Displaying publications 1 - 20 of 33 in total

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  1. Recent Progress on Advanced Materials for Solid-Oxide Fuel Cells Operating Below 500 °C
    Zhang Y, Knibbe R, Sunarso J, Zhong Y, Zhou W, Shao Z, et al.
    Adv Mater, 2017 Dec;29(48).
    PMID: 28628239 DOI: 10.1002/adma.201700132
    Solid-oxide fuel cells (SOFCs) are electricity generators that can convert the chemical energy in various fuels directly to the electric power with high efficiency. Recent advances in materials and related key components for SOFCs operating at ≈500 °C are summarized here, with a focus on the materials, structures, and techniques development for low-temperature SOFCs, including the analysis of most of the critical parameters affecting the electrochemical performance of the electrolyte, anode, and cathode. New strategies, such as thin-film deposition, exsolution of nanoparticles from perovskites, microwave plasma heating, and finger-like channeled electrodes, are discussed. These recent developments highlight the need for electrodes with higher activity and electrolytes with greater conductivity to generate a high electrochemical performance at lower temperatures.
  2. Complete genome sequence of Bacillus Licheniformis NWMCC0046, a candidate for the laundry industry
    Zhou W, Zeng S, Yu J, Xiang J, Zhang F, Takriff MS, et al.
    J Basic Microbiol, 2023 Feb;63(2):223-234.
    PMID: 36538731 DOI: 10.1002/jobm.202200528
    In this study, selected properties of protease and the complete genome sequence of Bacillus licheniformis NWMCC0046 were investigated, to discover laundry applications and other potential probiotic properties of this strain. Partial characterization of B. licheniformis NWMCC0046 showed that its protease has good activity both in alkaline environments and at low temperatures. Also, the protease is compatible with commercial detergents and can be used as a detergent additive for effective stain removal at low temperatures. The complete genome sequence of B. licheniformis NWMCC0046 is comprised of a 4,321,565 bp linear chromosome with a G + C content of 46.78% and no plasmids. It had 4504 protein-encoding genes, 81 transfer RNA (tRNA) genes, and 24 ribosomal RNA (rRNA) genes. Genomic analysis revealed genes involved in exocellular enzyme production and probiotic properties. In addition, genomic sequence analysis revealed specific genes encoding carbohydrate metabolism pathways, resistance, and cold adaptation capacity. Overall, protease properties show its potential as a detergent additive enzyme. The complete genome sequence information of B. licheniformis NWMCC0046 was obtained, and functional prediction revealed its numerous probiotic properties.
  3. Sustained delivery of prilocaine and lidocaine using depot microemulsion system: in vitro, ex vivo and in vivo animal studies
    Zhang X, Dang M, Zhang W, Lei Y, Zhou W
    Drug Dev Ind Pharm, 2020 Feb;46(2):264-271.
    PMID: 32000536 DOI: 10.1080/03639045.2020.1716377
    Topical drug delivery for local anesthetics has been an interesting area of research for formulators considering the resistance and barrier properties of skin and high clearance rate of drugs like prilocaine and lidocaine (duration of action < 2.5 h). In this study, efforts have been made to sustain the release of prilocaine and lidocaine by using depot microemulsion system. Drug loaded microemulsions were formulated using Capmul MCM, Pluronic F127, polyethylene glycol 200 (PEG 200) and water from pseudo-ternary diagrams. The Smix at 1:4 ratio showed larger microemulsion area in comparison to 1:2 ratio. The ex-vivo studies indicate sustained release of prilocaine and lidocaine from the microemulsion up to 8 h, in comparison to 4 h with ointments. Skin irritation study on rabbits confirmed the safety of drug loaded microemulsions for local drug delivery. The improved ex vivo data is reflected in the in vivo studies, were radiant heat tail-flick test and sciatic nerve model showed prolong duration of action for both prilocaine and lidocaine microemulsions in comparison to ointment. The in vitro and in vivo efficacy of prilocaine and lidocaine was non-significant. The improved efficacy was due to high penetration of microemulsion and depot effect due to local precipitation (destabilization of microemulsion) of drug in the skin layer. The sustained local anesthetic effect is highly desirable for the treatment of skin irritation due to skin burns and pre- and post-operative pain.
  4. Fulltext Optimizing strength of directly recycled aluminum chip-based parts through a hybrid RSM-GA-ANN approach in sustainable hot forging
    Altharan YM, Shamsudin S, Lajis MA, Al-Alimi S, Yusuf NK, Alduais NAM, et al.
    PLoS One, 2024;19(3):e0300504.
    PMID: 38484005 DOI: 10.1371/journal.pone.0300504
    Direct recycling of aluminum waste is crucial in sustainable manufacturing to mitigate environmental impact and conserve resources. This work was carried out to study the application of hot press forging (HPF) in recycling AA6061 aluminum chip waste, aiming to optimize operating factors using Response Surface Methodology (RSM), Artificial Neural Network (ANN) and Genetic algorithm (GA) strategy to maximize the strength of recycled parts. The experimental runs were designed using Full factorial and RSM via Minitab 21 software. RSM-ANN models were employed to examine the effect of factors and their interactions on response and to predict output, while GA-RSM and GA-ANN were used for optimization. The chips of different morphology were cold compressed into billet form and then hot forged. The effect of varying forging temperature (Tp, 450-550°C), holding time (HT, 60-120 minutes), and chip surface area to volume ratio (AS:V, 15.4-52.6 mm2/mm3) on ultimate tensile strength (UTS) was examined. Maximum UTS (237.4 MPa) was achieved at 550°C, 120 minutes and 15.4 mm2/mm3 of chip's AS: V. The Tp had the largest contributing effect ratio on the UTS, followed by HT and AS:V according to ANOVA analysis. The proposed optimization process suggested 550°C, 60 minutes, and 15.4 mm2 as the optimal condition yielding the maximum UTS. The developed models' evaluation results showed that ANN (with MSE = 1.48%) outperformed RSM model. Overall, the study promotes sustainable production by demonstrating the potential of integrating RSM and ML to optimize complex manufacturing processes and improve product quality.
  5. Fulltext Characterization of a novel orthoreovirus isolated from fruit bat, China
    Hu T, Qiu W, He B, Zhang Y, Yu J, Liang X, et al.
    BMC Microbiol, 2014;14:293.
    PMID: 25433675 DOI: 10.1186/s12866-014-0293-4
    In recent years novel human respiratory disease agents have been described for Southeast Asia and Australia. The causative pathogens were classified as pteropine orthoreoviruses with a strong phylogenetic relationship to orthoreoviruses of bat origin.
  6. Fulltext Identification of a novel Getah virus by Virus-Discovery-cDNA random amplified polymorphic DNA (RAPD)
    Hu T, Zheng Y, Zhang Y, Li G, Qiu W, Yu J, et al.
    BMC Microbiol, 2012;12:305.
    PMID: 23268691 DOI: 10.1186/1471-2180-12-305
    The identification of new virus strains is important for the study of infectious disease, but current (or existing) molecular biology methods are limited since the target sequence must be known to design genome-specific PCR primers. Thus, we developed a new method for the discovery of unknown viruses based on the cDNA--random amplified polymorphic DNA (cDNA-RAPD) technique. Getah virus, belonging to the family Togaviridae in the genus Alphavirus, is a mosquito-borne enveloped RNA virus that was identified using the Virus-Discovery-cDNA RAPD (VIDISCR) method.
  7. Characterisation of calamansi (Citrus microcarpa). Part II: volatiles, physicochemical properties and non-volatiles in the juice
    Cheong MW, Zhu D, Sng J, Liu SQ, Zhou W, Curran P, et al.
    Food Chem, 2012 Sep 15;134(2):696-703.
    PMID: 23107680 DOI: 10.1016/j.foodchem.2012.02.139
    Calamansi juices from three countries (Malaysia, the Philippines and Vietnam) were characterised through measuring volatiles, physicochemical properties and non-volatiles (sugars, organic acids and phenolic acids). The volatile components of manually squeezed calamansi juices were extracted using dichloromethane and headspace solid-phase microextraction, and then analysed using gas chromatography-mass spectrometry/flame ionisation detector, respectively. A total of 60 volatile compounds were identified. The results indicated that the Vietnam calamansi juice contained the highest amount of volatiles. Two principal components obtained from principal component analysis (PCA) represented 89.65% of the cumulative total variations of the volatiles. Among the non-volatile components, these three calamansi juices could be, to some extent, differentiated according to fructose and glucose concentrations. Hence, this study of calamansi juices could lead to a better understanding of calamansi fruits.
  8. Fulltext Rapid Targeted Next-Generation Sequencing Platform for Molecular Screening and Clinical Genotyping in Subjects with Hemoglobinopathies
    Shang X, Peng Z, Ye Y, Asan, Zhang X, Chen Y, et al.
    EBioMedicine, 2017 Sep;23:150-159.
    PMID: 28865746 DOI: 10.1016/j.ebiom.2017.08.015
    Hemoglobinopathies are among the most common autosomal-recessive disorders worldwide. A comprehensive next-generation sequencing (NGS) test would greatly facilitate screening and diagnosis of these disorders. An NGS panel targeting the coding regions of hemoglobin genes and four modifier genes was designed. We validated the assay by using 2522 subjects affected with hemoglobinopathies and applied it to carrier testing in a cohort of 10,111 couples who were also screened through traditional methods. In the clinical genotyping analysis of 1182 β-thalassemia subjects, we identified a group of additional variants that can be used for accurate diagnosis. In the molecular screening analysis of the 10,111 couples, we detected 4180 individuals in total who carried 4840 mutant alleles, and identified 186 couples at risk of having affected offspring. 12.1% of the pathogenic or likely pathogenic variants identified by our NGS assay, which were undetectable by traditional methods. Compared with the traditional methods, our assay identified an additional at-risk 35 couples. We describe a comprehensive NGS-based test that offers advantages over the traditional screening/molecular testing methods. To our knowledge, this is among the first large-scale population study to systematically evaluate the application of an NGS technique in carrier screening and molecular diagnosis of hemoglobinopathies.
  9. Fulltext Undergraduate Students' Profiles of Cognitive Load in Augmented Reality-Assisted Science Learning and Their Relation to Science Learning Self-efficacy and Behavior Patterns
    Lin XF, Wong SY, Zhou W, Shen W, Li W, Tsai CC
    Int J Sci Math Educ, 2023 May 04.
    PMID: 37363784 DOI: 10.1007/s10763-023-10376-9
    Research evidence indicated that a specific type of augmented reality-assisted (AR-assisted) science learning design or support might not suit or be effective for all students because students' cognitive load might differ according to their experiences and individual characteristics. Thus, this study aimed to identify undergraduate students' profiles of cognitive load in AR-assisted science learning and to examine the role of their distinct profiles in self-efficacy together with associated behavior patterns in science learning. After ensuring the validity and reliability of each measure, a latent profile analysis confirmed that 365 Chinese undergraduates carried diverse dimensions of cognitive load simultaneously. The latent profile analysis findings revealed four fundamental profiles: Low Engagement, Immersive, Dabbling, and Organized, characterized as carrying various respective cognitive loads. The multivariate analysis of variance findings revealed different levels of the six AR science learning self-efficacy dimensions across profiles. Low Engagement students displayed the lowest self-efficacy among all dimensions. Organized students recorded better conceptual understanding and higher-order cognitive skills than Dabbling ones. Students with the Immersive profile had the highest science learning self-efficacy. The lag sequential analysis results showed significant differences in behavior patterns among profiles. Among them, profiles with social interaction, test, and reviewing feedback behavior had a significantly higher score for self-efficacy than those patterns mainly based on test learning and resource visits. This finding provides a unified consideration of students' diverse profiles and can inform interventions for effective design of AR-assisted science learning to match appropriate strategies to facilitate the science learning effect.
  10. Cultural adaptations and methodological innovations to group model building for the systems actions to reduce malnutrition in all its forms in Southeast Asian countries and China (SYSTAM CHINA-SEACS International Consortium) project
    Li B, He Z, Peters R, Allender S, Zou Y, Zhou W, et al.
    Int J Behav Nutr Phys Act, 2023 Sep 18;20(1):111.
    PMID: 37723534 DOI: 10.1186/s12966-023-01510-5
    BACKGROUND: Group Model Building (GMB) is a participatory system dynamics method increasingly used to address complex public health issues like obesity. GMB represents a set of well-defined steps to engage key stakeholders to identify shared drivers and solutions of a given problem. However, GMB has not yet been applied specifically to develop multi-duty interventions that address multiple inter-related issues such as malnutrition in all its forms (MIAIF). Moreover, a recent systematic review of empirical applications of a systems approach to developing obesity interventions found no published work from non-western, low- and middle-income countries (LMICs). In this paper we describe adaptations and innovations to a common GMB process to co-develop systemic MIAIF interventions with Chinese decision-makers.

    METHODS: We developed, piloted and implemented multiple cultural adaptations and two methodological innovations to the commonly used GMB process in Fang Cheng Gang city, China. We included formal, ceremonial and policy maker engagement events before and between GMB workshops, and incorporated culturally tailored arrangements during participant recruitment (officials of the same seniority level joined the same workshop) and workshop activities (e.g., use of individual scoring activities and hand boards). We made changes to the commonly used GMB activities which enabled mapping of shared drivers of multiple health issues (in our case MIAIF) in a single causal loop diagram. We developed and used a 'hybrid' GMB format combining online and in person facilitation to reduce travel and associated climate impact.

    RESULTS: Our innovative GMB process led to high engagement and support from decision-makers representing diverse governmental departments across the whole food systems. We co-identified and prioritised systemic drivers and intervention themes of MIAIF. The city government established an official Local Action Group for long-term, inter-departmental implementation, monitoring and evaluation of the co-developed interventions. The 'hybrid' GMB format enabled great interactions while reducing international travel and mitigating limitations of fully online GMB process.

    CONCLUSIONS: Cultural and methodological adaptations to the common GMB process for an Asian LMIC setting were successful. The 'hybrid' GMB format is feasible, cost-effective, and more environmentally friendly. These cultural adaptations could be considered for other Asian settings and beyond to address inter-related, complex issues such as MIAIF.

  11. A highly sensitive perovskite oxide sensor for detection of p-phenylenediamine in hair dyes
    He J, Sunarso J, Miao J, Sun H, Dai J, Zhang C, et al.
    J Hazard Mater, 2019 05 05;369:699-706.
    PMID: 30831522 DOI: 10.1016/j.jhazmat.2019.02.070
    Effective regulation of p-phenylenediamine (PPD), a widely used precursor of hair dye that is harmful to human health in large concentration, relies upon an accurate yet simple detection of PPD. In this context, amperometric electrode sensor based on perovskite oxide becomes attractive given its portability, low cost, high sensitivity, and rapid processing time. This work reports the systematic characterization of a series of Sr-doped PrCoO3-δ perovskite oxides with composition of Pr1-xSrxCoO3-δ(x = 0, 0.2, 0.4, 0.6, 0.8, and 1) for PPD detection in an alkaline solution. PSC82 deposited onto glassy carbon electrode (PSC82/GCE) generates the highest redox currents which correlates with the highest hydrogen peroxide intermediates (HO2-) yield and the σ*-orbital (eg) filling of Co that is closest to unity for PSC82. PSC82/GCE provides the highest sensitivities of 655 and 308 μA mM-1 cm-2 in PPD concentration range of 0.5-2,900 and 2,900-10,400 μM, respectively, with a limit of detection of 0.17 μM. PSC82/GCE additionally demonstrates high selectivity to PPD and long term stability during 50 consecutive cyclic voltammetry scans and over 1-month storage period. The potential applicability of PSC82/GCE was also demonstrated by confirming the presence of very low concentration of PPD of below 0.5% in real hair dyes.
  12. A Direct n-Butane Solid Oxide Fuel Cell Using Ba(Zr0.1Ce0.7Y0.1Yb0.1)0.9Ni0.05Ru0.05O3-δ Perovskite as the Reforming Layer
    Wang D, Wong SI, Sunarso J, Xu M, Wang W, Ran R, et al.
    ACS Appl Mater Interfaces, 2021 May 05;13(17):20105-20113.
    PMID: 33886260 DOI: 10.1021/acsami.1c02502
    Hydrocarbon-fueled solid oxide fuel cells (SOFCs) that can operate in the intermediate temperature range of 500-700 °C represent an attractive SOFC device for combined heat and power applications in the industrial market. One of the ways to realize such a device relies upon exploiting an in situ steam reforming process in the anode catalyzed by an anti-carbon coking catalyst. Here, we report a new Ni and Ru bimetal-doped perovskite catalyst, Ba(Zr0.1Ce0.7Y0.1Yb0.1)0.9Ni0.05Ru0.05O3-δ (BZCYYbNRu), with enhanced catalytic hydrogen production activity on n-butane (C4H10), which can resist carbon coking over extended operation durations. Ru in the perovskite lattice inhibits Ni precipitation from perovskite, and the high water adsorption capacity of proton conducting perovskite improves the coking resistance of BZCYYbNRu. When BZCYYbNRu is used as a steam reforming catalyst layer on a Ni-YSZ-supported anode, the single fuel cell not only achieves a higher power density of 1113 mW cm-2 at 700 °C under a 10 mL min-1 C4H10 continuous feed stream at a steam to carbon (H2O/C) ratio of 0.5 but also shows a much better operational stability for 100 h at 600 °C compared with those reported in the literature.
  13. Molybdenum and Niobium Codoped B-Site-Ordered Double Perovskite Catalyst for Efficient Oxygen Evolution Reaction
    Sun H, Chen G, Sunarso J, Dai J, Zhou W, Shao Z
    ACS Appl Mater Interfaces, 2018 May 23;10(20):16939-16942.
    PMID: 29741862 DOI: 10.1021/acsami.8b03702
    An abundant, highly active, and durable oxygen evolution reaction (OER) electrocatalyst is an enabling component for a more sustainable energy future. We report, herein, a molybdenum and niobium codoped B-site-ordered double perovskite oxide with a compositional formula of Ba2CoMo0.5Nb0.5O6-δ (BCMN) as an active and robust catalyst for OER in an alkaline electrolyte. BCMN displayed a low overpotential of 445 mA at a current density of 10 mA cm-2disk. BCMN also showed long-term stability in an alkaline medium. This work hints toward the possibility of combining a codoping approach with double perovskite structure formation to achieve significant enhancement in the OER performance.
  14. Systematic Study of Oxygen Evolution Activity and Stability on La1- xSr xFeO3-δ Perovskite Electrocatalysts in Alkaline Media
    She S, Yu J, Tang W, Zhu Y, Chen Y, Sunarso J, et al.
    ACS Appl Mater Interfaces, 2018 Apr 11;10(14):11715-11721.
    PMID: 29546981 DOI: 10.1021/acsami.8b00682
    Perovskite oxide is an attractive low-cost alternative catalyst for oxygen evolution reaction (OER) relative to the precious metal oxide-based electrocatalysts (IrO2 and RuO2). In this work, a series of Sr-doped La-based perovskite oxide catalysts with compositions of La1- xSr xFeO3-δ ( x = 0, 0.2, 0.5, 0.8, and 1) are synthesized and characterized. The OER-specific activities in alkaline solution increase in the order of LaFeO3-δ (LF), La0.8Sr0.2FeO3-δ (LSF-0.2), La0.5Sr0.5FeO3-δ (LSF-0.5), SrFeO3-δ (SF), and La0.2Sr0.8FeO3-δ (LSF-0.8). We establish a direct correlation between the enhancement in the specific activity and the amount of surface oxygen vacancies as well as the surface Fe oxidation states. The improved specific activity for LSF-0.8 is clearly linked to the optimum amount of surface oxygen vacancies and surface Fe oxidation states. We also find that the OER performance stability is a function of the crystal structure and the deviation in the surface La and/or Sr composition(s) from their bulk stoichiometric compositions. The cubic structure and lower deviation, as is the case for LSF-0.8, led to a higher OER performance stability. These surface performance relations provide a promising guideline for constructing efficient water oxidation.
  15. Fulltext Two orders of magnitude enhancement in oxygen evolution reactivity on amorphous Ba0.5Sr0.5Co0.8Fe0.2O3-δ nanofilms with tunable oxidation state
    Chen G, Zhou W, Guan D, Sunarso J, Zhu Y, Hu X, et al.
    Sci Adv, 2017 06;3(6):e1603206.
    PMID: 28691090 DOI: 10.1126/sciadv.1603206
    Perovskite oxides exhibit potential for use as electrocatalysts in the oxygen evolution reaction (OER). However, their low specific surface area is the main obstacle to realizing a high mass-specific activity that is required to be competitive against the state-of-the-art precious metal-based catalysts. We report the enhanced performance of Ba0.5Sr0.5Co0.8Fe0.2O3-δ (BSCF) for the OER with intrinsic activity that is significantly higher than that of the benchmark IrO2, and this result was achieved via fabrication of an amorphous BSCF nanofilm on a surface-oxidized nickel substrate by magnetron sputtering. The surface nickel oxide layer of the Ni substrate and the thickness of the BSCF film were further used to tune the intrinsic OER activity and stability of the BSCF catalyst by optimizing the electronic configuration of the transition metal cations in BSCF via the interaction between the nanofilm and the surface nickel oxide, which enables up to 315-fold enhanced mass-specific activity compared to the crystalline BSCF bulk phase. Moreover, the amorphous BSCF-Ni foam anode coupled with the Pt-Ni foam cathode demonstrated an attractive small overpotential of 0.34 V at 10 mA cm-2 for water electrolysis, with a BSCF loading as low as 154.8 μg cm-2.
  16. New Phosphorus-Doped Perovskite Oxide as an Oxygen Reduction Reaction Electrocatalyst in an Alkaline Solution
    Shen Y, Zhu Y, Sunarso J, Guan D, Liu B, Liu H, et al.
    Chemistry, 2018 May 11;24(27):6950-6957.
    PMID: 29411451 DOI: 10.1002/chem.201705675
    Because of their structural and compositional flexibility, perovskite oxides represent an attractive alternative electrocatalyst class to precious metals for the oxygen reduction reaction (ORR); an important reaction in fuel cells and metal-air batteries. Partial replacement of the original metal cation with another cation, namely, doping, can be used to tailor the ORR activity of perovskite, for which a metal has been exclusively used as the dopant component in the past. Herein, phosphorus is proposed as a non-metal dopant for the cation site to develop a new perovskite family with the formula of La0.8 Sr0.2 Mn1-x Px O3-δ (x=0, 0.02, 0.05, and 0.1; denoted as LSM, LSMP0.02, LSMP0.05, and LSMP0.1, respectively). Powder XRD patterns reveal that the solubility of phosphorus in the perovskite structure is around 0.05. Rotating ring-disk electrode experiments in the form of linear-sweep voltammetry scans demonstrated the best ORR performance for LSMP0.05, and also revealed close to a four-electron ORR pathway for all four compositions. A chronoamperometric test (9000 s) and 500 cycle accelerated durability test demonstrated higher durability for LSMP0.05 relative to that of LSM and the commercial 20 wt % Pt/C catalyst. The higher ORR activity for LSMP0.05 is attributed to the optimised average valence of Mn, as evidenced by combined X-ray photoelectron spectroscopy and soft X-ray absorption spectroscopy data. Doping phosphorus into perovskites is an effective way to develop high-performance electrocatalysts for ORR.
  17. Nanostructured Co-Mn containing perovskites for degradation of pollutants: Insight into the activity and stability
    Miao J, Sunarso J, Duan X, Zhou W, Wang S, Shao Z
    J Hazard Mater, 2018 May 05;349:177-185.
    PMID: 29425884 DOI: 10.1016/j.jhazmat.2018.01.054
    The efficient oxidative removal of persistent organic components in wastewater relies on low-cost heterogeneous catalysts that offer high catalytic activity, stability, and recyclability. Here, we designed a series of nanostructured Co-Mn containing perovskite catalysts, LaCo1-xMnxO3+δ (LCM, x = 0, 0.3, 0.5, 0.7, and 1.0), with over-stoichiometric oxygen (δ > 0) to show superior catalytic activity for the degradation of a variety of persistent aqueous organic pollutants by activating peroxymonosulfate (PMS). The nature of LCM for catalysis was comprehensively investigated. A "volcano-shaped" correlation was observed between the catalytic activity and electron filling (eg) of Co in LCM. Among these compounds, LaCo0.5Mn0.5O3+δ (LCM55) exhibited an excellent activity with eg = 1.27. The high interstitial oxygen ion diffusion rate (DO2- = 1.58 ± 0.01 × 10-13 cm2 s-1) of LCM55 also contributes to its catalytic activity. The enhanced stability of LCM55 can be ascribed to its stronger relative acidity (3.22). Moreover, an increased solution pH (pH ≥ 7) generated a faster organic degradation rate and a decrease in metal leaching (0.004 mM) for LCM55 perovskite, justifying it as a potential material for environmental remediation.
  18. Fulltext SrCo1-xTixO3-δ perovskites as excellent catalysts for fast degradation of water contaminants in neutral and alkaline solutions
    Miao J, Sunarso J, Su C, Zhou W, Wang S, Shao Z
    Sci Rep, 2017 03 10;7:44215.
    PMID: 28281656 DOI: 10.1038/srep44215
    Perovskite-like oxides SrCo1-xTixO3-δ (SCTx, x = 0.1, 0.2, 0.4, 0.6) were used as heterogeneous catalysts to activate peroxymonosulfate (PMS) for phenol degradation under a wide pH range, exhibiting more rapid phenol oxidation than Co3O4 and TiO2. The SCT0.4/PMS system produced a high activity at increased initial pH, achieving optimized performance at pH ≥ 7 in terms of total organic carbon removal, the minimum Co leaching and good catalytic stability. Kinetic studies showed that the phenol oxidation kinetics on SCT0.4/PMS system followed the pseudo-zero order kinetics and the rate on SCT0.4/PMS system decreased with increasing initial phenol concentration, decreased PMS amount, catalyst loading and solution temperature. Quenching tests using ethanol and tert-butyl alcohol demonstrated sulfate and hydroxyl radicals for phenol oxidation. This investigation suggested promising heterogeneous catalysts for organic oxidation with PMS, showing a breakthrough in the barriers of metal leaching, acidic pH, and low efficiency of heterogeneous catalysis.
  19. Fulltext Bifunctionality from Synergy: CoP Nanoparticles Embedded in Amorphous CoOx Nanoplates with Heterostructures for Highly Efficient Water Electrolysis
    Yu J, Zhong Y, Wu X, Sunarso J, Ni M, Zhou W, et al.
    Adv Sci (Weinh), 2018 Sep;5(9):1800514.
    PMID: 30250794 DOI: 10.1002/advs.201800514
    Hydrogen production from renewable electricity relies upon the development of an efficient alkaline water electrolysis device and, ultimately, upon the availability of low cost and stable electrocatalysts that can promote oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). Normally, different electrocatalysts are applied for HER and OER because of their different reaction intermediates and mechanisms. Here, the synthesis of a heterostructured CoP@a-CoOx plate, which constitutes the embedded crystalline cobalt phosphide (CoP) nanoclusters and amorphous cobalt oxides (CoOx) nanoplates matrix, via a combined solvothermal and low temperature phosphidation route is reported. Due to the presence of synergistic effect between CoP nanoclusters and amorphous CoOx nanoplates in the catalyst, created from the strong nanointerfaces electronic interactions between CoP and CoOx phases in its heterostructure, this composite displays very high OER activity in addition to favorable HER activity that is comparable to the performance of the IrO2 OER benchmark and approached that of the Pt/C HER benchmark. More importantly, an efficient and stable alkaline water electrolysis operation is achieved using CoP@a-CoOx plate as both cathode and anode as evidenced by the obtainment of a relatively low potential of 1.660 V at a 10 mA cm-2 current density and its marginal increase above 1.660 V over 30 h continuous operation.
  20. Fulltext To use or not to use: an update on licit and illicit ketamine use
    Li JH, Vicknasingam B, Cheung YW, Zhou W, Nurhidayat AW, Jarlais DC, et al.
    Subst Abuse Rehabil, 2011;2:11-20.
    PMID: 24474851 DOI: 10.2147/SAR.S15458
    Ketamine, a derivative of phencyclidine that was developed in the 1960s, is an anesthetic and analgesic with hallucinogenic effects. In this paper, the pharmacological and toxicological effects of ketamine are briefly reviewed. Ketamine possesses a wide safety margin but such a therapeutic benefit is somewhat offset by its emergence phenomenon (mind-body dissociation and delirium) and hallucinogenic effects. The increasing abuse of ketamine, initially predominantly in recreational scenes to experience a "k-hole" and other hallucinatory effects but more recently also as a drug abused during the workday or at home, has further pushed governments to confine its usage in many countries. Recently, urinary tract dysfunction has been associated with long-term ketamine use. In some long-term ketamine users, such damage can be irreversible and could result in renal failure and dialysis. Although ketamine has not yet been scheduled in the United Nations Conventions, previous studies using different assessment parameters to score the overall harms of drugs indicated that ketamine may cause more harm than some of the United Nations scheduled drugs. Some countries in Southeast and East Asia have reported an escalating situation of ketamine abuse. Dependence, lower urinary tract dysfunction, and sexual impulse or violence were the most notable among the ketamine-associated symptoms in these countries. These results implied that the danger of ketamine may have been underestimated previously. Therefore, the severity levels of the ketamine-associated problems should be scrutinized more carefully and objectively. To prevent ketamine from being improperly used and evolving into an epidemic, a thorough survey on the prevalence and characteristics of illicit ketamine use is imperative so that suitable policy and measures can be taken. On the other hand, recent findings that ketamine could be useful for treating major depressive disorder has given this old drug a new impetus. If ketamine is indeed a remedy for treating depression, more research on the risks and benefits of its clinical use will be indispensable.
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