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161.
162.
Jian Zhang Zhao‐Ji Li Yi‐Hang Wen Yao Kang Jian‐Kai Cheng Yuan‐Gen Yao 《无机化学与普通化学杂志》2004,630(15):2731-2735
Two new metal succinates modified by rigid bipyridines, Cd(4, 4′‐bpy)(C4H4O4)·1/4H2O ( 1 ) and Cu(2, 2′‐bpy)(C4H4O4)0.5(NO3)(H2O) ( 2 ) (bpy = bipyridine), have been synthesized by hydrothermal reactions and structurally determined. Complex 1 crystallizes in the orthorhombic space group Cmca with the cell parameters a = 11.696(2), b = 15.554(2), c = 15.874(3) Å, α = β = γ = 90.00°, V = 2888(3) Å3, Z = 8. Complex 2 crystallizes in the triclinic space group with a = 7.077(1), b = 9.838(2), c = 10.461(2) Å, α = 71.941(3)°, β = 73.078(3)°, γ = 74.502(3)°, V = 649.8(2) Å3, Z = 2. In complex 1 , a 2‐D network was formed by Cd‐succinato bonding. The 2‐D networks are pillared by 4, 4′‐bpy ligands, forming a 3‐D grid framework. The 2‐fold interpenetration of the resulting 3‐D frameworks completes the molecular structure. In complex 2 , the CuII atom adopts a distorted octahedral in which the CuII atoms are bridged by two H2O molecules into an infinite zigzag chain, [Cu2(H2O)2(C4H4O4)]n. The neighboring chains are further linked by π‐π stacking interactions into a 2‐D network, and the interlayer hydrogen bonds lead to the final 3‐D crystal structure. 相似文献
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Hang Ma Yang He Ruo-Feng Huang Xiao-Hui Zhang Jing Pan Jia-Qiang Li Chao He Xue-Ge Ling Xuan-Lun Wang Yan Xiong 《中国化学快报》2014,25(10):1327-1330
Under neat conditions,an efficient method for synthesis of imidoesters has been developed using cyanatobenzenes and dicarbonyl compounds.Nucleophilic addition spontaneously occurred between the two kinds of materials at room temperature with yields of up to 90%.A mechanism directed towards to the imidoester formation has been proposed. 相似文献
165.
Tianyong Liu Qian Dang Xunhui Zhou Jin Li Zhen Ge Hang Che Prof. Shaobin Tang Prof. Yi Luo Prof. Jun Jiang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(23):6945-6953
Developing the low-cost and efficient single-atom catalysts (SACs) for nitrogen reduction reaction (NRR) is of great importance while remains as a great challenge. The catalytic activity, selectivity and durability are all fundamentally related to the elaborate coordination environment of SACs. Using first-principles calculations, we investigated the SACs with single transition metal (TM) atom supported on defective boron carbide nitride nanotubes (BCNTs) as NRR electrocatalysts. Our results suggest that boron-vacancy defects on BCNTs can strongly immobilize TM atoms with large enough binding energy and high thermal/structural stability. Importantly, the synergistic effect of boron nitride (BN) and carbon domains comes up with the modifications of the charge polarization of single-TM-atom active site and the electronic properties of material, which has been proven to be the essential key to promote N2 adsorption, activation, and reduction. Specifically, six SACs (namely V, Mn, Fe, Mo, Ru, and W atoms embedded into defective BCNTs) can be used as promising candidates for NRR electrocatalysts as their NRR activity is higher than the state-of-the art Ru(0001) catalyst. In particular, single Mo atom supported on defective BCNTs with large tube diameter possesses the highest NRR activity while suppressing the competitive hydrogen evolution reaction, with a low limiting potential of −0.62 V via associative distal path. This work suggests new opportunities for driving NH3 production by carbon-based single-atom electrocatalysts under ambient conditions. 相似文献
166.
Li Zhao Qiangjun Ling Xiong Liu Chaodong Hang Qiuxia Zhao Fangfei Liu Haibin Gu 《应用有机金属化学》2018,32(2)
Owing to their unique broken symmetry, amphiphilic Janus dendrimers and dendons provide fascinating properties for material, biological, pharmaceutical and biomedical applications. The integration of various organometallic moieties into these macromolecules will further offer the opportunity to form complex and intelligent architectures and materials. Here, we report a novel, simple and multifunctional Janus dendron containing redox‐reversible hydrophobic ferrocene (Fc) unit, complexing‐effective 1,2,3‐triazole ligand and biocompatible hydrophilic triethylene glycol termini. Silver and gold nanoparticles were firstly successfully prepared by using the Janus dendron as the reducing agent of Au(III) and Ag(I), and the stabilizer of the corresponding nanoparticles. The redox response of the Fc moiety was then employed to trigger the release of model drug, rhodamine B, encapsulated in supramolecular micelles formed by the self‐assembly of the Janus dendron. Finally, the precise and excellent metal‐complexing ability of the triazole group in this dendron was fully utilized to stabilize a water‐soluble Cu(I) catalyst, forming supramolecular nanoreactors for the catalysis of the copper(I)‐catalyzed azide alkyne cycloaddition click reaction in only water. The multifunctional characteristics of this dendron highlight the potential for organometallic Janus dendrimers and dendrons in the fields of functional materials and nanomedicines. 相似文献
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Manqi Ruan Hang Zhao Gang Li Chengdong Fu Zhigang Wang Xinchou Lou Dan Yu Vincent Boudry Henri Videau Vladislav Balagura Jean-Claude Brient Peizhu Lai Chia-Ming Kuo Bo Liu Fenfen An Chunhui Chen Soeren Prell Bo Li Imad Laketineh 《The European Physical Journal C - Particles and Fields》2018,78(5):426
After the Higgs discovery, precise measurements of the Higgs properties and the electroweak observables become vital for the experimental particle physics. A powerful Higgs/Z factory, the Circular Electron Positron Collider (CEPC) is proposed. The Particle Flow oriented detector design is proposed to the CEPC and a Particle Flow algorithm, Arbor is optimized accordingly. We summarize the physics object reconstruction performance of the Particle Flow oriented detector design with Arbor algorithm and conclude that this combination fulfills the physics requirement of CEPC. 相似文献
169.
右心室分割对肺动脉高压等疾病的心功能分析具有重要的临床意义.然而,右心室心肌薄、易变且不规则,其传统的医学图像分割方法仍然未能取得突破性进展.本文提出基于COLLATE(Consensus Level,Labeler Accuracy and Truth Estimation)的多图谱分割方法,首先以归一化互信息为相似测度对目标图像和图谱集进行B样条配准以获取粗分割结果;然后利用COLLATE对粗分割结果进行融合;最后采用基于形状约束的区域生长算法修正出现错误的数据.10例临床心脏磁共振短轴电影图像被用于算法验证.本文还将使用基于COLLATE的多图谱分割方法得到的结果与深度学习算法及手动分割进行了比较.结果显示与深度学习算法比较,使用本文算法得到的射血分数(Ejection Fraction,EF)与手动分割更加一致和相关,表明该算法的分割结果有望辅助临床心脏功能诊断. 相似文献
170.