基于切向超滤技术的胶体有机碳和无机氮分离及物源初探

利用切向超滤技术对九龙江口天然水体中胶体相(1 kDa～0. 45μm)、真溶解相(<1 kDa)和\"溶解相\"(<0. 45μm)的溶解有机碳和无机氮进行了分离与提取,初步探讨了水环境因子对其理化特性的影响机制,进而探讨了它们的来源和转化.结果表明,切向超滤过程的膜空白和质量平衡符合技术要求;溶解有机碳、亚硝酸盐氮、氨氮、硝酸盐氮和无机氮存在形式以真溶液相(<1 kDa)为主,其在胶体相中的质量浓度分别为0. 207～0. 810 mg/dm3、0. 001～1. 870μg/dm3、ND～2. 08μg/dm3、0. 62～79. 30μg/dm3和1. 07～81. 10μg/dm3;胶体态溶解有机碳(COC)含量主要受陆源输入控制.国家海洋局海洋公益性行业科研专项资助项目(201505034-4);;福建省科学技术厅公益专项资助项目(2015R1003-12

EQCM and in-situ reflectance FTIR spectroscopic studies of adsorption and oxidation of methanol on Pt electrode in alkaline media

The adsorption and oxidation of methanol on Pt electrode in alkaline media have been investigated by using cyclic voltammetry, electrochemical quartz crystal microbalance (EQCM) and in-situ reflectance FTIR spectroscopy. The experimental results demonstrated that the electrooxidation of CH3OH was closely relative to solution acidity. Only one current peak of methanol oxidation in PGPS was detected at -0.09 V, which illustrated the disappearance of the second current peak due to Pt electrode passivation in alkaline media. The magnitude of the dissociative adsorbate of methanol in alkaline media is smaller than that in acidic media. The main product, such as CO2 and CO32-, was detected clearly and the reactive intermediates that were determined by FTIRS under experimental condition might be mainly HCOO- species. The EQCM studies provide quantitative results of surface mass changes during methanol oxidation, and have thrown new light in the elucidating methanol oxidation

碱性介质中甲醇在铂电极表面吸附和氧化的电化学原位FTIR反射光谱和EQCM研究

运用电化学循环伏安、原位FTIR反射光谱和石英晶体微天平(EQCM)等方法研究了碱性介质中甲醇在Pt电极表面吸附和氧化行为.结果表明:甲醇电氧化与溶液酸碱性有密切的关系.酸性介质中甲醇在Pt电极上的CV曲线有两个正向氧化峰,而碱性介质中只有一个正向氧化峰,第二个氧化峰的消失可能是由于碱性介质中Pt电极在高电位下形成高氧化态的氧物种毒化其表面引起的.碱性介质中甲醇解离吸附产物的数量比酸性介质的明显减少,对甲醇氧化的第一个氧化峰表现出更高的电催化活性.目前实验条件下,原位FTIR反射光谱检测到:碱性介质中甲醇电氧化的最终产物是CO_2和CO_3~(2-),反应中间体主要为HCOO~-物种.从电极表面质量定量变化的角度提供了甲醇反应机理的新数据

Preparation of agricultural low-cost super water absorbent

概述了合成类吸水树脂在农用上的进展,提出采用低成本且工艺成熟的水溶液法,以丙烯酸(AA)、丙烯酰胺(AM)为基体、接枝可溶性淀粉进行三元单体共聚,经钠基膨润土改性,复合引发剂、复合交联剂制备低成本、易降解的合成类吸水性树脂。经实验改进和工艺条件优化后,树脂吸去离子水倍率可达1 940.9 g/g,吸自来水899.8g/g。采用红外光谱仪、热重分析仪、扫描电镜、X射线衍射仪等分析手段对合成树脂进行了分析表征,证实了产物为淀粉、丙烯酸及丙烯酰胺的共聚物。The utilization status of the synthetic absorbent resin in agricultural applications was summarized.An improved process of three monomer copolymer system was proposed by using an aqueous solution polymerization.These three monomers are soluble starch,acrylic acid and acrylamide,which are modified by sodium bentonite,using a composite initiator and cross-linker.By improving the experiments and optimizing the process conditions,the absorption rate of the synthetic absorbent resins is up to 1 940.9 g/g in deionized water,and 899.8 g/g in tap water.In addition,the structure and performance of the synthetic absorbent resin were characterized by using infrared spectroscopy,thermal gravimetric analysis,scanning electron microscopy and X-ray diffraction,which shows that it is an copolymer of starch,acrylic acid and acrylamide

碱性介质中正丁醇在铂电极上吸附和氧化的电化学原位FTIR反射光谱和EQCM研究

运用电化学循环伏安(CV)、原位FTIR反射光谱和电化学石英晶体微天平(EQCM)等方法研究了碱性介质中正丁醇在Pt电极表面吸附和氧化行为。结果表明:正丁醇电氧化过程与溶液酸碱性有着密切的关系。酸性介质中正丁醇在Pt电极上的CV曲线有2个正向氧化峰,而碱性介质中只有1个正向氧化峰,第2个氧化峰的消失可能是由于碱性介质中Pt电极表面钝化引起的。原位FTIR反射光谱检测到,在实验条件下,碱性介质中正丁醇电氧化过程的最终产物只有丁酸根。EQCM研究还从电极表面质量定量变化的角度提供了正丁醇反应机理的新数据

Studies on the infection of freshwater crabs by Paragonimus metacercariae in Yunxiao county, Fujian

目的调查云霄县淡水蟹种类及其感染并殖吸虫囊蚴的情况。方法选取不同地理方位为调查点,捕捉各调查点的淡水溪蟹进行分类和并殖吸虫囊蚴的检查。结果全县共调查6个乡(镇)20个村,共捕捉230只蟹,查出漳州华溪蟹(n=136)、漳浦束腰蟹(n=63)和闽溪蟹(待定种)(n=31)3种;检出感染并殖吸虫蟹15只,阳性检出率为6.6%(15/230),蟹的感染指数为0.11,对福建华溪蟹和中华束腰蟹种类及分布作了修正。结论云霄县并殖吸虫宿主淡水溪蟹有3种,蟹感染并殖吸虫呈下降趋势,但仍为中度并殖吸虫疫源地。Objective To study the distribution of freshwater crabs and their infection by Paragonimus in Yunxiao county, Fujian.Methods Freshwater crabs were collected and identified.The crabs were then dissected and examined for the presence of Paragonimus metacercariae.Results Six tons of crabs from 20 villages (Yunxiao county) were collected.Three species of crabs were found , namely Sinopotamon zhangzhouense, Somanniathelphusa zhangpuensis and Minpotamon spp.The infection rate was 6.6% (15/230) for the Paragonimus, and the index of crab infection was 0.11.Species of freshwater crabs and its geographic distribution were revised for Sinopotamon fukienense and Somanniathelphusa sinensis.Conclusion Freshwater crabs are the intermediate hosts of Paragonimus in the Yunxiao county.科技部自然资源平台项目(2005DKA21104

The adsorption and oxidation of isopropanol at platinum electrode in alkaline media

The adsorption and oxidation of isopropanol in alkaline media at platinum electrode have been investigated by using electrochemical quartz crystal microbalance (EQCM) and in situ FTIR spectroscopy. The results show that there is no self-poisoning in the electrooxidation of isopropanol in alkaline media. Though no poison species, such as CO, are evidenced by in situ FTIR spectroscopy, the adsorption of isopropanol or its dissociative products on Pt surface is suggested by EQCM data. The final product of isopropanol oxidation is only acetone under experimental condition, which suggests that the oxidation of isopropanol into acetone takes place via dehydrogenation step. The EQCM studies provide quantitative results of surface mass variation and have thrown new light in the elucidating isopropanol oxidation

蒿芩清胆汤及其拆方对湿热型流感病毒性肺炎及NF-κB水平的作用研究

目的:通过观察蒿芩清胆汤及其拆方对湿热型流感病毒性肺炎及NF-κB的干预作用,以期探讨其治疗机制。方法:通过气候仓、肥甘饮食加流感病毒滴鼻感染造模成功后,蒿芩清胆汤及其拆方组以相应中药干预,比较各组肺指数、光镜下病变程度半定量、肺组织NF-κB mRNA表达水平。结果:蒿芩清胆汤及其拆方均能不同程度降低肺指数、肺部病理改变及NF-κB mRNA表达水平,其中全方效果最佳。结论:蒿芩清胆汤具有抗湿热型流感病毒性肺炎的作用,其机制可能与抑制NF-κB活化从而减少其下游炎性细胞因子分泌,截断"炎症瀑布"效应有关

Optimization of Hydrometallurgical Purification for SiO_2 in the Process of Preparing Solar-grade Silicon

考察了Hf质量分数、H2C2O4质量分数、HnO3质量分数、酸浸时间、粒径、液体质量与固体质量的比值(简称液固比,下同)等因素对混酸法提纯SIO2工艺过程的影响,利用电感耦合等离子体发射光谱仪(ICP-OES)、场发射扫描电子显微镜(SEM)进行表征。结果表明,最佳工艺条件为:W(Hf)=2%、W(H2C2O4)=3%、W(HnO3)=30%、酸浸时间4 H、粒径100~120目、液固比4∶1、酸浸温度30℃。fE、Al、CA、P杂质的去除率分别达到99.99%、14.02%、73.27%、60.00%,经混酸法处理后SIO2中杂质总量的质量分数降至1.465x10-4。As a pre-treatment unit for preparing solar-grade silicon,hydrometallurgical route could remove most metallic impurities in silicon dioxide(SiO2) and raise the yield of the final product.Acid leaching of SiO2 could reduce the cost and energy consumption of industrialized development.Combined with high purity of reducing agent,the successor process of pyrometallurgy can also achieve "continuous casting".Factors such as the mass fraction of leaching agent,time,the particle size of SiO2,and the liquid-solid ratio were investigated,and the samples were characterized by means of ICP-OES,SEM,etc.The optimal reaction conditions were as follows:w(HF)=2%,w(H2C2O4)=3%,w(HNO3)=30%,reaction time 4 h,the average size of SiO2 powder particle 100～120 mesh,the liquid-solid ratio 4∶1,and room temperature 30 ℃.It was found that the final removal rates of impurities of Fe,Al,Ca,P could reach 99.99%,14.02%,73.27%,and 60.00% respectively and the mass fraction of total amount of impurities could be reduced to 1.465×10-4

软颗粒饲料对“红膏蟹”培育生长、存活和营养成分的影响

将平均体质量(453.6±46.91)g、已交配的健康锯缘青蟹饲养在36cm×26cm×27cm塑料箱中,投喂由鲜杂鱼糜加淀粉、电解多维粉末和卡拉胶制得的软颗粒饲料,培育锯缘青蟹\"红膏蟹\"。试验结果表明,29~31d育成\"红膏蟹\";投喂软颗粒饲料的青蟹肌肉占比(59.89%~60.84%)显著低于投喂冰鲜杂鱼和贝类的青蟹(P<0.05),但培育成活率(96.9%~97.1%)、质量增加率(67.26%~69.47%)、特定增长率(1.39%/d~1.53%/d)、可食部分(65.67%~66.32%)和红膏占比(17.36%~17.68%)均显著高于投喂冰鲜杂鱼和贝类的青蟹(P<0.05);软颗粒饲料组\"红膏蟹\"肌肉中粗蛋白、脂肪和水分的含量分别为19.9%、0.8%和75.1%,生殖腺中粗蛋白、脂肪和水分含量分别为30.59%、14.50%和54.69%,肌肉和生殖腺中必需氨基酸的含量分别为5.59%和8.14%,呈味氨基酸的含量分别为6.50%和9.90%,氨基酸评分分别为71.7和100,肌肉和生殖腺中饱和脂肪酸总量分别为44.0%和49.2%,单不饱和脂肪酸总量分别为24.6%和29.2%,多不饱和脂肪酸总量分别为27.9%和15.7%;投喂软颗粒饲料提高了青蟹肌肉中粗蛋白的含量和青蟹的营养价值。福建省星火项目(2016S0055);;福建省公益性项目(2018R1037-1);;2017年宁德市现代渔业结构调整资金资助项目(宁财农指[017]65号);;宁德师范学院科研发展资金资助项目(2016FZ24