Low-Cost Ni-W Catalysts Supported on Glucose/Carbon Nanotube Hybrid Carbons for Sustainable Ethylene Glycol Synthesis.

The production of ethylene glycol (EG) from cellulose has garnered significant attention in recent years as an attractive alternative to fossil fuels due to the potential of cellulose as a renewable and sustainable feedstock. In this work, to the best of our knowledge, a series of low-cost Ni-W bimetallic catalysts supported on glucose/carbon nanotube hybrid carbons were synthesised for the first time and employed to transform cellulose into EG. Two different strategies were combined for the preparation of the carbons: the activation and addition of carbon nanotubes (CNTs) to obtain a hybrid material (AG-CNT).

Surgical treatment for obstructive sleep apnea: effect on sleep architecture.

Purpose: Investigate the effect of surgical treatment of obstructive sleep apnea syndrome (OSA) on sleep architecture.

Methods: Observational retrospective analysis of polysomnographic data of adults diagnosed with OSA, submitted to surgical treatment. Median (25-75th percentile) was used to present the data.

Unilateral vocal fold paralysis as a port complication.

Unilateral vocal fold paralysis (UVFP) is a frequent finding in otorhinolaryngology practice, but its occurrence as a port complication was very rarely described in English Literature. The authors report a 55-year-old woman with a pancreatic adenocarcinoma who presented a left vocal fold paralysis that occurred concurrently with a venous thrombosis of the left subclavian vein, where a totally implantable venous-access had been previously placed. Although the patient's oncologic disease, that could mislead to a neoplastic cause of the UVFP, the authors came across with an unusual etiology and to their best knowledge, it is the first case of irreversible UVFP associated with onsite thrombosis of the vessel where a port was implanted.

Highly N-Selective Activated Carbon-Supported Pt-In Catalysts for the Reduction of Nitrites in Water.

The catalytic reduction of nitrites over Pt-In catalysts supported on activated carbon has been studied in a semi-batch reactor, at room temperature and atmospheric pressure, and using hydrogen as the reducing agent. The influence of the indium content on the activity and selectivity was evaluated. Monometallic Pt catalysts are very active for nitrite reduction, but the addition of up to 1 wt% of indium significantly increases the nitrogen selectivity from 0 to 96%.

Auditory Brainstem Response in Preterm Infants in the Neonatal Intensive Care Unit.

Objective: To analyze auditory brainstem response (ABR) findings of preterm and term infants in the neonatal intensive care unit (NICU) with perinatal problems.

Study Design: Case series with chart review.

Setting: Secondary care hospital.

Catalytic and Photocatalytic Nitrate Reduction Over Pd-Cu Loaded Over Hybrid Materials of Multi-Walled Carbon Nanotubes and TiO.

TiO and carbon nanotube-TiO hybrid materials synthesized by sol-gel and loaded with 1%Pd-1%Cu (%.) were tested in the catalytic and photocatalytic reduction of nitrate in water in the presence of CO (buffer) and H (reducing agent). Characterization of the catalysts was performed by UV-Vis and fluorescence spectroscopy, X-ray diffraction, temperature programed reduction, N adsorption, and electron microscopy.

Insights into the effect of the catalytic functions on selective production of ethylene glycol from lignocellulosic biomass over carbon supported ruthenium and tungsten catalysts.

The one-pot conversion of cellulose to ethylene glycol (EG) was investigated using a combination of a ruthenium catalyst supported on carbon nanotubes modified with nitric acid (Ru/CNT) and a tungsten catalyst supported on commercial non-treated carbon nanotubes (W/CNT). This physical mixture allowed to obtain an EG yield of 41% in just 5 h at 205 °C and 50 bar of H, which overcame the result obtained using a Ru-W bimetallic catalyst supported on commercial carbon nanotubes (35%) under the same conditions. Tissue paper, a potential waste cellulosic material, and eucalyptus were also tested under the same conditions and EG yields of 34 and 36%, respectively, were attained over the aforementioned catalytic physical mixture.

Zero-valent iron supported on nitrogen-doped carbon xerogel as catalysts for the oxidation of phenol by fenton-like system.

Nitrogen-free and nitrogen-doped carbon xerogel materials, from urea and melamine precursors, were prepared at different pH and evaluated as adsorbents/catalysts in the removal of phenol. Then, zero-valent iron (ZVI) was supported on these carbon xerogel materials and its activity was again evaluated for phenol removal by adsorption and catalytic wet peroxide oxidation (CWPO). The prepared samples were characterized by N adsorption at -196°C, pH at the point of zero charge (pH) and elemental analysis.

Simultaneous catalytic conversion of cellulose and corncob xylan under temperature programming for enhanced sorbitol and xylitol production.

Sorbitol and xylitol yields can be improved by converting cellulose and xylan simultaneously, due to a synergetic effect between both substrates. Furthermore, both yields can be greatly enhanced by simply adjusting the reaction conditions regarding the optimum for the production of each product, since xylitol (from xylan) and sorbitol (from cellulose) yields are maximized when the reaction is carried out at 170 and 205°C, respectively. Therefore, the combination of a simultaneous conversion of cellulose and xylan with a two-step temperature approach, which consists in the variation of the reaction temperature from 170 to 205°C after 2h, showed to be a good strategy for maximizing the production of sorbitol and xylitol directly from mixture of cellulose and xylan.

Direct catalytic production of sorbitol from waste cellulosic materials.

Cotton wool, cotton textile, tissue paper and printing paper, all potential waste cellulosic materials, were directly converted to sorbitol using a Ru/CNT catalyst in the presence of H and using only water as solvent, without any acids. Conversions up to 38% were attained for the raw substrates, with sorbitol yields below 10%. Ball-milling of the materials disrupted their crystallinity, allowing reaching 100% conversion of cotton wool, cotton textile and tissue paper after 4h, with sorbitol yields around 50%.

Effect of cobalt loading on the solid state properties and ethyl acetate oxidation performance of cobalt-cerium mixed oxides.

Cobalt-cerium mixed oxides were prepared by the wet impregnation method and evaluated for volatile organic compounds (VOCs) abatement, using ethyl acetate (EtAc) as model molecule. The impact of Co content on the physicochemical characteristics of catalysts and EtAc conversion was investigated. The materials were characterized by various techniques, including N adsorption at -196°C, scanning electron microscopy (SEM), X-ray diffraction (XRD), H-temperature programmed reduction (H-TPR) and X-ray photoelectron spectroscopy (XPS) to reveal the structure-activity relationship.

How to facilitate early diagnosis of CNS involvement in malignant lymphoma.

Making the diagnosis of secondary CNS involvement in lymphoma can be difficult due to unspecific signs and symptoms, limited accessibility of brain/myelon parenchyma and low sensitivity and/or specifity of imaging and cerebrospinal fluid (CSF) examination currently available. Areas covered: MRI of the total neuroaxis followed by CSF cytomorphology and flow cytometry are methods of choice when CNS lymphoma (CNSL) is suspected. To reduce the numerous pitfalls of these examinations several aspects should be considered.

CO oxidation over gold supported on Cs, Li and Ti-doped cryptomelane materials.

Cryptomelane-type manganese oxides were synthesized by redox reaction under acid and reflux conditions. Different metals (cesium, lithium and titanium) were incorporated into the tunnel structure by the ion-exchange technique. Gold was loaded onto these materials (1wt%) by a double impregnation method.

Ethyl Acetate Abatement on Copper Catalysts Supported on Ceria Doped with Rare Earth Oxides.

Different lanthanide (Ln)-doped cerium oxides (Ce0.5Ln0.5O1.

Ozonation of bezafibrate over ceria and ceria supported on carbon materials.

Two catalysts containing ceria dispersed on the surface of multi-walled carbon nanotubes and activated carbon were investigated as ozonation catalysts for the mineralization of bezafibrate (BZF). The results were compared with those obtained in the absence of the catalyst and in the presence of the parent carbon materials, as well as in the presence of ceria (CeO2). Carbon materials containing ceria showed an interesting catalytic effect.

Process design for wastewater treatment: catalytic ozonation of organic pollutants.

Emerging micropollutants have been recently the target of interest for their potential harmful effects in the environment and their resistance to conventional water treatments. Catalytic ozonation is an advanced oxidation process consisting of the formation of highly reactive radicals from the decomposition of ozone promoted by a catalyst. Nanocarbon materials have been shown to be effective catalysts for this process, either in powder form or grown on the surface of a monolithic structure.

Nitrate reduction over a Pd-Cu/MWCNT catalyst: application to a polluted groundwater.

The influence of the presence of inorganic and organic matter during the catalytic reduction of nitrate in a local groundwater over a Pd-Cu catalyst supported on carbon nanotubes was investigated. It was observed that the catalyst performance was affected by the groundwater composition. The nitrate conversion attained was higher in the experiment using only deionized water as solvent than in the case of simulated or real groundwater.

Catalytic ozonation of sulphamethoxazole in the presence of carbon materials: catalytic performance and reaction pathways.

Two carbon materials (multi-walled carbon nanotubes, MWCNTs, and activated carbon) were investigated as ozonation catalysts for the mineralization of the antibiotic sulphamethoxazole (SMX). MWCNTs presented a higher catalytic performance than activated carbons, which was justified by their differences in surface chemistry and by the higher internal mass transfer resistances expected for activated carbons. 3-Amino-5-methylisoxazole and p-benzoquinone were detected as primary products of single and catalytic ozonation of SMX, whereas oxamic, oxalic, pyruvic and maleic acids were identified as refractory final oxidation products.

Catalytic ozonation of metolachlor under continuous operation using nanocarbon materials grown on a ceramic monolith.

The catalytic ozonation of the herbicide metolachlor (MTLC) was tested using carbon nanomaterials as catalysts. Multiwalled carbon nanotubes were used in semi-batch experiments and carbon nanofibres grown on a honeycomb cordierite monolith were tested in continuous experiments. The application of the carbon catalyst was shown to improve the mineralization degree of MTLC and to decrease the toxicity of the solution subject to ozonation.

Catalytic ozonation of oxalic acid using carbon nanofibres on macrostructured supports.

Carbon nanofibres (CNFs) were grown on different macrostructured supports such as cordierite monoliths, carbon felts and sintered metal fibres. The resulting composites exhibited excellent resistance to attrition/corrosion and its porosity is mainly due to mesoporous structures. The CNF/structured materials were tested in the ozonation of oxalic acid in a conventional semi-batch reactor after being crushed to powder form, and in a newly designed reactor that may operate in semi-batch or continuous operation.

Composites of manganese oxide with carbon materials as catalysts for the ozonation of oxalic acid.

Manganese oxide and manganese oxide-carbon composites were prepared and tested as catalysts for the removal of oxalic acid by ozonation. Their performances were compared with the parent carbon material (activated carbon or carbon xerogel) used to prepare the composites. Oxalic acid degradation by carbon materials is slower than that attained with manganese oxide or manganese oxide-carbon composites.

Effect of support and pre-treatment conditions on Pt-Sn catalysts: application to nitrate reduction in water.

The effect of the support (activated carbon or titanium dioxide) on the catalytic activity and selectivity to nitrogen of Pt-Sn catalysts in nitrate reduction was studied. The effects of the preparation conditions and the Pt:Sn atomic ratio were also evaluated. It was observed that the support plays an important role in nitrate reduction and that different preparation conditions lead to different catalytic activities and selectivities.

Mixture effects during the oxidation of toluene, ethyl acetate and ethanol over a cryptomelane catalyst.

The catalytic oxidation of two-component VOC mixtures (ethanol, ethyl acetate and toluene) was studied over cryptomelane. Remarkable mixture effects were observed on the activity and the selectivity. Toluene inhibits both ethyl acetate and ethanol oxidation, this effect being more evident in the case of ethyl acetate.