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Controlled synthesis of porous spinel cobalt manganese oxides as efficient oxygen reduction reaction electrocatalysts

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Nano Research 2016年第1期9卷 207-213页

作者： Hongchao Yang Feng Hu Yejun zhang Liyi shi Qiangbin Wang Department of Chemistry Shanghai University 99 Shang-Da Road Shanghai200444 China Key Laboratory of Nano-Bio Interface Division of Nanobiomedicine and i-Lab Suzhou Institute of Nano-Tech and Nano-Bionics Chinese Academy of Sciences Suzhou 215123 China

In this article, we report a facile precursor pyrolysis method to prepare porous spinel-type cobalt manganese oxides （CoxMng-xO4） with controllable morphologies and crystalline structures. The capping agent in the reaction was found to be crucial on the formation of the porous spinel cobalt manganese oxides from cubic Co2MnO4 nanorods to tetragonal CoMn2O4 microspheres and tetragonal CoMn204 cubes, respectively. All of the prepared spinel materials exhibit brilliant oxygen reduction reaction （ORR） electrocatalysis along with high stability. In particular, the cubic Co2MnO4 nanorods show the best performance with an onset potential of 0.9 V and a half-wave potential of 0.72 V which are very close to the commercial Pt/C. Meanwhile, the cubic Co2MnO4 nanorods present superior stability with negligible degradation of their electrocatalytic activity after a continuous operation time of 10,000 seconds, which is much better than the commercial Pt/C electrocatalvst.

关键词： porous nanostructure cobalt manganese oxides electrocatalyst oxygen reduction reaction

Development of mechatronic driving system for seed meters equipped on conventional precision corn planter

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International Journal of Agricultural and Biological Engineering 2015年第4期8卷 1-9页

作者： Yang Li He Xiantao Cui Tao zhang Dongxing shi Song zhang Rui Wang Mantao College of Engineering China Agricultural UniversityBeijing 100083China

Precision planters are more and more widely used for planting corn in *** meters of conventional precision corn planters are usually driven by ground wheel and chain and sprocket system at *** of the slippage of ground wheels and vibration of chains,planting accuracy cannot be ensured,especially at higher forward *** improve the planting performance of precision planters,a mechatronic driving system was designed and its field working performance was evaluated in this research.A two-row pneumatic precision planter was modified to allow simultaneously using two different driving systems,i.e,with one row unit equipped with the newly designed mechatronic driving system and the other row unit equipped with conventional mechanical driving system,and used for planting at three forward speeds(9,11 and 12 km/h)on no-tillage and rotary-tillage *** distances between adjacent seeds in each plot were measured and the indices of uniformity in seed spacing,quality of feeding index(QFI),missing-seeding index and precision index were *** the average 4.70%increase of QFI and 3.54%decrease of missing-seeding index,the mechatronic driving system performed better than the mechanical driving system both on no-tillage and rotary-tillage lands at each forward *** values of QFI,missing-seeding index and precision index of the mechatronic driving system on rotary-tillage land are comparable to those on no-tillage land,by contrast,these indices of the mechanical driving system on rotary-tillage land are significantly worse than those on no-tillage *** result indicates that the mechatronic driving system can eliminate the effect of ground wheel slippage on planting quality and maintain the uniformity of seed *** the QFI,missing-seeding index and precision index become worse with the increase of forward speed,with the worst values of QFI of 89.93%,missing-seeding index of 5.08%and precision index of 18.92%at the highest forwar

关键词： precision planter seed meter mechatronic driving system control motor wheel slippage

Novel Synthetic Method for Triacetylbenzene

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Chinese Chemical Letters 2006年第9期17卷 1165-1168页

作者： Bin zhang Yong GAO Jian Li LI Zhen shi Department of Chemistry Northwest University Xi＇an 710069

Triacetylbenzene was prepared from tribenzimidazolium salt and Grignard reagent. The addition-hydrolysis reaction of tribenzimidazolium salt with Grignard reagent is reported and a novel method for preparation of tria... 详细信息

关键词： Triacetylbenzene tribenzimidazolium salt Grignard reagent synthesis.

Template/surfactant free and UV light irradiation assisted fabrication of Mn-Co oxides composite nanorings: Structure and synthesis mechanism

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Progress in Natural Science:Materials International 2019年第2期29卷 163-169页

作者： Wentao Jiang Xiaonan Hu Muhammad Yaseen Liyi shi Dengsong zhang Jianping zhang Lei Huang Research Center of Nano Science and Technology Shanghai University Institute of Chemical Sciences University of Peshawar

A facile, green, cost effective, and template or surfactant free strategy via a two-step route i.e. UV irradiation followed by dissolution-growth for the controlled synthesis of Mn-Co composite nanorings at room temperature was proposed. The nanorings structures and the process were systematically studied via TEM, HRTEM, EDX and XRD. Bir-MnO;nanosheets first formed through the direct photolysis of KMnO;under UV light irradiation. This was followed by a dissolution-growth process via the dissolution of Bir-MnO;nanosheets by the generated H;from the redox reaction between the added Co（NO;）;and residual KMnO;, as well as the accompanied formation of CoOOH, and Mn-Co composite nanorings. It was found that a balance between the dissolution and growth rate was needed. Suitable pH, KMnO;presence and the starting nanosheets like Bir-MnO;were the key factors for the formation of nanorings. The obtained Mn-Co nanorings/TiO;showed enhanced efficiency for the catalytic oxidation of HCHO. Based on the above understandings, it is believed that the developed dissolution-growth method can be adopted for the designing and preparation of other Mn-Co composite nanostructures which can be further applied for environmental pollution remediation.

关键词： KMnO4 irradiation Template free green synthesis MnO2 nanoring Co3O4 Structural characterization

添加造孔剂法制备多孔HAPw-nmZnO-nmCaO骨修复材料

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口腔颌面修复学杂志 2024年第2期25卷 119-125页

作者：孙士家赵强张文云徐州医科大学附属口腔医院徐州221000 联勤保障部队第九二〇医院口腔科昆明650000

目的:研讨使用添加造孔剂法制备多孔HAPw-nmZnO-nmCaO骨修复材料的最佳工艺条件。方法:将HAPw-nmZnO-nmCaO、聚甲基丙烯酸甲酯(PMMA)及硅胶经过模具成型与高温煅烧制作多孔骨修复材料,使用X射线衍射仪、扫描电镜、阿基米德排水法和万能... 详细信息

目的:研讨使用添加造孔剂法制备多孔HAPw-nmZnO-nmCaO骨修复材料的最佳工艺条件。方法:将HAPw-nmZnO-nmCaO、聚甲基丙烯酸甲酯(PMMA)及硅胶经过模具成型与高温煅烧制作多孔骨修复材料,使用X射线衍射仪、扫描电镜、阿基米德排水法和万能试验机对多孔骨修复材料进行相关测试,并探索多孔骨修复材料的体外降解性能和细胞毒性。结果:煅烧温度不能超越600℃;造孔剂占20%wt和煅烧温度600℃条件下制备的多孔HAPw-nmZnO-nmCaO骨修复材料具有较优的孔隙率(47%)和机械强度(2.6 MPa),适宜的降解速率和生物相容性。结论:本实验使用添加造孔剂法成功筛选出制备多孔HAPw-nmZnO-nmCaO骨修复材料的最佳工艺条件。

关键词：多孔骨修复材料羟基磷灰石晶须造孔剂法

三维超声血管斑块定量参数NWI、GSM对颈动脉斑块性质的评估价值

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河南医学研究 2024年第8期33卷 1423-1426页

作者：郭文博史景璐张嵘河南中医药大学第五临床医学院(郑州人民医院)超声医学科河南郑州450000 郑州市第七人民医院妇产科河南郑州450000

目的分析三维超声血管斑块定量参数标准化管壁指数(NWI)、灰阶中位数(GSM)对颈动脉斑块性质的评估价值。方法回顾性收集2019年6月至2022年11月108例于郑州人民医院接受颈动脉斑块超声检查的患者病历资料。根据病理检查结果分为稳定斑块... 详细信息

目的分析三维超声血管斑块定量参数标准化管壁指数(NWI)、灰阶中位数(GSM)对颈动脉斑块性质的评估价值。方法回顾性收集2019年6月至2022年11月108例于郑州人民医院接受颈动脉斑块超声检查的患者病历资料。根据病理检查结果分为稳定斑块组(51例)与易损斑块组(64例)。两组均接受三维超声血管斑块定量检测及颈动脉内膜剥脱术。比较发生易损斑块的影响因素,并分析三维超声血管斑块定量参数NWI、GSM对颈动脉斑块性质的评估价值。结果易损斑块体积、厚度、最大面积狭窄率及GSM低于稳定板块,NWI高于稳定斑块(P<0.05);经logistic回归分析显示,三维超声血管斑块定量参数NWI、GSM均为易损斑块的重要影响因素(P<0.05);经受试者工作特征曲线分析,三维超声血管斑块定量参数NWI评估颈动脉易损斑块的曲线下面积、特异度高于GSM,GSM评估颈动脉易损斑块的灵敏度高于NWI(P<0.05)。结论对颈动脉斑块患者采用三维超声血管斑块定量参数NWI、GSM检测,可帮助对斑块回声进行量化分析,同时也有利于对斑块累及血管负荷进行评估,对患者血管斑块具有较高的定性评估价值。

关键词：颈动脉斑块三维超声标准化管壁指数灰阶中位数

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Magnetically recyclable Pd/γ-AlOOH@Fe_3O_4 catalysts and their catalytic performance for the Heck coupling reaction

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Science China Chemistry 2014年第6期57卷 866-872页

作者： YANG Hao JI ShengFu LIU XueFei zhang DanNi shi Da State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology

Novel magnetically recyclable Pd/γ-AlOOH@Fe3O4 catalysts were prepared using γ-AlOOH@Fe3O4 as a magnetic supporter and nano-Pd particles as the active catalytic *** structure of the catalysts was characterized by X-ray diffraction(XRD),transmission electron microscopy(TEM),N2 adsorption-desorption,and a vibration sample magnetometer(VSM).The catalytic activity and recyclability for the Heck coupling reaction were *** showed that the magnetic γ-AlOOH@Fe3O4 possessed a core-shell structure,as well as that the nano-Pd particles were 6–8 nm and had been well dispersed in the γ-AlOOH *** the Heck coupling reactions,the magnetic Pd/γ-AlOOH@Fe3O4 catalysts exhibited good catalytic activity and *** the(0.021 mol%)Pd/γ-AlOOH@Fe3O4 catalyst,the bromobenzene conversion and product yield reached about 100%and 96.3%,respectively,under a 120°C reaction temperature and 12 h reaction *** being recycled 8 times,the conversion of bromobenzene and the recovery of the catalyst were about 90%and 93%,*** nano-Pd particles were kept well dispersed in the used Pd/γ-AlOOH@Fe3O4 catalyst.

关键词： magnetic Pd/γ-AlOOH@Fe3O4 Heck reaction recyclable

Seedling growth and metal accumulation of selected woody species in copper and lead/zinc mine tailings

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Journal of Environmental Sciences 2011年第2期23卷 266-274页

作者： Xiang shi Xiaolei zhang Guangcai Chen Yitai Chen Ling Wang Xiaoquan Shan Research Institute of Subtropical Forestry Chinese Academy of Forestry Fuyang 311400 China College of Forestry Shandong Agricultural University Taian 271018 China College of Agronomy and Biotechnology Yunnan Agricultural University Kunming 650201 China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Econvironmental Sciences Chinese Academy of Sciences Beijing 100085 China

A greenhouse pot experiment was conducted to evaluate the potential of selected woody plants for revegetation in copper （Cu） and lead/zinc （Pb/Zn） mine tailing areas. Five woody species （Amorpha fruticosa Linn, Vitex trifolia Linn. var. simplicifolia Chum, Glochidion puberum （Linn.） Hutch, Broussonetia papyrifera, and Styrax tonkinensis） and one herbaceous species （ Sesbania cannabina Pets） were planted in Cu and Pb/Zn tailings to assess their growth, root morphology, nutrition uptake, metal accumulation, and translocation in plants. Amorpha fruticosa maintained normal growth, while the other species demonstrated stress related growth and root development. Sesbania cannabina showed the highest biomass among the plants, although it decreased by 30% in Cu tailings and 40% in Pb/Zn railings. Calculated tolerance index （TI） values suggested that A. fruticosa, an N-fixing shrub, was the most tolerant species to both tailings （TI values 0.92-1.01）, while S. cannabina had a moderate TI of 0.65-0.81 and B. papyrifera was the most sensitive species, especially to Pb/Zn tailings （TI values 0.15-0.19）. Despite the high concentrations of heavy metals in the mine tailings and plants roots, only a small transfer of these elements to the aboveground parts of the woody plants was evident from the low translocation factor （TF） values. Among the woody plants, V. trifolia var. simplicifolia had the highest TF values for Zn （1.32）, Cu （0.78）, and Pb/Zn （0.78）. The results suggested that A. fruticosa and S. cannabina, which have the highest tolerance and biomass production, respectively, demonstrated the potential for tailings revegetation in southern China.

关键词： woody plants mine tailing tolerance revegetation root

lncRNA VPS9D1-AS1调节miR-331-3p/SERP1轴对宫颈癌细胞增殖、凋亡和侵袭的影响

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中国优生与遗传杂志 2024年第7期32卷 1343-1350页

作者：师媛张赞陈璐周满红西北妇女儿童医院陕西西安716000 延安大学咸阳医院陕西咸阳712000

目的探讨lncRNAVPS9D1-AS1对宫颈癌细胞恶性生物学行为的影响及作用机制。方法分析宫颈癌细胞和宫颈癌组织中lncRNAVPS9D1-AS1表达情况;将SiHa细胞分为si-NC组、si-VPS9D1-AS1组、si-VPS9D1-AS1+inhibitor-NC组、si-VPS9D1-AS1+miR-331-3p inhibitor组和control组,qRT-PCR检测转染效率;通过集落形成实验、流式细胞术、Transwell实验、宫颈癌细胞肿瘤异种移植生长等一系列功能实验研究lncRNAVPS9D1-AS1对宫颈癌的影响。采用荧光素酶报告基因法、蛋白质印迹法验证lncRNAVPS9D1-AS1与miR-331-3p、miR-331-3p与SERP1的靶向关系。结果 VPS9D1-AS1在宫颈癌组织和细胞中上调表达(P<0.05);与si-NC组比较,si-VPS9D1-AS1组SiHa细胞集落形成数、PCNA、SERP1表达、迁移与侵袭细胞数、MMP-2、MMP-9表达降低,细胞凋亡率、Cleaved Caspase-3表达升高(P<0.05);下调miR-331-3p可逆转VPS9D1-AS1敲低对SiHa细胞恶性行为的抑制作用(P<0.05);双荧光素酶报告基因实验证实miR-331-3p与lncRNA VPS9D1-AS1、miR-331-3p与SERP1存在靶向调控关系(P<0.05);裸鼠实验表明,体内抑制VPS9D1-AS1表达可显著降低移植瘤质量、体积、SERP1表达,升高miR-331-3p表达(P<0.05)。结论 lncRNA VPS9D1-AS1在宫颈癌组织和细胞中上调表达,敲低VPS9D1-AS1通过调节miR-331-3p/SERP1轴,抑制宫颈癌细胞的恶性进展。

关键词： lncRNA VPS9D1-AS1/miR-331-3p/SERP1轴宫颈癌增殖凋亡侵袭