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排序方式: 共有2125条查询结果,搜索用时 15 毫秒
1.
《Discrete Mathematics》2022,345(9):112949
In this paper, we describe a result on self-conjugate -core partitions with the fixed number of corners. We also define shifted corners of a distinct partition and find formulas for the number of -core partitions and the number of -core shifted Young diagrams with the fixed number of shifted corners. 相似文献
2.
Guangrui Chen Yuxing Yan Dr. Jie Wang Prof. Yong Sik Ok Guiyuan Zhong Prof. Bu Yuan Guan Prof. Yusuke Yamauchi 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(44):19831-19836
Mesoporous core–shell nanostructures with controllable ultra-large open channels in their nanoshells are of great interest. However, soft template-directed cooperative assembly to mesoporous nanoshells with highly accessible pores larger than 30 nm, or even above 50 nm into macroporous range, remains a significant challenge. Herein we report a general approach for precisely tailored coating of hierarchically macro-/mesoporous polymer and carbon shells, possessing highly accessible radial channels with extremely wide pore size distribution from ca. 10 nm to ca. 200 nm, on diverse functional materials. This strategy creates opportunities to tailor the interfacial assembly of irregular mesostructured nanounits on core materials and generate various core–shell nanomaterials with controllable pore architectures. The obtained Fe,N-doped macro-/mesoporous carbon nanoshells show enhanced electrochemical performance for the oxygen reduction reaction in alkaline condition. 相似文献
3.
采用Cundari和Stevens等推导的有效芯势对镧系金属一氢化物进行了理论计算,以探讨镧系金属元素与氢的相互作用。结果表明所有镧系金属一氢化物基态时理论上是稳定的,最稳定的是SmH,最不稳定的是DyH;键长计算结果显示,基态时镧系金属一招兵买马花物有独立王国 收缩现象发生;红外振动频率理论计算值与实验结果一致;成键轨道中,金属原子轨道的贡献主要是s轨道和d轨道:从CeH至ErH(GdH)例外)随着外层电子的增加s轨道成分逐渐增大d轨道成分逐渐减小;从TmH和LuH(包括GdH),成键轨道中金属原子轨道的贡献主要是d轨道,约为90%;约大多数镧系金属一氧化物的成键轨道中金属原子轨道f成分小于1%。 相似文献
4.
Josep Maria Izquierdo 《TOP》2006,14(2):375-398
The paper introduces a refinement of the notion of population monotonic allocation scheme, called regular population monotonic
allocation scheme (regularpmas). This refinement is based on economic situations in which players may have to select new partners from a set of potential
players and in which there exist certain capacity constraints. A sufficient condition for the existence of a regularpmas is given. For the class of games with regularpmas, we prove that the core coincides with the Davis and Maschler and the Mas-Colell bargaining sets. 相似文献
5.
Thorsten Brand Kyle Ratinac Jeffrey V. Castro Robert G. Gilbert 《Journal of polymer science. Part A, Polymer chemistry》2004,42(22):5706-5713
A method was developed for free‐radical polymerization in the confines of a hollow latex particle. Hollow particles were prepared via the dynamic swelling method from polystyrene seed and divinylbenzene and had hollows of 500–1000 nm. So that these hollow poly(divinylbenzene) particles could function as submicrometer reactors, the particles were filled with a monomer (N‐isopropylacrylamide) via the dispersion of the dried particles in the molten monomer. The monomer that was not contained in the hollows was removed by washing and gentle abrasion. Free‐radical polymerization was then initiated by γ radiolysis in the solid state. Transmission electron microscopy showed that poly(N‐isopropylacrylamide) formed in the hollow interior of the particles, which functioned as submicrometer reactors. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 5706–5713, 2004 相似文献
6.
本文提出了一类特殊的n人合作对策模型─—弱1—凸对策,研究了弱1—凸对策的解的性质,并证明弱1—凸对策的解满足所有常见的公理化特征. 相似文献
7.
Franck D'Agosto Marie‐Thrse Charreyre Christian Pichot Robert G. Gilbert 《Journal of polymer science. Part A, Polymer chemistry》2003,41(9):1188-1195
A method is described for synthesizing latex particles with anchored hairs by the grafting of hydrophilic chains, synthesized by reversible addition–fragmentation chain transfer, onto functionalized latex particles. These have the potential to bind biologically active species. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 1188–1195, 2003 相似文献
8.
9.
Sarah Josefsson Rikard Westbom Lennart Mathiasson Erland Bjrklund 《Analytica chimica acta》2006,560(1-2):94-102
Pressurized liquid extractions were performed on eight sediments in order to investigate if a modified US EPA method (100 °C, 100 bar, n-heptane/acetone (1:1), 2 × 5 min) provided exhaustive extractions of polychlorinated biphenyls (PCBs) from sediment, and to study if the extractability of PCBs from the different sediments was affected by characteristics of the sediment. The recovery from the eight native sediments, contaminated in nature, was between 96.4% and 98.9%, as an average of the recoveries from 10 PCB congeners. Hundred percent recovery was defined as the sum of two consecutive extractions (2 × 5 min each) at the stated conditions. The recoveries of the individual congeners were above 94%, except for one congener in one sediment, which had a recovery of 92%. When the recoveries and different characteristics of the sediments were compared, no correlation appeared between recoveries and sediment PCB concentration, total organic carbon (TOC), soot carbon (SC) or amorphous carbon (AC). The fact that carbon did not influence the extractions was somewhat surprising, since previous experiments have indicated a connection. Instead, statistically significant (p < 0.05) correlations were observed for water content and carbon/nitrogen (C/N) ratio. The decrease in recoveries with decreased water content was attributed to less access of the solvent to the analytes due to less matrix swelling. The lowered recoveries with increased C/N ratio can indicate that a difference in structure of the organic matter exists, which influences the binding strength between the analytes and the matrix. The difference in structure can possibly be explained by different origin of the organic matter or by aging effects. Overall the method was found to be exhaustive and the excellent recoveries show that sediment characteristics do not influence the extractions markedly. 相似文献
10.
研究了充有不同温度退火Fe基纳米晶粉芯LC回路的磁致频移特性(MFS),发现充有不同温度退火Fe基纳米晶粉芯LC回路的磁致频移不同,充有经600℃退火Fe基纳米晶粉芯LC回路的磁致频移最灵敏。 相似文献