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61.
62.
酸溶法测定硫铁矿中的全硫 总被引:1,自引:0,他引:1
在野外地质队实验室仪器少的条件下,用酸溶的方法分析硫铁矿中全硫,简单、快速、易操作,取得良好的结果。 相似文献
63.
以双齿围沙蚕、泥鳅、黄鲫、福寿螺4种不同饵料强化培育胴长(6.50±0.20)cm的曼氏无针乌贼,用曼氏无针乌贼肝脏和卵巢的氨基酸与脂肪酸变化、亲体产卵量、卵径、卵子孵化率及其幼体成活率等指标来评价4种饵料对其繁殖性能的影响.结果表明,黄鲫组曼氏无针乌贼肝脏与卵巢中∑EAA、∑SEAA、∑EAA+SEAA、∑NEAA、∑AA含量在第一次卵巢成熟与第二次卵巢成熟时均显著高于其它投喂组(P<0.05).黄鲫组乌贼肝脏DHA/EPA在第一次卵巢成熟时显著高于其它投喂组,在第二次卵巢成熟时DHA、DHA/EPA、∑n3PUFA、∑n6PUFA、∑n3/n6PUFA都显著高于其它投喂组(P<0.05);该组乌贼第一次卵巢成熟卵巢DHA、∑n3PUFA、∑n6PUFA、∑n3/n6PUFA及在第二次卵巢成熟时卵巢DHA、DHA/EPA、∑n3PUFA、∑n3/n6PUFA均显著高于其它投喂组(P<0.05),该组第二次卵巢成熟时∑n6PUFA百分含量与沙蚕组无显著差异(P>0.05).产卵量多少顺序为黄鲫组>沙蚕组>泥鳅组>福寿螺组(P<0.05);孵化率高低顺序为黄鲫组>福寿螺组>泥鳅组>沙蚕组(P<0.05);所产卵子平均直径大小顺序为黄鲫组>泥鳅组>沙蚕组>福寿螺组(P<0.05);幼体成活率高低顺序为黄鲫组>泥鳅组>沙蚕组、福寿螺组(P<0.05).各指标吻合程度高. 相似文献
64.
长江下游江段铜鱼肌肉营养成分分析 总被引:7,自引:0,他引:7
对采自长江下游江段的铜鱼(Coreius heterodom)肌肉营养成分进行了测定和分析。结果表明,铜鱼肌肉水分、粗蛋白质、粗脂肪和粗灰分占鲜样的比例分别为:70.03%、20.54%、6.82%和1.38%;按照氨基酸评分(Amino Acid Score,AAS)和化学评分(Chemical Score,CS)标准,铜鱼限制性氨基酸为缬氨酸和异亮氨酸,必需氨基酸指数(EAAI)为81.52;不饱和脂肪酸和ω-3多不饱和脂肪酸含量分别为63.03%和2.0%;肌肉中常、微量元素含量最高分别为钾(3135μg/g)和铁(5.46μg/g),锌铜比和锌铁比分别为8.85和0.65。 相似文献
65.
针对渤中34油田油藏孔隙度渗透率比较低、温度比较高(大于120℃)的特点,结合储层伤害原因分析,根据室内试验结果,采用多氢酸体系对渤中34油田的油井进行酸化增产作业。通过对渤中34油田5口井(均为新井,完井后基本不出液)的酸化施工,酸化成功率达到100%,酸化后各井均达到甚至超过配产要求,这表明多氢酸体系对于高温低渗砂岩地层,能够有效地解除钻完井过程中造成的污染。与常规酸液体系相比,多氢酸体系具有明显的优势且效果明显,对于类似海上油田酸化有较强的借鉴意义。 相似文献
66.
The effects of several nutritional factors on the growth and eicosapentaenoic acid (EPA) production of diatom Nitzschia laevis were studied. 4 LDM (quadrupled concentration of the nutrient salt) was the optimal concentration of nutrient salt for the
growth and EPA production of N. laevis. The growth of N. laevis was inhibited when the glucose concentration was either lower than 10 gL−1 or higher than 15 gL−1. Both sodium nitrate and urea were good nitrogen sources for the growth and EPA production, while ammonium chloride seriously
decreased the dry cell weight (DW) and the EPA content. Silicate seriously influenced the growth of N. laevis. The maximum DW of 2.34 gL−1 was obtained in the presence of 150 mgL−1 Na2SiO3·9H2O. The EPA content remained almost the same when the silicate concentration was lower than 150 mgL−1; however, higher silicate concentrations resulted in a steady decrease of EPA content. Low medium salinity (⩽29) did not
seem to influence the DW of N. laevis, and high salinity resulted in a decrease of DW. The highest EPA content (4.08%) and yield (110 mgL−1) were observed at the salinity of 36 and 29, respectively. 相似文献
67.
Study on the isotherms of the interaction between suspended particles and Cu (II) in the Huanghe River 总被引:4,自引:0,他引:4
The isotherms of the interaction between the suspended particles and Cu2+, and the effects of lysine and asparaginic acid on the isotherms in the Huanghe (Yellow) River were studied by applying the
theory and method of interfacial stepwise ion/coordination particle exchange. We obtained a new stepped river isotherm, formed
by two curves joined together with a “plateau” in the middle. The adsorption equilibrium constantsK
1 andK
2 were calculated by using the isothermal equation of surface stepwise ion exchange. Amino acid in small amount promotes exchange
adsorption of the suspended particles with Cu2+. The degree of promotive action relates to the isoelectric point of amino acid. The promotive effect of lysine is bigger
than that of asparaginic acid.
Project 29361001 supported by NSFC. 相似文献
68.
Fatty acid composition and total lipid content of 8 strains of marine diatoms (Nitzschia frustrula, Nitzschia closterium, Nitzschia incerta, Navicula pelliculosa, Phaeodactylum tricornutum, Synedra fragilaroides) were examined. The microalgae were grown under defined conditions and harvested at the late exponential phase. The major
fatty acids in most strains were 14∶0 (1.0%–6.3%), 16∶0 (13.5–26.4%), 16∶1n−7 (21.1%–46.3%) and 20∶5n−3 (6.5%–19.5%). The
polyunsaturated fatty acids 16∶2n−4, 16∶3n−4, 16∶4n−1 and 20∶4n−6 also comprised a significant proportion of the total fatty
acids in some strains. The characteristic fatty acid composition of diatoms is readily distinguishable from those of other
microalgal groups. Significant concentration of the polyunsaturated fatty acid 20∶5n−3 (eicosapentaenoic acid) was present
in each strain, with the highest proportion in B222 (19.5%).
Project supported by the Hi-Tech “863” Programs of the China Ministry of Science and Technology (863-819-02-01). 相似文献
69.
【目的】克隆马氏珠母贝(Pinctada martensii)抗酒石酸酸性磷酸酶(Tartrate resistant acid phosphatase,TRACP)基因,分析该基因在不同组织中的表达模式。【方法】用RACE技术克隆得马氏珠母贝TRACP基因(PmTRACP),用实时荧光定量PCR分析该基因在外套膜、闭壳肌、足、性腺、珍珠囊、肝胰腺和鳃中的表达。【结果与结论】PmTRACP基因长度为2 034 bp,开放式阅读框972 bp,编码323个氨基酸,5′UTR长度为27 bp,3′UTR长度为1 035 bp。预测PmTRACP分子质量约为36.39 ku,理论等电点为5.97。该基因含有一个钙调神经磷酸酶样磷酸酯酶结构域。PmTRACP与其他物种TRACP的同源性为48%~65%,与长牡蛎(Crassostrea gigas)TRACP的同源性最高,同时D32、D70、Y73、N108、H203、H212、H237、H239等8个氨基酸活性位点和N114糖基化位点在不同物种TRACP中高度保守。PmTRACP与长牡蛎TRACP的亲缘关系最近。PmTRACP在马氏珠母贝各个组织均有表达,且在肝胰腺和珍珠囊中高表达。 相似文献
70.
No studies have examined the effect of experimental warming on the microbial biomass and community composition of soil in agricultural ecosystem on the Qinghai-Tibet Plateau. Thus it is unclear whether the influences of experimental warming on microbial communities in soil are related to warming magnitude in croplands on this Plateau. This study performed warming experiment (control, low- and high-level) in a highland barley system of the Lhasa River in May 2014 to examine the correlation between the response of microbial communities in soil to warming and warming magnitude. Topsoil samples (0-10 and 10-20 cm) were collected on September 14, 2014. Experimental warming at both low and high levels significantly increased soil temperature by 1.02 ℃ and 1.59 ℃, respectively at the depth of 15 cm. Phospho lipid fatty acid (PLFA) method was used to determine the microbial community in soil. The low-level experimental warming did not significantly affect the soil’s total PLFA, fungi, bacteria, arbuscular mycorrhizal fungi (AMF), actinomycetes, gram-positive bacteria (G+), gram-negative bacteria (G-), protozoa, the ratio of fungi to bacteria (F/B ratio), and ratio of G+ to G- (G+/G- ratio) at the 0-10 and 10-20 cm depth. The low-level experimental warming also did not significantly alter the composition of microbial community in soil at the 0-10 and 10-20 cm depth. The high-level experimental warming significantly increased total PLFA by 74.4%, fungi by 78.0%, bacteria by 74.0%, AMF by 66.9%, actinomycetes by 81.4%, G+ by 67.0% and G- by 74.4% at the 0-10 cm depth rather than at 10-20 cm depth. The high-level experimental warming significantly altered microbial community composition in soil at the 0-10 cm depth rather than at 10-20 cm depth. Our findings suggest that the response of microbial communities in soil to warming varied with warming magnitudes in the highland barley system of the Lhasa River. 相似文献