Supramolecularly assembled water layers stabilized by sebacic anions in complexes of Zn(II) and Co(II)

Two three-dimensional supramolecular water architectures, [Zn(phen)₃]₂·[Zn(C₁₀H₁₆O₄)·(H₂O)₃]·(C₁₀H₁₆O₄)₂·20H₂O (1) and [Co(phen)₃]₂·[Co(H₂O)₆]·(C₁₀H₁₆O₄)₃·30H₂O (2) [phen = 1,10-Phenanthroline, C₁₀H₁₆O₄ = sebacic dianion], have been synthesized and characterized by IR, elemental analysis, thermogravimetric analysis, and single-crystal X-ray diffractions. The two structures both contain extensive hydrogen bonding between water molecules as well as between water molecules and sebacic anions. The water molecules and sebacic acid O atoms assembled 2D supramolecular corrugated sheets with different morphology in the two complexes.     

Orbit determination for Chang’E-2 lunar probe and evaluation of lunar gravity models

The Unified S-Band (USB) ranging/Doppler system and the Very Long Baseline Interferometry (VLBI) system as the ground tracking system jointly supported the lunar orbit capture of both Chang’E-2 (CE-2) and Chang’E-1 (CE-1) missions. The tracking system is also responsible for providing precise orbits for scientific data processing. New VLBI equipment and data processing strategies have been proposed based on CE-1 experiences and implemented for CE-2. In this work the role VLBI tracking data played was reassessed through precision orbit determination (POD) experiments for CE-2. Significant improvement in terms of both VLBI delay and delay rate data accuracy was achieved with the noise level of X-band band-width synthesis delay data reaching 0.2–0.3 ns. Short-arc orbit determination experiments showed that the combination of only 15 min’s range and VLBI data was able to improve the accuracy of 3 h’s orbit using range data only by a 1–1.5 order of magnitude, confirming a similar conclusion for CE-1. Moreover, because of the accuracy improvement, VLBI data was able to contribute to CE-2’s long-arc POD especially in the along-track and orbital normal directions. Orbital accuracy was assessed through the orbital overlapping analysis (2 h arc overlapping for 18 h POD arc). Compared with about 100 m position error of CE-1’s 200 km×200 km lunar orbit, for CE-2’s 100 km×100 km lunar orbit, the position errors were better than 31 and 6 m in the radial direction, and for CE-2’s 15 km×100 km orbit, the position errors were better than 45 and 12 m in the radial direction. In addition, in trying to analyze the Delta Differential One-Way Ranging (ΔDOR) experiments data we concluded that the accuracy of ΔDOR delay was dramatically improved with the noise level better than 0.1 ns and systematic errors better calibrated, and the Short-arc POD tests with ΔDOR data showed excellent results. Although unable to support the development of an independent lunar gravity model, the tracking data of CE-2 provided evaluations of different lunar gravity models through POD. It is found that for the 100 km×100 km lunar orbit, with a degree and order expansion up to 165, JPL’s gravity model LP165P did not show noticeable improvement over Japan’s SGM series models (100×100), but for the 15 km×100 km lunar orbit, a higher degree-order model can significantly improve the orbit accuracy.

     

基于高斯模糊的摔倒自检测算法设计与应用

随着智能设备的普及,如何快速准确地检测、识别人体摔倒已逐渐成为研究的热点。然而现阶段对摔倒动作识别与检测仍然存在很多问题。为此,以智能设备的传感器系统采集的三轴加速度与角加速度为基础,结合经过高斯过滤后形成人体活动的信号幅度向量和陀螺仪信号幅度向量特征曲线与摔倒检测的模糊隶属函数特征模型,提出一种基于模糊的摔倒自检测算法。算法重点针对急速跑动、上下楼梯、手机平抛和自由落体等摔倒检测中的干扰动作进行了分析与区分,经过实验测试表明该算法有较快的反馈速度、较好的区分度以及较低的误判率。     

Total coloring of embedded graphs of maximum degree at least ten

A total k-coloring of a graph G is a coloring of V(G) ∪ E(G) using k colors such that no two adjacent or incident elements receive the same color.The total chromatic number χ〃(G) is the smallest integer k such that G has a total k-coloring.In this paper,it is proved that the total chromatic number of any graph G embedded in a surface Σ of Euler characteristic χ(Σ)≥0 is Δ(G) + 1 if Δ(G)≥10,where Δ(G) denotes the maximum degree of G.     

Selective adsorption and removal ability of pine needle-based activated carbon towards Al(III) from La(III)

Rare earth elements are an important strategic resource. As one of the most valuable member, lanthanum plays a key role in lanthanide. However, trace Al(III) impurity in lanthanum materials can seriously damage the performance of lanthanum materials. In this paper, a nitrogen-containing activated carbon, AC-PN-700, was synthesized using pine needle as raw material and KOH as activator. The AC-PN-700 was characterized by surface area analyzer, elemental analysis and FT-IR. The adsorption and selective ability of AC-PN-700 towards Al(III) were investigated. The BET specific surface area of AC-PN-700 was 596.4 m².g^?1, and the average pore diameter was 2.7?nm. Depend on its large specific surface, well-developed internal pore structure and abundant nitrogen-containing functional groups, the AC-PN-700 possesses strong adsorption affinity and excellent recognition selectivity towards Al(III). The adsorption capacity of AC-PN-700 towards Al(III) could reach to 3.89?mg.g^?1, removal rate towards Al(III) was almost 100%, and relative selectivity coefficients with respect to La(III) is 9.5. The empirical Freundlich isotherm was found to describe well the equilibrium adsorption data. In addition, AC-PN-700 possesses better regeneration ability and reusability.     

Diffusion of Pt dimers on a Wulff polyhedral surface

The surface diffusion of Pt dimers on Wulff polyhedral clusters with 586-12934 atoms was studied by the embedded atom method. The minimum energy diffusion path and the corresponding energy barrier for dimer diffusion on cluster surfaces were determined through a combination of the quenched Molecular Dynamics and the Nudged Elastic Band method. It was found that the diffusion of a dimer across the step-edge by dissociation and consecutive single-atom exchange with the edge atoms, rather than diffusion over t...     

在Feshbach-Kerman-Koonin多步理论中P及Q空间的跃迁

存在直接作用时, 在哈密顿量中将包括非对角元, 并导致Feshbach,Kerman和Koonin预平衡反应多步复合理论中P和Q空间的耦合, 得到了理论上更严格的Feshbach, Kerman和Koonin预平衡反应多步复合理论与复合核反应Hauser-Feshbach理论的统一表示, 也改进了与实验结果的符合.     

面向环境应用的超重力反应器强化技术:从理论到工业化

工业酸性气体是造成环境污染的最主要因素之一.本文围绕国家环保超低排放新要求,提出了超重力反应强化理论原理和新途径,利用超重力反应器数量级强化传质和超短停留时间优势,高选择性地从混合酸性气体中反应脱除SO2、H2S或CO2,实现了硫化物超低排放;提出了"科学实验+微观机理模型+宏观CFD模拟"三位一体的超重力反应器放大方法,实现了超重力反应器的工程放大,研制出国际规模最大的超重力反应器(转子直径3.5 m、外壳5 m,气体处理量20×104 m3/h)并投入产业化应用;该强化新技术现已在工业尾气脱SO2、石油炼厂气和海洋天然气脱H2S、电厂烟气脱CO2等环保工程中实现了工业应用和推广.     

负载型ZnO/SiO2及ZnO-SiO2溶胶凝胶催化剂的表面结构研究

催化剂的表面结构不仅影响催化剂的催化活性, 而且还影响反应产物的选择性[1]. 制备催化剂的方法不同, 其表面结构及表面性质也不同[2~4]. 浸渍法简单实用, 有利于得到高分散、晶粒细小的高比表面催化剂, 而溶胶-凝胶法则由于其制备温度较低, 易于形成无定形的或介态的氧化物相[5]而可达到分子级的混合, 其活性组分能有效地嵌入网状结构中, 不易受外界的影响而聚集或长大, 因此对催化剂的稳定性更为有利[6,7].