Emerging single-atom catalysts in the detection and purification of contaminated gases.

Single atom catalysts (SACs) show exceptional molecular adsorption and electron transfer capabilities owing to their remarkable atomic efficiency and tunable electronic structure, thereby providing promising solutions for diverse important processes including photocatalysis, electrocatalysis, thermal catalysis, Consequently, SACs hold great potential in the detection and degradation of pollutants present in contaminated gases. Over the past few years, SACs have made remarkable achievements in the field of contaminated gas detection and purification. In this review, we first provide a concise introduction to the significance and urgency of gas detection and pollutant purification, followed by a comprehensive overview of the structural feature identification methods for SACs.

Surfactant-Free Monodispersed Pd Nanoparticles Template for Core-Shell Pd@PdPt Nanoparticles as Electrocatalyst towards Methanol Oxidation Reaction (MOR).

An eco-friendly two-step synthetic method for synthesizing Pd@PdPt/CNTs nanoparticles was introduced and studied for the methanol oxidation reaction. The Pd@PdPt alloy core-shell structure was synthesized by preparing a surfactant-free monodispersed Pd/CNTs precursor through the hydrolysis of tetrachloropalladate (II) ion ([PdCl]) in the presence of carbon nanotubes (CNTs) and the subsequent hydrogen reduction and followed by a galvanic replacement reaction. This method opens up an eco-friendly, practical, and straightforward route for synthesizing monometallic or bimetallic nanoparticles with a clean surfactant-free electrocatalytic surface.

Mesoporous Zn/MgO Hexagonal Nano-Plates as a Catalyst for Oil Biodiesel Synthesis.

A novel mesoporous Zn/MgO hexagonal-nano-plate catalyst was synthesized by a simple template-free hydrothermal method and applied in the base-catalyzed transesterification of oil for biodiesel synthesis. The Zn/MgO catalyst calcinated at 873 K exhibited the highest catalytic activity with a yield of 88.7%.

Why is the world not yet ready to use alternative fuel vehicles?

Despite the improvement in technologies for the production of alternative fuels (AFs), and the needs for using more AFs for motor vehicles for the reductions in air pollution and greenhouse gases, the number of alternative fuel vehicles (AFVs) in the global transportation sector has not been increasing significantly (there are even small drops for adapting some AFs through the projections) in recent years and even in the near future with projections to 2050. And gasoline and diesel fuels will remain as the main energy sources for motor vehicles. After reviewing the latest advantages and disadvantages of AFVs, including flexible-fuel, gas, electric, hybrid electric, and fuel cell electric vehicles, it is found that the higher price of AFVs, compared to that of gasoline and diesel vehicles, might be one of the main barriers for their wider adoption.

Reusable Face Masks as Alternative for Disposable Medical Masks: Factors that Affect their Wear-Comfort.

The coronavirus outbreak that commenced at the end of 2019 has led to a dramatic increase in the demand for face masks. In countries that are experiencing a shortage of face masks as a result of panic buying or inadequate supply, reusable fabric masks have become a popular option, because they are often considered more cost-effective and environmentally friendly than disposable medical masks. Nevertheless, there remains a significant variation in the quality and performance of existing face masks; not all are simultaneously able to provide protection against the extremely contagious virus and be comfortable to wear.

Non-polar organic compounds, volatility and oxidation reactivity of particulate matter emitted from diesel engine fueled with ternary fuels in blended and fumigation modes.

The present experimental study aims to examine the impacts of various fueling modes of operation on the particle-phase polycyclic aromatic hydrocarbons (PAHs) and n-alkanes (C16-C30), and volatility and oxidation reactivity of particulate matter (PM) emitted from a diesel engine fueled with a ternary fuel (80% diesel, 5% biodiesel and 15% ethanol (D80B5E15, volume %)) under four engine operating conditions. Four fueling modes, including diesel, blended, fumigation and combined fumigation + blended (F + B) modes were tested using pure diesel fuel for diesel mode and a constant fuel content of D80B5E15 for the blended, fumigation and F + B modes to create the same condition for comparing their impacts on the parameters investigated. The average results illustrate that both blended and fumigation modes can reduce the PAHs (-78.

Effects of engine load and biodiesel content on performance and regulated and unregulated emissions of a diesel engine using contour-plot map.

This experimental study was conducted to explore the favorable and unfavorable conditions which promote or reduce the performance and emissions in a diesel engine, based on six engine loads (5% to 95% load) and five biodiesel contents including B0 (0% waste cooking oil biodiesel and 100% diesel, by volume %), B20, B50, B75 and B100 (pure biodiesel), at a constant engine speed of 1920 rpm. According to the results, the maximum brake specific fuel consumption was recorded at the lowest engine load (5% load) using B100; while the highest brake thermal efficiency was obtained at 80% load for B100. In regard to regulated emissions, the highest engine load (95% load) with diesel fuel was the condition for the formation of maximum CO, smoke opacity, PM mass, total particle number concentration and geometric mean diameter.

Highly water-absorbing silk yarn with interpenetrating network via in situ polymerization.

Silk was modified via in situ polymerization of two monomers acrylamide and sodium acrylate by swelling in an effective LiBr dissolution system. Swelling of natural silks in LiBr solutions of low concentration was clearly observed under optical microscope, and their conformational changes were revealed by X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. Dissolution tests and FTIR spectra of these modified silks suggested the presence of interpenetrating network of polyacrylamide and poly(sodium acrylate) in the silk yarns.

Effective heterogeneous transition metal glycerolates catalysts for one-step biodiesel production from low grade non-refined Jatropha oil and crude aqueous bioethanol.

The utilization of bioethanol as the alcohol source for biodiesel production is more environmentally advantageous over methanol owing to its lower toxicity, lower flammability and its sustainable supply from renewable agricultural resources. However, as the presence of water in crude bioethanol is the critical factor limiting the biodiesel production process, the energy-intensive and costly purification of bioethanol is necessary for biodiesel application. Manganese glycerolate (MnGly) is reported the first time here as a robust heterogeneous catalyst that exhibited over 90% conversion by using aqueous ethanol containing 80 wt.

One-step production of biodiesel from rice bran oil catalyzed by chlorosulfonic acid modified zirconia via simultaneous esterification and transesterification.

Due to the high content (25-50%) of free fatty acid (FFA), crude rice bran oil usually requires a two steps conversion or one step conversion with very harsh condition for simultaneous esterification and transesterification. In this study, chlorosulfonic acid modified zirconia (HClSO3-ZrO2) with strong acidity and durability is prepared and it shows excellent catalytic activity toward simultaneous esterification and transesterification. Under a relative low reaction temperature of 120 °C, HClSO3-ZrO2 catalyzes a complete conversion of simulated crude rice bran oil (refined oil with 40 wt% FFA) into biodiesel and the conversion yield keep at above 92% for at least three cycles.

Over-expression of AtPAP2 in Camelina sativa leads to faster plant growth and higher seed yield.

Background: Lipids extracted from seeds of Camelina sativa have been successfully used as a reliable source of aviation biofuels. This biofuel is environmentally friendly because the drought resistance, frost tolerance and low fertilizer requirement of Camelina sativa allow it to grow on marginal lands. Improving the species growth and seed yield by genetic engineering is therefore a target for the biofuels industry.

Melamine-tainted milk product-associated urinary stones in children.

Background: An outbreak of urinary stones related to consumption of melamine-tainted milk products (MTMP) occurred in China in 2008. The aim of the present study was to evaluate such children to identify their clinical features and risk factors.

Methods: Renal ultrasound was performed for 7328 children who presented to a Sichuan teaching hospital between 13 September and 15 October 2008 due to concern of such stones.