纳米TiO_2改性苯丙乳液内墙涂料的研究

采用物理掺和法,在苯丙乳液中加入锐钛型纳米TiO2,制成内墙涂料,进行抑菌试验和甲醛降解实验研究,分析了纳米TiO2的光催化原理和抗菌机理。结果表明,随着TiO2含量增加,甲醛降解能力和抗菌性能增强,当TiO2含量为4%时效果最好。     

Hot-pressurized fluid extraction of flavonoids and phenolic acids from Brazilian propolis and their cytotoxic assay in vitro

This work has examined the hot-pressurized fluid extraction of seven flavonoids, caffeic acid phenethyl ester and four phenolic acids from Brazilian propolis lumps generating, during the process, fat- and water-soluble extracts. The solid content of water-soluble extract obtained by hot-pressurized water in the presence of 29% natural surfactant was 35.2 mg/mL and was 44% greater than that obtained without natural surfactant. Furthermore the amount of the seven flavonoids and caffeic acid phenethyl ester in the fat-soluble extract exceeded those in the water-soluble sample while, on the other hand, the amount of the four phenolic acids in the water-soluble extract was more than those in the fat-soluble extract. Our findings show that the total solid content and the amount of these 12 active compounds produced by the emulsified hot-pressurized water are 36% and 7% higher, respectively, than those produced by emulsified water at atmospheric pressure. The EC₅₀ value of the free radical scavenging activity of 1,1-diphenyl-2-picrylhydrazyl of the emulsified hot-pressurized water extract was the lowest, and presented the strongest anti-oxidation ability among all the extracts. In vitro cytotoxicity indicated that the water-soluble extract strongly suppressed the growth of leukemia (HL-60, U937), lung cancer (A549, CH27) and liver cancer (Hep G2, Hep 3B) cells in a concentration-dependent behavior.     

磷矿的反应活性及其评价方法研究

介绍评价磷矿反应活性的实验装置;用磷矿在一定浓度酸液中,在一定温度、一定反应时间下的分解率表示磷矿的反应活性。实验研究了不同因素对磷矿反应活性的影响,并测试了11种磷矿的反应活性指数及抗硫酸的阻缓性能。评价方法与实验结果均具有参考价值。     

多层复合丝网过滤效率的研究

用于液—固分离的滤材,其过滤速率是影响过滤设备生产效率的一项重要指标,在实际生产中,要提高设备的过滤效率就要研究如何降低滤材对滤液的阻力。对不同过滤精度的烧结网进行了透水和透油试验,从中发现过滤精度与流体阻力之间的关系。丝网滤材透液率和分离液体的粘度和滤材表面浸润性能及两侧的压差有关。     

氯化N-苄基-4-乙烯基吡啶聚合物的抗菌活性

氯化N-烷基-4-乙烯基吡啶聚合物,简称可溶性PVP,是一类具有高活性、低毒性和诸多潜在的特殊用途的季铵盐抗菌材料.本研究对聚-N-苄基乙烯基吡啶进行了合成与提纯,并对其在不同物理化学条件下抗菌性能差异进行了研究,结果表明温度、溶液条件等因素的变化对于样品的抗菌性能有重大影响.     

乳化剂SP-80合成动力学影响因素的探讨

考察乳化剂SP-80合成中相关动力学影响因素,以产品的乳化能力为考核指标,通过正交试验法优选出最佳工艺条件:醇酸比(摩尔比)为1∶1.3,山梨醇脱水温度为110~130℃,山梨醇脱水时间为2.0~2.5h,真空度为3.0kPa,酯化反应温度为200~210℃,酯化反应时间为3.5~4.5h,催化剂用量为0.30%~0.40%。     

Integrated fertilizer requirements of groundnut-wheat cropping system

Investigations were carried out in a long term field experiment from 1976 to 1982, on a loamy sand soil to find out the fertilizer requirements of groundnut and wheat grown in fixed rotation. Application of 26 kgP/ha to wheat alone was found to be sufficient for both wheat and succeeding groundnut. Application of phosphorus to both wheat and groundnut did not result in extra beneficial effect over P application to wheat alone. However, application of 26 kg P/ha to groundnut alone was not sufficient for succeeding wheat. There was no response from K application (25 kg K/ha) in either of these two crops. Increasing the dose of N from 50–150 kg/ha to wheat significantly increased the grain yield of wheat but the pod yield of succeeding groundnut were markedly lowered. Response of wheat to 150 kg N/ha was more marked when P was also applied to wheat and response was less when P was applied to preceding groundnut alone. Zinc application at 6.25 kg/ha to wheat alone resulted in significant increase in grain yield of wheat and pod yield of succeeding groundnut.     

塑料滚塑制品缺陷分析及解决方案

简要介绍了旋转滚塑成型的方法和用途,指出了研究并解决滚塑制品缺陷的目的和意义。通过对滚塑制品较常见的几种缺陷的形成原因进行分析,从制品原材料、模具结构设计、滚塑成型工艺等方面提出了旋转滚塑成型的基本要求,同时提出了为获得高质量滚塑制品时应避免或减少各种缺陷的解决方案。     

高分子和盐对3-十二烷氧基-2-羟丙基三甲基溴化铵泡沫性能的影响

测定了3-十二烷氧基-2-羟丙基三甲基溴化铵(C12TAB)在PVP、PEG和溴化钠存在下的泡沫性能。结果表明：含量相同时，C12TAB／NaBr混合体系的起泡性能高于C12TAB／高分子体系，而稳泡性能低于后者。含量相同的C12TAB／高分子体系，PVP对C12TAB的影响好于PEG。     

空间资源索引与top-k查询研究

以空间资源索引结构R-tree为基础, 考虑人们对空间资源能力指标的要求, 利用道路网络模型进行空间距离的计算, 提出了一种包含能力维度信息的空间资源索引结构和top-k查询算法, 并与传统遍历算法进行对比实验, 验证了查询算法的有效性。