Optimal dietary copper requirements and relative bioavailability for weanling pigs fed either copper proteinate or tribasic copper chloride

Background: The objective of this study was to determine the effects of supplementing Cu on growth performance, Cu metabolism and Cu-related enzyme activities of weanling pigs fed diets with two different Cu sources, and to estimate optimal Cu requirements and relative bioavailability from these two sources for pigs.Methods: Weanling pigs were allocated to 14 treatments arranged factorially, including 6 added Cu levels(5, 10,20, 40, 80, 160 mg/kg), and 2 mineral sources(tribasic Cu chloride, TBCC and copper proteinate, Cu Pro), as well as one negative control(0 mg/kg added Cu level) and one maximum allowed level treatment(200 mg/kg TBCC) for the entire 38-d experiment. Growth performance, mineral status and enzyme activities were measured at the end of this study.Results: Increasing levels of Cu showed linear and quadratic responses(P < 0.01) for final BW, ADG and FCR regardless of the sources. Supplementation with TBCC(> 80 mg/kg) and Cu Pro(> 20 mg/kg) significantly decreased(P < 0.05) diarrhea incidence of weanling pigs. There were linear and quadratic increases(P < 0.01) in bile, hepatic,and intestinal Cu concentrations, fecal Cu contents, and plasma enzyme activities(alkaline phosphatase,ceruloplasmin, Cu, Zn-Superoxide dismutase(Cu/Zn SOD), and glutathione peroxidase), whereas plasma malondialdehyde decreased(P < 0.01) linearly and quadratically as dietary Cu level increased. Similarly, pigs fed Cu Pro absorbed and retained more Cu and excreted less Cu than those fed TBCC when supplemented 80 mg/kg and above. Optimal dietary Cu requirements for pigs from 28 to 66 d of age estimated based on fitted broken-line models(P < 0.05) of bile Cu, plasma Cu/Zn SOD and growth performance were 93–140 mg/kg from TBCC, and 63–98 mg/kg from Cu Pro accordingly. According to slope ratios from multiple linear regression, the bioavailability value of Cu Pro relative to TBCC(100%) was 156–263%(P < 0.01).Conclusion: The findings indicated that Cu recommendation from current NRC(5–6 mg/kg) was not sufficient to meet the high requirement of weanling pigs. Cu from Cu Pro was significantly more bioavailable to weanling pigs than TBCC in stimulating growth and enzyme activities, decreasing diarrhea frequency and fecal Cu contents to the environment.

Dissolution kinetics of low grade complex copper ore in ammonia-ammonium chloride solution

The leaching kinetics of Tang-dan refractory low grade complex copper ore was investigated in ammonia-ammonium chloride solution.The concentration of ammonia and ammonium chloride,the ore particle size,the solid-to-liquid ratio and the temperature were chosen as parameters in the experiments.The results show that temperature,concentration of ammonia and ammonium chloride have favorable influence on the leaching rate of copper oxide ores.But,leaching rate decreases with increasing particle size and solid-to-liquid ratio.The leaching process is controlled by the diffusion of the lixiviant and the activation energy is determined to be 23.279 kJ/mol.An equation was also proposed to describe the leaching kinetics.

Synthesis,Crystal Structure and Luminescent Property of a New Copper(Ⅰ) Iodide Complex Based on 3,5-Dimethyl-4-amino-triazole

The title compound,[Cu4I4（C4H8N4）4],has been synthesized and characterized by single-crystal X-ray diffraction analysis.It crystallizes in monoclinic,space group Pbca,with a=18.1851（10）,b=9.3697（5）,c=19.8034（10）A,V=3374.3（3）A^3,C16H32Cu4I4N16,Mr=1210.34,Z=4,Dc=2.383 g/cm^3,μ=6.183 mm^-1,F（000）=2272,S=1.032,the final R=0.0309 and wR=0.1180 for 3854 observer reflections（I〉2σ（I））.The structure of the title compound consists of tetranuclear copper cluster units bridged by the halogen atoms with the 3,5-dimethyl-4-aminotriazole ligands coordinated to the metal ions through the triazole nitrogen atoms.The luminescent property of 1 was also studied.

Kinetics of the Chlorination of Copper （I） Sulphide by Calcium Chloride in the Presence of Oxygen

The chemism of the chlorination of copper （I） sulphide by calcium chloride in the presence of oxygen has been determined based on the thermodynamic analysis in the Cu2S-CaCl2-O2 system as well as characterization of used raw materials and obtained products. The influence of temperature （from 473 to 773 K）, time （from 2 to 120 min）, oxygen flow （from 20 to 100 L/h） and calcium chloride quantity （from 5 to 40%） on the chlorination degree has been investigated. Kinetic analysis and the activation energy values of 20.89 kJ/mol showed that the chlorination of copper （I） sulphide by calcium chloride in the presence of oxygen is diffusion controlled.

Self-assembled monolayer modified copper(Ⅰ) iodide hole transport layer for efficient polymer solar cells

The morphology of the copper iodide （CuI） film as an inorganic p-type material has an important influence on enhancing the performance of polymer solar cells （PSCs）. A self-assembled monolayer of 3-aminopropanoic acid （C3-SAM） was used on the surface of indium tin oxide （ITO） before depositing the CuI films. Consequently, a well-distributed and smooth CuI film was formed with pinhole free and complete surface coverage. The root mean square of the corresponding CuI film was reduced from 3.63 nm for ITO/CuI to 0.77 nm. As a result, the average power conversion efficiency （PCE） of PSCs with the device structure of ITO/C3-SAM/CuI/P3HT：PC61BM/ZnO/Al increased significantly from 2.55% （best 2.66%） to 3.04% （best 3.20%） after C3-SAM treatment. This work provides an effective strategy to control the morphology of CuI films through interracial modification and promotes its application in efficient PSCs.

Deprotection of t-Butyldimethylsiloxy (TBDMS) Protecting Group with Catalytic Copper (II) Chloride Dihydrate

t-Butyldimethylsilyl (TBDMS) ether can be cleaved upon refluxing in acetone/H2O (95 : 5) in the presence of a catalytic amount of copper (II) chloride dihydrate (5 mmol %).

Preparation of Pure Copper Powder from Acidic Copper Chloride Waste Etchant

The method for the recycling of copper from copper chloride solution was developed. This process consists of extraction of copper, purification and particle size reduction. In the first step, reductive metal scraps were added to acidic copper chloride waste enchants produced in the PCB industry to obtain copper powder. Composition analysis showed that this powder contained impurities such as Fe, Ni, and water. So, drying and purification were carried out by using microwave and a centrifugal separator. Thereby the copper powder had a purity of higher than 99% and spherical form in morphology. The copper powder size was decreased by ball milling.

A New Copper(Ⅰ) Iodide Coordination Polymer Incorporating Cu_2I_2 Double-stranded Stair: Synthesis, Crystal Structure and Luminescent Property

A new coordination compound, [（CuI）（Btd）]n （1, Btd = 2,1,3-benzothiadiazole）, was obtained at room temperature by the reaction of 2,1,3-benzothiadiazole with CuI and KI saturated aqueous solution. It was characterized by elemental analysis, IR spectroscopy, single-crystal X-ray diffraction analysis and photoluminescence. The complex crystallizes in the triclinic Pi space group, with a = 4.1620（6）, b = 10.4590（15）, c = 10.5052（15） A, a = 69.310（2）, β = 83.608（2）, γ = 78.873（2）°, V = 419.30（10） A3, Z = 2, C6H4N2SCuI, Mr = 326.61, Dc = 2.587 g/cm^3, F（000） = 304 and/^（MoKa） = 6.464 mm-1. The final R = 0.0418 and wR = 0.0936 for 1451 observed reflections with 1 〉 2σ（I） and R = 0.0422 and wR = 0.0939 for all data. In the complex, the Cu atoms are coordinated by one nitrogen atom and three iodine atoms to form a double-stranded stair, and such stairs are further linked to build a 2D framework via C-H…I interactions.

Real-solution stability diagrams for copper-ammonia-chloride-water system

A comprehensive thermodynamic model, which combined the Helgeson Kirkham-Flowers （HKF） equation of state for standard-state thermodynamic properties of all species with realistic activity coefficient model developed by BROMLEY, was used to calculate the thermodynamic equilibrium, and a graphical method was developed to construct predominance existence diagrams （PED） for copper-ammonia-chloride in the presence of realistically modeled aqueous solutions. The existence of the different predominant chemical species for Cu（lI） predicted by the diagrams was corroborated by spectrophotometrical studies and X-ray diffractometry. The simulated and experimental results indicate that the predominance of a given species in solution strongly depends on the pH value in this system. More quantitative information on real copper hydrometallurgy in the presence of ammonia and chloride can be obtained from these diagrams compared with the conventional predominance existence diagrams.

Oxidation of 2,2'-Dihydroxy-3,3'-di-tert-buty-5,5'-dimethoxyl-biphenyl to 3,3'-Di-tert-butylbiphenyl-2,5,2',5'-diquinone with Copper(Ⅱ)Chloride as Catalyst:Synthesis,Structure and Spectral Properties of Diquinone

Use of free air as oxidant and copper（II）chloride as catalyst,3,3＇-di-tert-butylbi-phenyl-2,5,2＇,5＇-diquinone（BBDQ）was prepared via catalytic oxidation of 2,2＇-dihydroxy-3,3＇-di-tert-butyl-5,5＇-dimethoxy-biphenyl（di-BHA）.The yield of reaction attained 95% and the selectivity for BBDQ was 100%.The single-crystal X-ray diffraction analysis reveals that the dihedral angle between two rings（benzene rings for di-BHA and quinone rings for BBDQ）changes from 89.8 to 45.3o,indicating the steric hindrance effects of methyl disappear in the oxidation process.The crystal structures of di-BHA and BBDQ are further confirmed by their spectral characterizations.The probable mechanism for this oxidation process is also discussed.

Multi-stimuli-responsive aggregation-induced emission copper iodide cluster

Stimuli-responsive luminescent materials have attracted significant attention in the development of smart photoactive materials for both fundamental research and technological applications.In this work,a new copper iodide cluster(1)with aggregationinduced emission(AIE)characteristic,was obtained combining Cu_(4)I_(4) core with rhodamine B derivative ligand.1 has reversible and distinct multi-stimuli-responsive luminescence for external temperature,volatile organic compound,and mechanical force.Significantly,1 exhibited unusual large blue shift(84 nm)after being ground,which originated from the change of intermolecular interactions.Moreover,1 exhibits high oxygen quenching efficiency for 82.2% at 1 bar.Mechanistic studies showed that the multi-stimuli-responsive luminescence properties of 1 can be attributed to the regulation of cluster-centered luminescence process,metal-to-ligand charge transfer process,halide-to-metal charge transfer luminescence process and aggregationinduced barrier to oxygen process.This work not only reports an AIE copper iodide cluster,but also provides a new strategy to develop multi-stimuli-responsive luminescence materials.

Evaluation Research on Applicability of Rapid Iodide Migration Test

The applicability of the rapid iodide migration test was systematically studied. Comparative experimental tests of different test conditions, including several external voltages, test durations, concrete ages and mixing proportions, were carried out to make clear the transport behaviors of iodide under parallel electric fields. Numerical simulations were also done using the finite element method to found the correlation between chloride and iodide transport behaviors. The test and numerical results show that the chloride transport behaviors of RIM and RCM tests have a good correlation under the several conditions used in the present paper. Moreover, the influence of external conditions （external voltages, test durations） on the test results is small. Thus, it can be concluded that the RIM method is available to determine the chloride penetration resistance of the chloride-eroded structural concrete.

CATHODIC REDUCTION OF METAL-CHLORIDE COORDINATION IONS

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Disposal of cuprous chloride waste water

The waste water system generated in the process of production of cuprous chloride was studied.The existing forms of copper in the system and the influence of temperature and pH on the existing forms of copper ion were analyzed and determined through calculating the coefficients of copper complex distribution.In the waste water system,the main forms of copper are CuSO4, Cu2 +,CuCl + ,CuCl, 2-and2- 3 CuCl.Temperature has little influence on the distribution coefficient of Cu(Ⅱ),but has significant influence on distribution coefficient of Cu(Ⅰ).With the increase of temperature,the distribution coefficient ofCuCl, 2-increases significantly while the distribution coefficient of2- 3 CuCl decreases.The pH has nearly no influence on the distribution coefficients of various Cu(Ⅰ)-compounds,but has sizable influence on the distribution coefficients of Cu(Ⅱ)-compounds.With the increase of pH,the distribution coefficient of CuSO4(aq)increases while the distribution coefficients of Cu 2+ and CuCl + decrease.According to these results,the anion resin of 201×7 OH-and the cation resin of 732 Na were chosen to dispose the waste water solution of cuprous chloride.Finally,97.9%copper in the waste water is recovered.

改性铜基催化剂催化乙炔氢氯化反应的研究

利用浸渍法将2,5-二甲基吡嗪(DMP)和氯化铜负载到活性炭上,在140℃、乙炔体积空速为50 h-1、氯化氢与乙炔摩尔比为1.05∶1的条件下,测试了其对乙炔氢氯化反应的催化性能。利用ICP-AES、红外光谱、XRD和TG等手段对催化剂进行表征。结果表明,加入2,5-二甲基吡嗪后,Cu表观质量分数为17%的催化剂的乙炔转化率可达74.02%,氯乙烯选择性可达97.19%。2,5-二甲基吡嗪提高铜基催化剂活性的原因在于其可以减少铜物种聚集,提高活性组分的分散度;可以产生Cu-N配位化学键,锚定铜物种使其稳定;可以抑制催化剂积碳,减少积碳引起的失活现象。

某油冷却器换热管泄漏原因

某公司生产的油冷却器换热管在投入使用9~12个月后发生腐蚀泄漏现象。采用宏观观察、化学成分分析、金相检验、扫描电镜和能谱分析、原子吸收光谱分析等方法分析了管道腐蚀泄漏的原因。结果表明:油冷却器换热管介质中的氯离子和硫离子在管内壁积垢中沉积并富集在管壁基体前沿,导致内壁产生大量点腐蚀,点腐蚀位置与未腐蚀位置形成大阴极小阳极腐蚀电池,增大了腐蚀速率,在管内介质的冲刷作用下,点腐蚀坑进一步扩大,最终导致管道泄漏。

碱式氯化铜的制备方法及其在动物生产中的应用

碱式氯化铜是一种铜含量高(铜含量58.12%)、不溶于水和有机溶剂的铜源。与硫酸铜比较,碱式氯化铜不吸潮结块、易混匀,对饲料中的维生素破坏小且油脂氧化程度低。目前,饲料级碱式氯化铜通常以印刷电路板生产过程产生的含铜蚀刻液为原料制得,工业含铜废水废渣、化工原料(主要为氯化铜)合成碱式氯化铜由于成本高,工业生产上比较少见。碱式氯化铜对动物生长性能、繁殖性能、免疫能力和肠道健康具有显著影响。文章综述了碱式氯化铜的制备方法及其在动物生产中的应用,为促进碱式氯化铜在动物生产中的高效利用提供参考。

工艺条件对含氟氯化氢催化氧化制氯气的影响

采用等体积浸渍法制备了耐氟铜基催化剂,在99.9%HCl+0.1%HF混合气氛下制氯气,通过正交实验考察了反应温度、HCl和O_(2)体积比、质量空速对HCl单程转化率的影响。结果表明,在反应温度为390℃、HCl和O_(2)体积比为2∶1、质量空速为1 h^(-1)的最佳反应条件下,氯化氢单程转化率可达92.5%;为进一步验证催化剂稳定性,运行1500 h后HCl单程转化率稳定在91%~93%之间。通过ICP分析,催化剂中活性组分Cu元素流失率为1.175×10^(-5)g/h,初步估算稳定运行10000 h后,Cu流失仅为催化剂Cu元素添加量的1.68%,说明该催化剂具有较好的活性、稳定性和耐氟能力。

氯乙烯合成用改性催化剂的研究

介绍了以盐酸、硝酸、氢氧化钠改性后的活性炭为载体,制备10%氯化亚锡-10%氯化铜-[Bmim]BF 4离子液体催化剂的工艺。讨论了乙炔和氯化氢在不同反应温度和不同反应时间条件下合成氯乙烯的收率。结果表明:用盐酸和硝酸处理活性炭制备的催化剂的稳定性和催化活性均有所提高,用氢氧化钠处理活性炭制备的催化剂的催化活性有所降低。