概率语言多属性群决策方法及其在新型智慧城市市民获得感评价中的应用

针对公众参与的语言信息多属性群决策问题，研究了考虑参与者满意度的概率语言多属性群决策方法。首先，根据参与者的语言评价信息确定并规范化概率语言决策矩阵。然后，对大群体进行共识分析，由最大化参与者群体的满意度构建线性规划模型，确定参与者群组的权重；构造正、负理想方案的评价向量，构建多目标规划模型，用拉格朗日乘子法求解属性权重；定义各方案的加权贴近度，并以此对方案进行排序和优选。最后，通过新型智慧城市市民获得感评价案例验证了模型的可行性和有效性。     

基于耦合声场建模的膨胀腔消声器声学性能分析及试验

针对圆柱形膨胀腔消声器三维建模及声学性能分析问题, 提出一种基于切比雪夫变分原理的耦合声场建模方法, 建立三维圆柱形膨胀腔消声器理论模型并搭建试验台架, 传递损失试验结果验证了理论模型的准确性. 将膨胀腔消声器内部声场分解为多个子声场, 基于子声场间压力与质点振速连续性条件, 推导声场耦合变分公式, 构建子声场拉格朗日泛函. 将子声场声压函数展开为切比雪夫-傅里叶级数形式, 通过瑞利-里兹法求解膨胀腔消声器频率、声压响应及传递损失. 计算并对比分析扩张比、扩张腔长度、进出口管偏置对膨胀腔消声器消声性能的影响. 结果表明: 扩张比增大会有效提高消声器在低频段的消声性能, 进出口管的偏置对消声器消声性能影响很小.     

Unconditionally optimal convergence of an energy-conserving and linearly implicit scheme for nonlinear wave equations

In this paper, we present and analyze an energy-conserving and linearly implicit scheme for solving the nonlinear wave equations. Optimal error estimates in time and superconvergent error estimates in space are established without certain time-step restrictions. The key is to estimate directly the solution bounds in the H²-norm for both the nonlinear wave equation and the corresponding fully discrete scheme, while the previous investigations rely on the temporal-spatial error splitting approach. Numerical examples are presented to confirm energy-conserving properties, unconditional convergence and optimal error estimates, respectively, of the proposed fully discrete schemes.

     

改性多孔CO2吸附剂的研究进展

由温室效应带来的全球变暖等一系列环境危害已受到越来越多的关注,CO2是对温室效应贡献最大的气体且用途广泛,因此,其控制减排及再利用尤为重要.综述了近年被广泛研究的CO2多孔吸附剂的发展状况,详尽阐述了沸石、多孔炭、有机金属骨架(MOFs)和多种介孔吸附剂的优缺点及其改性方法,同时比较了这几种多孔吸附剂改性前后的特性及其对CO2的吸附效果.并且展望了CO2吸附剂的发展前景,为新型高效CO2吸附剂的研发提供了参考.     

Thermal analysis of beamline heat load components due to increased power delivery from EAST neutral beam injector

Journal of Thermal Analysis and Calorimetry - According to EAST’s experimental plan, the long-pulse and high-power operation of neutral beam injector is the requirement for EAST. In this...     

Redox-Active Two-Dimensional Covalent Organic Frameworks (COFs) for Selective Reductive Separation of Valence-Variable,Redox-Sensitive and Long-Lived Radionuclides

We report the first example of 2D covalent organic framework nanosheets (Redox-COF1) for the selective reduction and in situ loading of valence-variable, redox-sensitive and long-lived radionuclides (abbreviated as VRL nuclides). Compared with sorbents based on chemical adsorption and physical adsorption, the redox adsorption mechanism of Redox-COF1 can effectively reduce the impact of functional group protonation under the usual high-acidity conditions in chemisorption, and raise the adsorption efficiency from the monotonous capture by pores in physisorption. The adsorption selectivity for UO₂²⁺ reaches up to unprecedented ca. 97 % at pH 3, more than for any analogous adsorbing material.     

Quantum State Sharing Under Noisy Environment

International Journal of Theoretical Physics - Quantum state sharing (QSS) plays significant role in transmitting quantum secret information. However, in practical quantum communication situation,...     

硫源和六元瓜环对硫化镉性质的影响

以硫代硫酸钠和硫脲为硫源,氯化镉为镉源,六元瓜环(Q[6])为修饰剂,采用水热法制备Q[6]/CdS复合光催化剂.利用傅里叶变换红外光谱、X射线粉末衍射和扫描电子显微镜对产物进行结构和形貌表征,考察Q[6]和硫源对产物结构和性能的影响.结果表明,硫源对产物形貌和结构都有影响,Q[6]对硫化镉光催化性能有增强作用,15 mg Q[6]/CdS能使50 mL,6 mg/L的次甲基蓝溶液反应200 min时的降解率达到93.0;以上.     

A Tri-state Fluorescent Switch with “Gated” Solid-state Photochromism Induced by an External Force

Mr. Chen Qian, Dr. Zhimin Ma, Mr. Jianwei Liu, Mrs. Xue Zhang, Prof. Shitao Wang and Prof. Zhiyong Ma. In this article, we report a newly designed molecule composed of a dihydroazulene (DHA) group and a phenothiazine (PTZ) moiety, which achieves aggregation-induced emission enhancement (AIEE), mechanochromism and “gated” solid-state photochromism upon stimulation by an external force. Grinding loosens intermolecular interactions in the crystal and causes a red-shift of fluorescence from 570 nm to 600 nm. Meanwhile, the ring-opening reaction of DHA unit is activated by grinding and a remarkable photochromism could be observed from the grinded powder. The reddish emission of the grinded powder peaked at 600 nm weakened gradually and finally became dark, and a new absorption band at 470 nm emerged in the absorption spectra. Time-dependent density functional theory (TD-DFT) calculation results reveal that the intramolecular intramolecular charge-transfer (ICT) process is replaced by a locally excited (LE) emission on the DHA group, which leads to the quenching of fluorescence. Its impressive photochromic property inspired us to a simple but effective way to develop an encryption system which can let the correct information be displayed upon external stimulation.     

一道2020年全国大学生数学竞赛题的多种推广

对最近一道2020年全国大学生数学竞赛题从多个角度进行推广,由此不但丰富了课堂例题,拓展了教学内容,而且激发了同学们的学习热情,促进了同学们创新思维能力的提升.