排序方式: 共有66条查询结果,搜索用时 46 毫秒
31.
A.V. Morozkin Jinlei Yao Y. Mozharivskyj O. Isnard 《Journal of magnetism and magnetic materials》2012
We present a neutron powder diffraction investigation of the magnetic structure of La3NiGe2-type Tb3NiGe2 and Mn5Si3-type Tb5NixGe3−x (x=0, 0.3) compounds. It is found that below∼135 K Tb3NiGe2 exhibits a commensurate b-collinear ferrimagnetic ordering with C2h′={1, mz, 1′×2z, 1′×1?} magnetic point group. The Mn5Si3-type Tb5Ge3 and Tb5Ni0.3Ge2.7 compounds are found to present a flat spiral type antiferromagnetic ordering at 85 and ≥89 K, respectively. The Ni for Ge substitution is found to decrease the flat spiral ordered magnetic unit cell from a×a×40c of Tb5Ge3 (below 40 K) down to a×a×5c for Tb5Ni0.3Ge2.7 (below ∼10 K). 相似文献
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使用Dy(NO3)3·6H2O与席夫碱配体2-(((2-羟基-3-甲氧基苄基)亚氨基)甲基)-4-甲氧基苯酚(H2L)和2个辅助配体PhCO2H和2-NO2-PhCO2H在乙醇中反应,得到2例Dy4配合物[Dy4(L)4(PhCO2)2(NO3)2(EtOH)2](1)和[Dy4(L)4(2-NO2-PhCO2)2(NO3)2(EtOH)2](2)。单晶X射线衍射解析表明配合物1和2均由Dy2基本单元构建,形成中心对称的四核线性链状结构。配合物1和2中Dy2单元中的一个Dy(Ⅲ)离子呈现七配位几何构型,另一个Dy(Ⅲ)离子呈现八配位几何构型。2例配合物均为单分子磁体,其能垒分别为110和108 K。通过理论计算对1和2的磁性能进行了分析。 相似文献
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Jinlei Yang Pengchao Liu Xiao He Junjun Hou Yaping Feng Zhiwei Huang Lian Yu Lianshan Li Zhiyong Tang 《Angewandte Chemie (International ed. in English)》2020,59(15):6244-6248
Precise control of ion transport is a fundamental characteristic for the sustainability of life. It remains a great challenge to develop practical and high‐performance artificial ion‐transport system that can allow active transport of ions (protons) in an all solid‐state nanoporous material. Herein, we develop a Janus microporous membrane by combining reduced graphene oxide (rGO) and conjugated microporous polymer (CMP) for controllable photodriven ion transport. Upon light illumination, a net ionic current is generated from the CMP to the rGO side of the membrane, indicating that the rGO/CMP Janus membrane can realize photodriven directional and anti‐gradient ion transport. Analogously to the p‐n junction in photovoltaic devices, light is firstly converted into separated charges to trigger a transmembrane potential, which subsequently drives directional ion movement. For the first time, this method enables integration of a photovoltaic effect with an ionic field to drive active ion transport. With the advantages of scaled up production and easy fabrication, the concept of photovoltaic ion transport based on Janus microporous membrane may find wide application in energy storage and conversion, photodriven ion‐sieving, and water treatment. 相似文献
34.
Qian J Wang L Gu W Liu X Tian J Yan S 《Dalton transactions (Cambridge, England : 2003)》2011,40(20):5617-5624
Two water-soluble zinc complexes, [Zn(L)Cl(2)] (1) and [Zn(2)(L)(2)(μ-C(2)O(4))(H(2)O)(2)]·(ClO(4))(2)·CH(3)OH (2) (L = N,N-bis(2-pyridylmethyl)methylamine), were prepared to serve as nuclease mimics. The complexes were characterized by X-ray, IR and UV-vis spectroscopy as well as ESI-MS. The electrospray mass spectrum of 2 in solution indicates that dinuclear ion [Zn(2)(L)(2)(μ-C(2)O(4))(ClO(4))](+) (3) is the active species. UV-Vis absorption and fluorescence spectroscopy studies show that the complexes partially intercalate to CT-DNA. In the absence of reducing agent, supercoiled plasmid DNA cleavage by the complexes 1 and 3 was performed and the hydrolytic mechanism was demonstrated by adding standard radical scavengers. 相似文献
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Yanyan Dong Yanfang Lu Changyu Shen Jinlei Chu Xin Zou Chuan Zhong Xinyong Dong 《Optik》2013,124(24):6737-6739
A novel bending sensor based on a long period fiber grating (LPG) is presented. A LPG was glued into a V-shaped groove, which lies on the lower surface of a meniscus shaped beam. It is found that the transmission optical power of the LPG changed linearly with the variation of the bending of the beam. The bending applied on the beam can be measured by detecting the intensity variation of the LPG's resonant dip wavelength. Under a relative large bending measured range from 0 to 7.5 m?1, the sensitivity of 3.003 dB m?1 and curvature resolution of 0.001 m?1 have been achieved for the proposed bending sensor. 相似文献
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研究了润滑油密度与黏度的关系,并提出了一个由密度求黏度的新黏压关系式.以Dowson-Higginson密度公式为媒介,新公式只改变一个常数可退化为Barus黏压关系,而改变两个常数可退化为Doolittle自由体积黏压关系.用Dowson-Higginson密压关系消去密度,新公式具有与Roelands黏压关系相同的结构,但对应常数各不相同.以squalane油为例,给出了由实验数据确定新公式中两个待定常数的简单方法,而如此确定下来的新公式可以与全部实验数据吻合良好.应用新公式计算黏度并以squalane油品为润滑剂,可顺利求得等温椭圆接触弹性流体动力润滑的数值解,说明新公式具有良好的适应性. 相似文献
38.
Jinlei Yao Carly N. Kline Hao Gu Mi Yan Jennifer A. Aitken 《Journal of solid state chemistry》2009,182(9):2579-2586
Mn-doped CuInSe2 compounds (CuIn1−xMnxSe2, x=0.0125–0.20 and Cu1−yIn1−yMn2ySe2, 2y=0.0125–0.60) were synthesized by high-temperature solid-state reactions. Single phase materials with chalcopyrite structure persist up to 0.10 and 0.20 doping for CuIn1−xMnxSe2 and Cu1−yIn1−yMn2ySe2, respectively. The chalcopyrite and sphalerite phases co-exist in the Cu1−yIn1−yMn2ySe2 system for 2y=0.25–0.50. Attempts to introduce greater manganese content, x=0.15–0.20 for CuIn1−xMnxSe2 and 2y=0.60 for Cu1−yIn1−yMn2ySe2, result in partial phase segregation. For the single-phase samples, the lattice parameters of both systems increase linearly with manganese concentration and thus follow Vegard's law. The temperature of the chalcopyrite–sphalerite phase transition is decreased by manganese substitution for all single-phase samples. The bandgap of the materials remains around 0.9 eV. Additionally, the Mn-doped CuInSe2 compounds display paramagnetic behavior, whereas pure CuInSe2 is diamagnetic at 5–300 K. All the CuIn1−xMnxSe2 and Cu1−yIn1−yMn2ySe2 compounds with chalcopyrite structure show antiferromagnetic coupling and measured effective magnetic moments up to 5.8 μB/Mn. 相似文献
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一个基于恢复时间的新剪稀模型及其对聚合油PAO 650流变特性的模拟 总被引:1,自引:1,他引:0
用球-杆比拟流体层上的分子,通过分析两流体层上球-杆的接触、通过和恢复的过程,基于球-杆恢复到原状态的时间,建立了一个新剪稀模型.该模型虽然在形式上与Carreau模型有相似之处,但其公式仅含有两个流变参数,且是经由严格的理论推导得到的.通过与Carreau模型得到的广义黏度曲线的比较,确定了新流变公式的待定参数.在点接触流变热弹流润滑的数学模型中使用新流变公式,数值模拟了大黏度聚合油PAO 650的流变特性,并与该油在文献中的试验曲线进行了比对.结果表明新流变模型能够较好地模拟大黏度聚合油的流变特性,从而证实了其正确性.进一步,使用新公式计算得到了更多工况下的流变特性曲线,光滑的、合理的曲线分布说明新流变模型具有广泛的适用性. 相似文献
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