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Chinese Chemical Letters 2014年第12期25卷 1550-1554页

作者： Meng-Juan Liab Yan-Hong Huangb An-Qi Jub Tian-Shi Yub ming-qiao geab Key Laboratory of Eco-Textiles(Jiangnan University) Ministry of Education College of Textile  Clothing Jiangnan University

This work aimed at effectively utilizing the chemically depolymerized waste poly（ethylene terephthalate）（PET） fibers into useful products for the textile *** fibers were glycolytically degraded by excess ethylene glycol as depolymerizing agent and zinc acetate dihydrate as *** glycolysis product,bis（2-hydroxyethyl） terephthalate（BHET）,was purified through repeated crystallization to get an average yield above 80%.Then,BHET was nitrated,reduced,and azotized to get diazonium ***,the produced diazonium salt was coupled with 1-（4-sulfophenyl）-3-methyl-5-pyrazolone to get azo *** structures of BHET and azo dyestuff were identified by FT1 R and ^1H NMR spectra and elemental *** filaments dyed by the synthesized azo dyestuff with the dye bath pH from 4.14 to 5.88 showed bright yellow *** performances of the dyestuff were described with dye uptake,color fastness,K/S,L^＊,a^＊,b^＊.and △E^＊ values.

关键词： Waste PET fibers Depolymerization Bis(2-hydroxyethyl) terephthalate Azo dyestuff

A silylene-stabilized distannavinylidene with a highly labile substituent

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Science China Chemistry 2023年第12期66卷 3555-3561页

作者： Zihao qiao ming Chen Zhenbo Mo State Key Laboratory and Institute of Elemento-Organic Chemistry Frontiers Science Center for New Organic MatterCollege of ChemistryNankai UniversityTianjin 300071China

Vinylidene and its heavier analogues are fundamentally important in synthetic chemistry,but their stabilization and structural characterization remains extremely *** we describe that the reduction of an NHSi-stabilized stannyl-stannylene(2)with one molar equivalent of[(^(Mes)Nacnac)Mg]_(2)affords an NHSi-stabilized distannavinylidene(3).Single-crystal X-ray crystallography and density functional theory(DFT)calculations show that compound 3 features a pronounced Sn=Sn double bond and one lone pair of electrons at the two-coordinate Sn *** strikingly,3 undergoes an interconversion with distannyne(4)upon the addition and removal of one molar equivalent of N-heterocyclic *** 3 readily reacts with Ph_(2)C=C=O,Ad C≡P and(Al Cp^(*))_(4)to give the structurally interesting stannacycles(5,6)and an aluminyl distannyne(7),demonstrating its unique reactivity derived from the high substituent lability.

关键词： distannavinylidene silylenes stannacycles distannyne carboranes

Conformation of an Amphiphilic Comb-like Copolymer in a Selective Solvent

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Chinese Journal of Polymer Science 2023年第9期41卷 1386-1391,I0006页

作者： Peng Hao Xing-Hong Mai qiao-Yue Chen ming-ming Ding Xinjiang Laboratory of Phase Transitions and Microstructures in Condensed Matter Physics College of Physical Science and TechnologyYili Normal UniversityYining835000China School of Chemical Engineering and Light Industry Guangdong University of TechnologyGuangzhou510006China

We study the conformation of an amphiphilic comb-like copolymer in a selective solvent by using Brownian dynamics *** results demonstrate that,there is an optimal total degree of polymerization to form spherical *** when the total degree of polymerization is less than the optimal total degree of polymerization,a unimolecular spherical micelle can be formed,otherwise,the spherical micelle will be transformed into a cylindrical *** the total degree of polymerization is less than the optimal total degree of polymerization,the radius of gyration and the stretching factor meet an exponential relationship,where the power exponent decreases with the increase of the length of hydrophilic side *** fundamental principles uncovered here afford insights for the optimization of molecular design of amphiphilic comb-like copolymers in various applications.

关键词： Comb-like copolymer Conformation Selective solvent Brownian dynamics

Repairing of rutin to the toxicity of combined F-53B and chromium pollution on the biofilm formed by Pseudomonas aeruginosa

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Journal of Environmental Sciences 2023年第5期127卷 158-168页

作者： Yunhao Zhang Yi Qian ming Zhang Weichuan qiao Department of Environmental Engineering College of Biology and the EnvironmentNanjing Forestry UniversityNanjing 210037China

The wastewater discharge from the process of chrome plating,which contains 6:2 chlorinated polyfluorinated ether sulfonate(F-53B)and chromium(Cr),may be toxic to *** this study we found that the biofilm formed by Pseudomonas aeruginosa PAO1 was inhibited by exposure to a combination of F-53B and Cr(VI).The combined pollution damaged the cell membranes and the structure of the biofilm,and inhibited the production of the Pseudomonas quinolone-based signal,which affected biofilm ***,the secretion of extracellular polymeric substances decreased as a result of this combined *** to F-53B and Cr(VI)individually or in combination could induce the excessive accumulation of intracellular reactive oxygen species(ROS),and the ROS positive rate of the bacteria increased under the treatment with 0.2 mmol/L of Cr(VI)and 250 nmol/L of F-53B,*** addition,the activities of superoxide dismutase(SOD)and catalase(CAT)were enhanced for scavenging ROS in the bacteria that were exposed to Cr(VI)and *** an antioxidant,rutin was used to repair the toxicity of Cr(VI)and F-53B towards the biofilm formed by the *** rutin was added to the bacteria medium,with either Cr(VI)or F-53B as pollutant,or with the combined pollutants,the extracellular protein content of the bacteria recovered to 0.84,0.94,and 0.85 times that of the control,***,the accumulation of ROS and the activities of SOD and CAT decreased,which indicated that the addition of rutin can alleviate the oxidative stress and promote the antioxidant stress system.

关键词： F-53B Chromium(Cr) Rutin Biofilm Toxic effect Repair

Source localization based on symmetrical MUSIC and its statistical performance analysis

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Science China(Information Sciences) 2013年第6期56卷 74-86页

作者： YAN FengGang JIN ming qiao XiaoLin School of Electronics and information Engineering Harbin Institute of Technology Laboratory of Information Engineering Harbin Institute of Technology(Weihai)

In this paper,a new method for fast direction-of-arrival(DOA) estimation with no dependance on array configurations is proposed,which is referred to as the symmetrical multiple signal classification(SMUSIC).Unlike the standard MUSIC,the S-MUSIC spatial spectrum is constructed by the intersection of the noise subspace and the conjugate noise subspace,and it hence generates spectral peaks at the true DOAs and the symmetrical virtual DOAs *** a characteristic allows fast DOA estimation by spectral search over only half of the total angular ***,the new approach has a much lower computational complexity than the standard *** statistical performance of S-MUSIC is studied and a close-form expression for the MSEs(mean square errors) of DOA estimation by the proposed estimator is *** simulations are conducted to demonstrate the effectiveness of the new algorithm and to verify the theoretical analysis,and it is indicated that S-MUSIC makes a trade-off between MSEs and lower computational complexity as well as an improved resolution for closely-spaced sources as compared to the standard MUSIC.

关键词： symmetrical multiple signal classification(S-MUSIC) direction-of-arrival(DOA) estimation alternative projection method(APM) singular value decomposition(SVD) statistical performance analysis

Locally distinguishing genuinely nonlocal sets with entanglement resource

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Communications in Theoretical Physics 2024年第12期76卷 44-51页

作者： qiao qiao Su-Juan Zhang Chen-ming Bai Lu Liu Department of Mathematics and Physics Shijiazhuang Tiedao University

A set of orthogonal product states is deemed genuinely nonlocal if they remain locally indistinguishable under any *** this paper,we first construct a genuinely nonlocal product basis BⅠ（5,3） in C5■ C5■ C5using a set of nonlocal product states in C3■ ***,we obtain a genuinely nonlocal product basis BⅡ（5,3） by replacing certain states in BⅠ（5,3） with some superposition *** achieve perfect discrimination of the constructed genuinely nonlocal product basis,separately employing two EPR states and one GHZ *** protocol is more efficient than quantum teleportation.

关键词： entanglement-assisted discrimination genuinely nonlocal local discrimination

Molecular recognition and biological application of modified β-cyclodextrins

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Science China Chemistry 2019年第5期62卷 549-560页

作者： Ying-ming Zhang qiao-Yan Xu Yu Liu College of Chemistry State Key Laboratory of Elemento-Organic ChemistryNankai University Collaborative Innovation Center of Chemical Science and Engineering (Tianjin)

The molecular recognition based on cyclodextrins(CDs) has become a focus of interest in modern supramolecular *** are known to encapsulate various ions and organic/inorganic molecules in their hydrophobic cavities and form stable inclusion complexes through cooperative noncovalent interactions. During the past few decades, a large variety of modified CDs have been elaborately designed and synthesized, which significantly promotes our molecular-level understanding of the structure–function relationship in many supramolecular systems. Through the accurate analysis on the molecular binding behaviors, one can create a library of CD-based nanoassemblies with controlled physicochemical properties. In this review, we will focus on the stability constant-directed molecular recognition and the biological activities of β-CDs toward some representative bioactive substrates, including metal ions, steroids, porphyrins, amino acids and oligopeptides, as well as drug molecules, with the final goal of promoting their practical applications in the biomedical field.

关键词： Host-guest chemistry molecular recognition cyclodextrin biological function

Computationally efficient direction finding using polynomial rooting with reduced-order and real-valued computations

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Journal of Systems Engineering and Electronics 2016年第4期27卷 739-745页

作者： Fenggang Yan Yi Shen ming Jin Xiaolin qiao School of Information and Electrical Engineering Harbin Institute of Technology School of Astronautics Harbin Institute of Technology at Weihai

The root multiple signal classification（root-MUSIC） algorithm is one of the most important techniques for direction of arrival（DOA） estimation. Using a uniform linear array（ULA） composed of M sensors, this method usually estimates L signal DOAs by finding roots that lie closest to the unit circle of a（2M-1）-order polynomial, where L 〈 M. A novel efficient root-MUSIC-based method for direction estimation is presented, in which the order of polynomial is efficiently reduced to 2L. Compared with the unitary root-MUSIC（U-root-MUSIC） approach which involves real-valued computations only in the subspace decomposition stage, both tasks of subspace decomposition and polynomial rooting are implemented with real-valued computations in the new technique,which hence shows a significant efficiency advantage over most state-of-the-art techniques. Numerical simulations are conducted to verify the correctness and efficiency of the new estimator.

关键词： direction-of-arrival(DOA) estimation root multiple signal classification(root-MUSIC) real-valued computations reduced-order

What is the mass of loess in the Loess Plateau of China?

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Science Bulletin 2019年第8期64卷 534-539页

作者： Yuanjun Zhu Xiaoxu Jia Jiangbo qiao ming'an Shao State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Northwest A&F University Institute of Soil and Water Conservation Chinese Academy of Sciences & Ministry of Water Resources College of Resources and Environment University of Chinese Academy of Sciences Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences

The Loess Plateau of China(LP) has the largest and thickest loess deposits in the world. Quantifying the amount of loess in the LP is crucial for investigating the accumulation and erosion of loess, and determining the regional soil and water resource capacity. We used loess thickness data, a pedotransfer function for bulk density(BD), and the clay content data observed in 242 sites across the LP to derive the BD of loess and then estimate the loess mass and its distribution across the LP. The results indicated that the average BD of loess between the surface and bedrock is 1.58 g cm^(-3), varying from 1.18 to 1.87 g cm^(-3).The total loess mass is approximately 5.45 ? 10^(13) t, and the average loess mass over an area of 1 m^2 is 169 t, ranging from 1.36 to 585 t. The greatest mass of loess is in the south-central of the LP while the lowest mass of loess is in the northwest and river valley areas. Our estimate of loess mass provides key data for calculating water, carbon, and nutrient storages in the LP, which improves our understanding of soil-water processes and ecohydrological systems in this landscape.

关键词： The Loess Plateau Loess mass Pedotransfer function Soil erosion Bulk density

Functionally Oriented Tumor Microenvironment Responsive Polymeric Nanoassembly:Engineering and Applications

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Chinese Journal of Polymer Science 2018年第3期36卷 273-287页

作者： Wen-ming Zhang Jian Zhang Zhu qiao Jun Yin Department of Polymer Science and Engineering School of Chemistry and Chemical EngineeringHefei University of Technology and Anhui Province Key Laboratory of Advanced Catalytic Materials and Reaction EngineeringHefei 230009China

The excellent drug encapsulation,prolonged in vivo circulation time,enhanced pharmacokinetics,and reduced adverse effects make the polymeric assemblies ideal carriers in nanomedicine,and become an emerging research field with rapid *** vivo,the polymer nanoassemblies will experience five steps,including circulation in the blood,accumulation in the tumoral site,penetration into the deep tumor tissue to reach cancer cells,internalization into cancer cells,and intracellular drug ***,although tremendous efforts have been made to the material design,currently available carriers still have difficulties in fulfilling all of the ***,the long-standing dilemma of the synchronized stability and permeability of vesicles is still a big challenge,which confused researchers for a long *** feature article tbcuses on the recent progress of single-or multi-stimuli triggered theranostic platforms,and the extracellularly reengineered shell-sheddable polymeric nanocarriers are systematically *** perspectives for future developments in the nanocarriers functioned with artificial helical polymers(the potential cell-penetrating peptides mimics)are also *** speculate that this feature article can fit the interesting of diverse readers and a guideline for the design of next generation of drug nanocarriers.

关键词： Block copolymers Tumor microenvironment responsive Self-assembly Theranostic Nanomedicine