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Single-Crystalline Organoiridium Complex for Gas-Triggered Chromogenic Switches and Its Applications on CO Detection and Reversible Scavenging

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Chinese Journal of Chemistry 2019年第8期37卷 763-768页

作者： Li-ying Sun yuan-yuan An Li-Li Ma ying-Feng Han Key Laboratory of Synthetic and Natural Functional Molecule Chemistry College of Chemistry and Materials ScienceNorthwest UniversityXi'anShaaxi 710127China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhouFujian 350002China

Summary of main observation and conclusion Nonporous molecular single crystals of coordinatively unsaturated 16-electron metallacycle are found to undergo highly selective-yet reversible-binding of CO over CH4,H2,N2,CO2,various volatile organic compounds and water,through binding of the molecule to its metal *** monoxide is taken up by black crystals and subsequently liberated from the corresponding orange CO adduct by reversible metal coordination,the structural evidence obtained from in situ X-ray *** single-crystallinity of the metallacycle is retained even after several *** material,when adsorbed on silica,shows remarkable sensitivity and selectivity for CO,allowing visual CO sensing in the solid *** metallacycle offer the possibility of serving as readily regenerable scavenger for removing trace CO from gas mixtures with N2.

关键词： Gas-Triggered Chromogenic Switches Applications CO Detection Reversible Scavenging

Preparation of solid acid catalyst SO4^2-/TiO2/γ-Al2O3 for esterification: A study on catalytic reaction mechanism and kinetics

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Chinese Journal of Chemical Engineering 2019年第11期27卷 2696-2704页

作者： ying yuan Wenwei Jiang Jinjin Li School of Chemical Engineering Sichuan UniversityChengdu 610065China

In this work, a series of SO4^2-/TiO2/γ-Al2O3 solid acid catalysts were synthesized by impregnation method, in which nano-TiO2 was prepared by sol–gel method, and then the nano-TiO2 sol was loaded on porous γ-Al2O3 supporter through impregnation. The structure and property of catalyst were characterized by XRD, N2-BET,SEM, TEM, XPS, NH3-TPD, Pyridine-IR and FT-IR. In addition, the catalyst of chelate bidentate coordination acid center model was established. The catalytic performance test was carried out in the esterification of n-butyl alcohol with lauric acid and the catalyst showed excellent activity. The experimental results showed that the medium strength acid sites were more dominant active sites than the strong and weak acid sites for the rapid esterification reaction. Its kinetic behaviors and activation energy were studied for the esterification under the catalytic reaction condition.

关键词： Solid acid catalyst Nano-TiO2 Esterification Kinetics

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体外受精助孕患者染色体核型特点分析

宁夏医科大学学报 2012年第8期34卷 779-782页

作者：袁莹莹赵君利刘丽成洁景万红宁夏医科大学银川750004 宁夏医科大学总医院生殖医学中心银川750004 宁夏医科大学宁夏生殖与遗传重点实验室宁夏医科大学生育力保持省部共建教育部重点实验室银川750004

目的分析体外受精助孕患者染色体多态及异常检出率及主要异常核型者的临床特征。方法回顾性分析657对体外受精-胚胎移植/卵泡浆内单精子显微注射-胚胎移植(In vitro fertilization-embryo trans-fer/Intracytoplasmic sperm injection-e... 详细信息

目的分析体外受精助孕患者染色体多态及异常检出率及主要异常核型者的临床特征。方法回顾性分析657对体外受精-胚胎移植/卵泡浆内单精子显微注射-胚胎移植(In vitro fertilization-embryo trans-fer/Intracytoplasmic sperm injection-embryo transfer,IVF-ET/ICSI-ET)治疗对象的核型,分析其多态及异常核型检出率,探讨主要异常核型与生殖异常的关系及Y染色体异常与精液质量的关系。结果 IVF/ICSI助孕患者中染色体核型多态及异常者的总检出率为8.07%。其中以Y染色体异常最常见,占8.52%,其次为1、9、16号染色体变异,占1.67%。不同多态及异常核型患者的临床特征不同。Y染色体多态及异常可影响精液质量。结论 IVF/ICSI助孕者中染色体核型多态及异常者的总检出率高于我国普通人群。染色体异常是不孕不育的重要因素之一,临床应予以重视。

关键词：染色体不孕体外受精-胚胎移植卵泡浆内单精子显微注射-胚胎移植

On the horizontal distribution of algal-bloom in Chaohu Lake and its formation process

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Acta Mechanica Sinica 2014年第5期30卷 656-666页

作者： yuan-ying Chen Qing-Quan Liu Laboratory for Mechanics in Fluid Solid Coupling System Institute of Mechanics Chinese Academy of Sciences

Based on the remote sensing images of algae, the present work analyzes the horizontal distribution characteristics of algal blooms in Chaohu Lake, China, which also reveals the frequency of algal blooms under different wind directions. Further, an unstructured-grid, three-dimensional finite-volume coastal ocean model （FVCOM） is applied to investigate the wind-induced currents and the transport pro- cess to explain the reason why algal blooms occur at the detected places. We first deduce the primary distribution of biomass from overlaid satellite images, and explain the formation mechanism by analyzing the pollution sources, and simulating the flow field and transportation process under prevailing wind over Chaohu Lake. And then, we consider the adjustment action of the wind on the corresponding day and develop a two-time scale approach to describe the whole formation process of algae horizontal distribution in Chaohu Lake. That is, on the longer time scale, i.e., during bloom season, prevailing wind determines the primary distribution of biomass by inducing the characteristic flow field; on the shorter time scale, i.e., on the day when bloom occurs, the wind force adjusts the primary distribution of biomass to form the final distribution of algal bloom.

关键词： Chaohu Lake Algal bloom Horizontal distri- bution - Wind-driven current Two-time scale process

Process optimization with consideration of uncertainties——An overview

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Chinese Journal of Chemical Engineering 2018年第8期26卷 1700-1706页

作者： ying Chen Zhihong yuan Bingzhen Chen Department of Chemical Engineering Tsinghua University

Optimization under uncertainty is a challenging topic of practical importance in the Process Systems *** the solution of an optimization problem generally exhibits high sensitivity to the parameter variations, the deterministic model which neglects the parametric uncertainties is not suitable for practical applications. This paper provides an overview of the key contributions and recent advances in the field of process optimization under uncertainty over the past ten years and discusses their advantages and limitations thoroughly. The discussion is focused on three specific research areas, namely robust optimization, stochastic programming and chance constrained programming, based on which a systematic analysis of their applications, developments and future directions are presented. It shows that the more recent trend has been to integrate different optimization methods to leverage their respective superiority and compensate for their drawbacks. Moreover, data-driven optimization, which combines mathematical programming methods and machine learning algorithms, has become an emerging and competitive tool to handle optimization problems in the presence of uncertainty based on massive historical data.

关键词： Optimization under uncertainty Robust optimization Stochastic programming Chance constrained programming Data-driven optimization

Microstructure and mechanical properties of ZE10 magnesium alloy prepared by equal channel angular pressing

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International Journal of Minerals,Metallurgy and Materials 2009年第5期16卷 559-563页

作者： ying Liu Wei Li yuan-yuan Li Department of Material Science and Engineering Jinan University Guangzhou 510632 China School of Mechanical Engineering South China University of Technology Guangzhnu 510640 China

ZE10 magnesium alloy was subjected to equal-channel angular pressing （ECAP） up to 12 passes in a die with an angle of 120° between the two channels at 250-300℃. An inhomogeneous microstructure of bimodal grains including fine grains of 1-2 μm as well as coarse grains of about 20μm was obtained after the initial 1-4 ECAP passes. The grain size became increasingly homogeneous with further ECAP processing and the grains were significantly refined to 1-2 ktm after 8 passes and further refined to 0.5-1 μm after 12 passes. The alloy＇s yield strength changed slightly but the ductility improved greatly initially up to 4-6 passes corresponding to the bimodal grain microstructure. And after the subsequent pressing of more than 8 passes, the tensile strength including yield strength improved while the elongation decreased gradually.

关键词： equal channel angular pressing magnesium alloys microstructure mechanical properties

Multivariate time delay analysis based local KPCA fault prognosis approach for nonlinear processes

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Chinese Journal of Chemical Engineering 2016年第10期24卷 1413-1422页

作者： yuan Xu ying Liu Qunxiong Zhu College of Information Science and Technology Beijing University of Chemical Technology

Currently, some fault prognosis technology occasionally has relatively unsatisfied performance especially for in- cipient faults in nonlinear processes duo to their large time delay and complex internal connection. To overcome this deficiency, multivariate time delay analysis is incorporated into the high sensitive local kernel principal component analysis. In this approach, mutual information estimation and Bayesian information criterion （BIC） are separately used to acquire the correlation degree and time delay of the process variables. Moreover, in order to achieve prediction, time series prediction by back propagation （BP） network is applied whose input is multivar- iate correlated time series other than the original time series. Then the multivariate time delayed series and future values obtained by time series prediction are combined to construct the input of local kernel principal component analysis （LKPCA） model for incipient fault prognosis. The new method has been exemplified in a sim- ple nonlinear process and the complicated Tennessee Eastman （TE） benchmark process. The results indicate that the new method has suoerioritv in the fault prognosis sensitivity over other traditional fault prognosis methods.

关键词： Fault prognosis Time delay estimation Local kernel principal component analysis

Inter-chromosomal insertions into wild-type chromosomes induced by SCRaMbLE

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Frontiers of Chemical Science and Engineering 2024年第9期18卷 125-135页

作者： Sijie Zhou Junyanrui Li Xichen Cui ying Wang ying-Jin yuan Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering(Ministry of Education) School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Frontiers Research Institute for Synthetic Biology Tianjin UniversityTianjin 300072China

Genomic rearrangements play a crucial role in shaping biological phenotypic diversity and driving species *** chromosome rearrangement and modification by LoxP-mediated evolution(SCRaMbLE)has been applied to explore large-scale genomic rearrangements,yet it has been observed that these rearrangements occur exclusively in genomic regions containing loxPsym ***,we found that SCRaMbLE of synthetic yeast harboring synthetic chromosome V and X can generate a variety of synthetic segment insertions into wild-type chromosomes,ranging from 1 to 300 ***,it was revealed that the novel insertions impacted the transcriptional level of neighboring regions and affected the production of exemplar pathway of ***,our results improve the understanding of the ability of SCRaMbLE to generate complex structural variations in nonsynthetic regions and provide a potential model to explore genomic transposable events.

关键词： genomic rearrangements synthetic yeast genome SCRaMbLE inter-chromosomal insertions synthetic biology

Stabilities of delay stochastic McKean-Vlasov equations in the G-framework

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Science China(Information Sciences) 2025年第1期68卷 255-277页

作者： Haiyan yuan Quanxin ZHU Department of Mathematics Heilongjiang Institute of Technology Key Laboratory of Computing and Stochastic Mathematics (Ministry of Education) School of Mathematics and Statistics Hunan Normal University

This article focuses on a type of stochastic Mc Kean-Vlasov equation in the G-framework(G-SMVE) and addresses the stability issue for delay stochastic Mc Kean-Vlasov equations in the G-framework(G-SMVDEs). Distribution dependence and uncertainty prevent us from directly applying the stochastic analysis method for stochastic Mc Kean-Vlasov equations(SMVEs)to G-SMVEs directly. To overcome this difficulty, we introduce definitions, including the derivative of a function with a law under the G-expectation and the Lions derivatives. Then we construct a new G-It? formula for G-SMVEs according to the G-It? formula for stochastic differential equations in the G-framework(G-SDEs) and the It? formula for SMVEs. Using the new G-It? formula and the Lyapunov functional method, we investigate the moment exponential stability and almost sure asymptotic stability of G-SMVDEs. To overcome the difficulty in obtaining the distribution dependence of the exact solution to the G-SMVDE, we introduce the empirical measure and the corresponding interacting particle system, and then prove the stability equivalence between the underlying G-SMVDE and the corresponding interacting particle system. Two examples are used to confirm our theoretical results.

关键词： delay stochastic McKean-Vlasov equations Wasserstein distance G-Brownian motion Lions derivative stability