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In the present study, indigo blue dye removal efficiency of activated carbon (AC) and natural clay (NC) was evaluated and compared, firstly in an adsorption unit, and then in an adsorption coupling ultrafiltration (A/UF) system. Effect of operating variables like pH, contact time, adsorbent dosage, initial dyes concentration during the adsorption was investigated and consequently optimised. The optimal conditions were employed for the adsorbents during the removal of the dye in the A/UF system. The optimal amount of NC and AC was 0.4 g/L and 0.3 g/L, respectively, and NC and AC displayed adsorption capacity of 57 mg/g and 53 mg/g, respectively, at this condition. Application of UF reveals a decrease of membrane fouling for both adsorbents in A/UF system. In addition, colour retention, when the adsorbents were used in A/UF, increased significantly from 90.5% to 99% as compared to using adsorption only. The efficiency of the membrane regeneration was estimated by the determination of the water permeability after rinsing. It is noteworthy to mention that a total regeneration of the membrane after the application of continous hybrid A/UF was achieved, however, the use of UF alone exhibited a fouling decrease by 40%. [ABSTRACT FROM AUTHOR]

In the present work, two Algerian clay samples, Djebel Debagh (DD3) and Tamazert (KT2), were used as adsorbents for the removal from the water of Derma Blue R67, which is an acid dye commonly used in the tanning industry. The two clay samples used were first treated by acid in order to enhance their retention capacities, and then characterized using X-ray diffraction, scanning electron microscopy, surface area measurements (Brunauer, Emmett et Teller method (BET)), surface charge (points of zero net proton charge), and electrophoretic mobility (Zetaphoremeter). Further, the adsorption experiments of the acid dye from water onto the clay surface were carried out by investigating various parameters such as, the contact time, the initial dye concentration, the aqueous phase pH, the clay amount and the temperature. The results indicate that the two adsorbents are efficient and that the anionic dye removal from water is mainly feasible at ambient temperature. Further, the comparison of the experimental adsorption data to the prediction models has shown that the Langmuir model gives the best fit, indicating the formation of a monolayer by the acid dye molecules on the clay surface. Finally, the adsorption kinetics follows a two-type process onto KT2 kaolinite, whereas onto DD3, it only follows the pseudo-second order model. From the overall data, it is concluded that the Algerian local kaolin clays are good adsorbent candidates for wastewater treatments [ABSTRACT FROM AUTHOR]

A significant amount of unused dyes remain in textile industry wastewater, the treatment of which presents a great challenge, particularly in semi-arid countries where water resources are of great concern. Liquid-phase adsorption is highly efficient for the removal of dyes and adsorbents, for example, activated carbons are used to treat wastewater, but are expensive. Clays are cheaper and several works have showed their high pollutant adsorption capacity in cases of environmental problems. The aim of this work is to present the use of clay as a means of textile wastewater treatment and colour adsorption. The adsorbent used in this study is natural clay from the Fouchana region (Tunisia), which contains 60% smectites, 30% kaolinite and 10% illite, in which the cation-exchange capacity is about 50 meq/100 g of clay. Two types of waters were treated: one from a leaching textile industry and another from a dyeing industry. Moreover the treatment by clay was compared to the treatment by a coagulation flocculation standard method. The experimental results show that the treatment by natural clay is more efficient than the conventional treatment by coagulation flocculation. It allowed decolorization of the dye effluent and a decrease down to 97% for biochemical demand for oxygen, 93% for suspended matter, 95% for chemical demand for oxygen and 76% for the spectral absorption coefficient. Thus, the quality of dye wastewater has reached the Tunisian standards of releases (NT 106.02 and 106.03, 1989), and as such it makes it possible to test wastewater at the industrial scale. [ABSTRACT FROM AUTHOR]

Nador lagoon sediments (East Morocco) are contaminated by industrial iron mine tailings, urban dumps and untreated wastewaters from surrounding cities. The lagoon is an ecosystem of biological, scientific and socio-economic interests but its balance is threatened by pollution already marked by biodiversity changes and a modification of foraminifera and ostracods shell structures. The aim of the study is to assess the heavy metal contamination level and mobility by identifying the trapping phases. The study includes analyses by ICP-AES and ICP-MS, of, respectively, major (Si, Al, Mg, Ca, Fe, Mn, Ti, Na, K, P) and trace elements (Sr, Ba, V, Ni, Co, Cr, Zn, Cu, As, Pb, Cd) in sediments and suspended matter, heavy metals enrichment factors calculations and sequential extractions. Results show that sediments contain Zn, Cu, Pb, V, Cr, Co, As, Ni with minimum and maximum concentrations, respectively, of 4–1190 μg/g, 4–466 μg/g, 11–297 μg/g, 11–194 μg/g, 9–139 μg/g, 1–120 μg/g, 4–76 μg/g, 2–62 μg/g. High concentrations in Zn are also present in suspended matter. The enrichment factors show contamination in Zn, Pb and As firstly induced by the mining industry and secondly by unauthorized dumps and untreated wastewaters. Cr and Ni are bound to clays, whereas V, Co, Cu and Zn are related to oxides. Thus, the risk in metal mobility is for the latter elements and lies in the oxidation–reduction-changing conditions of sediments. [ABSTRACT FROM AUTHOR]

Abstract: One of the principal applications for bentonite is in drilling muds. Moreover it is widely used as a suspending and stabilizing agent, and as an adsorbent or clarifying agent, in many industries. Recently the bentonites have been proposed as engineered barriers for radioactive waste repository because these materials are supposed to build up a better impermeable zone around wastes by swelling. For these reasons, a textural characterization of bentonites in the laboratory is very important. The aim in this study was to estimate several textural properties of compacted and cation-exchanged bentonite by using Hg-porosimetry, N2-adsorption, water vapour adsorption, scanning electron microscopy (SEM) observations and environmental scanning electron microscopy-digital images analysis measurements. For that, bulk samples were mechanically compressed at atmospheric conditions by using a uniaxial system at four different pressures (21, 35, 49, and 63MPa) in order to obtain four physical densities. On the other hand, the bulk samples of bentonite were treated separately with four concentrated solutions (1N concentration) of sodium, potassium, magnesium and calcium chlorides in order to obtain a homoionic interlayer cation in the clay phase. The results showed that the macro-porosity (porous size>50nm) and eventually the mesoporosity (porous size 2–50nm) are affected by the uniaxial compaction. In this case, a transformation of the shape of the macro-pores network from tube to crack was observed. On the other hand, the swelling potential and water content are governed by the relative humidity and by the nature of interlayer cation. [Copyright &y& Elsevier]

Abstract: Soils of the semi-arid area of the El Melah coastal lagoon (NE Tunisia), with a closing evolution dynamic, were studied aiming: (1) the chemical and mineralogical characterization of surface and subsurface layers of soil profiles from locations previously submerged and of soils developed on dunes; (2) to evaluate the dependence on the environment conditions of the geochemical patterns of the soils; and (3) to determine chemical and mineralogical variations with the emersion of the sediments resulting from the decrease in the extent of the area permanently covered by water in the lagoon. The compositional results obtained showed significant differences depending on the environment (littoral plain, old dunes and sandy spit), but soils of the different environmental zones studied do not appear to be significantly polluted as far as trace elements are concerned. Among the elements studied, high element/Sc ratios and variations were found for As, Sb and Zn. Antimony is more concentrated in coarser samples suggesting its adsorption in Fe or Mn oxides coating quartz grain surfaces. Arsenic and zinc may be incorporated into the carbonates structure, as well as adsorbed on, or coprecipitated with, iron oxides. Zinc may also be significantly incorporated in clay minerals. Iron was found to be more oxidized in the cultivated soil from the old dune strand; and more reduced in the sandy spit where ankerite occurs suggesting the reduction of Fe3+ in oxide/hydroxides by microorganisms and incorporation of Fe2+ in carbonates. REE patterns, particularly the HREE/LREE are correlated with carbonates, indicating preferential incorporation of the HREE in carbonates, and of the LREE in clay minerals/iron oxides. High Ga contents were found in soils and sediments rich in clay minerals/Al, suggesting its incorporation in clay minerals structure. Therefore, Ga may be used as an indicator of the clay minerals proportion in sediments and soils. Carbonates, sulphates, besides Fe and/or Mn oxides and clay minerals, appear to play an important role on the trace elements distribution. [Copyright &y& Elsevier]

A high cost of high-purity materials is one of the major factors that limit the application of ceramic membranes. Consequently, the focus was shifted to using natural and abundant low-cost materials such as zeolite, clay, sand, etc. as alternatives to well-known pure metallic oxides, such as alumina, silica, zirconia and titania, which are usually used for ceramic membrane fabrication. As a contribution to this area, the development and characterization of new low-cost ultrafiltration (UF) membranes made from natural Tunisian kaolin are presented in this work. The asymmetric ceramic membranes were developed via layer-by-layer and slip-casting methods by direct coating on tubular supports previously prepared from sand and zeolite via the extrusion process. Referring to the results, it was found that the UF kaolin top layer is homogenous and exhibits good adhesion to different supports. In addition, the kaolin/sand and kaolin/zeolite membranes present an average pore diameter in the range of 4-17 nm and 28 nm, and water permeability of 491 L/h·m 2 ·bar and 182 L/h·m 2 ·bar, respectively. Both membranes were evaluated in their treatment of electroplating wastewater. This was done by removing oil and heavy metals using a homemade crossflow UF pilot plant operated at a temperature of 60 °C to reduce the viscosity of the effluent, and the transmembrane pressure (TMP) of 1 and 3 bar for kaolin/sand and kaolin/zeolite, respectively. Under these conditions, our membranes exhibit high permeability in the range of 306-336 L/h·m 2 ·bar, an almost total oil and lead retention, a retention up to 96% for chemical oxygen demand (COD), 96% for copper and 94% for zinc. The overall data suggest that the developed kaolin membranes have the potential for remediation of oily industrial effluents contaminated by oil and heavy metals.

Fabrication, characterization and application of ceramic membrane developed from Tunisian natural kaolin clay for textile wastewater treatment are presented in this study. The morphology and properties of the resulting membrane sintered at 1000°C for 3 h were then determined by Scanning Electron Microscopy (SEM), mechanical and chemical resistance and water permeability. Separation performance of the membrane was evaluated during the treatment of textile wastewater. SEM images reveal the homogeneous surface of the membrane. The membrane displayed good chemical and mechanical resistances as well. Its permeability was of 21.2 L.h -1 .m -2 .bar -1 , indicating that separation performance could occur in the domain of Ultrafiltration (UF). Performances of the membrane during the treatment of raw and biologically pretreated textile effluents are promising in terms of the removal of colour (99% for the raw effluent and 100% for the biologically pretreated effluent), chemical oxygen demand (COD) (80% for the raw effluent and 93% for the biologically pretreated effluent) and turbidity (98% for the raw effluent and 100% for the biologically pretreated effluent).

This paper presents a synthesis of mesoporous silica (MS) from natural clay as a silica source using Pluronic L35 (EO11PO16EO11) as a structure-directing agent. The prepared material was characterized by XRD, X-ray fluorescence, thermogravimetric analysis, SEM, TEM, and N2 adsorption-desorption analyses. Then, mesoporous material was used for the removal of Acid Red 337 (AR337) from aqueous solution, and the treatment of real textile effluent. The effect of pH, contact time, weight of adsorbent, and initial concentration was studied in batch adsorption. The synthesized mesoporous material showed good discoloration efficiency with a 62% percentage. Experiment with real textile wastewater showed that 39%, 40%, and 31.5% of the color, TOC, and chemical oxygen demand respectively were eliminated by using 1 g of MS per liter of wastewater.

Biomass as a renewable energy source has become increasingly prevalent in Europe to comply with greenhouse gas emission targets. As one of the most efficient perennial bioenergy crops, there is great potential in the Upper Rhine Region to explore biomass utilization of Miscanthus to confront climate change and land use demand in the future. Yet, the impacts of Miscanthus cultivation on soil quality have not been adequately explored. This study investigated the soil profiles of five- and 20-year-old Miscanthus fields (1 m depth) as well as grassland for reference in eastern France and Switzerland. The soil organic carbon (SOC) concentrations and δ13C compositions of four soil layers (0-10 cm, 10-40 cm, 40-70 cm and 70-100 cm) were determined. The CO2 emission rates of the topsoil were monitored for 42 days. Our results showed that Miscanthus, in general, could increase the SOC stocks compared to grassland, but the benefits of SOC sequestration were constrained to the surface soil. Isotopically, the Miscanthus-derived SOC ranged from 69% in the top 10 cm of soil down to only 7% in the 70 cm to 100 cm layer. This result raises the risk of overestimating the total net benefits of Miscanthus cultivation, when simply using the greater SOC stocks near the surface soil to represent the SOC-depleted deep soil layers. The Miscanthus fields had greater CO2 emissions, implying that the Miscanthus fields generated greater ecosystem respiration, rather than larger net ecosystem exchanges. Compared to the grassland soils, the surface soils of the Miscanthus fields tended to have a risk of acidification while having higher concentrations of phosphorus and potassium, calling for the inclusion of soil characteristics and SOC stability when evaluating the impacts of long-term Miscanthus cultivation on both current and future land use changes., Competing Interests: The authors have declared that no competing interests exist.

Understanding the fate of copper (Cu) fungicides in vineyard soils and catchments is a prerequisite to limit the off-site impact of Cu. Using Cu stable isotopes, Cu retention in soils and runoff transport was investigated in relation to the use of Cu fungicides and the hydrological conditions in a vineyard catchment (Rouffach, Haut-Rhin, France; mean slope: 15%). The δ(65)Cu values of the bulk vineyard soil varied moderately through the depth of the soil profiles (-0.12 to 0.24‰±0.08‰). The values were in the range of those of the fungicides (-0.21 to 0.11‰) and included the geogenic δ(65)Cu value of the untreated soil (0.08‰). However, δ(65)Cu values significantly differed between particle-size soil fractions (-0.37±0.10‰ in fine clays and 0.23±0.07‰ in silt). Together with the soil mineralogy, the results suggested Cu isotope fractionation primarily associated with the clay and fine clay fractions that include both SOM and mineral phases. The vegetation did not affect the Cu isotope patterns in the vineyard soils. Cu export by runoff from the catchment accounted for 1% of the applied Cu mass from 11th May to 20(th) July 2011, covering most of the Cu use period. 84% of the exported Cu mass was Cu bound to suspended particulate matter (SPM). The runoff displayed δ(65)Cu values from 0.52 to 1.35‰ in the dissolved phase (<0.45μm) compared to -0.34 to -0.02‰ in the SPM phase, indicating that clay and fine clay fractions were the main vectors of SPM-bound Cu in runoff. Overall, this study shows that Cu stable isotopes may allow identifying the Cu distribution in the soil fractions and their contribution to Cu export in runoff from Cu-contaminated catchments., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Six observations of epidermoid cysts of the cranial vault in children are reported. The main clinical sign is a cranial tumefaction; the radiological data consist in an edged osseous gap; the surgical extraction of this evolutional tumor is indicated.

This work corroborates anatomical data well known since G. Lazorthes about the main trunk of the middle cerebral artery. The data are interesting in various fields: Sylvian aneurysms, big sphenoïd ridge meningiomas, extra-intra cranial micro neurosurgical anastomoses. This work is based upon 280 angiographic pictures, 20 dissections of brain arteries and 12 plastic injections of the brain arterial vascular tree. The most important data to point out are variations of length and of division (no division, simple bifurcation, trifurcation or multiple divisions), variability in the central arteries and some rare anomalies like accessory middle cerebral arteries and duplication.

The cystic dilation of the sub-arachnoidal space individualised by Tarlov in 1938, may be integrated in the diagnosis of non discal surgical sciatica. The classification proposed by Lazorthes sumes up the eventualities encountered at the lombo-sacral level. The clinical study of five personal observations and the analysis of literature enable the establishment of a clinical picture evoking the anomaly. It would appear that the affection is characterised by lumbago or lumbo-sciatica, the attacks separated by free intervals. In an acute period the algia lessens in the Trendelenbourg position. A significant sign would be the pain on moving the sacrum. Among the complementary examination the radiographic study of the sacrum with tomographies is indisplusable, the diagnosis is based on the radiography of spinal nerve roots with late time in a vertical position. Medico-surgical treatment is in order, it gives a favorable result when surgical criteria have respected: invalidating evolutive algia with or without a clear sign of deficiency. The surgical result is essentially conditioned by a strict indication.

The last 60 patient who underwent surgery for neurinoma or meningioma of the spine provide the basis for this report. One-fourth of all cases of spinal cord compression are due to meningioma or neurinoma. Attention is drawn to the characteristic clinical features of these tumors, particularly their time-course, since diagnosis if often delayed. The sooner diagnosis is established, the better postoperative recovery will be, especially in elderly patients (60% of cases). Results of operative treatment are presented.

Over a period of 9 years, 139 patients with a mean age of 61 years were operated upon for disorders due to narrow lumbar vertebral canal. Clinical expression varied: lumbago, movement sciatica, intermittent claudication... Importance must be attached to discordance of examination findings in apparently benign root pain (67% of cases). The two key examinations of radiologic investigation are radiculography and a CT scan. Treatment is surgical, generally by a two-stage wide laminectomy combined with abrasion of an articular facet (64%), excision of osteophytic pads (35%) and/or treatment for a soft herniated disc (26%). Recovery was obtained in 35% of cases and pronounced improvement in 49% (84% of very good and good results) as evaluated by patients and surgeons.

From 300 cases of spontaneous intracerebral hematomas, 5 parameters are extracted they are: Age, sex, level of consciousness, localisation of hematomas and risk factors. A value, varying from 1 to 5 is attributed to each parameter, the sum of values give a score for each patient. This score allows the clinician to predict, within the early 48 hours, the vital prognosis. Survival chances are: 80% if score between 5 and 8; 60% if score between 9 and 13; 40% if score between 14 and 17; 20% if score equal or superior to 18.