3,4-二(3-苯氧基-4-氟苯基)-2,5-二苯基苯基接枝聚硅氧烷气相色谱固定相的合成与表征（英文）

合成了一种耐高温的3,4-二(3-苯氧基-4-氟苯基)-2,5-二苯基苯基接枝聚硅氧烷(DPFP)固定相,使用静态涂渍法将其涂渍到毛细管柱内壁上,制成气相色谱柱。分离裂解乙烯的色谱图显示DPFP固定相在360℃时仍具有良好的分离能力。DPFP固定相的柱效为3 324块/米(保留因子(k)4.24,萘,0.25 mm i.d.)。麦克雷诺常数计算结果显示DPFP固定相属中等极性。溶剂化参数模型结果显示DPFP固定相与溶质之间的主要作用力为偶极-诱导偶极作用力、氢键碱性作用力。Grob试剂分离结果显示DPFP色谱柱具有良好的选择性与惰性。另外,芳香族同分异构体、苯取代物、多环芳烃、脂肪酸酯及脂肪醇都得到了良好的分离,表明DPFP固定相在应用方面有巨大的潜力。     

银负载量对网状TiO_2柔性薄膜电极储锂性能的影响

采用水热法结合银镜反应制备出一系列不同Ag负载量(2.2%、4.0%、6.4%,w/w)改性的3D纳米网状结构Ag@Ti O2薄膜电极。利用电感耦合等离子体技术(ICP)、X射线衍射(XRD)、扫描电镜(SEM)、透射电镜(TEM)和X射线能谱(EDX)等表征手段测试所合成材料的形貌及成分,实验结果表明Ag纳米颗粒可以成功沉积在Ti O2纳米线表面。电化学测试数据则表明,4.0%(w/w)负载量的Ag@Ti O2相比于未改性和其他负载量的Ti O2纳米线具有更好的倍率性能和更稳定的可逆容量。在50,100,200,400,800和1 200 m A·g~(-1)的电流密度条件下,该改性电极的放电容量可分别达到261.4,253.7,239.5,216.5,193.1和185.1 m Ah·g~(-1),在200 m A·g~(-1)下循环80次后容量保持率仍能达到99.8%。     

Study of structural parameters on the adsorption selectivity of a molecularly imprinted polymer

This work was focused on the influence of match degree of structure parameters i.e. molecular size, volume and polarity (denoted as R_d, V_d and P_d) between imprinted cavities in Qu-MIP and Xn on the adsorption selectivity. The results presented that the influence of R_d on the adsorption selectivity was the largest and the most regular, while the influence of P_d was the smallest and the most irregular. Besides, the influence degree of V_d was decreased in general with the increase of R_d. However, as R_d was in the threshold of [0.99, 1.02], V_d would rise to the major influence factor. Furthermore, utilizing data obtained from experiment, the influence authority of R_d, V_d and P_d on the adsorption selectivity was calculated theoretically through multiple linear regression and principal component analysis of IBM SPSS Statistics 20, and results showed the authority order was R_d, V_d and P_d at any circumstance despite the value was different, which was in accordance with the result we directly inducted from the experiment.     

关于泰勒公式及其应用的再认识

本文首先给出了在欧氏空间下泰勒公式及余项的不同表示,之后把泰勒公式进一步推广到巴拿赫空间,给出了多维与无限维空间上算子形式的泰勒公式;最后,阐述了泰勒公式在数学学科和其它学科广泛而深刻的应用,从而揭示了泰勒公式的核心与灵魂.     

The fourth power mean of the general 2-dimensional Kloostermann sums mod <Emphasis Type="Italic">p</Emphasis>

The main purpose of this paper is using the analytic methods and the properties of Gauss sums to study the computational problem of one kind fourth power mean of the general 2-dimensional Kloostermann sums mod p, and give an exact computational formula for it.     

Novel Bi2MoO6 Nanosheets/Vertical TiO2 Nanorods Arrays Heterojunction with Enhanced Photoelectrochemical Performance under Visible Light Irradiation

Novel Bi₂MoO₆/TiO₂ heterojunction was fabricated by growing Bi₂MoO₆ nanosheets arrays on the vertically aligned TiO₂ nanorods arrays via a two-step solvothermal method. The obtained Bi₂MoO₆/TiO₂ hierarchical heterojunction showed excellent visible light photoelectrochemical performance. Compared with the pure TiO₂ and Bi₂MoO₆, the photocurrent density of the heterojunction was increased 57 and 29 times, respectively. Furthermore, the hydrogen generation rate of the Bi₂MoO₆/TiO₂ for photoelectrocatalytic water-splitting was about 6 times higher than that of the pure Bi₂MoO₆. The improved performance can be attributed to the synergistic effects of enhanced absorption of visible light, increase of migration rate and separation efficiency of photo-induced carriers.     

Effect of furan π-bridge on the photovoltaic performance of D-A copolymers based on bi(alkylthio-thienyl)benzodithiophene and fluorobenzotriazole

The medium band gap donor-acceptor(D-A) copolymer J61 based on bi(alkylthio-thienyl)benzodithiophene as donor unit and fluorobenzotriazole as acceptor unit and thiophene as π-bridge has demonstrated excellent photovoltaic performance as donor material in nonfullerene polymer solar cells(PSCs) with narrow bandgap n-type organic semiconductor ITIC as acceptor.For studying the effect of π-bridges on the photovoltaic performance of the D-A copolymers,here we synthesized a new D-A copolymer J61-F based on the same donor and acceptor units as J61 but with furan π-bridges instead of thiophene.J61-F possesses a deeper the highest occupied molecular orbital(HOMO) level at-5.45 eV in comparison with that(-5.32 eV) of J61.The non-fullerene PSCs based on J61-F:ITIC exhibited a maximum power conversion efficiency(PCE) of 8.24%with a higher open-circuit voltage(V_(oc)) of 0.95 V,which is benefitted from the lower-lying HOMO energy level of J61-F donor material.The results indicate that main chain engineering by changing π-bridges is another effective way to tune the electronic energy levels of the conjugated D-A copolymers for the application as donor materials in non-fullerene PSCs.     

<Emphasis Type="Italic">Tetra</Emphasis>-armed conjugated microporous polymers for gas adsorption and photocatalytic hydrogen evolution

Two novel tetra-armed conjugated microporous polymers with different geometries have been designed and synthesized via Suzuki-Miyaura cross coupling polycondensation. Both polymers are stable in various organic solvents tested and are thermally stable. The pyrene-containing polymer of PrPy with the rigid pyrene unit shows a higher Brunauer-Emmet-Teller specific surface area of 1219 m² g^?1 than the tetraphenylethylene-containing polymer of PrTPE (770 m² g^?1), which leads to a high CO₂ uptake ability of 3.89 mmol g^?1 at 1.13 bar/273 K and a H₂ uptake ability of 1.69 wt% at 1.13 bar/77 K. The photocatalytic hydrogen production experiments revealed that PrPy also shows a better photocatalytic performance than PrTPE due to the higher conjugation degree and planar structure, the broader UV-visible (UV-Vis) absorption, the lower photoluminescence lifetime, and the higher specific surface area.     

Diliberto–Straus algorithm for the uniform approximation by a sum of two algebras

In 1951, Diliberto and Straus [5] proposed a levelling algorithm for the uniform approximation of a bivariate function, defined on a rectangle with sides parallel to the coordinate axes, by sums of univariate functions. In the current paper, we consider the problem of approximation of a continuous function defined on a compact Hausdorff space by a sum of two closed algebras containing constants. Under reasonable assumptions, we show the convergence of the Diliberto–Straus algorithm. For the approximation by sums of univariate functions, it follows that Diliberto–Straus’s original result holds for a large class of compact convex sets.     

Rogue waves in baroclinic flows

We investigate an AB system, which can be used to describe marginally unstable baroclinic wave packets in a geophysical fluid. Using the generalized Darboux transformation, we obtain higher-order rogue wave solutions and analyze rogue wave propagation and interaction. We obtain bright rogue waves with one and two peaks. For the wave packet amplitude and the mean-flow correction resulting from the self-rectification of the nonlinear wave, the positions and values of the wave crests and troughs are expressed in terms of a parameter describing the state of the basic flow, in terms of a parameter responsible for the interaction of the wave packet and the mean flow, and in terms of the group velocity. We show that the interaction of the wave packet and mean flow and also the group velocity affect the propagation and interaction of the amplitude of the wave packet and the self-rectification of the nonlinear wave.