The reactive surface of Castor leaf [Ricinus communis L.] powder as a green adsorbent for the removal of heavy metals from natural river water

In this study, a green adsorbent was successfully applied to remove toxic metals from aqueous solutions. Dried minced castor leaves were fractionated into 63-μm particles to perform characterization and extraction experiments. Absorption bands in FTIR (Fourier Transform Infrared Spectroscopy) spectra at 1544, 1232 and 1350 cm-1 were assigned to nitrogen-containing groups. Elemental analysis showed high nitrogen and sulfur content: 5.76 and 1.93%, respectively. The adsorption kinetics for Cd(II) and Pb(II) followed a pseudo-second-order model, and no difference between the experimental and calculated Nf values (0.094 and 0.05 mmol g-1 for Cd(II) and Pb(II), respectively) was observed. The Ns values calculated using the modified Langmuir equation, 0.340 and 0.327 mmol g-1 for Cd(II) and Pb(II), respectively, were superior to the results obtained for several materials in the literature. The method proposed in this study was applied to pre-concentrate (45-fold enrichment factor) and used to measure Cd(II) and Pb(II) in freshwater samples from the Paraná River. The method was validated through a comparative analysis with a standard reference material (1643e). © 2013 Elsevier B.V. © 2013 Elsevier B.V. All rights reserved.

Search in leptonic channels for heavy resonances decaying to long-lived neutral particles

A search is performed for heavy resonances decaying to two long-lived massive neutral particles, each decaying to leptons. The experimental signature is a distinctive topology consisting of a pair of oppositely charged leptons originating at a separated secondary vertex. Events were collected by the CMS detector at the LHC during pp collisions at √s = 7 TeV, and selected from data samples corresponding to 4.1 (5.1) fb-1 of integrated luminosity in the electron (muon) channel. No significant excess is observed above standard model expectations, and an upper limit is set with 95% confidence level on the production cross section times the branching fraction to leptons, as a function of the long-lived massive neutral particle lifetime. Copyright CERN.

The Netherlands Antilles: trade and integration with CARICOM

Introduction The Netherlands Antilles is an autonomous entity within the Kingdom of the Netherlands and comprises a federation of five Caribbean islands: Bonaire and Curacao (the Leeward islands) which comprise 80 per cent of the population of 211,000 and Saba, St. Eustatius and the southern part of St. Maarten (the Windward islands). Like the other countries in the Kingdom, it enjoys full autonomy in internal matters as, for example, education, public health, justice and customs. It has a per capita income of about US$ 12,000. The Leeward Islands and the Windward Islands account for about 75 per cent (Curacao (70 per cent) and Bonaire (5 per cent)) and 25 percent respectively of the economy of the Netherlands Antilles. The Netherlands Antilles has its own currency, the Netherlands guilder, which is pegged to the United States dollar at a fixed rate since 1971. The economy has some unique features that stem from its close relations with the Netherlands, its undiversified nature and heavy dependence on tourism, offshore finance, oil refining and shipping, the high share of trade (exports of goods and services of about 75 per cent of GDP), its geographical characteristics, its common border with the French Republic on St. Maarten, its duty-free access for imports from Aruba, its de facto free trade zone (FTZ), partial dollarization, especially for the Windward Islands, and its highly regulated labor market (1). Adverse economic shocks in the last two decades affected particularly the offshore financial sector and the oil refinery and, to a lesser extent, tourism. The repeal of withholding taxes in the United States in the 1980s indirectly caused the collapse of a number of highly profitable offshore financial activities in Curacao, leading to significant drops in government revenue and contributions to foreign exchange earnings. The withdrawal of Shell from Curacao in 1986 and the (temporary) closure of the oil refinery which had been a mainstay of the Curacao economy for almost three quarters of a century was the second major shock. It was subsequently leased to the Venezuelan State Company, Petroleos de Venezuela Sociedad Anonima (PDVSA), which resumed operations and preserved employment. In the 1990s, the Windward Islands were bit by several devastating hurricanes, which destroyed much of the economic infrastructure on the islands, including about half of the number of available hotel rooms in St Maarten. Further negative shocks were related to the discontinuation of certain trade privileges on European markets for Overseas Countries and Territories (OCTs), the withdrawal by the Netherlands of certain tax privileges for Dutch pensioners residing in the Netherlands Antilles and disruptions in the availability of Solidarity Fund resources for the smaller islands. National income has been on the decline since 1997. GDP declined by about 6 per cent between 1997 and 1999. Underlying fiscal imbalances and structural weaknesses have also impacted negatively on the economy. In recent years, with recession high unemployment and migration have been experienced (2). The Netherlands Antilles has been able to survive thanks to additional aid from the Netherlands, large-scale spontaneous emigration (mostly to the Netherlands), some drop in international reserves, an increase in domestic debt and arrears and reduced outlays for the maintenance of public assets. From 1986 onwards, successive efforts at restoring macroeconomic balance, particularly with regard to public finance, were made, but were unsuccessful. Adjustment was also attempted in 1996 and 1997, but failed to meet the desired targets. In 1999, the government launched a new National Recovery Plan" (NRP). The NRP contains important medium-term structural adjustment measures aimed at restoring macroeconomic balance and conditions for revitalizing the economy. The NRP subsequently served as an important input into a comprehensive adjustment plan drawn up with the assistance of the International Monetary Fund (IMF) and reflected in the government's Memorandum of Economic Policies dated 15 September 2000. Beyond restoring macroeconomic balance and reforming the economic incentive framework, the government aims at establishing a Comprehensive Development Framework (CDF) for the formulation and implementation of a sustainable long-term growth strategy. It is against the above background that this study is undertaken. Its main objective is to assess the integration options facing the Netherlands Antilles (3) vis-a-vis the Caribbean Community (CARICOM). A secondary objective is to examine the above taking into account, inter alia, the level of trade between the Netherlands Antilles and CARICOM, the barriers to trade between the two groups of countries and the requirements for increasing trade between the two groups of countries. The Consultant was given an initial Draft Terms of Reference (Annex 1) with the intention of modifying it in the course of the interviews with all the stakeholders. The main idea that emerged from these interviews was a concern with some possible form of association with CARICOM. The Consultant was asked to exam the costs and benefits of various forms of association and to recommend an option. This adjustment of the Terms of Reference (TOR) was substantial and involved the Consultant having to do some interviews and collect documentation in CARICOM. The study essentially revolves around the search for a road map for the Netherlands Antilles. It is tackled in the first instance by describing the existing system of trade of the Netherlands Antilles with a view to determining the import and export structures and the specific nature and extent of trade in goods and services between the Netherlands Antilles and CARICOM. 1 Netherlands Antilles: Elements of a Strategy for Economic Recovery and Sustainable Growth. Interim Report of the World Bank Mission, 5-20 December 2000. 2 IMF, IMF Country Report No. 01/73 Kingdom of the Netherlands-Netherlands Antilles-Recent Development, Selected Issues and Statistical Appendix. May 2001 3 The Netherlands Antilles is a country within the Kingdom of the Netherlands. It contains five islands. Curacao and Bonaire (Leewards) and St Eustatius, Saba and St Maarten (The Windwards)"

Provisional customs tariff for the East Caribbean Common Market with list of conditional duty exemptions and reductions

Includes bibliography

Heavy mineral as a tool to refine the stratigraphy of kaolin deposits in the Rio Capim Area, Northern Brazil

Estudos de minerais pesados provenientes em depósitos cauliníticos da Formação Ipixuna na região do rio Capim (Brasil) revelaram uma mineralogia matura a supermatura, representada dominantemente por zircão e turmalina e, subordinadamente, rutilo, cianita e estaurolita. Os minerais encontrados não variam muito, entretanto cada unidade caulinítica apresenta uma assinatura particular definida por diferenças nasproporções entre os principais minerais, assim como em suas características texturais. Este trabalho demonstrou que asunidades de caulim soft (inferior) e semi-flint (superior) podem ser consideradas seqüências deposicionais distintas. As altas percentagens de opacos em relação aos minerais transparentes e altos teores de zircão são diagnósticos da unidade caulinítica inferior. O incremento no volume de grãos de zircão e turmalina arredondados a subarredondados na unidade caulinítica superior sugere que esta inclui grãos que foram submetidos a um grau mais elevado de retrabalhamento. O aumento no volume de grãos não alterados de estaurolita e cianita na unidade superior leva a concluir que, além da reciclagem sedimentar, uma fonte distinta deve ser invocada. Estes resultados também mostram que as características da assembléia de minerais pesados da unidade intermediária são comparáveis com aqueles da unidade superior, o que sugere mesmo posicionamento estratigráfico.

Application of bauxite waste from amazon region in the heavy clay industry

In this work, a method was developed for the application of red mud, an alkaline leaching waste, from a bauxite processing plant located in northern Brazil (Amazon region) as starting material for heavy clay products. Samples were prepared by pressing blends of red mud and clay, which were then fired at temperatures from 900 ºC to 1190 ºC. Characterization was carried out by chemical analysis, differential thermal analysis (DTA) and X-ray diffraction (XRD), and the following ceramic properties were evaluated: water absorption, linear shrinkage and flexural strength. In order to evaluate the Na⁺ stability in the dense ceramic, leaching tests were also carried out on the specimens after sintering process. Results indicated that samples with 50 and 70 wt% of red mud are proper for being used in the production of ceramic bodies, due to its excellent properties, mainly high mechanical resistance and low water absorption, showing thus, an option to minimizing the environmental impacts caused by the aluminum industry.

Desorption of heavy metals from ion exchange resin with water and carbon dioxide

Adsorption and regeneration of ion exchange resins were studied using a subcritical solution of a CO₂-H₂O mixture and a fixed bed column. The commercial Amberlite IRC-50/IRC-86 cation exchange resins and Amberlite IRA-67 anion exchange resin were tested for heavy metals (Pb, Cu, Cd) adsorption from a solution with different initial metal concentrations at different temperatures. After adsorption, the loaded resins were regenerated with water and carbon dioxide at different temperatures and a pressure of 25 MPa. The efficiency of the IRC-50 resin was lower than that of the IRC-86 resin for the adsorption of metals like Cd, Cu and Pb. Results obtained for desorption of these metals indicated that the process could be used for Cd and in principle for Cu. Sorption of metal ions depended strongly on feed concentration. Mathematical modeling of the metal desorption process was carried out successfully as an extraction process. For this purpose, the VTII Model, which is applied to extraction from solids using supercritical solvents, was used in this work.

Search for heavy narrow dilepton resonances in pp collisions at root s=7 TeV and root s=8 TeV

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Search for heavy resonances in the W/Z-tagged dijet mass spectrum in pp collisions at 7 TeV

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Searches for light- and heavy-flavour three-jet resonances in pp collisions at root s=8 TeV

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Heavy metals in cowpea (Vigna unguiculata L.) after tannery sludge compost amendment

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Heavy Metals Extracted by DTPA and Organic Acids from Soil Amended with Urban or Industrial Residues

Understanding soil responses to the application of urban or industrial residues is necessary. In the current experiment, both sources of residues were applied to the soil surface of a Hapludox soil for 8 years. The four residues studied were biodigested and centrifuged sewage sludge (LB and LC, respectively), steel slag from the metallurgic industry (E), and limed mud from the pulp and cellulose industry (LCal). The residues were applied at 0, 2, 4, and 8 Mg ha(-1) four times from 2002 to 2010 when soybean was cultivated in the summer and lopsided oat and sorghum were cultivated during the winter. The contents of heavy metals were evaluated with diethylenetriaminepentaacetic acid (DTPA) and organic acids. The LB was the residue that increased the contents of soil micronutrients and heavy metals to their greatest levels, although within limits that impair the risks of environmental contamination.

A split-mouth randomized clinical trial of conventional and heavy flowable composites in class II restorations

Objective: The aim of this study was to evaluate the 2-year clinical performance of class II restorations made with a composite resin with two different viscosities.Methods: 47 patients received two class II restorations (n = 94), one made with GrandioSO (conventional viscosity CV), and the other with GrandioSO Heavy Flow (flowable viscosity FV), subjecting both materials to the same clinical conditions. The self-etching adhesive Futurabond M was used for all restorations. The composites were inserted using the incremental technique. The restorations were evaluated using the modified USPHS criteria according to the periods: baseline, 6 months, 1 year and 2 years after restorative procedures.Results: After 24 months, 40 patients attended the recall and 78 restorations were evaluated. In all periods, no secondary caries was observed. After 6 months, there were slightly overall changes of scores for most parameters. After 24 months, the higher number of changes from score Alfa to Bravo was observed for marginal discolouration (32.5% CV and 39.5% FV) and colour match (15% CV and 31.6% FV), followed by proximal contact (25% CV and 23.7% FV) and marginal adaptation (20% CV and 21.1% FV). For wear, surface texture and postoperative sensitivity the changes were very small. Just two restorations were lost during the 24-month follow up. Less than 5% of all restorations showed postoperative sensitivity. Chi-square test showed no significant differences between the two materials for all parameters analysed.Conclusion: After 2 years of clinical service, no significant differences were observed between GrandioSO conventional and GrandioSO Heavy Flow for the parameters analysed. Both materials provided acceptable clinical behaviour in class II restorations. Clinical Significance: This study presents the possibility of using a flowable composite with high filler content, for performing class II restorations. (C) 2014 Elsevier Ltd. All rights reserved.

Heavy metals and yield of cowpea cultivated under composted tannery sludge amendment

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Cardiac autonomic regulation during exposure to auditory stimulation with classical baroque or heavy metal music of different intensities

Objectives: The effects of chronic music auditory stimulation on the cardiovascular system have been investigated in the literature. However, data regarding the acute effects of different styles of music on cardiac autonomic regulation are lacking. The literature has indicated that auditory stimulation with white noise above 50 dB induces cardiac responses. We aimed to evaluate the acute effects of classical baroque and heavy metal music of different intensities on cardiac autonomic regulation. Study design: The study was performed in 16 healthy men aged 18-25 years. All procedures were performed in the same soundproof room. We analyzed heart rate variability (HRV) in time (standard deviation of normal-to-normal R-R intervals [SDNN], root-mean square of differences [RMSSD] and percentage of adjacent NN intervals with a difference of duration greater than 50 ms [pNN50]) and frequency (low frequency [LF], high frequency [HF] and LF/HF ratio) domains. HRV was recorded at rest for 10 minutes. Subsequently, the volunteers were exposed to one of the two musical styles (classical baroque or heavy metal music) for five minutes through an earphone, followed by a five-minute period of rest, and then they were exposed to the other style for another five minutes. The subjects were exposed to three equivalent sound levels (60- 70dB, 70-80dB and 80-90dB). The sequence of songs was randomized for each individual. Results: Auditory stimulation with heavy metal music did not influence HRV indices in the time and frequency domains in the three equivalent sound level ranges. The same was observed with classical baroque musical auditory stimulation with the three equivalent sound level ranges. Conclusion: Musical auditory stimulation of different intensities did not influence cardiac autonomic regulation in men.