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101.
The design and exploration of efficient, stable and environmentally compatible organic emitters for an electrochemiluminescence (ECL) sensor is a promising topic. Herein, a novel environmentally-friendly luminophore, ZnBCBTP@MWCNTs, were fabricated via self-assembly of porphyrin molecules (ZnBCBTP) onto multi-walled carbon nanotubes (MWCNTs). The resulting luminophore ZnBCBTP@MWCNTs displayed not only the highly ECL property and but also the good accelerated electron mobility. Then, a label-free ECL biosensor based ZnBCBTP@MWCNTs was constructed for the ultrasensitive detection of uric acid. Excitingly, this proposed ECL biosensor performed a good linear relationship in the range of 0–300 μM with a low detection limit of 1.4 μM, thus offering another reliable and feasible sensing platform for clinical bioanalysis with good selectivity, stability, and repeatability.  相似文献   
102.
Zhang  Jian  Qi  Naiming  Jiang  Jihai 《Fluid Dynamics》2021,56(3):371-382
Fluid Dynamics - The collapse of cavitation bubbles in a hydraulic system generates localized zones of high temperature and pressure and, under certain conditions, luminescence. In this study, we...  相似文献   
103.
Applied Mathematics and Mechanics - Through theoretical analysis and finite element simulation, the low-velocity impact of rectangular foam-filled fiber metal laminate (FML) tubes is studied in...  相似文献   
104.
105.
The satisfiability (SAT) problem is a core problem in computer science. Existing studies have shown that most industrial SAT instances can be effectively solved by modern SAT solvers while random SAT instances cannot. It is believed that the structural characteristics of different SAT formula classes are the reasons behind this difference. In this paper, we study the structural properties of propositional formulas in conjunctive normal form (CNF) by the principle of structural entropy of formulas. First, we used structural entropy to measure the complex structure of a formula and found that the difficulty solving the formula is related to the structural entropy of the formula. The smaller the compressing information of a formula, the more difficult it is to solve the formula. Secondly, we proposed a λ-approximation strategy to approximate the structural entropy of large formulas. The experimental results showed that the proposed strategy can effectively approximate the structural entropy of the original formula and that the approximation ratio is more than 92%. Finally, we analyzed the structural properties of a formula in the solution process and found that a local search solver tends to select variables in different communities to perform the next round of searches during a search and that the structural entropy of a variable affects the probability of the variable being flipped. By using these conclusions, we also proposed an initial candidate solution generation strategy for a local search for SAT, and the experimental results showed that this strategy effectively improves the performance of the solvers CCAsat and Sparrow2011 when incorporated into these two solvers.  相似文献   
106.
In this paper we consider iteration of single-plateau functions, an important class of continuous functions with infinitely many forts, and investigate changes of number and length of plateaux under iteration.We use the indices flatness, plateau limit and limit length to formulate those changes. Furthermore, we compute the flatness, plateau limit and limit length for all the nine types of single-plateau functions.  相似文献   
107.
Zhang  F.  Yi  S. H.  Niu  H. B.  Lu  X. G.  Wang  X. X. 《Fluid Dynamics》2021,56(3):383-392
Fluid Dynamics - To predict the boundary layer transition on swept wings, experimental and numerical researches were conducted to obtained the accurate boundary layer transition front and to...  相似文献   
108.
Molecular Diversity - According to the fact that 5-nitro-3-trinitromethyl-1H-1,2,4 triazole (NTNMT) is a successful, good explosive, energetic groups such as –CH3, –NH2, –NHNO2,...  相似文献   
109.
单碱基错配的识别和稳定性差异在核酸多态性研究中至关重要。在同一电化学传感器平台上,采用电化学发光(ECL)和电化学阻抗(EIS)2种技术,协同研究DNA链中不同类型和不同位点的单碱基错配识别和稳定性差异。电极表面具有茎环构象的探针DNA与完全互补DNA、不同类型或不同位点单碱基错配DNA杂交前后的ECL和EIS信号强度变化有显著差异。信号强度变化可揭示单碱基错配识别的稳定性。结果表明,DNA链中心位点的C-A单碱基错配稳定性低于链两端的,靠近键合电极表面双链链端的C-A单碱基错配稳定性低于非键合电极表面双链链端的,同一中心位点C-X碱基对的稳定性顺序为C-G?C-T>C-A≥C-C。研究结果可为核酸多态性研究提供参考。  相似文献   
110.
Xu  H. J.  Zhang  Q. G.  Debenest  G. 《Transport in Porous Media》2021,140(3):625-627
Transport in Porous Media - The theme of coupling problems for adsorption, absorption and thermochemical transport in porous media is very important for engineering applications. Based on the...  相似文献   
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