[[alternative]]Synthesis and Characterization of Group 6 (M= Cr, Mo) Carbonyl Chalcogenides Complexes

[[abstract]][1] Se-Cr system Reflux of Se powder or SeO2、SeO32- with Cr(CO)6、Et4NBr in KOH/MeOH solution yields the closo-cluster [Et4N]2[Se2Cr3(CO)10]. [S2Cr3(CO)10]2- also an be prepared in the similar conditions. Further methylation of [Se2Cr3(CO)10]2- with MeSO3CF3 produces the selenium-methylated complex [MeSe{Cr(CO)5}3]- and {MeSeCr(CO)4}2 . However, the reactions of [Se2Cr3(CO)10]2- with RX (R = C3H3, X = Cl, Br; R = CH3, X = I) form the known mononuclear compounds [XCr(CO)5]- (X = Cl, Br, I) Further, reaction of [Se2Cr3(CO)10]2- with Fe(CO)5/KOH gives [SeFe3(CO)9]2-, while treatment with Ru3(CO)12 produces the octahedral complexes [HSe2Ru4(m-CO)2(CO)8]- and [Se2Ru4(m-CO)4(CO)8]2-. Be- sides, [Se2Cr3(CO)10]2- can react with 1 equiv. of Mo(CO)6 in acetone to produce the mixed-metal Cr/Mo cluster [Se2MoCr2(CO)10]2-. On the other hand, reaction of [Se2Cr3(CO)10]2- with excess Mo(CO)6 leads to formation of [Se2Mo3(CO)10]2- in good yield. When [Se2Cr3(CO)10]2- was treated with Mn(CO)5Br in acetone at room temperature, two different types of the unusual mixed-metal clusters [Me2CSe2Cr2Mn(CO)14]- and [Se2Cr2Mn3- (CO)20]- were produced. [2] Te-Cr system The reaction of Te powder with Cr(CO)6/KOH in a molar ratio of 1:2 in methanol solution forms [HTe{Cr(CO)5}2]- , which can rapidly transform into a highly reactive species [Et4N]2[Te{Cr(CO)5}2] by the addition of Et4NBr . However, the mono-methylated complex [MeTe{Cr(CO)5}2]- can be obtained by using NaOH under the similar conditions, where the methyl group is likely to come from the methanol solvent. The reaction of [Te{Cr(CO)5}2]2- with MeSO3CF3 only affords the double-methylated complex Me2Te{Cr(CO)5}2 . [Te{Cr(CO)5}2]2- rapidly transforms to give [X{TeCr2(CO)10}2]2- (X = O, CH2) upon the attack of O2 and CH2Cl2. Besides, the reaction of [Te{Cr(CO)5}2]2- with Cu(CH3CN)4BF4 produces the known compound [Te2Cr4(CO)20]2- while treatment of [Te{Cr(CO)5}2]2- with NaOH/MeOH gives another known compound [Te2Cr4(CO)18]2-. When Te powder reacts with Cr(CO)6/KOH in a molar ratio of 1: 3 in methanol solution, the product is found to rapidly transform into a new complex [CH2ClTe{Cr(CO)5}3]- upon the addition of CH2Cl2. [3] Te-Mo system Reflux of Te powder and Mo(CO)6 in KOH/MeOH solution forms the tire-shaped cluster [Te8Mo6(CO)18]2-, which contains three Te2Mo2 planes linking by Te22- group. This product can be also obtained from the reaction of Te powder with [Te2Mo4(CO)18]2- in the basic alcoholic solution. When [Te2Mo4(CO)18]2- was treated with H2C=CHCH2Br, the double-substituted complex [(C3H5)2Te2Mo2(CO)6] was obtained where the Mo(CO)5 moiety of [Te2Mo4(CO)18]2- is replaced by the incoming C3H5 group. The study herein describes the similarities and differences among the reactions of group 6 (Cr, Mo) carbonyls with group 16 chalcogen atoms (S, Se, Te) and discusses as well the effect of basicity and metal size on cluster formation.

New Cognition on Gini Coefficient from Statistics Implementation Point of View

文章从收集收入样本数据、到采用各种方法估算基尼系数、再到具体运用基尼系数进行收入差异评价的整个环节中,探讨了各个部分可能会出现的问题,以期能帮助我们如何用基尼系数客观地评判现实的经济生活。This thesis probes into all possible problems generated from income sample data collection,Gini coefficient estimation and its application in valuing income difference,so as to help us objectively value economic reality with Gini coefficient

RNA结合蛋白PTBP1与磷酸化-AXL共表达在骨肉瘤中的临床意义

目的探索RNA结合蛋白PTBP1与p-AXL在骨肉瘤中的表达情况及其临床病理联系，并进一步探讨PTBP1/p-AXL共表达在骨肉瘤中的预后评估意义。方法应用GEO和Target数据库分析PTBP1与AXL在骨肉瘤和正常组织中的表达差异及PTBP1的预后价值。收集2016年3月至2020年10月中山大学第一附属医院76例骨肉瘤和37例非恶性骨组织（骨痂、骨纤维结构不良或骨样骨瘤）及其病例信息，应用免疫组化法检测PTBP1和p-AXL蛋白的表达情况并行统计学分析。结果GEO数据库分析结果显示PTBP1和AXL在骨肉瘤组织的表达具有高于正常组织的趋势，但尚未达到统计学意义；Target数据分析结果显示PTBP1高表达组骨肉瘤患者总生存期（OS）与无进展生存期（PFS）均短于低表达组，但差异尚未达统计学意义（P=0.064； P=0.134）。免疫组化结果显示PTBP1和p-AXL蛋白的表达在骨肉瘤组织中显著高于非恶性骨组织；p-AXL阳性表达率与肺转移相关（P=0.025）；Kaplan-Meier分析发现肺转移、复发、PTBP1表达及PTBP1/p-AXL共表达等因素与骨肉瘤患者不良总生存期相关；且多变量Cox回归分析显示肺转移（P<0.000 1）、PTBP1表达阳性（P=0.041）是骨肉瘤患者总生存期（OS）独立危险因素；PTBP1/p-AXL共表达患者的OS（P=0.017）和PFS（P=0.043）均低于非PTBP1/p-AXL共表达患者。结论PTBP1、p-AXL在骨肉瘤中高表达，PTBP1与p-AXL共表达与患者预后差相关，且PTBP1可作为骨肉瘤患者独立预后指标

JUNO Sensitivity on Proton Decay p→νˉK+p\to \bar\nu K^+ Searches

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this paper, the potential on searching for proton decay in $p\to \bar\nu K^+$ mode with JUNO is investigated.The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits to suppress the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar\nu K^+$ is 36.9% with a background level of 0.2 events after 10 years of data taking. The estimated sensitivity based on 200 kton-years exposure is $9.6 \times 10^{33}$ years, competitive with the current best limits on the proton lifetime in this channel

JUNO sensitivity on proton decay p → ν K + searches*

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this study, the potential of searching for proton decay in the $p\to \bar{\nu} K^+$ mode with JUNO is investigated. The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits suppression of the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar{\nu} K^+$ is 36.9% ± 4.9% with a background level of $0.2\pm 0.05({\rm syst})\pm$$0.2({\rm stat})$ events after 10 years of data collection. The estimated sensitivity based on 200 kton-years of exposure is $9.6 \times 10^{33}$ years, which is competitive with the current best limits on the proton lifetime in this channel and complements the use of different detection technologies