Manganese In Copper Research Articles

Enzymatic hydrolysis method for development of low glycemic index rice flour from temperate grown rice (var. Jehlum): Numerical optimization, rheological and spectroscopic characteristics

This study aimed at optimizing process protocols for development of low glycemic index (GI) rice flour (LGIRF) by employing enzymatic hydrolysis method using central composite rotatable design (CCRD). LGIRF was evaluated for pasting, farinographic, spectroscopic and microbiological attributes. Independent variables for optimization included concentrations of α-amylase (0.02–0.12 %), glucoamylase (0.02–0.24 %), as well as the incubation temperature (55–80°C). Resistant starch (RS), glycemic index (GI) and glycemic load (GL) were investigated as response variables. The optimum conditions for development of LGIRF with better quality were- α-amylase concentration of 0.040 %, glucoamylase concentration of 0.070 % and an incubation temperature of 60 °C. The results of mineral analysis revealed significantly (p < 0.05) lower levels of boron, potassium, zinc, phosphorus, magnesium, and manganese in LGIRF, while iron and copper were significantly higher. The viscosity profile as evident from pasting profile and farinographic characteristics of LGIRF were significantly (p < 0.05) lower than native rice flour. 1H NMR and 13C NMR spectroscopic studies showed an increase in flexible starch segments and a decrease in amorphous portion of starch LGIRF, along with chemical shift alterations in carbons 1 and 4. Free fatty acids and total plate count were significantly (p < 0.05) higher in LGIRF although was within limits.

Thermodynamics of Mn in Cu-Mn Melts

The present work aimed to measure the thermodynamic data of manganese in Cu-Mn melts over a broad manganese concentration range, using the equilibrium among the liquid copper/MnO(s)/CO-CO2 gas mixture in the temperature range from 1673 K to 1873 K (1400 °C to 1600 °C). Darken’s quadratic formalism was introduced to correlate the activity coefficient of manganese in copper to composition, and the excess molar Gibbs energy change of mixing of Cu-Mn melts was described satisfactorily by Redlich–Kister type polynomial.

Do the other nutrients except calcium and vitamin D prevent the incidence of osteoporosis

Osteoporosis as a skeletal disorder characterize by compromised bone strength predisposing a person to an increased risk of fracture. All people should be encouraged to take efforts to prevent bone loss and fractures. Nutrition is one of several factors that can be modified to reduce osteoporosis risk. The purpose of this review article is assessment the role of the other nutrients the exception of calcium and vitamin D on bone health and prevention of osteoporosis.The search was undertaken in three databases (PubMed, google scholar and science direct) for publications from 2005 onwards using key words as follows. Initial searches yielded approximately 2467 results. After considering additional exclusion criteria, 33 clinical trial and meta- analysis papers remained.According to investigations, high intake of dietary protein increase bone resorption and calcium excretion and low protein intake can prevent calcium absorption and decrease strength and bone mass. Omega-3 supplementation also can decrease bone resorption and α-linleic acid (for men and women) and arashidonic acid (in men) and isoflavones can significantly diminish the risk of hip fracture. Adequate intake of some nutrients like zinc, vitamin A, boron and manganese in bone formation and copper, fluoride and strontium in bone mineralization have positive effects. However, high intake of vitamin A and fluoride result in hip fracture incretion. Vitamin K (in form of K 2 ) along with calcium and vitamin D induce bone fracture decrease. If intake of phosphate, iron and sodium be more than the recommended values, they may present negative effects on bone mineralization.In conclusion, risk of osteoporosis incidence may be diminished with an adequate and balanced diet containing variety of foods to meet needs and a healthy lifestyle. Nutrition education and training the other preventive factors should be carrying out in childhood to achieve the peak bone mass in youth and aging.

Interdiffusion in the f.c.c. Phase of Cu-Mn Binary Alloys

Interdiffusion coefficients are calculated in the Cu-Mn binary system from 450 to 925 °C. Starting from the diffusion couples between pure Cu and Mn, the solubility limit of the manganese in copper is determined and the interdiffusion characteristics in the f.c.c. solid solution of Cu-Mn alloys are analysed. The interdiffusion coefficients in this binary system are calculated by the den Broeder method. The interdiffusion coefficients are strongly dependent on the composition: their values lie between approximately 10−14 and 4 × 10−9 cm2 s in this temperature range. The Vignes and Birchenall method is used to determine the impurity diffusion coefficients of manganese in pure copper. These coefficients are compared with the tracer diffusion coefficients of Mn54 in copper from the literature. Activation energies, which lie from 155 to 180 kJ/mol, are of a vacancy controlled diffusion mechanism.

Activity Coefficient of Manganese in Copper

Activity Coefficient of Manganese in Copper

Trace metals in bulk freefall and roof intercepted rainwater at Ile-Ife, Southwest Nigeria

Samples of bulk freefall and roof-intercepted rainwater collected over five roof types (viz: Iron–Zinc sheets, Aluminum sheets, Asbestos sheets, Slate tiles, and Thatch) at Ile-Ife (SW Nigeria) were analysed for nine trace metals (aluminum, cadmium, chromium, copper, iron, lead, manganese, nickel, and zinc) using atomic absorption spectrophotometry (AAS). The mass concentrations and percent detection of the trace metals were generally higher in roof-intercepted samples than in the freefall samples. The ranking order of the mean concentrations of the metals in freefall samples (Al > Cr > Fe > Zn > Pb > Mn > Ni > Cu > Cd) is indicative of an atmospheric environment greatly influenced by heavy vehicular emissions and remobilized suspended particulate matter of soil origin. Mean metal enrichment of samples over the different roofs was in the order of Iron–Zinc > Aluminum > Thatch > Asbestos > Slate roof. Each roof sample type (except Slate samples) was characterized by relatively high enrichment of one or two metals. These include the high enrichment of zinc and iron in Iron–Zinc roof samples, cadmium and manganese in Aluminum roof samples, copper and manganese in Thatch roof samples and cadmium in Asbestos roof samples. The metal concentrations of roof-intercepted rainwater were lower than those of neighboring surface water, packaged table water, and vegetation-intercepted rainwater in the same environment. The metal levels in all the rainwater sources occurred within the allowable guide levels for most public and domestic applications.

Structural characterisation of copper-containing manganese oxide octahedral molecular sieve (Cu-OMS-2) materials by X-ray absorption spectroscopy and cyclic voltammetry

X-ray absorption spectroscopy (X-ray absorption near-edge structure including pre-edge features and extended X-ray absorption fine structure studies) and cyclic voltammetry analyses were used to study copper substituted manganese oxide octahedral molecular sieve (Cu-OMS) microporous materials. The results from the X-ray absorption spectroscopy study have been interpreted in terms of possible locations of Cu 2+ ions in the microporous zeotypic OMS-2 structure. According to the synthetic route, the Cu 2+ ions are expected to interact with the surface atoms, and do not replace any of the framework atoms. The results are consistent with copper interacting with lattice oxygen and manganese atoms, and are therefore, also consistent with copper being sited within the channels of OMS-2. Qualitative pre-edge studies on manganese in copper doped OMS-2 show octahedral Mn 4+. The latter confirmed by cyclic voltammetric analyses giving similar voltammograms as for the manganese dioxide and non-mobility for Mn 2+ in the OMS-2 material.

Excess chromium alters uptake and translocation of certain nutrients in citrullus

Citrullus plants were grown in refined sand with varying levels of chromium to determine their tolerance limit to excess chromium. The plants were maintained in control nutrient solution for 24 days and on the 25th day chromium as dichromate was added at 0.05, 0.1, 0.2, 0.3 and 0.4 mM. A control set of plants was grown in the same nutrient solution without chromium. At chromium levels >0.2 mM plants showed growth depression, with chlorosis and loss of turgor of middle leaves. Affected leaves had narrow lamina; tendrils were thin, short and did not have coiling property. Later chlorosis became severe and changed to necrosis in patches. Petiole along with lamina became wilted, rugged and hung down due to complete loss of water. At lower chromium concentration, (0.05, 0.1 and 0.2 mM) only depression in growth was observed. With increase in chromium concentration of nutrient solution accumulation of chromium in different parts of Citrullus was increased. Increase in concentrations of phosphorus, manganese and decrease in iron, copper, zinc and sulphur were observed in leaves. Toxicity of chromium was greater at 0.2–0.4 mM, compared to lower concentrations. Threshold of toxicity and toxicity of Cr in old leaves were, respectively, 0.9 and 3.9 μg g −1 dry matter of citrullus.

Simultaneous determination of manganese, iron and cobalt in copper with a multi-element graphite furnace atomic absorption spectrometer

A simple method was developed for the determination of trace metals (Mn, Fe and Co) in copper simultaneously using a multi-element graphite furnace atomic absorption spectrometer (Perkin-Elmer SIMAA6000) equipped with a transversely heated graphite atomizer. Copper was dissolved in nitric acid before analysis using a microwave digestion system. Pd(NO 3) 2 with the special gas (5% H 2 in Ar) was used as the chemical modifier. The accuracy of the method was confirmed by the analysis of certified reference copper (CRM#075). The interferences were removed effectively, so that a calibration curve method based on simple aqueous standards could be used. The analyzed values were in the range of 96.6% (Mn) to 113% (Co) of the certified values. The relative standard deviations for the simultaneous determination of Mn (6.5 μg/l), Fe(18 μg/l) and Co(5 μg/l) in solution from copper are 2.4–3.5% and the detection limits were 0.17 μg/g for Mn, 0.50 μg/g for Fe and 0.30 μg/g for Co.

Manganese and Phosphorus Equilibria between Liquid Copper and MnO-P2O5 Slag.

The liquid copper alloys containing 0.2-1.0 mass% Mn and 0.03-0.5 mass% P were equilibrated with MnO saturated and unsaturated MnO-P2O5 slags in a molybdenum crucible under a flowing CO2/CO or CO2/H2 atmosphere in the temperature range of 1523 to 1673 K. Manganese-phosphorus and manganese-manganese interaction parameters in liquid copper were found at 1623 K as follows:ePMn= -0.010 eMnP= -0.021 eMnMn= 0.027These values were examined by considering the relationships among oxygen partial pressure, the activities of manganese and phosphorus in liquid copper. The standard free energy changes for the reduction of solid MnO, MnO(s)=Mn+1/2 O2(g), and the dissolution of pure liquid manganese in liquid copper, Mn (l)=Mn, were determined as a function of temperature. The activities of MnO and P2O5 in MnO-P2O5 slags were measured at 1573 K as a function of the composition. The temperature dependence equation of the P2O5 activity was also derived in the MnO saturated condition. On the basis of the present results, examination was done concerning phosphorus and manganese equilibria between hot metal and the MnO-P2O5 slag.

Reheating of a Laser-Produced Plasma by a Second Pulse Laser

Focused radiation of a Nd:YAG laser was used for ablation and production of free sample atoms from electrically conducting and nonconducting solids for analytical purposes. The microplasmas were generated in an argon buffer gas atmosphere at reduced pressure. In order to increase the intensities of analyte lines the microplasmas were reheated by a second Nd:YAG laser after the process of atomization was completed. It is demonstrated for aluminum and manganese in glass and steel samples and for magnesium and manganese in glass, copper, and aluminum that by internal standardization a common calibration curve can be obtained.

Manganese, Copper, Zinc, and Iron Concentrations and Subcellular Distribution in Two Types of Skeletal Muscle

To clarify trace element distribution in red and white muscle, and to verify two populations of muscle mitochondria, the iron, zinc, copper, and manganese concentrations of whole muscle and their subcellular fractions were determined. The iron, zinc, copper, and manganese concentrations of red muscle were 1.83, 4.31, 2.05, and 1.67 times higher than those of white muscle, respectively. In skeletal muscle subcellular distribution or iron, zinc, and copper were entirely different and that of manganese was relatively similar as compared with those in liver reported previously. The pattern of mineral distribution in all fractions of red muscle was similar to that of white muscle, but their concentrations in some fractions were different between red and white muscle, e.g., iron, zinc, and manganese in supernatant fraction and copper in nuclear and microsomal fractions. The difference between subsarcolemmal and interfibrillar mitochondria were ascertained by the distribution of trace elements.

Tissue distribution of heavy metals in Dall's porpoise in the northwestern Pacific

Tissue distribution of heavy metals (iron, manganese, zinc, copper, lead, nickel, cadmium, and mercury) were investigated in the adult male, female, and foetal Dall's porpoises collected by salmon gill net in the north-western North Pacific. Determination of the metals was carried out by atomic absorption spectrophotometry. The heavy metal concentrations in the adults were generally high in liver, and low in blubber. Some metals showed organ- and metal-specific accumulations: zinc, nickel, and lead exhibited high concentrations in skin and bone; the cadmium concentration was relatively high in pancreas and adrenal and the highest concentration was observed in kidney. Similar tissue distribution patterns of metals were also found in the foetus, but the concentrations of manganese in bone, testis, and copper in liver, were relatively high compared with those in the adults. The concentration of cadmium in the foetus was very low, indicating that transplacental transfer of cadmium is negligible. The majority of the metal burdens in the body was in the muscle, liver and bone, whereas relatively high burden of cadmium was in the kidney. Based on these results, the suitability of tissues of a porpoise for ecological and physiological comparisons is discussed.

Electrothermal atomic absorption determination of arsenic, antimony, bismuth, manganese, nickel, selenium, tellurium, and chromium in pure copper

Traces of As, Bi, Cr, Mn, Ni, Sb, Se and Te in pure copper were determined by means of electrothermal atomic absorption spectrometry using continuum source background correction and computer signal processing. The effect of the copper matrix on the atomic absorption signals close to the noise level and on sensitivity are studied. The limits of detection were determined in the presence of 50 μg of copper.

Spin coupling between magnetic impurities in metals.

The spin scattering of conduction electrons by the local moments of transition-metal ions dissolved in metals, e.g., manganese in copper or silver, comes from the s-d mixing interaction. The characteristic energy and angular dependence of this scattering has a marked influence on the spin coupling between two local moments. We have derived expressions for this coupling due to s-d mixing. However, rather than evaluate the coupling itself, its envelope is much more relevant when one is interested in the range of the coupling. We have determined the envelope function by using only single-ion parameters. We find that in the range Rl15a, the decay of the spin coupling is much slower than that of the Rudermen-Kittel-Kasuya-Yosida interaction, i.e., 1/${R}^{3}$. This difference comes from the energy and angular dependence of the scattering which have been taken into account in the calculation. The calculations are made both with and without mean-free-path effects. We find that the preasymptotic corrections are far more important than mean-free-path effects for dilute systems. We have also calculated spin-interaction constants. Our results are very close to the values obtained from the low-field magnetization measurements.

Grandeurs thermodynamiques de formation des solutions solides binaires diluées CuM lorsque m décrit la première longue période

The enthalpies of mixing of binary dilute solutions of the solutes manganese, iron, cobalt, nickel, gallium and germanium in copper were measured by liquid tin calorimetry. The excess free enthalpies of binary dilute solutions of the solutes titanium, chromium, manganese, iron, cobalt, nickel, gallium and germanium in copper were determined by solid cell e.m.f. measurements. The experimental results for chromium, manganese, iron and cobalt in copper are compared with data calculated using phase diagrams. This method is also used to calculate data for CuV. In the final discussion enthalpies of mixing and excess free enthalpies are compared. The experimental results are discussed in relation to the theoretical calculations of Parlebas.

Diffusion of vanadium, chromium, and manganese in copper

The diffusion coefficients of vanadium, chromium and manaanese in copper have been determined by the residual activity method with radioactive tracers V48, Cr51 and Mn54 in the temperature ranges between 955 and 1342 K, between 999 and 1338 K and between 971 and 1253 K, respectively. The temperature dependence of the diffusion coefficients is expressed by the following Arrhenius equations along with the probable errors:DV/Cu = (2.48-0.44+0.53) x 10−4 exp [-(215 ± 2) kJ mol−1/RT] m2 per s,DCr/Cu = (0.337-0.090+0.124) x 10−4 exp [-(195 ± 3) kJ mol−1/RT] m2 per s,DMn/Cu = (1.02-0.18+0.22) x 10−4 exp [-(200 ± 2) kJ mol−1/RT] m2 per s.

Resistance of thin films of copper and copper alloys deposited at temperatures less than 10 K

An apparatus has been developed for the deposition of evaporated films at less than 10 K and the subsequent measurement of resistance of the fihns between 1.5 and 300 K. In this paper results are given for the annealing on the films with emphasis on the sharp transition temperature at which irreversible annealing commences. This is 15 +_ 1 K for Cu fihns and 31 +_ 2 K for alloys of manganese in copper.

Manganese in copper based alloys

Project: Provide white alloys having reduced metal cost, improved hot workability, similar mechanical properties, and cold working characteristics comparable to the nickel silvers

Temperature dependence of localized moments in dilute (Cu)Mn alloys

Magnetic susceptibility data on very dilute alloys of manganese in copper are reported from room temperature up to 770°K. Applications of Scalapino's theory would indicate a Kondo temperature near 6°K and S≈ 5 2 , however, current theories do not adequately describe the experimental data over a wide temperature range.