厦门沿海的砂壳纤毛虫(原生动物,纤毛门,砂壳目)

对厦门沿海6个代表性站位砂壳纤毛虫进行了为期1年的采集,共分离鉴定了27种砂壳纤毛虫,其中拟铃虫属Tintinnopsis 20种,薄铃虫属Leprotintinnus 3种,类铃虫属Codonellopsis 2种,领细壳虫属Stenosemella 1种以及网纹虫属Favella 1种。对该5属27种砂壳纤毛虫进行形态学描述,并提供了显微照片,其中侧胀拟铃虫Tintinnopsis ventricosoides Meunier,1910为中国新记录种。国家自然科学基金(91751207和41306125);;海洋公益性行业科研专项经费(201505003-3);;中海石油有限公司项目(CNOOCKJ125FZDXM00TJ001-2014,CNOOC-KJ125FZDXM00ZJ001-2014)资助~

再酯化甘油三酯型鱼油中不同结构酯的 含量及稳定性分析

再酯化甘油三酯（rTG）型鱼油是甘油三酯(TG)、甘油二酯(DG)、甘油一酯(MG)和乙酯(EE)的混合物。为了解rTG型鱼油不同结构酯的组成及其对产品稳定性的影响，采用高效液相色谱-示差折光检测器检测了来自国内外10个厂家的18个批次rTG型鱼油中不同结构油脂的含量，与天然TG型鱼油和EE型鱼油进行比较，并考察了TG含量对rTG型鱼油产品稳定性的影响。结果表明：rTG型鱼油中TG含量在52.17%~94.80%，其中只有4个批次样品高于90%，偏甘酯含量在4.96%~38.97%，EE含量在0.28%~13.10%，其中有7个批次样品EE含量超过了5%，不符合欧洲药典（EP10.3）要求；天然TG型鱼油的TG含量在97%以上，EE型鱼油的EE含量在99%以上；与TG含量低( 64.09%）的rTG型鱼油产品相比，TG含量高（90.80%）的rTG型鱼油产品酸值和过氧化值相对原料变化较小；加速氧化过程中，TG含量高的rTG型鱼油产品的酸值稳定,但TG含量低的rTG型鱼油产品酸值明显增高。rTG型鱼油产品的稳定性可能与TG含量有关，TG含量高的rTG型鱼油的稳定性比TG含量低的更好。Abstract：Re-esterified triglyceride (rTG) type fish oil is a mixture of triglycerides (TG), diglycerides (DG), monoglycerides (MG) and ethyl esters (EE). In order to learn about the distribution of different structural esters in rTG type fish oil and their effects on product stability, 18 batches of rTG type fish oil from 10 factories in domestic and abroad were collected, the contents of different structure esters were determined by HPLC-differential refractive index detector and compared to nature TG type fish oil and EE type fish oil, and effect of TG content on the stability of fish oil product was investigated. The results showed that the TG content in rTG type fish oil was 52.17%-94.80%, among which only 4 batches samples were higher than 90%. The content of partial glycerides ranged from 4.96% to 38.97%, and the EE content ranged from 028% to 13.10%, with 7 batches samples exceeding 5%, which did not meet the requirements of European Pharmacopoeia(EP10.3). The TG content in natural TG type fish oil was above 97%, and the EE content in EE type fish oil was above 99%. Compared with rTG type fish oil products with low TG content (64.09%), rTG type fish oil products with high TG content (90.80%) had relatively small changes in acid value and peroxide value compared to raw materials. During the accelerated oxidation process, the acid value of rTG type fish oil products with high TG content was stable, while the acid value of rTG type fish oil products with low TG content significantly increased. TG content may be related to the stability of rTG type fish oil, and rTG type fish oil with high TG content has better stability than rTG type fish oil with low TG content

Simultaneous determinatin of K--+, Na--+, Ca--2+, Mg--(2+) and NH--4_+ by isotachophoresis

利用18-冠6醚与k--＋，nA--＋，CA--2＋，Mg--2＋，nH_4--＋离子络合常数的不同，在等速电泳分离体系前导电解质溶液中加入适量18-冠6醚，改变各离子的有效淌度，实现了上述离子的一次性分离和同时检测。将此法应用于分析气溶胶、实际水样、矿样，测定结果与标准值基本一致。K--+, Na--+, Ca--2+, Mg--2+ and NH--4_+ were simulataneously determined by capillary isotachophoresis.The 18-crown-6 ether of 30mmol/L as complexant was added into the leading electrolyte to change the effective mobility of these ions for their separation in the capillary.The separation and determination conditions were optimized.The method has been used in the analysis of aerated solids, water samples and standard silicate mineral samples with satisfaction.The results obstained agreed well with standard val ues.The detection limits were 1.02, 1.2, 0.72, 1.38 and 2.34 ng for NH--+_4,Ca--2+,Mg--2+,Na--+ and K--+, respectively.The standard deviation was 0.026 -- 0.034 and the coefficient of variation was 0.76% -- 1.2%.国家自然科学基金;固体表面物理化学国家重点实验室资助项

中国农田的温室气体排放

中国是一个农业大国 ,拥有约 1 .33百万平方公里的农田。这些田地的种植、翻耕、施肥、灌溉等管理措施不仅长期改变着农田生态系统中的化学元素循环 ,而且给全球气候变化带来影响。农业生态系统对全球变化的影响主要是通过改变 3种温室气体 ,即二氧化碳(CO2 )、甲烷 (CH4)和氧化亚氮 (N2 O)在土壤 -大气界面的交换而实现的。为了分析多种因素(如气候、土壤质地、农作物品种及各种农田经营管理措施等 )对农业土壤释放CO2 ,CH4和N2 O的综合影响 ,一个生物地球化学过程模型 (DNDC)近年发展起来 ,用于预测这一复杂系统的动态。DNDC模型可对农业生态系统中的碳 (C)、氮 (N)循环进行计算机模拟 ,并计算农田温室气体的释放量。通过与一个地理信息系统数据库的连接 ,DNDC完成了对中国农田 1 990年温室气体排放的估算。结果表明中国农业生态系统的CO2 净排放量约 95百万吨C/年、CH4约 9.2百万吨C/年、N2 O约 1 .3百万吨N/年。根据全球增温潜势 (GWP)计算 ,中国农田释放的N2 O对全球增温的影响高于CO2 和CH4。模拟结果还发现中国农业对减缓全球温室效应的最大贡献发生在 1 980～ 2 0 0 0年间 ,在这 2 0年中 ,全国水稻田的灌溉方法由持续淹灌逐渐改为晒田间灌 ,DNDC计算的中国农田CH4的年排放量由 1 980年的 1 2百

JUNO Sensitivity on Proton Decay p→νˉK+p\to \bar\nu K^+ Searches

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this paper, the potential on searching for proton decay in $p\to \bar\nu K^+$ mode with JUNO is investigated.The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits to suppress the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar\nu K^+$ is 36.9% with a background level of 0.2 events after 10 years of data taking. The estimated sensitivity based on 200 kton-years exposure is $9.6 \times 10^{33}$ years, competitive with the current best limits on the proton lifetime in this channel

JUNO sensitivity on proton decay p → ν K + searches*

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this study, the potential of searching for proton decay in the $p\to \bar{\nu} K^+$ mode with JUNO is investigated. The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits suppression of the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar{\nu} K^+$ is 36.9% ± 4.9% with a background level of $0.2\pm 0.05({\rm syst})\pm$$0.2({\rm stat})$ events after 10 years of data collection. The estimated sensitivity based on 200 kton-years of exposure is $9.6 \times 10^{33}$ years, which is competitive with the current best limits on the proton lifetime in this channel and complements the use of different detection technologies