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101.
102.
Hua-Qing Yin Kui Tan Stephanie Jensen Simon J. Teat Saif Ullah Xiuze Hei Ever Velasco Kolade Oyekan Noah Meyer Xin-Yao Wang Timo Thonhauser Xue-Bo Yin Jing Li 《Chemical science》2021,12(42):14189
Fluorosis has been regarded as a worldwide disease that seriously diminishes the quality of life through skeletal embrittlement and hepatic damage. Effective detection and removal of fluorinated chemical species such as fluoride ions (F−) and perfluorooctanoic acid (PFOA) from drinking water are of great importance for the sake of human health. Aiming to develop water-stable, highly selective and sensitive fluorine sensors, we have designed a new luminescent MOF In(tcpp) using a chromophore ligand 2,3,5,6-tetrakis(4-carboxyphenyl)pyrazine (H4tcpp). In(tcpp) exhibits high sensitivity and selectivity for turn-on detection of F− and turn-off detection of PFOA with a detection limit of 1.3 μg L−1 and 19 μg L−1, respectively. In(tcpp) also shows high recyclability and can be reused multiple times for F− detection. The mechanisms of interaction between In(tcpp) and the analytes are investigated by several experiments and DFT calculations. These studies reveal insightful information concerning the nature of F− and PFOA binding within the MOF structure. In addition, In(tcpp) also acts as an efficient adsorbent for the removal of F− (36.7 mg g−1) and PFOA (980.0 mg g−1). It is the first material that is not only capable of switchable sensing of F− and PFOA but also competent for removing the pollutants via different functional groups.A robust In-MOF, In(tcpp), demonstrates sensitive detection of the fluorinated chemical species F− and PFOA via distinctly different luminescence signal change, and effective adsorption and removal of both species from aqueous solution. 相似文献
103.
Chifei Wu Tada‐Aki Yamagishi Yoshiaki Nakamoto Shin‐Ichiro Ishida Koh‐Hei Nitta Saburo Kubota 《Journal of Polymer Science.Polymer Physics》2000,38(10):1341-1347
The dynamic mechanical properties of an organic hybrid consisting of chlorinated polyethylene (CPE) and N,N‐dicyclohexyl‐2‐benzothiazolyl sulfenamide (DZ) were investigated. All the CPE/DZ hybrids showed a single loss tangent (tan δ) peak in the mechanical spectra. The peak area under the tan δ/temperature curves around the mechanical loss peak was examined to characterize the damping properties of the CPE/DZ hybrids. We found that there exists a bending point in the relation between the glass‐transition temperature (Tg) and DZ content and that the value of Tg is saturated in the higher DZ contents, suggesting that excess DZ molecules show self‐aggregation and are reorganized. © 2000 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 38: 1341–1347, 2000 相似文献
104.
Jinpei Hei Liwei Su Siyuan Chen Weijun Ye Jing Zhan Lianbang Wang Yunfang Gao Hongxia Wang Yuanhao Wang 《Particle & Particle Systems Characterization》2020,37(1):1900344
Reasonable design and delicate control of microstructures are critical to achieve high energy density of active materials for pseudocapacitors that seriously depend on usable reaction interface. This work shows the effect of ultrasmall particle size on enhancing utilization and rate performance of active materials. Three types of NiO nanocrystals with different sizes of 3.36, 6.24, and 7.18 nm in average diameter are uniformly distributed on mesoporous carbon nanosheets derived from corn straw piths. The nanosheets with 3.36 nm NiO particles present an extremely high NiO utilization of 93.4% (2404 F g−1 at 0.5 A g−1), which is 2–2.5-fold higher than materials with large sizes (6.24 and 7.18 nm). This enhancement is ascribed to more complete conversion and higher ionic/electronic conductivity from a preferable surface/bulk ratio of NiO. By coupling with commercial activated carbon, the asymmetric supercapacitors present high energy and power densities (28.53 Wh kg−1 at 375 W kg−1), with 78.3% capacitance retention after 10 000 cycles at 10 A g−1. 相似文献
105.
Liwei Su Yizhe Zhao Zhemin Li Jinpei Hei Huan Chen Lianbang Wang Yuanhao Wang Manman Ren 《Particle & Particle Systems Characterization》2020,37(7):2000113
As anodes for lithium-ion batteries, CoCO3 has a much higher specific capacity than graphite and can meet the urgent demands of electric vehicles and portable electronics. However, reported CoCO3 anodes are of micrometer-sized morphology (0.4–10 µm) that severely limits long-term and rate performances (in particular >2.0 A g−1) due to intrinsically low conductivity and high volume expansion. Mesoporous materials have uniform open mesopores to offer sufficient solid/electrolyte contact, rapid Li+ transport, and large pore volume. However, it is still challenging to prepare uniform mesoporous CoCO3 nanostructures. This work reports a urea–NH4HCO3–ethylene glycol (EG) solvothermal system to fabricate uniform mesoporous CoCO3 nanospindles and concurrently composite with multilayered graphite nanosheets. The obtained mesoporous CoCO3 has a specific surface area of 143.7 m2 g−1, 12.4 times that of commercial CoCO3. The preparation mechanism is studied in-depth, where urea, NH4HCO3, EG, and crystal water play essential and respective roles. The synergistic effect of the mesopore and graphite nanosheets facilitates long-term cycling stability (1465 mAh g−1 after 450 cycles at 200 mA g−1 with 101.1% capacity retention) and high-rate performance (1033 mAh g−1 at 2.0 A g−1). The essential roles of mesopores and graphite nanosheets in boosting the kinetic change are investigated. 相似文献
106.
基于邻苯二甲酸氢铊(TAP)弯晶和软X射线分幅相机建立了一套4通道的时空分辨弯晶摄谱仪,测谱范围1 500~2 300 eV,时间分辨约2 ns。分析了谱仪各环节的信号传递和转换过程对系统谱响应的影响。利用该谱仪在“强光一号”加速器(约1.5 MA, 80~100 ns)Al丝阵Z箍缩实验中获得了时间分辨及时间积分的Al等离子体K层辐射谱,记录到了类H、类He离子主要共振线及类Li、类He离子双电子复合伴线。将摄谱结果与分能区X射线图像进行了比较。时间分辨的发射谱相对强度与积分结果有明显不同,反映了等离子体在5~10 ns时间尺度上的电子温度和离子布居变化。 相似文献
107.
108.
Let \({\{\varphi_n(z)\}_{n\ge0}}\) be a sequence of inner functions satisfying that \({\zeta_n(z):=\varphi_n(z)/\varphi_{n+1}(z)\in H^\infty(z)}\) for every n ≥ 0 and \({\{\varphi_n(z)\}_{n\ge0}}\) have no nonconstant common inner divisors. Associated with it, we have a Rudin type invariant subspace \({\mathcal{M}}\) of \({H^2(\mathbb{D}^2)}\) . We write \({\mathcal{N}= H^2(\mathbb{D}^2)\ominus\mathcal{M}}\) . If \({\{\zeta_n(z)\}_{n\ge0}}\) ia a mutually prime sequence, then we shall prove that \({rank_{\{T^\ast_z,T^\ast_w\}} \mathcal{N}=1}\) and \({rank_{\{\mathcal{F}^\ast_z\}}(\mathcal{M}\ominus w\mathcal{M})=1}\) , where \({\mathcal{F}_z}\) is the fringe operator on \({\mathcal{M}\ominus w\mathcal{M}}\) . 相似文献
109.
P. Rinn H. Heißelmann M. Wächter J. Peinke 《The European Physical Journal B - Condensed Matter and Complex Systems》2013,86(1):1-5
We are going to apply dissipative energy method, considered as perturbation method, in order to investigate the effects of electron-optical phonon coupling on the electronic transport of armchair single wall carbon nanotubes. This method almost deals with the modeling of the behavior of electrons near ballistic regime. The results of calculations indicate that this model can be applied in estimating the current and the differential conductance of the armchair single-wall carbon nanotubes at low bias; however the perturbation method fails to reproduce the current and differential conductance at high voltages. Furthermore, this approach suggests a method that the observation of phonon energy modes involved in electron-phonon coupling becomes possible experimentally at low temperature. 相似文献
110.