292 research outputs found

    Crystal structure of 4,4-dimethyl-2-(trifluoromethyl)-4,5-dihydro-1H-imidazole, C6H9F3N2

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    C6H9F3N2, monoclinic, P21/n (no. 14), a = 10.6224(9) Å, b = 11.8639(9) Å, c = 13.3139(11) Å, β = 105.903(3)°, V = 1613.6(2) Å3, Z = 8, Rgt(F) = 0.0618, wRref(F2) = 0.1629, T = 102(2) K [1–3]

    Non-linear buckling analysis of composite columns made from high and normal strength concrete under fire

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    Composite structures made from the combination of steel profile and concrete have significant loadbearing capacity which depends on the behaviour of the two material components and their interaction, particularly in fire conditions. It is not possible to assess the fire resistance of composite members only by considering the temperature of the steel, because the presence of the concrete may contribute greatly to increase the resistance, strength and thermal inertia of the member, which improves consequently the fire behaviour of the element. The aim of this work is to develop an efficient non-linear 3D finite element model to investigate the behaviour of pin-ended axially loaded composite column made from high strength concrete (HSC) and normal strength concrete (NSC) at different fire rating classes. Two types of column section were selected, notably HEB 160 profile totally encased with concrete and HEB220 partially encased with concrete. The fire behaviour of the columns was tested according to ISO834 standard fire. The results show that the use of HSC in composite columns reduces the level of fire protection with the regard to NSC. NSC in composite structures accommodates higher deflections than HSC, which is safer in case of fire accident. The mechanical resistance in composite columns at room temperature is reduced more than twice after 30 min of fire exposure.info:eu-repo/semantics/publishedVersio

    Isolation and characterization of phenol degrading bacterium strain Bacillus thuringiensis J20 from olive waste in Palestine

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    This study aimed at isolation of phenol degrading bacteria from olive mill wastes in Palestine. The efficiency of phenol removal and factors affecting phenol degradation were investigated. A bacterial strain (J20) was isolated from solid olive mill waste and identified as Bacillus thuringiensis based on standard morphological, biochemical characteristics and 16SrRNA sequence analysis. The strain was able to grow in a phenol concentration of 700 mg/L as the sole carbon and energy source. The culture conditions showed a significant impact on the ability of these cells to remove phenol. This strain exhibited optimum phenol degradation performance at pH 6.57 and 30 C . Under the optimized conditions, this strain could degrade 88.6% of phenol (700 mg/L) within 96 h when the initial cell density was OD600 0.2. However, the degradation efficiency could be improved from about 88% to nearly 99% by increasing the cell density. Immobilization of J20 was carried out using 4% sodium alginate. Phenol degradation efficiency of the immobilized cells of J20 was higher than that of the free cells, 100% versus 88.6% of 700 mg/L of phenol in 120 h, indicating the improved tolerance of the immobilized cells toward phenol toxicity. The J20 was used in detoxifying crude OMWW, phenolic compounds levels were reduced by 61% compared to untreated OMWW after five days of treatment. Hence, B. thuringiensis-J20 can be effectively used for bioremediation of phenol-contaminated sites in Palestine. These findings may lead to new biotechnological applications for the degradation of phenol, related to olive oil production.The authors thank Prof. Charles Greenblatt from Department of Microbiology and Molecular Genetics, Hebrew University – Hadassah Medical School, Jerusalem, Israel for his help. Suheir I. Ereqat and Ahmad A. Abdelkader contributed equally to this manuscript

    New Psychoactive Substances in the Homeless Population: A Cross-Sectional Study in the United Kingdom

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    The last few years have seen the emergence of new psychoactive substance among the homeless population, specifically synthetic cannabinoid receptor agonists. The purpose of this study is to investigate the knowledge and experiences of new psychoactive substances amongst users from the homeless population. An explanatory research design was applied using a semi-structured questionnaire with the focus on gaining insights on the prevalence, motivations and effects. Participants were recruited through convenience sampling from support organisations and charities UK-wide. Descriptive statistics and logistic regression were applied to analyse the data obtained from participant surveys. A total of 105 participants met the inclusion criteria and were in the age range of 18 to 64 years old. Almost 70% consumed new psychoactive substance products, which “Spice” was the most prevalent substance. Homeless users had consumed new psychoactive substance to escape reality and to self-treat themselves and stopped consumption due to the adverse effects. Adverse events were reported from the majority of the participants and led to more than 20% of the participants requiring medical treatment following hospitalisation. Findings from this study can contribute to the development of guidelines and policies that specifically address the needs of the homeless population who use new psychoactive substances

    New Psychoactive Substances in the Homeless Population: A Cross-Sectional Study in the United Kingdom

    Get PDF
    The last few years have seen the emergence of new psychoactive substance among the homeless population, specifically synthetic cannabinoid receptor agonists. The purpose of this study is to investigate the knowledge and experiences of new psychoactive substances amongst users from the homeless population. An explanatory research design was applied using a semi-structured questionnaire with the focus on gaining insights on the prevalence, motivations and effects. Participants were recruited through convenience sampling from support organisations and charities UK-wide. Descriptive statistics and logistic regression were applied to analyse the data obtained from participant surveys. A total of 105 participants met the inclusion criteria and were in the age range of 18 to 64 years old. Almost 70% consumed new psychoactive substance products, which “Spice” was the most prevalent substance. Homeless users had consumed new psychoactive substance to escape reality and to self-treat themselves and stopped consumption due to the adverse effects. Adverse events were reported from the majority of the participants and led to more than 20% of the participants requiring medical treatment following hospitalisation. Findings from this study can contribute to the development of guidelines and policies that specifically address the needs of the homeless population who use new psychoactive substances

    Cytotoxic activity of eurycoma longifolia jack root extract against nasopharyngeal carcinoma cell line

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    Background: Eurycoma longifolia (E. longifolia) or Tongkat Ali is a tree that grows in southeast Asia, the roots of which contain bioactive components that exhibit cytotoxic properties against various cancer cell lines. However, no study has been conducted to relate the cytotoxic properties against nasopharyngeal carcinoma (NPC), a type of cancer that shows poor prognosis for metastatic disease. The purpose of this study was to determine whether the E. longifolia root extract exerts cytotoxic activity against nasopharyngeal carcinoma (ORL-115) cell lines. Materials and Method: E. longifolia root extracts were obtained through Soxhlet extraction method and by using two different solvents; ethanol and dicholoromethane. MTS assay was used to evaluate the cytotoxic effect of the root extracts against ORL-115 cell line for three different incubation time which were 24-hour, 48-hour and 72-hour. Results: Ethanol extract was significantly more potent compared to DCM extract. Ethanol extract exhibited lower IC50 value compared to DCM extract. The IC50 of ethanol extract were 232.1 µg/ml, 66.86 µg/ml and 42.6 µg/ml. Meanwhile the IC50 of DCM extract were 678.87 µg/ml, 136.71 µg/ml, 73.72 µg/ml for 24-hour, 48-hour and 72-hour incubation period respectively. The cytotoxic activity of both extracts increased as the incubation time prolonged. The cytotoxic activity of ethanol extract at each incubation time was significantly different from DCM extract except at 72 hours. Conclusion: E. longifolia root extracts exerted cytotoxic activity against the nasopharyngeal carcinoma (ORL-115) cell line. Ethanol extract exhibited lower IC50 value compared to DCM extract. The cytotoxic activity of both extracts were dose dependent and time dependent

    Cobalt doped titania-carbon nanosheets with induced oxygen vacancies for photocatalytic degradation of uranium complexes in radioactive wastes

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    The photocatalytic degradation of uranium complexes is considered among the most efficient techniques for the efficient removal of uranium ions/complexes from radioactive wastewater. Described here is a nanostructured photocatalyst based on a cobalt-doped TiO2 composite with induced oxygen vacancies (Co@TiO2-C) for the photocatalytic removal of uranium complexes from contaminated water. The synergy between oxygen vacancies and Co-doping produced a material with a 1.7 eV bandgap, while the carbon network facilitates electron movement and hinders the e-h recombination. As a result, the new photocatalyst enables the decomposition of uranium-arsenazo iii complexes (U-ARZ3), followed by photocatalytic reduction of hexavalent uranium to insoluble tetravalent uranium. Combined with the nanosheet structure's high surface area, the photocatalytic decomposition, reduction efficiency, and kinetics were significantly enhanced, achieving almost complete U(vi) removal in less than 20 minutes from solution with a concentration as high as 1000 mL g−1. Moreover, the designed photocatalyst exhibits excellent stability and reusability without decreasing the photocatalytic performance after 5 cycles

    Public–Private Partnership in Tunisia: Enfidha Airport Assessment of an Infrastructure Achievement

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    One of the largest recent private-sector investments and the first airport private-sector concession in the Maghreb is Enfidha Airport, a key factor in the success of the Tunisian Government’s public– private partnership (PPP) strategy. However, since Tunisia’s Jasmine Revolution, political and social turmoil is sweeping the country and worsening the economic indicators. This article aims to assess this PPP infrastructure, allowing us to determine if it is profitable in the long term and contributes therefore to the economic growth. The case study reveals the key role of the economic, social, and political environment in Tunisia, the dawn of the Arab Spring
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