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131.
A.D. López-Sánchez A.G. Hernández-Díaz D. Vigo R. Caballero J. Molina 《European Journal of Operational Research》2014
The aim of this paper is to solve a real-world problem proposed by an international company operating in Spain and modeled as a variant of the Open Vehicle Routing Problem in which the makespan, i.e., the maximum time spent on the vehicle by one person, must be minimized. A competitive multi-start algorithm, able to obtain high quality solutions within reasonable computing time is proposed. The effectiveness of the algorithm is analyzed through computational testing on a set of 19 school-bus routing benchmark problems from the literature, and on 9 hard real-world problem instances. 相似文献
132.
《Electrophoresis》2018,39(8):1040-1047
Isoelectric focusing (IEF) is a powerful separation method, useful for resolving subtle changes in the isoelectric point of unlabeled proteins. While microfluidic IEF has reduced the separation times from hours in traditional benchtop IEF to minutes, the enclosed devices hinder post‐separation access to the sample for downstream analysis. The two‐layer open IEF device presented here comprises a photopatterned hydrogel lid layer containing the chemistries required for IEF and a thin polyacrylamide bottom layer in which the analytes are separated. The open IEF device produces comparable minimum resolvable difference in isoelectric point and gradient stability to enclosed microfluidic devices while providing post‐separation sample access by simple removal of the lid layer. Further, using simulations, we determine that the material properties and the length of the separation lanes are the primary factors that affect the electric field magnitude in the separation region. Finally, we demonstrate self‐indexed photomasks for alignment‐free fabrication of multi‐domain hydrogels. We leverage this approach to generate arrayed pH gradients with a total of 80 concurrent separation lanes, which to our knowledge is the first demonstration of multiple IEF separations in series addressed by a single pair of electrodes. 相似文献
133.
采用UG的二次开发工具集UG/Open实现了麻花钻的参数化设计计算,并结合UG/Open API与GRIP技术建立了麻花钻参数化设计界面,实现麻花钻的自动建模,最后采用API与MFC建立麻花钻参数化数据库,解决了API应用程序不能直接支持MFC的问题。系统将参数化设计与数据库技术相结合,提高了麻花钻的设计效率与准确性,缩短了设计周期。 相似文献
134.
西科大临潼校区三维虚拟校园系统设计实现 总被引:3,自引:0,他引:3
针对西科大临潼校区宣传的需求,基于3D Max和OSG设计实现了一套临潼校区三维虚拟校园系统。首先,应用3D Max对整个临潼校区进行三维建模,提出了一种大规模建筑物场景的划分建模方法。然后,基于VS2005和OSG对临潼校区三维虚拟校园系统进行设计实现,提出了一种自主漫游碰撞检测方法,并实现了自动路径场景定位功能。应用结果表明,该系统达到了实时三维交互需求和预期显示效果。 相似文献
135.
运用数理统计等方法,对2013年澳网女单8强进行了聚类和比较分析.结果显示,发球时速和制胜分的差距是当今高水平女子网球运动员之间技术水平存在细微差距的主要原因.另外,李娜的技战术水平已达世界一流水平,提高发球速度仍是其下一步努力的方向. 相似文献
136.
Yang Yang Yongnan Zhao Jianguo Yu Yang Zhou Nan Pang Hao Su Sha Pang 《无机化学与普通化学杂志》2008,634(10):1780-1784
Two new open‐framework zincophosphites, Zn(H6C4N2S)(HPO3) (TJPU‐4) and [C6N2H14]·[Zn3(HPO3)4] (TJPU‐5) have been hydrothermally synthesized by using 2‐mercapto‐1‐methylimidazole [MMI] and 1,4‐diazabicyclo[2.2.2]octane [DABCO] as templates. TJPU‐4 crystallizes in monoclinic space group P21/c with the cell parameters a = 8.787(4) Å, b = 9.732(4) Å, c = 10.515(4) Å, β = 105.316(6)°, V = 867.3(6) Å3. The structure of TJPU‐4 is constructed by ZnO3S tetrahedron and HPO3 pseudo‐pyramid to generate a layer of 4, 8‐network in bc plane. The organic template locates on the both sides of the 8‐membered rings and bonds to zinc atom through Zn–S bond. TJPU‐5 crystallizes in the triclinic space group with cell parameters a = 9.294 (5) Å, b = 9.976 (5) Å, c = 9.986 (5) Å, α = 85.692 (7)°, β = 82.010 (7)° and γ = 80.184 (7)°, V = 902.1 (8) Å3. A novel 4488 cage is found in TJPU‐5. The connections of Zn(1)O4, Zn(3)O4 and HPO3 groups give rise to an infinite corner‐shared four‐ring chain. Using Zn(2)O4 as four connected bridges, linkages of these chains produce a 3‐D framework with intersecting 8‐ring channels running along [100], [010], [001], [011] and [111] directions. 相似文献
137.
Hanseok Yi Dr. Suhwan Song Sang Myeong Han Jieun Lee Prof. Dr. Woojae Kim Prof. Dr. Eunji Sim Prof. Dr. Dongil Lee 《Angewandte Chemie (International ed. in English)》2023,62(33):e202302591
We report a new strategy in which a thiolate-protected Ag25 nanocluster can be doped with open d-shell group 8 (Ru, Os) and 9 (Ir) metals by forming metal hydride (RuH2, OsH2, IrH) superatoms with a closed d-shell. Structural analyses using various experimental and theoretical methods revealed that the Ag25 nanoclusters were co-doped with the open d-shell metal and hydride species to produce superatom-in-superatom nanoclusters, establishing a novel superatom doping phenomenon for open d-shell metals. The synthesized superatom-in-superatom nanoclusters exhibited dopant-dependent photoluminescence (PL) properties. Comparative PL lifetime studies of the Ag25 nanoclusters doped with 8–10 group metals revealed that both radiative and nonradiative processes were significantly dependent on the dopant. The former is strongly correlated with the electron affinity of the metal dopant, whereas the latter is governed predominantly by the kernel structure changed upon the doping of the metal hydride(s). 相似文献
138.
李国立 《河南师范大学学报(自然科学版)》2014,(1):180-184
为了探寻网球比赛的制胜规律,通过查阅近期结束的中国网球公开赛官方网站发布的技术统计指标,采用文献资料法和数理统计法对参加2013年女子单打比赛的46名球员在比赛中的技术数据进行了统计分析,并建立了影响每名球员比赛制胜能力的最优化模型.研究表明:影响各球员制胜能力的技术指标按照程度由大到小依次是:发球得分数、挽回破发点、破发成功、发球数这4个主要因素.建议:中国网球队球员应针对技术制胜指标进行高效率训练,并根据自身能力对自己的发展空间进行科学的预测和把握. 相似文献
139.
Dr. Feifei Zhang Dr. Hua Shang Bolun Zhai Zhiwei Zhao Dr. Yong Wang Prof. Libo Li Prof. Jinping Li Prof. Jiangfeng Yang 《Angewandte Chemie (International ed. in English)》2023,62(50):e202316149
Porous materials with d3 electronic configuration open metal sites have been proved to be effective adsorbents for N2 capture and N2/O2 separation. However, the reported materials remain challenging to address the trade-off between adsorption capacity and selectivity. Herein, we report a robust MOF, MIL-102Cr, that features two binding sites, can synergistically afford strong interactions for N2 capture. The synergistic adsorption site exhibits a benchmark Qst of 45.0 kJ mol−1 for N2 among the Cr-based MOFs, a record-high volumetric N2 uptake (31.38 cm3 cm−3), and highest N2/O2 selectivity (13.11) at 298 K and 1.0 bar. Breakthrough experiments reveal that MIL-102Cr can efficiently capture N2 from a 79/21 N2/O2 mixture, providing a record 99.99 % pure O2 productivity of 0.75 mmol g−1. In situ infrared spectroscopy and computational modelling studies revealed that a synergistic adsorption effect by open Cr(III) and fluorine sites was accountable for the strong interactions between the MOF and N2. 相似文献
140.
In this work, a series of new metal phosphonates were hydrothermally synthesized and structurally characterized based on m-xylylenediphosphonic acids (H4L), including [M(H2L)(bpy)] (M = Mn 1, Co 2), [MH2L)(phen)] (M = Co 3, Cu 4), and [Cu2(H2L)2(bpy")2] 5 (bpy = 2,2'-bipyfidine, phen = 1,10-phenanthroline, bpy" = 4,4'-dimethyl-2,2'- bipyridine). X-ray diffraction indicated that compounds 1 and 2 were isomorphic. Complexes 3 and 4 were shown to crystallize in different space groups but had similar crystallographic units. In the complexes, H4L was seen to partially deprotonate to afford H2L^2-. The H2L^2- ligands in 1-4 functioned as tetradentate ligands with each phosphonate group adopting bidentate coordination mode with two M centers to generate a 2D layer. In addition, the H2L^2- anions in 5 functioned as tfidentate ligands with one phosphonate group adopting the bidentate mode and another phosphonate group adopting the monodentate mode, thus linking three Cu atoms to provide a 1D chain. The IR and thermal stabilities of these compounds were subsequently examined. 相似文献