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国际直线对撞机(ILC)正电子靶沉积的热功率将超过20 kW,传统的冷却方式已无法满足要求。美国Argonne国家实验室提出了摩擦接触热传导冷却的方法。根据Argonne实验室的研究方案,设计了一种旋转摩擦接触冷却的简化装置,根据热传导理论,结合ANSYS软件模拟了旋转冷却过程中的温度分布,理论上验证了方法的可行性。按照模拟的参数和结果,进行了摩擦接触热传导冷却实验,通过实验结果和数据分析证实了,低温区(20℃~50℃)有良好的冷却效应,初步验证了摩擦接触热传导冷却方案的有效性。A new scheme that cooling international Linear Collider (ILC) positron source target by touching thermal conduction (TTC) is presented by Argonne National Laboratory (ANL).Recent results of simulation for cooling the iron targets with 300 and 450 W heat reservoir by ANSYS and experiment of cooling the iron target with 300 and 450 W friction heat reservoir at Institute of Modern Physics (IMP),Chinese Academy of Sciences (CAS),have proved that the TTC has good cooling effect in low temperature zone (20℃~50℃),and preliminarily verified the feasibility of TTC for cooling the ILC positron source target. 相似文献
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Townsend SD Tan Z Dong S Shang S Brailsford JA Danishefsky SJ 《Journal of the American Chemical Society》2012,134(8):3912-3916
Application of native chemical ligation logic to the case of an N-terminal proline is described. Two approaches were studied. One involved incorporation of a 3R-substituted thiyl-proline derivative. Improved results were obtained from a 3R-substituted selenol function, incorporated in the context of an oxidized dimer. 相似文献
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The fullerendiol C60(OH)2(OOt-Bu)4 1 reacts with various arylboronic acids ArB(OH)2 to form fullerene-containing boronic esters C60(O2BAr)(OOt-Bu)4 in up to 95% yield depending on the structure of aryl group. Bis(pinacolato)diboron (B(OCMe2)2)2 also reacts with 1 to form C60(O2BB(OCMe2)2)(OOt-Bu)4. The bisboronic ester C60(O)(O2BAr)2(OOt-Bu)2 was also obtained starting from a tetrahydroxyl fullerene derivative C60(O)(OH)4(OOt-Bu)2. The fullerenyl boronic esters are moderately stable in air. Single crystal X-ray structure of C60(O2BPh)(OOt-Bu)4 was obtained. 相似文献
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Five meso-substituted cobalt(III) corroles were examined as to their catalytic activity for the electoreduction of O(2) when coated on an edge-plane pyrolytic graphite electrode in 1.0 M HClO(4). The investigated compounds are represented as (TpRPCor)Co(PPh(3)), where TpRPCor is the trianion of a para-substituted triphenylcorrole and R = OMe, Me, H, F, or Cl. Three electrochemical techniques, cyclic voltammetry, linear sweep voltammetry with a rotating disk electrode (RDE), and voltammetry at a rotating ring disk electrode (RRDE), were utilized to evaluate the catalytic activity of the corroles in the reduction of O(2). Cobalt corroles containing electron-withdrawing substituents were shown to be better catalysts than those having electron-donating groups on the three meso-phenyl rings of the triarylcorroles. 相似文献
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