从蟋蟀中提取壳聚糖的研究

通过从蟋蟀中提取壳聚糖工艺的研究,提出了获得较高质量的壳聚糖的适宜工艺条件:①脱矿物质用1HCl 浸泡12 h.②脱蛋白质及脂类用5～15NaOH,在90℃下处理4～6 h.③脱乙酰基用40NaOH在130℃下处理3 h.     

Small dams need consideration in riverscape conservation assessments

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面向对象的技术研究

C、c＋＋、Java和c#等语言为背景，对面向对象和数据抽象作出了一个非正式的定义，将支持数据抽象等同于定义和使用新数据类型的能力，而将支持面向对象编程等同于对类层次的表达能力。同时，讨论了通用编程语言为支持此种编程格式而必须提供的机制。     

Water resource management – the water utilities view

Abstract The potential effects of abstraction for water supply on salmonid populations in England and Wales are reviewed. The duties of water resource planning and the contribution of the water industry investment in river basin management planning are discussed. Given the possible effects of climate change on public water supply and demand, and the uncertainty of hydroecological relationships, key principles to ensure long‐term investment by water utility companies to meet European Union Water Framework Directive standards achieve the best benefit for salmonids are recommended.     

Water resources management of the southern rivers of Russia with reference to fisheries requirements

Water consumption from Russia's southern rivers has increased substantially in recent years as a consequence of intensified economic activity. The volume of irreversible river-flow withdrawal from the Azov Sea basin varies between 11 and 13 km³ year^1. The majority of the abstracted water is used for irrigation. By 1990, the decrease in discharge into the Caspian Sea was 41 km³ year^1. Withdrawals of water from the Kura, Terek, Ural and other rivers have so far exceeded the ecologically admissible limits and become critical. The paper discusses methodological approaches for the elaboration of standards for water withdrawal and ecologically safe discharges into the southern seas. New data are presented on the dynamics of fish abundance as a function of the hydrological characteristics of rivers and water salinity. The results of the system analysis and regressive modelling formed the basis of a programme to develop policies for water management for fisheries in the lower Don. The principles and criteria for water withdrawal under variable hydrological regimes for the rivers entering the Azov and the Caspian Seas should be tested for their applicability for other water bodies (e.g. rivers, water reservoirs and lakes).     

槐花抗氧化剂的提取及其抗氧化性的测定

将槐花粉碎后用７０％酒精回流抽提，经减压浓缩得暗褐色萃取物，随后用淀粉法、酸水解法、水浴法、乙酸乙酯法处理得有效成分，以其０．０２％的浓度或和Ｖ＿ｃ及柠檬酸协同作用于油脂，ＰＯＶ法测定其抗氧化性能，结果以乙酸乙酯法得到的产物抗氧化性最好，Ｖ＿ｃ和柠檬酸对抗氧化剂有增效作用。     

彩色棉纤维色素提取和测定方法的研究

以白色棉、棕色棉和绿色棉的成熟纤维为材料,用有机溶剂(乙醇、乙醚、二甲苯),酸性、碱性溶液,以及HNO3/乙醇溶液,分别对不同颜色纤维中的色素进行提取. 结果表明,采用HNO3/乙醇溶液消煮法可以将彩色纤维中的色素物质提取出来. HNO3/乙醇的色素提取液在光谱波长为412 nm处有一个最大吸收峰;颜色深浅不同的棕色或绿色棉纤维提取液在这一波长处的吸收值差异显著,随着纤维颜色的加深提取液吸收值增大(0.063 4～0.990 0);白色纤维的提取液在412 nm处的吸收值很小(0.007 2),可忽略不计.因此,用HNO3/乙醇法提取棉纤维色素和用分光光度计比色法可以定量比较彩色棉纤维的色泽深浅. 在用酸性和碱性处理棕色和绿色棉纤维时,发现纤维颜色的深浅程度随处理溶液酸碱度的变化而变化,而且这种变化是可逆的.纤维中色素含量与纤维素含量存在负相关.     

黄土丘陵沟壑区典型小流域SCS-CN方法初损率取值研究

 【目的】初损率是SCS-CN方法进行流域地表径流预报的基础输入参数之一,影响着径流模拟精度。论文通过研究确定黄土丘陵沟壑区典型小流域初损率取值,为SCS-CN方法在该地区的适用性评价提供参考。【方法】SCS-CN方法中,初损率定义为初损量（Ia）与流域最大蓄水能力（S）的比值,通常取标准值0.2。然而,已有研究表明不同区域初损率取值存在差异。论文选取黄土丘陵沟壑区桥子西沟小流域1987—2006年14场典型降雨事件,采用反算法（BC）和事件分析法（EA）确定流域初损率。【结果】结果表明,两种方法计算初损率均小于标准值0.2,事件分析法计算值（0.17）与反算法计算值（0.1）相比略偏大。初损率取0.1、0.17和0.2分别计算研究降雨事件径流深,采用皮尔逊相关系数（r）、模型效率系数（E）、相对误差（RE）、绝对误差（AE） 和图形拟合5种评价标准分析模拟结果,确定研究流域初损率为0.1。论文采用两种算法计算桥子西沟流域初损率,结果与标准值显著不同,初步推断是研究流域与SCS-CN方法最初研发区域地质地貌及气候条件存在较大差异所致。【结论】不同区域应用SCS-CN方法时,需利用当地观测数据率定研究流域初损率,才能进行流域地表水文模拟。     

鱼皮胶原多肽口服液的研制

以草鱼皮为原料,用胃蛋白酶提取胶原多肽,探讨了影响鱼皮胶原多肽水解度的主要影响因素,优化了酶解工艺条件,发现鱼皮胶原多肽最佳酶解条件为料液比6%、酶用量30 mg/g蛋白、酶解温度40℃、pH值2.0;然后以提取的鱼皮胶原多肽为原料配制胶原多肽口服液,得出了胶原多肽口服液的最佳配方为鱼皮胶原多肽液20 mL、蜂蜜5 g、葡萄糖1 g。     

Assessing near‐bed velocity in a recruiting population of the endangered freshwater pearl mussel (Margaritifera margaritifera) in Ireland

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