Tongling''''s copper capacity boost

The expansion project at Tongling NonferrousMetals Group Co.will help boost its copperproduction capacity to 310,000 tons,accordingto an industry report.The whole projects con-sist of the technical renovations and expansionsat five of the company's smelters or mine in-cluding Jinchang Smelter,Jinlong Copper Co.,Zhangjiagang Copper Co.,the First Smelterand Dongguashan Mine.     

Statistics on China''''s copper industry

According Io a recent report from the In-formation Center under the State Nonfer-rous Metals Industry Administration(SNMI-A),by the end of 1999,China had 312copper enterprises including both theState-owned and non State-owned enter-prises(from smelting backwards)with an-nual sales volume exceeding RMB 500yuan(US＄604,600).This number accountedfor 10.71 per cent of the total nonferrousmetals producers in China.There were 257,000 people working forthe industry,accounting for 19.35 per cent     

Largest copper deposit found in Xinjiang

China has found a large copper depositin the east Tianshan area in Xinjiang Au-tonomous Region,according to the Min-istry of Land Resources(MLR).Jiang Chengsong,MLR vice-minister said ata press conference that the typical ore body     

New copper fabricating line starts operation

Guangzhou Copper Fabricating Plant has com-pleted the removal and technical renovationswith operation started recently,according to anindustry report.The new plant, under the ad-ministration of Guangzhou Nonferrous MetalsGroup,has changed its name to GuangzhouCopper Fabricating Co.Ltd.     

China's foreign trade of copper in 1998

Compared with the previous year,China'sforeign trade of copper in 1998 didn'tchange much in general.Although tradevolume of refined copper went up signifi-cantly,the import structure remained basi-cally the same.With some export slip andsome increase on import,China's foreigntrade of copper still showed an un-favourable balance.     

The impact of tax exemption on copper

The expected tax exemption on copper importsin the next three years (see our last issue underthe policy column) will have some significantinfluence on the domestic copper market, ac-cording to an analysis report.     

Jiangsu Jurong Xiangrenqiao copper mine begins construction

Xianrenqiao Copper Mining Co. Ltd. in Jurong was established in August, 2004 and was granted the mining license in Jiangsu Province in August, 2006. The company is under the     

Jinchuan plans to expand its copper production capacity

Jinchuan Nonferrous MefaIs CO.is plan-ning to expand its copper production ca- pacity from 26,000 tons/y to 50,000 tons/y,according to an industry report.At present,the company's copper re-sources mainly come from its own nickelmines and its copper production scale is     

Chinese copper consumption will have a massive growth

For the past year, the actual copper consumption in China has aroused extensive argument in the business circle. The de-stoking of manufacturers and the massive sale from state reserve bureau(SRB) caused more difficulty in     

Cyclic response of polycrystalline copper—composite-grain model

The cyclic deformation of polycrystalline f.c.c. metal is treated by viewing differently-oriented grains as the components of a composite material. Following a brief review of cyclic deformation in single- and polycrystals, a qualitative model of deformation behavior is developed by considering multi-slip regions to be relatively “hard”. These regions are of two kinds: (a) volumes adjacent to grain and twin boundaries where multi-slip develops from compatability requirements, and (b) whole grains which happen to be favorably oriented for multi-slip because of texture effects. The interiors of grains favorably oriented for single slip are considered as “soft”. These considerations are validated by the experimental fact that the substructure evolution observed in 〈111〉-〈100〉 textured copper seems to be better described if grain-orientations are viewed in terms of the individual stress-state for each grain, and therefore the cyclic response of differently-oriented grains can be taken as that of the corresponding differently oriented single crystals. Finally, the model is shown to account qualitatively for some of the results reported previously from our laboratory: e.g. the differences in the cyclic response and levels of strain localization of fine-grained/weak-textured and coarse-grained/strong-textured copper, and the absence of a plateau in the cyclic stress-strain curve of fine-grained/weak-textured copper.     

Sintered copper–graphite powder compacts forindustrial applications

Abstract

Studies were made on copper/graphite based powders and sintered compacts for industrial applications. The dependence of particle shape on friction in the powder mass, compression ratio, and electrical receptivity of powder metallurgy components was studied using near spherical precipitated copper powders and angular or flakelike powders generated by mechanical comminution. Results reveal that powders with particles that are nearly spherical in shape have lower friction, lower compression ratios, and higher electrical resistivities in sintered compacts than powders with acicular or flakelike particles. Also, the effects produced by the small additions of lead and zinc (up to 2·5 wt-%) on the electrical resistivity and hardness of sintered copper–graphite compacts are also presented, and the influence of variation of briguetting pressure is discussed.     

Refined copper production rose in the first half

China's refined copper production has beenincreasing rapidly since the beginning ofthis year.By the end of June,total outputreached 607,600 tons,up by 25 per centyear-on-year according to figures releasedby the State Statistics Bureau.     

Quota on import of copper resources with tax exemption

To improve the competitiveness of China'scopper producers upon China's expectedentry into the WTO,the State Council hasdecided to further reduce the cost of im-ported copper concentrate,copper scrapand blister copper by giving tax exemptionto the domestic producers.     

China's monthly foreign trade volume of copper in 1998

己处O之O、OUSfo3SO、牙伪勺刀CChina's monthly foreign trade volume of copper in 1998~~     

Deformation processes in hot worked copper and α brass

The generation of the fine grained, dynamically recrystallized microstructure has been studied in hot rolled copper and α brasses and in 70:30 brass deformed by hot torsion. The new grains, which developed preferentially at grain boundaries and inhomogeneities of deformation, contained none of the deformation features present in unrecrystallized parts of the microstructure. This observation is contrary to theories of dynamic recrystallization which imply that the microstructure contains a spectrum of grains ranging from just recrystallized to severely deformed. Texture studies showed cold rolled textures at low rolling temperatures but in the case of copper the texture became quite flat after rolling at 350 and 425 °C. Flat textures were associated with a minimum grain size. At higher rolling temperatures the textures were again typical of cold rolled material. It is suggested that while normal slip processes are operating at all temperatures there is an additional contribution from grain boundary deformation processes associated with fine grained microstructures. Such processes would account for the absence of normal deformation features from dynamically recrystallized microstructures.     

China's foreign trade volume of copper 1997-1998

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Domestic copper consumption still looks healthy despite world economic slowdown

Although the world economy is generally in astate of depression particularly since the ter-rorist attacks in the US,China's domestic con-sumption of copper has kept increasing over thepast months.Statistics from the State shows that in the firstthree quarters of this year,China's GDP grewby 7.6 per cent year-on-year,which is muchhigher in comparison to the world majoreconomies in other areas.     

Synthesis and characterization of lanthanum-doped curcumin-functionalized antimicrobial copper oxide nanoparticles

Flavonoid-based nanomaterials have extensive potential in antimicrobial research because of their non-toxicity,large-scale producibility,and chemical stability.An efficient combination of flavonoids and rare earth metals can have excellent antimicrobial properties owing to their robust medicinal and physicochemical properties.In this study,we synthesized copper oxide(CuO) nanoparticles(NPs)using a reflux reaction and repeated doping with the rare earth element lanthanum to prepare La-CuO NPs.Nex...