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31.
32.
Xiaoyong Chen Zeyu Zhang Jiajie Wu Jiale Wang Aolong Gao 《Particle & Particle Systems Characterization》2021,38(7):2100076
Red fluorescent carbon dots (R-CDs) are special desirable for biochemical analysis due to good biological compatibility and deep penetration; however, they remain as bottlenecks due to difficulties in expanding the sp2 domain, especially those are fused from rigid polycyclic conjugated molecules (RPCMs) with heteroatom substituents due to huge steric hindrance and heteroatom blockage toward graphic lattice. Here, an RPCM with heteroatom substituents, 1,5-diamino-4,8-dihydroxyanthraquinone (DDAQ), based self-doped R-CDs with PL emission at 635 nm is reported. Further investigations reveal that the expanding, hybrid sp2 domain with indanthrone tannin structure from DDAQ is mainly responsible for the obtained red fluorescence of R-CDs. Taking advantage of optical properties, R-CDs are considered to construct a colorimetric/fluorescent dual mode sensing array for quantifying trace levels of Fe3+ and glyphosate based on the static quenching, and a biomarker for cell imaging. The CD-based sensors exhibit outstanding recovery, high selectivity, and sensitivity, also facilitated dual-mode detection with the naked-eye. The R-CDs have low cytotoxicity, good cell membrane penetration for rapid cell entry, and high resolution, demonstrating their potential for biolabeling and bioanalytic applications. 相似文献
33.
为了进一步提高深亚微米SOI (Silicon-On-Insulator) MOSFET (Metal-Oxide Semiconductor Field Effect Transistor) 的电流驱动能力, 抑制短沟道效应和漏致势垒降低效应, 提出了非对称Halo异质栅应变Si SOI MOSFET. 在沟道源端一侧引入高掺杂Halo结构, 栅极由不同功函数的两种材料组成. 考虑新器件结构特点和应变的影响, 修正了平带电压和内建电势. 为新结构器件建立了全耗尽条件下的表面势和阈值电压二维解析模型. 模型详细分析了应变对表面势、表面场强、阈值电压的影响, 考虑了金属栅长度及功函数差变化的影响. 研究结果表明,提出的新器件结构能进一步提高电流驱动能力, 抑制短沟道效应和抑制漏致势垒降低效应, 为新器件物理参数设计提供了重要参考.
关键词:
非对称Halo
异质栅
应变Si
短沟道效应 相似文献
34.
Agnieszka Ksiazek 《Molecular physics》2013,111(6):769-786
The dual basis set approach has proven to be very successful for accurately estimating total energies with large basis sets. This study extends the applications of this technique to the calculation of molecular properties, including energy derivatives with respect to nuclear positions and to an external electric field. All energy derivatives have been calculated numerically via finite-differences. Molecular gradients and Hessians as well as dipole moments and polarizabilites have been calculated at the HF and MP2 levels using two alternative versions of the dual basis set method. The accuracy of these approaches is discussed in the context of quality of basis sets used in calculations. It is shown that even quite poor results obtained with the 6-311G basis set are significantly improved in dual basis set calculations with the 6-311G(d,p) and 6-311G(3df,3dp) basis sets. 相似文献
35.
Two different ways to form monolayers and LB films (surface film and subphase film) of the complex have been used, where a novel amphiphile containing Schiff base as a headgroup was used as a ligand. the monolayer behavior at the air/water interface was characterized by π-A isotherms and two-dimensional molecular orientation of alkyl chains in LB films and thermal stability were measured by polarized and variable temperature FTIR transmission spectra, indicating that the LB film of the novel amphiphile and its copper(II) complex are very stable as well as stearic acid. Because incorporating the metal ion into the monolayer makes it more condensed, thermal stability of the LB film was enhanced. as can be compared from their structure and properties, subphase films are superior to surface films. 相似文献
36.
The purpose of this study was to evaluate the changes of noise and computer tomography (CT) number in each dental substance, by using the metal artefact reduction algorithm; we used dual CT for this study. For the study, we produced resin, titanium, gypsum, and wax that are widely used by dentists. In addition, we made nickel to increase the artefact. While making the study materials, we made sure that there is no difficulty when inserting the substances inside phantom. In order to study, we scanned before and after using the metal artefact reduction algorithm. We conducted an average analysis of CT number and noise, before and after using the metal artefact reduction algorithm. As a result, there was no difference in CT number and noise before and after using the metal artefact reduction algorithm. However, when it comes to the noise value in each substance, wax's noise value was the lowest whereas titanium's noise value was the highest, after applying the metal artefact reduction algorithm. In nickel, CT number and noise value from artefact area showed a decreased noise value when applying the metal artefact reduction algorithm. In conclusion, we assumed that we could increase the effectiveness of CT examination by applying dual energy's metal artefact reduction algorithm. 相似文献
37.
Ben Salem Nejib 《Journal of Theoretical Probability》1994,7(2):417-436
We consider hypergroups associated with Jacobi functions
()
(x), (–1/2). We prove the existence of a dual convolution structure on [0,+[i(]0,s
0]{{) =++1,s
0=min(,–+1). Next we establish a Lévy-Khintchine type formula which permits to characterize the semigroup and the infinitely divisible probabilities associated with this dual convolution, finally we prove a central limit theorem. 相似文献
38.
提出了一款具有高隔离度的双陷波超宽带多入多出(UWB MIMO)天线。该天线由两个相同的半切超宽带天线单元倒置构成。通过在天线底板刻蚀栅栏型缺陷地解耦结构,使该MIMO天线的隔离度提高至25 dB。此外,在天线半圆形辐射贴片上刻蚀两个方向相反的“L”型缝隙,实现了双陷波的功能,分别抑制了802.16无线城域网WiMAX(3.2~3.7 GHz)和WLAN(5.15~5.85 GHz)信号对天线系统的干扰。实验结果表明,该天线在3~11 GHz工作带宽内的隔离度大于25 dB,包络相关系数(ECC)小于0.004;第一个陷波频段为3.0~3.7 GHz,第二个陷波频段为5.1~5.85 GHz,有效抑制了WiMAX和WLAN的信号干扰。 相似文献
39.
余桑 《应用数学和力学(英文版)》1987,8(12):1115-1131
Despite its beauty and grandeur the theory of GR still appears to be incomplete in thefollowing ways:(1)It cannot accommodate the asymmetric total energy momentum tensor whoseasymmetry has been shown to exist in the presence of electromagnetism.(2)The law of angular momentum balance as an exact equation is not an automaticconsequence of the field equations as is the case with the law of linear momentum balance.(3)The four degrees of arbitrariness left by the contracted second Bianchi identitymakes a unique solution of the field equations unattainable without extra (unphysical)postulates.To answer the challenge posed by the above assertions we propose in this paper tocomplete Einstein’s theory by postulating the principle fibre bundle P[M,SU(2)]for theunderlying geometry of the 4-dimensional spacetime,where the structre group SU (2) isthe real representation of the special complex unitary group of dimension 2. SU (2) leavesconcurrently invariant the metric form dS~2=g_(αβ)dx~αdx~β and the fundamenta 相似文献
40.
通过分析计算,设计了一种大口径宽视场折射式红外相机光学系统。该系统设计用于超长线阵扫描红外相机的地面演示成像,它能同时对短波2μm—3μm、中波3μm—4.5μm双波段成像,且同时具有24°的大视场和150mm的宽口径,成像质量接近衍射极限。该系统在航天遥感领域应用广泛。 相似文献