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A Simulation of the Dependence of Tidal Interaction on Galaxy Type in Compact Groups

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2008年

作者：（英国）詹姆斯·巴里原

来源：汇雅图书（南通市图书馆... 评论

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International j.urnal of Astronomy and Astrophysics 2024年第2期14卷 85-100页

作者： Mark j. Henriksen Mateo Mej.a Department of Physics University of Maryland Baltimore USA

We have investigated the role that different galaxy types have in galaxy-galaxy interactions in compact groups. N-body simulations of 6 galaxies consisting of a differing mixture of galaxy types were run to compare the relative importance of galaxy population demographic on evolution. Three different groups with differing galaxy content were tested: all spiral, a single elliptical and 50% elliptical. Tidal interaction strength and duration were recorded to assess the importance of an interaction. A group with an equal number of spiral and elliptical galaxies has some of the longest and strongest interactions with elliptical-elliptical interactions being most significant. These elliptical-elliptical interactions are not dominated by a single large event but consist of multiple interactions. Elliptical galaxies tidally interacting with spiral galaxies, have the next strongest interaction events. For the case when a group only has a single elliptical, the largest magnitude tidal interaction is an elliptical on a spiral. Spirals interact with each other through many small interactions. For a spiral only group, the interactions are the weakest compared to the other group types. These spiral interactions are not dominated by any singular event that might be expected to lead to a merger but are more of an ongoing harassment. These results suggest that within a compact group, early type galaxies will not form via merger out of an assemblage of spiral galaxies but rather that compact groups, in effect form around an early type galaxy.

关键词： Galaxy Groups Galaxy Clusters Galaxy Evolution N-Body Simulations

吩噁噻基二氟甲基锍盐:一种多功能亲电二氟甲基试剂

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中国科学：化学 2024年第6期54卷 811-812页

作者：聂晶马军安天津大学化学系天津300072

在各种含氟取代基中,二氟甲基(CF_(2)H)是一个重要和耐人寻味的基团.它是一种良好的氢键供体,常用作-SH、-CH_(2)OH和-NH_(2)等基团的生物电子等排体,且具有良好的亲脂性.由此可以增强药物分子与靶标间的亲和力,提高药物分子的代谢稳定... 详细信息

在各种含氟取代基中,二氟甲基(CF_(2)H)是一个重要和耐人寻味的基团.它是一种良好的氢键供体,常用作-SH、-CH_(2)OH和-NH_(2)等基团的生物电子等排体,且具有良好的亲脂性.由此可以增强药物分子与靶标间的亲和力,提高药物分子的代谢稳定性和生物利用度,在化学合成和药物研究中引起了广泛兴趣.

关键词：药物分子生物利用度亲脂性化学合成亲和力

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读写月报 2024年第1期 56-56页

作者： [美]拜伦·凯蒂史蒂芬·米切尔周玲莹(译) 若水(译) 不详

做决定是很容易的,只有你为决定所编的故事才显得困难重重。当你跳伞时,你扯开降落伞的绳索但它没有打开,你会害怕,因为千钧一发之间必须赶紧拉另一条绳索。当你不假思索地拉了那条绳索,降落伞仍没打开,那已是最后一条绳索了。这一刻,... 详细信息

做决定是很容易的,只有你为决定所编的故事才显得困难重重。当你跳伞时,你扯开降落伞的绳索但它没有打开,你会害怕,因为千钧一发之间必须赶紧拉另一条绳索。当你不假思索地拉了那条绳索,降落伞仍没打开,那已是最后一条绳索了。这一刻,你无计可施了。

关键词：降落伞绳索故事

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经济发展计划体系在中国的回归:论韩博天、麦尔敦和胡鞍钢的研究

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开放时代 2013年第6期 38-45页

作者：巴里·诺顿杨帆(译) 美国加利福尼亚大学圣地亚哥校区国际关系与太平洋研究学院

韩博天和奥利佛·麦尔敦的研究向我们展示出规划过程是如何深深融入中国政治体系的各个方面,特别是政策的制定和执行过程,以及干部考核体系。胡鞍钢也指出规划的制定是一个信息抽取和整合的过程,自上而下的沟通机制才是更关键并具有深... 详细信息

韩博天和奥利佛·麦尔敦的研究向我们展示出规划过程是如何深深融入中国政治体系的各个方面,特别是政策的制定和执行过程,以及干部考核体系。胡鞍钢也指出规划的制定是一个信息抽取和整合的过程,自上而下的沟通机制才是更关键并具有深远意义的。但要想理解规划的过程,就必须明确它的目标、手段,以及参与其中的政府机构,在这方面这些论文还待进一步明确。2003年之后规划的增多是否提高了中国整体经济的灵活性和高度?是否有助于其走向理想的发展道路?在这个问题上,笔者并没有被说服。

关键词：计划规划经济发展能源强度可观测性拟合程度

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Laser processing effects on Ti−45Nb alloy surface,corrosive and biocompatible properties

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Transactions of Nonferrous Metals Society of China 2024年第8期34卷 2533-2551页

作者： I.CVIj.VIĆ-ALAGIĆ S.LAKETIĆ M.MOMČILOVIĆ j.CIGANOVIĆ Đ.VELj.VIĆ j.BAj.T V.KOj.Ć M.RAKIN Vinča Institute of Nuclear Sciences-National Institute of the Republic of Serbia University of BelgradeP.O.Box 52211001 BelgradeSerbia Faculty of Technology and Metallurgy University of BelgradeKarnegijeva 411120 BelgradeSerbia Oncology Institute of Voj.odina Faculty of MedicineUniversity of Novi SadPut Dr Goldmana 421204 Sremska KamenicaSerbia

The Ti−45Nb(wt.%)alloy properties were investigated in relation to its potential biomedical *** surface modification was utilized to improve its performance in biological *** a result of the laser treatment,(Ti,Nb)O scale was formed and various morphological features appeared on the alloy *** electrochemical behavior of Ti−45Nb alloy in simulated body conditions was evaluated and showed that the alloy was highly resistant to corrosion deterioration regardless of additional laser surface modification ***,the improved corrosion resistance after laser treatment was evident(the corrosion current density of the alloy before laser irradiation was 2.84×10^(−8)A/cm^(2),while that after laser treatment with 5 mj.was 0.65×10^(−8)A/cm^(2))and ascribed to the rapid formation of a complex and passivating bi-modal surface oxide *** cytotoxicity and effects of the Ti−45Nb alloy laser surface modification on the MRC-5 cell viability,morphology,and proliferation were also *** Ti−45Nb alloy showed no cytotoxic ***,cells showed improved viability and adherence to the alloy surface after the laser irradiation *** highest average cell viability of 115.37%was attained for the alloy laser-irradiated with 15 *** showed that the laser surface modification can be successfully utilized to significantly improve alloy performance in a biological environment.

关键词： Ti−45Nb alloy laser surface scanning electrochemical properties biocompatibility cell morphology

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