黄山市居民头发中锌、铜、钙、镁、钼、硒水平分析

对黄山175例居民头发中锌、铜、钙、镁、钼、和硒进行了测定，锌、铜、钙、镁、钼、硒的含量分别为141．51μg／g，8．05μg／g，720．10μg／g，59．76μg／g，59．04μg／g和0．196μg／g。     

贯穿于东北抗联第一路军发展史中的三条主线(上)

统一战线工作，根据地建设和武装斗争，是制约东北抗联一路军发展的三个主要因素，是贯穿于东北抗联一路军发展史中的三条主线。这三个主要因素，三条主线互为条件，互相促进。其中，根据地建设为抗联一路军的武装斗争提供了重要依托，统一战线工作为抗联一路军的武装斗争壮大了力量，抗联一路军的武装斗争则直截沉重地打击了日本侵略。抗联一路军在其历史上长期取得的辉煌和后期遭受的挫折，都可以从这三个方面得到说明。     

悬浮液进样-火焰原子吸收光谱法测定怀地黄中的铜

介绍了一种悬浮液进样火焰原子吸收光谱法（FAAS）测定怀地黄中铜的方法。以琼脂为悬浮剂将粉碎、过筛的怀地黄样品均匀、稳定地悬浮于琼脂溶胶中,直接喷入空气-乙炔火焰中,采用标准加入法测定,省去了以往繁琐的样品化学前处理过程,解决了因操作环节多,被测元素丢失或污染所引起的分析误差。用该法测定怀地黄样品,并与湿法消化法对照,获得满意结果。该方法简便、快速,准确,可以代替湿法消化法。     

Socio-cognitive dynamics of knowledge building in the work of 9- and 10-year-olds

This study examines four months of online discourse of 22 Grade 4 students engaged in efforts to advance their understanding of optics. Their work is part of a school-wide knowledge building initiative, the essence of which is giving students collective responsibility for idea improvement. This goal is supported by software—Knowledge Forum—designed to provide a public and collaborative space for continual improvement of ideas. A new analytic tool—inquiry threads—was developed to analyze the discourse used by these students as they worked in this environment. Data analyses focus on four knowledge building principles: idea improvement; real ideas, authentic problems (involving concrete/empirical and abstract/conceptual artifacts); community knowledge (knowledge constructed for the benefit of the community as a whole); and constructive use of authoritative sources. Results indicate that these young students generated theories and explanation-seeking questions, designed experiments to produce real-world empirical data to support their theories, located and introduced expert resources, revised ideas, and responded to problems and ideas that emerged as community knowledge evolved. Advances were reflected in progress in refining ideas and evidence of growth of knowledge for the community as a whole. Design strategies and challenges for collective idea improvement are discussed.

重金属铜、锌、铅对苦荞种子萌发的影响

铜（Cu）、锌（Zn）、铅（Pb）都是土壤重金属污染源,对土壤、植物、动物及人体产生巨大危害。本文以苦荞种子为实验材料,研究经不同浓度硫酸铜、硫酸锌和乙酸铅催芽后的苦荞种子发芽率、发芽势、发芽指数和活力指数的变化情况。结果表明：当硫酸铜、乙酸铅浓度大于100 mg/L时,苦荞种子发芽率、发芽势和发芽指数均会受到不同程度的抑制,不同浓度硫酸锌对苦荞种子的发芽率、发芽势及发芽指数均无影响。经3种不同浓度重金属盐催芽后的苦荞种子,幼苗胚根平均长度和种子的活力指数均随着重金属盐浓度的增加而降低,且三种重金属盐对其抑制效果的大小顺序为硫酸铜〉乙酸铅〉硫酸锌。     

铜锌铁清料法加工皮蛋的比较研究

在用NaOH清料法直接加工皮蛋过程中,采用了CuSO4·5H2O 、ZnSO4·7H2O和FeSO4·7H2O三种微量辅料,并对单独或混合使用这些微量辅料加工溏心皮蛋的优劣进行了比较. 研究表明,当用NaOH代替Na2CO3和CaO直接加工皮蛋时,“铜法”、“铜锌混合法”和“铁锌混合法”效果最优,“锌法”对加工时间要求严格且效果略次,“铁法”不能成功.     

Spatial distribution of Cd and Cu in soils in Shenyang Zhangshi Irrigation Area （SZIA）, China

Heavy metal contamination of soils, derived from sewage irrigation, mining and inappropriate utilization of various agrochemicals and pesticides, and so on, has been of wide concern in the last several decades. The Shenyang Zhangshi Irrigation Area (SZIA) in China is a representative area of heavy metal contamination of soils resulting from sewage irrigation for about 30 years. This study investigated the spatial distribution and temporal variation of soil cadmium (Cd) and copper (Cu) contamination in the SZIA. The soil samples were collected from the SZIA in 1990 and 2004; Cd and Cu in soils was analyzed and then the spatial distribution and temporal variation of Cd and Cu in soils were modeled using Kriging methods. The results show that long-term sewage irrigation had caused serious Cd and Cu contamination in soils. The mean and the maximum of soil Cd are markedly higher than the levels in second grade standard soil (LSGSS) in China, and the maximum of soil Cu is close to the LSGSS in China in 2004 and is more than the LSGSS in China in 1990. The contamination magnitude of soil Cd and the soil extent of Cd con- tamination had evidently increased since sewage irrigation ceased in 1992. The contamination magnitude of soil Cu and the soil extent of Cu contamination had evidently increased in topsoil, but obviously decresed in subsoil. The soil contamination of Cd and Cu was mainly related to Cd and Cu reactivation of contaminated sediments in Shenyang Xi River and the import of Cd and Cu during irrigation. The eluviation of Cd and Cu in contaminated topsoil with rainfall and irrigation water was another factor of temporal-spatial variability of Cd and Cu contamination in soils.     

关于CuS在浓盐酸中溶解性的分析与讨论

以硫化钠为原料制备硫化铜,试验其在不同浓盐酸中的溶解性,并对实验现象和所得结论做出合理的解释。     

火焰原子吸收法测定佛手瓜中钙镁铜锌

研究了用火焰原子吸收法测定佛手瓜中钙、镁、铜、锌等元素的方法。佛手瓜样品经湿法消化处理后,在最佳仪器条件下,对上述元素进行测定,钙、镁、铜和锌的回收率分别为98．9％、98．0％、97．1％及103．2％,相对标准偏差为0．34－1．40％。     

反催化动力学光度法测定痕量铜

研究了铜阻抑过硫酸钾氧化甲基红褪色反应;应用动力学光度法原理测定铜条件.试验表明,在酸性介质中,其体系灵敏度提高,建立了反催化动力学光度法测定铜最佳测定条件,即过硫酸钾溶液(0.01mol/ml)7ml;无水乙醇6ml:磷酸溶液(1mol/L)0.5ml:甲基红溶液(0.5mmol/L)5ml,其检出限量为8.349×10~(12)g/mL:线性范围0.01—0.08μg/25ml.方法选择性高,一定量的常见离子不干扰测定.可用于测定发样、水样和豆样中的铜.