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•Biodiesel is an effective way to overcome environmental issue by diesel fuel.•Two stage acid (H2SO4) and base (NaOH) catalyst transesterification process ware carried out to produce ...methyl ester.•Properties of produced jatropha, sterculia and ceiba methyl ester are within the ASTM D6751 standard.•The methyl ester content was 96.75%, 97.50% and 97.72% for JCME, SFME and CPME respectively.
Biodiesel production from non-edible vegetable oil is one of the effective ways to overcome the problems associated with energy crisis and environmental issues. The non-edible oils represent potential sources for future energy supply. In this study, the physical and chemical properties of crude Jatropha curcas oil (CJCO), crude Sterculia foetida oil (CSFO) and crude Ceiba pentandra oil (CCPO) and its methyl ester have been studied. The acid values of three oils were found to be 12.78mg KOH per g, 5.11mg KOH per g and 11.99mg KOH per g which required acid-esterification and alkali-transesterification process. Acid value was decreased by esterification process using sulfuric acid anhydrous (H2SO4) as a catalyst and alkaline (NaOH) catalyst transesterification was carried out for the conversion of crude oil to methyl esters. The optimal conditions of FAME yield achieved for those three biodiesel were 96.75%, 97.50% and 97.72% respectively. Furthermore, the fuel properties of J. curcas methyl ester (JCME), S. foetida methyl ester (SFME) and C. pentandra methyl ester (CPME) were determined and evaluated. As a result, those produced biodiesel matched and fulfilled ASTM 6751 and EN 14214 biodiesel standards. Based on the results, JCME, SFME and CPME are potential non-edible feedstock for biodiesel production.
No studies have investigated the influence of ethnicity in a multi-ethnic middle-income country with a long-standing history of co-habitation. Stool samples from 214 Malaysian community members (46 ...Malay, 65 Chinese, 49 Indian, and 54 Jakun) were collected. The gut microbiota of the participants was investigated using 16S amplicon sequencing. Ethnicity exhibited the largest effect size across participants (PERMANOVA Pseudo-F = 4.24, R
= 0.06, p = 0.001). Notably, the influence of ethnicity on the gut microbiota was retained even after controlling for all demographic, dietary factors and other covariates which were significantly associated with the gut microbiome (PERMANOVA Pseudo-F = 1.67, R
= 0.02, p = 0.002). Our result suggested that lifestyle, dietary, and uncharacterized differences collectively drive the gut microbiota variation across ethnicity, making ethnicity a reliable proxy for both identified and unidentified lifestyle and dietary variation across ethnic groups from the same community.
Biodiesel is biodegradable and nontoxic alternative fuel for diesel engine which has become more attractive to replace diesel fuel. In this study, vegetable oil was identified as potential sources ...for biodiesel production. The production of biodiesel from different non-edible oilseed crops has been extensively investigated for the past few years. Thus, the aim of this study is to critically review on the characteristic of the potential biodiesel and biodiesel diesel blends fuel properties. The aspects of this study cover the biodiesel production and fuel properties of biodiesel and biodiesel blends. Besides, some studies have shown that there is a direct correlation between fatty acid composition and biodiesel properties. The fuel properties of biodiesel blends fuel were very close to diesel fuels and satisfied ASTM 6751 and EN 14214 standards. As a final note, further study on the utilization of biodiesel blends needs to be carried out in order to ensure optimization in engine operation.
Emerging applications such as the Internet-of-Things and more-electric aircraft require electronics with integrated data storage that can operate in extreme temperatures with high energy efficiency. ...As transistor leakage current increases with temperature, nanoelectromechanical relays have emerged as a promising alternative. However, a reliable and scalable non-volatile relay that retains its state when powered off has not been demonstrated. Part of the challenge is electromechanical pull-in instability, causing the beam to snap in after traversing a section of the airgap. Here we demonstrate an electrostatically actuated nanoelectromechanical relay that eliminates electromechanical pull-in instability without restricting the dynamic range of motion. It has several advantages over conventional electrostatic relays, including low actuation voltages without extreme reduction in critical dimensions and near constant actuation airgap while the device moves, for improved electrostatic control. With this nanoelectromechanical relay we demonstrate the first high-temperature non-volatile relay operation, with over 40 non-volatile cycles at 200
C.
Denosumab treatment for fibrous dysplasia Boyce, Alison M; Chong, William H; Yao, Jack ...
Journal of bone and mineral research,
July 2012, Volume:
27, Issue:
7
Journal Article
Hybrid glasses connect the emerging field of metal-organic frameworks (MOFs) with the glass formation, amorphization and melting processes of these chemically versatile systems. Though inorganic ...zeolites collapse around the glass transition and melt at higher temperatures, the relationship between amorphization and melting has so far not been investigated. Here we show how heating MOFs of zeolitic topology first results in a low density 'perfect' glass, similar to those formed in ice, silicon and disaccharides. This order-order transition leads to a super-strong liquid of low fragility that dynamically controls collapse, before a subsequent order-disorder transition, which creates a more fragile high-density liquid. After crystallization to a dense phase, which can be remelted, subsequent quenching results in a bulk glass, virtually identical to the high-density phase. We provide evidence that the wide-ranging melting temperatures of zeolitic MOFs are related to their network topologies and opens up the possibility of 'melt-casting' MOF glasses.
The Global Resuscitation Alliance (GRA) was established in 2015 to improve survival for Out- of-Hospital Cardiac Arrest (OHCA) using the best practices developed by the Seattle Resuscitation Academy. ...However, these 10 programs were recommended in the context of developed Emergency Care Systems (ECS). Implementing these programs can be challenging for ECS at earlier stages of development. We aimed to explore barriers faced by developing ECS and to establish pre-requisites needed. We also developed a framework by which developing ECS may use to build their emergency response capability.
A consensus meeting was held in Singapore on 1st–2nd August 2017. The 74 participants were key stakeholders from 26 countries, including Emergency Medical Services (EMS) directors, physicians and academics, and two Physicians who sit on the World Health Organisation (WHO) panel for development of Emergency Care Systems. Five discussion groups examined the chain of survival: community, dispatch, ambulance and hospital; a separate group considered perinatal resuscitation. Discussion points were voted upon to reach a consensus.
The answers and discussion points from each groupwere classified into a table adapted from WHO’s framework of development for Emergency Services. After which, it was used to construct the modified survival framework with the chain of survival as the backbone. Eleven key statements were then derived to describe the pre-requisites for achieving the GRA 10 programs. The participants eventually voted on the importance and feasibility of these 11 statements as well as the GRA 10 programs using a matrix that is used by organisations to prioritise their action steps.
In this paper, we propose a modified framework of survival for developing ECS systems. There are barriers for developing ECS systems to improve OHCA survival rates. These barriers may be overcome by systematic prioritisation and cost-effective innovative solutions.
We report on multicolor excitation experiments with color centers in hexagonal boron nitride at cryogenic temperatures. We demonstrate controllable optical switching between bright and dark states of ...color centers emitting around 2 eV. Resonant, or quasi-resonant, excitation of photoluminescence also pumps the color center, via a two-photon process, into a dark state, where it becomes trapped. Repumping back into the bright state has a step-like spectrum with a defect-dependent threshold between 2.25 and 2.6 eV. This behavior is consistent with photoionization and charging between optically bright and dark states of the defect. Furthermore, a second zero phonon line, detuned by +0.4 eV, is observed in absorption with orthogonal polarization to the emission, evidencing an additional energy level in the color center.
A new alpha-emitting isotope U-214, produced by the fusion-evaporation reaction W-182(Ar-36,4n) U-214, was identified by employing the gas-filled recoil separator SHANS and the recoil-a correlation ...technique. More precise a-decay properties of even-even nuclei U-216,U-218 were also measured in the reactions of Ar-40, Ca-40 beams with W-180,W-182,W- 184 targets. By combining the experimental data, improved alpha-decay reduced widths delta(2) for the even-even Po-Pu nuclei in the vicinity of the magic neutron number N = 126 are deduced. Their systematic trends are discussed in terms of the N-p N-n scheme in order to study the influence of protonneutron interaction on a decay in this region of nuclei. It is strikingly found that the reduced widths of( 214,216)U are significantly enhanced by a factor of two as compared with the NpNn systematics for the 84 <= Z <= 90 and N < 126 even-even nuclei. The abnormal enhancement is interpreted by the strong monopole interaction between the valence protons and neutrons occupying the pi 1f (7/2) and nu 1f(5/2) spin-orbit partner orbits, which is supported by the large-scale shell model calculation.
Graphene has the potential to act as a high-performance reinforcement for adhesives or fibre composites when combined with epoxy polymer. However, it is currently mostly available not as single high ...aspect ratio sheets but as graphene nanoplatelets (GNPs), comprising stacks of graphene sheets. GNPs of a range of lateral size, thickness, aspect ratio and surface functionality were used to modify an anhydride-cured epoxy polymer. The morphology, mechanical properties and toughening mechanisms of these modified epoxies were investigated. The GNPs were sonicated in tetrahydrofuran (THF) or
n
-methyl-pyrrolidone (NMP) to facilitate dispersion in the epoxy. The use of THF resulted in large agglomerates, whereas more finely dispersed stacks of GNPs were observed for NMP. The maximum values of modulus (3.6 GPa at 1 wt%) and fracture energy (343 J/m
2
at 2 wt%) were measured for the epoxy modified with an intermediate platelet size of approximately 4
μ
m, compared to 2.9 GPa and 96 J/m
2
,
respectively, for the unmodified epoxy. The Young’s modulus was highly dependent on the dispersion quality, whereas the fracture energy was independent of the degree of GNP dispersion. The larger agglomerates of the GNPs which were dispersed in THF toughened the epoxy by crack deflection, whereas the GNPs dispersed in NMP showed platelet debonding, pull-out and plastic void growth of the epoxy. This work indicates that reinforcement and toughening can be achieved at much lower contents than for conventional modifiers. Further, achieving a good dispersion is crucial to the engineering application of these materials, and intermediate-sized graphene achieves the best balance of properties.
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