Rapid extra-/intracellular biosynthesis of gold nanoparticles by the fungus <Emphasis Type="Italic">Penicillium</Emphasis> sp.

In this work, the fungus Penicillium was used for rapid extra-/intracellular biosynthesis of gold nanoparticles. AuCl₄ ⁻ ions reacted with the cell filtrate of Penicillium sp. resulting in extracellular biosynthesis of gold nanoparticles within 1 min. Intracellular biosynthesis of gold nanoparticles was obtained by incubating AuCl₄ ⁻ solution with fungal biomass for 8 h. The gold nanoparticles were characterized by means of visual observation, UV–Vis absorption spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX). The extracellular nanoparticles exhibited maximum absorbance at 545 nm in UV–Vis spectroscopy. The XRD spectrum showed Bragg reflections corresponding to the gold nanocrystals. TEM exhibited the formed spherical gold nanoparticles in the size range from 30 to 50 nm with an average size of 45 nm. SEM and TEM revealed that the intracellular gold nanoparticles were well dispersed on the cell wall and within the cell, and they are mostly spherical in shape with an average diameter of 50 nm. The presence of gold was confirmed by EDX analysis.     

Investigation of the Effect of Metallic Lewis Acid on the Nitrolysis of [3,7-Diacetyl-1,3,5,7-tetraazabicyclo(3.3.1)-nonane] and Hexamine

The effect of metallic ions on the nitrolysis of DAPT [3,7‐diacetyl‐1,3,5,7‐tetraazabicyclo(3.3.1)nonane] and HA (hexamine) was investigated by experimental and theoretical approaches. The combinatorial reagent, M(NO^?₃)_n/Ac₂/NH₄NO₃ (M=Mg²⁺, Cu²⁺, Pb²⁺, Bi³⁺, Fe³⁺ and Zr⁴⁺), was found to be efficient in the experiment of the nitrolysis of DAPT. A key intermediate during the nitrolysis of DAPT was detected by ¹H NMR. The formation mechanism of the intermediate was proposed and analyzed. Some discrepant results for the nitrolysis of DAPT and HA catalyzed by different metallic nitrates were explained based on hard‐soft and acid‐base principle and stabilized energy of ion‐complex. From the latter point of view, some cations with high polarizable ligands, e.g., OSO₂CF₃^?, (CF₃SO₂)₂N^?, and (C₄F₉SO₂)₂N^?, can increase the yields. Two newly designed catalysts, Cu[(CF₃SO₂)₂N]₂ and Cu[(C₄F₉SO₂)₂N]₂, were tested to be highly efficient.     

Estimations for ultimate boundary of a new hyperchaotic system and its simulation

This paper has investigated the boundedness of a new hyperchaotic Rabinovich system. We have obtained the global exponential attractive set and the ultimate bound Ω _λ for this system. Furthermore, we can conclude that the rate of the trajectories of the system going from the exterior of the set Ω _λ,2 to the interior of the set Ω _λ,2 is an exponential rate. The estimate of the trajectories rate is also obtained. Numerical simulations are presented to show the effectiveness of the proposed scheme.     

Global dissipativity of a class of BAM neural networks with time-varying and unbound delays

In this paper, we study the global dissipativity of a class of BAM neural networks with both time-varying and unbound delays. Based on Lyapunov functions and inequality techniques, several algebraic criteria for the global dissipativity are obtained. And the linear matrix inequality (LMI) approach is exploited to establish sufficient easy-to-test conditions which are related to the derivative of delay for the global dissipativity. Meanwhile, the estimations of the positive invariant set, globally attractive set and globally exponential attractive set are given out. Finally, two examples are presented and analyzed to demonstrate our results.     

A bi-objective hierarchical program scheduling problem and its solution based on NSGA-III

In enterprise project management systems, a program at the tactical level coordinates and manages multiple projects at the operational level. There are close relationships between multiple projects in a program, which are typically manifested as shared resources and precedence relationships. Most research efforts have concentrated on the resource sharing by projects, while the precedence relationships between projects have yet to be comprehensively investigated. In this paper, a bi-objective hierarchical resource-constrained program scheduling problem proposed, where both resource sharing and precedence relationships between projects are considered in a distributed environment. The problem contains two different sub-problems at the operational level and the tactical level, and they are modeled in the same way as two bi-objective multi-mode scheduling problems. Shared resources are allocated from the tactical level to the operational level, and once they are allocated to a project, they can only be re-allocated to other projects once the current project is finished. Subsequently, a two-phase algorithm based on NSGA-III is developed. The algorithm runs at the operational level and the tactical level in turn. According to the Pareto fronts of projects that are submitted from the operational level, the bi-objective program planning at the tactical level is conducted under the constraints of precedence relationships and shared resources. The results of computational simulations demonstrate the satisfactory performance of the improved algorithm. By coordinating the local optimization of projects and the global optimization of the program in a hierarchical framework, the method proposed in this paper provides an effective integrated scheduling method for decision-makers at various levels of a program.

     

On T-Spline Classification

The present paper conjectures a topological condition which classifies a T-spline into standard, semi-standard and non-standard. We also provide the basic framework to prove the conjecture on the classification of semi-standard T-splines and give the proof for the semi-standard of bi-degree (1, $d$) and ($d$, 1) T-splines.     

Polymeric nanoparticles from rapid expansion of supercritical fluid solution

In this concept paper we highlight applications of supercritical fluid technology in particle formation and production, especially some recent advances in the rapid expansion of supercritical solutions (RESS) processing technique. We also highlight the simple but significant modification to the traditional RESS by using a liquid solvent or solution at the receiving end of the supercritical solution expansion, or the rapid expansion of a supercritical solution into a liquid solvent (RESOLV), and applications of the technique to the preparation of nanoparticles. In particular, successes and challenges in the use of RESOLV for nanoscale (<100 nm) polymeric particles and the subsequent protection of the suspended nanoparticles from agglomeration are discussed.     

Direct Electrochemistry and Electrocatalysis of Hemoglobin in Lipid Film Incorporated with Room‐Temperature Ionic Liquid

A facile phospholipid/room‐temperature ionic liquid (RTIL) composite material based on dimyristoylphosphatidylcholine (DMPC) and 1‐butyl‐3‐methylimidazolium hexafluorophosphate ([bmim]PF₆) was exploited as a new matrix for immobilizing protein. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were adopted to characterize this composite film. Hemoglobin (Hb) was chosen as a model protein to investigate the composite system. UV‐vis absorbance spectra showed that Hb still maintained its heme crevice integrity in this composite film. By virtue of the Hb/DMPC/[bmim]PF₆ composite film‐modified glassy carbon electrode (GCE), a pair of well‐defined redox peaks of Hb was obtained through the direct electron transfer between protein and underlying GCE. Moreover, the reduction of O₂ and H₂O₂ at the Hb/DMPC/[bmim]PF₆ composite film‐modified GCE was dramatically enhanced.     

Rhodium(III)-catalyzed chemodivergent annulations between phenyloxazoles and diazos via C–H activation

Acid-controlled, chemodivergent and redox-neutral annulations for the synthesis of isocoumarins and isoquinolinones have been realized via Rh(III)-catalyzed CH activation. Diazo compounds act as a carbene precursor, and coupling occurs in one-pot process, where adipic acid and trimethylacetic acid promote chemodivergent cyclizations.     

光折变介质中空间光孤子自弯曲现象研究

光折变非线性介质在外加直流电压时会引起介质内部电荷移动,而移动后的电荷又会导致空间电荷的扩散效应,从而产生非局域非线性现象。从理论上研究了具有流动和扩散非局域非线性的光折变晶体中所支持的空间光学孤子的传播行为。应用等效粒子近似方法分析了这类介质中(1 1)维空间光学孤子动力学行为,得出孤子运动"加速度"显式解。孤子的有效"加速度"决定于孤子参量和光折变非局域参量。所得的解析结果可在一定参量范围内直接用来计算孤子的传播轨迹。对孤子在光折变非局域非线性作用下的传播动力学行为做了仿真模拟,数值模拟结果与理论分析结论符合得很好。