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1.
本文研究了Ｄ_００１大孔阳离子强酸树脂从Ｈ_２ＳＯ_４－ＣＳ（ＮＨ_２）_２溶液中，富集及分离Ａｕ（Ｉ）、Ａｇ（Ｉ）的性能。表明在ｐＨ＝２．０左右，树脂对Ａｕ（Ｔｕ）￣＋_２、Ａｇ（Ｔｕ）￣＋_２（Ｔｕ＝硫脲）有良好的吸附性能，Ａｕ和Ａｇ的吸附容量分别为６１．１８ｍｇ／ｇ－Ｒｅｓｉｎ和９９．１１ｍｇ／ｇ—Ｒｅｓｉｎ。负载柱上的Ａｕ、Ａｇ可分别用ＮａＣＮ—ＮａＯＨ和Ｈ_３ＢＯ_３－ＮａＯＨ－Ｎａ_２Ｓ_２Ｏ_３定量洗脱。可进行一定程度的Ａｕ、Ａｇ分离。 相似文献
2.
《中国海洋湖沼学报》2021,(5)
The genus Munidopsis has high biodiversity in seamount habitats.In this study,two new Munidopsis species,Munidopsis ahyongi sp.nov.and Munidopsis carolinensis sp.nov.from the Caroline Ridge in the tropical western Pacific Ocean were described.M.ahyongi sp.nov.is very similar to a group of species in the M.serricornis complex,but can be readily distinguished from the related species in having the oblique posterior orbital margins,2 spines on the lateral carapace margin,and a relatively longer rostral median spine.M.carolinensis sp.nov.is different from two related species primarily in having oblique frontal margins,blunt outer orbital angles,straight lateral margins of the rostrum,scale-like rugae on sternites 5-7,and less spinose pereopod 1(chelipeds,P1) merus and carpus.Aside from the morphological comparisons,DNA barcode analysis and phylogenetic analysis based on the cytochrome c oxidase subunit I gene(COI) were employed for the identification of these new species. 相似文献
3.
利用1999~2009年的IGS电离层电子浓度总含量(TEC)数据,分析全球TEC白天值Idc和夜间值Inc的半年变化、季节变化特性,并研究二者跟太阳、地磁活动的关系。结果表明,Idc最大值出现在春秋分季节是一个非常普遍的现象。除了北半球近极地地区和南半球的南美洲地区外,Idc的半年变化特性都很明显;Inc只在低纬度地区具有半年变化特性,并且Idc和Inc半年变化特性随太阳活动变化而变化,在太阳活动高年,全球85%以上地区Idc最大值出现在春秋分季节;Idc和Inc的季节变化特性随经纬度变化,并且在太阳活动高年季节变化明显;在一个太阳活动周期上Idc、Inc与太阳活动P指数日均值的相关性较强,相关系数达到0.9,但与地磁活动Dst、Kp、Ap指数日均值的相关性较弱,相关系数小于0.4。本文进一步展示了太阳天顶角控制的电离层光化学产生率对电离层TEC整体变化特征起主要作用。 相似文献
4.
????1999~2009???IGS????????????????(TEC)????????????TEC???????I????dc????????????I????nc?????????仯??????仯????????о????????????????????????????????I????dc???????????????????????????????????????????????????????????????????????????I????dc?????????仯??????????????I????nc????????γ????????а???仯??????????I????dc???????I????nc????????仯????????????仯???仯????????????????85%?????????I????dc????????????????????????I????dc???????I????nc?????????仯?????澭γ??仯???????????????????仯??????????????????????I????dc????????I????nc?????????????P????????????????????????????0.9???????????D????st????K??p??A??p???????????????????????????С??0.4??????????????????????????????????????????TEC????仯????????????á? 相似文献
5.
Two Large-insert genomic bacterial artificial chromosome （BAC） libraries of Zhikong scallop Chlamys farreri were constructed to promote our genetic and genomic research. High-quality megabase-sized DNA was isolated from the adductor muscle of the scallop and partially digested by BamH I and Mbo I, respectively. The BamH I library consisted of 53 760 clones while the Mbo I library consisted of 7 680clones. Approximately 96 % of the clones in BamH I library contained nuclear DNA inserts in average size of 100 kb, providing a coverage of 5.3 haploid genome equivalents. Similarly, the Mbo I library with an average insert of 145 kb and no insert-empty clones, thus providing a genome coverage of 1.1 haploid genome equivalents. 相似文献
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1 ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｅａｆｔｅｒｎｏｏｎｒｅｇｉｏｎ (ａｐｐｒｏｘｉｍａｔｅｌｙ 1 4 0 0ｔｏ 1 60 0ＭＬＴ)ｈａｓａｓｐｅｃｉａｌｓｉｇｎｉｆｉｃａｎｃｅｆｏｒａｖａｒｉｅｔｙｏｆｍａｇｎｅｔｏｓｐｈｅｒｉｃｐｈｅｎｏｍｅｎａ.Ｉｔｓｐｒｏｘｉｍｉｔｙｔｏｍａｇｎｅｔｉｃｎｏｏｎｓｕｇｇｅｓｔｓｔｈａｔｔｈｅａｕｒｏｒａｌｐｈｅｎｏｍｅｎａｏｂｓｅｒｖｅｄｍａｙｂｅｒｅｌａｔｅｄｔｏｄａｙｓｉｄｅｍａｇｎｅｔｏｓｐｈｅｒｉｃｐｒｏｃｅｓｓｅｓ ,ａｎｄｉｎｄｅｅｄａｖａｒｉｅｔｙｏｆｓｔｕ… 相似文献
7.
在地理栅格并行计算处理中,数据I/O 已成为制约计算性能的主要瓶颈之一。本文针对该问题,首先分析广泛应用于GIS 栅格数据存储的GeoTIFF 格式,重点研究数据的2 种存储模式(即条带存储与块状存储),并根据这2 种存储方式,分别构建了栅格数据从逻辑结构向物理存储结构的映射模型。然后,针对地理空间并行计算的需要,提出了栅格数据的并行读写框架,并利用MPI 并行I/O 技术的文件视图方法,实现了GeoTIFF 数据并行I/O库(pGTIOL)。结果表明,对比开源栅格空间数据转换库(GDAL)的主从I/O 模式,本文提出的pGTIOL 准确读写数据,具有更高的性能。该库隐藏了底层并行I/O 的细节,提供简单易用的并行读写GeoTIFF 栅格数据的接口,支持多数据类型和多种空间分割,实现了对条带存储与块状存储数据的异步并行读写,从而满足动态负载均衡的需求。 相似文献
8.
硝酸益康唑微囊化技术研究 总被引：3，自引：0，他引：3
以明胶与阿拉伯胶配比为囊材，Span60为乳化剂，戊二醛为交联剂，采用复凝聚法制备了硝酸益康唑微胶囊．并研究了制备工艺条件对微胶囊形态、粒度、药物包封率及释放特性的影响。结果表明，随药物与囊材配比增大．形成的微胶囊数目越多、粒径越小，包封率降低，释放速度增大；戊二醛的用量对微胶囊膜的机械强度、微胶囊形状和粒度及分散性有显著影响。 相似文献
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10.
琼中黎母山-湾岭地区位于海南岛中部,调查发现该地区土壤同时具有富硒、富碘的特征。以研究区表层（0~20 cm）、中层（80~100 cm）、深层（180~200 cm）土壤样品分析结果为基础,探讨了土壤硒、碘的分布特征及其影响因素。结果显示,表层土壤中Se、I质量分数具有高正相关性,并与高程为正相关关系,结合已有研究成果,推断在研究区范围内降雨作用是研究区表层土壤Se、I质量分数空间分布格局的关键影响因素。通过分析表层、中层、深层土壤Se、I质量分数与土壤pH值、总有机碳（TOC）、Al2O3、Fe2O3质量分数的相关关系和变化规律,总结了研究区Se、I在土壤垂向剖面上的赋存、迁移规律。这些结果可为当地优质土地资源的高效利用提供科学依据,也可为土壤Se来源、迁移研究提供新的证据。 相似文献
11.
北斗地基增强系统是推广高精度“北斗+”应用的重要基础设施。本文首次研究千寻位置、六分科技及中国移动3家覆盖全国的北斗地基增强系统的定位服务性能,通过对2021-07-21~22采集的2次8~9 h观测数据进行分析,得到以下结论： 1） 千寻位置和中国移动的官方推荐挂载点支持BDS-2三频信号和BDS-3双频信号（B1I、B3I）,六分科技支持BDS-2和BDS-3双频信号（B1I、B3I）; 2） 3家北斗地基增强系统都能提供100%的北斗数据完整率; 3） 静态基线结果表明,3家北斗地基增强系统虚拟基站组成的闭合环相对误差均小于2×10-6; 4） 单历元RTK解算结果表明,3家北斗地基增强系统均能够提供水平向优于3 mm、垂直向优于9 mm的内符合精度,但不同北斗地基增强系统之间存在cm~dm级的定位结果偏差,因此不建议在RTK作业时使用不同的北斗地基增强系统。 相似文献
12.
XU Jiachao GAO Xin ZHANG Zhaohui LI Zhaojie HUO Lihua and XUE Changhu Department of Food Science Engineering Ocean University of China Qingdao P. R. China 《中国海洋大学学报(英文版)》2006,(2)
Fucoidan is such a polysaccharide that its hydroxies are easy to combine with lanthanons ion (CeIV) to form complex. This work obtained the complexes of three fucoidan oligosaccharides with different molecular weights F1(>5000), F2 (1000-5000) and F3(<1000) by hydrolyzing Oligosaccharide collagen with sulfuric acid. It is found that the fucoidan oligosaccharide F3 can form complex with more CeIV than F1 and F2. Hydrolyzing collagen with the complex was carried out to produce amino acid and peptides. All the three fucoidan oligosaccharide complexes with CeIV( F1, F2, F3) can catalyze by the artificial hydrolytic enzyme, and the activity of the complex of F3 is the highest. 相似文献
13.
Fucoidan is such a polysaccharide that its hydroxies are easy to combine with lanthanons ion (CeⅣ) to form complex. This work obtained the complexes of three fucoidan oligosaccharides with different molecular weights F1( ＞5 000), F2(1 000-5 000) and F3( ＜ 1 000) by hydrolyzing Oligosaccharide collagen with sulfuric acid. It is found that the fucoidan oligosaccharide F3 can form complex with more CeⅣ than F1 and F2. Hydrolyzing collagen with the complex was carried out to produce amino acid and peptides. All the three fucoidan oligosaccharide complexes with CeⅣ( F1, F2, F3) can catalyze by the artificial hydrolytic enzyme, and the activity of the complex of F3 is the highest. 相似文献
14.
Analyzing raw material's structure and performance of bentonite from Panzhihua in Sichuan, the authors think that it is adequate for agglomerant of iron smelting. According to its composition and property we have researched the purification and modification of I/S bentonite under conditions of different dispersants and sodium agent. XRD test result reveals that the essential minerals of Panzhihua bentonite are I/S mixed-layer ones, and FTIR analysis shows that when adding 1 5% sodium pyrophosphate to the bentonite slurry during purification, the composition of quartz in bentonite decreases to less than 4% and I/S is more than 90%. The optimized modification technic conditions are Na2CO3 (4%) and CMC-Na (3%) as modified agents, the clay and water are 10 vs. 1, and the temperature is 75℃. It is 40 min for stirring time and reacting time is 4 h. Under the conditions we can get the modified I/S bentonite with colloid index more than 500 ml/15 g. 相似文献
15.
《中国海洋湖沼学报》2017,(3)
Silver carp is one of the most important planktivorous fish in Chinese aquaculture and plays a significant role controlling cyanobacterial blooms. A balanced gut microbiota is crucial for growth and health of the host because of its important roles in immune defense, digestion of complex carbohydrates, and production of enterocytes. In our study, the dominant bacterial and cellulolytic bacterial( Clostridium I, Clostridium III, Clostridium XIVab, and Fibrobacter) communities in the contents and mucus of the silver carp gut(foregut, midgut, and hindgut) were analyzed by denaturing gradient gel electrophoresis and quantitative polymerase chain reaction(q PCR) analyses. The results revealed that the dominant and cellulolytic bacterial communities were significantly different among gut regions as well as in contents and mucus. Bacterial diversity and richness in contents and mucus increased along the gut and were higher in contents than those in local mucus. A sequence analysis of gut samples exhibited the conservative phylotypes of Proteobacteria, Actinobacteria, and Firmicutes. The gut of silver carp harbored an abundance of cellulolytic bacteria, particularly Clostridium XIV ab. The foregut segment had the highest proportions of the four cellulolytic bacteria, followed by the midgut and hindgut. However, the proportions of cellulolytic species in the silver carp gut was much lower than those in the terrestrial vertebrate gastrointestinal tract. We conclude that gut bacteria could help silver carp obtain energy from cyanobacteria, which may be why silver carp can maintain high growth rates during cyanobacterial blooms. 相似文献
16.
Yingchun Lv Rong Zheng Tao Zuo Yuming Wang Zhaojie Li Yong Xue Changhu Xue Qingjuan Tang 《中国海洋大学学报(英文版)》2014,13(5):825-829
Sea cucumbers are traditional marine food and Chinese medicine in Asia. The rapid expansion of sea cucumber market has resulted in various problems, such as commercial fraud and mislabeling. Conventionally, sea cucumber species could be distinguished by their morphological and anatomical characteristics; however, their identification becomes difficult when they are processed. The aim of this study was to develop a new convenient method of identifying and distinguishing sea cucumber species. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis of mitochondrial cytochrome oxidase I gene (COI) was used to identifing five sea cucumber species (Apostichopus japonicus, Cucumaria frondosa, Thelenota ananas, Parastichopus californicus and Actinopyga lecanora). A 692 bp fragment of COI was searched for BamHI, KpnI, PstI, XbaI and Eco31I restriction sites with DNAMAN 6.0, which were then used to PCR-RFLP analysis. These five sea cucumber species can be discriminated from mixed sea cucumbers. The developed PCR-RFLP assay will facilitate the identification of sea cucumbers, making their source tracing and quality controlling feasible. 相似文献
17.
This paper deals with the infrared spectra of " amino acid- clay , calcium carbonate and y-AlOOH" and " Cu (II )-clay-amino acid" model systems, and shows that the model of the ternary surface complex is M-OHLCu (L = amino acid) for marine solid particle-Cu (II)-amino acid. Study of the formation mechanism of the ternary surface complex shows that the specific surface area , and especially the intrinsic acidity constant, determine whether the ternary surface complex is easily formed, and that factor, FTSC,quantifies the relationship between the promoting effect of organics on Mt-marine solid particle ion exchange and the intrinsic acidity constant and specific surface area. 相似文献
18.
复杂的面状空间实体如海洋涡旋、环流和降雨过程在运动过程中会产生更复杂的轨迹,即具有分支结构的复杂轨迹。为了挖掘这类复杂轨迹的运动模式特征,本文从复杂轨迹的拓扑结构和空间特征出发,创新性地提出复杂轨迹的空间-拓扑结构相似性度量算法（Spatial-Topological Similarity Measurement, STSM）,该算法是基于图同构算法VF2改进的。首先STSM算法将复杂轨迹用带有节点和边的图结构表达,并将空间信息融入图结构的节点属性中,通过匹配复杂轨迹之间所有最大公共子结构,找到匹配结构中节点之间一一对应的关系,利用加权的欧式距离计算复杂轨迹匹配结构中点对之间的空间距离。然后,基于STSM相似性算法进行层次聚类分析,旨在发现复杂轨迹之间相似的拓扑结构在空间上的聚集模式。最后,利用1993-2016年长时间序列的中国南海冷涡复杂轨迹验证方法的有效性,并对比分析复杂轨迹拓扑结构相似性算法CSM。结果表明：单纯用拓扑结构相似性算法CSM进行聚类分析,不能充分挖掘空间的聚集模式,因为不同空间位置也存在拓扑结构相似的轨迹。而本文提出的STSM算法将南海冷涡复杂轨迹分为5类,第一类分布在南海北部、第二类分布在南海中部、其他三类交错在南海南部。这种聚集模式在一定程度上反映了冷涡的生成和演化过程在南海北部、中部、南部的差异性,同时也表明了冷涡移动在南海南部存在更为复杂的异质性。因此,本文提出的方法可以有效地从复杂轨迹数据中发现其演化过程的潜在聚集模式,为认识这类复杂动态现象的时空演化特征提供了一种新的方法。 相似文献
19.
WTO《补贴与反补贴措施协定》附件一(K)款二项是一个较为复杂和重要的条款,涉及的内容较多,如“官方出口信贷的国际承诺”、“后续承诺”、“出口信贷做法”、“符合”等措辞的解释与适用问题。在巴西诉加拿大影响民用飞机出口措施案中,专家组及上诉机构的报告对于澄清上述问题起了重要的作用。 相似文献
20.
鲁西太古代徂徕山杂岩体主要由片麻状花岗岩和钾长花岗岩构成,此外尚发育少量小规模的中粗粒、细粒闪长岩。本文着重讨论花岗质岩石的成因。徂徕山杂岩体岩石地球化学研究表明,片麻状花岗岩为深源(下地壳)花岗质岩浆侵位结晶的产物;钾长花岗岩是片麻状花岗岩在区域变质作用过程中部分熔融形成的,两者具有密切的成因联系。 相似文献