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On the nonclassical dynamics of cavity-assisted four-channel nonlinear coupler

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Chinese Physics B 2018年第11期27卷 498-505页

作者： Rafael julius Abdel-Baset M A Ibrahim Pankaj Kumar Choudhury Hichem Eleuch Faculty of Applied Sciences Universiti Teknologi MARA (UiTM) Faculty of Applied Sciences Universiti Teknologi Mara (UiTM) Perak Tapah Campus Institute of Microengineering and Nanoelectronics Universiti Kebangsaan Malaysia Department of Applied Sciences and Mathematics College of Arts and Sciences Abu Dhabi University Institute for Quantum Science and Engineering Texas A&M University College Station

The non-classical properties of light propagating in four-channel Kerr waveguides, confined in an optical cavity, are studied. The solution to the Hamiltonian of field operators is obtained semi-analytically by using symmetrically ordered phase-space representation. Full quantum analysis of the input coherent fields displays a strong transition of photon property between the super-Poissonian and sub-Poissonian statistics. It is found that the cavity-assisted multichannel system exhibits enhanced squeezing both in single-and compound-mode. This multichannel system may be utilized as an efficient quantumlight generator.

关键词： squeezed states Kerr effects Langevin equation

Improved dark ambient degradation of organic pollutants by cerium strontium cobalt perovskite

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Journal of Environmental Sciences 2020年第4期32卷 110-118页

作者： Huihuang Chen julius Motuzas Wayde Martens Joao C.Diniz da Costa The University of Queensland FIM^2 Lab-Functional Interfacial Materials and Membranes LaboratorySchool of Chemical EngineeringBrisbaneQld 4072Australia Hefei National Laboratory for Physical Sciences at the Microscale University of Science and Technology of ChinaAnhui 230026China Science and Engineering Faculty Queensland University of TechnologyBrisbaneQld 4000Australia LAQV-REQUIMTE (Bio)Chemical Process EngineeringDepartment of ChemistryFaculty of Science and TechnologyUniversidade NOVA de LisboaCaparica 2829-516Portugal

This work investigates the effect of cerium substation into strontium cobalt perovskites(CeSrCoO)for the oxidative degradation of OrangeⅡ(OII)in dark ambient conditions without the aid of any external stimulants such as light,heating or chemical *** OII degradation rate by CeSrCoO reached 65%in the first hour,whilst for the blank sample without cerium(SrCoO)took over 2 hr to reach the same level of OII ***,the cerium substitution improved the catalytic activity of the perovskite material,mainly associated with the Ce0.1Sr0.9CoO3 perovskite *** contacting CeSrCoO,the-N=Nazo bonds of the OII molecules broke down resulting in electron donation and the formation of *** electrons are injected into the CeSrCoO and resulted in a redox pair of Co3+/Co2+,establishing a bridge for the electron transfer between OII and the ***,the electrons also formed reactive species(·OH)responsible for OII degradation as evidenced by radical trapping *** species were formed via the reaction between 02 and donated electrons from OII with the aid of cobalt redox *** the prepared materials dispensed with the need for light irradiation and additional oxidants,it opens a window of environmental applications for treating contaminated wastewaters.

关键词： Dark catalysis Acid orange degradation Cerium substituted perovskite Catalytic activity

Bioprospecting optimal phenology for bioactive molecules in native golden yellow Pleurotus citrinopileatus Singer

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Asian Pacific Journal of Tropical Biomedicine 2016年第2期6卷 132-142页

作者： Godfrey Nattoh Erastus Gatebe Fredrick Musieba julius Mathara Department of Molecular Biology and Biotechnology Pan African University Institute for Basic SciencesTechnology and Innovation Research Technology and Innovation Department Kenya Industrial Research and Development Institute Department of Chemistry Jomo Kenyatta University of Agriculture Science and Technology Department of Food Science and Technology Jomo Kenyatta University of Agriculture Science and Technology

Objective: To bioprospect optimal phenological phases as source of novel molecules from native golden yellow Pleurotus citrinopileatus across four phenologies in both aqueous and ethanol extracts, and identify novel molecules responsible for these ***: Standard qualitative assay, Folin–Ciocalteu assay; aluminium chloride spectrophotometric, 2, 2-diphenyl-1-picrylhydrazyl, 2, 20-azinobis(3-ethylbenzothiazoline-6-suslfonic acid, ferricyanide reducing antioxidant power were used to determine total flavonoid, polyphenols, radical scavenging, and reducing power. Spectrophotometric methods were used for lycopene, b-carotene, and total carotenoids, while liquid chromatography quadrupole time of flight mass spectrometry was used for identification and comparative quantitation of polyphenols and flavonoids across the four phenological states. Chem Spider? database was used for the identification of compounds based on their empirical formula, accurate mass and literature review of previously reported compounds in ***: Primordial phases exhibited higher contents of secondary metabolites than mature basidiocarps. Polyphenols content differed across physiological phases with primordials exhibiting significant high contents(P < 0.05) [(13.803 ± 0.797) mg gallic acid equivalent/g dry weight]. Distribution of total flavonoids was significantly different(P < 0.05) across physiological states and ranged from(3.311 ± 0.730) to(14.824 ± 0.890) mg quercetin equivalent g dry weight. Ten polyphenol acids and seven flavonoids compounds identified varied across these phases with primordials exhibiting relatively high peak areas. Total antioxidant activities showed a positive correlation with total polyphenols(r = 0.969;P < 0.05) and total flavonoids(r = 0.960; P < 0.05) across these ***: These findings provide evidence that primordials of golden yellow mushroom as opposed to their fruiting bodies are potent sources of bioactive health molecule

关键词： Bioprospecting Primordial Phenology Bioactive molecules Liquid chromatography-quadrupole time of flight mass spectrometry Edible fungi

A Multiple Particle Swarm Optimization Algorithm and Its Application in PID Parameters Tuning

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A Multiple Particle Swarm Optimization Algorithm and Its App...

作者： julius NIYONGABO 湖南大学

学位级别：硕士

在技术流程工业,控制过程是主要的课题。为了环境问题和正在审理的产品质量,在工业上去保持流程工作可能性和安全性是非常重要的。为从小工业到高技术产业的过程控制,大多数采用PID控制器。PID控制算法,是一种更健壮的较容易理解的算法... 详细信息

在技术流程工业,控制过程是主要的课题。为了环境问题和正在审理的产品质量,在工业上去保持流程工作可能性和安全性是非常重要的。为从小工业到高技术产业的过程控制,大多数采用PID控制器。PID控制算法,是一种更健壮的较容易理解的算法,它能提供好的控制性能,尽管不同的动态特性的过程。然而,为了PID控制器的工作有可能,已选择的PID控制器参数必须被调整。因此,我们如何优化PID控制器参数?我们还可以采用由Ziegler-Nichols提出的传统的技术来搜索最优PID控制器参数吗?还是我们需要用新的方法用随机的方式来调整PID? 在这个项目中,我们提出使用多粒子群算法（MPSO）,来调整PID控制器参数。MPSO是一种最优化的方法。在探索搜索空间的不同的方法中,超启发式优化被认为是高水平的策略方法,它是一个新家庭的随机算法来解决棘手的优化问题。它可分为两大类,其中被认为是单一的解决方案,而在众多的解决方案进化并发执行。用来解决各种应用问题,许多研究人员已经证明了这一技术在大量优化问题上的效率。在这一家庭的随机算法,粒子群算法（PSO）算法,是最强大的metaheuristic开发,过去十年中,用来发现全球优化问题在搜索空间。这个灵感是来自于从社会行为的动物生活在群,如鸟植绒或鱼的教育。蜂群的粒子使用直接的交流方式,以建立解决非线性问题,基于他们的集体经验。被广泛使用,粒子群优化算法迅速发展为它容易实施和一些粒子需要调整。它是一种有效的多尺度,线性及非线性问题。最近,研究显示,粒子群优化算法已成功的应用来解决PID参数优化问题。在这项研究中,目标是提高粒子群优化算法的寻优能力,来确定最优PID控制器参数,通过执行与多群相结合的一个新的超启发式优化算法。该方法结合许多带颗粒的群,以便交换它们最佳位置信息,基于他们的集体经验,从而建立一个解决非线性问题的方法因此,利用粒子群优化算法的PID控制器被设计出来之后,同样的模型再使用MPSO算法被重新设计。这些设计的控制器分别被叫做PSO-PID控制器和MPSO控制器。用Matlab编程语言来对这两种设计的仿真结果表明,我们的方法能有效的寻找最佳的PID控制器参数。与标准的PSO-PID控制器相比,该控制器是更有效率,例如,在提高阶跃响应特性,减少了错误,上升时间、调整时间和超调方面。

关键词：最优化超启发式粒子群算法 PID控制器 MPSO-PID控制器

O_(2)在不同终端Fe_(31)MnC(001)表面吸附与解离的理论研究

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稀有金属材料与工程 2022年第12期51卷 4527-4532页

作者：牛雪莲 julius Jellinek 大连海洋大学海洋科技与环境学院辽宁大连116023 美国阿贡国家实验室伊利诺伊州60439

采用密度泛函理论中的广义梯度近似方法(GGA)研究了氧分子在Fe_(31)MnC(001)表面的3种不同吸附位(顶位、桥位和面心间位)的吸附行为和C对Fe_(31)Mn磁性的影响。通过吸附能结果发现,氧分子倾向于垂直吸附在四配位饱和的空穴位,而氧原子... 详细信息

采用密度泛函理论中的广义梯度近似方法(GGA)研究了氧分子在Fe_(31)MnC(001)表面的3种不同吸附位(顶位、桥位和面心间位)的吸附行为和C对Fe_(31)Mn磁性的影响。通过吸附能结果发现,氧分子倾向于垂直吸附在四配位饱和的空穴位,而氧原子强烈吸附在相邻的四配位空穴中。以Mn为表层原子的表面均发生了氧分子的解离吸附,桥位吸附对应的吸附结构最稳定。C原子增加了基体的磁化强度杂化,抑制近邻Fe和Mn原子之间的反铁磁相互作用。

关键词：钢第一性原理吸附解离磁性

Attention-Based and Time Series Models for Short-Term Forecasting of COVID-19 Spread

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Computers, Materials & Continua 2022年第1期70卷 695-714页

作者： Jurgita Markeviciute Jolita Bernataviciene Ruta Levuliene Viktor Medvedev Povilas Treigys julius Venskus Institute of Applied Mathematics Vilnius UniversityVilnius03225Lithuania Institute of Data Science and Digital Technologies Vilnius UniversityVilnius08412Lithuania

The growing number of COVID-19 cases puts pressure on healthcare services and public institutions *** pandemic has brought much uncertainty to the global economy and the situation in *** methods and modeling techniques are important tools for governments to manage critical situations caused by pandemics,which have negative impact on public *** main purpose of this study is to obtain short-term forecasts of disease epidemiology that could be useful for policymakers and public institutions to make necessary short-term *** evaluate the effectiveness of the proposed attention-based method combining certain data mining algorithms and the classical ARIMA model for short-term forecasts,data on the spread of the COVID-19 virus in Lithuania is used,the forecasts of epidemic dynamics were examined,and the results were presented in the ***,the approach presented might be applied to any country and other pandemic *** COVID-19 outbreak started at different times in different countries,hence some countries have a longer history of the disease with more historical data than *** paper proposes a novel approach to data registration and machine learning-based analysis using data from attention-based countries for forecast validation to predict trends of the spread of COVID-19 and assess risks.

关键词： COVID-19 spread modeling attention-based forecasting machine learning data registration data analysis ARIMA

Artificial neural network model for predicting drill cuttings settling velocity

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Petroleum 2020年第4期6卷 340-352页

作者： Okorie E.Agwu julius U.Akpabio Adewale Dosunmu Department of Chemical and Petroleum Engineering University of UyoAkwa Ibom StateNigeria Department of Petroleum and Gas Engineering University of PortHarcourtRivers StateNigeria

The traditional method of using the coefficient of drag–Reynolds number relationship to predict cuttings settling velocity involves an implicit procedure that requires repeated,time-consuming and tedious iterations using Newtonian or mostly non-Newtonian ***,these correlations are limited to certain fluid flow ***,most of the explicit and direct cuttings settling velocity models that exist are based on the assumption that the cuttings are spherical ***,in the field,the cuttings are a mixture of various shapes and are hardly spherical,hence these models when applied to field conditions come off with huge *** objective of this work was to use a nature-inspired algorithm(artificial neural network-ANN)to develop a model for estimating cuttings settling velocity that would be robust and useful in the field that would take into account the shape of the *** data used for this work was obtained from research experiments in the *** model was then evaluated using four performance metrics namely:mean squared error(MSE),root mean square error(RMSE),sum of squares error(SSE)and goodness of fit(R2).It was found that the model's predictions obtained in this work agreed with experimental ***,the developed model possesses the capacity to generalize across new input datasets and can be applied to particles of any shape,hence,defining the novelty of this research and bridging the gap between theory and *** compared with state-of-the-art models,the developed models show a high degree of robustness,as the ANN model performed reasonably well with an MSE of 7.5×10−4,an R2 of 0.978,RMSE of 0.0274 and SSE of *** generalize the results across new input datasets,the developed model was cross-validated with new data that was not part of the training *** was found that the ANN model had an MSE value 0.00807,RMSE of 0.0898,MAE of 0.065,SSE of 2.74 and MAPE of 0.675%.To ensure the replicabi

关键词： Drill cuttings Artificial neural network Mud Cuttings settling velocity

Metal coordination to a deep cavitand promotes binding selectivities in water

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Chinese Chemical Letters 2022年第11期33卷 4908-4911页

作者： Yong-Qing Chen Hua-Wei Guan Kuppusamy Kanagaraj julius Rebek Yang Yu Center for Supramolecular Chemistry and Catalysis and Department of Chemistry College of ScienceShanghai UniversityShanghai 200444China Skaggs Institute for Chemical Biology and Department of Chemistry The Scripps Research InstituteLa JollaCA 92037United States

One goal of supramolecular chemistry is the creation of synthetic receptors that have a high affinity for hydrophilic molecules in *** found that cavitands with upper rims extended by pyridyl groups coax hydrophilic guests into the cavity where they are shielded from the aqueous *** ability of Pd(Ⅱ)to coordinate adjacent pyridyl groups leads to increased selectivity for highly hydrophilic solvent molecules such as acetone,1,4-dioxane and tetrahydrofuran in *** of the binding behavior indicated that metal-coordination restricts the container entrance,shrinks the effective cavity volume and increases the energetic barrier to guest exchange.

关键词： Host-guest chemistry Metallo cavitand Hydrophilic small molecules Molecular recognition Water-soluble containers

Shape Selectivity of a Metallo Cavitand Host Allows Separation of n-Alkanes from Isooctane

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Chinese Journal of Chemistry 2021年第6期39卷 1498-1502页

作者： Yun-Hui Wan Faiz-Ur Rahman julius Rebek Jr. Yang Yu Center for Supramolecular Chemistry&Catalysis and Department of Chemistry College of ScienceShanghai University99 Shang-Da RoodShanghai 200444China Skaggs Institute for Chemical Biology and Department of Chemistry The Scripps Research Institute10550 North Torrey Pines Roadio JolloCA 92037USA

The use of a metallo cavitand for the selective sequestration of n-alkanes from their mixtures with isooctane is *** experiments and NMR spectroscopy are used to show the preference of a water-soluble cavitand host for guests that are hydro-phobic and have narrow or flat *** host showed selectivity for trans 1,4-dimethylcyclohexane over the *** sep-arations of n-alkanes from isooctane by gas/liquid adsorption and a liquid/liquid extraction are detailed.

关键词： Metallo cavitand Shape selectivity eceptor Alkane separation Host-guest system