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Tandem hydroalkylation and deoxygenation of lignin-derived phenolics to synthesize high-density fuels

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Chinese Journal of Chemical Engineering 2024年第2期66卷 104-109页

作者： Rui yu zhensheng Shen Yanan Liu Chengxiang Shi Juncong Qu Lun Pan Zhenfeng Huang Xiangwen Zhan g Ji-Jun Zou Key Laboratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Collaborative Innovative Center of Chemical Science and Engineering(Tianjin) Tianjin 300072China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China

Lignin is the most abundant naturally phenolic biomass,and the synthesis of high-performance renewable fuel from lignin has attracted significant attention.We propose the efficient synthesis of high-density fuels using simulated lignin cracked oil in tandem with hydroalkylation and deoxygenation reactions.First,we investigated the reaction pathway for the hydroalkylation of phenol,which competes with the hydrodeoxygenation form cyclohexane.And then,we investigated the effects of metal catalyst types,the loading amount of metallic,acid dosage,and reactant ratio on the reaction results.The phenol hydroalkylation and hydrodeoxygenation were balanced when 180℃ and 5 MPa H_(2)with the alkanes yield of 95%.By extending the substrate to other lignin-derived phenolics and simulated lignin cracked oil,we obtained the polycyclic alkane fuel with high density of 0.918 g·ml^(-1)and calorific value of41.2 MJ·L^(-1).Besides,the fuel has good low-temperature properties(viscosity of 9.3 mm^(2)·s^(-1)at 20℃ and freezing point below-55℃),which is expected to be used as jet fuel.This work provides a promising way for the easy and green production of high-density fuel directly from real lignin oil.

关键词： High-density fuel Biofuel Hydrogenation Alkylation Lignin Phenolics

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求解一类二次规划反问题的同伦交替方向法

上海理工大学学报 2022年第3期44卷 281-287页

作者：高峰宇振盛上海理工大学理学院上海200093

对一类带不等式约束的二次规划反问题的求解方法进行研究。首先表示出此类二次规划对应的反问题形式,将该反问题转化为目标函数变量可分离优化问题,将其中约束写成KKT条件的形式之后,该反问题等同于一个等式约束优化问题。综合以上,考... 详细信息

对一类带不等式约束的二次规划反问题的求解方法进行研究。首先表示出此类二次规划对应的反问题形式,将该反问题转化为目标函数变量可分离优化问题,将其中约束写成KKT条件的形式之后,该反问题等同于一个等式约束优化问题。综合以上,考虑使用交替方向乘子法进行迭代,在此基础之上,将同伦思想应用于算法每步迭代的子问题中,以此避免近端算子选取的敏感性,又可保证算法的收敛速度。针对子问题,使用逐次超松弛法进行求解,并获取算法的收敛性。最后,将该算法与SDPT3和Sedumi两种方法进行比较,数值结果表明,该算法无论在速度上还是效率上都优于以上两种方法。

关键词：反问题二次规划同伦交替方向法超松弛迭代法

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多面体约束非光滑复合函数的序列有效集方法

上海理工大学学报 2022年第4期44卷 373-380页

作者：时闪闪宇振盛上海理工大学理学院上海200093

对带多面体约束的非光滑复合函数问题的求解进行了研究。针对非光滑复合函数问题,首先,构造光滑函数来逼近非光滑目标函数,通过求解光滑近似问题来达到求解原问题的目的。在此基础上,考虑多面体约束的特殊结构,运用序列二次规划算法的思... 详细信息

对带多面体约束的非光滑复合函数问题的求解进行了研究。针对非光滑复合函数问题,首先,构造光滑函数来逼近非光滑目标函数,通过求解光滑近似问题来达到求解原问题的目的。在此基础上,考虑多面体约束的特殊结构,运用序列二次规划算法的思想,利用有效集策略,通过逐次求解一系列仅含等式约束的二次规划问题来逼近搜索方向的最优解,再通过线搜索求得步长,进而得到下一步的迭代点。最后,从理论上证明了算法的全局收敛性,并进行了初步的数值实验。将该算法与光滑序列投影收缩算法作对比,结果表明,该算法在迭代次数和计算时间上都有一定的优势。

关键词：光滑近似多面体约束复合函数序列二次规划有效集

On the Solution of the Eigenvalue Complementarity Problem by a Line Search Filter-SQP Algorithm

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Journal of Applied Mathematics and Physics 2017年第10期5卷 1986-1996页

作者： Qiu yu zhensheng yu Yangchen Liu University of Shanghai for Science and Technology Shanghai China

In this paper, the Eigenvalue Complementarity Problem (EiCP) with real symmetric matrices is addressed, which appears in the study of contact problem in mechanics. We discuss a quadratic programming formulation to the... 详细信息

关键词： Eigenvalue Complementarity Problem Nonlinear Programming Line Search Filter Method

Sparse Solutions of Mixed Complementarity Problems

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Journal of Applied Mathematics and Physics 2020年第1期8卷 10-22页

作者： Peng Zhang zhensheng yu College of Science University of Shanghai for Science and Technology Shanghai China

In this paper, we consider an extragradient thresholding algorithm for finding the sparse solution of mixed complementarity problems (MCPs). We establish a relaxation l1 regularized projection minimization model for the original problem and design an extragradient thresholding algorithm (ETA) to solve the regularized model. Furthermore, we prove that any cluster point of the sequence generated by ETA is a solution of MCP. Finally, numerical experiments show that the ETA algorithm can effectively solve the l1 regularized projection minimization model and obtain the sparse solution of the mixed complementarity problem.

关键词： Mixed Complementarity Problem Sparse Solution l1 Regularized Projection Minimization Model Extragradient Thresholding Algorithm

An Alternating Direction Nonmonotone Approximate Newton Algorithm for Inverse Problems

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Journal of Applied Mathematics and Physics 2016年第11期4卷 2069-2078页

作者： Zhuhan Zhang zhensheng yu Xinyue Gan University of Shanghai for Science and Technology Shanghai China

In this paper, an alternating direction nonmonotone approximate Newton algorithm (ADNAN) based on nonmonotone line search is developed for solving inverse problems. It is shown that ADNAN converges to a solution of th... 详细信息

关键词： Nonmonotone Line Search Alternating Direction Method Bound-Constraints Newton Method

A Smoothing Neural Network Algorithm for Absolute Value Equations

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Engineering（科研） 2015年第9期7卷 567-576页

作者： Feiran Wang zhensheng yu Chang Gao College of Science University of Shanghai for Science and Technology Shanghai

In this paper, we give a smoothing neural network algorithm for absolute value equations (AVE). By using smoothing function, we reformulate the AVE as a differentiable unconstrained optimization and we establish a steep descent method to solve it. We prove the stability and the equilibrium state of the neural network to be a solution of the AVE. The numerical tests show the efficient of the proposed algorithm.

关键词： Absolute Value Equations Neural Network Smoothing Function Linear Complementarity Problem

A Continuous Approach to Binary Quadratic Problems

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Journal of Applied Mathematics and Physics 2018年第8期6卷 1720-1732页

作者： Zhi Liu zhensheng yu yunlong Wang College of Science University of Shanghai for Science and Technology Shanghai China

This paper presents a continuous method for solving binary quadratic programming problems. First, the original problem is converted into an equivalent continuous optimization problem by using NCP (Nonlinear Complementarity Problem) function, which can be further carry on the smoothing processing by aggregate function. Therefore, the original combinatorial optimization problem could be transformed into a general differential nonlinear programming problem, which can be solved by mature optimization technique. Through some numerical experiments, the applicability, robustness, and solution quality of the approach are proved, which could be applied to large scale problems.

关键词： Binary Quadratic Program Continuous Approach NCP Function Nonlinear Programming Aggregate Function Multiplier Penalty Function

Spectral Gradient Algorithm Based on the Generalized Fiser-Burmeister Function for Sparse Solutions of LCPS

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Open Journal of Statistics 2015年第6期5卷 543-551页

作者： Chang Gao zhensheng yu Feiran Wang College of Science University of Shanghai for Science and Technology Shanghai China

This paper considers the computation of sparse solutions of the linear complementarity problems LCP(q, M). Mathematically, the underlying model is NP-hard in general. Thus an lp(0 p < 1) regularized minimization model is proposed for relaxation. We establish the equivalent unconstrained minimization reformation of the NCP-function. Based on the generalized Fiser-Burmeister function, a sequential smoothing spectral gradient method is proposed to solve the equivalent problem. Numerical results are given to show the efficiency of the proposed method.

关键词： Linear Complementarity Problem Sparse Solution Spectral Gradient Generalized Fischer-Burmeister