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As the bandwidth of data center switches increases, a disproportionate amount of power is becoming dedicated to the switch - optics interface. Reducing the physical separation between these two components by co-packaging enables system power savings which is essential to continued bandwidth scaling.

In current research guidelines, much focus is placed on ethical management of animals and the application of principles of reduction, refinement and replacement. Of these refinements through environmental enrichment is an important aspect when housing primate to prevent behavioural problems. In this study, we investigated the co-housing of domestic cats and vervet monkeys as a novel method of enrichment based on the cohabitation and stress alleviation effect of horses housed with goats and from seeing cats cohabitating with vervet monkeys in an animal sanctuary. The study used a habituation method whereby the cats were stepwise introduced to the monkeys by sight and smell but with physical separation. Assessment included changes in behaviour, weight and faecal glucocorticoid metabolite (fGCM) concentrations over time. On the first day of housing, the vervets whilst inquisitive kept their distance. The vervets housed in cages that were closest to the cats were the most active and during the first minute of introduction made more alarm calls, which stopped a few days later. The fGCMs were non-significantly different. The results of this study provide evidence that vervet monkeys and domestic cats could potentially be housed together without overt aggression. We thus suggest further observations to ascertain if the co-housing could have long-term benefits for vervet monkeys, from the companionship that would be offered by the cats.

Education is one of the most essential universal rights, therefore it is necessary to guarantee its accessibility to the entire population and especially to the most disadvantaged areas. This study analyzes the physical proximity of the population to the public education system, seen from the perspective of pedestrian displacement, for which quantitative variables (conditions of displacement, recruitment of students) and qualitative variables (social characteristics of the population) were contrasted. In the first part, it was possible to clarify that the state educational offer in Sincelejo exhibits a spatial pattern of random distribution in all levels of education, while in the second part it was possible to show that the distance (spatial separation) and the time used to travel towards educational facilities, it is given according to the spatial arrangement of each establishment and the road articulation of Sincelejo. The analysis showed that the level of general physical access to public educational institutions is favorable, with an average time of 11.8 minutes, hence communes two, four, eight, and one present the best conditions as they are below the average, in On the other hand, in the areas where cohesion and road infrastructure present deficiencies, the members of the student community can see the increase in travel times to 12.6 15 and 24.6 minutes in communes 9, 6 and 7 respectively. Keywords: public education, spatial justice, physical separation, GIS. Resumen .......................................................................................................................................... 4 Summary ......................................................................................................................................... 5 1. Introducción ............................................................................................................................... 6 2. Área de estudio ....................................................................................................................... 9 3. Materiales y métodos ........................................................................................................... 11 3.1. Procesamiento de la información ............................................................................ 13 4. Análisis de resultados .......................................................................................................... 15 4.1. Análisis de distribución y accesibilidad espacial al equipamiento educativo más cercano en el área urbana de Sincelejo durante el año 2019. ................................................................... 15 4.2. Accesibilidad promedio a equipamientos educativos de nivel preescolar y básica primaria. ....................................................................................................................................................................... 18 4.3. Accesibilidad promedio a equipamientos educativos de nivel básica secundaria y media académica. ................................................................................................................................. 21 4.4. Accesibilidad promedio a equipamientos educativos de ciclo completo. ...................... 23 4.5. Proximidad promedio a equipamientos de educación en Sincelejo. .............................. 26 5. Discusión ............................................................................................................................... 28 6. Conclusión ............................................................................................................................. 31 7. Referencias bibliográficas ..................................................................................................... 33 Monografía La educación supone uno de los derechos universales más esenciales, por ello es necesario que se garantice su accesibilidad a toda la población y en especial a las zonas más desfavorecidas. En este estudio se analiza la proximidad física de la población al sistema de educación pública, visto desde la perspectiva del desplazamiento peatonal, para lo cual fueron contrastadas variables cuantitativas (condiciones de desplazamiento, captación de estudiantes) y cualitativas (características sociales de la población). En la primera parte se logró esclarecer que la oferta educativa estatal en Sincelejo exhibe un patrón espacial de distribución aleatorio en todos los niveles de educación, mientras que en la segunda parte se logró evidenciar que la distancia (separación espacial) y el tiempo empleado para desplazarse hacia los equipamientos educativos, se da en función de la disposición espacial de cada establecimiento y la articulación vial de Sincelejo. El análisis demostró que el nivel de acceso físico general a instituciones educativas públicas es favorable, con un tiempo promedio de 11,8 minutos, de ahí que las comunas dos, cuatro ocho y uno presenten las mejores condiciones al estar por debajo del promedio, en cambio, en las zonas donde la cohesión e infraestructura vial presentan deficiencias los miembros de la comunidad estudiantil pueden ver el aumento en los tiempos de desplazamiento a 12,6 15 y 24,6 minutos en las comunas 9, 6 y 7 respectivamente. Pregrado Geógrafo(a)

In quantum physics, quantum entanglement is a phenomenon that occurs when a group of particles is generated in such a way that the quantum state of each individual particle cannot be described independently from the other. The work Glass Entanglement constructs a similar state in which neither its digital nor analog parts could be read individually and where each part could not be described independently from the other. This work consists of the physical separation of the parts of cellular glass volumes from one another and the 3D-printed form interacting with these single objects to form an ecosystem between the glass volumes. The elements are held together by digitally modeled, tendril-like structures, analogous to the biological cell growth when forming multicellular higher-order organisms.

Though not a new term, “social distancing” exploded onto the global stage as an expression to publicize the only means currently available to control the transmission of COVID-19. This term is increasingly being adopted and translated into the vernacular to inform and guide public behavior in most, if not all, countries around the world. However, any effective global response requires direct and unambiguous communication and sharing of ideas across communities with different cultural backgrounds as well as between researchers and responders across the disciplinary spectrum. Unfortunately, social distancing is a misnomer. The current use of social distancing – separating ourselves physically to avoid infection – is not consistent with what the term actually means. Consequently, as a diktat, social distancing is not self-explanatory, conceptually ambiguous, practically misleading, and intellectually misplaced. To highlight these problems, we present arguments from multiple perspectives, calling governments, public health officials, and the media to abandon the use of social distancing, replacing it with more intuitively accurate and meaningful terms. Such a move would ensure clear consistent messaging that is critical to retain public trust especially during global public health crises.

Deconvolution of forensic DNA mixtures into their individual component DNA (geno)types is of great investigative value, though often complex and difficult. Two-person mixtures comprising a major and minor contributor are often easily interpreted although, when the DNA ratio of the two individuals is approximately equal (~1:1), deconvolution and interpretation becomes much more difficult. To address this issue, a physical separation of individual-, two- or three- cell subsamples prior to autosomal STR analysis was performed using a simplified micromanipulation technique paired with a decreased reaction volume and increased cycle number PCR. Using this method, single and multiple buccal epithelial cells were collected from a 1:1 two-person mixture (i.e. from individual 'A' and 'B') and directly amplified, omitting standard DNA extraction and purification steps. Single cell subsamples resulted in partial single-source profiles for both contributors while, in accordance with expectations of a quasi-binomial sampling schema, two- and three-cell subsamples resulted in single source informative partial profiles of individual A and individual B as well as complete consensus profiles, and equally mixed 1:1 (2-cell subsamples) and 2:1 (3-cell subsamples) admixed profiles of individual A and B.This proof-of-concept approach shows promise in permitting the DNA deconvolution of mixed samples where the individual contributors are present in similar amounts that would otherwise be difficult to interpret, resulting in an increase in evidentiary value. The subsampling approach can be readily investigated for DNA casework applications without additional investment in costly, new equipment, requiring only a stereo microscope and a tungsten needle.

Binary quasars are extremely rare objects, used to investigate clustering on very small scales at different redshifts. The cases where the two quasar components are gravitationally bound, known as physical binary quasars, can also exhibit enhanced astrophysical activity and therefore are of particular scientific interest. Here we present the serendipitous discovery of a physical pair of quasars with an angular separation of $\Delta\theta = (8.76 \pm 0.11)$ arcsec. The redshifts of the two quasars are consistent within the errors and measured as $z = (1.76\pm 0.01)$. Under the motivated assumption that the pair does not arise from a single gravitationally lensed quasar, the resulting projected physical separation was estimated as $(76 \pm 1)$ kpc. For both targets we detected Si VI, C VI, C III], and Mg II emission lines. However, the two quasars show significantly different optical colours, one being among the most reddened quasars at $z > 1.5$ and the other with colours consistent with typical quasar colours at the same redshift. Therefore it is ruled out that the sources are a lensed system. This is our second serendipitous discovery of a pair of two quasars with different colours, having a separation $\lesssim 10$ arcsec, which extends the very limited catalogue of known quasar pairs. We ultimately argue that the number of binary quasars may have been significantly underestimated in previous photometric surveys, due to the bias arising from paired quasars with very different colours.

Recovering indium from liquid crystal display (LCD) screen waste is important from a sustainability point of view for several reasons: the environmentally hazardous metals are not landfilled, the recovery process involves lower CO2 emissions than primary production, and supply from secondary sources matches the continuously increasing demand of indium. In this study, two alternative process routes for recycling the critical metal, indium, from LCD panel waste were studied and compared using laboratory and bench-scale experiments. The first process was a conventional hydrometallurgical process that involves manual dismantling, hammer mill crushing of the glass, cross-current sulfuric acid leaching of the metals, and liquid-liquid extraction separation of indium. Using this process, over 99% pure indium solution can be produced with a recovery yield of over 70%. The second process is novel because it includes (manual) scraping of the indium tin oxide (ITO) layer from the glass panels, followed by sulfuric acid leaching of the metals. The yield of indium was over 80%, and the purity of the resulting solution was over 99%. The solutions obtained from either of the suggested processes were sufficiently pure for cementing indium in high purity. The novel process appears much more straightforward and economically more feasible because the polarizing filter need not be removed and the liquid-liquid extraction purification step is excluded. Moreover, less amount of leaching acid is required. Post-print / Final draft

International audience; This paper offers new evidence on the residential arrangements of couples in the context of migration and urbanisation in Africa, focusing on the case of Ouagadougou, Burkina Faso's capital city. We use a mixed-methods approach, combining data from a survey on the family histories of migrants merged with data from the Ouagadougou Health and Demographic Surveillance System and qualitative interviews. The objective is to analyse how the migrants themselves perceive "living apart together", the extent of this phenomenon, its timing, and the factors influencing it. The longitudinal nature of our data specifically allows for the study of the drivers of couple reunification in Ouagadougou and of the physical separation of partners, whereby one goes to live away from Ouagadougou. Our results reveal that 25% of migrants in a union had a partner living outside Ouagadougou in 2015, and that the residential arrangements of such couples were associated with gender relations, family cycle, and integration into the city.

‘Whenever I write to you, I seem to be transported to your presence’: the remarks that open Leigh Hunt’s 23 August 1819 letter to the Shelleys exhibit, in miniature, the characteristics that define Hunt’s epistolary style. If Hunt is a writer who delights in the bonds that might be established or maintained through the letter, his letters remain conscious of the physical experiences and encounters that cannot be replicated easily within the scope of the epistolary form. In the above quotation, the conditional ‘seem’ casts a qualifying shadow over Hunt’s celebration of an imagined proximity, even as the letter prizes this state of seeming as a means of converting absence into a virtual form of presence, however temporary this illusion may be. Such ambivalence is typical of Hunt’s letters to the Shelleys, which exemplify Hunt’s use of the letter as a means of negotiating divisions between himself and his correspondents, as well as Hunt’s understanding of the letter as a vehicle of mobility, a space in which a writer must adopt varying postures and positions depending on the needs of his correspondent and the communicative situation. Having first met in 1811, Hunt and Shelley forged a friendship in 1816 that remained close until Shelley’s death in 1822, including the years from 1818 onwards when Shelley, with Mary, was resident in Italy. Their separation shaped a correspondence that involved Marianne Hunt and Mary Shelley as active participants (though Marianne wrote less frequently than Shelley, Mary, or Hunt), with letters often centring on the enduring quality of the two couples’ friendship and the possibility of the Hunts joining the Shelleys in Italy, a reunion belatedly achieved just weeks prior to Shelley’s death. Focusing on letters exchanged by Hunt and the Shelleys in 1819, including those written while Shelley was composing works such as The Mask of Anarchy late that year, this essay will explore the varying ways Hunt’s letters attempt to conjure into being a sense of proximity, connection, or consensus that might reconcile, or at least mitigate, divisions ranging from physical separation to ideological discord.

Screening is a process of continuous physical separation of two or more powdered material depending on the particle size and particle shape. The present investigation involves the study of screening efficiency obtained in the widely used plant scale linear vibrating screen. The present investigation also involves the recommendations for improving screening efficiency. The result shows that the linear vibrating screen has the maximum screening efficiency of 65.92% for first 10 minutes of screening and reduced up to 59.34% for 60 minutes of screening. The reduction in screening efficiency with respect to screening time is due to the screen blinding. The screening of powdered materials faces the problem of screen mesh blinding which reduces the screening efficiency. The present authors recommend utilizing the screen configuration of circular vibrating screen which can provide higher screening efficiency with reduced screen blinding. The utilization of circular vibrating screen will reduce the screen blinding and prevents the labor requirement for removing screen blinding thereby increasing the efficiency and the production rate of screening.

It is well-known that energy-rich radiation induces water splitting, eventually yielding hydrogen peroxide. Synthetic applications, however, are scarce and to the best of our knowledge, the combination of radioactivity with enzyme-catalysis has not been considered yet. Peroxygenases utilize H2O2 as an oxidant to promote highly selective oxyfunctionalization reactions but are also irreversibly inactivated in the presence of too high H2O2 concentrations. Therefore, there is a need for efficient in situ H2O2 generation methods. Here, we show that radiolytic water splitting can be used to promote specific biocatalytic oxyfunctionalization reactions. Parameters influencing the efficiency of the reaction and current limitations are shown. Particularly, oxidative inactivation of the biocatalyst by hydroxyl radicals influences the robustness of the overall reaction. Radical scavengers can alleviate this issue, but eventually, physical separation of the enzymes from the ionizing radiation will be necessary to achieve robust reaction schemes. We demonstrate that nuclear waste can also be used to drive selective, peroxygenase-catalyzed oxyfunctionalization reactions, challenging our view on nuclear waste in terms of sustainability.

The successful use of physical separation via adsorption for the removal of contaminants of emerging concern (CECs) from water ultimately will depend on the ability of designing the adsorbent from the bottom up to tailor its textural properties and surface functional groups to simultaneously target both the physical and chemical identities of the contaminants. In this chapter, we present and discuss various efforts made in this area for particular families of adsorbent materials, namely carbon-based zeolites, metal–organic frameworks, mesoporous silica, clays, and composites. Functionalization of these materials in attempts to enhance surface area, pore volume, and surface charging, as well as imparting combined hydrophobicity and specific surface interactions (other than electrostatic), and how these affect both CEC adsorption capacity and selectivity are thoroughly discussed.

We present 10 new ultracool dwarfs in seven wide binary systems discovered using Gaia second data release data, identified as part of our Gaia Ultra-Cool Dwarf Sample project. The seven systems presented here include an L1 companion to the G5 IV star HD 164507, an L1: Companion to the V478 Lyr AB system, an L2 companion to the metal-poor K5 V star CD-28 8692, an M9 V companion to the young variable K0 V star LT UMa, and three low-mass binaries consisting of late Ms and early Ls. The HD 164507, CD-28 8692, V478 Lyr, and LT UMa systems are particularly important benchmarks, because the primaries are well characterized and offer excellent constraints on the atmospheric parameters and ages of the companions. We find that the M8 V star 2MASS J23253550+4608163 is ∼2.5 mag overluminous compared to M dwarfs of similar spectral type, but at the same time it does not exhibit obvious peculiarities in its near-infrared spectrum. Its overluminosity cannot be explained by unresolved binarity alone. Finally, we present an L1+L2 system with a projected physical separation of 959 au, making this the widest L + L binary currently known., With funding from the Spanish government through the "María de Maeztu Unit of Excellence" accreditation (MDM-2017-0737)

The cumulative work of several decades of cancer research has unveiled a wealth of genotypic and phenotypic profiles on many types of cancer and associated biomarkers. While therapies and diagnostics targeting specific protein-based biomarkers have demonstrated enormous success, there are many biomarkers left to discover and evaluate for efficacy. Lipids play a significant role in the manifestation of cancer. However, research into lipid biomarkers of cancer is still in its infancy, as methods for isolating and characterizing lipids still predominantly rely on physical separation techniques and spectroscopic evaluation. Disease biomarkers often have hydrophobic and hydrophilic moieties required for biological function. Yet, most detection methods target the hydrophilic proteomic or glycosylated components, and ignore the relevance of lipids in disease manifestation. Recent advances in lipid-based detection technologies coupled with continued development of antibodies against small, lipidic molecules may serve as key factors for unlocking the future of lipid-based cancer diagnostics.

Quantitative understanding of transmission with and without control measures is important for the control of infectious diseases because it helps to determine which of these measures (or combinations thereof) will be effective to reduce transmission. In this paper, the statistical methods used to estimate transmission parameters are explained. To show how these methods can be used we reviewed literature for papers describing foot-and-mouth disease virus (FMDV) transmission in pigs and we used the data to estimate transmission parameters. The analysis showed that FMDV transmits very well when pigs have direct contact. Transmission, however, is reduced when a physical barrier separates infected and susceptible non-vaccinated pigs. Vaccination of pigs can prevent infection when virus is administered by a single intradermal virus injection in the bulb of the heel, but it cannot prevent infection when pigs are directly exposed to either non-vaccinated or vaccinated FMDV infected pigs. Physical separation combined with vaccination is observed to block transmission. Vaccination and separation can make a significant difference in the estimated number of new infections per day. Experimental transmission studies show that the combined effect of vaccination and physical separation can significantly reduce transmission (R < 1), which is a very relevant result for the control of between-farm transmission.

Efficient mitigation of toxic and recalcitrant heavy metal complexes (HMCs) from water and wastewater is critical to guarantee the environmental health and safety, but still faces many challenges. Although a number of techniques have been developed to deal with HMCs laden water/wastewater, there is still a lack of comprehensive and insightful understanding of the relevant mechanisms. One of the main reasons is the complicated heavy metal speciation in water/wastewater, which masks the speciation distribution and coordination circumstance of heavy metals. In this review, prevalent methods for HMC elimination (e.g., physical separation and chemical decomplexation) are briefly presented and evaluated. Especially, the characterization methods of HMCs, which afford to provide valuable information on the speciation distribution of heavy metals, are underlined and discussed. Furthermore, typical cases are provided to elucidate the essential role of species transformation in the decomplexation of HMCs and the implications for enhanced mitigation of HMCs are also discussed. Finally, the current challenges and perspectives for future study in this field are proposed.

Eramet uses a combination of physical and hydrometallurgical treatment to recycle lithium-ion batteries. Before hydrometallurgical processing, mechanical treatment is applied to recover the Black Mass which contains nickel, cobalt, manganese and lithium as valuable elements as well as graphite, solvent, plastics, aluminium and copper. To evaluate the suitability for hydrometallurgical recycling, it is essential to analyse the Black Mass chemically but also with respect to size, shape and composition of particles in the Black Mass. The Black Mass of various battery recyclers was investigated by using a combination of SEM/QEMSCAN® analyses. This specific QEMSCAN® database contains 260 subgroups, which comprise major and minor chemical variations of phases. The database was created using millions of point analyses. Major observations are: (1) particles can be micro-texturally characterised and classified with respect to chemical element contents; (2) important textural and chemical particle variations exist in the Black Mass from several origins leading to different levels of quality; (3) elements deleterious to hydrometallurgical processing (i.g. Si, Ca, Ti, Al, Cu and others) are present in well liberated particles; (4) components can be quantified and cathodes active material compositions (LCO, different NMC, NCA, LFP, etc.) that are specific for each battery type can be identified; (5) simulation of further physical mineral processing can optimise Black Mass purity in valuable elements.

Only when problems in ultrafine coal particle beneficiation process are well understood and clarified, efficient methods can be devised to recover ultrafine coal particles in an economically viable way. When minerals are fully liberated from organic substances in the grinding process, coal beneficiation methods are needed to efficiently separate organic materials from mineral ones. This is necessary for clean coal technologies as the pollutants associated with coal utilization are the key factor in limiting the sustainability of coal utilization. To assess the current state of knowledge available in this area, a comprehensive literature review on the ultrafine coal particle beneficiation techniques is carried out with main focus on recent progresses. In this paper, previous studies on the ultrafine coal beneficiation have been critically analyzed with respect to the effects of particle sizes and surface properties. The techniques are classified into two categories, physical separation (including gravity, magnetic and electrostatic separation method) and physico-chemical separation (including oil agglomeration and bubble flotation method). The aim of this paper is to review developments and limitations of current ultrafine coal particle beneficiation techniques and also to identify the future development in recovering ultrafine coal particles.

The struggle between the bourgeoisie and the working class is reflected in the filmography of many countries, including that of Spain and Argentina, specifically through the films El Ángel Exterminador (The Exterminating Angel) (1962), directed by Luis Buñuel, and La Ciénaga (The Swamp) (2001), directed by Lucrecia Martel. Each director utilizes interior and exterior space to demonstrate the difference between the working and bourgeoise classes within their films. As stated by Charles Shiro Tashiro in his observations of The Go-Between, the set design and narrative of cinema are intertwined in such a way that the setting of a film is essential to the successful delivery of the message and context of said film. This comparative study will focus on how Buñuel’s and Martel’s aforementioned films follow a similar pattern in 3 aspects of this use of space: the use of large estates with the mansion in The Exterminating Angel and the La Madrágona house in The Swamp to create a physical barrier that is representative of the metaphorical barrier between socioeconomic classes, the use of interior space to create a sense of entrapment within the confines of the bourgeoisie, and the sense of barrenness created by the grandeur of the bourgeois space.

This article applies the concept of ritual to cybersecurity expertise, beginning with the cybersecurity “skills gap”: the perceived lack of suitably qualified professionals necessary to tackle contemporary cybersecurity challenges. It proposes that cybersecurity expertise is best understood as a skilled performance which satisfies decision-makers’ demands for risk management. This alternative understanding of cybersecurity expertise enables investigation of the types of performance involved in key events which congregate experts together: cybersecurity conferences. The article makes two key claims, which are empirically based on participant observation of cybersecurity conferences in the Middle East. First, that cybersecurity conferences are ritualized activities which create an expert community across international boundaries despite significant political and social differences. Second, that the ritualized physical separation between disinterested knowledge-sharing and commercial advertisement at these conferences enacts an ideal of “pure” cybersecurity expertise rarely encountered elsewhere, without which the claims to knowledge made by cybersecurity experts would be greatly undermined. The approach taken in this article is thus a new direction for cybersecurity research, with significant implications for other areas of international politics.

Current available models for simulation of the separation process in gas-liquid membrane contactor (MC) systems consider a uniform partial membrane wetting along the membrane length ( L mem ) . However, transmembrane pressure changes along the L mem . Additionally, the available models usually consider a simplified uniform pore size to represent the micro-porous MC. Additionally, not all pores in a MC have the same size. In this study, a pore-scale network model is developed to simulate the physical separation of H2S using MCs by taking to account for (i) transmembrane pressure variation and (ii) pore size distribution of MC. The model results are compared with the experimental results of H2S separation. Modeling results indicate that membrane wetting is non-uniformly distributed along L mem . The membrane wetting ratio is maximum at the inlet of the liquid phase, and it decreases toward the liquid outlet. Also, increasing the inlet gas pressure reduces the membrane wetting ratio, and leads to higher H2S separation. Moreover, the model results indicate that shifting of the pore size distribution of MC towards smaller pore size declines the membrane wetting ratio and increases the H2S separation efficiency.

The road median is a physical separation of the traffic lane that serves to eliminate traffic conflictsfrom the opposite direction, which in turn will improve the safety of traffic. road infrastructure factorsthat do not meet safety standards. An example is due to the manufacture of a median road at eachintersection that does not meet such standards as too wide and too high such as in the tegal city ofDiponegoro, this indicates reduced main function of the median road, Antrhopometry is anapproximation of the size of the human body. In this study discusses how to make the mediandesign does not eliminate the main function of traffic separator traffic by using antrhopometry. Thedata used are high-dimensional data of sight and median dimension size, looking forstandardeviation as the lowest value of high vision value to find the right value as a redesignracetrack.

It is widely recognized that a father’s incarceration strains a family, but too little is known about preincarceration family life, how families divided by incarceration navigate the imprisonment, and what they expect for postrelease family life. We analyze data from 1,482 incarcerated men and their partners to examine the assets and challenges that families brought with them into the incarceration experience; their considerable efforts to maintain family life during an incarceration in the face of physical separation and other obstacles; and the areas of convergence and divergence in their expectations for family life after the male partner’s release.

The article makes an effort in consolidating the developments in the field of advanced gravity separation techniques for processing fine particles over the last few decades. The application potentials of various unit operations and the influence of process variables and feed characteristics on the process performance are identified. Fundamentals of advanced gravity separators are discussed from theoretical and applied perspectives. Comparative analyses of various related unit operations are incorporated including the advantages and short falls of different advanced gravity separation techniques. A general guideline is presented that will help designing new mineral processing flow sheets with better efficiency indices.

Many routine relationship maintenance activities, such as supporting each other in the household, rely on responsive interaction. Unfortunately, the physical separation typical for long-distance re...

Geopolymers are alternative materials to portland cement, obtained by alkaline activation of aluminosilicates. They exhibit excellent properties and a wide range of potential applications in the field of civil engineering. Several natural aluminosilicates and industrial by-products can be used for geopolymer synthesis, but a lot of starting materials have the disadvantage of poor reactivity and low strength development. This paper presents a comprehensive review of the main methods used to alter the reactivity of aluminosilicate materials for geopolymer synthesis, as reported recently in the literature. The methods consist of mechanical, thermal, physical separation and chemical activation, of which mechanical activation is the most commonly employed technique. The reactivity of the activated aluminosilicate materials is mainly related to the activation method and the treatment parameters. Chemical activation by alkaline fusion is a promising method allowing preparation of one-part geopolymer materials, an alternative class of geopolymeric binders. However, the resulting alkaline-fused geopolymer products are vulnerable to attack by excessive alkalis.

Printed circuit boards (PCBs) are difficult to recycle because of the layered structure of non-metal (i.e., epoxy resin, glass fiber) and copper. In this work, we conducted a systematic investigation to effectively recover copper from PCB. A thermal treatment was employed for improving the crushing performance of PCB and conducted by varying the temperature and the gas. Then, the mechanical strength, degree of liberation (DL), and copper separation efficiency of the heat-treated and untreated PCBs were investigated. After heat treatment under a 300 °C air atmosphere, the mechanical strength of PCB decreased from 386.36 to 24.26 MPa, and copper liberation improved from 9.3% to 100% in the size range of a coarser size fraction (&gt, 1400 μm). Accordingly, when electrostatic separations were performed under these conditions, a high-Cu-grade concentrate and high recovery could be obtained. The results show that the change in the physical properties of the PCBs leads to an improvement in the DL following thermal decomposition at 300 °C in air. Our study elucidates the physical properties of PCBs and the DL under various heat treatment conditions. Furthermore, it shows that the heat treatment condition of 300 °C in air is ideal for recovering copper from the PCB.

Skid resistance of roads enables drivers to shorten their stopping distances and to follow their desired trajectories on curves, too. The road texture remains the principal parameter governing skid resistance, especially in wet conditions. That texture is composed of a multitude of wavelengths with the microtexture and macrotexture considered to be the most important vis-a-vis to skid resistance. The present work contributes to the numerous analyses of the role of these two texture scales, as many authors have done before. It is based on the physical separation of these two scales of textures using an empirical mode decomposition and systematic identification of their roles on skid resistance using a dynamic friction model. The results found in this present work consolidate well the findings of previous works. Indeed, they show that the higher the microtexture is, the better the skid resistance will be at low speeds. Furthermore, the higher macrotexture is, the better the skid resistance is at high speed. These results have led to the proposal of algebraic relations linking skid resistance to microtexture and macrotexture at all speeds, constituting then a clear step forward compared to previous works.

Le socle du Sud Maradi (Sud Niger) correspond à l’extrémité Nord du bouclier Bénino-Nigérian, appartenant à la zone mobile panafricaine à l’Est du Craton Ouest-Africain. Cette étude apporte une modeste contribution dans la caractérisation géochimique des minéralisations aurifères de cette province métallogénique panafricaine. A cet effet, l’approche méthodologique mise en oeuvre associe le dosage géochimique de l’or par absorption atomique (Au Fire Assay/AA) pour les roches saines, et la séparation des pépites d’or par l’utilisation de la table à secousse pour les altérites du socle et les sédiments (placers et paléoplacers). Les analyses géochimiques ont mis en évidence l’existence de deux types de minéralisations: primaires et secondaires. Les minéralisations primaires de l’or sont à l’état disséminé (faibles teneurs de 0.005 à 0.017 g/t) mais des teneurs relativement plus élevées (0.006 à 0.017 g/t) ont été enregistrées au voisinage des zones de cisaillement du socle. Tandis que la minéralisation secondaire, mise en évidence dans les altérites du socle, dans les alluvions (placers) et dans les grès du Crétacé (paléoplacers) présentent des teneurs en or plus élevées (5 à 30 g/t), dépassant largement les teneurs des minéralisations primaires observées dans les roches saines du socle. Ce grand écart de teneurs s’explique par un fort lessivage du socle, qui aurait permis une reconcentration de l’or dans les sédiments. The South Maradi (South Niger) basement corresponds to the northeastern part of the Benin-Nigerian Shield, belonging to the Pan-African mobile zone, which is located to the east of the West African Craton. This study brings a modest contribution to the geochemical characterization of gold mineralization in this Pan-African metallogenic province. For this purpose, the methodological approach implemented combines the geochemical determination of gold contents by atomic absorption (Au Fire Assay/AA) for basement rocks and physical separation of gold specks by using the vibrating table process for basement alterites and sediments (placers and paleoplacers). The obtained results showed two types of gold mineralization: primary and secondary. Primary gold mineralization is in a disseminated state (low contents of 0.005 to 0.017 g / t) but relatively the higher values (0.006 to 0.017 g / t) were recorded near the basement shear zones. While the secondary gold mineralization, highlighted in basement alterites, alluvium (placers) and Cretaceous sandstones (paleoplacers) present higher gold contents (5 to 30 g / t) than primary gold contents observed in basement rocks. This large difference in values can be explained by a strong alteration of the basement, which would have allowed a reconcentration of the gold in the sediments.