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31.
正The 2017 Geoscience Frontiers Annual Convention was held in Beijing,China during October 19-21,2017 hosted by China University of Geosciences,Beijing(Fig.1).This convention assembled earth scientists from seven countries,including Australia(Dr.Christopher Spencer and Dr.Stijn Glorie),Korea(Dr.S.Kwon),India(Dr.Shaji Erath),Japan(Dr.Toshiaki Tsunogae and Dr.Masaki Yoshida),Russia(Dr.Inna Safonova),UK(Dr.Nick Roberts),China,and also  相似文献   
32.
With the development and popularization of smartphones and embedded sensors, a non-professional atmospheric measurement method by using smartphones carried by the public has been proposed recently. Without extra dedicated instrument, this method has many advantages, such as low hardware cost, high spatio-temporal resolution, and wide coverage, and it can supplement the professional atmospheric measurement methods, which has broad applications in the meteorological operation, scientific research, public service, and other fields. At present, the research on the non-professional atmospheric measurement in China is limited. In order to make full use of this method, this paper briefly outlined the states of existing smartphones and embedded sensors, highlighted the measurement of precipitation, air temperature, pressure, aerosols, and radiation by smartphones. To promote the development of smartphones for atmospheric measurement, future research should focus on mechanism study, available sources exploration, data quality control, big data processing, joining and matching with operation, research and service, etc.  相似文献   
33.
The Early Cretaceous deposits are composed of important source rocks in Boli Basin. The types of the source rocks include black mudstones and coal (with carbonaceous mudstone). By the organic geochemical analysis methods, the authors discussed the organic petrological characters, abundance of organic matter, degree of maturity and the type of source rocks. The main micro-component of black mudstone is exinite or vitrinite, and the content of vitrinite is high in coal. The weathering of the outcrop is very serious. The abundance of organic matter in source rock reaches the poor to better rank. The major kerogens in mudstone are type-Ⅲ, type-Ⅱ2 and some type-Ⅱ1; the organic type of coal is type-Ⅲ. The thermal evolution of the source rocks in every structural unit is very different, from low-maturity to over-maturity. The depositional environment is reductive, which is good for the preservation of organic matter. The organic matter in source rocks is mainly from aquatic organisms and terrigenous input.  相似文献   
34.
高超利 《地质与勘探》2024,60(2):414-424
鄂尔多斯盆地中部洛河油田长61低渗透油层由于含油饱和度变化大、油层非均质强,再加淡水钻井液侵入,造成油层电阻率径向分布不均且变化大。通过双感应-八侧向测井与阵列感应测井响应特征对比分析,认为水层的径向电阻率均为增阻侵入,油层、油水同层的径向电阻率普遍具有减阻侵入、低阻环带、高阻环带特征或相关趋势。其中,减阻侵入有助于识别高含油饱和度、高电阻率油层和油水同层,低阻环带和高阻环带有助于识别低电阻率油水同层。另外,部分油水同层的双感应-八侧向测井径向电阻率组合具有“增阻侵入”且深感应电阻率低的特征,推测可能是受双感应-八侧向测井探测范围限制,为低阻环带靠近井眼附近遭受淡水钻井液侵入影响的结果,深感应测井反映的是侵入带电阻率而不是油水同层的电阻率,容易被误解释为水层。因此,对于双感应-八侧向测井中具有“增阻侵入”特征且深感应电阻低值的储层,其流体性质有水层、油水同层这两种可能性,需要结合深探测测井资料或油藏地质特征进一步分析,以提高油层、水层的识别率。  相似文献   
35.
Making use of quasar spectra from LAMOST,in the spectral data around the Mg Ⅱ emission lines,research described in this paper has detected 217 Mg Ⅱ narrow absorption lines(NALs) with W_r ~(λ2796)≥3σ_w and W_r~(λ2803)≥ 2σ_w in a redshift range of 0.4554≤z_(abs)≤2.1110.For quasars observed by both LAMOST and SDSS,we find that 135 Mg Ⅱ NALs were obviously observed in the LAMOST spectra,347 Mg Ⅱ NALs were were apparent in the SDSS spectra,and 132 Mg Ⅱ NALs were clearly present in both the SDSS and LAMOST spectra.The missed Mg Ⅱ NALs are likely ascribed to low signal-to-noise ratios of corresponding spectra.Among the Mg 11 NALs obviously observed in SDSS or LAMOST spectra,eight Mg 11 NALs were significantly changed with |ΔW_r ~(λ2796)|≥3σ_w in time intervals of ΔMJD/(1+z_(em))=359-2819 d.  相似文献   
36.
摘要:目的 探讨菌株Salinivibrio sp.YH4分泌的丝氨酸蛋白酶EYHS的耐盐性及结构特征。方法 明胶底物酶谱法分析EYHS的耐盐性。应用生物信息学手段对EYHS及6种耐盐的S8家族丝氨酸蛋白酶结构特征进行分析。结果 EYHS在4 mol/L的NaCl溶液中仍具有活性,属于耐盐蛋白酶。EYHS及6种S8家族丝氨酸蛋白酶分子表面的loop区等无规则卷曲所占比例较高,α-螺旋与β-片层则主要位于酶分子内部。EYHS分子表面酸性氨基酸含量较高,且具有弱疏水内核。多序列比对发现蛋白酶的催化三联体两侧存在高度保守的基序和保守的极性氨基酸及芳香族氨基酸,并存在多个保守的Gly与Ala。同源模建和表面电荷分布显示,α螺旋和β片层围成了蛋白酶的催化腔,EYHS活性中心包含由Asp32、His65与Ser215组成的催化三联体,且催化位点区域表面静电势为负。结论 上述结构特征可能有助于耐盐丝氨酸蛋白酶EYHS在高盐环境下维持其稳定性和适度柔性,并有助于其催化功能的发挥,为深入研究耐盐丝氨酸蛋白酶的高盐环境适应性提供了一定的理论依据。  相似文献   
37.
Qi  Miaomiao  Yao  Xiaojun  Li  Xiaofeng  Duan  Hongyu  Gao  Yongpeng  Liu  Juan 《地理学报(英文版)》2019,29(1):115-130
Journal of Geographical Sciences - Lake ice phenology is considered a sensitive indicator of regional climate change. We utilized time series information of this kind extracted from a series of...  相似文献   
38.
39.
2013年青岛输油管道爆炸,大量石油污染了附近海岸。课题组采集了污染的沉积物样品,以原油为唯一碳源和能源,富集了四个石油降解菌群。生物多样性和群落分析表明,Luteibacter、Parvibaculum 和属于食烷菌科的一个属是降解菌群的主要优势菌,都属于变形菌门。从石油降解菌群中分离筛选,获得了9株具有不同16S rRNA基因序列的降解菌,分别属于8个属。重量法测定降解菌的石油降解率,其中5株的石油降解率大于30%。GC-MS分析结果表明,石油降解菌多倾向于降解烷烃,对多环芳烃的降解能力较差,其中5株细菌的烷烃降解率较大,仅1株菌D2对多环芳烃的降解率较大,其降解率在34.9%到77.5%。通过对高通量数据的分析,表明食烷菌属是菌群A和菌群E的主要降解菌群,其中筛选获得的菌株E4可能是菌群E的一株优势降解菌。本研究所筛选菌株证明了其石油降解潜力,为油污染海滩生物修复提供了菌株资源。  相似文献   
40.
Shi  Ce  Gao  Xiaolong  Liu  Ying  Wang  Chunlin 《中国海洋湖沼学报》2019,37(1):344-349

Self-feeding device is extensively used in aquaculture farms, but for salmonids the individual feeding behavior has seldom been continuously observed. In this article, the individual self-feeding behavior of 10 rainbow trout was continuously monitored with a PIT tag record for 50 days with three replicates. The fish fell into three categories according to their feeding behavior, i.e. high triggering fish (trigger behavior more than 25% of the group, HT), low triggering fish (1%–25%, LT) and zero triggering fish (less than 1%). The results showed that in a group of 10 individual 1–2 HT fish accounted for most of the self-feeding behavior (78.19%–89.14%), which was far more than they could consume. The trigger frequency of the fish was significantly correlated with the initial body weight (P <0.01), however, no significant difference in growth rate among the HT, LT, and ZT fish was observed (P >0.05). Cosinor analysis showed that the two HT fish in the same group had similar acrophase. Though some of the HT fish could be active for 50 d, there were also HT fish decreased triggering behavior around 40 d and the high trigger status was then replaced by other fish, which was first discovered in salimonds. Interestingly, the growth of the group was not affected by the alternation triggering fish. These results provide evidence that in the self-feeding system the HT fish didn’t gain much advantage by their frequent self-feeding behavior, and high trigger status of the HT fish is not only an individual character but also driven by the demand of the group. In the self-feeding system, the critical individual should be closely monitored.

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