Microwave Extraction of V A,V D,V E from Pre mixed Feed and the Comparison with Other Extraction Methods

以甲醇为溶剂，用微波成功地萃取了饲料添加剂中的维生素A、d、E。与常规的搅拌萃取、超声波萃取方式比较，微波萃取具有速度快、萃取效率高等优点。V A, V D, V E were successfully extracted from pre mixed feed by microwave technique using methanol as solvent.Compared with conventional agitation extraction and ultrasound extration, microwave extraction has the advantages of being fast and efficient.福建省自然科学基

Distribution of dimethylsulfide of Xiamen sea surface water in spring

采用固相微萃取(SPME) 气相色谱法(GC)测定了厦门海域20个站位表层海水中DMS二甲基硫的含量,并对其分布进行分析。结果表明,厦门海域DMS含量在0 65～40 69nmol·L-1,平均浓度为12 83nmol·L-1。其中,西海域的含量最高,东海域次之,同安湾最低。与其它海域海水中DMS浓度比较,厦门海域DMS含量较高,浓度变化范围大,与叶绿素a浓度及表层水温、盐度之间无明显的相关关系。Dimethylsulfide (DMS) in surface seawater samples collected at 20 stations in the Xiamen sea area were analyzed with SPME-GC method. The results showed that the DMS concentrations varied from 0.65 to 40.69 nmol·L~(-1) with an average of 12.83 nmol·L~(-1). The concentration was the highest in Xiamen Western sea area, while was lower in Eastern sea area and the lowest in Tong'an Bay. Comparation with other sea areas, DMS concentration in Xiamen sea was higher, with the large variation. There were no clear relationships DMS with chlorophyll a, temperature and salty in Xiamen sea.国家自然科学基金(20077022);; 教育部重点课题(教技司2000第156号

关于建立证人宣誓制度的理论研究及其规则设计

引言根据法律的有关规定,任何知悉案件情况的人都可以作为证人,并负有出庭如实作证的义务。然而,在司法实践中,并非每个出庭作证的证人都如实作证,一方面,很多人明明了解案件的情况,但就是不愿意出庭作证;另一方面,有些人未必真的知道案件事实,却积极或勇敢地站出来为一方当事

海蜇Frizzled1基因的克隆及在无性繁殖中的表达

采用RACE技术解析了海蜇(Rhopilema esculentum)Frizzled1基因的cDNA和基因组结构:Re-Fzd1基因的全长cDNA为2387 bp,其中编码区为1761bp,编码586个氨基酸的多肽。SMART分析表明,Re-Fzd1基因具备Fzd家族共同的结构特征,包括:一个由23个氨基酸组成的信号肽,一个位于N-末端富含10个保守半胱氨酸残基的半胱氨酸富集域(CRD),一个含有7个跨膜片段的跨膜结构域,以及一个含有5个重要的磷酸化位点的C端尾巴。多序列比对表明,Re-Fzd1基因与刺胞动物贝螅(Hydra echinata)、水螅(Hydra vulgaris)、半球美螅水母(Clytia hemisphaerica)和海葵(Nematostella vectensis)Fzd1具有高度相似性,与来自脊椎动物人(Homo sapiens)、鼠(Mus musculus)、爪蟾(Xenopus laevis)和斑马鱼(Danio rerio)的Fzd1、Fzd2和Fzd7家族基因也具有较高的同源性。基于N-J法,将人、鼠、爪蟾、斑马鱼和果蝇(Drosophila melanogaster)所有Fzd家族基因系统进化分析显示,除果蝇外,所有Fzd家族成员聚类成4个类群,11个亚家族,海蜇Re-Fzd1基因首先与刺胞动物门的Fzd1聚类在一起,然后与脊椎动物Fzd1、Fzd2和Fzd7三个家族聚成一个类群,表明脊椎动物Fzd1、Fzd2和Fzd7家族可能与刺胞动物门的Fzd1起源于同一个共同祖先。Re-Fzd1基因组序列中不含有内含子。实时荧光定量PCR结果显示,Re-Fzd1基因在海蜇无性繁殖的4个发育阶段均有表达,其中,表达量最高的横裂体阶段是表达量最低的稚水母阶段的3.67倍。整体原位杂交显示,在海蜇横裂体时期,Re-Fzd1原位表达在触手、基座及发生横裂的部位。这些结果都表明,Re-Fzd1不但参与了海蜇的早期发育过程,还调控了海蜇无性繁殖的发生。国家自然科学基金项目(31372507);;鳌山科技创新计划项目(2016ASKJ02);;中央级公益性科研院所基本科研业务费专项资金项目(20603022016001

两岸货币清算汇兑机制的机遇、挑战和构想——基于海西先行先试的视角

ECFA签订之后,两岸货币的清算汇兑需求明显加大,现有的货币清算汇兑机制无法满足经济金融合作的要求。选择以海西为两岸货币清算汇兑机制建设的先行先试地区,研究海西面临的机遇和挑战,两岸货币清算汇兑机制建设势在必行。海西可率先扩大新台币兑换对象、种类,建立两岸货币兑换的定价机制;海西试点两岸贸易项下以新台币计价结算,建立两岸货币的间接清算汇兑机制;在两岸货币间接清算汇兑机制的基础上,进一步推进海西试点两岸货币直接清算汇兑机制

Kinetics of degradation of sulfonamides by Fenton process

采用fEnTOn氧化法同时降解水溶液中磺胺吡啶(SPy)、磺胺二甲基嘧啶(SMz)和磺胺甲噁唑(SMX)。系统考查了初始H2O2浓度、fE2+浓度、PH对3种磺胺类抗生素降解性能的影响。结果表明,3种磺胺抗生素被完全降解的最佳fEnTOn氧化条件是:H2O2浓度为2.0 MMOl/l,fE2+浓度为0.10 MMOl/l,PH为3.0~3.5,反应时间为20 MIn。fEnTOn试剂对3种磺胺类抗生素的降解符合一级反应动力学,速度常数为0.0318~0.2002 MIn-1。The degradability of sulfapyridine,sulfamethazine and sulfamethoxazole from aqueous solution with Fenton process was investigated using different parameters,such as pH value,H2O2 and Fe2+ concentrations.The result showed that the optimum Fenton oxidation conditions for complete removal of sulfamethoxazole,sulfapyridine and sulfamethazine,simultaneously were H2O2 concentration of 2.0 mmol/L,Fe2 +concentration of 0.10 mmol/L,pH of 3.0 to 3.5 and reaction time of 20 min.Fenton degradation followed a first-order kinetic model with reaction constant of 0.0318 to 0.2002 min- 1.福建省自然科学基金(2012J01048); 中国科学院城市环境研究所开放基金(KLUEH201306

Function and application of surrogate and internal standard in environmental sample analysis

环境样品分析结果的准确与否关系到环境质量分析的准确度 ,没有可靠的数据质量控制方法 ,数据的可靠性就无从得到保证。国际上近年来广泛应用一种适用于环境样品中有机污染物分析的数据质量控制方法 ,其关键部分是替代物和内标物的使用。分析者能够准确地进行定量 ,并清楚地知道自己的分析数据是否符合要求。本文作者从实际工作出发 ,经过大量的验证 ,确定了计算公式 ,探讨了替代物和内标物的关系、它们的作用和应用。The accuracy of environmental quality analysis depends on the accuracy of analytical data. Lack of quality control method leads to unreliable data. The core part of data quality control in advanced laboratories is the application of surrogate and internal standard. Quality control is especially suitable for trace organic analysis of environmental samples. With quality control samples the analysts can determine the target analytes accurately and make sure the data reliability. The relative equations have been derived and explained in this paper. The relationship between surrogate and internal standard has been discussed. Research examples are given to show the function and application of these quality control samples

Determination of fungicides in water with solid phase microextraction fiber coated with single-walled carbon nanotubes

利用以单壁碳纳米管为涂层的固相微萃取纤维,通过气相色谱联用方法,研究了不同试验条件对萃取效率的影响,并建立了水中百菌清、三唑酮、稻瘟灵和异菌脲4种杀菌剂的分析方法.结果表明,单壁碳纳米管固相微萃取纤维能在P H为1的条件下正常工作,对上述杀菌剂有很好的萃取能力.该方法灵敏度高,可满足环境水样的农残检测要求.Solid phase microextraction( SPME) fiber coated with single-walled carbon nanotubes( SWCNTs) was prepared.An analytical method based on SPME-GC-ECD method was established for the detection of chlorothalonil,triadimefon,isoprothiolane,iprodione in water and the effects of experimental conditions on extraction efficiency were investigated.The results showed the extraction capacity of SWCNTs fiber for those fungicides was excellent that could be used at p H as low as 1.High sensitivity of the method was able to meet the requirements of enviromental sample tests of fungicides residues.福建省教育厅资助项目(k8012012a

Simultaneous determination of tetracycline and quinolone antibiotics in environmental water samples using solid phase extraction-ultra pressure liquid chromatography coupled with tandem mass spectrometry

应用固相萃取及超高压液相色谱-质谱联用技术,建立了环境水样中4种四环素类和6种喹诺酮类抗生素的同时分析方法。样品经Hlb固相萃取柱富集、净化后用甲醇洗脱,以超高压液相色谱-串联质谱仪多反应监测(MrM)离子模式定性、定量分析。以河水和海水为基质,卡巴氧为替代物进行回收率评价,4种四环素类抗生素在加标质量浓度分别为20.0ng/l和100.0ng/l时的回收率为94.0%--117.0%,相对标准偏差为2.0%--9.7%(n=4),方法的检出限均为20.0ng/l;6种喹诺酮类抗生素在加标质量浓度分别为5.0ng/l和20.0ng/l时的回收率为63.6%--93.9%,相对标准偏差为1.6%--8.1%(n=4),方法的检出限为0.4ng/l。结果表明,所建立的方法可成功地应用于近岸海域表层环境水样中目标抗生素残留的分析。Using HLB cartridge for extraction and cleanup,a method for simultaneous determination of 4 tetracycline and 6 quinolone antibiotics in environmental water samples was developed by ultra pressure liquid chromatography coupled with tandem mass spectrometry.Using river water and sea water as matrices and carbadox as surrogate,the recoveries and relative standard deviations(RSD,n=4) were 94.0%-117.0% and 2.0%-9.7% for 4 tetracyclines at 20.0 ng/L and 100.0 ng/L spiking levels and 63.6%-93.9% and 1.6%-8.1% for 6 quinolones at 5.0 ng/L and 20.0 ng/L spiking levels,respectively.The detection limits were 20.0 ng/L for 4 tetracyclines and 0.4 ng/L for 6 quinolones.The method has been successfully applied to the survey of 10 target antibiotic residues in Jiulong River estuary,Fujian.福建省自然科学基金项目(No.2006J0140