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Advances in cyclodextrin polymers adsorbents for separation and enrichment:Classification,mechanism and applications

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Chinese Chemical Letters 2022年第1期33卷 11-21页

作者： Binfen zhao Liyan jiang Qiong Jia College of Chemistry Jilin UniversityChangchun 130012China Key Laboratory for Molecular Enzymology and Engineering of Ministry of Education School of Life SciencesJilin UniversityChangchun 130012China

Over the past few decades,supramolecular chemistry has entered the field of scientific research and attracted extensive *** supramolecular macrocycles,cyclodextrins(CDs)are widely applied in the field of adsorption due to their unique structure and *** review focuses on the important role of cyclodextrin polymers(CDPs)as adsorbents in the adsorption of different *** covers the category of CDPs adsorbents(including crosslinked CDPs,grafted CDPs,CD-based polyrotaxanes/pseudopolyrotaxanes,and imprinted CDPs),their adsorption mechanism and applications in the adsorption of inorganic metal ions,organic pollutants,and ***,the challenges and future perspectives in relative research fields are discussed.

关键词： Cyclodextrin polymer Adsorption Inorganic metal ions Organic pollutants Biomacromolecules Review

Geochemical features and genesis of the natural gas and bitumen in paleo-oil reservoirs of Nanpanjiang Basin, China

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Science China Earth Sciences 2007年第5期50卷 689-701页

作者： zhao MengJun ZHANG ShuiChang zhao Lin DA jiang Research Institute of Exploration and Development PetroChinaBeijing 100083China Guizhou Institute of Petroleum Geology Southern Petroleum Exploration and Development Corp.SinopecGuiyang 550000China

Bitumen from the Nanpanjiang Basin occurs mainly in the Middle Devonian and Upper Permian reef limestone paleo-oil reservoirs and reserves primarily in holes and fractures and secondarily in minor matrix pores and bio-cavities. N2 is the main component of the natural gas and is often associated with pyrobitumen in paleo-oil reservoirs. The present study shows that the bitumen in paleo-oil reservoirs was sourced from the Middle Devonian argillaceous source rock and belongs to pyrobitumen by crude oil cracking under high temperature and pressure. But the natural gas with high content of N2 is neither an oil-cracked gas nor a coal-formed gas generated from the Upper Permian Longtan Formation source rock, instead it is a kerogen-cracked gas generated at the late stage from the Middle Devonian argilla- ceous source rock. The crude oil in paleo-oil reservoirs completely cracked into pyrobitumen and methane gas by the agency of hugely thick Triassic deposits. After that, the abnormal high pressure of methane gas reservoirs was completely destroyed due to the erosion of 2000--4500-m-thick Triassic strata. But the kerogen-cracked gas with normal pressure was preserved under the relatively sealed condition and became the main body of the gas shows.

关键词： source rocks paleo-oil reservoir pyrobitumen kerogen-cracked gas Nanpanjiang Basin

Recent progress on the activation of the cGAS–STING pathway and its regulation by biomolecular condensation

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Journal of Molecular Cell Biology 2022年第6期14卷 1-13页

作者： Xiaoyu Yu Zhen zhao Zhengfan jiang Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education School of Life SciencesPeking UniversityBeĳing 100871China Peking-Tsinghua Center for Life Sciences Peking UniversityBeĳing 100871China

The cyclic guanosine monophosphate (GMP)–adenosine monophosphate (AMP) synthetase (cGAS)–stimulator of interferon genes(STING) pathway, comprising the DNA sensor cGAS, the second messenger cyclic GMP–AMP (cGAMP), and the endoplasmicreticulum (er) adaptor protein STING, detects cytoplasmic double-stranded DNA (dsDNA) to trigger type I-interferon responses forhost defense against pathogens. Previous studies defined a model for the allosteric activation of cGAS by DNA-binding, but recentwork reveals other layers of mechanisms to regulate cGAS activation such as the phase condensation and metal ions, especially thediscovery of Mn^(2+) as a cGAS activator. Activation of the 23-cGAMP sensor STING requires translocating from the er to the Golgiapparatus. The sulfated glycosaminoglycans at the Golgi are found to be the second STING ligand promoting STING oligomerizationand activation in addition to 23-cGAMP, while surpassed levels of 23-cGAMP induce er-located STING to form a highly organizeder membranous condensate named STING phase-separator to restrain STING activation. Here, we summarize recent advances in theregulation of cGAS–STING activation and their implications in physiological or pathological conditions, particularly focusing on theemerging complexity of the regulation.

关键词： innate immunity cGAS-STING cGAMP manganese(Mn2+) sulfated glycosaminoglycans(sGAGs) biomolecular condensate STING phase-separator

Key Parameters Analysis and Regulation of Singlet Oxygen Quenching Rate of Carotenoids

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Chinese Journal of Structural Chemistry 2020年第7期39卷 1226-1234页

作者： zhao Kai jiang Wei MENG Chong Education Academy Beijing Sport UniversityBeijing 100084China School of Environment Beijing Normal UniversityBeijing 100875China

28 kinds of carotenoids are studied to reveal the key parameters and regulation on the singlet oxygen quenching ***,the quantum chemistry parameters of carotenoids calculated by Gaussian software combined with substitution parameters were used to construct the quantitative structure-activity relationship model(QSAR)of the singlet oxygen quenching rate of *** key parameters affecting the antioxidant activity of carotenoids are revealed,and the data predicted via the QSAR model were provided for subsequent ***,a three-dimensional(3D)pharmacophore model was used to regulate and modify the antioxidant activity of *** correlation coefficients of the modeling group(R2)and verification group(Rpre2)of the established QSAR model were 0.945 and 0.916,respectively,which can be used for the analysis of antioxidant activity of carotenoids;the antioxidant activity of carotenoids can be significantly regulated by the number of conjugated C=C bonds,the energy difference between frontier molecular orbitals and the partial Mulliken charge in C1 and theπ···π*excitation energy E(s);the antioxidant activity of carotenoids can be effectively regulated by the hydrogen bond acceptor pharmacophores on both sides of the conjugated C=C bonds and the hydrophobic groups on the conjugated C=C bond;the hydrophobic substituents attached to conjugated C=C bonds can effectively improve the singlet oxygen quenching rate of carotenoids.

关键词： carotenoids singlet oxygen quenching quantitative structure-activity relationship model 3D pharmacophore model parameters analysis

Numerical Optimization on Aerodynamic/Stealth Characteristics of Airfoil Based on CFD/CEM Coupling Method

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Transactions of Nanjing University of Aeronautics and Astronautics 2016年第3期33卷 274-284页

作者： jiang Xiangwen zhao Qijun zhao Guoqing Meng Chen National Key Laboratory of Science and Technology on Rotorcraft Aeromechanics Nanjing University of Aeronautics and Astronautics

Based on computational fluid dynamics （CFD）/computational eleetromagnetics method （CEM） coupling method and surrogate model optimization techniques, an integration design method about aerodynamic/stealth characteristics of airfoil is established. The O-type body-fitted and orthogonal grid around airfoil is first generated by using the Poisson equations, in which the points per wave and the normal range satisfy the aerodynamic and electromagnetic calculation accuracy requirement. Then the aerodynamic performance of airfoil is calculated by sol- ving the Navier-Stokes （N-S） equations with Baldwin-Lomax （B-L） turbulence model. The stealth characteristics of airfoil are simulated by using finite volume time domain （FVTD） method based on the Maxwell＇s equations, Steger-Warming flux splitting and the third-order MUSCL scheme. In addition, based upon the surrogate model optimization technique with full factorial design （FFD） and radial basis function （RBF）, an integration design about aerodynamic/stealth characteristics of rotor airfoil is conducted by employing the CFD/CEM coupling meth- od. The aerodynamic/stealth characteristics of NACA series airfoils with different maximum thickness and camber combinations are discussed. Finally, by choosing suitable lift-to-drag ratio and radar cross section （RCS） ampli- tudes of rotor airfoil in four important scattering regions as the objective function and constraint, the compromised airfoil with high lift-to-drag ratio and low scattering characteristics is designed via systemic and comprehensive ana- lyses.

关键词： rotor airfoil aerodynamic characteristics stealth characteristics CFD/CEM coupling surrogate modle

A criterion on a repeller being a null set of any limit measure for stochastic differential equations

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Science China Mathematics 2021年第2期64卷 221-238页

作者： Lifeng Chen zhao Dong Jifa jiang Mathematics and Science College Shanghai Normal UniversityShanghai 200234China RCSDS Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China

This paper studies limit behaviors of stationary measures for stochastic ordinary differential equations with nondegenerate noise and presents a criterion to guarantee that a repeller with zero Lebesgue measure is a null set of any limit *** this criterion,we first provide a series of nontrivial concrete examples to show that their repelling limit cycles or quasi-periodic orbits are null sets for all limit measures,which deduces that all their limit measures are concentrated on stable equilibria and stable limit cycles or quasi-periodic orbits,and *** open questions on exact supports of limit measures are proposed.

关键词： stationary measure limit measure support Lyapunov function repelling limit cycle repelling quasi-periodic orbit

Stereoselective Ring-Opening Polymerization of rac-Lactide Catalyzed by Squaramide Derived Organocatalysts at Room Temperature

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Chinese Journal of Chemistry 2021年第9期39卷 2403-2409页

作者： Xiao jiang Na zhao Zhibo Li Key Laboratory of Biobased Polymer Materials Shandong Provincial Education DepartmentCollege of Polymer Science and EngineeringQingdao University of Science and TechnologyQingdaoShandong 266042China College of Chemical Engineering Qingdao University of Science and TechnologyQingdaoShandong 266042China

Substa ntial progresses have bee n made toward the developme nt of meta I-free catalysts for stereoselective rin g-ope ning polymeriza-tion(ROP)of *** the discovery of organic catalysts effective at ambient temperature remains a major ***,the bifunctional H-bonding catalyst SQ-1 containing a basic tertiary amine and squaramide motif proved to be good candidate for the stereoselective ROP of rac-lactide at room temperature,yielding stereoregular polylactide with controlled molecular weights(up to 21.1 kg/mol)and high tacticity(PjESC up to 0.88).Furthermore,binary H-b on ding catalytic system con sisti ng of squaramides(SQ-2 to SQ-6)and 1,8-diazabicyclo[5.4.0]undec-7-ene(DBU)could efficiently promote the ROP of rac-lactide at room temperature within short reaction *** them,the most bulky squaramide SQ-2 exhibited the best steroselectivity towards the ROP of rac-lactide without transesterification side reactions during the polymerization *** resulting polylactides were proved to have controlled molecular weights as high as 22.2 kg/mol and narrow distributions(1.10-1.24).

关键词： Ring-opening polymerization Organocatalysis Squaramide Polymers Stereoselective

A class of fully third-order accurate projection methods for solving the incompressible Navier-Stokes equations

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Acta Mechanica Sinica 2005年第6期21卷 542-549页

作者： Yuxin Ren Yuxi jiang Miao'er Liu Hanxin Zhang Department of Engineering Mechanics Tsinghua University Beijing 100084 China CNOOC Research Center Beijing China National Key Laboratory for CFD Beijing China

In this paper, a fully third-order accurate projection method for solving the incompressible Navier-Stokes equations is proposed. To construct the scheme, a continuous projection procedure is firstly presented. We then derive a sufficient condition for the continuous projection equations to be temporally third-order accurate approximations of the original Navier-Stokes equations by means of the localtruncation-error-analysis technique. The continuous projection equations are discretized temporally and spatially to third-order accuracy on the staggered grids, resulting in a fully third-order discrete projection scheme. The possibility to design higher-order projection methods is thus demonstrated in the present paper. A heuristic stability analysis is performed on this projection method showing the probability of its being stable. The stability of the present scheme is further verified through numerical tests. The third-order accuracy of the present projection method is validated by several numerical test cases.

关键词： Incompressible Navier-Stokes equations Projection methods - Third-order scheme - Local truncation error

On a General Class of Semiparametric Hazards Regression Models for Recurrent Gap Times

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Acta Mathematicae Applicatae Sinica 2019年第3期35卷 549-563页

作者： Qin jiang Hui zhao Hong QIN Department of Statistics Central China Normal UniversityWuhan 430079China Department of Mathematics Huanggang Normal UniversityHuanggang 438000China Department of Statistics Zhongnan University of Economics and LawWuhan 430073China

In the article,we investigate a general class of semiparametric hazards regression models for recurrent gap *** general class includes the proportional hazards model,the accelerated failure time model and the accelerated hazards models as special *** model is flexible in modelling recurrent gap times since a covariate effect is identified as having two separate components,namely a time-scale change on hazard progression and a relative hazards *** order to infer the model parameters,the procedure is proposed based on estimating *** asymptotic properties of the proposed estimators are established and the finite sample properties are investigated via simulation *** addition,a lack of fit test is presented to assess the adequacy of the model and an application of data from a bladder cancer study is reported for illustration.

关键词： gap times model checking recurrent events estimating equations semiparametric model