Unwanted Elements Research Articles

Mechanical and Thermal Analysis of Topological Optimization for Load Bearing Skate

Load bearing skate for the current weight is heavy and requires its own weight, but persist without improvement in the lack of capital and technology, but it is a reality. In this study, carried out phase optimal design to remove unwanted elements that do not have a stress to reduce the weight of skating that is being used for cargo transportation for, it reduces the weight of the objective function, we examined the safety associated with it.Using the FEM analysis Let's examine the effect on the failure strength by extreme temperatures that are used in the field of stress concentration due to discontinuity in the analysis at the time, structure - was carried out thermal analysis.Further, while ensuring safety through safety factor 2.1 and 20% weight reduction by the phase volume of for weight reduction.

Identifying possible associations of minor and trace elements with major elements in Jamaican hillside and catchment bauxites using multivariate analysis tools

Over the past 50years the quality of Jamaica’s mined bauxites has gradually changed from gibbsite/hematite dominated ores to ones that contain more boehmite and goethite and have higher concentrations of many minor and trace components. This presents evolving challenges to the Bayer process industry which must still meet the aluminum smelting industry’s alumina quality requirements. The extraction of unwanted elements from bauxite into the caustic liquors depends on their host minerals but routine X-ray diffraction methods used by the industry are often unable to identify minerals for minor and trace elements and therefore do not give indications of potential Bayer liquor contamination by such elements. We sought to combine elemental concentrations and qualitative X-ray diffraction information with factor and cluster analyses to identify the probable associations of minor and trace elements with major elements and so predict their likely dissolution properties. Bauxites (178) were selected from catchment (32; gibbsite/hematite) and hillside (146; gibbsite/boehmite/goethite) deposits based on exploration data and reanalyzed using a variety of analytical techniques. The quality of the data was assessed and then the data were transformed to centered lognormal ratios to allow for their compositional nature. The elemental data used in the factor analyses were limited to Al, Fe, Ti, Si, Ca, P, V, Cr, Mn and Zn (plus Mg and Zr for the catchment bauxite set) because of missing data for some bauxites. For both bauxite types 80% of the variability was accounted for within three factors. The hillside bauxites’ factors associated Al with Fe, Ti, V and possibly Cr, Mn with Zn and Ca with P while Si showed no associations. The catchment bauxites’ factors were similar except for the Ca–P link being weak and Ca possibly having a linkage with Si; Zr joined the Al–Fe–V–Ti–Cr group and Mg linked weakly with Ca. The cluster analyses included the above elements plus Sr, Ga, Pb, As, Sc, Co, Cu, Cd, Hf, La, Ce, Nd, Sm, Yb, Th and U and used Pearson correlation coefficients as distance measures to allow for the missing values. The identified clusters separated Al from Fe, particularly for the hillside bauxites, confirmed the isolation of Si, suggested minimal associations for Cr, confirmed the Mn–Zn associations, particularly within the catchment bauxites, and indicated that P was not associated with Ca in the catchment bauxites and only weakly associated in the hillside ores. These identified associations allow for predictions about the dissolution processes and potential Bayer liquor contamination. Our future work will seek to confirm these predictions and refine the models.

Predictive-repetitive control with constraints: From design to implementation

This paper addresses the design and implementation of predictive-repetitive control systems, including the case when constraints are imposed. The approach is based on a frequency response decomposition technique that detects the dominant frequency components of the reference signals and embeds them in the predictive-repetitive controller. Analysis and design make use of the frequency response of the closed-loop system and the choice of the structure of the repetitive controller is considered as a balance between the reduction of tracking errors and minimization of the effects on performance of unwanted elements, such as model uncertainty. The implementation of operational constraints on the amplitudes of the control signals, their increments and on the outputs is considered using an on-line solution constructed using quadratic programming and the identification of active constraints. Experimental results from application to a 2 degree-of-freedom robotic system are used to illustrate the design and implementation procedures developed.

Determination of arsenic and mercury level in scalp hair from a selected population in Penang, Malaysia using XRF technique

As with many cities all over the world with active industrial developments, the city of Penang in Malaysia has also the potential of being exposed to industrial pollution. Such exposure would certainly have a detrimental impact on the environment and the people. The determination of trace elemental levels in hair which is well known as a method for environmental exposure monitoring, evaluation of heavy metal poisoning, assessment of nutrient levels and disease diagnoses. In this study, it is selected as the method to determine the possible exposure to pollutants in the form of unwanted trace elements. The natural levels of trace elements in hair are hence monitored first as reference values for the assessment of the possible human contamination levels. In this work the concentrations of As and Hg in the human scalp hair of 100 residents of Penang were determined using XRF. The results of this study are compared with the results obtained in other cities where such measurements have also been carried out.

Distribution of bismuth between copper and FeOx–CaO–SiO2 slags under copper converting conditions

Ferrous calcium silicate (FCS) slags (FeOx–CaO–SiO2) have been proposed for use in continuous copper converting, because they attack refractories to a much lesser extent than calcium ferrite slag. However, their ability to absorb unwanted minor elements, such as bismuth, from the molten copper is less well known. Bismuth in copper anodes causes problems in the electrorefinery, while in finished copper products it adversely affects their mechanical properties. In this work, the distribution ratio of bismuth between copper and copper saturated FCS slags at 1300°C and an oxygen partial pressure of 10−7 MPa (10−6 atm) was determined by three-phase equilibration. Copper entrainment in slag caused difficulties during data analysis. It was found that the slag/metal bismuth distribution ratio decreased as the CaO content of the slag increased but was much less affected by the Fe/SiO2 (w/w) ratio. The inferred distribution ratios were projected onto the FeO–CaO–SiO2 phase diagram, as was the calculated value of the limiting activity coefficient of BiO1·5 in the slags. The strong similarity between the way in which both bismuth and copper distributions are affected by the slag composition, as well as theoretical considerations, show that BiO1·5 behaves in slags as a neutral metal oxide. As a result, bismuth removal from blister copper is maximized with FCS slags of low CaO content, the Fe/SiO2 (w/w) ratio being relatively unimportant.

Evaluation of ultrafiltration membranes with the multimedia filter/ultrafiltration/reverse osmosis/NH3-N remover system to treat surface water

This study discussed the feasibility for the multimedia filter/UF/RO/NH3-N remover system to treat river Tang surface water, and three different polysulfone (PSf) membranes with molecular weight cut off of 80, 100, and 300 kDa were tested to select a UF membrane for low membrane fouling, higher flux, low transmembrane pressure and better quality of the permeate. The results showed that the multimedia filter/UF/RO/NH3-N remover combined system was able to remove all unwanted elements and to produce consistent and high-quality water. For the whole experiment, K of RO system basically stabilized at 2.8 L/m2 h·bar. RO system could effectively remove NH3-N and conductivity. Comparing results from three UF membranes experiments, it was found that three UF membranes could remove particles (colloids) and the 100 kDa PSf membrane was the most suitable membrane to treat the river Tang.

Repression towards Catholic Clergy from Lublin Diocese during German occupation 1939-1945

SUMMARYIt is essential to know the history of Catholic Church in Poland during German occupation when it comes to exploration of aggregate history of Polish nation in this difficult time. The issue of repression against Polish clergy from Lublin diocese by German authorities in years 1939-1944 and powers of Third Reich, was presents in various aspects, in many scholarly articles, monographs and group works. However, the aforementioned publications do not exhaust basics to educate foil and fair-minded view on this problem.German army went in to Lublin on 18 September 1939, after dramatic defense of the citizens.After the short time of reign of Wehrmacht units, on 26 October 1939, Führer proclaimed his decree on creating administrational entity called Generalna Gubernia, which involved four regions, including lubelski region with Lublin as its capital. This decree embraced the area of pre-war Lubelskie Voivodeship. The occupation authority’s division of administration did not violate the structure of deanery in the diocese. However, under the new circumstances, deans and rectors had difficulties executing administrational functions. When the Lubelski District was created. Bishop Marian Leon Fulman and suffragan, Bishop Władysław' Goral wielded authority in this area.It is necessary to mention that bloody operations of the police and SS are especially remembered in the history of Church in Lublin and the whole area. These two bodies were executing the most important strategic tasks within the scope of ‘maintaining order’, prevention, requital, or even genocide and extermination. This group was led by SS- Brigadeführer Odilo Globocnik (till September 1943) and SS-Gruppenführer Jacob Sporrenberg.The most significant German operations, when it comes to repression of catholic clergy in, the Lubelski District are repressive or intimidating actions.In the Lubelski District, occupation authorities applied the same methods of repression and extermination both to all citizens and clergy. Lublin’s clergymen were dying in executions, they were taken as hostages, arrested and send to concentration camps. Hie repression involved priests on every level of church hierarchy. What is more, it must be said that only Polish bishops out of all occupied countries were arrested and taken to concentration camps.In the Lubelski District, the main place where the people were arrested was Lublin and prison of Security Police and Security Service. Prison on the Castle, as it was called, was subdued to the leader of SS and the police in the district. The prison m Lublin was without undoubtedly a place of terror and attrition of prisoners held in it on the mass scale. This prison became the place of direct extermination where executions were done by firing squad, hanging, or even by gassing. Executions had unitary or mass character, they were sometimes done in a company of eyewitnesses, but usually they were confidential, performed at night or in the morning.The first ‘purifying’ action of intelligentsia, which started with arrests in November and was follow ed by verdicts of executions for bishops and the execution itself on 23 December, was perceived by the leaders of SS and the police, Odilo Globocnik, as fight with leading layer of society, who could potentially organize actions against German authorities, they could give signal to ruthless fight with ‘unwanted elements’. Repressions took place on the local scale, because they involved only people from Lublin or from area around Lublin. The way in which this action was prosecuted indicates that it was chaotic strike, because the enforcement authority which held power at the beginning of the November did not have full records of the intelligentsia.Globocnik considered Catholic Church an important monument of Polish national spirit, so he began the purging of the district by first destroying the Church. It can be validated by the three mass arrests of clergy on 9 Nov, 11. Nov and 17 Nov 1939.The effect of the policy realized by Odilo Globocnik is presented in statistics relating to repressing of clergy in years 1939-1945. 200 out of 459 priests from Lublin diocese in 1939 fell victim to German terror.

The Evolution of Multiple Resistant Strains: An Abstract Model of Systemic Treatment and Accumulated Resistance

The proliferation of resistant strains has been an unintended side effect of human interventions designed to eliminate unwanted elements of our environment. Any attempt to destroy an adaptive population must also be considered as a selection pressure, so that the most resistant members will comprise the next generation. Procedures have been developed to slow the evolution of resistances in a population, with the most common approaches being overkill and treatment cycling. This paper presents an agent-based Susceptible-Infection-Susceptible (SIS) model to explore the effectiveness of these procedures on an abstract epidemic of pathogens, focusing on how the interaction between interventions and mutations affects acquired resistance. Illustrative findings indicate that overkill performed better than cycling treatments when variation in resistances had a high degree of heritability. When resistance variation was effectively memoryless, cycling and overkill performed comparably. However, overkill was prone to backlash outliers where an amplification of infection resistance occurred- a significant drawback to the overkill technique. These backlash events indicate that cycling interventions might be more effective when variation is memoryless and carrying resistance incurs a cost to overall fitness. However, under limited fitness-cost conditions explored, cycling performed no better than overkill for preventing resistance.

Recycling of Exhausted Batteries and EAF Dusts by Leaching with Several Aqueous Media

Zinc is a base metal present in several products of general use, and therefore found in numerous residues and end-of-life products. The two main sources of zinc containing wastes are spent Zn-MnO2 portable batteries and electric arc furnace (EAF) dusts from steelmaking plants. The recovery of metals from these residues by appropriate recycling processes is mandatory due to environmental, economic and resource conservation issues. Concerning the similar composition of both residues, their simultaneous processing can be envisaged. The research herein described consists on the hydrometallurgical treatment of zinc bearing waste, where several leaching routes for solubilising metals, mainly zinc, are studied. The leaching of shredded batteries and EAF dusts was carried out using three different leaching solutions containing sulfuric acid, hydrochloric acid or ammonium chloride. The acid leaching of zinc in the oxide form (zincite) using both acids, was very efficient and quick, allowing the recovery of practically all Zn contained in batteries and about of 80% of Zn in dusts. Regarding to the leaching media the behaviour of lead oxides present in dusts was different, being insoluble with H2SO4 and partially soluble with HCl (40-90% yield, depending on conditions). For battery waste stream, manganese is also other important metal, which oxides were only partially soluble in acid media, attaining a maximum leaching yield of 90% Mn. Iron, considered a contaminant in both residues, was partially leached and required further purification steps. The use of an ammoniacal medium (NH4Cl) was very selective for zinc, being iron practically insoluble. However, the maximum zinc leaching yield attained for both residues was only near 60%. Under these conditions, manganese contained in batteries was very insoluble while lead from dusts was leached up to 70% due to the relative solubility of lead chloride. This research showed that hydrometallurgical treatment can provide versatile solutions for recycling metals from Zn waste. Ammoniacal leaching allows high selectivity for zinc but less recovery efficiency is attained, while acid leaching allows higher metal recovery yields but unwanted elements like iron are co-dissolved.

Drugs influencing orthodontic tooth movement: An overall review

Orthodontic treatment is based on the premise that when force is delivered to a tooth and thereby transmitted to the adjacent investing tissues, certain mechanical, chemical, and cellular events take place within these tissues, which allow for structural alterations and contribute to the movement of that tooth. Molecules present in drugs and nutrients consumed regularly by patients can reach the mechanically stressed paradental tissues through the circulation and interact with local target cells. The combined effect of mechanical forces and one or more of these agents may be inhibitory, additive, or synergistic. Current orthodontic research aims to develop methods of increasing the tissue concentration of molecules promoting tooth movement, while simultaneously decreasing the concentration of unwanted elements which can produce harmful side effects. This article discusses in detail the various possible drugs that can bring about alterations in the desired orthodontic tooth movement.

Influence of leaching on the chemical composition of grassland biomass for combustion

AbstractBioenergy production from grassland biomass is an alternative use for semi‐natural grasslands, but chemical composition of grassland herbage can limit its suitability for combustion. Leaching by precipitation during the field period is currently used to remove unwanted elements from other herbaceous biofuels. The aims of this study were to assess the influence of leaching on chemical composition of grassland biomass, to establish the influence of leaching intensity and to evaluate the feasibility of a simplified laboratory method for leaching studies. Freshly cut and dried herbage from two contrasting grasslands were leached using 12 and 36 mm of simulated rain. A second experiment compared three methods of different leaching intensity. Leaching resulted in strong reduction in Cl and K concentrations; ash was moderately reduced and Mg slightly reduced. Concentrations of N, S and Ca were not affected. Leaching occurred in dried, but not in fresh herbage, and Cl leaching was affected by herbage type. Cl, K and ash responded differently to increased leaching intensity. Slagging, fouling and corrosion problems during combustion, which are closely linked to Cl and K concentrations, could be reduced by natural leaching under suitable weather conditions. A standardized laboratory leaching method is suggested for further investigating the influence of herbage characteristics on the leachability of K and Cl.

Application of an Off‐Gas Analysing System to Control Oxidation during Stainless Steelmaking in an EAF

AbstractDuring stainless steelmaking in the electric arc furnace at Deutsche Edelstahlwerke GmbH, oxygen is injected to oxidize unwanted tramp elements mainly carbon and silicon. Unfortunately the injected oxygen also oxidizes valuable elements such as chromium and iron, which causes an economical loss and has a negative environmental effect. Since the temperature and dilution techniques to minimise chromium oxidation are seldom applied in the electric arc furnace, a new strategy to minimise chromium oxidation has to be developed. This paper proposes a new strategy which involves the use of a continuous off‐gas analysing system to minimise chromium oxidation by monitoring the oxidation products in the off‐gas, i.e. CO and CO2. During stainless steelmaking in the electric arc furnace, for which initial carbon and silicon input cannot be precisely known due to imprecise scrap analysis, the installed off‐gas analysing system should provide precise information concerning an efficient oxygen injection. This would then directly prevents excess chromium and iron oxidation. A continuous off‐gas analysing system installed at Deutsche Edelstahlwerke GmbH delivers a promising result for future applications. During the plant trial, the efficiency of oxygen injection as well as the chromium and iron yields were increased.

A kinetics model for Tb3+ recombinations in low doped Tb:Lu1.8Y0.2SiO5 crystals

The detailed characterization of the terbium related optical properties of low doped oxyorthosilicates of lutetium and yttrium is reported. The introduction of terbium ions generates an ultraviolet absorption band peaked at about 242 nm and line shaped emissions in the 350–600 nm range. The transitions are related to the D53 and D54 levels and the analysis of the decay time measurements allows to individuate a cross relaxation mechanism among Terbium ions. We propose a three level kinetic model which is able to reproduce the experimental data allowing to discriminate among the radiative and nonradiative contributions to the transitions in the case of low content of Tb ions (nominal content 10 ppm). The reported study addresses two important goals, providing, from one side, a detailed characterization of possible inorganic phosphors, and from the other side, since traces of unwanted elements were identified in numerous commercial samples of cerium doped oxyorthosilicates, it can contribute to increase the performance of scintillator devices by revealing the optical features of one of the more diffuse and critical impurities.

A Tunable Ionic Liquid Based RC Filter Using Electrowetting: A New Concept

RC filters are used to discriminate unwanted frequency elements of a specific signal. Here we report a new concept for a tunable RC filter. The concept was demonstrated by developing a tunable RC filter “consisting of an ionic liquid drop placed on a dielectric layer.” Cut-off frequency of the filter can be altered and controlled by changing the drop shape via electrowetting. The dielectric layer and the solid−liquid interface behave as serially connected capacitors, where the total capacitance is a function of drop shape (or contact angle). The drop shape and hence the total capacitance can be instantly controlled by electrowetting. The change in the capacitance will change the cutoff frequency of the filter. For a 5 μL ionic liquid drop, the achieved “tunability range” was 4.5−9.8 kHz. This demonstrates that the new concept is attainable. This RC filter system could potentially be used as a detecting technique.

A balancing act for autophagin

Autophagy is a tightly regulated catabolic process whereby cells degrade their constituents to dispose of unwanted cytoplasmic elements and recycle nutrients for cellular remodeling. Studies of autophagy in mammals have elicited substantial interest because it is linked to a range of physiologic and pathologic states. In this issue of the JCI, Mariño et al. uncover a role for autophagy in a balance disorder related to inner ear pathologies. Mice lacking the protease autophagy-related 4B (Atg4b, also known as autophagin-1) exhibited a systemic reduction in autophagy and showed defects in the development of otoconia, organic particles that contain calcium carbonate crystals and proteins and that are essential for balance perception (equilibrioception) in mammals. The intriguing aspect of this work is that an autophagy block impairs the secretion and assembly of otoconial proteins, emphasizing a role for autophagy in functions distinct from macromolecule degradation.

Lyden av mediering - En utforsking av nyere sjangertrekk innenfor filmtrailere [The sound of mediation - Exploring new aspects of the movie trailer genre

When it comes to experiencing traditional sound design in movies, the audience is often presented with hidden mediation and production processes: abrupt sound changes are softened, noise and annoying reverb are avoided, unwanted sound elements are reduced and desired sounds are amplified. Sound designers make these kinds of selections to enhance the illusion of continuity in an attempt to engage the audience. In most cases this means the sound designer will compose a sound track and furthermore the audience is not aware of the sound designer’s mediation and manipulation. In sharp contrast to this, many movie trailers include sound elements in which traces of the mediation process are clearly recognised and connected to various visual elements like camera movements, cuts, dissolves and speed variations like slow motion. The following discussion revolves around movie trailers and the use of sound elements that in themselves draw attention to the process of production and mediation, also involving a discussion of how the various sound elements function.

Beyond Expulsion

This article examines how the complexities of the Sudeten German expulsion and resettlement of the former Sudetenland spawned the notion that certain groups of people were unreliable or suspicious and, therefore, unwanted inhabitants. The intolerance and suspicion that setters, local and central officials, and others voiced toward different groups and actions directly related to the expulsion of Germans. The rapid influx of new settlers in search of German property and social mobility had a destabilizing effect on the region as well. The category of unwanted elements changed over time and reflected not necessarily the arrival of particular people but the problems unleashed by expulsion and settlement. The emergence of this category demonstrates how ethnic cleansing affected not only the targeted ethnic group but also how that process transformed people and places. This article offers new insights into the increasing body of literature on this topic in Central and Eastern European history by expanding the focus beyond Czechs and Germans. By examining a range of different sources, it also demonstrates that local actors as much as central ones created and sustained repressive attitudes in the borderlands.

Application of Extraction Chromatography for the Preparation of High Purity 111In for Medical Use

Indium isotopes, mainly In‐111, are frequently used in nuclear medicine, both in therapeutics and diagnostics. Therefore the preparation of high‐purity In‐111 solutions from irradiated targets is of great interest. In‐111 can be produced by a large number of nuclear reactions, e.g. from cadmium targets, preferably from enriched Cd‐112 targets, by irradiation with protons or deuterons. Reliable methods for preparing In‐111 radioisotope solutions of high radiochemical and chemical purity are thus needed. This work illustrates a fast and convenient way for further purification of 111In solutions shortly before their use. Elution studies have been undertaken to examine the behavior of cadmium and indium isotopes on four commercially available SPE materials—TRU Resin®, Ln Resin®, and Ac Resin®—all of which are manufactured by Eichrom Technologies, Inc. These resins were found to be best suited for 111In separation. Reaching high yields of 111In with high chemical purity, i.e., very low concentration of unwanted elements (preferably below the limit of detection <10−8).

Effects of Diet Intakes on Metal and Electrolyte Distributions in Vital Organs

The intake and concentration of metals and electrolytes from our diet are believed to be affecting our general health, in particular, the proper functions of vital organs. For example, in addition to other genetic and environmental factors, consuming water with high alkalinity for prolonged time is suspected to lead to diseases such as kidney stone. Evidence has been accumulating that excessive metal intakes would lead to organ failures. Once absorbed, minerals and electrolytes can travel freely throughout the body, and distribute at key organ systems such as the brain, lung, kidney, etc. By conducting experiments with animal models (e.g., rats), it is possible to not only determine where the organ distribution of various matrices of elements and minerals but also correlate such matrices with the overall physiological and behavioral status of such models. In this study, information matrices of 30 different elements (including heavy metals and some electrolytes) and their distributions in various vital organs (e.g., brain, lung, kidney, liver, heart, spleen, and uterus) were analyzed as a function of normal dietary intake at adulthood (120 days old). An elemental (metal and electrolyte) distribution model was then formulated based on experimental results. The study has high impact to our understanding of how environmental health would affect our well being. This study would also provide insights on how our diet would affect the accumulations of unwanted elements, such as heavy metals, in our vital organs. The results may help researchers and health practitioner to identify possible links between daily diet (metals and electrolytes) and diseases, and may also lead to a better understanding of diseases associated with aging such as Alzheimer's and Parkinson's diseases, and other neurological disorders.

Street Vendors as ‘Out of Place’ Urban Elements

The existence of street vendors has become a problematic issue in many countries. Despite various arguments that either support or reject their presence in urban environments, street vendors generally have been accused of disrupting the order of the environment and therefore should be removed. The arguments in this paper reconsider the position of street vendors in Indonesian cities, drawing on Mary Douglas' theory of ‘out of place’. Such a reassessment of street vendors as the ‘out of place’ urban elements offers a theoretical basis for the practice of urban design and planning in dealing with certain unwanted elements.