共查询到20条相似文献,搜索用时 31 毫秒
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用化学镀铜工艺替代有氰电镀是环保、清洁生产的要求。铜包钢丝化学预镀铜生产线主要由放线、退火、水洗、盐酸洗、拉拔定径、电解酸洗、化学镀铜、硫酸盐加厚电镀、中和、钝化、烘干和收线组成。各个生产工序的工艺参数对镀铜质量影响很大,电解酸洗时采用ρ(H2SO4)为200~250g/L,ρ(FeSO4)小于150g/L,电流密度为10~15 A/dm2的工艺参数效果最佳;化学镀铜时采用ρ(CuSC)4·5H2O)为60~80g/L,ρ(H2SO4)为40~50 g/L的工艺参数,并及时添加适量的络合剂,控制镀铜温度在35℃以下,就可得到质量合格的镀铜层。采取该工艺生产的(?)1.53 mm镀铜钢丝可以拉拔至(?)0.6 mm而镀铜层不脱落,满足生产要求。 相似文献
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利用铁、铜间相互作用减轻烤烟铜毒害的研究 总被引:3,自引:0,他引:3
采用温室溶液培养方法,研究利用铁、铜间相互作用减轻烤烟铜毒害。试验结果显示,K326品种Cu2 毒害临界值在1.0-1.2mg/L之间。在低浓度Cu2 (0.1-1.2mg/L)时,烟株吸铁总量增加;高浓度Cu2 (≥1.4mg/L)时,吸铁总量降低。溶液中添加过量的Fe3 (5.61mg/L和11.23mg/L)后,烟株的吸铁量显著增加,而吸铜量明显减少,铁和铜元素由根系向地上部的转运增加,生物量增加4-7倍,可以明显减轻Cu2 的毒害。因此,利用铁、铜间相互作用减轻烤烟铜毒害是可行的。 相似文献
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A.C. Clark E.N. Wilkes G.R. Scollary 《Australian Journal of Grape and Wine Research》2015,21(3):339-350
Copper is one element in wine that has considerable notoriety. While current winemaking practice tends to minimise the amount of copper that results from vineyard and winery sources, the addition of copper(II), either as its sulfate or citrate, to remove sulfidic off‐odours may result in an elevated concentration in the finished (bottled) wine. Residual copper in white wine has been linked to oxidative and reductive spoilage processes, although the mechanisms are at times speculative. The presence of copper has been implicated in haze formation (copper casse) and linked to protein instability. More recent concerns include the coexistence of residual copper and hydrogen sulfide in wine stored under low oxygen conditions. The chemistry of copper is important in both white and red wine. While there are some overlapping issues, especially with respect to sulfidic off‐odours, both white and red wine display their own unique chemistry. Thus, this review describes the state of knowledge of copper in white wine, differentiating between evidence‐based claims and speculation. It also identifies areas of research that will provide a much clearer understanding of the role of copper in wine spoilage. 相似文献
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Yost GP Arthington JD McDowell LR Martin FG Wilkinson NS Swenson CK 《Journal of dairy science》2002,85(12):3297-3303
The objective of this study was to evaluate the rate and extent of Cu repletion in Holstein heifers using two Cu sources (organic and inorganic) at two levels (15 and 30 mg/kg). An additional repletion treatment included a Cu oxide bolus. Heifers (n = 50) were individually fed a total mixed ration fortified with S and Mo at 0.40%, and 15 mg/kg of dry matter of the total diet, respectively. After 111 d of depletion, heifers were stratified by liver Cu concentration and randomly allotted to one of five repletion treatments. Four treatments consisted of feed sources of Cu (feed-Cu), 1) CuSO4 at 15 mg/kg; 2) CuSO4 at 30 mg/kg; 3) Availa-Cu at 15 mg/kg; and 4) Availa-Cu at 30 mg/kg. Availa-Cu is an organic Cu source that produces a Cu-amino acid complex. A fifth treatment, consisting of an intraruminal bolus (IB), provided a single dose of 25 g of CuO needles. Repletion treatments were delivered in the same total mixed ration without supplemental S and Mo. Copper status was assessed in blood and liver samples collected on 14-d intervals for 70 d. Irrespective of treatment, all heifers increased in body weight during the repletion period. Liver Cu increased in each feed-Cu treatment over time. Heifers treated with an IB reached a peak in liver Cu concentration (165.5 mg/kg) on d 28. Mean liver Cu concentrations were higher in heifers receiving 30 mg/kg of Cu compared with heifers receiving 15 mg/kg of Cu. Red blood cell superoxide dismutase (SOD) activity was higher (P < 0.001) in heifers receiving CuSO4 than Availa-Cu (0.98 vs 0.87 U). Also, SOD activity was higher when heifers were supplemented with 30 vs 15 mg/kg Cu (0.98 vs 0.87 U). Heifers receiving the Cu IB had higher SOD activity than heifers receiving feed-Cu sources (1.03 vs 0.92 U). Plasma ceruloplasmin concentration was higher (P < 0.001) in IB-treated heifers vs. other treatments. No differences in plasma ceruloplasmin were detected for feed-Cu source or level. These results indicate that all Cu sources evaluated in this study elevated Cu status of depleted heifers, particularly when provided at higher dietary levels. 相似文献
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目的 确定碳酸铜产品标准拟设置的技术指标,并建立各指标的实验方法。方法 根据现有的碳酸铜国内外标准和资料, HG/T 4825-2015《工业碱式碳酸铜》、默克公司内控指标、欧盟食品安全局关于动物用食品添加剂铜化合物的安全和有效性科学评价, 确定技术指标和试验方法, 并对15批次碳酸铜产品进行实样验证。结果 碳酸铜产品标准拟设置的技术指标有色泽、状态、铜(Cu)含量、氯化物(以Cl-计)含量、硫酸盐(以SO42?计)含量、盐酸不溶物含量、铅(Pb)含量、砷(As)含量、镉(Cd)含量。15批次产品均符合要求。结论 拟设置的技术指标和建立的试验方法具有可行性。 相似文献
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研究了一种支持快速响应的服装供应链补货策略。通过补货率的设计,分析销售商和生产商利润模型,建立支持及时响应的生产商优化批发价策略和补货量策略。通过算例分析说明,如果生产商的补货率不变,只改变补货的批发价,生产商的利润将增加,但销售商的利润将下降,供应链系统的利润也将下降,供应链没有实现协调。反之,如果生产商根据客户需求采取不同的补货率,即使补货的批发价不变,也可实现供应链系统的协调,并使生产商和销售商的利润都获得最大化。 相似文献
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化学镀铜生产焊丝溶液中各成分的消耗与控制 总被引:1,自引:1,他引:0
在化学镀铜焊丝生产中实测镀铜层厚度为0.3μm,由此计算出铜的质量分数为0.116%;通过化学镀铜生产中的反应方程式,计算出每生产1t焊丝要消耗4.54kg的CuSO4.5H2O,消耗1.77kg的H2SO4,产生10.09kg的FeSO4.7H2O,当镀液中ρ(Fe2+)≥44.8g/L时就应调整或更换镀液;指出在化学镀铜溶液配方中CuSO4.5H2O的质量浓度为120~140g/L,H2SO4的质量浓度为80~98g/L,并据此设定酸铜比为1.09~1.11。 相似文献
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meso-四(4-吡啶)卟啉分光光度法测定蔬菜中微量铜 总被引:1,自引:0,他引:1
研究铜与meso-四(4-吡啶)卟啉(TPyrP)的显色反应条件,提出了一个高灵敏度测定铜的分光光度法.络合物的最大吸收波长为422 nm,组成摩尔比为1:1,铜含量在0~1.6 mg/10 mL范围内有较好的线性关系,表观摩尔吸光系数为1.46×105 L/mol·cm,并将其应用于蔬菜中微量铜的测定,结果令人满意. 相似文献
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液相化学发光法测定粮食中的微量铜 总被引:3,自引:0,他引:3
以碘-鲁米诺化学发光反应作指示反应,利用Cu(Ⅱ)对Cr(Ⅵ)-KI反应的抑制作用,建立了化学发光法测定微量铜的新方法。方法灵敏度高,线性范围宽,仪器设备简单,操作方便。用于粮食中微量铜的测定,结果满意。 相似文献
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针对GB/T1548-1989中配制铜乙二胺溶液方法存在的操作复杂、乙二胺与铜的浓度比例以及铜的浓度难以达到规定范围等问题,对铜乙二胺溶液的配制方法进行了改进。从原料试剂的选用、制备方法优化调整等方面对GB/T1548-1989所述的配制方法进行了简化。验证结果表明,采用改进方法配制铜乙二胺溶液,操作简单且准确度高。 相似文献
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Metallized textile has metallic color with reflective effect and smooth handle. The electroless copper plating on fabric using hypophosphite as a reducing agent is feasible process for design application. This study aims to investigate the appearance of the copper-plated Green-PN fabric produced by electroless plating with different deposition conditions including different nickel sulfate concentrations and pH of plating bath. Various colors were produced after the copper-plated fabrics had been exposed to the copper plating bath at 85°C and pH 8.5 for different time. Design application of the electroless copper plating on Green-PN fabric and Black-CVPN fabric was carried out. The electroless copper plating could change the original appearance of the fabric through the deposition of copper particles on the fabric surface. The final pattern was well-defined using many details such as lines and forms created by the design methods. The study laid the foundation of the electroless copper plating for textile design. 相似文献
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目的确定腌制蕨菜复绿的最佳工艺条件,并比较复绿前后铜元素含量。方法以醋酸铜复绿剂不同浓度、不同烫漂时间、不同烫漂温度为因素的进行单因素及正交试验,采用色差仪测定复绿前后腌制蕨菜的色泽变化,利用火焰原子吸收分光光度计测定复绿前后腌制蕨菜的铜元素含量。结果醋酸铜复绿剂最佳复绿工艺条件为:烫漂温度95℃,烫漂时间8 min,复绿剂浓度200 mg/L,复绿前腌制蕨菜中铜元素含量为2.08mg/kg,复绿后铜元素含量为4.61 mg/kg。结论醋酸铜复绿剂对腌制蕨菜有复绿效果,最佳复绿工艺条件下蕨菜中铜含量虽符合林业行业限量标准,但含铜复绿剂也不宜使用过多。 相似文献
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A gelatin copper complex was synthesized with gelatin and copper (II) sulphate. The previous study had indicated that the gelatin copper complex could improve peroxide bleaching effectiveness of cotton in low-temperature. By measuring the spectra absorption abilities of gelatin, copper (II) sulphate and gelatin copper complex respectively, it proved that gelatin copper complex was formed. The catalytic bleaching effectiveness of H2O2/gelatin copper complex system and H2O2/copper (II) sulphate system were compared. The results show that the gelatin copper complex and copper (II) sulphate can catalyze hydrogen peroxide decomposition and improve the whiteness of bleached cotton. Whiteness and capillary effects of the cotton fabric bleached in H2O2/gelatin copper complex system and in H2O2/copper (II) sulphate system at 70℃ are close to the conventional high-temperature bleaching. Besides, the strength retention of the fabric bleached in H2O2/gelatin copper complex system at 70℃ is the biggest among the three samples. The strength retention of the fabric bleached in H2O2/copper (II) sulphate system at 70℃ is the smallest among the three samples. So gelatin copper complex is a more effective catalyst than copper (II) sulphate in low temperature peroxide bleaching of cotton fabric. 相似文献
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为了保证畜产品的安全性,通过动物实验研究了高铜的危害性,根据对某市铜超标情况的调查,运用风险评估软件@RISK4.5建立畜产品中铜的风险评估模型,最终给出日允许摄入量ADI值,以对畜产品中铜超标的风险进行全面评估。为促进畜产品安全,保护消费者健康及有关部门进行食品安全的风险管理提供依据。 相似文献
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文章研究了石榴皮色素的提取工艺、提取液对铜氨纤维的直接染色工艺及铜盐媒染工艺,探讨了温度、pH、时间等因素的影响。结果表明,石榴皮在100℃、pH为13、水煮90 min的条件下,提取的色素最多。用提取液对铜氨纤维在80℃、pH为12时,直接染色70 min,得色量最深。以硫酸铜为媒染剂,采用后媒染法,在80℃、pH为5~7时,媒染45 min,可以获得满意的效果。 相似文献
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Jaimie M. Strickland Thomas H. Herdt Dodd G. Sledge John P. Buchweitz 《Journal of dairy science》2019,102(5):4209-4214
Previous research from our laboratory and others indicates that liver copper concentrations in dairy cattle are commonly well above those recognized as adequate for the nutritional needs of the animal. It has also been speculated that hepatic copper concentrations have been increasing in recent years. Unlike other species, the threshold at which elevated liver copper concentrations becomes deleterious to hepatocytes is not known for cattle. Therefore, the objectives of this study were 3-fold: (1) to delineate differences in the range and mean dry matter hepatic copper concentration for dairy cattle in a retrospective analysis (January 1, 2007, to December 31, 2015), (2) to investigate hepatic copper concentrations in Midwest cull dairy cattle, and (3) to evaluate histologic changes in hepatocellular morphology in the context of copper concentration in cull cows. Furthermore, microscopic changes in hepatocellular morphology or architecture were examined and scored for evidence of inflammation, fibrosis, necrosis, and abundance of rhodanine-stained granules using hematoxylin and eosin and rhodanine staining. The retrospective analysis found copper concentrations within a range of 3 to 1,963 µg/g, with a mean of 473 µg/g. Hepatic copper concentrations in our retrospective study did not increase with time. In our abattoir analysis, copper concentrations ranged from 15 to 978 μg/g, with a mean of 390 μg/g. This study found that the range and mean hepatic copper concentrations were comparatively less in the current abattoir study than copper concentrations in our retrospective analysis. There was no evidence for hepatocellular changes associated with increased copper burdens in this study population. 相似文献