高效液相色谱法测定蜜饯中乙二胺四乙酸二钠的含量

运用高效液相色谱法测定以蜜饯中乙二胺四乙酸二钠。样品用水溶解,加入氯化铁溶液,采用C18柱分离,以甲醇和0.075 mo L/L KH_2PO_4水溶液进行梯度洗脱,出峰时间定性,外标法定量。结果表明:该方法的乙二胺四乙酸二钠检出限为20 mg/kg,线性范围为2~50μg/m L,相关系数r=0.999 83,回收率为94.2%~97.5%,相关标准偏差(RSD)0.47%。该方法前处理简便、灵敏度高、分离效果好、精确度高和精密度好,对蜜饯中乙二胺四乙酸二钠的含量测定更有针对性。     

红枣枣醋发酵工艺的优化

以新疆"哈密大枣"为原料,结合现代醋酸发酵技术制作冬枣枣醋,对枣醋发酵温度、醋酸菌接种量、初始酒精度和初始pH值4个影响因素进行分析,探讨冬枣枣醋最佳发酵条件,试验结果表明:当发酵温度为30℃,醋酸菌接种量为3%,酒精度为6%,初始pH为3.0时,15 d时醋酸含量达到5.76 g/100 mL。     

黑龙江省泥炭中黄腐酸含量及开发途径

泥炭是黑龙江省重要的自然资源，腐植酸是泥炭主要特征指标，黄腐酸是腐植酸的重要组分，其分子量最小、活性最大、应用十分广泛；在省内５个主要区域，按平面和剖面选取大型泥炭矿做黄腐酸含量调查分析。     

国外间苯二酸供需动态

简述了美国，西欧和日本市场间苯二酸供需和发展。由于国内该产品系列尚属空白，因此建议加强发展间苯二酸及其衍生产品的生产和研究。     

An Iterative Process for International Negotiations on Acid Rain in Northern Europe Using a General Convex Formulation

This paper proposes a game theoretical approach of internationalnegotiations on transboundary pollution. This approach is distinguished bya discrete time formulation and by a suitable formulation of the localinformation assumption on cost and damage functions: at each stage of thenegotiation, the parties assign the best possible cooperative state, giventhe available information, as an objective for the next stage. It is shownthat the resulting sequences of states converges from a non-cooperativesituation to an international optimum in a finite number of stages.Furthermore, a financial transfer structure is also presented that makesthe desired sequence of states individually rational and stategically stable.The concepts are applied in a numerical simulation of the SO₂transboundary pollution problem related to acid rain in Northern Europe.     

International Cooperation Behind the Veil of Uncertainty – The Case of Transboundary Acidification

The complexities of international environmental problems are only poorly understood. Hence, decision makers have to negotiate about abatement measures even though they do not know the 'true' model of the ecological system and have only a rough idea about the costs and benefits of their action. It will be analysed to what extent this kind of 'model uncertainty' – where players do not only have incomplete information about the payoff functions of the other players, but also about their own payoff function – affects the prospects of international cooperation. Using a simple game-theoretic model, it is shown how countries can use the veil of uncertainty to hide their distributional interests. The arguments are based on a deviation from the common prior assumption, which seems particularly questionable in a setting comprising various countries with different cultural and scientific backgrounds. Finally the model will prove useful to quantitatively and qualitatively illustrate the central role of model uncertainty in the negotiations of the first Sulphur Protocol signed to combat transboundary acidification.     

生物柴油的发展现状及它在中国的应用前景和应注意的问题(Ⅱ)

作为得自于动植物油脂的脂肪酸甲酯，即所谓的生物柴油是一种来自于动物或植物的可再生燃料资源。目前在世界各国正掀起一开发利用生物柴油资源的热潮。对目前国际上生物柴油开发和利用现状进行了介绍，同时也对中国生物柴油的开发和应注意的问题进行了阐述。     

钛白废酸回收技术研究

通过臭氧氧化技术将钛白废酸中的Fe2 氧化成Fe3 ,再用萃取法除去Fe3 。考察了络合剂(盐酸)浓度、萃取剂、萃取相比和多级错流萃取级数等对Fe3 萃取率的影响,初步探索了反萃法回收萃取剂及萃取剂的循环利用。结果表明,当盐酸浓度为3.4～4.0mol/L时,几乎可完全络合溶液中的Fe3 ,Fe3 的萃取率随相比(O/W)的增加而增大,萃取级数愈多萃取效果愈好。O/W=1∶1的单级萃取与总相比O/W=0.5∶1的四级错流萃取率接近。当反萃相比(W/O)=1.5∶1时,Fe3 的反萃率达97%,萃取剂经过6次萃取—反萃循环后,Fe3 的萃取率没有明显下降。去除Fe3 后的钛白废酸,经蒸馏浓缩到70%左右,再与浓硫酸混合后可用于钛白粉的生产,蒸馏过程中得到的盐酸循环使用,反萃出来的Fe3 可作为生产铁红的原料。     

由磷肥企业副产氟硅酸制备氟化钠的研究

重点介绍了以磷肥企业副产氟硅酸为原料制备氟化钠的新工艺。首先用氨水氨化脱硅得到氟化铵溶液,再向氟化铵溶液加氯化钠合成氟化钠。对影响反应的温度、时间、物料配比等因素进行了探讨,得出具体工艺为:(1)氨化反应:H2SiF6浓度在12%～14%之间,氨水过量25%,反应温度为60～70℃,反应时间120min。(2)氟化钠合成:氯化钠过量15%～20%,反应温度85～90℃。产物氟化钠纯度大于98%,收率大于80%。     

黄河中游流域土壤活性调查及其激活研究

研究了氢氧化钠、水玻璃、氢氟酸和磷酸对黄河中游不同地区土壤的侵蚀激活效果,结果表明,磷酸对土有很好的激活作用,掺入磷酸的土做成试件抗压强度较不掺加磷酸的土有很大提高,并且随着磷酸掺量的增多,强度继续增长,耐水性也有很大改善。红外及微观分析表明,磷酸能够改变土粒表面的羟基团,并且磷酸与土中的碳酸盐等生成肉丝状的磷酸钙晶体,分布在土粒的周围,胶结土壤。