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11.
Tran Thu Ha Nguyen Hong Phong François-Xavier Le Dimet Hong Son Hoang 《Comptes Rendus Mecanique》2019,347(5):423-444
This article presents a correction method for a better resolution of the problem of estimating and predicting pollution, governed by Burgers' equations. The originality of the method consists in the introduction of an error function into the system's equations of state to model uncertainty in the model. The initial conditions and diffusion coefficients, present in the equations for pollution and concentration, and also those in the model error equations, are estimated by solving a data assimilation problem. The efficiency of the correction method is compared with that produced by the traditional method without introduction of an error function.Three test cases are presented in this study in order to compare the performances of the proposed methods. In the first two tests, the reference is the analytical solution and the last test is formulated as part of the “twin experiment”.The numerical results obtained confirm the important role of the model error equation for improving the prediction capability of the system, in terms of both accuracy and speed of convergence. 相似文献
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Dr. Chaolu Eerdun Thi Hien Thuy Nguyen Takuya Okayama Satoshi Hisanaga Prof. Dr. Jun-ichiro Setsune 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(22):5777-5786
The hexapyrrole-α,ω-dicarbaldehydes 1 a and 1 b were metallated with CuII, NiII, and PdII to give bimetallic complexes where a pair of 3 N+O four-coordinate metal planes are helically distorted and the central 2,2′-bipyrrole subunit adopts a cis or trans conformation. X-ray crystallographic analysis of the bisCu complex revealed a closed form with a cis-2,2′-bipyrrole subunit and an open form with a trans-2,2′-bipyrrole subunit. The bisPd complexes took a closed form both in the solid state and in solution. They are regarded as single helicates of two turns and the energy barrier for the interchange between an M helix and a P helix was remarkably influenced by the bulky 3,3′-substituent of the central 2,2′-bipyrrole subunit. Although the bisNi complexes adopt a closed form in the solid state, they exist as a homohelical open C2-symmetric form or a heterohelical open Ci-symmetric form in solution. A theoretical study suggested that the closed form of 1 a Pd was stabilized by the Pd–Pd interaction. Compound 1 a Pd was reversibly oxidized by one electron at 0.14 V versus ferrocene/ferrocenium (Fc/Fc+) and this oxidized species showed Vis/NIR absorption bands at λ=767 and 1408 nm. 相似文献
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Phu H. Dang Linh T. T. Nguyen Hue T. T. Nguyen Tho H. Le Truong N. V. Do Hai X. Nguyen 《Natural product research》2019,33(20):2883-2889
From an EtOAc-soluble fraction of the stem barks of Swintonia floribunda (Anacardiaceae), one new dimeric alkylresorcinol named integracin E (1), together with 4 known compounds (2–5) were isolated. Their chemical structures were elucidated based on the spectroscopic data interpretation. The absolute configuration of 1 was determined by the specific rotation analysis of its acid-catalyzed hydrolysis product. Compound 1 showed potent tyrosinase inhibitory activity with an IC50 value of 48.2?μM. 相似文献
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Nguyen Van Hung Vo Minh Tam Dumitru Baleanu 《Mathematical Methods in the Applied Sciences》2020,43(7):4614-4626
In this paper, we consider a class of split mixed vector quasivariational inequality problems in real Hilbert spaces and establish new gap functions by using the method of the nonlinear scalarization function. Further, we obtain some error bounds for the underlying split mixed vector quasivariational inequality problems in terms of regularized gap functions. Finally, we give some examples to illustrate our results. The results obtained in this paper are new. 相似文献
16.
Srinivasa Reddy Mallampati Chi Hyeon Lee Nguyen Thi Thanh Truc Byeong-Kyu Lee 《International journal of environmental analytical chemistry》2015,95(12):1081-1089
The recovery of precious metals from automotive shredder residue (ASR) dust/combustion residue is an option that is not usually considered due to the lack of available information. Therefore, before any disposal or recovery application can be considered, it is necessary to determine the significance of the levels and distribution of precious metal in ASR dust/ASR combustion residue. In the present study, quantitative analysis of precious metals (Pt, Pd, Au, Ag and Cu) in the ASR residue samples was performed using energy dispersive X-ray (EDX) fluorescence spectrometer. With the fundamental parameter (FP) method, the X-ray intensity is obtained and the quantitative analysis is performed using theoretical calculation. This method is very effective for quantitative analysis of unknown samples without standard samples. Further, in order to analyse the precious metal distribution within the ASR combustion residues, the microstructural characterisation and elemental mapping were also carried out with the aid of field emission scanning election microscopy combined with electron dispersive spectroscopy (FE-SEM EDS). Significant amount of Pt, Pd, Au, Ag and Cu element concentrations in the ASR residue were identified. Total precious (Pt, Pd, Au, Ag and Cu) metals obtainable values are representing about 12.23 wt% from its initial ASR dust/combustion residues. Considering their relevant concentrations, these metals should be properly recovered for recycling purposes before to dispose or landfill. 相似文献
17.
水质评价涉及属性权与熵权两种权重.熵权表征因子的分类能力,由因子的隶属度向量通过计算信息熵确定.属性权表征因子重要性程度的差异,用途是使不同因子的隶属度具有"可比性",但定权方法众说不一.指出,因子重要性程度差异源于因子属性与因子取值无关,并且表征这种差异等同于对因子接重要性排序.AHP的比例标度判断矩阵为因子排序提供了合理的数据条件,但基于"一致性检验"的特征根排序法受到质疑;FAHP也因没有彻底摆脱"一致性",所以建立的排序方法有局限性.为此,通过标度变换将比例标度转化为评分标度,利用评分标度的可加性把判断矩阵中由评分标度确定的因子的序关系转化为因子排序.由此建立不受"一致性"干扰的定权方法. 相似文献
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Regular conjugated terpolymers comprising two different acceptors and bithiophene donor in repeating group: Effect of strong and weak acceptors on semiconducting properties 下载免费PDF全文
Duc Nghia Nguyen Trinh Tung Ngo Dae Hee Lee Min Ju Cho Dong Hoon Choi 《Journal of polymer science. Part A, Polymer chemistry》2016,54(10):1339-1347
Diketopyrrolopyrrole (DPP)‐based terpolymers—P(DPP‐TPyT) and P(DPP‐T3MTT)—bearing bithiophene donating groups and weak accepting units such as pyridine (Py) or methyl thiophene‐3‐carboxylate (3MT), in the polymer backbone, were successfully synthesized. Although the two polymers had similar physical and electrochemical properties, grazing incidence X‐ray diffraction patterns of P(DPP‐TPyT) and P(DPP‐T3MTT) showed mixed and edge‐on orientations, respectively, in thermally annealed films. Accordingly, the P(DPP‐T3MTT) showed twice the hole mobility of P(DPP‐TPyT) in a thin‐film transistor, and a blended film of P(DPP‐T3MTT) and [6,6]‐phenyl‐C71‐butyric acid methyl ester (PC71BM) showed better power conversion efficiency in a polymer solar cell. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 1339‐1347 相似文献