35 research outputs found

    Heavy metals leaching behaviour assessment of palm oil clinker

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    Technical benefit of incorporation of Palm Oil Clinker (POC) in cement-based applications has been proven in recent studies. The aim of this work was to assess the heavy metal leaching behavior to ensure environmental safety of using POC in cement-based applications. The chemical composition, morphology, total organic carbon (TOC) and mineralogy were determined using XRF, FESEM, TOC analyzers and XRD to select appropriate chemical reagents for complete digestion. HNO3, HF and HClO4 were used for digestion of POC to measure heavy metal content using ICP-MS. The chemical reagents CH3COOH, NH2OH-HCl, H2O2+CH3COONH4 and HF+HNO3+HCl were used for extraction of acid soluble, reducible, oxidizable and residual fractions of heavy metals in POC, respectively. The leaching toxicity of the POC was investigated by the USEPA 1311 TCLP method. The result showed the presence of Be, V, Cr, Ni, Cu, Zn, As, Se, Ag, Cd, Ba and Pb with levels of 5.13, 11.02, 2.65, 1.93, 45.43, 11.84, 15.07, 0, 0, 81.97 and 1.76 mg/kg, respectively, in POC. The leaching value in mg/L of As (4.56), Cu(1.05), Be (0.89), Zn(0.51), Ba(0.26), Ni (0.17), V(0.15), Cr(0.001) and Se (0.001) is found well below the standard limit of risk. Risk assessment code (RAC) analysis confirms the safe incorporation of POC in cement-based applications

    Volumetric Properties of Binary Mixtures of 2-Ethoxyethanol and 2-Butoxyethanol with 1,4-Dioxane

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    Densities, r, of 2-Ethoxyethanol (EGMEE) + 1,4-Dioxane (DXN) and  2-Butoxyethanol (EGMBE) + 1,4-Dioxane (DXN) systems have been measured in the whole range of composition at an interval of 5 K ranging from 303.15 to 323.15 K. Excess molar volumes, , partial molar volumes, , thermal expansivities,a, and excess thermal expansivities, aE, have been estimated from the experimental values of ρ. All of the derived properties have been fitted to appropriate polynomials. Values of   and aE were fitted to the Redlich-Kister polynomial equation and their variations with composition and temperature have been discussed in terms of molecular interaction in the mixtures. Values of  and aE were all positive and were attributed due to specific interactions

    Impact of tetrabutylammonium, iodide and triiodide ions conductivity in polyacrylonitrile based electrolyte on DSSC performance

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    Gel polymer electrolytes (GPEs) with polyacrylonitrile (PAN)-based polymer, ethylene carbonate (EC) and propylene carbonate (PC) plasticizers, and different amounts of tetrabutylammonium iodide (TBAI) salt and iodine (I2) have been prepared and used in dye-sensitized solar cells (DSSCs). The maximum room temperature conductivity of 5.14 mS cm−1 is obtained for electrolyte with a composition of 8 wt% PAN-30 wt% EC-30 wt% PC-30 wt% TBAI-2 wt% I2 (S3 electrolyte) which influenced by the highest charge carrier density of 7.93 × 1020 cm−3 estimated from fitting the impedance Nyquist plot. The DSSC fabricated with S3 electrolyte revealed the highest power conversion efficiency of 3.45% with open-circuit voltage (Voc) of 582 mV and short-circuit current density (Jsc) of 12.9 mA cm−2. The incident photon-to-current conversion efficiency of the DSSC with highest efficiency is 54.01%. The electrical impedance spectroscopy of the same cell shows the lowest series resistance indicating the superiority of electrolyte charge transport characteristics in DSSC. In addition, electron transfer time constant and electron recombination time , charge collection efficiency , electron diffusion coefficient and diffusion length of DSSC fabricated with GPEs prepared have been estimated by intensity-modulated photocurrent spectroscopy and intensity-modulated photovoltage spectroscopy techniques. The DSSC with highest efficiency shows lowest of 34.46 ms and highest of 90.41 ms due to the huge amount of TBA+ ions that covered the surface area of mesoporous TiO2. The of 0.62, D of 4.00 × 10−5 cm2 s−1 and of 19.02 μm further support the photovoltaic efficiency of DSSC

    Toward polymer composites based and architectural engineering induced flexible electrodes for lithium-ion batteries

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    Recently, polymers, especially conducting (CPs) and non-conducting polymers (nCPs), have been emerged as the promising flexible electrode components for lithium-ion batteries due to their inherent high mechanical tolerance limit, excellent thermal and chemical stability, low density, ease of processing, low cost, and versatility. In addition, CPs provide good electrical conductivity. Polymeric structures remain almost the same even after hundreds to thousands of electrochemical cycles. However, some crucial factors, such as low conductivity, energy density, and rate performance, often limit the large-scale exploitation of these polymers. Although CPs, and nCPs can provide the desired flexibility, nCPs, in particular, increase the ‘dead volume’ of electrodes. In this context, it is necessary to resolve the issues existing with the polymers to make them effective confinement matrices for flexible electrodes. On the other hand, customizing the electrode architectures is vital for achieving multidirectional flexibility without compromising energy density and overall capacity. However, low active materials loading and deviation from the customized structures after several deformation cycles still affect the desired performance in terms of electrochemical and mechanical. Furthermore, the intricate and costly preparation processes of customized electrodes are the major bottlenecks toward practical applications. This review discusses the recent progress, merits, and demerits of the most widely studied polymer composites-based and architectural engineering induced flexible electrodes for lithium-ion batteries (LIBs). Both CPs and nCPs are discussed in the perspectives of current research status, major limitations, key factors associated with electrochemical performances and future outlook of the developments on polymer-based flexible electrodes

    An Actuarial Analysis of Calibration of Crop Insurance Premiums to Heterogeneous Risks

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    This paper examines whether the loadings on the crop insurance premium rates for risks such as moral hazard and adverse selection are adequate. From the discrete choice (tobit) analysis conducted, we discover that the premium loadings for 75% coverage level are not adequate, resulting in losses for the Risk Management Agency

    Electrocatalytic and structural properties and computational calculation of PAN-EC-PC-TPAI-I2 gel polymer electrolytes for dye sensitized solar cell application

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    In this study, gel polymer electrolytes (GPEs) were prepared using polyacrylonitrile (PAN) polymer, ethylene carbonate (EC), propylene carbonate (PC) plasticizers and different compositions of tetrapropylammonium iodide (TPAI) salt. Linear sweep voltammetry (LSV) and electrochemical impedance spectroscopy (EIS) measurements were done using non-blocking Pt-electrode symmetric cells. The limiting current (Jlim), apparent diffusion coefficient of triiodide ions ðD* I3 Þ and exchange current were found to be 12.76 mA cm2 , 23.41 107 cm2 s 1 and 11.22–14.24 mA cm2 , respectively, for the GPE containing 30% TPAI. These values are the highest among the GPEs with different TPAI contents. To determine the ionic conductivity, the EIS technique was employed with blocking electrodes. The GPE containing 30% TPAI exhibited the lowest bulk impedance, Rb (22 U), highest ionic conductivity (3.62 103 S cm1 ) and lowest activation energy. Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) techniques were utilized for structural characterization. Functional group interactions among PAN, EC, PC and TPAI were studied in the FTIR spectra of the GPEs. An up-shift of the XRD peak indicates the polymer–salt interaction and possible complexation of the cation (TPA+ ion) with the lone pair of electrons containing site –C^N at the N atom in the host polymer matrix. On the other hand, computational study shows that TPAI-PAN based GPE possesses the lowest frontier orbital bandgap, which coincided with the enhanced electrochemical and electrocatalytic performance of GPE. The dyesensitized solar cell (DSSC) fabricated with these GPEs showed that the JSC (19.75 mA cm2 ) and VOC (553.8 mV) were the highest among the GPEs and hence the highest efficiency, h (4.76%), was obtained for the same electrolyte

    Assessment of NER solutions against the first and second CALBC Silver Standard Corpus

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    Background Competitions in text mining have been used to measure the performance of automatic text processing solutions against a manually annotated gold standard corpus (GSC). The preparation of the GSC is time-consuming and costly and the final corpus consists at the most of a few thousand documents annotated with a limited set of semantic groups. To overcome these shortcomings, the CALBC project partners (PPs) have produced a large-scale annotated biomedical corpus with four different semantic groups through the harmonisation of annotations from automatic text mining solutions, the first version of the Silver Standard Corpus (SSC-I). The four semantic groups are chemical entities and drugs (CHED), genes and proteins (PRGE), diseases and disorders (DISO) and species (SPE). This corpus has been used for the First CALBC Challenge asking the participants to annotate the corpus with their text processing solutions. Results All four PPs from the CALBC project and in addition, 12 challenge participants (CPs) contributed annotated data sets for an evaluation against the SSC-I. CPs could ignore the training data and deliver the annotations from their genuine annotation system, or could train a machine-learning approach on the provided pre-annotated data. In general, the performances of the annotation solutions were lower for entities from the categories CHED and PRGE in comparison to the identification of entities categorized as DISO and SPE. The best performance over all semantic groups were achieved from two annotation solutions that have been trained on the SSC-I. The data sets from participants were used to generate the harmonised Silver Standard Corpus II (SSC-II), if the participant did not make use of the annotated data set from the SSC-I for training purposes. The performances of the participants’ solutions were again measured against the SSC-II. The performances of the annotation solutions showed again better results for DISO and SPE in comparison to CHED and PRGE. Conclusions The SSC-I delivers a large set of annotations (1,121,705) for a large number of documents (100,000 Medline abstracts). The annotations cover four different semantic groups and are sufficiently homogeneous to be reproduced with a trained classifier leading to an average F-measure of 85%. Benchmarking the annotation solutions against the SSC-II leads to better performance for the CPs’ annotation solutions in comparison to the SSC-I

    The genetic architecture of the human cerebral cortex

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    The cerebral cortex underlies our complex cognitive capabilities, yet little is known about the specific genetic loci that influence human cortical structure. To identify genetic variants that affect cortical structure, we conducted a genome-wide association meta-analysis of brain magnetic resonance imaging data from 51,665 individuals. We analyzed the surface area and average thickness of the whole cortex and 34 regions with known functional specializations. We identified 199 significant loci and found significant enrichment for loci influencing total surface area within regulatory elements that are active during prenatal cortical development, supporting the radial unit hypothesis. Loci that affect regional surface area cluster near genes in Wnt signaling pathways, which influence progenitor expansion and areal identity. Variation in cortical structure is genetically correlated with cognitive function, Parkinson's disease, insomnia, depression, neuroticism, and attention deficit hyperactivity disorder

    Global, regional, and national burden of disorders affecting the nervous system, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021

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    BackgroundDisorders affecting the nervous system are diverse and include neurodevelopmental disorders, late-life neurodegeneration, and newly emergent conditions, such as cognitive impairment following COVID-19. Previous publications from the Global Burden of Disease, Injuries, and Risk Factor Study estimated the burden of 15 neurological conditions in 2015 and 2016, but these analyses did not include neurodevelopmental disorders, as defined by the International Classification of Diseases (ICD)-11, or a subset of cases of congenital, neonatal, and infectious conditions that cause neurological damage. Here, we estimate nervous system health loss caused by 37 unique conditions and their associated risk factors globally, regionally, and nationally from 1990 to 2021.MethodsWe estimated mortality, prevalence, years lived with disability (YLDs), years of life lost (YLLs), and disability-adjusted life-years (DALYs), with corresponding 95% uncertainty intervals (UIs), by age and sex in 204 countries and territories, from 1990 to 2021. We included morbidity and deaths due to neurological conditions, for which health loss is directly due to damage to the CNS or peripheral nervous system. We also isolated neurological health loss from conditions for which nervous system morbidity is a consequence, but not the primary feature, including a subset of congenital conditions (ie, chromosomal anomalies and congenital birth defects), neonatal conditions (ie, jaundice, preterm birth, and sepsis), infectious diseases (ie, COVID-19, cystic echinococcosis, malaria, syphilis, and Zika virus disease), and diabetic neuropathy. By conducting a sequela-level analysis of the health outcomes for these conditions, only cases where nervous system damage occurred were included, and YLDs were recalculated to isolate the non-fatal burden directly attributable to nervous system health loss. A comorbidity correction was used to calculate total prevalence of all conditions that affect the nervous system combined.FindingsGlobally, the 37 conditions affecting the nervous system were collectively ranked as the leading group cause of DALYs in 2021 (443 million, 95% UI 378–521), affecting 3·40 billion (3·20–3·62) individuals (43·1%, 40·5–45·9 of the global population); global DALY counts attributed to these conditions increased by 18·2% (8·7–26·7) between 1990 and 2021. Age-standardised rates of deaths per 100 000 people attributed to these conditions decreased from 1990 to 2021 by 33·6% (27·6–38·8), and age-standardised rates of DALYs attributed to these conditions decreased by 27·0% (21·5–32·4). Age-standardised prevalence was almost stable, with a change of 1·5% (0·7–2·4). The ten conditions with the highest age-standardised DALYs in 2021 were stroke, neonatal encephalopathy, migraine, Alzheimer's disease and other dementias, diabetic neuropathy, meningitis, epilepsy, neurological complications due to preterm birth, autism spectrum disorder, and nervous system cancer.InterpretationAs the leading cause of overall disease burden in the world, with increasing global DALY counts, effective prevention, treatment, and rehabilitation strategies for disorders affecting the nervous system are needed
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