狭缝式高速摄影机胶片的计算机判读

根据狭缝摄影机胶片的成象原理,运用数字图象处理技术,对狭缝式高速摄影机胶片判读工作的计算机化进行研究.应用结果表明,该技术先进实用,极大地提高了判读的精度和效率,将是这种胶片判读技术的发展方向.     

导电性聚西佛碱的研究：Ⅰ含硫聚西佛碱的合成,性能及表征

采用对氯苯甲醛和联苯二胺为原料,合成了4,4′-二氯代苄叉联苯胺,发现该化合物具有热致液晶性。利用所合成的二氯代化合物与硫化钠在醋酸锂催化下缩取得得到了含硫聚西佛碱探讨了高分子量含硫聚西佛碱的合成方法。测出该含硫聚西佛碱具有3.4×10~(-11)S/cm本征导电率。使用红外光谱、元素分析等方法表征了所合成的聚合物。     

Range-Renewal Processes: SLLNs and Power Laws*

Given n samples(viewed as an n-tuple) of a γ-regular discrete distribution π,in this article the authors concern with the weighted and unweighted graphs induced by the n samples. They first prove a series of SLLN results(of Dvoretzky-Erd¨os’ type). Then they show that the vertex weights of the graphs under investigation obey asymptotically power law distributions with exponent 1 + γ. They also give a conjecture that the degrees of unweighted graphs would exhibit asymptotically power law distribu...     

Polyacrylonitrile/Aminated Polymeric Nanosphere Nanofibers as Efficient Adsorbents for Cr(VI) Removal

In this work, polyacrylonitrile/aminated polymeric nanosphere (PAN/APN) nanofibers were prepared by electrospinning of monodispersed aminated polymeric nanospheres (APNs) for removal of Cr(VI) from aqueous solution. Characterization results showed that obtained PAN/APNs possessed nitrogen functionalization. Furthermore, the adsorption application results indicated that PAN/APN nanofibers exhibited a high adsorption capacity of 556 mg/g at 298 K for Cr(VI) removal. The kinetic data showed that the adsorption process fits the pseudo-second order. A thermodynamic study revealed that the adsorption of Cr(VI) was spontaneous and endothermic. The coexisting ions Na⁺, Ca²⁺, K⁺, Cl⁻, NO₃⁻ and PO₄³⁻ had little influence on Cr(VI) adsorption, while SO₄²⁻ in solution dramatically decreased the removal performance. In the investigation of the removal mechanism, relative results indicated that the adsorption behavior possibly involved electrostatic adsorption, redox reaction and chelation. PAN/APN nanofibers can detoxify Cr(VI) to Cr(III) and subsequently chelate Cr(III) on its surface. The unique structure and nitrogen functionalization of PAN/APN nanofibers make them novel and prospective candidates in heavy metal removal.     

4-苯乙炔苯酐封端聚酰亚胺树脂的合成与性能研究

使用3,3′,4,4′-二苯醚四酸二酐(ODPA)、3,3′,4,4′-联苯四酸二酐(BPDA)、1,3-双(4-氨基苯氧基)苯(1,3,4-APB)、3,4′-二氨基二苯醚(3,4′-ODA)和反应性封端剂4-苯乙炔苯酐(4-PEPA)合成了设计分子量为5000的系列苯乙炔基封端的聚酰亚胺低聚物,并使用XRD、DSC、TGA、FT-IR、DMA和流变仪等对低聚物的化学结构、热性能和熔体性能,固化后树脂的热性能和力学性能进行了测试.研究结果表明基于ODPA的低聚物具有低的熔体粘度和良好的熔体粘度稳定性,固化后的树脂具有很高的热失重温度,较高的玻璃化转变温度以及良好的力学性能尤其是高的断裂伸长率(>10%);基于BPDA的低聚物具有一定的结晶性,其结晶熔融温度与苯乙炔基固化交联温度相近,影响了材料的成型工艺性能.     

基于白噪声模型的结构振动响应估计及控制优化

为研究平稳随机振动下的结构响应估计与结构控制,首先对理想白噪声、限宽白噪声、连续限宽白噪声这三种白噪声模型的统计特征进行研究,对理想白噪声与限宽白噪声模型的时频特征进行了详细的理论分析,推导了连续限宽白噪声模型的自相关函数,并结合数值仿真对其信号频谱特征进行了验证与说明;其次,以三层剪切框架为例,详细推导了利用李雅普诺夫方程与理想白噪声模型预测结构振动信号的方差特性的过程;最后,针对广州新电视塔,利用随机地震金井清模型进行结构控制优化研究与分析,提出了同时考虑调频质量阻尼器频率与阻尼的结构控制优化设计方法.     

分光计测定光栅常数

针对分光计测定光栅常数实验中入射光线偏离光栅法线的情形,提出了计算光栅常数的一个近似表达式。在不增加额外测量的前提下,使实验结果更接近于实际值。     

Uncertain multiobjective traveling salesman problem

Traveling salesman problem is a fundamental combinatorial optimization model studied in the operations research community for nearly half a century, yet there is surprisingly little literature that addresses uncertainty and multiple objectives in it. A novel TSP variation, called uncertain multiobjective TSP (UMTSP) with uncertain variables on the arc, is proposed in this paper on the basis of uncertainty theory, and a new solution approach named uncertain approach is applied to obtain Pareto efficient route in UMTSP. Considering the uncertain and combinatorial nature of UMTSP, a new ABC algorithm inserted with reverse operator, crossover operator and mutation operator is designed to this problem, which outperforms other algorithms through the performance comparison on three benchmark TSPs. Finally, a new benchmark UMTSP case study is presented to illustrate the construction and solution of UMTSP, which shows that the optimal route in deterministic TSP can be a poor route in UMTSP.     

Large-Scale Synthesis of MOF-Derived Superporous Carbon Aerogels with Extraordinary Adsorption Capacity for Organic Solvents

Carbon aerogels (CAs) with 3D interconnected networks hold promise for application in areas such as pollutant treatment, energy storage, and electrocatalysis. In spite of this, it remains challenging to synthesize high-performance CAs on a large scale in a simple and sustainable manner. We report an eco-friendly method for the scalable synthesis of ultralight and superporous CAs by using cheap and widely available agarose (AG) biomass as the carbon precursor. Zeolitic imidazolate framework-8 (ZIF-8) with high porosity is introduced into the AG aerogels to increase the specific surface area and enable heteroatom doping. After pyrolysis under inert atmosphere, the ZIF-8/AG-derived nitrogen-doped CAs show a highly interconnected porous mazelike structure with a low density of 24 mg cm⁻³, a high specific surface area of 516 m² g⁻¹, and a large pore volume of 0.58 cm⁻³ g⁻¹. The resulting CAs exhibit significant potential for application in the adsorption of organic pollutants.     

Metal–Organic Frameworks as Metal Ion Precursors for the Synthesis of Nanocomposites for Lithium‐Ion Batteries

Metal–organic frameworks (MOFs) are promising materials with fascinating properties. Their widespread applications are sometimes hindered by the intrinsic instability of frameworks. However, this instability of MOFs can also be exploited for useful purposes. Herein, we report the use of MOFs as metal ion precursors for constructing functional nanocomposites by utilizing the instability of MOFs. The heterogeneous growth process of nanostructures on substrates involves the release of metal ions, nucleation on substrates, and formation of a covering structure. Specifically, the synthesized CoS with carbon nanotubes as substrates display enhanced performance in a lithium‐ion battery. Such strategy not only presents a new way for exploiting the instability of MOFs but also supplies a prospect for designing versatile functional nanocomposites.