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排序方式: 共有65条查询结果,搜索用时 15 毫秒
1.
随着“C&C”在全世界掀起了即时战略的热潮,各大公司也看准卖点纷纷推出了自己的产品以占领市场。著名的Activison公司推出的《黑暗王朝》是其中的姣姣者之一,在德国和澳洲两地均为卖座冠军,世界总销售已突破40万拷贝。它打破传统即时战略的老风格,开创了有自己风格的新纪元。 《黑暗王朝》不但保留了传统即时战略中(探险(Exploration)、开发(Exploloition)、扩张(Expansion)以 相似文献
2.
The preparation of copper arsenite with arsenic trioxide was presented and its application in the purification of copper electrolyte was proposed. The variables of n(OH^-)/n(As), n(Cu)/n(As), NaOH concentration, reaction temperature and pH value have some effects on the yield of copper arsenite. The optimum conditions of preparing copper arsenite are that the molar ratio of alkali to arsenic is 2:1, NaOH concentration is 1 mol/L, the molar ratio of copper to arsenic is 2:1, pH value is 6.0 and reaction temperature is 20℃. The yield of copper arsenite is as high as 98.65% under optimum conditions and the molar ratio of Cu to As in the product is about 5:4. The results of the purification experiments show that the removal rate of antimony and bismuth is 53.85% and 53.33% respectively after 20g/L copper arsenite is added. The purification of copper electrolyte with copper arsenite has the advantages of simple technique, good purification performance and low cost. 相似文献
3.
湖泊水质卫星遥感方法及其应用 总被引:17,自引:4,他引:17
通过系统性的常规水质采样分析与水面光谱测量外场同步试验,建立了由FY-1C多通道扫描辐射计、Landsat卫星TM和Seastar卫星SeaWiFS等在轨卫星多通道遥感器以及一组设想的遥感通道遥感反演叶绿素a浓度和总悬浮物浓度的优化通道组合模型,提出了一种利用水面上标准反射板的反射光谱和遥感图像本身确定大气透过率和反射率从而实现大气校正的水质指标卫星遥感反演方法.所建立的模型和方法被用于遥感解译我国典型富营养化湖泊太湖和滇池从80至90年代的富营养化程度及其分布状况随年份的变化.本项研究为进一步开展湖泊水质业务化卫星监测打下了基础. 相似文献
4.
文章介绍了三相电能表检定装置扩展不确定度的分析与计算方法,指出:误差分析的关键是如何确定扩展不确定度。 相似文献
5.
6.
The sedimentary manganese deposits occurring in Gufeng formation of the Permian in Guichi area, south Anhui Province, include manganese carbonate deposit formed by sedimentation, and manganese oxide deposit made by later oxidation. The total REE contents of these samples are relatively low ( < 250 × 10-6), belonging to LREE-enriched type,showing LREE enrichment during the process of formation of Mn deposit, especially during Mn-oxidizing process. Three normalized REE patterns and SCNA-normalized trace elements spider diagrams of the Mn-bearing sequence rocks and ores in this area reflect their same origin of ore sources, which is similar to rock-forming and ore-forming conditions. The Mnforming materials primarily came from the continent with higher mature degree and single material source. The δEu and δCe negative anomaly and Ce anomaly ( < - 0.1 ) manifest that Mn-bearing sequence of the Permian was mostly formed in marine basin and oxidative environment. The Sr and Ba anomaly, Sr/Ba and Co/Ni values reflect the Mn deposit environment was of deep water and high-salinity of marine facies. Although the Ce/La (mean 1.05), Y/Ho (25 ~ 41.5) and trace metals show a variety of correlations with Mn in the ten rock samples, which show multiple sources for the manganese, the analysis of geochemical characteristics indicate that the material sources of Mn deposit have been primarily terrestrially derived. Another source of the manganese probably comes from the seafloor volcanism in this area. Analysis of sedimentary features and geohistoric evolvement reveals that the maximum transgression of the Qixia Period, ore district is then in deep shelf-basin sedimentary setting and the Mn-bearing sequence is deposited. 相似文献
7.
Novel technology of purification of copper electrolyte 总被引:10,自引:1,他引:10
The effects of arsenic with different valence states on the purification of copper electrolyte were studied and a novel technology of purification of copper electrolyte by copper arsenite was proposed. The results show that the purification performance of As(Ⅲ) compounds is better than that of As(Ⅴ) compounds. The purification technology by copper arsenite has the advantages of simple operation, high purification performance and low cost in comparison with other technologies and its appropriate purification conditions are that copper arsenite concentration is 18 g/L, reaction temperature is 65 ℃ and reaction time is 8 h. The removal rates of Sb and Bi are 53.22% and 58.67% respectively under these conditions. The purification principle show that a kind of yellow precipitate mainly composed of arsenic, antimony ( Ⅴ ), bismuth and oxygen forms in electrolyte after copper arsenite is added, and consequently antimony and bismuth are removed from electrolyte. 相似文献
10.
工程竣工造价结算审核是工程造价结算的必要途径,通过工程竣工造价的结算可以科学合理的掌握整个工程的造价,提升建筑公司的核心竞争力,也能节约成本。目前我国工程竣工造价结算审核还处于发展阶段,有很多还待完善的地方..本文中笔者将从理论和实践两个方面,对工程施工阶段的造价预算特点,以及工程竣工造价结算审核的特点的分析,对工程竣工造价结算审核策略提出一些建议和意见,希望对我国的工程竣工造价结算审核的健康发展有所帮助。 相似文献