Coumarin-Based Small-Molecule Fluorescent Chemosensors

Cao, Duxia,Liu, Zhiqiang,Verwilst, Peter,Koo, Seyoung,Jangjili, Paramesh,Kim, Jong Seung,Lin, Weiying American Chemical Society 2019 Chemical reviews Vol.119 No.18

<P>Coumarins are a very large family of compounds containing the unique 2<I>H</I>-chromen-2-one motif, as it is known according to IUPAC nomenclature. Coumarin derivatives are widely found in nature, especially in plants and are constituents of several essential oils. Up to now, thousands of coumarin derivatives have been isolated from nature or produced by chemists. More recently, the coumarin platform has been widely adopted in the design of small-molecule fluorescent chemosensors because of its excellent biocompatibility, strong and stable fluorescence emission, and good structural flexibility. This scaffold has found wide applications in the development of fluorescent chemosensors in the fields of molecular recognition, molecular imaging, bioorganic chemistry, analytical chemistry, materials chemistry, as well as in the biology and medical science communities. This review focuses on the important progress of coumarin-based small-molecule fluorescent chemosensors during the period of 2012-2018. This comprehensive and critical review may facilitate the development of more powerful fluorescent chemosensors for broad and exciting applications in the future.</P> [FIG OMISSION]</BR>

An Efficient Spatial Data Index Based On Gossip for Overlay Networks

Zhiqiang Zou,Yue Wang,Kai Cao,Shu Shen,Bin Zhang 한국산학기술학회 2013 SmartCR Vol.3 No.3

In large and highly dynamic distributed environments, the retrieval of spatial data entails some challenges such as network topology, indexing efficiency, and mapping methods for multidimensional spatial data. Conventional methods may not allow for the complex retrieval of multidimensional spatial data in an efficient manner. This paper proposes an overlay network for indexing spatial data based on gossip. The proposed network, referred to as the 2D-Ring, has a ring-like topology with a spatial data index. First, the paper introduces a protocol for constructing an overlay network for indexing spatial data and then presents a method for mapping the data onto the 2D-Ring by using a distributed quadtree and control points. The results of a comprehensive experiment for an evaluation of the performance of the 2D-Ring with respect to various features indicate that the 2D-Ring converges logarithmically to network size, has desirable small-world properties, and is robust across dynamic scenarios. The proposed solution can be applied not only to overlay networks but also to other types of networks requiring the sharing of distributed data sets.

ML-MOEA/SOM : A Manifold-Learning-Based Multiobjective Evolutionary Algorithm Via Self-Organizing Maps

Wei Cao,Wei Zhan,ZhiQiang Chen 보안공학연구지원센터 2016 International Journal of Signal Processing, Image Vol.9 No.7

Under mild conditions, it can be induced from the Karush–Kuhn–Tucker condition that the Pareto set, in the decision space, of a continuous Multiobjective Optimization Problems(MOPs) is a piecewise continuous (m 1)  D manifold(where m is the number of objectives). One hand, the traditional Multiobjective Optimization Algorithms(EMOAs) cannot utilize this regularity property; on the other hand, the Regular Model-Based Multiobjective Estimation of Distribution Algorithm(RM-MEDA) only able to build the linear model of decision space using linear modelling algorithm, such as: the local principal component analysis algorithm(Local PCA).Aim at the shortcomings of EMOAs and RM-MEDA, the Manifold-Learning-Based Multiobjective Evolutionary Algorithm Via Self-Organizing Maps(ML-MOEA/SOM) is proposed for continuous multiobjective optimization problems. At each generation, first, via Self-Organizing Maps, the proposed algorithm learns such a nonlinear manifold in the decision space; then, new trial solutions is built through expanding the neurons of SOM with random noise; at the end, a nondominated sorting-based selection is used for choosing solutions for the next generation. Systematic experiments have shown that, overall, ML-MOEA/SOM outperforms NSGA-II, and is competitive with RM-MEDA in terms of convergence and diversity, on a set of test instances with variable linkages. We have demonstrated that, compared with NSGA-II and RM-MEDA, via self-Organizing maps, ML-MOEA/SOM can dig nonlinear manifold hidden in the decision space of multiobjective optimization problems.

Melting and Casting Processes : EMC TECHNOLOGY STUDY OF ALUMINUM ALLOY BILLETS

Jin JunZe,Cao ZhiQiang,Zhang XingGuo,Zheng XianShu 대한금속재료학회 ( 구 대한금속학회 ) 1995 Advanced Material and Processing Vol.1 No.-

Chemical Bonds-Conjugated Ag2SO3/NaNbO3 Hybrids as Efficient Photocatalysts: In-situ Fabrication, Characterization and Degradation of Rhodamine B and Methyl Orange

Yanmei Feng,Zhiqiang Wang,Yunfeng Yang,Xiang-Feng Wu,Xiaodong Gong,Yajian Liu,Yufei Li,Zuo-Lin Cao,Chao Wang,Xin Tong 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2018 NANO Vol.13 No.7

The Ag2SO3/NaNbO3 hybrids have been fabricated via a facile method at room temperature. Several methods such as X-ray diffraction, UV-Vis diffuse reflectance spectroscopy, scanning electron microscopy, electrochemical impedance spectroscopy and X-ray photoelectron spectroscopy were used to characterize the samples. Moreover, the photocatalytic activity of the samples was assessed by degradation of rhodamine B and methyl orange under the visible light illumination. Experimental results indicated the photocatalytic degradation efficiency of the as-fabricated hybrids was first increased and then decreased with increasing the dosage of NaNbO3. When the molar ratio of Ag2SO3 to NaNbO3 was 1:0.7, the as-fabricated composites had the best photodegradation efficiency of 96.4% in 30 min for rhodamine B and 97.1% in 60 min for methyl orange, respectively. These were obviously higher than that of pure samples. Furthermore, Ag2SO3 was conjugated with NaNbO3 via chemical-bonds rather than physical contact. In addition, the possible photocatalytic degradation mechanism was also provided and the main roles during the process of photocatalytic degradation were played by holes.

Kinetic modeling of non-hydrocarbon/nitric oxide interactions in a flow reactor above 1,400K

Shaozeng Sun,Zhiqiang Wang,Lin Qian,Yukun Qin,Huali Cao 한국화학공학회 2009 Korean Journal of Chemical Engineering Vol.26 No.3

The reduction of nitric oxide by reaction with non-hydrocarbon fuels under reducing conditions at comparatively higher temperature has been studied with a detailed chemical kinetic model. The reaction mechanism consists of 337 elementary reactions between 65 chemical species based on the newest rate coefficients. The experimental data were adopted from previous work. Analyses by comparing existing experimental data with the modeling predictions of this kinetic mechanism indicate that, at comparatively high temperature, apart from the reaction path NO→ HNO→NH→N2, NO+N→N2 is also prominent. In the presence of CO, NO is partly converted to N by reaction with CO. Based on present model, the reduction of NO at high temperature, which was usually underestimated by previous work, can be improved to some extent.

Intelligent Matching Assembly: System Design Based on Reuse of Ultra-Difference Parts

Yongjie Zhang,Kang Cao,Zhiqiang Cai,Xinwen Wang,Wei Jin 한국정밀공학회 2021 International Journal of Precision Engineering and Vol.22 No.7

As the industrial digitalization has been recently leaping forward, high-efficiency production processes emerge, and assembly integration technologies are being progressively developed. For high-tech industries (e.g., aerospace manufacturing), however, unprecedented challenges are imposed on the conventional assembly manufacturing process technology. To be specific, the shallow digitizing and intelligent technologies fail to satisfy the rising requirements for efficiency, pass rates and cost; in particular, the way to down-regulate the unqualified rate and assembly cost of parts production remains unclear. In the present study, an intelligent matching assembly system was designed for reapplying out-of-tolerance parts. In addition, the concept of the mating base is proposed. Next, the fi t relation between parts is quantified by employing the functional expression of dimension data, and such a relation is characterized as a function constraint with a variable of dimension. Moreover, the designed intelligent matching system was introduced into the existing assembly process to reemploy a number of unqualified parts and determine the matching parts most suitable for the original unqualified parts. On that basis, the most suitable parts are enabled to be involved in the assembly activities, as an attempt to satisfy the design requirements. To efficiently find the optimal matching scheme in the database of the unqualified parts and most effectively employ the unqualified parts, a set of optimal matching algorithms are proposed, thereby significantly down-regulating the production cost. Lastly, Monte Carlo method was adopted to simulate the actual production data, and the optimal matching scheme determined by the intelligent matching system was analyzed and assessed, which verified the effectiveness and practicability of the system.

The Interlaminar Mechanical and Impact Properties of Fibre Metal Laminates Reinforced with Graphene

Fanglin Cong,Shuo Wang,Linlin,Meng Cao,Zehui Jia,Zhiqiang Zhou,Xu Cui 한국섬유공학회 2022 Fibers and polymers Vol.23 No.5

Glass fibre aluminium laminate (Glare) is widely used in various fields because of its excellent performance. However, its properties can be further enhanced by adding nanofillers, such as graphene, to the matrix. Graphene is a costeffectivetoughening agent because of its excellent specific strength, economy and good compatibility. The interlaminarmechanical and dynamic impact properties of Glare were improved by uniformly dispersed graphene (0, 0.2, 0.3, 0.5 and1.0 wt%). The interlaminar mechanical properties (short beam shear and single lap test) of the graphene-modified (0.5 wt%)Glare were increased by 42.24 % and 25.65 %, respectively, compared with the pure epoxy resin matrix. At a graphenecontent of 1.0 wt%, the Charpy impact energy and strength increased by 163.58 % and 126.33 %, respectively, and reachedthe maximum value. The microscopic images and schematic diagrams illustrated the toughening mechanism of graphene,including the enhancement of the aluminium/resin and fibre/resin interfaces and the performance of the resin matrix. Thetoughening of the resin matrix was achieved through the formation of a mechanical linkage between the graphene and thematrix, which indicated that more time and energy would be required to destroy it.

Preliminary numerical study on hydrogen distribution characteristics in the process that flow regime transits from jet to buoyancy plume in time and space

Di Wang,Lili Tong,Luguo Liu,XUEWU CAO,Zhiqiang Zou,Lingjun Wu,Xiaowei Jiang 한국원자력학회 2019 Nuclear Engineering and Technology Vol.51 No.6

Hydrogen-steam gas mixture may be injected into containment with flow regime varying both spatiallyand transiently due to wall effect and pressure difference between primary loop and containment insevere accidents induced by loss of coolant accident. Preliminary CFD analysis is conducted to gain informationabout the helium flow regime transition process from jet to buoyancy plume for forthcomingexperimental study. Physical models of impinging jet and wall condensation are validated using separatedeffect experimental data, firstly. Then helium transportation is analyzed with the effect of jetmomentum, buoyancy and wall cooling discussed. Result shows that helium distribution is totallydominated by impinging jet in the beginning, high concentration appears near gas source and wallwhere jet momentum is strong. With the jet weakening, stable light gas layer without recirculating eddyis established by buoyancy. Transient reversed helium distribution appears due to natural convectionresulted from wall cooling, which delays the stratification. It is necessary to concern about hydrogenaccumulation in lower space under the containment external cooling strategy. From the perspective ofexperiment design, measurement point should be set at the height of connecting pipe and near the wallfor stratification stability criterion and impinging jet modelling validation.

Improved Method for Calculating Armature-Reaction Field of Surface-Mounted Permanent Magnet Machines Accounting for Opening Slots

Yu Zhou,Huaishu Li,Qingyu Wang,Zhiqiang Xue,Qing Cao,Shi Zhou 대한전기학회 2015 Journal of Electrical Engineering & Technology Vol.10 No.4

This paper presented an improved analytical method for calculating armature-reaction field in the surface-mounted permanent magnet machines accounting for opening slots. The analytical model is divided into two types of subdomains. The current of the armature is centralized in the center of the slots. The field solution of each subdomain is obtained by applying the interface and boundary conditions of the model. Two 30-pole/36-slot prototype machines with different slot-opening width are used for validation. The FE (finite element) results confirm the validity of the analytical results with the proposed model. The investigation shows that the wider the slot-opening width is, the smaller the peak value of radial and circumferential components of flux density, and the analytical armaturereaction field produced by centralized current in the slots is similar with the armature-reaction field produced by distributed current in the slots in the FE.