 h) and 60 g_CO2/kg_sorbent in 30 minutes at high pressure (10 and 20 atm, 80 g_CO2/kg_sorbent after 50 min), while the desorption is quantitative after 30 minutes at only 60°C under a gentle N₂ flow. The system is robust enough to ensure multiple absorption/desorption cycles.

Low-Cost Temperature Transition Mixtures (TTM) Based on Ethylene Glycol/potassium Hydroxide as Reversible CO2 Sorbents

A low-cost Transition Temperature Mixture (TTM) has been synthesized by mixing ethylene glycol and potassium hydroxide as a new non-aqueous CO₂ sorbent. Boric acid has been added to ensure the reversibility of the system and a small amount of water to modulate the viscosity and optimize the performances. The resulting mixtures have been characterized in terms of viscosity, conductivity and density over temperature (therefore ionicity <i>via</i> Walden plots) and the effect of temperature, pressure and the kinetics of the absorption have been evaluated. Under optimized conditions, the four-component mixture EG/KOH/BA/H₂O 3:1:1:3 can absorb 24 g_CO2/kg_sorbent in 30 minutes at 35°C at 1 atm (59 after 4 h) and 60 g_CO2/kg_sorbent in 30 minutes at high pressure (10 and 20 atm, 80 g_CO2/kg_sorbent after 50 min), while the desorption is quantitative after 30 minutes at only 60°C under a gentle N₂ flow. The system is robust enough to ensure multiple absorption/desorption cycles.

Structure and properties of polyelectrolyte complexes of various type (chitosan chloride – polyacrilic acid) and triple polyelectrolyte-metalic complexe with cations Cu2+

Using FT-IR-spectroscopy, X-ray diffraction and thermomechanical analysis structure and thermomechanical properties of two nonstoichiometry and one stoichiometry polyelectrolyte complexes (PEC) based on opposite charged polyelectrolytes – strong cationic polyelectrolyte (chitosan chloride) and weak anionic polyelectrolyte (polyacrylic aсid) and triple polyelectrolyte-metal complexes (TPMC) based on stoichometry polyelectrolyte complexes and cations Cu(II) were investigated. It was shown, that chitosan chloride has amorphous-cristallinity structure, which is significantly different from the structure of neat chitosan, and polyacrylic acid posses amorphous structure. Meantime, all PEC samples have amorphous structure, differing from the structure of weak anionic polyelectrolyte, at the same time amorphous structure of nonstoichiometric PECs insignificantly different from that of stoichiometric polyelectrolyte complexes. Additionally, amorphous structure of TPMC has another structure, compared to all PEC. According to thermomechanical analysis, all PECs have one temperature transition from glassy to highly elastic state (from 77 to 84 °C). The deformation value of the samples of nonstoichiometric PEC is similar and somewhat less than the deformation of the stoichiometric PEC. The TPMC sample has two glass transitions (81 and 226 °C), and his high-temperature transition characterizes the segmental mobility of fragments of macromolecules of one stoichiometric PEC, the polar groups of which form chelate circles with Cu (II) cations. Deformation parameter of the TPMC is higher in comparison with the stoichiometric polyelectrolyte complexes. Keywords: structure, properties, deformation, ionic force, cationic Cu(II), polyelectrolyte, polyelectrolyte-metal complexes, chitosan chloride, polyacrylic acid, X-ray diffraction, thermomechanical analysis.

The Role of Manipulating Photoperiod and Temperature in Oocyte Development of the Polychaete Hediste diversicolor (O.F. Müller, 1976)

Three different experiments were conducted to examine the oocyte development of the polychaete Hediste diversicolor in response to changing photoperiod and temperature at three different periods of oogenesis. In experiment I, worms collected during summer were reared under constant or decreasing photoperiod and temperatures to test the combined effects of the summer–autumn photoperiod and temperature transition on oogenesis. The result showed females collected during summer showed the highest oocyte growth when exposed to constant temperatures combined with decreasing photoperiod and decreasing temperature combined with constant photoperiod. In experiment II, worms collected in late autumn were under mimicked or shortened seasonal changes in photoperiod to evaluate the effect of accelerated change on oocyte growth. The result showed worms had 1.5 times faster oocyte growth rates when exposed to accelerated rate of change in photoperiod (2.5 times faster). In experiment III, worms collected in spring were exposed to different temperature regimes to examine the effect of raising temperature on the synchronization of oocyte growth and maturation. The results showed worms collected in spring showed increased temperatures will increase oocyte maturation synchronicity. It was concluded temperature and photoperiod transition can increase the oocyte development.