Designing biomass lignins for the biorefinery

4 páginas.- 3 figuras. 17 referencias.- Comunicación oral presentada en el 16th European Workshop on Lignocellulosics and Pulp (EWLP) Gothenburg, Sweden, June 28 – July 1, 2022As ever more component monomers are discovered, lignin can no longer be regarded as deriving from just the three canonical monolignols. Pathway intermediates and additional products of truncated biosynthesis are now established lignin monomers. The array of acylated monolignols continues to expand. Game-changing findings have demonstrated that phenolics from alternative pathways, including flavonoids and hydroxystilbenes, are also involved in lignification, expanding the traditional concept. Beyond the basic science intrigue, these findings propound exciting new avenues for valorizing lignins, or for producing more readily extractable or depolymerizable lignins, in crop and bioenergy plants.We further acknowledge lots of colleagues and collaborators, and funding from the Swiss National Science Foundation (Synergia) grant # CRS115_180258, and the DOE Great Lakes Bioenergy Research Center (DOE BER Office of Science DE-SC0018409).N

Direct hydrothermal synthesis of palladium-incorporated silicate-structured mesoporous catalysts

Pd-Si-structured novel mesoporous nanocomposite catalytic materials, having quite high Pd/Si ratios, were synthesized by an acidic direct hydrothermal synthesis route. The nanocomposite catalytic materials were then characterized by XRD, XPS, EDS, nitrogen adsorption, and SEM techniques. Unlike MCM-41, the XRD patterns indicated a rather wide d((100)) band at a 2 theta value of about 1.9. The materials, with very high Pd/Si wt ratios between 1.43 and 2.66, were synthesized and had BJH surface area values between 600 and 200 m(2)/g. The pore size distributions of these materials were also quite narrow, indicating pores between 2 and 7 nm

Effects of synthesis conditions on the structure of Pd incorporated MCM-41 type mesoporous nanocomposite catalytic materials with high Pd/Si ratios

Pd incorporated MCM-41 type mesoporous catalytic materials were prepared by the basic and the acidic direct hydrothermal synthesis procedures using different Pd sources. Also, nanocomposite materials containing Pd nanoballs within the mesopores of the host MCM-41 were prepared following an impregnation procedure. Basic direct hydrothermal synthesis route was shown to be highly successful for the production of high surface area (over 1000 m(2)/g) Pd-MCM-41 nanocomposite materials with very high Pd/Si wt. ratios, reaching to 0.44. The nanocomposite material produced following the acidic route gave a product with a wider pore size distribution and lower surface area (about 650 m(2)/g). PdCl2 and K2PdCl4 were shown to be better Pd sources than Pd(NH3)(4)(NO3)(2) for the incorporation of Pd into the MCM-41 lattice. The surface area and the pore volume of the host MCM-41 decreased about 20% by the formation of Pd grains in the mesopores of host MCM-41, for the material prepared by the impregnation procedure and containing a Pd/Si wt. ratio of 0.12. (c) 2006 Elsevier Inc. All rights reserved

A fatal rabies case and experiences of a mass post exposure prophylaxis among healthcare workers

NATe aimed to monitor the adverse effects (AE) and efficacy of post exposure prophylaxis (PEP) in health care workers (HCWs) exposed to a rabies patient. In this study 109 HCWs and eight household contacts were PEP candidates. Contact persons without infection control precautions were in Group I (high risk-82 cases). HCWs indirectly exposed to environmental surfaces were classified in Group 11 (low risk-35 cases). PEP schedule was rabies vaccine (RBV) + equine rabies immunoglobulin (eRIG) in Group I and only RBV in Group II. Local and systemic AE were observed in all cases. Efficacy of post exposure prophylaxis (PEP) was determined by rabies development in a six month follow-up. 585 doses of RBV have been used in 117 cases and eRIG has been used in 82 cases. 32 Nurses (39%); 22 emergency medicine technicians (26.8%); 12 doctors (14%); six laboratory technicians (0.07%); six radiology technicians (0.07%); four cleaners (0.05%) were in Group I (82 cases), respectively. One doctor, laboratory technician, nurse and radiology technician (0.02%); two emergency medicine technicians (0.04%) and nine cleaners (25.7%) were in Group II (35 cases), respectively. Routes of transmission were blood in five (0.06%); saliva in 14 (17%); sweat in 50 (61%); CSF/serum in five (0.06%); sexual intercourse in one (0.01%); personal equipment in seven (0.09%) in Group I, respectively. Indirect contact was the only route in Group II. The most common local and systemic AE were seen in Group I; pain at injection side (19 cases) and fever (13 cases). Both of them showed statistically significant difference (P<0.05). Allergic rash has been seen at only one case. PEP failed in one case where the possible exposure way was sexual intercourse. PEP is the safest way to prevent rabies. Infection control precautions were still not enough applied. eRIGs are also safe and have rare AE

Epidemiologic and microbiologic evaluation of nosocomial infections associated with Candida spp in children: A multicenter study from Istanbul, Turkey

Background: The purpose of this study was to establish species distribution of Candida isolates from pediatric patients in Istanbul, Turkey, and to determine risk factors associated with nosocomial Candida infections

Synthesis gas conversion over Rh-based catalysts promoted by Fe and Mn

FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICORh/SiO2 catalysts promoted with Fe and Mn are selective for synthesis gas conversion to oxygenates and light hydrocarbons at 523 K and 580 psi. Selective anchoring of Fe and Mn species on Rh nanoparticles was achieved by controlled surface reactions and w7745504563FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO2015/20477-12015/23900-2309373/2014-

PtMo Bimetallic Catalysts Synthesized by Controlled Surface Reactions for Water Gas Shift

Supported PtMo bimetallic catalysts were prepared by controlled surface reactions (CSR) and studied for water gas shift (WGS) at 543 K. Carbon and silica supports were used for the preparation of monometallic Pt catalysts, and Mo was deposited onto these catalysts by reaction with cycloheptatriene molybdenum tricarbonyl ((C₇H₈)­Mo­(CO)₃). Catalysts were characterized by CO chemisorption, inductively coupled plasma-atomic emission spectroscopy (ICP-AES), STEM/EDS, and XAS analysis. We report that carbon-supported Pt nanoparticles are saturated with Mo species at a Mo:Pt atomic ratio of 0.32. Molybdenum has a strong promotional effect in these catalysts, increasing the TOF by up to a factor of more than 4000. Silica-supported catalysts were found to be more active, but the TOF promotional effect of Mo was smaller than for the carbon-supported catalysts at 15. EDS analyses and activity studies showed that the formation of bimetallic catalysts was therefore more efficient using the carbon support. The active sites for WGS are suggested to be at the interface between Pt atoms and Mo moieties that are possibly in an oxidized form

Six-year distribution pattern of hepatitis C virus in Turkey: a multicentre study

Hepatitis C infection is a public health problem. The aim of this retrospective study was to determine the distribution of hepatitis C virus (HCV) genotypes in seven regions of Turkey, by evaluating 7002 patients with chronic HCV in a six-year period. During the 2009-2014 period, serum/plasma samples from 7002 new consecutive HCV RNA positive patients were collected. The female patients were 3867 (55.2%). The genotype distribution of HCV patiens was evaluated by ages and years. Statistical analysis was performed by using the Mann-Whitney test and the chi(2) analysis. During the six-year period, genotype 1b was the most common genotype (67.7%) followed by untypeable genotype 1 (7.7%), genotype 4 (7.3%) and genotype 3 (6.7%). In 2014, genotype 3 was the second most common one (11.3%) and genotype 4 was the third most common one (9.8%). In the group with <25 years old patients, genotype 1b was most common (78.48%, 62/79) between the years of 2009 and 2011, whereas genotype 3 (34.8%, 86/247), between the years of 2012 and 2014. Genotype 1b was the most common in the groups between 26 and 35 years, 36 and 45 years, 46 and 55 years, 56 and 65 years. The rate of genotype 3 was increased from 4.78% to 10.06% and the rate of genotype 4 was increased from 1.3% to 3.84%, from 2009-2011 to 2012-2014. In recent years, genotypes 3 and 4 have gained importance. New therapeutic strategies and survey studies may be required for the modified HCV genotype pattern

Catalytic hydrogenation of dihydrolevoglucosenone to levoglucosanol with a hydrotalcite/mixed oxide copper catalyst

Levoglucosanol (LGOL) is a critical intermediate for the bio-based production of hexane-1,2,5,6-tetrol, 1,2,6-hexanetriol, and 1,6-hexanediol. Here we report on the aqueous-phase hydrogenation of cellulose-derived dihydrolevoglucosenone (Cyrene™) to LGOL using a calcined and reduced heterogeneous copper/hydrotalcite/mixed oxide catalyst, denoted as Cu8/MgAlOx-HP. The turnover frequency for LGOL conversion over this copper-containing catalyst is equal to 0.013 s−1 at 353 K as measured in a flow reactor which is half the one obtained using 0.4 wt% Pd/Al2O3. Moreover, while Cu8/MgAlOx-HP shows a stable activity, the activity of 0.4 wt% Pd/Al2O3 decreases with time-on-stream. Neither Cu- nor Al-leaching is observed (resp. <1 ppb and <1 ppm) but Mg leaching can be seen (5.5 ppm). The latter leaching relates to the acidity of the Cyrene/H2O mixture (pH 3.5–4.5 range), which is due to the occurrence of the geminal diol moiety of Cyrene, an acidic species. In contrast, additional and consecutive oxidation and reduction of the catalyst leads to a gradual decrease in activity over time. Applying still further oxidation/reduction cycles to this catalyst tends to decrease its activity with some overall stabilization being observed from the fourth run onwards. Mg-leaching is shown to change the relative meso-to-macro pore content, but leaves the total pore volume unchanged between the fresh and the spent catalyst. In spite of the high copper loading (8 wt%), small Cu-nanoparticles (2–3 nm) are present over the hydrotalcite/mixed oxide surface of the Cu8/MgAlOx-HP material, and these particles do not aggregate during the hydrogenation reaction