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1.
为深入了解西北太平洋表层沉积物地球化学特征及物质来源,对大洋40航次在西北太平洋马尔库斯-威克海山区采集的表层沉积物进行了全岩地球化学和黏土矿物测试分析。结果表明,研究区表层沉积物稀土元素(REE)平均质量分数为302.87×10-6,北美页岩标准化稀土配分模式与黄土相似,并具Ce轻微负异常和Eu无异常特征。稀土配分模式、判别函数(discriminant functions,DF)、M/I(蒙脱石/伊利石)及涂片鉴定等结果指示沉积物物源具有多源性,主要为陆源风尘物质,并受海洋自生物质的强烈影响,海山玄武岩及其蚀变产物和硅质生物也有一定的贡献。研究区沉积物稀土特征既不同于边缘海沉积物,也有别于远洋沉积物,而与弧后盆地沉积物类似。结合1/δCe-LREE/HREE和LREE/HREE-Y/Ho判别图解结果,研究区沉积物物源结构属性应介于边缘海沉积物与远洋沉积物之间,为洋陆过渡区沉积。 相似文献
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Liu Wei Li Kehong Deng Hao Wang Jing Zhao Peng Liao Wei Zhuo Liangang Wei Hongyuan Yang Xia Chen Yue 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(2):747-754
Journal of Radioanalytical and Nuclear Chemistry - There is an urgent need to develop more specific targeted therapies for lung cancer treatment due to the its low survival rate. EGFR is a... 相似文献
3.
The Aerobic Oxidation and C=C Bond Cleavage of Styrenes Catalyzed by Cerium(IV) Ammonium Nitrate (CAN) 下载免费PDF全文
Lei Yu Yaping Huang Zengbing Bai Bingchun Zhu Kehong Ding Tian Chen Yuanhua Ding Yuguang Wang 《中国化学会会志》2015,62(6):479-482
The CAN‐catalyzed aerobic oxidation severed the C=C bond selectively through the single electron transfer mechanism, giving a green method to decompose olefins. Compared with the literature reported examples, this method required simple catalyst, cheap, abundant and clean oxidant and was very safe to operate due to the mild conditions. 相似文献
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Heat transfer coefficients were measured on a horizontal platinum wire and converted to data on horizontal copper tubes. The
measurements spanned a large region of pressures p* = p/pcrit = 0.05–0.50 and heat fluxes of q = 103–1.5 × 105 W/m2. The preparation of the test equipment is described. The effects of pressure and concentration on the heat transfer coefficients
are shown. The mixture behaves very much like an azeotropic mixture; concentration has only a small effect, the heat transfer
coefficients can be obtained from the heat transfer coefficients of the pure components according to their molar fractions.
The conversion steps from wire- to tube-data are presented. A comparison of wire-data with correlations given in literature
is shown. It renders good agreement. 相似文献
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血液病与微量元素关系的研究 总被引:1,自引:0,他引:1
研究了血液病与微量元素的关系,发现再生障碍性贫血患者治疗前血清Cu升高(P〈0.05),缓解后Cu恢复正常。骨髓增生异常综合征(MDS)中RA+RAS组Cu及Cu/Zn比值高,Zn值降低不明显;RAEB+RAEB-T组Cu及Cu/Zn高,Zn值明显降低(P〈0.05)。急性白血病、淋巴瘤、多发性骨髓瘤及慢粒患者血清Cu、Zn及Cu/Zn比值与对照组比较均呈显著差异(P〈0.05 ̄0.01),而缓解 相似文献
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Using Langevin dynamics simulations, we investigate the dynamics of polymer translocation into a circular nanocontainer through a nanopore under a driving force F. We observe that the translocation probability initially increases and then saturates with increasing F, independent of φ, which is the average density of the whole chain in the nanocontainer. The translocation time distribution undergoes a transition from a Gaussian distribution to an asymmetric distribution with increasing φ. Moreover, we find a nonuniversal scaling exponent of the translocation time as chain length, depending on φ and F. These results are interpreted by the conformation of the translocated chain in the nanocontainer and the time of an individual segment passing through the pore during translocation. 相似文献
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A new bioprocess for production of sorbitol and gluconic acid from two low-cost feedstocks, inulin and cassava starch, using a commercially available enzyme was proposed in this study. The commercial glucoamylase GA-L NEW from Genencor was found to demonstrate a high inulinase activity for hydrolysis of inulin into fructose and glucose. The glucoamylase was used to replace the expensive and not commercially available inulinase enzyme for simultaneous saccharification of inulin and starch into high titer glucose and fructose hydrolysate. The glucose and fructose in the hydrolysate were converted into sorbitol and gluconic acid using immobilized whole cells of the recombinant Zymomonas mobilis strain. The high gluconic acid concentration of 193 g/L and sorbitol concentration of 180 g/L with the overall yield of 97.3 % were obtained in the batch operations. The present study provided a practical production method of sorbitol and gluconic acid from low cost feedstocks and enzymes. 相似文献
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Commercial pure wrought tungsten and 1060 pure aluminum can be joined by using induction‐heat deposition (IHD) welding with commercial pure copper transitional layer. The microstructures of W/Cu/Al interfaces have been studied by means of scanning electron microscope, energy dispersive X‐ray, and X‐ray diffraction. Results show that copper as the transitional metal could form good interfaces with both tungsten and aluminum by IHD under proper processing parameters. The metallic bonding of W/Cu obtained by Cu and W mutual diffusing at a quite limited range without any intermetallic compounds, while eutectic of α(Al)/θ(CuAl2) makes up Cu/Al interface. The average shear strength of W/Cu and Cu/Al interfaces are about 170 MPa and 55 Mpa, respectively, at room temperature. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
10.
The analysis of the through-space/bond interaction with
calculation is applied to the HOMO energy levels of propellane compounds. We could investigate molecular structural factors which dominate the height of the HOMO energy levels. 相似文献