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1.
水产品中多氯联苯残留量的气相色谱法测定   总被引:4,自引:0,他引:4  
研究并建立了水产品中的7种多氯联苯残留的气相色谱检测方法,用该方法对鱼、虾、贝、蟹、甲鱼等多种水产动物中多氯联苯的残留量进行了分析测定。结果表明,7种多氯联苯的峰面积与其质量浓度在1.0~200ng/mL范围内呈线性关系,相关系数均大于0.999。鳕鱼和牡蛎样品中添加1.0ng/g的多氯联苯标准液时,多氯联苯的回收率为81.33%~85.33%;相对标准偏差为7.33%~9.21%。方法的测定低限为0.3ng/g。另外,通过优化前处理方法,使用硅胶净化柱,缩短了样品的前处理时间,减少了试剂消耗,提高了回收率。  相似文献   

2.
皮状丝孢酵母利用大米草水解液发酵生产微生物油脂   总被引:4,自引:0,他引:4  
研究了产油酵母菌皮状丝孢酵母(Trichosporon cutaneum)利用经过简单脱毒处理的大米草水解液,直接发酵生产微生物油脂。首先分别用1%、2%、4%和6%稀硫酸,在122℃水解大米草,大米草/硫酸(固/液比)为10%。结果表明,在6%的酸浓度下水解40rain后总还原糖含量最高。而1%稀硫酸在140℃下水解大米草,2.8h后,水解液中葡萄糖产量达到最高14.2g/L。然后将该条件下大米草水解液冷冻干燥浓缩为不同的倍数,作为皮状丝孢酵母菌的发酵培养基,水解液浓缩倍数为4.0时,产油量最高达6.0g/L。为高效利用大米草,将大米草开发为一种能源植物,提供了新的途径。  相似文献   

3.
采用单因子实验设计方法,进行了饲料中添加维生素C对花鲈幼鱼生长(增重率、存活率、特定生长率、饲料效率)、免疫反应(血清中溶菌酶活性和血清总补体活性)和组织中维生素C积累量影响的研究。结果表明,随着饲料中维生素C添加量由0提高到98.9mg/kg,花鲈的增重率和特定生长率显著提高。以特定生长率为指标,花鲈最佳生长性能的饲料维生素C添加量为103.0mg/kg左右;饲料中维生素C添加量在0-98.9mg/kg时,花鲈幼鱼肌肉和肝脏中维生素C的积累量随饲料中维生素C的增加而显著增加(P〈0.05),花鲈幼鱼获得最大肝脏和肌肉中维生素C的积累量时,饲料中维生素C最低添加量为97.2mg/kg和105.0mg/kg;花鲈幼鱼血清溶菌酶和总补体活性随着维生素C添加量的增加而显著升高,维生素C添加量达到396.4mg/kg时,血清溶菌酶和总补体活性较高。综上所述,花鲈生长和免疫的维生素C适宜添加量为400mg/kg左右。  相似文献   

4.
用GC/MS法分析比较了紫菜粉、小球藻、酵母、Banta液(牛粪1.5g+干稻草2g+沃土20g+水1000cm3)4种食物条件下蚤状潘的脂肪酸组成.结果表明:4种食物培养下,蚤状潘的总脂含量依次为39.80、60.10、44.60、52.30mg/g.一共检测出脂肪酸14种,其中8种饱和脂肪酸(SFA),2种单不饱和脂肪酸(MUFA),4种多不饱和脂肪酸(PUFA).紫菜粉培养组与小球藻组PUFA含量显著高于酵母组和Banta液组(P〈0.05),占总脂肪酸的1/3以上,酵母组MUFA质量分数最高(P〈0.05),达55.73%,Banta液组以SFA质量分数最高(P〈0.05),为52.45%.其中紫菜粉组的PUFA中缺乏C18:3,但C20:5(EPA)和C20:4(AA)质量分数高达22.67%和9.02%是小球藻组的1.6倍和4.5倍(P〈0.05),而且EPA和AA的实际含量也显著高于小球藻组(P〈0.05),达到9.02mg/g和3.59mg/g;比较得出,紫菜粉培养组的20碳以上必需不饱和脂肪酸含量丰富,明显高于其他3组.本实验证实蚤状潘的脂肪酸组成与食物脂肪酸成正相关.分析认为,用紫菜粉培养枝角类用于海水育苗会取得更佳的营养效果.  相似文献   

5.
采用Comell方法研究了初始重为(2.0±0.1)g的重口裂腹鱼幼鱼日粮中常量营养物质的适宜需求量。日粮中蛋白质、脂肪和碳水化合物梯度变化范围分别为33%-51%、3%-18%和24%-33%,试验周期为60d。试验结果表明,除日粮蛋白质33%组鱼成活率明显下降外(P〈0.05),其它试验日粮中3种常量营养物质含量对重口裂腹鱼幼鱼成活率没有显著影响(P〉0.05)。当日粮蛋白质水平≤45%时,其特定生长率随着日粮蛋白质水平上升而明显增加;当日粮蛋白质水平在33%-36%时,重口裂腹鱼的特定生长率显著降低(P〈0.05)。除12%日粮脂肪组试验鱼外,9%日粮脂肪组试验鱼的特定生长率显著性高于其它脂肪水平日粮组(P〈0.05),但当日粮中脂肪含量≥15%后,重口裂腹鱼鱼体脂肪含量显著上升(P〈0.05),肝细胞脂肪变性明显。日粮中不同的碳水化合物水平对重口裂腹鱼特定生长率没有显著影响(P〉0.05),但当日粮中碳水化合物为33%时,鱼体糖原含量显著增加(P〈0.05)。试验表明,重口裂腹鱼幼鱼日粮蛋白质、脂肪和碳水化合物3种常量营养物质的适宜需求量分别为45%、9%和≤30%。日粮总能为19.0MJ/kg,蛋白质能量比(P/E)为23mg/J。  相似文献   

6.
原子荧光光谱法测定天然水体中的Se(IV)   总被引:3,自引:0,他引:3       下载免费PDF全文
姚庆祯  张经 《海洋科学》2003,27(4):63-67
采用氢化物—原子荧光光谱法(HG-AFS),在1mol/L HCl介质中用KBH4作还原剂测定天然水体中痕量Se(IV)。利用正交实验对实验条件进行了优化选择,在确定的条件下,方法的检出限为0.06nmol/L,对Se(IV)含量为0.51nmol/L和1.14nmol/L的样品分析精密度为3.9%和3.5%,方法的回收率为96%-105%,线性范围为0.06—250nmol/L。在不同介质中工作曲线的变动范围小于5%。  相似文献   

7.
黑鱾血液的生理生化指标研究   总被引:2,自引:0,他引:2  
孙敏  徐善良  唐道军 《台湾海峡》2009,28(4):482-487
本文采用F-820半自动血细胞分析仪和全自动生化分析仪,对黑纪的血液常规指标及血清中的17项生化指标进行了分析测定,并用Wright’s染色法制作血涂片对白细胞进行分类计数.结果表明:(1)黑纪的血红细胞数量为(2.49±0.47)×10^12个/dm^3;白细胞数量为(1.08±0.21)×10^11个/dm^3;在白细胞中以嗜中性粒细胞数量最多,占52.42%±4.67%,其次为淋巴细胞,占25.72%±2.88%;单核细胞体积最大,占总数的3.27%±0.62%.(2)黑纪红细胞脆性大,抗性差,在0.65%~0.70%的NaCl溶液中开始溶血,在0.50%~0.55%的NaCl溶液中完全溶血.(3)黑纪的血红蛋白(HGB)为109.11±15.72g/dm^3,高于一般鱼类,与其较强的耐低氧生理能力相适应.(4)血清中血糖浓度为4.72±1.35mmol/dm^3,明显低于凶猛肉食性鱼类,与其岛礁性生态习性和杂食性相吻合.(5)雌雄鱼的乳酸脱氢酶分别为332.67±188.48U/dm^3和905.66±257.85U/dm^3,雌鱼显著高于雄鱼,可能与繁殖活动相关.  相似文献   

8.
利用老化虾塘进行斑节对虾与锯缘青蟹混养试验   总被引:1,自引:0,他引:1  
在老化虾塘中进行斑节对虾(Penaeus monadom Fabricus)与锯缘青蟹(Scyll serrata)混养试验,结果如下:斑节对虾的产量为1225kg/hm2,养成存活率为65.3%:锯缘青蟹的产量为422.5kg/hm2,存活率为40.2%;纯收入42105元/hm2,投入产出比达到1:2,取得了较好的经济效益。  相似文献   

9.
生物群、沉积物和有机地球化学变化显示,古新统-始新统(P/E)界线全球事件在西藏南部定日(东特提期残留海低纬度浅水)地区存在明显响应:古新统宗浦组顶部有孔虫动物群的属、种绝灭率分别为87%和94%,始新统遮普惹组底部有孔虫属、种新生率分别达80%和69%;岩层以(生物滩相)薄-中层向厚层-块状生物灰岩转化,泥质含量增加;典型生物标志经合物参数变化明显,Pr/17比值平均从0.365增加到0.86,Ph/18由0.56变为0.92,β/17由12.843剧增到123.17,γ/17由2.46突变为29.5。结合西藏及邻区岩相分布、接触关系后认为,这种全球地质事件的响应在研究区可能是一种古海洋事件,可能由大洋环流(古水团)变化引起。  相似文献   

10.
针对高30断块砂岩油藏,筛选和评价了表面活性剂/聚合物(S/P)二元复合驱油体系。结果表明,表面活性剂CDS-1在有效浓度(0.025%~0.300%)低而宽的范围内,体系与原油的界面张力可降到能大幅度提高驱油效率的10^-2mN/m数量级;当疏水缔合聚合物HNT201—3浓度为1250mg/L、CDS-1浓度为0.05%时,体系在地层条件下的表现黏度可达72.37mPa·s。在模拟油层渗透率及非均质变异系数的岩心上,注入0.30PV二元复合体系及0.10Pv聚合物保护段塞时,可比水驱提高采收率20.91%OOIP。  相似文献   

11.
目的:建立中药舒心片中丹酚酸B含量的测定方法。方法:采用高效液相色谱法(HPLC)测定舒心片中丹酚酸B的含量,色谱柱为Agilent TC-C18(2)色谱柱(4.6 mm×250 mm,5 μm),以乙腈-0.1%的磷酸溶液(25∶75)为流动相;检测波长为286 nm;柱温为25℃;流速为1.0 ml/min。结果:供试品和对照品溶液中丹酚酸B与他峰分离度良好;在0.050~1.642 μg之间丹酚酸B呈良好线性关系,R=0.9993,丹酚酸B平均加样回收率为97.58%,RSD=0.25%。结论:经方法学验证,本法可用于舒心片的质量控制。  相似文献   

12.
目的:研究补肺养心汤对冠心病心力衰竭患者中医证候及心功能的影响。方法:将94 例冠心病心力衰竭患者按随机数字表法分为治疗组和对照组,每组各47 例。对照组予以螺内酯、呋塞米、阿司匹林肠溶片等常规西药治疗,治疗组在对照组基础上联合补肺养心汤治疗,2组均以4周为1个疗程,共治疗3个疗程。治疗后比较2组的中医证候(心悸、气短、胸胁作痛)积分及心功能指标左心室射血分数(LVEF)、左心室收缩末期内径(LVESD)及左心室舒张末期内径(LVEDD)变化。结果:总有效率治疗组为85.11%(40/47),高于对照组的63.83%(30/47),差异有统计学意义(P<0.05);治疗后2组患者心悸、气短、胸胁作痛等中医证候积分及LVEDD、LVESD水平较治疗前降低,LVEF水平较治疗前升高,且治疗组改善幅度较对照组更为明显(均P<0.05)。结论:补肺养心汤可有效缓解冠心病心力衰竭患者的临床症状,改善心功能,促进病情恢复。  相似文献   

13.
目的:基于网络药理学与体外细胞实验探讨复方清痹片治疗类风湿性关节炎(RA)的作用机制。方法:基于TCMID、TCMSP和DrugBank数据库筛选复方清痹片的活性成分并预测潜在活性成分靶点;基于GeneCard、OMIM等数据库筛选RA疾病靶点;明确复方清痹片活性成分与RA的共同潜在靶标;利用STRING数据库和Cytoscape软件构建蛋白质-蛋白质相互作用(PPI)网络,并通过DAVID数据库进行基因本体(GO)功能及京都基因与基因组百科全书(KEGG)通路富集分析,RT-PCR检测复方清痹片对肿瘤坏死因子(TNF-α)诱导的人类风湿性关节炎成纤维样滑膜细胞(HFLS-RA)模型白介素6(IL-6)、TNF-α、丝氨酸/苏氨酸蛋白激酶1(AKT1)和血管内皮生长因子A(VEGFA)mRNA表达的影响。结果:筛选出217种潜在活性成分以及158个潜在靶点;IL-6、TNF、AKT1、白蛋白(ALB)、VEGFA等是复方清痹片治疗RA的关键靶点;复方清痹片主要通过炎性因子、趋化因子、免疫调控等信号通路来发挥治疗RA的作用。复方清痹片能够抑制HFLS-RA增殖,下调IL-6、TNF、AKT1和VEGFA mRNA的表达,这与网络药理学预测的结果相一致。结论:本研究揭示了复方清痹片治疗RA“活性成分-靶点-通路”的复杂关系,为后续该药的临床应用提供了研究基础。  相似文献   

14.
目的:观察复方皂角刺膏外敷治疗肝癌重度癌性疼痛的临床疗效。方法:将肝癌重度癌性疼痛患者56 例随机分为治疗组和对照组,每组各28 例。对照组予以盐酸羟考酮缓释片治疗,治疗组在对照组基础上加用复方皂角刺膏外敷治疗,疗程均为7 d。观察2组的疼痛强度、使用阿片类止痛药剂量、爆发痛次数及健康状况。结果:总有效率治疗组为92.86%(26/28),对照组为71.43%(20/28),2组比较,差异有统计学意义(P<0.05)。与治疗前比较,2组治疗后数字分级法(NRS)评分、Karnofsky功能状态(KPS)评分均改善,且治疗组改善程度优于对照组(P<0.05或P<0.01)。2组治疗第1天止痛药剂量比较,差异无统计学意义(P>0.05);治疗后治疗组止痛药剂量较对照组减少(P<0.05)。治疗组爆发痛次数少于对照组(P<0.05)。结论:复方皂角刺膏外敷治疗肝癌重度癌性疼痛的镇痛效果明显,能减少阿片类止痛药剂量与爆发痛次数,提高患者生活质量。  相似文献   

15.
目的:观察三香通络饮联合苯磺酸氨氯地平片治疗老年性高血压病的临床疗效。方法:将92 例老年性高血压病患者按随机数字表法分为治疗组和对照组,每组各46 例。对照组口服苯磺酸氨氯地平片治疗,治疗组在对照组基础上加用三香通络饮治疗。比较2组的综合疗效、中医证候积分及不良反应发生情况。结果:总有效率治疗组为89.13%(41/46),对照组为60.87%(28/46),2组比较,差异有统计学意义(P<0.05);2组各项中医证候积分治疗前后组内比较,差异均有统计学意义(P<0.05),且治疗后头晕目眩、头痛、心悸、口干口苦评分组间比较,差异均有统计学意义(P<0.05);不良反应发生率治疗组为10.87%(5/46),对照组为19.57%(9/46),2组比较,差异无统计学意义(P>0.05)。结论:三香通络饮联合苯磺酸氨氯地平片治疗老年性高血压病患者的临床疗效优于单用西药治疗,且能有效减轻临床症状,值得推广。  相似文献   

16.
In order to assess the impact of deep-sea mining on the in situ benthic life, we measured the microbial standing stock and concentration of organic nutrients in the deep-sea sediments of the Central Indian Ocean Basin in the Indian pioneer area. Sediments were collected using box core and grab samples during September 1996. The total bacterial numbers ranged from 10 10 -10 11 cells per g -1 dry weight sediment. There was a marginal decrease in the number of bacteria from surface to 30 cm depth, though the subsurface section registered a higher number than did the surface. The highest numbers were encountered at depths of 4-8 cm. The retrievable number of bacteria were two orders less in comparison with the direct total counts of bacteria. An almost homogeneous distribution of bacteria, total organic carbon, living biomass, and lipids throughout the depth of cores indicates active microbial and benthic processes in the deep sea sediments. On the other hand, a uniform distribution of total counts of bacteria, carbohydrates, and total organic carbon in all the cores indicates their stable nature and suggests that they can serve as useful parameters for long-term monitoring of the area after the benthic disturbance. Further studies on temporal variability in this region would not only verify the observed norms of distribution of these variables but would also help to understand restabilization processes after the simulated benthic disturbance.  相似文献   

17.
The interdependence between the seismo-acoustic properties of a marine sediment and its geotechnical/physical parameters has been known for many years, and it has been postulated that this should allow the extraction of geotechnical information from seismic data. Though in the literature many correlations have been published for the surficial layer, there is a lack of information for greater sediment depths. In this article, a desktop study on a synthetic seafloor model illustrates how the application of published near-surface prediction equations to subsurface sediments (up to several tens of meters burial depth) can lead to spurious predictions. To test this further, acoustic and geotechnical properties were measured on a number of sediment core samples, some of which were subjected to loading in acoustically-equipped consolidation cells (oedometers) to simulate greater burial depth conditions. For low effective pressures (representing small burial depths extending to around 10 meters subsurface), the general applicability of established relationships was confirmed: the prediction of porosity, bulk density, and mean grain size from acoustic velocity and impedance appears generally possible for the investigated sedimentary environments. As effective pressure increases through, the observed relationships deviate more and more from the established ones for the near-surface area. For the samples tested in this study, in some instances increasing pressure even resulted in decreasing velocities. There are several possible explanations for this abnormal behavior, including the presence of gas, overconsolidation, or bimodal grain size distribution. The results indicate that an appropriate depth correction must be introduced into the published prediction equations in order to obtain reliable estimates of physical sediment properties for greater subsurface depths.  相似文献   

18.
海上大直径钢管桩打桩过程中,桩周土体受到强烈扰动而发生强度弱化,掌握桩周土体强度弱化规律对于准确预测打桩过程、保证工程安全具有重要意义。为研究土体强度弱化规律,开展了环剪试验模拟打桩对桩周土体的扰动,测试土体强度随剪切速率的变化规律,建立了描述土体强度弱化规律的拟合公式,引入到打桩分析软件中。研究结果表明:土体的强度折减程度不仅与土体本身的性质有关还受到土体的埋深和剪切速率的影响,埋深越深土体强度折减程度越低,剪切速率越高土体强度折减越高,在打桩分析中可采用这里推荐的线性折减方法来模拟不同深度处土体强度的折减规律。  相似文献   

19.
An acoustic inversion method using a wide-band signal and two near field receivers is proposed and applied to multiple layered seabed models including a manganese sediment. The inversion problem can be formulated into a probabilistic model comprised of signals, a forward model, and additive noise. The forward model simulates wide-band signals, such as chirp signals, and is chosen to be the source-waveletconvolution plane wave modeling method. The wavelet matching technique, using weighted least-squares fitting, estimates the sediment sound-speed and thickness on which determination of the possible numerical ranges for a priori uniform distribution is based. The genetic algorithm is applied to a global optimization problem to find a maximum a posteriori solution for determined a priori search space. Here the object function is defined by an L 2 norm of the difference between measured and modeled signals. Not only the marginal pdf but also its statistics are calculated by numerical evaluation of integrals using the samples selected during importance sampling process of the genetic algorithm.  相似文献   

20.
Specific properties of the interannual sea level variations and annual tides in the Northwestern Pacific were studied. Several tide stations were monitored. The monthly mean sea level for the year of 1995 was analyzed at each tide station. A seismic event in 1995, some tectonic activity around the subject area, and the Kuroshio (the oceanic western boundary current) may possibly contaminate results which would have occurred from the astronomical annual tide alone.  相似文献   

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