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The paper presents the results of experimental study of the adsorption characteristic of the IM-50 and tall oil fatty acids (TOFA) collector reagents on cassiterite. UV-spectrophotometric method, scanning electron and laser microscopy were applied to analyze the adsorption of the reagents. SHIMADZU UV 1800 was used to obtain the UV spectra of aqueous solutions of IM-50 reagents and saponified TOFA at varied concentrations. IM-50 has not got characteristic adsorption maxima in ultraviolet and visible spectrum. TOFA has a weakly pronounced maximum absorption in the range of 233-244 nm. Microscopic photographs of cassiterite sections were obtained with LEO 1420VP INCA equipped OXFORD ENERGY 350 analyzer. Reagent IM-50 and TOFA collector reagent, Newly formed organic matter phases of IM-50 and TOFA were detected. X-ray spectra characterized the increased carbon content indicating adsorption on the surface of cassiterite IM-5- and TOFA. By measuring the surface relief parameters of polished cassiterite, using KEYENCE VK-9700 scanning laser microscopy and VK-Analyzer software, a qualitative and quantitative assessment of the IM-50 and TOFA reagent layer on the cassiterite surface was performed. Measurements were performed in the several fields of view and showed the degree of IM-50 coating varied from 40.5 to 42.6% of the surface area, and TOFA average coating was 38.5%. Subsequent washing with water does not remove the reagents from the surface of the mineral and indicates a strong fixation of IM-50 and TOFA on cassiterite, which can have a positive effect on flotation extraction of sludge tin fractions. Qualitative and quantitative results of the reagent adsorption helped to make a forecast of their floatability by the studied collectors. This study is supported by the Russian Science Foundation (project No. 17-17-01292). [ABSTRACT FROM AUTHOR]

The Huanggang iron–tin polymetallic skarn deposit is located in the southern Great Xing'an Range. According to the ore types and mineral assemblages, the paragenetic sequence of the Huanggang deposit can be divided into three stages, and these magnetite grains were mainly formed at the retrograde and sulphide skarn stages. The magnetite (sample HG12‐13) from the early retrograde stage is represented by fine‐grained magnetite cutting across coarse‐grained magnetite surrounded by quartz and calcite. The magnetite (sample HG12‐73) from the late retrograde stage is locally replaced by haematite along the margin or interior and is surrounded by calcite. The magnetite (sample HG12‐88) from the early sulphide stage is characterized by obvious core–rim textural features. The magnetite (sample HG‐62) from the late sulphide stage is featured by zone‐like magnetite occurring along the margin and interior of the primary magnetite. Laser ablation inductively coupled plasma mass spectrometry was used to obtain trace element concentrations of magnetite from the different mineralization stages in order to better understand the geochemical variations in the ore‐forming process. Some magnetite grains have abnormally high Mg, Al, K, Cu, Zn, and Sn due to the presence of numerous inclusions (e.g., chlorite, sylvite, chalcopyrite, sphalerite, and cassiterite). In general, magnetite grains from the different mineralization stages demonstrate similar bulk continental crust normalized trace elements patterns, suggesting that they share a similar origin. The increasing Si + Al/Mg + Mn ratios and decreasing Mg + Mn contents for magnetite show an increasing fluid–rock ratio from the retrograde to sulphide stage. Co contents of magnetite decrease abruptly from the retrograde stage to the sulphide stage, whereas Mn contents show the reverse trend, which is affected by minerals coprecipitating with magnetite. A zoned magnetite from the sulphide stage shows decreasing Ti and V contents from core to outer rim; the variation of Ti and V may be related to the temperature or oxygen fugacity. Magnetite compositions from the Huanggang deposit are similar to those from Fe, Cu‐polymetallic, or other skarn deposits, but display more variable compositions than previously presented. Our study demonstrates that the evolution of magnetite in the skarn deposit and trace element of magnetite could be a powerful tool in determining the origin of skarn iron deposit. [ABSTRACT FROM AUTHOR]

The southwestern South China Block, composed of southwestern China and northeastern Vietnam, is one of the most important Sn-polymetallic ore districts in the world. The Dulong skarn Sn-polymetallic deposit, which is closely related to Late Cretaceous granitic magmatism, contains 5.0 mt Zn, 0.4 mt Sn, 0.2 mt Pb, and 7 kt In, and is one of the largest Sn-polymetallic deposits in the region. Sn mineralization occurs mainly as cassiterite at the contact zone between the Laojunshan granitic pluton and carbonates of the Cambrian Tianpeng Formation. The Laojunshan granitic pluton consists of three: medium- to coarse-grained two-mica monzonitic granite, medium- to fine-grained two-mica monzonitic granite, and granite porphyry, with zircon U–Pb ages of 87.5 ± 0.6 Ma, 85.3 ± 1.1 Ma, and 82.8 ± 1.6 Ma, respectively. Zircon grains from these three phases show ε Hf (t) values from −9.5 to −2.5, typical of a mantle origin. All samples exhibit strongly peraluminous and high-K calc-alkaline affinities, and show trace element patterns characterized by enrichment in Rb, Ta, La, Zr, and Hf, and depletion in Ba, Nb, and Ti, typical of S-type granites. Three main alteration/mineralization stages are recognized within the mineralized contact zones: (1) skarn stage; (2) sulfide mineralization stage; and (3) supergene stage. Cassiterite grains from the skarn alteration stage yield a 207 Pb/ 206 Pb– 238 U/ 206 Pb concordia age of 89.4 ± 1.4 Ma, suggesting that mineralization was associated with the Laojunshan granitic pluton. Regionally, the Sn-polymetallic mineralization in the southwestern South China Block took place within a narrow time span from 97 to 79 Ma. The causative granitic magmas can be produced by partial melting of the Paleoproterozoic–Mesoproterozoic pelitic basement rocks during large-scale lithospheric thinning and asthenospheric upwelling. [ABSTRACT FROM AUTHOR]

The recently discovered Sanjiaowo Sn deposit is located in eastern Guangdong, SE China. The Sn mineralization, hosted in granite porphyry and the Lower Jurassic Jinji Formation low-grade metamorphic wall rocks, is considered to be granite-related. Zircon U–Pb dating of the granite porphyry yielded concordant ages of 140.5 ± 1.4 Ma, which is consistent with the cassiterite U–Pb age of 139.8 ± 5.0 Ma, indicating a temporal link between the emplacement of granitic plutons and Sn mineralization. The granite porphyry samples are weakly peraluminous and show an A-type geochemical signature with high Na 2 O + K 2 O (7.19–8.51 wt.%), REE (261–308 ppm), Zr + Nb + Ce + Y (353–476 ppm) contents, FeO T /MgO (0.93–0.99), and Ga/Al (2.65–3.42) ratios. They display bulk rock initial 87 Sr/ 86 Sr of 0.7110 to 0.7165, εNd(t) of −5.90 to −4.04, and zircon εHf(t) values from −8.36 to −4.16 with Mesoproterozoic T DM2 ages for both Nd and Hf isotopes. Detailed elemental and isotopic data suggest that the Sanjiaowo Granite porphyry belongs to the A 2 -subtype and were formed by partial melting of a crustal source of Mesoproterozoic overall residence age with minor input of mantle materials. The low calculated zircon Ce 4+ /Ce 3+ (6.5–81.2) and Eu N /Eu N ∗ (0.05–0.24) ratios demonstrates that the Sanjiaowo granitic magma had a low oxygen fugacity, which may have facilitated the Sn enrichment and played a key role in the Sn mineralization. Lead isotopes indicate that there is no difference for 206 Pb/ 204 Pb, 207 Pb/ 204 Pb, and 208 Pb/ 204 Pb ratios between the granite porphyry and the sulfide minerals from the orebodies. Moreover, the sulfur isotopic compositions for the sulfides (pyrite and pyrrhotite: δ 34 S = −1.6–1.0‰, average = −0.32) is similar to magmatic δ 34 S, but different from the δ 34 S in the Jinji Formation strata. Consequently, these data favor of a magmatic-hydrothermal origin for the Sn mineralization in the Sanjiaowo deposit. Integrating new and published data on the tectonic evolution, we suggest that the granite porphyry and associated Sn mineralization in the Sanjiaowo deposit formed in a back-arc extensional environment at ∼141 Ma, related to the rollback of the paleo-Pacific Plate. [ABSTRACT FROM AUTHOR]

The proven global tin reserves were reported to be approximately 4.7 million tons (Mts) in 2016, and among these resources, only approximately 2.2 Mts can be recovered economically. The original tin deposits will be exhausted in several years, therefore, tin-bearing secondary resources, such as tin alloy, tin anode slime, e-wastes, tin slag and tin-bearing tailings, will become the primary source from which tin can be extracted. Many investigations have been conducted on the recovery of tin from these tin-bearing materials. However, the separation and recovery approaches of tin vary significantly, since the content and phase compositions of tin are totally different in these secondary resources. This paper reviews these methods of extracting and separating tin from different kinds of tin-bearing secondary resources. [ABSTRACT FROM AUTHOR]

The recently discovered Jinkeng deposit, located in eastern Guangdong Province, SE China, is a granite-related cassiterite–sulfide-type Sn–Cu–Pb–Zn deposit in the Cathaysia Block. Zircon U–Pb dating of the biotite granite and fine-grained granite associated with the deposit yielded concordant ages of 144.7 ± 0.8 Ma and 141.1 ± 1.3 Ma, respectively. These ages are consistent, within error, with the molybdenite Re–Os isochron age of 139.3 ± 2.5 Ma for the deposit, indicating a temporal link between the emplacement of granitic plutons and polymetallic Sn mineralization. Combined with the regional mineralization ages, we propose that the 145–135 Ma interval represents another significant period of Sn–W mineralization in southern China, in addition to those already recognized. The biotite granite and fine-grained granite have similar geochemical characteristics; both are weakly peraluminous, high-K and calc-alkaline, containing abundant Si, Na, and K, and low concentrations of Fe, Mg, Ca, and P. Compared to primitive mantle and unfractionated granitoids, they are enriched in Rb, Th, U, K, and Pb, have relatively high Rb/Sr and low K/Rb values, are depleted in Ba, Sr, and Ti, and have prominent negative Eu anomalies (δEu = 0.05–0.19), characteristic of highly fractionated I-type granites. Zircons from these granites have ε Hf (t) values ranging from − 9.2 to − 3.3, and Hf model ages (T DM2 ) of 1776–1406 Ma, suggesting that the granites formed by the partial melting of Proterozoic basement material, and contain a minor mantle-derived component. Highly fractionated and reduced ( f O 2 below NNO) magma facilitated the enrichment of Sn. Existing knowledge on the tectonic evolution of this region and new data from this study, indicate that the granites and associated Sn mineralization in the Jinkeng deposit formed in an extensional environment at ~ 140 Ma, likely related to the rollback of the paleo-Pacific Plate. [ABSTRACT FROM AUTHOR]

The Gejiu tin-copper polymetallic ore field, located at the westernmost end of the Cathaysia Block in South China, is one of the largest tin polymetallic ore fields in the world. It is associated with magmatic-hydrothermal ore-forming processes triggered by deeply seated structures and concealed granites. The Bi-dimensional empirical mode decomposition (BEMD) was used to decompose gravity data covering an area including the Gejiu tin-copper polymetallic ore field in the west and the Bozhushan silver-lead-zinc polymetallic ore field in the east, which yielded three two-dimensional intrinsic mode function (BIMFs) images and one residue ( Res ( m , n )) image that depict four layers of geological architectures at different wavelengths within the study area. The high-pass filtered gravity component image (BIMF 1 ) is interpreted to depict the shallow geological architecture, which indicates that the skarn alteration and tin-copper mineralization with positive gravity anomalies are distributed around the granites characterized by negative gravity anomalies. The band-pass filtered gravity component image (BIMF 2 ) is interpreted to depict the middle-shallow geological architecture, which indicates that the outcropped granites in the western Gejiu ore field bounded by the Gejiu fault may extend to the eastern Gejiu ore field to form one integrated granitic complex in the subsurface. The other band-pass filtered gravity component image (BIMF 3 ) is interpreted to depict the middle-lower geological architecture, which indicates that there may be an EW-trending granite zone with negative gravity anomaly at middle-lower depth connecting the Gejiu tin-copper polymetallic field to the Bozhushan silver-lead-zinc polymetallic field, displaying the existence of an EW-trending regional polymetallic ore-forming zone within the study area. The low-pass filtered gravity component image ( Res ( m , n )) is interpreted to depict the lowest geological architecture within the study area, which reflects that there may be a pair of the NW-trending uplift zone of the mantle and/or the basement with positive gravity anomaly and the depression zone of the mantle and/or the basement with negative gravity anomaly. The Gejiu tin-copper polymetallic deposits and the related granites are located at the transitional zone between the uplift and depression, whereas the Bozhushan silver-lead-zinc polymetallic deposits and the related granites are situated within the depression zone, which implies that the diversity of the Late Yanshanian granites and the related polymetallic deposits in the study area may be controlled by the complexity of the crust-mantle interaction at depth. [ABSTRACT FROM AUTHOR]

Monazite [(Ce,Th)PO4] from the Llallagua tin ore deposit in Bolivia is characterized by low radiogenic element contents. Previously reported field evidence and mineral associations suggest the mineral formed via direct precipitation from hydrothermal fluids. Monazite compositions thus may provide insight into characteristics of the fluids from which it formed. Chemical compositions of three Llallagua monazite grains were obtained using Electron Probe Microanalysis (EPMA, n = 64) and laser ablation mass spectrometry (LA-ICP-MS, n = 56). The mineral has higher amounts of U (123 ± 17 ppm) than Th (39 ± 20 ppm) (LA-ICP-MS, ±1σ). Grains have the highest amounts of fluorine ever reported for monazite (0.88 ± 0.10 wt %, EPMA, ±1σ), and F-rich fluids are effective mobilizers of rare earth elements (REEs), Y, and Th. The monazite has high Eu contents and positive Eu anomalies, consistent with formation in a highly-reducing back-arc environment. We speculate that F, Ca, Si and REE may have been supplied via dissolution of pre-existing fluorapatite. Llallagua monazite oscillatory zoning is controlled by an interplay of low (P + Ca + Si + Y) and high atomic number (REE) elements. We suggest monazite compositions provide insight into fluid geochemistry, mineral reactions, and tectonic settings of ore deposits that contain the mineral. [ABSTRACT FROM AUTHOR]

In the present work microstructural and chemical analysis of tin and slag that resulted from three smelting experiments reconstructing prehistoric conditions are presented. Cassiterite ores were collected from northwestern (NW) Iberian deposits and were smelted in a small open pit. Results show that the loss in tin can be very high, up to 80%, mainly as a result of volatilization of Sn species. The experiments show that using handmade leather bag bellows and clay tuyeres, temperatures can easily reach >1200°C. The tin produced was a very pure (Sn) solid solution, with the presence of dispersed inclusions or phases of various composition. These included FeSn and FeSn2 intermetallics and small metallic W inclusions. Slags could be grouped into three types based on their physical characteristics, and bulk chemical analysis could relate each type as being a product from the reaction of ore material or a product from the reaction with the crucible material. Generally, it was found that in spite of very low recovery rates, the tin produced by this simple technique would have been adequate for a domestic small-scale production. [ABSTRACT FROM AUTHOR]

To investigate the potential of tourmaline as a geochemical monitor, a comprehensive dataset on major, minor and trace element concentrations as well as Fe 3+ /ΣFe ratios of tourmaline is presented. The dataset includes samples from five plutonic complexes related to diverse magmatic to hydrothermal stages of the Cornubian Batholith (SW England). Tourmaline composition found in barren and cassiterite-bearing samples include all three primary tourmaline groups and tourmaline species with the general endmembers schorl, dravite, elbaite, uvite, feruvite, foitite and Mg-foitite. Based on textures and compositions, it is possible to distinguish not only between late-magmatic and hydrothermal tourmaline, but also between several formation stages. Hence, tourmaline monitors late-magmatic processes and the partitioning of elements during exsolution of an aqueous phase. For example, in hydrothermal tourmaline Sn is strongly enriched, while Ti, Cr, V and Sc are depleted compared to late-magmatic tourmaline of the same sample. Several tourmaline generations that precipitated from magmatic fluids can be distinguished with differing major and minor elements and REE patterns depending on the composition of the melt from which they were expelled from. Strongly zoned tourmaline allows for unraveling the hydrothermal history of a distinct location including ore precipitation. The precipitation of SnO 2 in the study area was probably caused by mixing between acidic, reduced, Sn-bearing magmatic fluids and oxidized meteoric fluids, which is in agreement with London and Manning (1995) and Williamson et al. (2000) . Hence, the ability of tourmaline composition to monitor changes in Sn concentration and redox conditions in hydrothermal fluids has potential as an exploration tool. [ABSTRACT FROM AUTHOR]

Gravity separation is typically used in the beneficiation of tin ores as the density difference between the valuable and associated gangue minerals is significant. In the present investigation, a cassiterite sample collected from the Uljin deposit in South Korea has been subjected to different gravity separators to evaluate the separation efficiency. The selection of gravity units has been made based on performance evaluation following heavy liquid separation and assessment of grade/recovery curves and Tromp curve methods. In addition, a gravity separation index (GSI) has been proposed that is simpler than other methods for assessing the performance of gravity separators. [ABSTRACT FROM AUTHOR]

The recently installed and unique PIXE (particle-induced X-ray emission) set-up at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) is mainly dedicated to applications for a detailed overview of elemental composition over large sample areas within a short time even at trace level. The so-called High-Speed-PIXE (HS-PIXE), a combination of a pnCCD-based pixel-detector with polycapillary X-ray optics, offers simultaneous imaging of sample areas up to 12 × 12 mm 2 with a lateral resolution better than 100 μm. Each of the 264 × 264 individual pixels detects X-ray photons in an energy range from 2 keV to 20 keV with an energy resolution of 152 eV (@Mn-K α ). A high precision sample manipulator offers the inspection of areas up to 250 × 250 mm 2 . During first experiments the determined resolution is (76 ± 23) μm using a sample of well-known sharp-edged chromium patterns. Trace element analysis has been performed using a geological sample, a tin ore, with an average Ta-concentration below 0.1 at.%. Fine-zoned structures became visible in the Ta-L α intensity map within only 45 min. The High-Speed-PIXE closes a gap in the analytical process flow chain especially for geoanalytical characterisations. It is a unique and fast detection system to identify areas of interest in comparably short time at large-area scale for further analysis. [ABSTRACT FROM AUTHOR]

Cassiterite is the main ore mineral of Sn deposits, and may be used to date tin mineralization processes/processes. Both isotope dilution thermal ionization mass spectrometer (ID-TIMS) and laser ablation multi-collector inductively coupled plasma mass spectrometer (LA-MC-ICP-MS) have been applied to cassiterite U–Pb dating. Here we show that cassiterite U–Pb dating results using LA-ICP-MS are comparable to those using LA-MC-ICP-MS. Our results also show that Tera–Wasserburg U–Pb intercept age is far better than the previously used 206 Pb/ 207 Pb versus 238 U/ 207 Pb “isochron” age because the latter weighted data points with low proportions of common Pb more heavily, such that introducing larger errors. Moreover, 206 Pb i / 207 Pb changes with age and 238 U/ 207 Pb ratios, such that yields results younger than the real ages with larger errors. Samples with multiple common Pb sources are difficult to date. Nevertheless, multiple common Pb in cassiterite are often associated with fluid inclusions that may be identified and avoided. The precisions of cassiterite U–Pb ages are not as good as zircon ages, but they provide direct dating on the mineralization processes/processes. Therefore, coupled studies on zircon and cassiterite dating may provide constraints on the relation between magmatism ± hydrothermal activities and mineralization. [ABSTRACT FROM AUTHOR]

The article presents an outlook for the chemicals industry in Malaysia as of November 2015. Topics covered include the country's evolution from a commodities-based economy into a technology and engineering hub, the industrial-scale tin ore mining, and the Malaysian economy as the third biggest in Southeast Asia. Also mentioned are the natural rubber production and the introduction of synthetic rubber.

The South Caucasus was a major center of metal production in the Late Bronze and Early Iron Ages. Nowhere is this more clear than in the hills and mountains in the southeastern Black Sea region (ancient Colchis), where exceptionally large numbers of metal production sites have been found. Chemical and microscopic analysis of slagged technical ceramics at these sites illuminates several aspects of both raw copper and tin bronze alloy production. Copper ores were smelted in a complex multi-stage process designed to extract metal from sulfide ores. Technical ceramics served as containers for a range of different reactions, from the first phase of smelting, in which the copper sulfides were likely consolidated into a matte, though later stages of matte processing and metal copper production in smaller crucibles. In addition, a single crucible fragment, recovered from a late 2nd millennium BC slag heap, demonstrates that tin bronze was created by the direct addition of cassiterite tin ore, probably of alluvial origin, to metallic copper. The crucible's context, the use of cassiterite ore rather than tin metal, and a review of local geology suggests that the tin used in this crucible came from nearby, with the most likely source being the Vakijvari and Bzhuzhi gorges roughly 10–15 km away. While a single fragment does not speak to the regularity of this practice, at the very least it raises the possibility that the Colchian bronze industry was based on local rather than imported tin. [ABSTRACT FROM AUTHOR]

Granitic rocks obtained during field excursions of the famed mineralized regions of the Erzgebirge, Germany (mainly tin-bearing), and South China (mainly tungsten-bearing) have been geochemically analyzed and their results are compared with similar (mainly tungsten-bearing) granites in the island-arc setting of Southwest Japan. The studied granitoids all belong to the ilmenite-series. The collision-related Erzgebirge granitoids are rich in K2O and P2O5, have high A/CNK ratios (1.11-1.24, i.e. S type), but are also high in Ga/ Al ratio (i.e., having some A-type characteristics). In South China, the Xihuashan granites, in contrast, are very low in P2O5, and have A/CNK slightly above 1.0 (1.01-1.05), indicative of I type granites. The ( Sn-) W-related granites of southwest Japan have similarly low P2O5 and A/CNK ratios, indicative also of I-type. Both in the Xihuashan and southwest Japan, the tungsten-related granites have high whole-rock δ18O values implying involvement of W-rich crustal rocks. Sn and W contents of the unaltered granites are lowest in the island-arc setting where the related Sn- W deposits are smallest in size relative to the collision and continental margin settings of the Erzgebirge and South China. [ABSTRACT FROM AUTHOR]

China is rich in tin resources, and contains many types of tin deposits. Among the tin deposit types, the cassiterite-sulfide type, skarn type and quartz vein type occupy a large proportion of tin resources and reserves. From the aspect of exploitation and utilization, the most important types are cassiterite-sulfide type and quartz vein type. The cassiterite-sulfide type tin deposits are mainly located in Northern Guangxi and Eastern Yunnan, skarn type deposits are mainly distributed in the ore-concentration areas of South Hunan in Middle Nanling, and the quartz vein type tin deposits are mainly distributed in South China, such as Western Fujian, Middle Jiangxi, Northern Guangzhou and Southern Hunan. The most important metallogenic epoch for tin deposits is the Mesozoic era. The metallogenic geotectonic background is mainly continental environments after orogeny process, with strong tectonic changes, interlaced deep fracture and frequent magmatism. And the most distinctive feature is the well developed Mesozoic granites, which have a close relationship with tin mineralization. Based on the detailed study of the data from 873 tin deposits in China, this paper summarized the metallogenic regularity of tin deposits, classified 20 important metallogenic series of tin or tin-associated deposits, and inferred that the cassiterite-sulfide type, skarn type, quartz vein type and greisen type are the main prediction types of tin resources. Forty-four tin-mineralization belts were divided, among which, 19 belts are the most important. In addition, a series of maps about tin metallogenic belts and tin metallogenic regularity were compiled, aiming to provide theoretical basis for potential estimation and prediction of tin mineral resources. [ABSTRACT FROM AUTHOR]

Methylmercury (from fresh-water fish) and ethylmercury [from thimerosal-containing vaccines (TCVs)] are the most prevalent source of neurotoxic exposure during early life in families consuming fish and using these vaccines. But children living in Amazonian mining environments are exposed to additional toxic metals in waste materials. We studied mercury (Hg) exposure and neurodevelopment in 294 children (105 boys and 189 girls) from Bom Futuro (Rondonia, Brazil), the epicenter of a tin-ore open-pit mine. Hair-Hg (HHg) concentrations and total ethylmercury (from TCVs) were taken from infants and respective mothers during pregnancy. We used bivariate analysis to determine the effect of sex and linear mixed models to assess the association of prenatal and postnatal organic Hg exposures with children's Bayley Scales of Infant Development (BSID) as psychomotor developmental index and mental developmental index (MDI) at 6 and 24 months of age as well as milestones achievements (age of walking and age of talking). Significant differences between boys and girls were observed for both MDI score ( p = 0.0073) and MDI score ( p = 0.0288) at 6 months but not at 24 months. Regression analysis showed that only in boys was there a significant interaction between MDI score with family income ( β = 0.288, p = 0.018) and with birth weight ( β = −0.216, p = 0.036) at 6 months; at 24 months, however, only boys showed a significant association of both MDI score ( β = −0.222, p = 0.045) and MDI score ( β = −0.222, p = 0.045) with neonatal HHg. In boys, age of walking was associated with HHg ( β = 0.188, p = 0.019) and breastfeeding ( β = −0.282, p = 0.000), whereas for girls, age of walking was only associated with breastfeeding ( β = −0.275, p = 0.001). In this mining environment, with only a weak association for prenatal Hg exposure, there was a significant sex difference in neurodevelopment, with boys showing more sensitivity related to BSID delays. [ABSTRACT FROM AUTHOR]

This paper considers electrochemical tin deposition for producing contact elements in integrated circuit packaging. We examine the effect of organic additives to sulfate electrolytes on the growth of local vertical structures, with the aim of suppressing lateral growth of the deposit. [ABSTRACT FROM AUTHOR]

In this study we demonstrate the use of elemental precursors (Cu, Fe, Sn, S) to obtain stannite forms by a solid-state one-pot mechanochemical synthesis. In the processing route, we report the kinetics of the synthesis. For the characterization of the unique nanostructures, X-ray diffraction, specific surface area measurements and SQUID magnetometry methods were applied. CFTS polymorphs with the tetragonal body-centered structure with the average crystallite size 18-19 nm were obtained. The weak ferromagnetic properties of the quaternary nanocrystals after maximum milling time were also documented. [ABSTRACT FROM AUTHOR]

The mineralogy and liberation characteristics of the comminuted Penouta leucogranite host of the Sn-Ta ore were determined. Grinding developed by a combination of high-pressure grinding rolls (HPGR) followed by a ball mill (BM) was compared with a single ball mill process. The mineral characteristics of the grinding products were analyzed using a Tescan Integrated Mineralogical Analyzer (TIMA-X) and X-ray powder diffraction (XRD). The ore contains 103 ppm of Ta and is mainly composed of quartz, albite, microcline, muscovite, and kaolinite. Nb, Ta-rich minerals are columbite-(Mn) and tantalite-(Mn), as well as minor microlite and wodginite. The liberation in the product is high in the size fraction of less than 250 µm (51–52 wt % for columbite-group minerals (CGM) and 74–80 wt % for cassiterite) and reduced in larger particles (8.8–17 wt % for CGM and 28–37 wt % for cassiterite). The recovery in the −250 µm fraction was high, while in the larger fraction it is limited, remaining up to 80 ppm in some tailings. The combined use of HPGR and a BM reduces the particle size distribution of the product and, thus, increases the liberation of the ores. Smaller fractions can be treated directly using gravity methods; however, particles of a size greater than +250 µm should be ground more. [ABSTRACT FROM AUTHOR]