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121.
玲珑西山幔源脉岩主微量元素的变化暗示了源岩很可能经历过类似俯冲带流体的交代作用,矿化流体中含有较高含量的金属矿物,具有Eu的正异常,指示了源区是深源的。脉岩中的CO2来源可能是花岗岩岩浆热液的混入,石英来源于陆壳碎屑物质部分熔融形成的S型花岗岩,硫的来源与幔源脉岩岩浆同源,或来自地幔,或来自地壳深部。  相似文献   
122.
基于多元对应分析的国家地质公园综合价值及分类   总被引:1,自引:0,他引:1  
刘佳  姚华军  高伟  冯春涛  李闵 《地质通报》2016,35(5):842-849
目前地质公园的分类难以针对具有多重价值属性的各类地质公园提出行之有效的分类管理模式。提出基于综合价值的国家地质公园分类模式,建立了国家地质公园综合价值评价指标,通过问卷调查与小组讨论获取了35个国家地质公园的量化综合价值评价指标数据,应用多元对应分析对量化数据进行统计处理,最后将35个国家地质公园分为禀赋型地质公园、生态型地质公园、成熟型地质公园、均衡型地质公园和发展型地质公园五大类,为国家地质公园分类管理提供依据。  相似文献   
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124.
A single specimen of the pelagic shrimps, Pasiphaea japonica Omori, 1976 (Pasiphaeidae) collected in the southeastern waters of Korea is described and illustrated. Although this species occurs widely in the Indo-West Pacific including the Japanese coast of the East/Japan Sea and the middle and southern parts of the East China Sea, this is the first record of the species and the genus in Korean waters. The species is distinguished from other congeners by the following combination of characteristics: non-carinate dorsal sixth abdominal somite with a terminal tooth, rudimentary pleurobranch on the eighth thoracic somite, merus of the first pereopod with more than eight spines, and almost entirely transparent white color.  相似文献   
125.
Modern and fossil benthic foraminifera were examined from nine surface sediments and two piston cores along the ~131°W transect in the equatorial Pacific Ocean. This study was conducted to clarify the biotic response of abyssal benthic foraminifera during the last 220 ka to changes in the seasonal extent of the Intertropical Convergence Zone (ITCZ). The abundance of modern benthic foraminifera was high at stations between the equator and 6°N, whereas it was low at stations north of 6°N, which is generally consistent with the latitudinal CaCO3 distribution of surface sediments. The northward increase of Epistominella exigua from the equator to ~6°N is similar to the seasonal variations in chlorophyll-a concentrations in the surface water and ITCZ position along ~131°W. This species was more common at core PC5103 (~6°N) than at core PC5101 (~2°N) after ~130 ka, when the Shannon-Wiener diversity (H’) between the two cores started to diverge. Hence, the presentday latitudinal difference in benthic foraminifera (E. exigua and species diversity) between ~2°N and ~6°N along ~131°W has been generally established since ~130 ka. According to the modern relationship between the seasonality of primary production and seasonal ITCZ variations in the northern margin of the ITCZ, the latitudinal divergence of benthic foraminiferal fauna between ~2°N and ~6°N since ~130 ka appear to have been induced by more distinct variations in the seasonal movement of ITCZ.  相似文献   
126.
从来自深海沉积物的太平洋火色杆菌(Flammeovirga pacifica)的基因组中发现了一个全长为1 875 bp的α-淀粉酶基因amy608.该基因在数据库中找不到具有同源性的序列,而所编码的Amy608蛋白与已注册蛋白的氨基酸序列相似性最高仅为56%,但具有α-淀粉酶水解活性所必需的保守基序DXEXD.进化树分析表明其属于糖苷水解酶13(GH13)家族第二亚家族.构建了p ColdΙ-amy608表达载体,在大肠杆菌中进行重组Amy608蛋白的异源表达,并采用镍离子亲和层析柱对重组蛋白进行了纯化.酶学性质分析表明,重组酶Amy608的最适作用温度为40℃,在40℃保温4 d后,仍保留70%以上的酶活,显示出良好的中温热稳定性;最适p H值为7.0,p H值范围在6~9时仍保留60%以上的酶活力,表明该酶具有较宽的p H值作用范围.Ca2+、Na+、K+对α-淀粉酶Amy608有激活作用,尤其是Ca2+可使酶活显著提高40%.薄层色谱分析结果显示该酶水解可溶性淀粉的最终产物以葡萄糖为主,表明该酶是一个糖化型淀粉水解内切酶.这些结果表明Amy608为GH13家族第二亚家族中一个新型的α-淀粉酶.  相似文献   
127.
从印度洋深海沉积物中分离出一株能够高效降解甲醛的假单胞菌(Pseudomonas sp.IOFA1),该菌株可在40 min内完全降解100 mg/cm~3的甲醛.通过阴离子交换柱层析对菌株破碎液中的粗酶液进行纯化,得到一条具有甲醛降解活性的单一蛋白条带.经MALDI-TOF/TOF质谱鉴定,该蛋白为甲醛歧化酶蛋白(FM11).序列分析表明FM11与其它物种已知醛脱氢酶的氨基酸序列最高相似性为65%;结构域分析表明FM11含有2个保守的锌结合位点和一个NAD结合位点.酶学性质分析结果显示,FM11的最适反应温度为40℃,在25~50℃范围内能够保留95%以上的酶活力,尤其是在高于70℃的高温环境下仍保有约50%的活力,表现出广泛的温度适应性.FM11具有非常广泛的最适反应pH值范围(pH值为5~9),且在pH值4和pH值10时仍分别保留50%和80%左右的酶活力,表现出广泛的pH适应性.在pH值为5~7的条件下孵育1 h后,FM11仍保有97%以上的酶活,且在pH值为7~10条件下孵育1 h后,仍保留90%以上的酶活,表现出极好的酸性和碱性稳定性.Ca~(2+)、Mg~(2+)在低浓度时(0.5 mmol/dm~3)对FM11有较明显的激活作用.这些研究为我们进一步开发Pseudomonas sp.IOFA1甲醛歧化酶在降解甲醛方面的用途奠定了基础.  相似文献   
128.
Phenotypic and genetic parameters for growth-related traits in the half-smooth tongue sole, Cynoglossus semilaevis, were estimated in 22 full-sib families produced by normal and neo-male breeding stocks. As phenotypic males with female genotypes, neo-males are harmful in C. semilaevis aquaculture because they reduce overall production. The present study evaluated the difference in the growth-related traits: total length (TL), body weight (BW) and square root of body weight (SQ_BW) at the age of 570 days between normal and neo-male offspring (neo-males used as male parents). The difference in the proportion of females between normal and neo-male offspring was also assessed. Based on the linear mixed model, restricted maximum likelihood (REML) and best linear unbiased prediction (BLUP) were used to estimate various (co)variance components and estimated breeding values (EBVs) of growth-related traits. As a result, all the mean values of the three studied traits were significantly larger in normal offspring than in neo-male offspring. Additionally, the female proportion was significantly larger in normal offspring than in neo-male offspring. Heritability was 0.128±0.066 2 for TL, 0.128±0.065 5 for BW and 0.132±0.062 9 for SQ_BW, all of which were low level heritabilities. The correlation coefficients of EBVs and phenotypic values of the target traits were 0.516 for TL, 0.524 for BW and 0.506 for SQ_BW, all of which were highly significant (P <0.01). Genetic correlations among TL, BW and SQ_BW were positive high (0.921–0.969) and higher than those of phenotype (0.711–0.748), both of which had low standard errors (0.063–0.123 for genotype, and 0.010–0.018 for phenotype). Compared with normal offspring, neo-male offspring have lower breeding values for each studied trait through EBVs comparison. Therefore, neo-male offspring should not be used as broodstock in a C. semilaevis breeding programs.  相似文献   
129.
A suite of 27 oils from the Qinjiatun–Qikeshu oilfields in the Lishu Fault Depression of the Songliao Basin was analyzed using whole oil gas chromatography. In combination with the relative distribution of C27, C28, and C29 regular steranes, detailed geochemical analyses of light hydrocarbons in oil samples revealed crude oils characterized by the dual input of lower aquatic organisms and higher terrestrial plants. Several light hydrocarbon indicators suggest that the liquid hydrocarbons have maturities equivalent to vitrinite reflectances of around 0.78%–0.93%. This is consistent with the maturity determination of steranes C29 20S/(20S + 20R) and C29 ααβ/(ααα + αββ). Crude oils derived from the two distinct oilfields likely both have source rocks deposited in a lacustrine environment based on light hydrocarbon parameters and on higher molecular weight hydrocarbon parameters. The results show that light hydrocarbon data in crude oils can provide important information for understanding the geochemical characteristics of the Qinjiatun–Qikeshu oils during geologic evolution.  相似文献   
130.
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