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In this work the activity of ruthenium decorated carbon foam (Ru/CF) catalyst was studied in three phase hydrogenation reaction of d-xylose to d-xylitol. The developed catalyst was characterized by using scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, inductively coupled plasma optical emission spectrometry and nitrogen adsorption–desorption measurement. Kinetic measurements were carried out in a laboratory scale pressurized reactor (Parr®) assisted by SpinChem® rotating bed reactor (SRBR), at pre-defined conditions (40–60 bar H2 and 100–120 °C). The study on the influence of reaction conditions showed that the conversion rate and selectivity of hydrogenation reaction of d-xylose was significantly affected by temperature. These results have been proved by a competitive kinetics model which was found to describe the behavior of the novel system (Ru/CF catalyst used together with the SRBR) very well. Besides, it was revealed that the catalytic activity as well as the stability of our Ru/CF-SRBR is comparable with the commercial ruthenium decorated carbon catalyst (Ru/AC) under identical reaction conditions. Moreover, all steps from catalyst preparation and catalyst recycling as well as catalytic testing can be performed in an easy, fast and elegant manner without any loss of materials. Briefly, the developed Ru/CF catalyst used together with the SRBR could be used an excellent alternative for the conventional Raney nickel catalyst in a slurry batch reactor and offers an attractive concept with obvious industrial applicability.

Biobased carbon materials (BBC) obtained from Norway spruce (Picea abies Karst.) bark was produced by single-step chemical activation with ZnCl2 or KOH, and pyrolysis at 800 °C for one hour. The chemical activation reagent had a significant impact on the properties of the BBCs. KOH-biobased carbon material (KOH-BBC) had a higher specific surface area (SBET), equal to 1067 m2 g−1, larger pore volume (0.558 cm3 g−1), more mesopores, and a more hydrophilic surface than ZnCl2-BBC. However, the carbon yield for KOH-BBC was 63% lower than for ZnCl2-BBC. Batch adsorption experiments were performed to evaluate the ability of the two BBCs to remove two dyes, reactive orange 16 (RO-16) and reactive blue 4 (RB-4), and treat synthetic effluents. The general order model was most suitable for modeling the adsorption kinetics of both dyes and BBCs. The equilibrium parameters at 22 °C were calculated using the Liu model. Upon adsorption of RO-16, Qmax was 90.1 mg g−1 for ZnCl2-BBC and 354.8 mg g−1 for KOH-BBC. With RB-4, Qmax was 332.9 mg g−1 for ZnCl2-BBC and 582.5 mg g−1 for KOH-BBC. Based on characterization and experimental data, it was suggested that electrostatic interactions and hydrogen bonds between BBCs and RO-16 and RB-4 dyes played the most crucial role in the adsorption process. The biobased carbon materials showed high efficiency for removing RO-16 and RB-4, comparable to the best examples from the literature. Additionally, both the KOH- and ZnCl2-BBC showed a high ability to purify two synthetic effluents, but the KOH-BBC was superior.

Herein we report a 3D heterostructure comprising a hierarchical macroporous carbon foam that incorporates mesoporous carbon nanotubes decorated with cobalt oxide nanoparticles as an unique and highly efficient electrode material for the oxygen evolution reaction (OER) in electrocatalytic water splitting. The best performing electrode material showed high stability after 10 h, at constant potential of 1.7 V vs. RHE (reversible hydrogen electrode) in a 0.1 M KOH solution and high electrocatalytic activity in OER with low overpotential (0.38 V vs RHE at 10 mA cm −2 ). The excellent electrocatalytic performance of the electrode is rationalized by the overall 3D macroporous structure and with the firmly integrated CNTs directly grown on the foam, resulting in a large specific surface area, good electrical conductivity, as well as an efficient electrolyte transport into the whole electrode matrix concurrent with an ability to quickly dispose oxygen bubbles into the electrolyte. The eminent properties of the three-dimensional structured carbon matrix, which can be synthesized through a simple, scalable and cost effective pyrolysis process show that it has potential to be implemented in large-scale water electrolysis systems.

In the present work electrically conductive, flexible, lightweight carbon sponge materials derived from open-pore structure melamine foams are studied and explored. Hydrophobic and hydrophilic surface properties - depending on the chosen treatment conditions - allow the separation and storage of liquid chemical compounds. Activation of the carbonaceous structures substantially increases the specific surface area from ~4 m 2 g −1 to ~345 m 2 g −1 , while retaining the original three-dimensional, open-pore structure suitable for hosting, for example, Ni catalyst nanoparticles. In turn the structure is rendered suitable for hydrogenating acetone to 2-propanol and methyl isobutyl ketone as well for growing hierarchical carbon nanotube structures used as electric double-layer capacitor electrodes with specific capacitance of ~40 F/g. Mechanical stress-strain analysis indicates the materials are super-compressible (>70% volume reduction) and viscoelastic with excellent damping behavior (loss of 0.69 ± 0.07), while piezoresistive measurements show very high gauge factors (from ~20 to 50) over a large range of deformations. The cost-effective, robust and scalable synthesis - in conjunction with their fascinating multifunctional utility - makes the demonstrated carbon foams remarkable competitors with other three-dimensional carbon materials typically based on pyrolyzed biopolymers or on covalently bonded graphene and carbon nanotube frameworks.

In this study, we report a 3D structured carbon foam electrode assembled from a bi-functional NiCo catalyst, carbon nanotubes (CNT), and a monolith 3D structured carbon foam (CF) as a highly active and stable electrode for oxygen evolution reaction (OER) and methanol oxidation reaction (MOR). When the NiCo@CNTs/CF electrode was used as an anode in OER, after the anodization step, the electrode required a small overpotential of 320 mV to reach the current density of 10 mA cm−2 and demonstrated excellent stability over a long testing time (total 30 h) in 1 M KOH. The as-prepared NiCo@CNTs/CF electrode also exhibited a good performance towards methanol oxidation reaction (MOR) with high current density, 100 mA cm−2 at 0.6 V vs. Ag/AgCl, and good stability in 1 M KOH plus 0.5 M CH3OH electrolyte. The NiCo@CNTs/CF catalyst/electrode provides a potential for application as an anode in water electrolysis and direct methanol fuel cells.

Since 1979, the refugees from Viet Nam have become a more and more visible part of the Canadian population. Similarly, Vietnamese students have become increasingly more noticeable in schools across the country and notably in large urban areas. One of the major difficulties encountered in interactions between these newcomers and Canadians is clearly communication in the broadest sense of the term and more particularly at both the verbal and nonverbal level. While there is a growing literature on teaching English to Vietnamese, little has been written about their nonverbal communication and probably nothing on their sensitivity to Canadian nonverbal behaviours. This study is an attempt to help fill this gap. Its primary focus is on the sensitivity of Vietnamese students in Metro Toronto to facial expressions of emotions of West-Indians and white Anglo-Canadians as well as to the latter's emblematic gestures. In addition, it also attempts to generate an inventory of Vietnamese emblematic gestures currently in use in the Canadian setting. The study was designed to determine whether factors like gender, length of residency or race affect the participants' decoding abilities as well as to test the robustness of the pan-cultural theory in non-verbal communication. Generally speaking, length of residence and to a certain extent, race were significant factors in the participants' decoding performances. On the other hand, the gender factor was not significant at all. This result contradicts the \"female advantage\" mentioned in the literature. On the theoretical level, the findings lend support to both the universality and culture-specific hypotheses with the latter in a more dominant position in the case of gestures. The Vietnamese Gesture Inventory, as generated by this study, also highlights the impact of cultural encounters and the possibility of having more and more universals in human communication. The implications of this study in terms of training, promoting interactions among different cultural groups, along with its limitations and directions for future research are discussed.

A variety of methods have been utilized in order to detect the occurrence of a single electron transfer pathway in the reduction of alkyl halides by LiAlH(,4), AlH(,3) and LiEt(,3)BH, i.e. (1) product studies of reduction of cyclizable alkyl halides containing the 5-hexenyl group, (2) trapping of intermediate radicals by dicyclohexylphosphine and other trapping agents and (3) direct EPR observation of the trityl radical in the reduction of trityl bromide by LiEt(,3)BH. The extent of electron transfer was found to be a function of the solvent, the substrate, the leaving group, and the hydride agent. For alkyl iodide, and to a much lesser extent bromides, electron transfer was found to be the major reaction pathway; however, no evidence for electron transfer was found for the corresponding chlorides and tosylates. New cyclizable alkyl halide probes, (endo)-5-(2'haloethyl)-2-norbornenes have been synthesized, and their corresponding radical generated by reaction with tri-n-butyltin hydride in the presence of AIBN was found to cyclize substantially faster than the often used 5-hexenyl halide probes. This new radical probe was also used in the reactions with sodium, magnesium, sodium naphthalenide, lithium aluminum hydride, (trimethylstannyl)sodium and lithium isopropyl thiolate which was found to produce both straight-chain and cyclized products indicating radical intermediates in such reactions. The reaction of t-Butyllithium with primary and secondary cyclizable alkyl halides has been studied in detail with emphasis on the effect of solvent, temperature and added complexing agents (TMEDA, HMPA and 18-crown-6). All evidence indicates that the reaction proceeds by an electron transfer process involving radical intermediates for the bromides and the iodides. However, no evidence for electron transfer was found for the corresponding chlorides. The reaction of a variety of nucleophiles with optically active alkyl halide probes has been studied in detail. The extent of electron transfer was found to be a function of the solvent, the substrate, the leaving group, and the nucleophile. Reactions of optically alkyl iodides, bromides with nucleophiles were found to be much less stereospecific than the corresponding reactions of chlorides or tosylates indicating intermediate radical formation in the reaction of the secondary iodides and bromides.

This study aimed to compare the chemical composition and antimicrobial activity of essential oils obtained from the rhizomes and leaves of Conamomum pierreanum (Zingiberaceae), and to evaluate interactions of selected constituents with microbial targets using molecular docking and molecular dynamics simulations. Gas chromatography–mass spectrometry (GC-MS) identified 21 compounds in the rhizome essential oil (EO) and 10 in the leaf EO of C. pierreanum, with 1,8-cineole (54.44% and 75.73%, respectively) as the predominant constituent. Notably, the rhizome EO was uniquely characterized by epi-γ-eudesmol (3.47%) and isobornyl acetate (3.39%), which were absent in the leaf oil. In vitro assays revealed that the rhizome EO possessed stronger antibacterial and antifungal activities (MIC = MBC = MFC = 0.4%) compared to the leaf EO (0.8%) against Staphylococcus aureus and Candida albicans. Molecular docking identified epi-γ-eudesmol as the most potential ligand, exhibiting remarkably high binding affinities for S. aureus DHFR (−8.1 kcal/mol) and C. albicans CYP51 (−8.5 kcal/mol), significantly outperforming the major constituents. A total of 100 ns molecular dynamics simulations and MM-PBSA analysis further confirmed the structural stability and energetically favorable binding of these complexes, with epi-γ-eudesmol maintaining a low average RMSD (<1.2 Å) throughout the simulation. The enhanced efficacy of the rhizome oil is attributed to the synergistic contribution of these high-affinity minor constituents. These findings suggest that C. pierreanum rhizome EO may serve as a potential source of bioactive compounds for antimicrobial applications, warranting further investigation.

Wound healing is a recovering process of damaged tissues by replacing dysfunctional injured cellular structures. Natural compounds for wound treatment have been widely used for centuries. Numerous published works provided reviews of natural compounds for wound healing applications, which separated the approaches based on different categories such as characteristics, bioactivities, and modes of action. However, current studies provide reviews of natural compounds that originated from only plants or animals. In this work, we provide a comprehensive review of natural compounds sourced from both plants and animals that target the different bioactivities of healing to promote wound resolution. The compounds were classified into four main groups (i.e., anti-inflammation, anti-oxidant, anti-bacterial, and collagen promotion), mostly studied in current literature from 1992 to 2022. Those compounds are listed in tables for readers to search for their origin, bioactivity, and targeting phases in wound healing. We also reviewed the trend in using natural compounds for wound healing.