BET Size Research Articles

Production of low-cost adsorbent with small particle size from calcium carbonate rich residue carbonatation cake and their high performance phosphate adsorption applications

This study investigated phosphorus removal from aqueous solutions using carbonatisation cake, which is a sugar residue containing a significant amount of reactive calcium carbonate. The chemical composition of the carbonatisation cake was determined, and the organic contamination of the carbonatisation cake and calcine in contact with water was determined. In addition, TGA, DTA, XRD, SEM-EDX, BET, FTIR, density, pHzpc and particle size distribution were analyzed for carbonatisation cake, product and post-phosphate removal calcined product. Batch experiments were performed to determine the effect of dose, phosphorus concentration, temperature and contact time on phosphorus removal from aqueous medium. Maximum phosphate adsorption capacity was found to be 65.16 mg g−1 at 25 °C, pH of 6 and adsorbent dosage of 1 g L−1 for a contact time of 180 min. Adsorption experiments were applied to adsorption isotherms. Kinetic, thermodynamic and mass transfer calculations were calculated. The results show that calcines produced by heating the carbonated cake to 600 °C, which is not cost-effective in sugar production, can be used effectively to remove phosphate from wastewaters.

Measuring Investment Skill in Multi-Asset Strategies: An Empirical Study of the Information Coefficient as Weighted Rank Correlation

Over the past decade, the investment industry has come to appreciate the importance of asset allocation and its role in achieving clients’ financial objectives. The result has been a profound change in the landscape for the industry in terms of both product design and distribution. Increasingly, the asset flow to investment managers has been heavily driven by multi-asset funds and balanced funds rather than individual stock or bond funds. With the growing prominence of multi-asset investing, the role of active asset allocation has also become more important. For investors who are evaluating multi-asset funds and for asset allocators trying to set expected asset allocation alpha, the measurement of asset allocation skill is a crucial task. To the latter end, this article provides an intuitive methodology to measure asset allocation skill within the formal context of the fundamental law of active management, a well-known characterization of portfolio managers’ alpha generation process. Specifically, the authors show how weighted rank correlation provides an intuitive and transparent version of the information coefficient. Their study is framed within a novel simulation-based framework that they use to analyze the impact of asset allocation skill and its implications for estimating reasonable expectations of asset allocation alpha. <b>TOPICS:</b>Portfolio construction, exchange-traded funds and applications, performance measurement, statistical methods <b>Key Findings</b> ▪ Weighted rank correlation provides an intuitive and nuanced way to express the information coefficient—the relationship between <i>ex ante</i> and realized returns. ▪ The bespoke simulation framework described in the article can provide insight into the relationship between different skill levels and expected asset allocation alpha. ▪ We find that there is a near-linear relation between asset allocation skill and alpha and asset allocation skill and tracking error, but a less-than-linear relationship between asset allocation skill and information ratio and asset allocation skill and bet size. The relationship between asset allocation skill and trading frequency is found to be more or less uniform.

\u201cIt started 30\u2009years ago, and it still haunts me\u201d: an exploratory investigation of Territorians\u2019 gambling behaviours, harm, and help-seeking for gambling issues in an Australian jurisdiction

BackgroundThere is a lack of qualitative gambling research on lived experience, help-seeking, and gamblers and affected others’ views on the regulatory environment in the Northern Territory (NT), Australia. This study provides 1) lived experience of individuals who reported experiencing harms from gambling, 2) insights into help-seeking for gambling issues, 3) and people’s views on current legislation on gambling in the NT. The results of this study begin to establish an evidence base that could be used to inform targeted interventions for people experiencing harms from gambling in the NT.MethodsSemi-structured interviews were conducted with a targeted selection of respondents from the 2015 and 2018 NT Gambling Prevalence and Wellbeing Surveys. The sample (n = 27; age 18+ years; Aboriginal (The term of ‘Aboriginal’ has used been used throughout the manuscript to reflect Aboriginal and Torres Strait Islander, Indigenous, or First Nations people for purposes of brevity. We respect the diversity among these populations.) and Non-Aboriginal) included weekly (online and venue-based electronic gambling machine (EGM)) gamblers, non-regular gamblers, and those negatively affected by others’ gambling. A Framework Analysis approach was used for data analysis. Appropriate ethics approval was obtained.ResultsNegative impacts and harms from gambling were experienced by both gamblers and non-gamblers. These included monetary losses, relationship conflicts, emotional distress, and decrements to health. A lack of self-realisation of gambling issues and awareness of the available services, shame, and embarrassment, were reported as the main barriers to help-seeking. Where help was sought, it was primarily informal (e.g., family) and was rarely preventive. In many instances, self-help strategies were successful in controlling one’s own gambling. Gamblers suggested regulations should set limits on the daily number of hours of playing, the bet size, and reduced access to EGM. The need for strengthening the existing awareness and education interventions was emphasised.ConclusionsViewing the findings from a public health lens, targeted approaches based on specific circumstances may have the potential to minimise harms from gambling, but only for those already experiencing harms. The treatment, policy, and regulatory approaches need to be tailored to address the causes and impacts of harms experienced by people.

Effect of short time ball milling on physicochemical and adsorption performance of activated carbon prepared from mangosteen peel waste

This study investigates the short time ball milling effect on surface properties of activated carbon.(AC) produced from mangosteen peels (MP) waste and its subsequent effects on adsorption of cationic methylene blue (MB) from aqueous solution. AC was synthesized from MP waste under mild experimental conditions and was ball milled for a short time (30 min–120 min) at 350 rpm. The physicochemical properties of ball milled AC (BMAC) were investigated using BET, FTIR, TGA, FESEM, XRD and particle size distribution analysis. Various experimental results revealed that MB adsorption on BMAC was greatly influenced by basic pH, contact time and high temperature. The adsorption capability of BMAC was found to increase with decreasing particle size with ball milling. Kinetics study revealed that the adsorption capability of BMAC was best represented by pseudo second order kinetic model and adsorption equilibrium was well described by Langmuir isotherm. The adsorption process was endothermic and spontaneous as revealed by thermodynamic study. Overall, this work demonstrated that ball milling decreases the particle size of AC, increased its efficiency for adsorption of dye, and opened new ways for activation of AC using the ball-milling technique.

Adsorbent selection for pesticides removal from drinking water

ABSTRACT Pesticides present in water resources can cause adverse health effects even in low concentrations, due to their bio-accumulative character. Therefore, the challenge for drinking water production increases, due to the limitations of conventional water treatment technologies in the removal of small molecular weight dissolved compounds. This work aimed to provide technical and scientific support for the selection of pulverized activated carbon – PACs, granular activated carbon – GACs, and carbon nanotubes – CNT concerning atrazine – ATZ, simazine – SMZ, and diuron – DIU adsorption for application in water treatment plants, considering two forms of application commercial product – CP and analytical standard – SD. These forms of application were tested aiming to verify the influence of the purity of the products used in experiments on the adsorption efficiency. It was possible to verify the adsorption efficiencies were not guided only by the characteristics of the adsorptive materials used, and that the selection should not be carried out only based on the, specific superficial area – BET size and distribution of specific pore volume. The isotherms demonstrated that the parameter Kf associated with the results of the selection experiment can be considered an alternative technical tool of simple application and sufficient for this purpose. Also, the capacity of activated carbons – ACs and nanomaterials – NMs were affected by the application of the compounds, highlighting the importance of using commercial product – CP in scientific research and technical investigations. Hightlights The pesticides efficiency removal was affected due to the forms of application, SD and CP; The parameters IN and MBI were not decisive in the selection of the activated carbon; The main adsorption mechanism in all the materials was chemical; GAC was the most efficient adsorbent in the removal of the pesticides; An adequate adsorbent selection is crucial for satisfactory removal of pesticides in water.

Study on the Influence of Diatomite with Different Shapes on the Moisture Absorption and Release Performance in Changbai Region of Jilin Province

In this paper, different morphologies of diatomaceous earth (disc, cylindrical) were purified, and characterized by SEM, BET and pore size distribution, and moisture absorption and desorption tests were carried out. The results show that the humidity control performance of the cylindrical diatomite sample is better than that of the disc-shaped diatomite sample. Its 24h moisture absorption, 24h moisture release, volumetric moisture content ratio, average volumetric moisture content and other indicators all exceed Disc-shaped diatomite samples; the specific surface area of cylindrical diatomite samples is higher than that of disc-shaped diatomite samples, and the pore size distribution is more reasonable. Combined with the analysis of humidity control performance, cylindrical diatomite samples are more suitable As an excellent humidity control material.

Adverse Selection and Liquidity: From Theory to Practice

This paper shows how to map predictions of theoretical models of market microstructure into operational empirical measures of liquidity. A meta-model implies an empirical measure of liquidity, denoted L, which describes various characteristics of trading and funding liquidity such as trading costs, bet sizes, haircuts, and capital requirements. When mapped into existing models of adverse selection, the meta-model also describes precisely how adverse selection shows up in pricing accuracy and resiliency. The meta-model is consistent with models of both block trading and flow trading. It highlights a deep connection between time and adverse selection.

The structural connectivity of subthalamic deep brain stimulation correlates with impulsivity in Parkinson's disease.

Subthalamic deep brain stimulation (STN-DBS) for Parkinson's disease treats motor symptoms and improves quality of life, but can be complicated by adverse neuropsychiatric side-effects, including impulsivity. Several clinically important questions remain unclear: can 'at-risk' patients be identified prior to DBS; do neuropsychiatric symptoms relate to the distribution of the stimulation field; and which brain networks are responsible for the evolution of these symptoms? Using a comprehensive neuropsychiatric battery and a virtual casino to assess impulsive behaviour in a naturalistic fashion, 55 patients with Parkinson's disease (19 females, mean age 62, mean Hoehn and Yahr stage 2.6) were assessed prior to STN-DBS and 3 months postoperatively. Reward evaluation and response inhibition networks were reconstructed with probabilistic tractography using the participant-specific subthalamic volume of activated tissue as a seed. We found that greater connectivity of the stimulation site with these frontostriatal networks was related to greater postoperative impulsiveness and disinhibition as assessed by the neuropsychiatric instruments. Larger bet sizes in the virtual casino postoperatively were associated with greater connectivity of the stimulation site with right and left orbitofrontal cortex, right ventromedial prefrontal cortex and left ventral striatum. For all assessments, the baseline connectivity of reward evaluation and response inhibition networks prior to STN-DBS was not associated with postoperative impulsivity; rather, these relationships were only observed when the stimulation field was incorporated. This suggests that the site and distribution of stimulation is a more important determinant of postoperative neuropsychiatric outcomes than preoperative brain structure and that stimulation acts to mediate impulsivity through differential recruitment of frontostriatal networks. Notably, a distinction could be made amongst participants with clinically-significant, harmful changes in mood and behaviour attributable to DBS, based upon an analysis of connectivity and its relationship with gambling behaviour. Additional analyses suggested that this distinction may be mediated by the differential involvement of fibres connecting ventromedial subthalamic nucleus and orbitofrontal cortex. These findings identify a mechanistic substrate of neuropsychiatric impairment after STN-DBS and suggest that tractography could be used to predict the incidence of adverse neuropsychiatric effects. Clinically, these results highlight the importance of accurate electrode placement and careful stimulation titration in the prevention of neuropsychiatric side-effects after STN-DBS.

Development of porous nickel catalysts by low-temperature Ni–Al chemical alloying and post selective Al leaching, and their application for ammonia decomposition

Micron-sized Ni–Al alloy powders (Ni–x wt.%Al, x = 40, 50, 60) were synthesized using the low-temperature chemical alloying (LTCA) at 500 °C. The three different as-prepared Ni–Al alloy powders were composed of Ni2Al3 and/or NiAl3 phases while achieving thermodynamic equilibrium compositions (Ni–40 wt%Al, Ni2Al3; Ni–50 wt%Al, the coexistence of Ni2Al3 and NiAl3; Ni–60 wt%Al, NiAl3). The LTCA method demonstrates that it is capable of producing Al-rich Ni–Al alloy powders while maintaining a particle size similar to that of the starting Ni particles. The three Ni–Al alloy powders were used as precursor materials to fabricate porous nickel catalysts through a selective aluminum leaching process, followed by the enlargement of the surface area. Alteration of the material characteristics with respect to the leaching time was investigated using XRD, FESEM-EDS, TEM, XPS, TPR, BET, and particle size analysis. The nickel skeletal catalysts with the increased BET-surface areas (50–111 m2/g) displayed high reactivity toward ammonia decomposition.

Synthesis and characterization of nano Mn3O4 and LiMn2O4 spinel from manganese ore and pure materials

Extraction of nano materials form natural ores is considered as an interesting point of research. The present work focuses on preparation of nano Mn3O4 from two different sources, namely; manganese ore and pure chemicals. Mn3O4 leached from manganese ore or that prepared from pure chemicals were utilized for preparation of LiMn2O4 spinel by solid state method. The prepared oxide and spinel materials were investigated by XRF, XRD, TEM, SEM, BET and particle size distribution. The results revealed that the percentage of Mn3O4 reached 82% for that leached from manganese ore and 99.1% for that prepared from pure chemicals. Both of them exhibited needle-like particles with comparable size of several nanometers; at least in one dimension. The analysis of manganese oxide leached from manganese ore exhibited Mn3O4, iron oxide and some impurities while that prepared from pure chemical displayed only pure Mn3O4. LiMn2O4 spinel and excess manganese oxide were detected in the sample prepared using pure Mn3O4 while only LiMn2O4 spinel phase was detected in the sample prepared using oxide leached form manganese ore. The particle size of LiMn2O4 prepared from pure Mn3O4 (50 nm - <1 μm) was smaller than that prepared from oxide leached from manganese ore (100 nm - 2 μm). Consequently, the surface area of LiMn2O4 prepared from pure Mn3O4 was higher than (9.32 m2/g) that prepared form leached Mn3O4 (2.34 m2/g).

Influence of hydrocarbons on hydrogen chloride removal from refinery off-gas by zeolite NaY derived from rice husks

The removal of gaseous hydrochloric acid (HCl) in refineries and petrochemical plants is essential to prevent potential catalyst poisoning, equipment corrosion, and several associated public health and environmental hazards when the acid contaminates the hydrogen–hydrocarbon feedstock. In the present work, the effect of alkanes, alkenes, and liquid aromatic hydrocarbons on the removal of HCl from refinery off-gas using zeolite NaY was evaluated. Zeolite NaY was synthesized from rice husks via a hydrothermal route. Adsorbent characterization analyses such as XRD, SEM-EDS, FT-IR, BET and particle size distribution were employed. Fixed-bed experiments were operated under feed condition of 600 ppm HCl and gas hourly space velocity of 640 mL/h·cm3. Gaseous HCl was combined with H2, H2-alkanes and H2-alkenes to simulate the main components of refinery-off gas. Experimental breakthrough curves were used to determine the adsorption capacities of zeolite NaY pellets at breakthrough and saturation. HCl removal by fresh zeolite NaY was inhibited by light alkanes but improved in the presence of alkenes. The adsorption capacity at breakthrough for fresh zeolite with combined hydrogen and light alkenes was measured at 0.1507 g/g. In the presence of aromatics, significant reduction in adsorption capacities to 0.1247, 0.1379 and 0.1437 g/g were obtained for adsorbents subjected to H2, H2-alkanes and H2-alkenes respectively. Zeolite NaY consistently showed higher performance for HCl removal in the presence of H2 feed mixed with light hydrocarbons compared with a commercial adsorbent.

Impulsive Sports Betting: The Effects of Food or Substance Consumption.

The present study aimed to explore how food or substance consumption (e.g., experiencing hunger, or having consumed alcohol or recreational drugs) could shape consumer impulsive spending on sports betting products. Based on a large online sample of Australian sports bettors, we found that participants with higher hunger level, or having consumed more alcohol or recreational drugs, tended to have increased impulsive bet size. These impulsiveness effects had both direct and indirect effect components. The significant direct effects confirmed that positive relationships directly existed between hunger, alcohol consumption, or recreational drug consumption and impulsive bet size, even when all potential mediators and covariates were statistically controlled. Moreover, results regarding specific indirect effects demonstrated that hunger, alcohol consumption, or recreational drug consumption was also indirectly linked with impulsive bet size, via their relationships with both promotional and financial influences, rather than social influences. Furthermore, participants' Problem Gambling Severity Index score was positively associated with their impulsive bet size. These findings support and complement the literature on impulsivity as well as the research on strategies for staying in control of gambling, and have implications for consumers, regulators, and treatment/help providers.

Investigation of adsorption of metronidazole on Chitosan - Halloysite nanocomposites and controlled release

A novel nanocomposite drug carrier composing from chitosan (CTN) and halloysite nanotubes (HNTs) has been developed. For this purpose, the metronidazole (MNZ) is chosen as a model drug. The characterization of synthesized nanocomposites is performed by FTIR, TGA, DSC, SEM, TEM, BET and particle size distribution analysis. MNZ is loaded to chitosan-halloysite (CTN-HNT) nanocomposites in two ways; by direct loading and adsorption method. The adsorption of MNZ on CTN-HNT nanocomposites have been investigated as a function of medium pH, mass ratio of CTN to halloysite (HNT), amount of nanocomposite and drug concentration. The fit of MNZ adsorption equilibrium on CTN-HNT nanocomposites to the Langmuir and Freundlich models was investigated. The adsorption kinetics of MNZ on nanocomposites have been evaluated using the pseudo-first order rate equation of Lagergren and the pseudo-second-order rate equation of Mc-Kay and Ho. The controlled release of MNZ from CTN-HNT nanocomposites has also been investigated.

An empirical investigation of wagering behavior in a large sample of slot machine gamblers

Using individual transaction gambling data from a casino, we examine the existence of positively or negatively autocorrelated betting behavior in a panel of 42,669 gamblers observed over a period of 108 consecutive days encompassing over 17 million slot machines plays. The statistical analysis suggests that gamblers increase their bet sizes significantly more after win streaks, with the largest increase occurring after three wins in a row. This increase in bet size following win streaks remains significant after variables are introduced for demographics, wealth, habit, house money effects, time spent gambling and account balance, gambling excitement, and player fixed effects. Although ultimately we cannot definitively separate out the influence of win streaks from wealth effects, increasing the amount bet following a win streak is not inconsistent with a hot hand belief that another win is more likely on the next spin.

Utilization of silica–chitosan nanocomposite for removal of 152+154Eu radionuclide from aqueous solutions

Nano-silica (Si-AL800) was extracted from the thermally treated rice husk ash by acid leaching route. Coating surface of the extracted silica with chitosan gel was done by a direct mixing to produce silica–chitosan nanocomposite (Si-AL800-chitosan). The resulting samples were examined by different analytical techniques such as SEM, TEM, XRD, BET, TGA/DTA, FT-IR and pore size distribution. The adsorption efficiency of samples towards removal of 152+154Eu radionuclide was investigated under different variables. A maximum capacity of 160 mg/g was found at pH of 5 and 298 K. The order of reaction mechanism is described by pseudo-second order.

Encouraging Gamblers to Think Critically Using Generalised Analytical Priming is Ineffective at Reducing Gambling Biases.

Gambling has been associated with an array of fallacious beliefs that foster risky gambling decisions. Research into other belief systems suggests that the endorsement of non-evidence based beliefs, such as the paranormal or conspiracy theories, can be reduced when people think more analytically. The purpose of this study was to explore whether an intervention designed to elicit analytical thinking was effective in altering the gambling beliefs and simulated gambling behaviour of 178 regular electronic gaming machine (EGM) gamblers (102 males, 76 female). Participants were randomly allocated to complete either an analytic or a neutral priming task, followed by completion of belief measures (erroneous and protective) and play on a simulated EGM game. Results failed to show that priming for analytical thinking changed betting on an EGM; including features of bet size, bet change, persistence and theoretical losses. Contrary to expectations, results suggest that priming analytical thinking using generalised interventions does not appear to be effective in altering peoples' simulated gambling involvement or gambling beliefs. In fact, priming people to think more critically might be counterproductive by contributing to greater positive expectations about gambling outcomes. The results further suggested that the number of times a player alters their bet is a good indicator of theoretical gambling losses and is associated with irrational gambling cognitions. Interventions designed to promote safer thinking in gamblers should be implemented with care, as results from our study suggest that encouraging critical thinking in at-risk or problem gamblers may not be effective in reducing risky gambling.

The effects of alcohol on sequential decision-making biases during gambling.

Gambling and alcohol use are recreational behaviours that share substantial commonalities at a phenomenological, clinical and neurobiological level. Past studies have shown that alcohol can have a disinhibiting effect on gambling behaviour, in terms of bet size and persistence. This study was conducted in order to characterise how alcohol affects biases in judgment and decision-making that occur during gambling, with a focus on sequential decision-making including the gambler's fallacy. Sequential biases were elicited via a roulette-based gambling task. Using a standard between-groups alcohol challenge procedure, male participants played the roulette task 20 min after receiving an alcoholic (0.8 g/kg; n = 22) or placebo (n = 16) beverage. The task measured colour choice decisions (red/black) and bet size, in response to varying lengths of colour runs and winning/losing feedback streaks. Across both groups, a number of established sequential biases were observed. On colour choice, there was an effect of run length in line with the gambler's fallacy, which further varied by previous feedback (wins vs losses). Bet size increased with feedback streaks, especially for losing streaks. Compared to placebo, the alcohol group placed higher bets following losses compared to wins. Increased bet size after losses following alcohol consumption may reflect increased loss chasing that may amplify gambling harms. Our results do not fit a simple pattern of enhanced gambling distortions or reward sensitivity, but help contextualise the effects of alcohol on gambling to research on decision-making biases.

Determination and quantification of heavy metal ion by electrochemical method

Today’s environment is polluted by heavy metal ions and toxic substances. The lead (Pb2+) is one of them which affect the environment by both natural and anthropogenic ways. Protection of the environment needs proper determination and quantification of these metal ions. Thus developing proper sensor with less cost is the focus of present research. Electrochemical sensor has attracted a great attention to determine these hazardous elements. In the present work sensor modified by blast furnace slag (BFS), provides a new opportunity for enhancing the electrocatalytic performance of fabricated sensor. The BFS was characterized by SEM, XRD, BET and particle size analyzer. Moreover different compositions of BFS were use to optimize the slag ratio. Furthermore the sensor modified material characterized by CV, Chronocoulometry, EIS and DPV. The electrochemical response towards Pb2+ on BFS modified sensor was explored by CV, EIS and DPV. Transfer coefficient (α) was calculated as 0.664 and rate constant (Ks) 1.08 s−1. The electrode was linear in the concentration range of 1–5 μM (R2 = 0.99). Experimental parameter like pulse height, step height, pH were also optimized. Detection and quantification limits were calculated as 0.015 μM and 0.053 μM respectively. This detection limit for Pb2+ is lower than the permissible limit provided by W.H.O. for drinking water. The electrode shows high sensitivity of 1068 μA/μM−1 cm-2 for Pb2+ ions with superior reproducibility and repeatability. The results suggested that blast furnace slag was a better material for heavy metal ion in aqueous solutions.

Precipitation, characterization, and kinetic modeling of calcium carbonate prepared using sodium myristate

Sodium myristate was used in the calcium carbonate precipitation process to investigate its potential as a crystal morphology modifier and its effect on the end-product characteristics. Calcium carbonate was precipitated with and without different concentrations of sodium myristate and the resulting crystals were evaluated using XRD, SEM, FTIR, BET, and particle size analysis. XRD and FTIR analysis revealed that the as-obtained crystals were in the form of calcite. A significant increase in the specific surface area was observed upon increasing the concentration of sodium myristate and the morphology of the calcium carbonate crystals changed from smooth to rough, smaller cubic-like particles. Contact angle measurements showed that the crystals prepared using 50 ppm sodium myristate have good hydrophobic properties. The calcium carbonate crystals were characterized using TGA and their thermal decomposition kinetics investigated. The thermal decomposition data were evaluated using different model-free kinetic models, such as FWO, KAS, and Starink. The average activation energy of calcium carbonate during the thermal decomposition process was found to be in the range of 147–188 kJ/mol, which decreased by ∼10% when sodium myristate was added to the precipitation process. Thus, sodium myristate can be used as the crystal size and shape modifier in the calcium carbonate precipitation process.

Optimal Risk Budgeting under a Finite Investment Horizon

The Growth-Optimal Portfolio (GOP) theory determines the path of bet sizes that maximize long-term wealth. This multi-horizon goal makes it more appealing among practitioners than myopic approaches, like Markowitz’s mean-variance or risk parity. The GOP literature typically considers risk-neutral investors with an infinite investment horizon. In this paper, we compute the optimal bet sizes in the more realistic setting of risk-averse investors with finite investment horizons. We find that, under this more realistic setting, the optimal bet sizes are considerably smaller than previously suggested by the GOP literature. We also develop quantitative methods for determining the risk-adjusted growth allocations (or risk budgeting) for a given finite investment horizon.