Effects of Dietary Copper Level on Blood and Tissue Copper Contents in Geese

In order to study the effect of dietary copper level on blood and tissue copper contents in geese, one-week Sichuan white geese were randomly divided in- to four groups, and the geese in the first, second, third and fourth groups were fed with diet with copper levels of 39.55, 127.60, 194.75 and 255.22 mg/kg, respective- ly. At the ages of 4, 6, 8, 10 and 12 weeks, the contents of copper in blood, liver, chest muscle and subcutaneous fat of the geese were determined. The effects of dietary copper level, age and sex on the blood and tissue copper contents of geese were analyzed by multivariate analysis of variance. The results showed that the di- etary copper level showed no significant effects on the blood and liver copper con- tents of geese （P〉0.05）; the chest muscle copper content of geese in the second group was significantly higher than that in the first group （P〈0.05）; the subcuta- neous fat copper content of geese in the fourth group was significantly higher than those in the other three groups （P〈0.01）; the age had significant effects on the blood, liver, chest muscle and subcutaneous fat copper contents of geese （P〈0.01）; and the sex showed no significant effects on the blood and tissue copper contents of geese （P〉0.05）.

The Change of Copper Contents and Its Clinical Significance in Patients with Liver Cirrhosis and Hepatocarcinoma

Copper contents(CU) in bodies and serum cerulopasmin(Cp) were assayed in patients with liver cirrhosis(LC) and hepatocarcinoma(HCC) with atomic absorption and other methods.

Rapid vision-based system for secondary copper content estimation

A vision-based color analysis system was developed for rapid estimation of copper content in the secondary copper smelting process. Firstly, cross section images of secondary copper samples were captured by the designed vision system. After the preprocessing and segmenting procedures, the images were selected according to their grayscale standard deviations of pixels and percentages of edge pixels in the luminance component. The selected images were then used to extract the information of the improved color vector angles, from which the copper content estimation model was developed based on the least squares support vector regression (LSSVR) method. For comparison, three additional LSSVR models, namely, only with sample selection, only with improved color vector angle, without sample selection or improved color vector angle, were developed. In addition, two exponential models, namely, with sample selection, without sample selection, were developed. Experimental results indicate that the proposed method is more effective for improving the copper content estimation accuracy, particularly when the sample size is small.

Study on the Mechanical Properties of Ni-Ti-Cu Shape Memory Alloy Considering Different Cu Contents

By adding copper to increase the performance,the Ni-Ti-Cu Shape Memory Alloy(SMA),has been widely used in the field of engineering in recent years.A thermodynamic constitutive model for Ni-Ti-Cu SMA considering different copper contents is established in this work.Numerical results for two different copper contents,as examples,are compared with the experimental results to verify the accuracy of the theoretical work.Based on the verified constitutive model,the effects of different copper content on the mechanical properties of Ni-Ti-Cu SMA and the tensile and compressive asymmetric properties of Ni-Ti-Cu SMA are finally discussed,respectively.

Bifunctionality of Cu/ZnO catalysts for alcohol-assisted low-temperature methanol synthesis from syngas:Effect of copper content

Alcohol-assisted low-temperature methanol synthesis was conducted over Cu/ZnO;catalysts while varying the copper content（X）. Unlike conventional methanol synthesis, ethanol acted as both solvent and reaction intermediate in this reaction, creating a different reaction pathway. The formation of crystalline phases and characteristic morphology of the co-precipitated precursors during the co-precipitation step were important factors in obtaining an efficient Cu/ZnO catalyst with a high dispersion of metallic copper,which is one of the main active sites for methanol synthesis. The acidic properties of the Cu/ZnO catalyst were also revealed as important factors, since alcohol esterification is considered the rate-limiting step in alcohol-assisted low-temperature methanol synthesis. As a consequence, bifunctionality of the Cu/ZnO catalyst such as metallic copper and acidic properties was required for this reaction. In this respect, the copper content（X） strongly affected the catalytic activity of the Cu/ZnO;catalysts, and accordingly, the Cu/ZnO;.5 catalyst with a high copper dispersion and sufficient acid sites exhibited the best catalytic performance in this reaction.

Investigation on the Copper Content of Matte Smelting Slag in Peirce-Smith Converter

The copper contents and its existing forms in the slags during the slag-making stage of Peirce-Smith converters in Guixi Smelter, Jiangxi Province, China have been investigated. The investigation was based on plant trials with the corresponding thermodynamic calculations and kinetic considerations. From the plant data, the total copper content in the slags was in the range of 2% to 8% (mass fraction). The mechanical entrainment of matte drops has been found to be the main cause of the copper loss. The suspension index, defined as the ratio of the mass fraction of copper in suspended matte drops in the slag to that in bulk of the matte phase, has been adopted to quantify the matte entrainment. The values of this parameter estimated in this work have been found mainly within a range of 2.5%-8.0%. The Fe3O4 content in the slag has been estimated to be the most important factor, among others, influencing the separation of slag with matte and, consequently, the copper loss from the slag.

Effects of Varying Copper Content on the Microstructure and Mechanical Properties of FeCoNiCu_(x)

Five sets of high entropy alloys(HEAs)FeCoNiCu_(x)(x=0.5,1.0,1.5,2.0,2.5)were produced by vacuum induction smelting.The effects of Cu content on the microstructure and mechanical properties of the alloys were interrogated by X-ray diffractometer(XRD),field scanning electron microscope(FESEM)and tensile mechanical test.The result shows that the HEAs form single FCC solid solution phase.With the increase of Cu content,the diffraction peak first deviated to the right and then shifted to the left.The alloys changed from equiaxed crystal structure to refined dendritic crystal structure,as Cu content increased.A large number of Cu atoms are isolated in the inter-crystalline region.The tensile mechanical tests show that with the increase of Cu content,the ultimate tensile strength first increased and then decreased.When x is 2.0,the ultimate tensile strength reaches a maximum of 473 MPa,the percent elongation is 43.0%,and the fracture presents ductile behaviour.

Effects of copper content on the shell characteristics of hollow steel spheres manufactured using an advanced powder metallurgy technique

Metallic hollow spheres are used as base materials in the manufacture of hollow sphere structures and metallic foams. In this study, steel hollow spheres were successfully manufactured using an advanced powder metallurgy technique. The spheres＇ shells were characterized by optical microscopy in conjunction with microstructural image analysis software, scanning electron microscopy（SEM）, energy-dispersive X-ray spectroscopy（EDX）, and X-ray diffraction（XRD）. The microscopic evaluations revealed that the shells consist of sintered iron powder, sintered copper powder, sodium silicate, and porosity regions. In addition, the effects of copper content on various parameters such as shell defects, microcracks, thickness, and porosities were investigated. The results indicated that increasing the copper content results in decreases in the surface fraction of shell porosities and the number of microcracks and an increase in shell thickness.

Dietary copper requirement of broilers fed a corn-soybean meal diet during 22—42 d of age

This research was to assess the dietary copper(Cu)requirement of broiler chickens fed a practical cornsoybean meal diet during 22—42 d of age.A total of 288 numbered Arbor Acres male broilers at 22 d of age were randomly allotted 6 treatments with 8 replicate cages(6 broilers per cage)per treatment.Broilers were fed a Cu-unsupplemented corn-soybean meal basal diet(control,containing 7.36 mg Cu/kg)or the basal diet added with 3,6,9,12,or 15 mg Cu/kg from CuSO_(4)·5H_(2)O for 21 d.Quadratic,asymptotic and broken-line models were fitted and the best fitted models were selected to determine dietary Cu requirements.The results revealed that the contents of Cu in serum and liver,m RNA expression levels of Cu-and zinc-containing superoxide dismutase(CuZnSOD)in liver and monoamine oxidase b(MAO B)in heart,as well as protein expression level of CuZnSOD in liver were affected(P<0.05)by supplemental Cu levels,and the above indices varied linearly and quadratically(P<0.05)with increasing Cu levels.Dietary Cu requirements assessed according to the best fitted broken-line models(P<0.05)of the above indexes were 10.45—13.81 mg/kg.It was concluded that mRNA expression levels of CuZnSOD in liver and MAO B in heart,as well as liver CuZnSOD protein expression level were new specific sensitive biomarkers for estimating dietary Cu requirements,and the dietary Cu requirement was recommended to be 14 mg/kg to support Cu metabolic needs related to key Cucontaining enzymes in broilers fed the corn-soybean meal diet during 22—42 d of age,which was higher than the dietary Cu requirement(8 mg/kg)for broilers at the corresponding stage suggested by the Chinese Feeding Standard of Chicken.

Quench sensitivity of novel Al-Zn-Mg-Cu alloys containing different Cu contents

The effect of copper content on quench sensitivity in novel Al-Zn-Mg-Cu alloys containing high zinc content was investigated by Jominy end quench test.Electrical conductivity and hardness test,temperature collecting,and transmission electron microscopy(TEM)technique were adopted for the properties and microstructure characterization of three alloys with different copper contents.The results indicate that the electrical conductivity of all three alloys increases with the increase of distance from the quenched end,while the hardness shows an opposite trend.If the dropping of 10%hardness is defined as the critical evaluation standard of quenching,the depth of quenched layer of AlloysⅠ,Ⅱ,andⅢare 70,55,and 40 mm,respectively.The precipitation behavior on grain boundaries of three alloys is similar except for a little difference in size,while the size of precipitates in grains of AlloyⅢwith higher copper content is larger than those of the other two alloys at the same location.Considering all results,the stability of the supersaturated solid solution of AlloyⅢis lower than those of the other two alloys,meaning that AlloyⅢshows the highest quench sensitivity.Higher copper content leads to higher quench sensitivity in novel Al-Zn-Mg-Cu alloys with the same content of magnesium,zinc,and other trace elements.