972 resultados para 3-17-1


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本文采用表面荧光显微镜计数法和分级稀释培养技术对我国南黄海聚球蓝细菌和异养细菌在各个季节的分布特点、摄食压力的来源以及物理水文现象对其分布影响进行了研究,同时还对浮游细菌的年际变化进行了探讨。 1. 春季三个航次中聚球蓝细菌平均丰度为3.71×10E+4 cells/ml, 生物量为10.91µg C l-1;异养细菌平均丰度为3.86×10E+5 cells/ml,生物量为17.72 µg C l-1。在垂直方向上,聚球蓝细菌一直表现为中层>表层>底层,而异养细菌在每个航次中的表现都不尽相同,但总体来说仍是中上层丰度较大。 春末夏初,海区多种水团的存在导致水域水文现象复杂,其中潮汐锋、层化现象等对浮游细菌的分布产生很明显的影响。聚球藻(Synechococcus)蓝细菌生物量最大值主要分布于潮汐锋区及层化区表层和水体中层,异养细菌生物量最大值则多出现在混合区的表、底层和层化区的表层。 2. 夏季对黄海冷水团鼎盛时期的浮游细菌的生态学研究表明:(1)垂直方向上聚球蓝细菌生物量和异养细菌的表现特点不同,聚球蓝细菌生物量的分布情况是中层>表层>底层;异养细菌丰度在垂直方向上的分布状况是表层>中层>底层。(2)聚球蓝细菌对浮游植物总生物量的贡献为2~99%(平均为42.5%),异养细菌生物量与浮游植物总生物量的比值为0.05~6.37(平均为0.85)。(3)浮游细菌的分布于水体温度和盐度变化有一定关系,冷水团中的浮游细菌生物量最低。(4)小型浮游动物对聚球藻蓝细菌的捕食率为0.20~0.42/d。 3. 秋冬季节,11月份黄海沿岸流比暖水流对聚球蓝细菌分布的影响要大,聚球蓝细菌主要分布在黄海沿岸流经过的南黄海北部水域;而异养细菌的分布在此时与聚球蓝细菌的分布恰恰相反。1月份,异养细菌的分布与暖流水的入侵有很好的相关性,主要分布在暖流水的舌锋位置34°N附近;聚球蓝细菌主要分布在暖流水经过的区域33~34.5°N。 秋、冬季,海区突出的水文特征为沿岸流及黄海暖流,它们的强弱、流向及分布直接影响了浮游细菌的分布状况。 4. 南黄海聚球蓝细菌的季节变化是春季(6月)>秋季(10月)>夏季(8月)>冬季(1月),丰度在7.8×103~5.8×104 cells ml-1间;异养细菌的季节变化是夏季(8月)> 春季(6月)>秋季(10月)>冬季(1月),丰度在1.5×10E+5~7.8×10E+5 cells ml-1间。 聚球蓝细菌对浮游植物总生物量的贡献(CB/PB)在南黄海的季节变化情况是春季>秋季>夏季>冬季,平均为35.76%。异养细菌生物量对浮游植物总生物量的比值(BB/PB)的季节变化是夏季>秋季>春季>冬季,平均为61%。 浮游细菌的主要摄食者是微型浮游动物(<20 µm)和小型浮游动物(<200 µm),在不同季节摄食者表现不同。原生动物对浮游细菌的摄食率冬季高于春季。综上所述,浮游细菌在南黄海的分布主要受温度影响,随季节变化较明显;同时也受到原生动物的下行控制。同时物理场对浮游细菌的分布也有影响。

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利用AFLP标记对海带在太平洋西北沿岸的6个主要栽培品系和6个野生地理隔离种群进行遗传多样性和亲缘关系分析。通过10对选择性引物总共检测到547个位点。在品系和种群水平,多态性位点比例(P),基因多样性(H)和香农指数(I)在大连野生种群中最高(P: 59.05%; H: 0.2057; I: 0.3062),而在连江栽培品系中最低(P: 9.87%; H: 0.0331; I: 0.0497)。在物种水平(即对所有品系和种群来说),P, H 和I 的值分别是85.01%,0.1948和0.3096。以个体间的相似系数(Dice)和种群间的遗传距离为基础,用非加权类平均法(UPGMA)分别构建个体和种群间的系统树图。AMOVA分析显示,大部分的遗传变异(60.21%)存在于品系和种群间,少部分(39.79%)存在于品系或种群内。遗传分化系数GST的值是0.6226,与FST的值(0.6021)非常接近,基因流(Nm)的值是0.1515,这三个值表明种群(品系)间存在高度的遗传分化。Mantel检验发现6个野生种群的遗传距离或遗传分化与地理距离呈正相关性(相关系数分别是r=0.8870, P=0.007 和 r=0.7962, P=0.011),符合“距离隔离(isolation by distance, IBD)”模型。总体来说,种群(品系)内的遗传多样性处于低到中等水平(大连种群除外),而它们之间的遗传分化程度非常高。 用AFLP和微卫星标记对裙带菜配子体克隆单一交配组合的孢子体后代的遗传一致性进行分析。在这项研究中,建立了2个配子体克隆单一交配系(M1和M2),2个自交系(S1和S2)并采集1个野生种群(W)。11组AFLP引物总共检测到318个位点。M1, M2, S1, S2 和W的多态性位点比例分别是4.7%,0.3%,17.9%,16.4%和36.5%。M1和M2个体间的遗传相似度(95.6-100%)要高于S1和S2(87.7-98.4%)以及W(81.5-92.1%)。在微卫星分析中,用了6个位点。M1在其中的5个位点基因型一致,而在Up-AC-2B2位点显示出不同的基因型。M2在所有6个微卫星位点的基因型都一致。而S1, S2和W都在2个以上的位点检测到不同的基因型。总之,AFLP与微卫星的分析结果一致,即配子体克隆单一交配组合的孢子体后代呈现高度遗传相似性,但也存在细微的差异。 对中国羊栖菜主产区浙江省洞头县的12个羊栖菜养殖品系的重要形态特征进行了比较研究,并利用AFLP技术对一个典型养殖种群的遗传多样性进行了分析。结果显示,这12个品系在全长、全湿质量、侧枝长、侧枝湿质量、侧枝密度等方面存在显著或极显著差异(P<0.05或P<0.01)。8组AFLP引物在这个典型养殖种群中扩增出198个片段,其中多态性片段为166个,多态性位点比例为83.8%。根据个体间的遗传距离,以UPGMA法构建了个体间的系统树图,27个羊栖菜个体聚为一枝,作为对照的铜藻为另一枝。本研究从形态和DNA分子水平说明了浙江洞头羊栖菜养殖种群具有高度遗传多样性。

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本论文通过对东海内陆架浙闽沿岸泥质沉积带EC2005孔沉积物岩性、粒度、AMS14C测年、粘土矿物以及全岩矿物衍射分析、沉积物常微量元素和稀土元素分析、总碳氮以及有机碳氮分析、磁化率测试和综合研究,以EC2005孔岩芯记录为依据分析了研究区的沉积环境演化、海平面升降、浙闽沿岸流形成历史以及蕴含的古气候信息,探讨了陆源物质矿物、地球化学成分与粒度的关系。 EC2005孔岩芯自底部至41.00 m(17.3~13.1 ka BP)为末次冰消期以来的湖泊三角洲沉积序列,物质来源主要是来自湖盆流域物质的输入。随着海平面逐渐上升,海水自13.1 ka BP开始侵入研究区,自12.3 ka BP开始海水深度加大,沿岸流的地位开始显现,7.3 ka BP以来,形成了高海平面以来主要受沿岸流控制的浅海沉积。稀土元素结果显示,东海内陆架EC2005孔12.3~9.8 ka BP是以湖盆流域近源物质为主向长江物质为主转变的过渡阶段,自大约10~9.8 ka BP开始,由于海水深度的进一步加大、沿岸流作用进一步增强,长江物质对研究区的物质供给成为主导。海平面的升高以及沿岸流的形成是物质来源发生变化的重要原因。 东海内陆架泥质沉积物中全新世期间长达700 a(5.9~5.2 ka BP)的高分辨率细粒敏感组分资料揭示的东亚冬季风增强,与GRIP冰芯δ18O揭示的冷期具有良好的对应关系。5500 a BP前后东亚冬季风突然增强,与世界范围内的5500 a BP强降温事件非常一致。功率谱分析揭示出62 a和11 a的太阳活动周期以及与现代ENSO周期相似的6 a和5 a周期,因此,中全新世东亚冬季风演化可能是太阳活动以及古ENSO事件对全球气候系统的影响所致。 东海内陆架区对末次冰消期至早全新世气候回暖的记录与该时期世界性的广泛记录相一致,应该是轨道时间尺度上太阳辐射增强与ITCZ北移以及太阳活动变化综合影响的结果。东海内陆架浙-闽沿岸泥质带EC2005孔存在的4个百年时间尺度上快速沉积事件:12.3~12.1 ka BP、7.5~7.3 ka BP、5.9~5.2 ka BP和1.5~1.3 ka BP,与新仙女木事件、7.3 ka BP冷事件、第二新冰期(5.5 ka BP强降温事件)以及北大西洋1.4 ka BP浮冰事件均有良好的对应,世界范围内广泛存在的8.2 ka冷事件对本钻孔沉积也形成了一定影响。 EC2005孔磁化率变化受到多种因素的制约,如岩性粗细、早期成岩作用以及人类活动等的影响。近3.6 ka以来,磁化率的剧烈波动可能是由于人类活动影响造成的。东海内陆架EC2005孔TOC、TN和TOC/TN的大小主要受控于岩性变化。 此外,根据陆源物质粒度和矿物成分之间的关系,建立了陆源物质平均粒径与主要矿物成分含量大小的函数模型。地球化学成分与其所赋存单种矿物的相关性分析则进一步表明,陆源矿物种类和含量控制着地球化学成分及其含量,矿物种类和含量对地球化学成分的控制是决定性的,而粒度对元素(化学成分)的“控制”实际上是由于不同粒度的矿物组分不同而造成。

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本文研究了16口虾塘的饲料投喂量、水位、盐度、透明度、水温、pH、溶解氧浓度、NH3-N浓度、水色、对虾体长及浮游植物的种类和数量等水体理化因子和生物因子的变化。经过统计分析结果如下: 在养殖前4个月饲料的日平均投喂量基本上呈一个倒“U”型。即随着养殖时间的推移,饲料日平均投喂量逐渐增大,到养殖60 d左右,饲料日平均投喂量达到了最大值,然后进入一个平台期,平台期大约维持30 d左右,随后饲料日平均投喂量逐渐减少。在120 d~130 d饲料日平均投喂量降到最低点后又逐渐回升。 水位平均值变化趋势基本相同,均为前浅后深,即随着养殖时间的推移养殖水位平均值逐渐加深 。 盐度变化趋势基本相同,均为前低后高,即随着养殖时间的推移养殖水体盐度逐渐升高。 透明度的总体变化趋势为:早上透明度比下午大,前期透明度比后期大。 水温基本上是随着养殖时间的推移而逐渐下降。6:30的水温比17:30的水温低。且6:30水温与17:30水温基本上呈平行趋势。 pH变化的总体趋势为:前期较高,随着养殖时间的推移pH逐渐下降,到中期(90d左右)pH降到最低点,尔后又逐渐上升,略呈“V”字形。早上的pH比下午的低。且早上的pH与下午的pH基本上呈平行趋势,间或有较大波动。 6:30时溶解氧浓度的平均值随着养殖时间的推移而逐渐增高。17:30时溶解氧浓度的平均值在整个养殖过程中比较平稳。同时,17:30时溶解氧浓度的平均值高于6:30,养殖前期(前90d)这种趋势更明显。 NH3-N浓度的平均值随着养殖时间的推移而逐渐增高。在养殖后期NH3-N浓度的波动较大。同时,养殖过程中17:30时NH3-N浓度的平均值高于6:30。 6:30时出现9~21号水色,它们出现的比例分别为:9号占0.1%,10号占0.3%,11号占1.1%, 12号0.6%,13号1.5%,14号占3.7%,15号占7.1%,16号占17.5%,17号占22.0%,18号占15.9%,19号占13.7%,20号10.9%,21号占5.8%;17:30时出现11~21号水色,它们出现的比例分别为11号占0.1%, 12号占0.3%,13号占1.2%,14号占4.0%,15号占6.0%,16号占17.8%,17号占24.7%,18号占18.1%,19号占11.8%,20号占9.7%,21号5.7%。 在11种典型水色中共检出浮游植物67种。其中11号水色检出16种,优势种为诺马斜纹藻(占总数47.1%)和菱形海线藻(占总数29.8%)。12号水色共检出16种,优势种为原甲藻(占总数40.85%)和圆筛藻(占总数20.73%)。13号水色共检出16种,优势种为颤藻(占总数45.58%)。14号水色共检出18种,优势种为拟货币直链藻(占总数56.73%)和膝沟藻(占总数12.87%)。15号水色共检出18种,优势种为诺马斜纹藻(占总数64.76%)。16号水色共检出16种,优势种为拟货币直链藻(占总数69.93%)。17号水色共检出14种,优势种为诺马斜纹藻(占总数62.56%)和膝沟藻(占总数15.76%)。18号水色共检出21种,优势种为拟货币直链藻(占总数71.19%)。19号水色共检出18种,优势种为圆筛藻(占总数94.99%)。20号水色共检出18种,优势种为圆筛藻(占总数87.14%)。21号水色共检出15种,优势种为拟货币直链藻(占总数59.80%)和萎软几内亚藻(占总数17.57%)。 相关分析结果表明高位池理化因子中对水色的主要影响因素:17:30PH值、养殖生物量、17:30NH3-N、17:30 透明度、水交换量。 对体长的主要影响因素为 6:30溶解氧、水交换量、17:30水色、饲料投喂量、盐度、17:30透明度、17:30水温、6:30NH3-N。 对对虾本身生物学形状对体重的影响研究表明体长、头胸甲长、胸宽、额剑下缘刺数目对体重的通径系数达到显著水平,它们是直接影响体重的重要指标,其中体长对体重的直接影响(0.428**)最大,是影响体重的最主要因素,其次为头胸甲长(0.290**)和胸宽(0.245**),额剑下缘刺数对体重的直接影响(0.070*)较小;胸高与体重的相关程度很大(0.7923),但它与额剑上缘刺数对体重的直接影响都非常小,主要通过其他性状间接影响活体重,是影响体重的次要因素。

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Two field studies were conducted to measure pigments in the Southern Yellow Sea (SYS) and the northern East China Sea (NECS) in April (spring) and September (autumn) to evaluate the distribution pattern of phytoplankton stock (Chl a concentration) and the impact of hydrological features such as water mass, mixing and tidal front on these patterns. The results indicated that the Chl a concentration was 2.43 +/- 2.64 (Mean +/- SD) mg m(-3) in April (range, 0.35 to 17.02 mg m(-3)) and 1.75 +/- 3.10 mg m(-3) in September (from 0.07 to 36.54 mg m(-3)) in 2003. Additionally, four areas with higher Chl a concentrations were observed in the surface water in April, while two were observed in September, and these areas were located within or near the point at which different water masses converged (temperature front area). The distribution pattern of Chl a was generally consistent between onshore and offshore stations at different depths in April and September. Specifically, higher Chl a concentrations were observed along the coastal line in September, which consisted of a mixing area and a tidal front area, although the distributional pattern of Chl a concentrations varied along transects in April. The maximum Chl a concentration at each station was observed in the surface and subsurface layer (0-10 m) for onshore stations and the thermocline layer (10-30 m) for offshore stations in September, while the greatest concentrations were generally observed in surface and subsurface water (0-10 m) in April. The formation of the Chl a distributional pattern in the SYS and NECS and its relationship with possible influencing factors is also discussed. Although physical forces had a close relationship with Chl a distribution, more data are required to clearly and comprehensively elucidate the spatial pattern dynamics of Chl a in the SYS and NECS.

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The inventories of nutrients in the surface water and large phytoplankton( > 69 pm) were analyzed from the data set of JERS ecological database about a typical coastal waters, the Jiaozhou Bay, China, from 1960s for N, P and from 1980s; for Si. By examining long-term changes of nutrient concentration, calculating stoichiometric balance, and comparing diatom composition, Si limitation of diatom production was found to be more possible. The possibility of Si limitation was from 37% in 1980s to 50% in 1990s. Jiaozhou Bay ecosystem is becoming serious eutrophication, with notable increase of NO2-N, NO3-N and NH4-N from 0.1417 mumol/L, 0.5414 mumol/L, 1.7222 mumol/L in 1960s to 0.9551 mumol/L, 3.001 mumol/L, 8.0359 mumol/L in late 1990s respectively and prominent decrease of Si from 4.2614 mumol/L in 1980s to 1.5861 mumol/L in late 1990s; the nutrient structure is controlled by nitrogen; the main limiting nutrient is probably silicon; because of the Si limitation the phytoplankton community structure has changed drastically.

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Based on 1997-1998 field investigations in the Changjiang river mouth, rain sampling from the river's upper reaches to the mouth, historical data, and relevant literature, the various sources of Total Nitrogen (TN) and Dissolved Inorganic Nitrogen (DIN) in the Changjiang river catchment and N transport in the Changjiang river mouth were estimated. The export fluxes of various form of were mainly controlled by the river runoff, and the export fluxes of NO3-N, DIN and TN in 1998 (an especially heavy flood year) were 1438 103 tonnes (t) yr(-1) or 795.1 kg km(-2) yr(-1) 1746 10(3) t yr(-1) or 965.4 kg km(-2) yr(-1) and 2849 10(3) t yr(-1) or 1575.3 kg km(-2) yr(-1), respectively. The TN and DIN in the Changjiang river came mainly from precipitation, agricultural nonpoint sources, N lost from fertilizer and soil, and point sources of industrial waste and residential sewage discharge, which were about 56.2% and 62.3%, 15.4% and 18.5%, 17.1% and 14.4%, respectively, of the N outflow at the Changjiang river mouth; maximum transport being in the middle reaches.

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The title compound 1-(4,5-dihydro-3-phenylpyridine-1-yl)-2-(1H-1,2,4-triazole-1-yl)ethyl ketone (DTE) was synthesized and its inhibiting action on the corrosion of mild steel in 1 M hydrochloric acid solutions was investigated by means of weight loss, potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and scanning electronic microscope (SEM). Results obtained revealed that DIE performed excellently as a corrosion inhibitor for mild steel in 1 M hydrochloric acid media and its efficiency attains more than 90.9% at 1.0 x 10(-3) M at 298 K. Polarization curves indicated that the inhibitor behave mainly as mixed-type inhibitor. EIS showed that the charge transfer controls the corrosion process in the uninhibited and inhibited solutions. Adsorption of the inhibitor on the mild steel surface followed Langmuir adsorption isotherm. And the values of the free energy of adsorption Delta G(ads) indicated that the adsorption of DTE molecule was a spontaneous process and was typical of chemisorption. (c) 2008 Elsevier B.V. All rights reserved.

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采用水蒸气蒸馏法提取了冷蒿挥发油,气相色谱-质谱联用结合计算机检索对其化学成分进行了分析和鉴定,共分离出106个峰,确定了101种化合物,它们主要是二甲基-甲撑基环庚(17.67%)、3,3,6-三甲基-1,5-庚二烯醇-2(16.40%)、3,3,6-三甲基-1,4-庚二烯醇-6(8.55%)、桉树脑(5.57%)、3,7-二甲-基2,6-辛二烯醇-1(3.85%)、神圣亚麻三烯(3.73%)、1-甲基-3-异丙基苯(3.26%)、桥环[2,2,1]萜烯(2.91%)、樟脑(2.26%)、香叶烯(2.20%),以上10种化合物占挥发油总量的66.40%。

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研究3种药用植物叶片的光合色素含量、叶表光强和叶温以及叶绿素荧光参数的日变化进程。结果表明:麻花艽的单位鲜重叶绿素和类胡萝卜素含量最高,唐古特山莨菪和鸡爪大黄的叶绿素和类胡萝卜素没有显著差异。3种植物的q_p的日进程与光强和叶温的日变化表明植物在1 d中都在进行过剩激发能的耗散,对光合机构起到一定的保护作用。

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研究两面针Zanthoxylum nitidum.(Roxb.)DC根部乙醇提取物中的化学成分.采用硅胶柱层析方法进行分离和纯化,通过波谱分析鉴定分离得到的化合物的结构.共鉴定7种香豆素成分及2种其它类型成分,其中6种香豆素前文已作过报道.本文主要介绍三种化学成分即β-谷甾醇(1),5-methoxymarmesin(2),β-香树素(3).其中5-methoxymarmesin为首次从该植物中分离得到的化合物.

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用1991~1993年在高寒草甸地区植被生育期测定的土壤水分资料,联系土壤水分平衡方程,讨论高寒草甸植被生育期的耗水量和耗水规律的特征,结果表明,草甸地区植被生育期5月20日~9月15日,3年平均耗水量约为361.0mm;全年牧草地上净初级生物量与耗水量具有一定的相关性;植被生育期内气温、降水的协调配合能提高牧草地上净初级生物量。5~9月,植被耗水量变化量单峰型曲线,3年平均表明,7月耗水量最高,5月最低。

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对西宁市郊主要公路两侧的土壤和植物中的重金属铅含量采用原子吸收光谱进行了测定。结果表明,土壤和植物中铅污染都较严重。铅的含量比清洁对照区高:土壤2.7—4.1倍,杨树枝叶3.0—4.1倍,小麦青苗3.0-3.7倍,蔬菜1.5—2.3倍。土壤、树木和农作物在距路边80—100m处铅含量通常降到当地背景水平。

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A high performance capillary electrophoresis method with diode array detector detection for the determination of five bioactive ingredients in Tibetan medicine Elsholtzia, namely quercetin, rutin, saussurenoside, kaempferol, and oleanolic acid, has been developed. The effects of several factors, such as the acidity, concentration of running buffer, separation voltage, temperature, and SDS concentration were investigated. The optimal conditions were 44 mmol/L boric acid running buffer (pH 8.5), 45 mmol/L SDS, 16 KV voltage, 20 degrees C, and 10.0% (V/V) of acetonitrile. Under the optimum conditions, five components could be separated with a good baseline resolution within 17 min. The calibration curves showed good linear relationship over the concentration range of 5 x 10(-4)similar to 0.1 mg/mL for quercetin, rutin, saussurenoside, kaempferol, and 1 x 10(-3) similar to 0.1 mg/mL for oleanolic acid. The average recoveries of the method and RSD were ( 99.2%, 3.2%) for quercetin, (102.1%, 2.1%) for rutin, (99.4%, 1.5%) for saussurenoside, (98.9%, 1.8%) for kaempferol, and (99.0%, 2.9%) for oleanolic acid, respectively. The detection limits (S/N = 3) were 1.1 x 10(-4) mg/mL for quercetin, 2.6 x 10(-4) mg/mL for rutin, 1.8 x 10(-4) mg/mL for saussurenoside, 2.9 x 10(-4) mg/mL for kaempferol, and 6.3 x 10(-4) mg/mL for oleanolic acid, respectively. The method was simple, rapid, and reproducible and could be applied for the determination of quercetin, rutin, saussurenoside, kaempferol, and oleanolic acid in Tibetan medicine Elsholtzia, and the assay results were satisfactory.

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A pre-column derivatization method for the sensitive determination of amines using a labeling reagent 2-(11H-benzo[a]-carbazol-11-yl) ethyl chloroformate (BCEC-Cl) followed by high-performance, liquid chromatography with fluorescence detection has been developed. Identification of derivatives was carried out by LC/APCI/MS in positive-ion mode. The chromophore of 1,2-benzo-3,4-dihydrocarbazole-9-ethyl chloroformate (BCEOC-Cl) reagent was replaced by 2-(11H-benzo[a]-carbazol-11-yl) ethyl functional group, which resulted in a sensitive fluorescence derivatizing reagent BCEC-Cl. BCEC-Cl could easily and quickly label amines. Derivatives were stable enough to be efficiently analyzed by HPLC and showed an intense protonated molecular ion corresponding m/z [M+ H](+) under APCI/MS in positive-ion mode. The collision-induced dissociation of the protonated molecular ion formed characteristic fragment ions at m/z 261.8 and m/z 243.8 corresponding to the cleavages of CH2O-CO and CH2-OCO bonds. Studies on derivatization demonstrated excellent derivative yields over the pH 9.0-10.0. Maximal yields close to 100% were observed with three- to four-fold molar reagent excess. In addition, the detection responses for BCEC-derivatives were compared to those obtained using 1,2-benzo-3,4-dihydrocarbazole-9-ethyl chloroformate (BCEOC-Cl) and 9-fluorenyl methylchloroformate, (FMOC-Cl) as labeling reagents. The ratios I-BCEC/I-BCEOC = 1.94-2.17 and I-BCEC/I-FMOC = 1.04-2.19 for fluorescent (FL) responses (here, I was relative fluorescence intensity). Separation of the derivatized amines had been optimized on reversed-phase Eclipse XDB-C-8 column. Detection limits calculated from 0.50 pmol injection, at a signal-to-noise ratio of 3, were 1.77-14.4 fmol. The relative standard deviations for within-day determination (n = 11) were 1.84-2.89% for the tested amines. The mean intra- and inter-assay precision for all amines levels were < 3.64% and 2.52%, respectively. The mean recoveries ranged from 96.6% to 107.1% with their standard deviations in the range of 0.8-2.7. Excellent linear responses were observed with coefficients of > 0.9996. (C) 2006 Elsevier B.V. All rights reserved.