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A Co-N/C hollow-sphere electrocatalyst derived from a metanilic CoAl layered double hydroxide for the oxygen reduction reaction, and its active sites in various pH media

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Nano Research 2017年第7期10卷 2508-2518页

作者： Jun Wang Liqun Li Xu Chen yanluo lu Wensheng Yang Xue Duan State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing 100029 China

Transition-metal-coordinating nitrogen-doped carbon catalysts （M-N/C, M = Co, Fe, Mn, Ni, etc.） are considered one of the most promising nonprecious-metal electrocatalysts for the oxygen reduction reaction （ORR）. However, they suffer from low ORR catalytic activity, and their active sites have not been fully identified. Herein, we report the synthesis of a porous Co-N/C hollow-sphere electrocatalyst by carbonization of metanilic anions between the layers of a Co-A1 layered double hydroxide. The as-prepared Co-N/C catalyst exhibited excellent ORR catalytic activity with a high half-wave potential and a large diffusion-limited current in alkaline and neutral solutions. The performance of the catalyst was comparable to those of commercial Pt/C electrocatalysts. Through investigating the effects of mask ions （SCN- and F-） on the ORR activity of the Co-N/C catalyst, and comparing the ORR activity before and after the destruction of Co-Nx sites in different pH media, we concluded that the Co-Nx sites act directly as the ORR active sites in acidic and neutral solutions, but have a negligible effect on the ORR activity in alkaline conditions.

关键词： confined space hollow carbon sphere hierarchical pore structure electrocatalysts oxygen reduction reaction

Selective formation of luminescent chiral cocrystal:Molecular self-assembly of 2,20-binaphthol and 2-(3-pyridyl)-1H-benzimidazole

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Chinese Chemical Letters 2018年第10期29卷 1541-1543页

作者： yanluo lu Yanqun Tang Heyang Lin Xiaoyu Fang Bo lu Dan Li Dongpeng Yan State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Key Laboratory of Theoretical and Computational Photochemistry Ministry of EducationCollege of ChemistryBeijing Normal University

luminescent cocrystals have been received much attention in fluorescence imaging and sensor application. In this work, we report that the high-quality chiral luminescent cocrystal can be obtained through a molecular self-assembly process of 2,20-binaphthol and 2-（3-pyridyl）-1 H-benzimidazole. The assembly modes and stacking fashions of as-obtained cocrystal were determined by single crystal X-ray diffractometer. The structure and optical properties of the cocrystals were characterized by fluorescence emission, fluorescence decay, Raman and circular dichroism spectra. The results show that both the pristine co-assembled units（R-BINOL and S-BINOL） give rise to the R conformation within the final cocrystal, suggesting that the formation of cocrystal can be an effective way to achieve R/S-isomeric transformation of 2,20-binaphthol. It is also expected that the co-crystallization approach has much flexibility and potential applications for the design and selective formation of chiral luminescent materials.

关键词： Chiral cocrystal Molecular self-assembly Binaphthol

基于铂纳米颗粒电沉积镁铝水滑石修饰电极的电化学葡萄糖生物传感器

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高等学校化学学报 2016年第3期37卷 442-447页

作者：徐亮林有芹陈旭路艳罗杨文胜北京化工大学化工资源有效利用国家重点实验室北京100029

采用成核/晶化隔离法合成了镁铝水滑石纳米颗粒,将其修饰到氧化铟锡导电玻璃电极表面;在此修饰电极基础上,利用电沉积还原氯铂酸盐法制备了铂纳米颗粒/水滑石复合修饰电极.由于水滑石层板表面的外限域作用有效抑制了铂纳米颗粒的聚集,... 详细信息

采用成核/晶化隔离法合成了镁铝水滑石纳米颗粒,将其修饰到氧化铟锡导电玻璃电极表面;在此修饰电极基础上,利用电沉积还原氯铂酸盐法制备了铂纳米颗粒/水滑石复合修饰电极.由于水滑石层板表面的外限域作用有效抑制了铂纳米颗粒的聚集,使该电极对过氧化氢具有较好的电催化性能.基于镁铝水滑石良好的生物相容性,将葡萄糖氧化酶进一步修饰到该电极表面,实现了对葡萄糖高灵敏的电化学检测,检出限(S/N=3)达1.0μmol/L.

关键词：铂纳米颗粒镁铝水滑石电沉积电化学葡萄糖生物传感器

O2结构Li_y[Mn_(1-x)M_x]O_2(M=Cr,Mg)的合成及结构研究

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化学学报 2003年第6期61卷 858-862页

作者：路艳罗卫敏杨文胜 EVANS D.G. 段雪北京化工大学可控化学反应科学与技术基础教育部重点实验室北京100029

由高温焙烧法制备层状前驱体Na2 /3 [Mn1-xMx]O2 (M =Cr,Mg) ,再经离子交换反应得到层状O2结构产物Liy [Mn1-xMx]O2 .XRD表明Liy[Mn1-xMx]O2 属六方晶系 ,P3ml空间群 .Cr的添加量对前驱体的晶体结构有很大影响 :随着x值的增大 ,前驱体... 详细信息

由高温焙烧法制备层状前驱体Na2 /3 [Mn1-xMx]O2 (M =Cr,Mg) ,再经离子交换反应得到层状O2结构产物Liy [Mn1-xMx]O2 .XRD表明Liy[Mn1-xMx]O2 属六方晶系 ,P3ml空间群 .Cr的添加量对前驱体的晶体结构有很大影响 :随着x值的增大 ,前驱体逐渐由层状P2结构Na2 /3 [Mn1-xCrx]O2 向正交结构Na4Mn9O18转变 .由SEM可以看到样品Liy[Mn1-xCrx] O2 (x≤ 0 .0 5 )具有六方层状结构 .XPS分析结果表明样品Liy[Mn0 .95Cr0 .0 5]O2 表面上的Mn和Cr分别以Mn4+和Cr4+存在 ,并且表面中Cr相对含量高于体相 ,而样品Liy[Mn0 .90 Mg0 .10 ]O2 的表面Mn和Mg分别以Mn4+和Mg2 +存在。

关键词：层状材料晶体结构合成表面分析锂锰复合氧化物锂离子二次电池正极材料氧分子

深圳市一起新型冠状病毒Omicron BF.7变异株暴发疫情的流行病学特征

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中华流行病学杂志 2023年第3期44卷 379-385页

作者：程雁鹏孔东锋张佳吕子全陈志高熊华威路滟罗青山吕秋莹赵锦温莹万佳陆芳芳逯建华邹旋张振深圳市疾病预防控制中心传染病预防控制所深圳518055 深圳市疾病预防控制中心中心实验室深圳518055 深圳市疾病预防控制中心艾滋病预防控制所深圳518055 深圳市宝安区公共卫生福永分中心深圳518103 深圳市疾病预防控制中心办公室深圳518055

目的分析深圳市一起广东省外输入的新型冠状病毒(新冠病毒)Omicron BF.7变异株所致暴发疫情的流行病学特征,梳理和分析其传播链条和传播特征。方法采用现场流行病学方法对病例进行调查,整理新冠病毒感染者活动轨迹、分析代际关系等,对... 详细信息

目的分析深圳市一起广东省外输入的新型冠状病毒(新冠病毒)Omicron BF.7变异株所致暴发疫情的流行病学特征,梳理和分析其传播链条和传播特征。方法采用现场流行病学方法对病例进行调查,整理新冠病毒感染者活动轨迹、分析代际关系等,对新冠病毒核酸阳性标本进行基因测序分析。结果2022年10月8-23日,深圳市共报告196例新冠病毒感染者,均存在流行病学关联。男、女性分别为100和96例,年龄M(Q_(1),Q_(3))为33(25,46)岁。本起疫情由在广东省外旅游返回深圳市的新冠病毒感染者(首发病例)引起,4条传播链分别为首发病例现住址相关感染8例、7日晚社会面活动相关感染65例、8日写字楼工作场所相关感染累计48例、在工作场所附近的写字楼相关感染74例。本起疫情潜伏期M(Q_(1),Q_(3))为1.44(1.11,2.17)d。室内暴露的潜伏期短于室外暴露的潜伏期,M(Q_(1),Q_(3))分别为1.38(1.06,1.84)和1.95(1.22,2.99)d,差异有统计学意义(Waldχ^(2)=10.27,P=0.001)。随着代际的增加,基因位点突变个数及突变比例增加。在同一传播链疫情时,传播1代的新增基因突变位点1~3个的占比较高。结论本起疫情传播链清晰,新冠病毒Omicron BF.7变异株的潜伏期短,传播速度快,基因突变比例较高。在疫情处置时,应加快疫情处置速度,严格落实防控政策。

关键词：新型冠状病毒感染新型冠状病毒 Omicron变异株流行病学特征传播链

Incidence and treatment of hepatic artery complications after orthotopic liver transplantation

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World Journal of Gastroenterology 2003年第12期9卷 2853-2855页

作者： Ji-ChunZhao Shi-Chunlu lu-NanYan BoLi Tian-FuWen YongZeng Nan-ShengCheng JingWang yanluo Yu-LanPen DepartmentofGeneralSurgery WestChinaHospitalSichuanUniversityChengdu610041SichuanProvinceChina DepartmentofUltrasoundDiagnosis WestChinaHospitalSichuanUniversityChengdu610041SichuanProvinceChina

AIM: To investigate the incidence and treatment of hepatic artery complications after orthotopic liver ***: From February 1999 to May 2002, orthotopic liver transplantations (OLT) were performed in 72 patients with end-stage liver diseases with an average age of 40.2±13.6years (ranged from 11 to 68 years), 56 were males and 16 females. The preoperative evaluation for the 72 patients was performed using duplexsonography, abdominal CT scan,and angiography of the hepatic artery. All donor grafts were perfused and preserved in University of Wisconsin solution at 4 ℃. OLT was performed with standard techniques with or without a veno-venous bypass. Reconstructions of hepatic artery were performed between the branch patches of gastroduodenal/hepatic or splenic/common hepatic artery confluence of the donors and recipients, and an end-to-end anastomosis between other arterial vessels of the donors and recipients was done. Arterial anastomosis was performed with interrupted 7-0/8-0 monofilament polypropylene suture under 3.5 x loupe magnification. Diagnosis of the complications of hepatic artery after OLT was based on the clinical presentations, ultrasound findings and arterial angiography. All patients were followed up regularly for duplex ultrasound scan after ***: The overall incidence of arterial complications in 72 patients after OLTs was 1.4 % (1/72). One 3 cm pseudoaneurysm at the side of anastomotic site of hepatic artery was found by urgent arteriogram due to hemoperitoneum secondary to bile leakage after *** the pseudoaneurysm was successfully embolized and the blood flow toward the donor liver in hepatic artery remained. The overall postoperative 30-day mortality rate was 8.33 %. The one-year survival rate was 83.72 % in 50 patients with benign diseases and was 71.43 % in 22 patients with malignant diseases following OLT. No death associated with complications of hepatic artery ***: Careful preoperative

关键词：常位肝移植肝动脉并发症血管重构 CT检查