全自动总氮在线分析仪的研制

将在线加热消解、在线冷却、镉柱还原与偶氮比色法相结合,并采用流动注射分析技术实现了全自动总氯分析仪的研制工作。该系统可在无人干预的情况下,自动地执行从环境采样、预处理、测定、数据分析和最终传输的全过程。实验证明,此系统消耗试剂量少,测定范围宽（0～100mg／L）,检出限低（0．042mg／L）,测定快速（3样／时）,精密度高（RSD〈0．45％）,实际水样的加标回收率均在93．3％～105．O％之内,可用于在线快速测定总氮。     

铅暴露对发育期大鼠肾脏超微结构影响

目的:从光镜和电镜水平观察铅暴露对发育期雄性大鼠肾组织的形态学影响.方法:3周龄SD雄性大鼠,随机分为对照组和染铅组.染铅组腹腔注射0.2%乙酸铅溶液(0.2 mL/100 g体质量),隔日1次,共20次,对照组同时注射生理盐水.实验结束后,测量各组动物血铅和血中游离原卟啉,取肾组织作光镜和透射电镜观察.结果:与对照组...     

Fractions and Bioavailability of Soil Inorganic Phosphorus in the Loess Plateau of China under Different Vegetations

Plants play an important role in soil phosphorus nutrition. However, the effect of plants on phosphorus nutrition in soils of the Loess Plateau of China is not well understood. This study was conducted to reveal the relationships between plants and phosphorus' fractions and availability in the Loess Plateau of China. Twenty-two plant communities were surveyed and soil samples under different plant canopies were collected for the determination of soil properties and inorganic phosphorus fractionation. The results showed that Leguminosae and Lilaceae reduced pH and increased organic matter, cation exchange capacity, total and Olsen phosphorus in soils under their canopies, while Labiatae and Rosaceae increased pH and decreased organic matter, cation exchange capacity, total and Olsen phosphorus in soils under their canopies. The contents of Ca2P, CasP, AI-P and Fe-P were highly related with soil Olsen phosphorus. They were all higher in soils under Leguminosae and Lilaceae and lower in soils under Labiatae and Rosaceae. The results of this study indicate that Leguminosae and Lilaceae improved phosphorus nutrition in soils, yet Labiatae and Rosaceae impeded the improvement of phosphorus nutrition in soils under their canopies, which will be of more help to instruct vegetation restoration in the region and provide information for soil development.     

热处理温度对海水循环泵叶轮用双相不锈钢冲击性能的影响

针对海水循环泵叶轮的服役条件,利用烟台台海玛努尔核电设备有限公司提供的材料,研究了热处理工艺对GX2GrNiMoN22-5-3双相不锈钢冲击性能的影响。结果表明,双相不锈钢的冲击性能在常温下随固溶温度的升高而逐渐下降,并且在1120～1160℃固溶温度范围内下降明显,在1160～1200℃温度范围内下降趋势缓慢。铁素体含量测试表明,随固溶温度的升高,铁素体的变化趋势与冲击功的变化趋势具有良好一致性,表明固溶温度升高铁素体含量降低,是冲击功减小的重要原因。对冲击断口形貌进行观察,冲击断口以韧窝型断裂为主。     

A modified Johnson–Cook constitutive model for Mg–Gd–Y alloy extended to a wide range of temperatures

In this paper, a new phenomenological and empirically based constitutive model was proposed to change the temperature term in the original Johnson–Cook constitutive model. The new model can be used to describe or predict the stress–strain relation of the metals deformed over a wide range of temperatures even though the current temperatures were lower than the reference temperature. Based on the impact compression data obtained by split Hopkins pressure bar technique, the material constants in the new model can be experimentally determined using isothermal and adiabatic stress–strain curves at different strain rates and temperatures. Good agreement is obtained between the predicted and the experimental stress–strain curves for a hot-extruded Mg–10Gd–2Y–0.5Zr alloy at both quasi-static and dynamic loadings under a wide range of temperatures ever though the current temperatures were lower than the reference temperature.     

某工厂利用热泵技术回收工业余热的技术改造

本文以某工厂生活热水及采暖系统为研究对象,提出了利用热泵技术回收工艺冷却水余热,并从节能、经济及环保方面分析了技术改造方案的可行性。     

基于BIM的建设工程柔性管理模式分析

BIM技术将在未来引发建筑业新的革命,相较于当前仅仅重视BIM技术方面的优势,将BIM技术与柔性管理相结合,以工程项目管理模式变化为视角分析BIM对建筑业带来的深刻影响,从计划职能柔性化、组织职能柔性化、领导职能柔性化和控制职能柔性化4个角度分析BIM带来的项目管理模式创新。     

地理标志及其对葡萄酒产业作用

地理标志在我国经济建设中发挥着越来越重要的作用。梳理了国内外地理标志的发展及现状,并阐述了我国葡萄酒地理标志保护的现状。分析指出,实施地理标志保护,必将对中国葡萄酒品牌集群形成、市场秩序建立、产品差异化战略、农业产业化发展以及葡萄酒国际竞争力等方面产生重要的促进作用。     

超声辐射下双(苯并三氮唑)烷烃的合成和量子化学研究

以苯并三氮唑和二溴烷烃为原料,在超声辐射下,合成了1,3-双(苯并三氮唑)丙烷和1,4-双(苯并三氮唑)丁烷.通过温度对1,4-双(苯并三氮唑)丁烷产率的影响,确定了最佳反应温度为60℃.另外,运用Gaussian03程序对化合物进行了量子化学计算,发现化合物可以作为柔性双齿配体.     

狭鳕鱼皮胶原多肽组合物水洗面膜的研制

以狭鳕鱼皮胶原多肽、海藻糖和葡萄籽提取物(或藻蓝蛋白)组合物为主要活性成分,以质量分数分别为2.0%,1.0%和4.6%的羧甲基纤维素、海藻酸钠和聚乙二醇1 500为基质主成分,经溶解、搅拌、混合、均质等工艺制备水洗面膜。微生物挑战实验确定以质量分数为1.0%的市售GL-PLUS为面膜防腐剂。体外保湿抗衰老功效研究确定面膜活性成分的添加量(以质量分数计)为胶原多肽3.7%,海藻糖6.5%,葡萄籽提取物(或藻蓝蛋白)0.12%。耐热、耐寒和离心测试结果表明所得面膜具有良好的稳定性。