Plasmonic coupling-enhanced in situ photothermal nanoreactor with shape selective catalysis for C-C coupling reaction

Carbon-carbon (C-C) coupling reactions represent one of the most powerful tools for the synthesis of complex natural products, bioactive molecules developed as drugs and agrochemicals. In this work, a multifunctional nanoreactor for C-C coupling reaction was successfully fabricated via encapsulating the core-shell Cu@Ni nanocubes into ZIF-8 (Cu@Ni@ZIF-8). In this nanoreactor, Ni shell of the core-shell Cu@Ni nanocubes was the catalytical active center, and Cu core was in situ heating source for the catalyst by absorbing the visible light. Moreover, benefiting from the plasmonic resonance effect between Cu@Ni nanocubes encapsulated in ZIF-8, the absorption range of nanoreactor was widened and the utilization rate of visible light was enhanced. Most importantly, the microporous structure of ZIF-8 provided shape-selective of reactant. This composite was used for the highly shape-selective and stable photocatalysed C-C coupling reaction of boric acid under visible light irradiation. After five cycles, the nanoreactor still remained high catalytical activity. This Cu@Ni@ZIF-8 nanoreactor opens a way for photocatalytic C-C coupling reactions with shape-selectivity.

     

浅议监理队伍素质对公路建设监理工作影响

浅议我国目前公路施工监理队伍现状,如何提高监理人员业务水平和素质,其素质高低直接影响公路建设监理工作质量,提高监理队伍素质具有重要现实意义.     

地球科学的发展历史及研究方向探讨

通过对地球科学发展历史的回顾 ,阐述了地球科学中的全球变化科学、城市环境、工程地质等现阶段研究状况 ,并对其将来研究方向进行了探讨 ,以便探求人类的应对策略     

Further study on the flexural behaviour of concrete-filled steel tubes

This paper is a further study on the flexural behaviour of concrete-filled steel tubes based on the former work presented by Han [Han LH. Flexural behaviour of concrete-filled steel tubes. Journal of Constructional Steel Research 2004;60(2):313-37]. A total of 36 composite beam specimens filled with self-consolidating concrete (SCC) were tested. The main parameters varied in the tests are: (1) sectional types (circular and square); (2) steel yielding strength (from 235 to 282 MPa); (3) the ratio of tube diameter (or width) to wall thickness, D/t (from 47 to 105), and (4) the ratio of shear span to depth (from 1.25 to 6). Comparisons are made with predicted beam capacities using the existing methods, such as AIJ-1997 [Architectural Institute of Japan (AIJ). Recommendations for design and construction of concrete filled steel tubular structures. 1997], AISC-LRFD-1999 [AISC. Load and resistance factor design specification for structural steel buildings. Chicago: American Institute of Steel Construction, Inc.; 1999], BS5400-1979 [British Standard Institute: BS5400, Part 5, Concrete and composite bridges. 1979], EC4-1994 [Eurocode 4. Design of composite steel and concrete structures, Part 1.1: General rules and rules for buildings (together with United Kingdom National Application Document). DD ENV 1994-1-1:1994. London W1A2BS: British Standards Institution; 1994] and the method proposed by Han [Han LH. Flexural behaviour of concrete-filled steel tubes. Journal of Constructional Steel Research 2004;60(2):313-37].Applied calculation formulae of moment versus curvature curves and the flexural stiffness of concrete-filled steel tubular (CFST) beams are presented, based on the mechanics model of Han [Han LH. Flexural behaviour of concrete-filled steel tubes. Journal of Constructional Steel Research 2004;60(2):313-37]. Comparisons are made with predicted beam flexural stiffness using different methods, such as AIJ-1997, AISC-LRFD-1999, BS5400-1979, EC4-1994 and the method proposed in this paper. Comparisons are also made between the simplified model and the mechanics model, and generally good agreement is achieved.     

摇曳的灯光

一件能够和办公区域产生实时互动联系的艺术品。     

城市道路绿化景观设计——以潍坊市宝通街为例

城市道路的绿化景观设计体现一个城市的人文环境,反映一个城市的发展水平,越来越受到人们重视。详细介绍了潍坊市宝通街绿化景观设计情况,可供设计人员参考。     

门式刚架轻型钢结构风荷载设计

对《门式刚架轻型房屋钢结构技术规程》(CECS102:2002)风荷载设计进行了阐述,并与《建筑结构荷载规范》(GB 50009-2001)进行了对比,提出了门式刚架抗风设计中需要注意的一些问题,可供设计参考.     

油管传输射孔(TCP)用尾声信号弹的研究

针对深井油管传输射孔作业中TCP监测识别系统无法监测到尾声信号弹发出的震动信号,同时存在尾声信号弹造成遇卡事故等问题,对尾声信号弹结构进行研究。通过ANSYS LS-DYNA仿真分析和地面试验验证,确定主装药采用分散装药,相比集中装药减轻了爆炸产物对本体的冲击,提升了主装药装药量。此外,本体采用非对称圆形泄压孔设计方案(一侧为φ8mm圆孔、另一侧为大于φ14mm圆孔)。地面试验结果表明该设计的外径胀大尺寸满足要求,有效减少了尾声信号弹的爆炸碎屑,降低了射孔管串在上提时遇卡的风险。大庆油田的使用效果说明其有效提升了TCP监测系统监测的成功率。     

Effects of Ca2+, Mg2+, Na+, and K+ substitutions on the microstructure and electrical properties of GdCoO3 ceramics

Journal of Electroceramics - GdCoO3-δ, Gd0.975Na0.025CoO3-δ, Gd0.98K0.02CoO3-δ, Gd0.98Ca0.02CoO3-δ, and GdCo0.99Mg0.01O3-δ ceramics were prepared via a solid-state reaction...