Swell-shrink clays are widely distributed in the Guangxi province of southern China in the form of expansive soils and lateritic clays. They have high particle dispersion, poor permeability, and significant swell-shrink properties. In recent decades, a series of problems closely related to the physical-mechanical properties of the swell-shrink clays have been encountered in various engineering projects. Mineral composition is a critical factor affecting the physical-mechanical properties of these clays. However, determining accurately their mineral compositions is difficult because the analytical methods available are expensive, time consuming, and have a high possibility of errors. Therefore, identifying a method suitable for quantitatively analyzing the mineral composition of the swell-shrink clays is necessary. In the current study several swell-shrink clays, including two expansive soils and four lateritic clays, from the Guangxi region were investigated. Qualitative analytical methods such as differential thermal analysis (DTA) and X-ray diffraction (XRD) were conducted to identify the mineral composition of the soils. The results indicated that the expansive soils were composed mainly of quartz (Qz), montmorillonite (Mnt), illite (Ilt), and kaolinite (Kln). The Baise specimen also contained a certain amount of calcite (Cal), while the lateritic clays primarily contained Kln and goethite (Gth) as well as lesser amounts of Qz and gibbsite (Gbs). On the basis of the aforementioned results, rough quantitative analyses of the mineral compositions were conducted using X-ray fluorescence (XRF) and the Bogue method. The results indicated that the lateritic clay samples from Wuming, Guilin, and Liuzhou contained 70–80% Kln, while the Laibin lateritic clay was 50% Kln. The lateritic clays contained ~10% Gth. The expansive soils were 30–40%, 25–30%, and 10–15% of Ilt, Qz, and Mnt, respectively. Finally, the relationships between the mineral compositions, zeta potentials, and free swelling ratios are discussed briefly. This investigation indicated that the zeta potential was mainly related to the type and content of clay minerals in the soil when neutral water was used as the free solution (pH = 7). The correlation between the swelling index and the zeta potential of the expansive soils was greater than that of the lateritic clays, which indicated that the swelling properties of expansive soils were more affected by the clay mineral composition than those of the lateritic clays. The results provide a systematic method for the qualitative and quantitative analysis of the mineral composition of swell-shrink clays and primary data for studying how mineral composition affects the physical properties of swell-shrink clays in the study area.

A high-grade ore sample from the Cu–Zn–Au Photo Lake volcanogenic massive sulfide deposit (Flin Flon–Snow Lake greenstone belt, Manitoba, Canada) contains a Bi–Ag sulfo-selenide with a composition situated approximately in the middle of the S–Se substitution range (Se ≈ 0.86 apfu and S ≈ 1.05 apfu). These new data, combined with a literature compilation of all publicly available matildite and bohdanowiczite compositional data, reveal a nearly complete range of S–Se substitution between these two minerals, with only the section between BiAgSe0.78S1.18 and BiAgSe0.25S1.75 – about a quarter of the complete S–Se range – not yet documented. These observations suggest that a complete solid-solution series between matildite and bohdanowiczite, as previously suspected, might exist and in a manner similar to the galena–clausthalite complete solid-solution series.

Amphibole and biotite were the principal mafic minerals precipitated during the magmatic and post-magmatic (including hydrothermal) crystallisation stages of coeval metaluminous to slightly peraluminous syenogranites and peralkaline alkali-feldspar granites of the Mandira Granite Massif, in the post-collisional A-type Graciosa Province, S-SE Brazil. Magmatic calcic (ferro-ferri-hornblende and hastingsite) amphiboles occur in the metaluminous syenogranites, whereas calcic (ferro-edenite), sodic–calcic (ferro-ferri-winchite) and sodic (arfvedsonite and riebeckite) amphiboles occur in peralkaline alkali-feldspar granites. Rare earth element (REE) contents decrease from hornblende to winchite and riebeckite, and the partition coefficients indicate increasing compatibility from light rare earth elements (LREE) to heavy rare earth elements (HREE), with a marked preference for the HREE over the LREE in the sodic–calcic and, particularly, the sodic amphiboles. Post-magmatic calcic- (ferro-actinolite) and sodic- (riebeckite) amphiboles are also present in the peralkaline granites. Magmatic biotite (annite) is dominant in syenogranites, whereas post-magmatic annite and late-to post-magmatic annite evolving to siderophyllite occurs in the peralkaline granites. Typical hydrothermal phyllosilicates are chlorite (chamosite) in syenogranites and related greisens, and ferri-stilpnomelane which is present in both peralkaline granites and metaluminous syenogranites. Lithostatic pressure estimates suggest that the main granites were emplaced under pressures of ~93–230 MPa, with close-to-liquidus temperatures varying from ~830°C for syenogranites to ~900°C for the peralkaline granites. The original magmas crystallised mainly under relatively reduced (buffered at ~ –1 ≤ QFM ≤ 0), and more oxidising (somewhat above QFM) environments, respectively. Chlorite, replacing biotite in syenogranites and as the main mineral in the related greisens, permits the temperature of the main hydrothermal event to have taken place between 250 and 272°C. Estimated log (fHF/fHCl) values from biotite compositions vary from ~ –2 to –1 (syenogranites) and ~ –3.5 to –2 (peralkaline granites) and indicate F preference over Cl in the hydrothermal fluid phase.

Chickpea is one of the most important nutritious grain legume crops in the world. There is limited information available on micro- and macro-nutrients in chickpea. Therefore, an effort was made to evaluate a set of 40 chickpea genotypes belonging to all the gene pools including cultivated (Cicer arietinum) as well as wild, Cicer reticulatum from the primary gene pool, Cicer echinospermum from the secondary gene pool and Cicer microphyllum from the tertiary gene pools. Concentration in the seed of the micro- (Zn, Fe, Cu and Mn) and macro-nutrients (Ca, Mg and K) was studied. Substantial variation was observed among different gene pools for the concentration of all the nutrients. The cultivated chickpea exhibited higher seed Cu, Mn, Mg and Ca than wilds indicating positive domestication effect, whereas wild crop relatives were found to have higher levels than cultivated chickpeas for seed Zn, Fe and K concentrations. While comparing desi-type chickpeas with Kabulis, it was revealed that desi types possessed more Zn, Cu, Ca and Mg than Kabulis but reverse was true for seed Fe, Mn and K. Among different desi types (desi brown, desi green and desi black), desi brown types were generally associated with higher mineral nutrient levels. The present study led to the identification of most promising genotypes for different seed micro- and macro-nutrients. These promising lines may serve as genetic resources useful in gene discovery programmes and for alleviating malnutrition or hidden hunger in the developing world.

Morphological and chemical characteristics of 11 warm season pasture weed species were defined. Goldenrod (Solidago altissima L.) was significantly taller and common ragweed (Ambrosia artemisiifolia L.) had the largest canopy diameter of the 11 species studied. Species ranged from 14 to 134 cm in height with canopy diameters of 25 to 70 cm. No direct correlation was found between individual leaf size and total leaf area. Macro- and micromineral content varied widely among species but all values obtained were considered high enough to meet the requirements of ruminant animals. Redroot pigweed (Amaranthus retroflexus L.) and horsenettle (Solanum carolinense L.) contained potentially toxic levels of nitrate. Five of the 11 species contained sufficient crude protein for ruminants and six of the 11 species were more than 50% digestible. Digestible energy values averaged 1.9 Mcal/kg for the 11 weeds evaluated.

This study examined the response of forage crops to composted dairy waste (compost) applied at low rates and investigated effects on soil health. The evenness of spreading compost by commercial machinery was also assessed. An experiment was established on a commercial dairy farm with target rates of compost up to 5 t ha−1 applied to a field containing millet [Echinochloa esculenta (A. Braun) H. Scholz] and Pasja leafy turnip (Brassica hybrid). A pot experiment was also conducted to monitor the response of a legume forage crop (vetch; Vicia sativa L.) on three soils with equivalent rates of compost up to 20 t ha−1 with and without ‘additive blends’ comprising gypsum, lime or other soil treatments. Few significant increases in forage biomass were observed with the application of low rates of compost in either the field or pot experiment. In the field experiment, compost had little impact on crop herbage mineral composition, soil chemical attributes or soil fungal and bacterial biomass. However, small but significant increases were observed in gravimetric water content resulting in up to 22.4 mm of additional plant available water calculated in the surface 0.45 m of soil, 2 years after compost was applied in the field at 6 t ha−1 dried (7.2 t ha−1 undried), compared with the nil control. In the pot experiment, where the soil was homogenized and compost incorporated into the soil prior to sowing, there were significant differences in mineral composition in herbage and in soil. A response in biomass yield to compost was only observed on the sandier and lower fertility soil type, and yields only exceeded that of the conventional fertilizer treatment where rates equivalent to 20 t ha−1 were applied. With few yield responses observed, the justification for applying low rates of compost to forage crops and pastures seems uncertain. Our collective experience from the field and the glasshouse suggests that farmers might increase the response to compost by: (i) increasing compost application rates; (ii) applying it prior to sowing a crop; (iii) incorporating the compost into the soil; (iv) applying only to responsive soil types; (v) growing only responsive crops; and (vi) reducing weed burdens in crops following application. Commercial machinery incorporating a centrifugal twin disc mechanism was shown to deliver double the quantity of compost in the area immediately behind the spreader compared with the edges of the spreading swathe. Spatial variability in the delivery of compost could be reduced but not eliminated by increased overlapping, but this might represent a potential 20% increase in spreading costs.

The main factors affecting the mechanical (and other) properties of bone, including antler, are the proportions of ash (especially Ca and P) and collagen content. However, some trace minerals may also play more important roles than would be expected, given their low levels in bone and antler. One such trace mineral is Cu. Here, we studied the effects of Cu supplementation on the mechanical and structural characteristics, and mineral content of antlers from yearling and adult (4 years of age) red deer fed a balanced diet. Deer (n=35) of different ages (21 yearlings and 14 adults) were studied. A total of 18 stags (11 yearlings and 7 adults) were injected with Cu (0.83 mg Cu/kg BW) every 42 days, whereas the remaining 17 (10 yearlings and 7 adults) were injected with physiological saline solution (control group). The Cu content of serum was analysed at the beginning of the trial and 84 days after the first injection to assess whether the injected Cu was mobilized in blood. Also, the mechanical and structural properties of antlers and the mineral content in their cortical walls were examined at three (yearlings) or four (adults) points along the antler beam. The effect of Cu supplementation was different in yearlings and adults. In yearlings, supplementation increased the Cu content of serum by 28%, but did not affect antler properties. However, in adults, Cu supplementation increased the Cu content of serum by 38% and tended to increase the cortical thickness of antlers (P=0.06). Therefore, we conclude that, even in animals receiving balanced diets, supplementation with Cu could increase antler cortical thickness in adult deer, although not in yearlings. This may improve the trophy value of antlers, as well as having potential implications for bones in elderly humans, should Cu supplementation have similar effects on bones as those observed in antlers.

Mineral concentration levels in cultivated vegetables have received very little concern in the context of biodiversity despite the fact that most vegetables have a rich micronutrient composition. Swiss chard is an important salad crop which is high yielding and rich in minerals, vitamins and phenolic compounds. It is also extremely easy to grow. However, there is a lack of information on the genetic variability of mineral concentration of Swiss chard. Mineral composition diversity of 54 genetically diverse Swiss chard accessions, representative of all Turkish Swiss chard genetic resources, was investigated using multivariate analysis. These traits are useful in evaluating germplasm diversity in the nutritional concentration context and for use in further breeding programmes which will focus on improving mineral concentrations in Swiss chard cultivars. The results displayed significant differences among accessions and remarkably high nutrient contents. The data gathered were analyzed using principal components (PCs) and cluster analysis and revealed five major groupings. The data also observed 74.39% of total variation. The first three PCs accounted for 49.86% of the total variation in the population. Present values provided great variability among accessions and the results demonstrate that it is possible to identify genetic differentiation among Swiss chard accession for some nutritional elements. The genetic resources that exist indicate that potentially important accessions could be used as a gene source due to their high levels of K, Ca, Cu and Zn in breeding programmes.

Cowpea, an indigenous crop to sub-Saharan Africa, is found mainly in the dry savanna regions along with cereals such as millets and sorghum. Cowpea is grown primarily for human consumption of the grains, which are rich in protein, carbohydrates and contain some minerals. The development and deployment of cowpea varieties with higher nutritional value will be of immense benefit to consumers. As a first step in the enhancement of mineral content in cowpea grains, several germplasm lines (1541) of different origins and obtained from the genetic resources unit at IITA were sown in the experimental field in Minjibir, Kano State, Nigeria. The grains were analysed for protein and nine mineral contents. However, in this study, we shall report data on crude protein, Fe, Zn, Ca, Mg, K and P. The data generated from the chemical analysis were subjected to the ‘mixture of normal distributions’ clustering method, which distributed the cowpea lines into nine groups. Groups G7 and G9 contained 174 genotypes and these were characterized by high mineral concentrations. The mean nutritional content values for group G9 were 24.7% for protein, and 58.9, 41.5, 1107, 2132, 15,282 and 5664 mg/kg for Fe, Zn, Ca, Mg, K and P, respectively. On the other hand, the 363 lines making up groups G2, G3 and G6 showed low amounts of nutrients in their grains. Some of the lines in G7 and G9 would be good as parents to use in breeding programmes that aimed at developing nutrient-dense cowpea varieties.

The effects of minerals on casein micelle stability of individual cows' milk, throughout a complete lactation, were investigated. Calcium and calcium ions, magnesium, phosphorus, sodium, potassium and citrate contents were analysed, together with the following physical properties of milk; pH, ethanol stability, rennet clotting time and coagulum firmness. There was an inverse non-linear relationship between free calcium ion concentration and ethanol stability (ES; r=0·84). Rennet coagulation time showed a weaker relationship with free calcium ion concentration (r=0·44) but a stronger relationship with pH (r=0·66). In addition, samples containing higher amounts of free calcium ions produced a firmer gel. Citrate in natural samples acts as a stabilizing factor, as it slightly improves milk stability. Potassium, on the other hand, exhibited a negative correlation, but only with rennet clotting time (r=−0·52). Throughout lactation the average values were; free Ca2+ concentration 1·88 mM, pH 6·63, ES 83·2% and clotting time 13·6 min. The equilibrium relationship between pH and free Ca2+ concentration was investigated by adjusting milk pH from 5·9 to 7·1, using acid and alkali. There was a good inverse linear relationship between pH and log (free Ca2+) for individual milk samples, with a gradient of −0·62 and a standard deviation of 0·042.

Sedimentation Field Flow Fractionation (SdFFF) was combined with Photon Correlation Spectroscopy (PCS), to characterize changes in the structure of the colloidal particles of reconstituted skim milk of diameter >50 nm (aggregates of casein and calcium phosphate known as casein micelles) with the changes in partitioning (with the addition of salt) of calcium (Ca), inorganic phosphate (Pi) and casein between the serum and colloidal phases of the milk. The number weighted particle size distributions are determined. These are well represented by a log-normal distribution. Methods are presented for estimating the relative contributions of scattering and absorbance to the SdFFF detector signal and for taking both into account when analysing SdFFF data. The values found for the effective density of the casein micelles were in good agreement with the literature and ranged from (1·06–1·08 g cm−3) according to the composition of micelles. The changes in the scattering intensity as determined by PCS correlated with the changes in the particle composition. Although the concentrations of colloidal calcium phosphate (CCP) (1·1–3·5 g/kg milk) and micellar casein (18·1–27·2 g/kg milk) varied considerably only small changes in the size distribution of particles >50 nm diameter were observed except for milk to which 30 mmol Pi+10 mmol Ca/kg milk had been added where the particle size distribution shows a swelling of the particles consistent with a lower than expected value for the particle density. These observations suggest that the micelles have the ability to both lose (depleted micelles) and accommodate (enriched micelles) more casein, calcium and inorganic phosphate in their interior, thus confirming the model of the micelles which postulates an open structure allowing freedom of movement of casein and small ions.

Every month 2 samples of the Rhine and 1 sample of the Rhone are analysed for about 20 chemical and physical variables at 7 stations by two monitoring agencies.This paper presents some of our conclusions on the accuracy of these programmes and on the solubility of the calcium/carbonate/sulphate/phosphate system. In total we have analysed 916 data sets ; they were screened for imprecision before being used.At all stations the water is saturated with CaCO3 , but the "apparent" solubility product depends on the pH. The regression line can be described by IPca = 8.73 x 10-15. pH15.667.In both the Rhine and the Rhone an acidification is seen and an increase of the sulphate concentration when going downstream. We have shown that the increase in sulphate concentration is due to the disposal of CaSO4. This addition of sulphate influences the quotient Ca/HCO3. The data fit very well the theoretical regression line Ca/HCO3 = 0,5(SO4) + 0.5.The acidification originates from the mineralization of organic matter. For 6 stations dowstream from the great lakeswe found that the two rivers are saturated with hydroxy-apatite, the -log of the ionic product being 49.9 (Rhine ; σ = 0.6 ;N = 259) and 50.0 (Rhone ; σ = 0.3 ; N = 479). The o-phosphate concentration does not therefore depend on the phosphate loading of the rivers, but on the Ca concentration, the temperature and the pH. This has great influence on the transport of phosphate through the delta's of the two rivers. The disturbance of acidity and buffering capacity influences heavy metal behaviour as well.