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1.
分光光度法测定用于废氧化铝载体铂催化剂中铂含量。铂被还原成铂黑从杂质中分离出,用王水溶解形成六氯铂酸盐酸溶液,加入氯化亚锡形成橙黄色络合物溶液在403nm进行测定。对该方法的回收率,钼存在对测定的影响进行了研究,方法回收率98~102%,在10-6数量级,即使钼浓度与铂浓度相等并不影响铂的测定  相似文献   

2.
在采用回收法治理锯条厂氰化物污水中,通过改造生产工艺,减少污水量,提高氰化物浓度及污水经除油后减压蒸馏,可回收50%~90%的氰化铂,其他盐分也可全部回收,从污水中蒸出的蒸馏水能在系统内循环使用。  相似文献   

3.
福建近海主要经济渔业生物营养级和有机碳含量研究   总被引:2,自引:0,他引:2  
卢振彬  黄美珍 《台湾海峡》2004,23(2):153-158
本文研究了福建近海52种鱼类、6种虾类、4种蟹类、1种虾蛄和4种头足类的食性和营养级及其有机碳含量。结果表明:营养级以鱼类最高,为2.1~3.7级,平均2.65级;头足类为2.04~2.88级,平均2.60级;蟹类2.38~2.73级,平均2.58级;虾类最低,为1.64~2.21级,平均1.96级.干样有机碳含量百分率也以鱼类最高,为33.0%~76.2%(m/m),平均46.25%(m/m);头足类为27.80%~46.16%(m/m),平均40.24%(m/m);虾类为30.60%~38.40%(m/m),平均34.90%(m/m);蟹类最低,为25.00%~30.78%(m/m),平均28.24%(m/m),鲜样有机碳含量百分率还是以鱼类最高,为4.80%~29.55%(m/m),平均13.75%(m/m);蟹类为8.90%~12.68%(m/m),平均10.74%(m/m);虾类为6.97%~11.53%(m/m),平均9.55%(m/m);头足类最低仅为7.38%~8.52%(m/m),平均7.95%(m/m),干样有机碳含量百分率和鲜样有机碳含量百分率与营养级均成正相关,但前者的相关性高于后者。  相似文献   

4.
紫菜胶与紫菜琼胶   总被引:2,自引:0,他引:2  
史煣  史升耀 《海洋科学》1994,18(1):48-52
研究了坛紫菜所含多糖的年率、性质和组成。用水直接提取的多糖产率为5.45~6.89%,无凝固性,含SO412.73~14.08%,含3,6-AG9.98~12.12%。经碱处理后提取的多糖产率为4.9~9.5%,最高的达19.1%,它能形成很好的凝胶,其凝胶强度达750~1100g/cm^2,含SO40.20~0.75%,含3,6-AG40.28~43.04%,它的红外光谱和^13C-NMR波谱与  相似文献   

5.
根据日立835—50型氨基酸自动分析仪生理体液分析法,以及同型胱氨酸的生理特性,建立测定同型胱氨酸的150min短程序法。经过精密度和准确度试验,重视性好,变异系数小。当同型胱氨酸浓度为4×10-5mol/L时,峰位置和峰面积的变异系数(CV值)分别为0.20%和1.98%(n=10),明显低于规定技术指标(1%和2.5%)。对1、2、4(×10-4mol/L)浓度的同型胱氨酸加标回收试验,回收率为叶.33~106.67%(n=9)。本法与原法同时测定大鼠及人体血浆的同型胱氨酸的含量结果基本一致。表明本方法准确、可靠、快速、简便,适用于高脂血症、动脉粥样硬化以及血栓等血浆中同型胱氨酸的测定。本方法样品处理采用任其与空气接触,使血浆中同半型胱氨酸氧化为同型胱氨酸,测定其总同型胱氨酸含量。  相似文献   

6.
南海黄鲷性腺发育的初步研究   总被引:1,自引:0,他引:1  
本文采用常规的生物学调查方法并取黄鲷性腺做石蜡切片,用显微镜观察黄鲷的性腺发育,进行组织学研究.其结果表明,南海黄鲷精巢可分成6期,精巢5期的成熟度指数为1.62%~2.71%,平均值为1.99%.雌性生殖细胞可见5个时相,卵巢发育也相应分成6期,卵巢5期时的成熟度指数为8.90%~13.90%,平均值为9.45%.南海黄鲷的繁殖期在11月至翌年的4月,繁殖高峰在12月至3月,黄鲷的产卵类型属于在同一繁殖季节中多次产卵类型.本文还对黄鲷的雌雄同体现象、繁殖力、繁殖时间进行了讨论.  相似文献   

7.
目的:观察双乌散寒通络方外用对奥沙利铂所致周围神经不良反应的防治效果。方法:将40 例使用奥沙利铂化疗的胃癌、结直肠癌患者随机分为治疗组和对照组,每组各20 例。治疗组在化疗时采用双乌散寒通络方浸泡手足,对照组则采用温水浸泡手足。治疗14 d后观察2组患者的中医证候疗效,周围神经不良反应分级情况,周围神经不良反应程度[化疗药物周围神经毒性生活质量问卷20(EORTC QLQ-CIPN 20)量表评分]以及其他不良反应(骨髓抑制、消化道反应、肝肾功能损伤等)。结果:第1个疗程后,2组中医证候疗效总有效率分别为90.00%(18/20)、60.00%(12/20);第2个疗程后,2组总有效率分别为85.00%(17/20)、50.00%(10/20),组间比较,差异均有统计学意义(P<0.05)。第2个疗程治疗后,2组2级、3级周围感觉性和运动性神经病变发生率比较,差异均有统计学意义(P<0.05或P<0.01)。第1、2个疗程后,2组EORTC QLQ-CIPN 20量表评分治疗前后组内比较及治疗后组间比较,差异均有统计学意义(P<0.05或P<0.01)。2组其他不良反应有骨髓抑制(白细胞减少、血小板减少、贫血),恶心,食欲减退,乏力,发热等,均为1~2级。结论:双乌散寒通络方能有效防治奥沙利铂引起的周围感觉性及运动性神经病变,且无明显不良反应。  相似文献   

8.
以红树植物白骨壤(Avicennia marina)基因组DNA为模板,根据超氧化物歧化酶基因保守序列设计特异引物进行PCR扩增,得到特异基因片段。回收该基因片段,与pMD18-T载体连接,并转化到感受态大肠杆菌ER2566细胞,获得铜锌超氧化物歧化酶基因片段的克隆。序列分析表明白骨壤铜锌超氧化物歧化酶基因片段含4个外显子和3个内含子,编码78个氨基酸,与水稻、玉米、红薯和白杨相应氨基酸序列的同源性分别为83.3%,84.6%,84.6%和87.2%。  相似文献   

9.
杂色鲍与皱纹盘鲍!盘鲍杂交的初步研究   总被引:27,自引:2,他引:27  
于1998~1999年在福建厦门和东山两地养殖场,对我国主要养殖鲍即杂色鲍与皱纹盘鲍、盘鲍进行杂交试验。结果表明,皱♂×杂♀的受精率为3.5%~15.0%,平均7.6%。皱♀×杂♂的受精率为1.5%~4.0%,平均2.8%。杂交成功的受精卵的胚胎和幼体发育均正常。杂色鲍×盘鲍杂交组合的受精率明显高于杂色鲍×皱纹盘鲍,无论哪个组合杂色鲍作为雌性亲本的杂交受精率均比反交大大提高。  相似文献   

10.
郑乐云 《台湾海峡》2003,22(2):187-191
本文报道了在海水池搪进行红鳍笛鲷人工育苗的实验结果.实验水温为26~32℃,盐度为25~31,经过33~35d的培育,3口池塘鱼的苗平均全长分别为35.3、32.3、28.5mm,成活率分别为16.7%、18.1%、7.8%.本文还对仔鱼的放养密度、生长状况、饵料系列以及池塘中主要生物饵料密度变化作了较为详细的阐述。  相似文献   

11.
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   

12.
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   

13.
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   

14.
15.
Oedometer tests have been carried out on 70 undisturbed surficial clays (at approximately 250 mm below the mudline), mostly collected by free-fall corers from sites widely scattered throughout the deep-sea North Atlantic. Acoustic measurements were also made, initially on contiguous samples and ultimately on the same sample using a geophysically instrumented oedometer which also collected electrical resistivity data. Apart from those quiescent areas below the carbonate compensation depth, such as north of the West Indies where very fine clays exist, most of the samples are silty clays whose geotechnical-geophysical properties are dependent on the type of clay minerals present (and their ability to take in moisture), the sand-size fraction, and the quantity of carbonate present. Thus the pure clays have high compressibilities which decrease on the addition of coarse particles, while the converse is true for the acoustic parameters, these increasing with the sand fraction. Using the notion of the intrinsic compression line for all samples, and comparison to it of the measured compression curves, it is clear that, contrary to some previously held ideas, most deep-sea clays are normally consolidated; the addition of carbonate has the effect of creating an open, stronger sediment skeleton. Interestingly, where information is available, the variation with depth of a sample's acoustic velocity follows the void ratio pressure relationship of the compression curve. This allows the construction of an in-situ sediment compression curve using the in-situ geophysical observations.  相似文献   

16.
17.
A set of 27 marine planktonic bacteria isolated from the polar regions was characterized by 16S rDNA sequencing and physiological and biochemical testing. More than half of these bacteria were positive for caseinase, gelatinase and 13-glucosidase, and could utilize glucose, maltose or malic acid as carbon source for cell growth. Twelve isolates expressed nitrate reduction activities. Except for one antarctic isolate BSwlO175 belonging to Actinobacteria phylum, these isolates were classified as γ-Proteobacteria, suggesting that γ-Proteobacteria dominated in cultivable marine bacterioplankton at both poles. Genus Pseudoalteromonas was the predominant group in the Chukchi Sea and the Bering Sea, and genus ShewaneUa dominated in cultivable bacterioplankton in the Prydz Bay. With sequence similarities above 97%, genus Psychrobacter was found at both poles. These 27 isolates were psychrotolerant, and significant 16S rDNA sequence similarities were found not only between arctic and antarctic marine bacteria ( 〉 99% ), but also between polar marine bacteria and bacteria from other aquatic environments ( ≥ 98.8% ), including temperate ocean, deep sea, pond and lake, suggesting that in the polar oceans less temperature-sensitive bacteria may be cosmopolitan and have a bipolar, even global, distribution at the species level.  相似文献   

18.
19.
《海洋学报(英文版)》2014,(8):F0003-F0003
<正>Acta Oceanologica Sinica(AOS)is a comprehensive academic journal edited by the Editorial Committee of Acta Oceanologica Sinica and is designed to provide a forum for important research papers of the marine scientific community which reflect the information on a worldwide basis.The journal publishes scholarly papers on marine science and technology,including physics,chemistry,biology,  相似文献   

20.
This article presents a methodology developed to evaluate the instability of submarine slopes that extend over a large area. Special attention was paid to (1) the complex geometry (bathymetry) and the expanse of the slope, (2) the heterogeneity of the sediment, and (3) the distribution of the pore pressure. The safety factor was considered as a spatially varying quantity. The General Formulation (GLE, Fredlund and Krahn 1977), which fully satisfies equilibrium conditions, was used for evaluating the stability of the marine slope. The submarine slope failure, which occurred on 16 October 1979 during the construction of the new Nice airport, was studied in order to test the developed model. Geotechnical parameters were taken from experimental tests carried out by IFREMER on 19 cores extracted at different depths (from 27 m to 1300 m) (Cochonat, Bourillet, and Savoye, 1993; Mulder et al., 1994). Many scenarios were proposed in order to explain the cause of the Nice slope failure (Habib, 1994). In this article, two of those scenarios were tested. Simulation results are presented and discussed.  相似文献   

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