不同Ce/Mn摩尔比对CeO_2-MnO_x催化剂低温NH_3选择性催化还原NO的影响

以高锰酸钾和硝酸锰为锰源,采用改进的共沉淀法制备了不同Ce/Mn摩尔比的Ce O2-Mn Ox催化剂.以NH3为还原剂,考察了催化剂低温(小于150℃)NH3选择性催化还原NO的性能.并采用XRD,BET,H2-TPR,NH3-TPD和XPS等手段对催化剂的物理化学性质进行表征.结果表明,Ce O2-Mn Ox催化剂在50~150℃温度区间内表现出了良好的催化活性.引入适量的Ce可以有效地改变催化剂的晶粒大小,增强其氧化还原能力;而Mn的加入,促进了其低温SCR活性.当Ce/Mn摩尔比为1∶3时(C1M3),低温活性最佳,在82~150℃温度区间内NO去除率达到90%以上,这主要是由于C1M3催化剂有较高含量的表面吸附氧、大量的弱酸性位点、良好的氧化还原性能以及表面较高含量的Mn4+物种.     

新型异长叶烷基二氢嘧啶硫酮类衍生物的合成及其抗肿瘤活性研究（英文）

以异长叶烷酮为起始物,经羟醛缩合、环化等手段,合成了12种异长叶烷基二氢嘧啶硫酮类衍生物,通过~1H NMR、~(13)C NMR及高分辨质谱(HRMS)对其结构进行了表征,通过X射线衍射分析测定了化合物3e的晶体结构.探索了这些衍生物对人乳腺癌细胞(MDA-MB-231)、人宫颈癌细胞(HeLa)、人肝癌细胞(Hep G-2)等三种癌细胞和一种正常细胞即小鼠巨噬细胞(RAW-264.7)的体外抗增殖活性.结果表明,这12种化合物显示出较好的抗肿瘤活性,其IC_(50)值在3.12～44.28μmol/L范围内.其中,化合物3j对MDA-MB-231细胞表现出最强的抗肿瘤活性(IC_(50)=3.12μmol/L),化合物3g对He La细胞表现出最强的抗肿瘤活性(IC_(50)=4.04μmol/L),化合物3k对Hep G-2细胞表现出最强的抗肿瘤活性(IC_(50)=5.43μmol/L).此外,化合物3j将MDA-MB-231细胞阻滞在G0/G1期,并以剂量依赖的方式诱导MDA-MB-231细胞的早期凋亡.     

Kondo screening cloud in a superconductor with mixed s-wave and p-wave pairing states

We study the Kondo screening of a spin-1/2 magnetic impurity coupled to a superconductor, which is fabricated by combination of an s-wave superconductor, a ferromagnet and a semiconductor with Rashba spin—orbit coupling (RSOC). The proximity induced superconducting states include the s-wave and p-wave pairing components with the aids of RSOC, and the ferromagnet induces a Zeeman field which removes the spin degeneracy of the quasiparticles in the triplet states. Thus, the Kondo screening of magnetic impurity involves the orbital degrees of freedom, and is also affected by the Zeeman field. Using the variational method, we calculate the binding energy and the spin—spin correlation between the magnetic impurity and the electrons in the coexisting s-wave and p-wave pairing states. We find that Kondo singlet forms more easily with stronger RSOC, but Zeeman field in general decreases the binding energy. The spin—spin correlation decays fast in the vicinity of the magnetic impurity. Due to the RSOC, the spatial spin—spin correlation becomes highly anisotropic, and the Zeeman field can induce extra asymmetry to the off-diagonal components of the spin—spin correlation. Our study can offer some insights into the studies of extrinsic topological superconductors fabricated from the hybrid structures containing chains of magnetic impurities.     

膀胱癌血清及尿液代谢组学研究

应用代谢组学研究方法,对与膀胱癌(Bladder cancer,BC)发病相关的生物标志物进行筛选,采用液相色谱-电喷雾质谱(LC-ESI/MS)联用技术对20名膀胱癌患者与24名正常人的血清和尿液进行研究.多变量统计分析结果表明,膀胱癌患者和正常人聚类明显,血清和尿液中分别发现13个潜在标志物.其中,(2E,6E,8E)-二十二碳三烯-1-醇、7-((1S,2S)-2-(庚胺)环己基)庚酸和(11E,14E,17E)-三烯-二十碳-1-醇首次在血清中发现,有潜力成为膀胱癌诊断标志物.液相色谱-质谱联用结合多变量分析的代谢组学研究技术在膀胱癌诊断中展现出巨大潜力.