Integrating Visual and Energy Criteria for Optimal Window Design in Temperate Climates

Building codes and certifications require maximal building performance in different aspects. However, focusing on achieving a single purpose can prevent obtaining additional ones. This work aims to help building designers balance energy and visual performance design criteria. The difficulty to achieve many goals resides in high degrees of complexity when many building features must be considered in an infinite number of possible design solutions. Multi-objective optimization techniques start to be applied in building science, but different appropiate assessment criteria applied to a single problem can lead to diverse valid solutions. A brief review was made of commonly used energy consumption and visual comfort and performance criteria. The study was made through whole-building computer simulations of a standardized test room. This provided a solution space with "compromise sizes" satisfying both energy and visual aspect objectives. However, unprotected windows cannot meet all these criteria. This makes the provision of sun-protecting elements necessary. A selection procedure based on design needs is detailed

Optical symmetries and anisotropic transport in high-Tc superconductors

A simple symmetry analysis of in-plane and out-of-plane transport in a family of high temperature superconductors is presented. It is shown that generalized scaling relations exist between the low frequency electronic Raman response and the low frequency in-plane and out-of-plane conductivities in both the normal and superconducting states of the cuprates. Specifically, for both the normal and superconducting state, the temperature dependence of the low frequency $B_{1g}$ Raman slope scales with the $c-$axis conductivity, while the $B_{2g}$ Raman slope scales with the in-plane conductivity. Comparison with experiments in the normal state of Bi-2212 and Y-123 imply that the nodal transport is largely doping independent and metallic, while transport near the BZ axes is governed by a quantum critical point near doping $p\sim 0.22$ holes per CuO$_{2}$ plaquette. Important differences for La-214 are discussed. It is also shown that the $c-$ axis conductivity rise for $T\ll T_{c}$ is a consequence of partial conservation of in-plane momentum for out-of-plane transport.Comment: 16 pages, 8 Figures (3 pages added, new discussion on pseudogap and charge ordering in La214

Whole-genome sequencing reveals host factors underlying critical COVID-19

Critical COVID-19 is caused by immune-mediated inflammatory lung injury. Host genetic variation influences the development of illness requiring critical care1 or hospitalization2,3,4 after infection with SARS-CoV-2. The GenOMICC (Genetics of Mortality in Critical Care) study enables the comparison of genomes from individuals who are critically ill with those of population controls to find underlying disease mechanisms. Here we use whole-genome sequencing in 7,491 critically ill individuals compared with 48,400 controls to discover and replicate 23 independent variants that significantly predispose to critical COVID-19. We identify 16 new independent associations, including variants within genes that are involved in interferon signalling (IL10RB and PLSCR1), leucocyte differentiation (BCL11A) and blood-type antigen secretor status (FUT2). Using transcriptome-wide association and colocalization to infer the effect of gene expression on disease severity, we find evidence that implicates multiple genes—including reduced expression of a membrane flippase (ATP11A), and increased expression of a mucin (MUC1)—in critical disease. Mendelian randomization provides evidence in support of causal roles for myeloid cell adhesion molecules (SELE, ICAM5 and CD209) and the coagulation factor F8, all of which are potentially druggable targets. Our results are broadly consistent with a multi-component model of COVID-19 pathophysiology, in which at least two distinct mechanisms can predispose to life-threatening disease: failure to control viral replication; or an enhanced tendency towards pulmonary inflammation and intravascular coagulation. We show that comparison between cases of critical illness and population controls is highly efficient for the detection of therapeutically relevant mechanisms of disease

Influence of steam-calcination and acid leaching treatment on the VGO hydrocracking performance of faujasite zeolite

The effect of hydrothermal treatment and mild acid leaching on the physico-chemical properties of zeolite Y and its vacuum gas oil hydrocracking performance was investigated. Ultra-stabilized Y (USY) zeolites were obtained by steam-calcination at 500, 600 and 700 °C. Steam-treated zeolites were further subjected to a mild acid leaching treatment. The zeolite samples were characterized by XRD, elemental analysis, XPS, N2 adsorption, 29Si and 27Al NMR and FTIR spectroscopy of adsorbed pyridine. Steam-calcination resulted in dealumination and with increasing severity the micropore surface area and the framework Al content decreased. At the same time, the Al content at the zeolite crystal surface increased. Acid leaching improved the pore accessibility and acid properties due to the extraction of extraframework Al species (EFAl). NiMoP-based hydrocracking catalysts were prepared from the modified USY zeolites with alumina as binder. Hydrocracking activities correlated with the acidity of the zeolites. Too severe steam treatment led to depopulation of acid sites and lowered the hydrocracking performance. Hydrocracking catalysts based on the acid leached zeolites were more active than the ones based on the corresponding steam-treated zeolites. It is based on the removal of agglomerated extraframework Al species that block the access to some of the micro- and mesopores. This study points out that, aside from the acidity, also other parameters such as pore accessibility and the presence of EFAl have considerable influence on the hydrocracking of the heavy molecules in a gas oil feed

Influence of steam-calcination and acid leaching treatment on the VGO hydrocracking performance of faujasite zeolite

The effect of hydrothermal treatment and mild acid leaching on the physico-chemical properties of zeolite Y and its vacuum gas oil hydrocracking performance was investigated. Ultra-stabilized Y (USY) zeolites were obtained by steam-calcination at 500, 600 and 700 °C. Steam-treated zeolites were further subjected to a mild acid leaching treatment. The zeolite samples were characterized by XRD, elemental analysis, XPS, N2 adsorption, 29Si and 27Al NMR and FTIR spectroscopy of adsorbed pyridine. Steam-calcination resulted in dealumination and with increasing severity the micropore surface area and the framework Al content decreased. At the same time, the Al content at the zeolite crystal surface increased. Acid leaching improved the pore accessibility and acid properties due to the extraction of extraframework Al species (EFAl). NiMoP-based hydrocracking catalysts were prepared from the modified USY zeolites with alumina as binder. Hydrocracking activities correlated with the acidity of the zeolites. Too severe steam treatment led to depopulation of acid sites and lowered the hydrocracking performance. Hydrocracking catalysts based on the acid leached zeolites were more active than the ones based on the corresponding steam-treated zeolites. It is based on the removal of agglomerated extraframework Al species that block the access to some of the micro- and mesopores. This study points out that, aside from the acidity, also other parameters such as pore accessibility and the presence of EFAl have considerable influence on the hydrocracking of the heavy molecules in a gas oil feed

Effect of USY zeolite chemical treatment with ammonium nitrate on its VGO hydrocracking performance

Chemically modified USY zeolites were obtained by ammonium nitrate (AN) treatment under hydrothermal conditions. AN treatment considerably enhanced the mesopore volume of the parent steam-treated zeolite. This treatment also caused the creation of extraframework species of weak acid nature. NiMoP-based hydrocracking catalysts were prepared using the modified zeolites and evaluated in the hydrocracking of a heavy vacuum gas oil (VGO). Hydrocracking activity results indicate that, although AN treatment significantly develops mesoporosity in the parent steam-treated USY zeolite, this single treatment was not efficient to enhance the accessibility of VGO compounds to the acid sites. However, the catalysts based on AN-treated zeolites showed significantly higher middle distillates yields than the one based on a steam-treated zeolite. The creation of an amorphous phase at the mesopore walls and the external surface of the zeolite crystals was argued to support this observation. Mild Na2H2-EDTA treatment to an AN-treated zeolite showed to be beneficial to improve the hydrocracking activity. This was attributed to the enhanced access to acid sites after the removal of polymerized extraframework aluminum species (EFAl). Consequently, a modification strategy of USY zeolites that includes AN treatments is proposed to develop catalysts with enhanced middle distillates selectivity in the hydrocracking of real feedstocks

Effect of proximity and support material on deactivation of bifunctional catalysts for the conversion of synthesis gas to olefins and aromatics

Synthesis gas conversion to short olefins and aromatics using bifunctional catalysts has gained much attention in recent years. Here, we study the interaction between the components of bifunctional catalysts to design a more stable catalyst system. Mixing α-alumina supported iron (-carbide) promoted with sodium and sulfur with an H-ZSM-5 zeolite to convert synthesis gas to aromatics and short olefins we observed selectivity loss of the iron (-carbide) catalyst as well as the acid function. This was displayed by increasing methane and decreasing aromatics selectivity when the two individual catalysts were mixed in close proximity. We introduced different approaches to understand this selectivity related deactivation. Larger spatial separation of the iron and zeolite allowed a more stable system with constant methane and aromatics selectivity. Alternatively, iron supported on carbon nano tubes mixed with the zeolite in close proximity did not display selectivity related deactivation. We conclude that the selectivity loss was caused by migration of sodium ions that were used next to sulfur as promoters on the iron catalyst over the α-alumina support to the zeolite, which was supported by XPS model experiments. This migration seems hindered on carbon supported iron catalysts