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51.
Dahui Luo JinRong Wang Dong Shen 《Mathematical Methods in the Applied Sciences》2019,42(13):4543-4553
This paper considers the consensus tacking problem for nonlinear fractional‐order multiagent systems by presenting a PDα‐type iterative learning control update law with initial learning mechanisms. The asymptotical convergence of the proposed distributed learning algorithm is strictly proved by using the properties of fractional calculus. A sufficient condition is derived to guarantee the whole multiagent system achieving an asymptotic output consensus. An illustrative example is given to verify the theoretical results. 相似文献
52.
Nanogels (NGs) are 3‐dimensional (3D) networks composed of hydrophilic or amphiphilic polymer chains, allowing for effective and homogeneous encapsulation of drugs, genes, or imaging agents for biomedical applications. Polyethylenimine (PEI), possessing abundant positively charged amine groups, is an ideal platform for the development of NGs. A variety of effective PEI‐based NGs have been designed and much effort has been devoted to study the relationship between the structure and function of the NGs. In particular, PEI‐based NGs can be prepared either using PEI as the major NG component or using PEI as a crosslinker. This review reports the recent progresses in the design of PEI‐based NGs for gene and drug delivery and for bioimaging applications with a target focus to tackle the diagnosis and therapy of cancer. 相似文献
53.
Jiaxin Fu Yingxiong Wang Kaizhi Shen Qiang Fu Jie Zhang 《Journal of Polymer Science.Polymer Physics》2019,57(10):598-606
Many experimental results have revealed that the re‐entanglement kinetics of disentangled polymers is much slower than that predicted by tube theory. This retarded recovery of fully entangled state is of practical significance that shear‐induced modification may offer a way to improve processability for a polymer by reducing viscosity. This work tried to figure out the shear‐rate dependence variation of viscosity in the view of evolution of entanglement state through disentanglement and re‐entanglement, aiming to provide fundamental insights into application prospect of shear‐induced modification in preparing “in‐pellet” disentangled polymers prior to final processing. High‐density polyethylene was sheared on a parallel‐plate rotational rheometer with a linearly increased shear rate. Results showed that higher shear rate could induce further disentanglement, resulting in a lower viscosity with a reduction rate up to 93.7%, larger molecular weight between entanglements Me , and longer re‐entanglement time. Additionally, less entanglement would give a larger lamellar thickness of sheared samples after nonisothermal crystallization. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019 , 57, 598–606 相似文献
54.
The Ramanujan Journal - In this paper, we study partitions classified by its smallest missing part. Our main theorem is an inequality related to the parity of the smallest missing part of... 相似文献
55.
Celosin A (CA), a natural compound isolated from Celosia argentea L., has been shown significant hepatoprotective effect on AHNP‐induced liver injury. This study described a rapid and sensitive ultra‐high‐pressure liquid chromatography–tandem mass spectrometry (UHPLC–MS/MS) assay for determination of CA in rat plasma. Methanol‐mediated precipitation was used for sample pretreatment. Chromatographic separation was achieved on a T3 column with gradient elution using water and acetonitrile as mobile phase. Determination was obtained using an electrospray ionization source in negative selected reaction monitoring mode at the transitions of m/z 793.3 → m/z 661.2 and m/z 955.6 → m/z 793.2 for CA and IS, respectively. The assay was linear over the concentration range 0.25–2500 ng/mL (r > 0.995) with a lowest limit of quantification (LLOQ) of 0.25 ng/mL. The intra‐ and inter‐day precisions (RSD) were 1.65–9.84 and 2.46–13.49%, respectively, while accuracy (RR) ranged from 96.21 to 99.45%, respectively. The recovery ranged from 95.09 to 102.22% and the matrix effect from 98.29 to 100.13%. The analyte was stable under the tested storage conditions. The method has been successfully applied to a preclinical pharmacokinetic study in rats after a single intravenous (2 mg/kg) or oral (50 mg/kg) administration. The oral bioavailability of CA was ~1.94%; in addition, there was no difference between male and female rats. This is the first time of the use of an UHPLC–MS/MS method for determination of CA concentration in rat plasma and for evaluation of its pharmacokinetic behavior. 相似文献
56.
Dr. Jiong Zhou Dr. Guocan Yu Yang Li Jie Shen Mengbin Wang Dr. Zhengtao Li Dr. Peifa Wei Prof. Dr. Jianbin Tang Prof. Dr. Feihe Huang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(63):14447-14453
Cyanide is extremely hazardous to living organisms and the environment. Owing to its wide range of applications and high toxicity, the development of functional materials for cyanide detection and sensing is highly desirable. Host–guest complexation between bis(p-phenylene)-34-crown-10 H and N-methylacridinium salt G remarkably decreases the detection limit for cyanide anions compared with that of the guest itself. The [2]pseudorotaxane selectively recognizes the cyanide anion with high optical sensitivity as a result of the nucleophilic addition of the cyanide anion at the 9-position of G . The host–guest complexation is further incorporated into supramolecular materials for the visual detection of cyanide anions, especially the detection of cellular cyanide excretion with a detection limit of 0.6 μm . This supramolecular method provides an extremely distinct strategy for the visual detection of cyanide anions. 相似文献
57.
In this paper, we summarize the existing methods of solving the evolution equation of the leading-twist \begin{document}$B$\end{document} ![]()
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-meson LCDA. Then, in the Mellin space, we derive a factorization formula with next-to-leading-logarithmic (NLL) resummation for the form factors \begin{document}$F_{A,V}$\end{document} ![]()
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in the \begin{document}$B \to \gamma \ell\nu$\end{document} ![]()
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decay at leading power in \begin{document}$\Lambda/m_b$\end{document} ![]()
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. Furthermore, we investigate the power suppressed local contributions, factorizable non-local contributions (which are suppressed by \begin{document}$1/E_\gamma$\end{document} ![]()
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and \begin{document}$1/m_b$\end{document} ![]()
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), and soft contributions to the form factors. In the numerical analysis, which employs the two-loop-level hard function and the jet function, we find that both the resummation effect and the power corrections can sizably decrease the form factors. Finally, the integrated branching ratios are also calculated for comparison with future experimental data. 相似文献
58.
This paper presents a novel genetic algorithm for globally solving un-constraint optimization problem.In this algorithm,a new real coded crossover operator is proposed firstly.Furthermore,for improving the convergence speed and the searching ability of our algorithm,the good point set theory rather than random selection is used to generate the initial population,and the chaotic search operator is adopted in the best solution of the current iteration.The experimental results tested on numerical benchmark functions show that this algorithm has excellent solution quality and convergence characteristics,and performs better than some algorithms. 相似文献
59.
Wei Yao Zhoufeng Shen Yi Yu Guanghong Ding 《Mathematical Methods in the Applied Sciences》2020,43(4):1555-1564
Acupuncture, a physiotherapy, has been widely accepted all around the world. This study focuses on the influence of membrane structures and explains the acupuncture sensations from the aspect of mechanical properties. By mathematical modeling and numerical simulation, the scientific meaning of the acupuncture depth is investigated and phenomena and theory of acupuncture are discussed. The simulation results show that (a) the fascial structure is the main contributor to the force on the needle, the axial force will gradually increase before piercing the fascial, and suddenly decrease after piercing the fascial; (b) there is an inverse relationship between the needle radius and the maximum radial stress, which indicates that the needle should not be too sharp to cause local stress concentration and piece the fascia layer; and (c) the simulation results of comprehensively considering the static friction and sliding friction is identical with the experiment results. This study proposes a preliminary study of mechanical effects of acupuncture manipulation, clarifies key factors affecting the stress on the needle, and explains the objective requirement of acupuncture depth to effective treatment. 相似文献
60.
Dr. Yukun Zhu Chunxiao Lv Zhuocheng Yin Prof. Jun Ren Prof. Xianfeng Yang Prof. Chung-Li Dong Prof. Hongwei Liu Dr. Rongsheng Cai Yu-Cheng Huang Prof. Wolfgang Theis Prof. Shaohua Shen Prof. Dongjiang Yang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(2):878-883
Red phosphorus is a promising photocatalyst with wide visible-light absorption up to 700 nm, but the fast charge recombination limits its photocatalytic hydrogen evolution reaction (HER) activity. Now, [001]-oriented Hittorf's phosphorus (HP) nanorods were successfully grown on polymeric carbon nitride (PCN) by a chemical vapor deposition strategy. Compared with the bare PCN and HP, the optimized PCN@HP hybrid exhibited a significantly enhanced photocatalytic activity, with HER rates reaching 33.2 and 17.5 μmol h−1 from pure water under simulated solar light and visible light irradiation, respectively. It was theoretically and experimentally indicated that the strong electronic coupling between PCN and [001]-oriented HP nanorods gave rise to the enhanced visible light absorption and the greatly accelerated photoinduced electron–hole separation and transfer, which benefited the photocatalytic HER performance. 相似文献