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Keto-form directed hierarchical chiral self-assembly of Schiff base derivatives with amplified circularly polarized luminescence

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Chinese Chemical Letters 2024年第1期35卷 366-370页

作者： Yimeng Sun Yuqian Jiang Jian Jiang Tiesheng Li minghua liu Green Catalysis Center and College of ChemistryZhengzhou UniversityZhengzhou 450001China Key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing 100190China National Laboratory for Molecular Science(BNLMS) CAS Laboratory of ColloidInterface and Chemical ThermodynamicsInstitute of ChemistryChinese Academy of ScienceBeijing 100190China University of Chinese Academy of Sciences Beijing 100190China

While enol-keto tautomerism has attracted great interest in Schiff bases and related compounds in solution and crystal states,the self-assembly of energy-unfavored keto form were scarcely investigated.Here,we report a keto-form directed self-assembly of a naphthalene-attached enantiomeric N-salicylideneanil analog L/DGG-Nap accompanied with a significantly amplified circularly polarized luminescence(CPL).It was found that LGG-Nap exists as a mixture of enol and keto form in monomer at a diluted toluene solution.The increment of the concentrations leads to the formation of predominated keto form,which subsequently triggers the self-assembly.Cryo-transmission electron microscopy(Cryo-TEM)revealed that a hierarchical assembly process happened upon increasing the concentration of LGG-Nap in toluene.Individual nanofibers formed at 1×10-4 mol/L and transferred into helical nanofiber bundles in 5×10-3 mol/L.Interestingly,while these is nearly no circular dichroism(CD)or CPL in the monomeric solution,the assembly showed strong CD and CPL.Remarkably,the dissymmetry factor(glum)was significantly amplified from zero in solution through the 0.005 in individual nanofiber to 0.1 in nanofiber bundles.This work demonstrates that the enol-keto tautomerism can be broken and trigger the self-assembly upon increasing the concentration,which can subsequently direct the chiral self-assembly and significantly amplify the dissymmetry factor of assembled CPL materials.

关键词： Enol-keto tautomerism Chiral self-assembly Schiff base Circularly polarized luminescence Nanofiber bundle

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Data cleaning method for the process of acid production with flue gas based on improved random forest

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中国化学工程学报:英文版 2023年第7期59卷 72-84页

作者： Xiaoli Li minghua liu Kang Wang Zhiqiang liu Guihai Li Faculty of Information Technology Beijing University of TechnologyBeijing 100124China Beijing Key Laboratory of Computational Intelligence and Intelligent System Engineering Research Center of Digital CommunityMinistry of EducationBeijing 100124China Guixi Smelter Jiangxi Copper Co.LtdGuixi 335400China Beijing RTlink Technology Co. LtdBeijing 100102China

Acid production with flue gas is a complex nonlinear process with multiple variables and strong coupling.The operation data is an important basis for state monitoring,optimal control,and fault diagnosis.However,the operating environment of acid production with flue gas is complex and there is much equipment.The data obtained by the detection equipment is seriously polluted and prone to abnormal phenomena such as data loss and outliers.Therefore,to solve the problem of abnormal data in the process of acid production with flue gas,a data cleaning method based on improved random forest is proposed.Firstly,an outlier data recognition model based on isolation forest is designed to identify and eliminate the outliers in the dataset.Secondly,an improved random forest regression model is established.Genetic algorithm is used to optimize the hyperparameters of the random forest regression model.Then the optimal parameter combination is found in the search space and the trend of data is predicted.Finally,the improved random forest data cleaning method is used to compensate for the missing data after eliminating abnormal data and the data cleaning is realized.Results show that the proposed method can accurately eliminate and compensate for the abnormal data in the process of acid production with flue gas.The method improves the accuracy of compensation for missing data.With the data after cleaning,a more accurate model can be established,which is significant to the subsequent temperature control.The conversion rate of SO_(2) can be further improved,thereby improving the yield of sulfuric acid and economic benefits.

关键词： Acid production Data cleaning Isolation forest Random forest Data compensation

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Stride the chirality transfer across length scales by merging the boundaries between solution and interfacial self-assembly

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Chinese Journal of Structural Chemistry 2023年第4期42卷 1-3页

作者： Guanghui Ouyang minghua liu CAS Key Laboratory of Colloid Interface and ThermodynamicsInstitute of ChemistryChinese Academy of SciencesNo.2 North First StreetZhongguancunBeijing100190China

The chiral self-assembly of functional molecules,polymers and clus-ters into nanoscale objects with well-defined ordering,asymmetry and in some cases out-of-equilibrium characteristics is an important strategy to fabricate novel materials[1],which might address key challenges at the heart of energy,environmental and biomedical applications.In recent years,subsequent utilization of these nanoscale units as new building blocks to fabricate advanced structures and realize more complex func-tions like those in the biology systems has aroused interests.These at-tempts are originated from the concept of molecular nanotechnology but have gone beyond its boundaries towards the breakthroughs of self-assembled machines,advanced nanoarchitectonics and molecular nanotopology[2,3].

关键词： interfacial breakthrough subsequent

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Chiral porphyrin assemblies

聚集体(英文)

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聚集体(英文) 2023年第1期4卷 27-40页

作者： Li Zhang TianyuWang Jianzhuang Jiang minghua liu Beijing National Laboratory for Molecular Science(BNLMS) CAS Key Laboratory of ColloidInterface and Chemical ThermodynamicsInstitute of ChemistryChinese Academy of SciencesBeijingP.R.China Beijing Key Laboratory for Science and Application of Functional Molecular and Crystalline Materials Department of ChemistryUniversity of Science and Technology BeijingBeijingP.R.China

Porphyrins are among the most important macrocycles because they perform many essential functions in living systems and serve as building blocks in many functional materials.Incorporating the chirality into porphyrins can aid biomimetic research and the exploration of new functional materials.In this review,recent developments in chiral porphyrin assemblies are highlighted.The review is mainly divided into two sections:the different strategies for constructing chiral porphyrin assemblies and the applications.The formation of chiral porphyrin assemblies can be from porphyrin molecules substituted with chiral groups;achiral porphyrins induced by chiral additives and spontaneous deracemizations of achiral porphyrins during the assemblies.We also provide an overview of the applications of chiral porphyrin assemblies in chiral sensing,asymmetry catalysis,circularly polarized luminescence,and so on.The further challenge in the field is discussed.

关键词： chiral circularly polarized luminescence helical porphyrins self-assembly

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Spiral fractal patterns via hierarchical assembly

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Nano Research 2022年第2期15卷 1079-1086页

作者： Li Zhang Ming Deng Yu Duan Xin Wen Yuqian Jiang Hejin Jiang Yuqiang Ma minghua liu Beijing National Laboratory for Molecular Science(BNLMS) CAS Key Laboratory of ColloidInterface and Chemical Thermodynamics Institute of ChemistryChinese Academy of SciencesBeijing 100190China National Laboratory of Solid State Microstructures and Department of Physics Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China National Center for Nanoscience and Technology Beijing 100190China

Chirality is ubiquitous in nature and manifested at various scale from subatom to galaxy.Fractal geometry is also very popular and active in the world.However,there are few reports on the concept of combining fractal patterns and chiral structures in self-assembled systems.It was found that tree-shaped fractal patterns could be self-assembled from the N-[(9H-fluoren-9-ylmethoxy)carbonyl]protected glutamic acid(Fmoc-Glu)and zinc-porphyrin(ZnTPyP).The fractal pattern was composed of nanorod aggregate arranged in a spiral fractal way,in which the nanorods were stacked one-by-one in a single direction.The patterns started with the formation of initial nucleon and growing,during which the diffusion limited aggregation(DLA)mechanism led to the fractal patterns.Interestingly,the spiral packing and their branches were closely related to the absolute configuration of Fmoc-Glu that anticlockwise and clockwise arrangement for L-Fmoc-Glu/ZnTPyP and D-Fmoc-Glu/ZnTPyP,respectively.Our work provides a new finding on the spiral fractal pattern via hierarchical self-assembly.

关键词： self-assembly chiral spiral fractal porphyrin

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Late Holocene brGDGTs-based quantitative paleotemperature reconstruction from lacustrine sediments on the western Tibetan Plateau

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Frontiers of Earth Science 2023年第4期17卷 997-1011页

作者： Xiumei LI Sutao liu Juzhi HOU Zhe SUN Mingda WANG Xiaohuan HOU minghua liu Junhui YAN Lifang ZHANG Henan Key Laboratory for Synergistic Prevention of Water and Soil Environmental Pollution School of Geographic SciencesXinyang Normal UniversityXinyang 464000China Institute of Tibetan Plateau Research Chinese Academy of SciencesBeijing 100101China Institute of Geography and Resources Science Sichuan Normal UniversityChengdu 610066China School of Geography Liaoning Normal UniversityDalian 116029China

We present a quantitative mean annual air temperature(MAAT)record spanning the past 4700 years based on the analysis of branched glycerol dialkyl glycerol tetraethers(brGDGTs)from a sediment core from Xiada Co,an alpine lake on the western Tibetan Plateau(TP).The record indicates a relatively stable and warm MAAT until 2200 cal yr BP;subsequently,the MAAT decreased by~4.4℃ at~2100 cal yr BP and maintained a cooling trend until the present day,with centennial-scale oscillations centered at~800 cal yr BP,~600 cal yr BP,and~190-170 cal yr BP.MAAT decreased abruptly at~500-300 cal yr BP and reached its minimum for the past 4700 years.We assessed the representativeness of our record by comparing it with 15 published paleotemperature records from the TP spanning the past~5000 years.The results show divergent temperature variations,including a gradual cooling trend,a warming trend,and no clear trend.We suggest that these discrepancies could be caused by factors such as the seasonality of the temperature proxies,the length of the freezing season of the lakes,the choice of proxy-temperature calibrations,and chronological errors.Our results highlight the need for more high-quality paleotemperature reconstructions with unambiguous climatic significance,clear seasonality,site-specific calibration,and robust dating,to better understand the processes,trends,and mechanisms of Holocene temperature changes on the TP.

关键词： Tibetan Plateau lake sediments branched GDGTs paleotemperature

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Topological-skeleton controlled chirality expression of supramolecular hyperbranched and linear polymers

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Fundamental Research 2022年第3期2卷 422-428页

作者： Xin Song Xuefeng Zhu Hao Yao Weili Shang Cong Du Wensheng Lu minghua liu Wei Tian Shaanxi Key Laboratory of Macromolecular Science and Technology MOE Key Laboratory of Material Physics and Chemistry under Extraordinary ConditionsSchool of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Beijing National Laboratory for Molecular Sciences(BNLMS) Key Laboratory of ColloidInterface and Chemical ThermodynamicsInstitute of ChemistryChinese Academy of Sciences(CAS)ZhongGuanCun North First Street 2Beijing 100190China University of Chinese Academy of Sciences Beijing 100190China School of Civil Engineering Central South UniversityChangsha 410075China

The topology of polymers plays an essential role in their chemical,physical and biological properties.However,their effects on chirality-related functions remain unclear.Here,we reported the topology-controlled chirality expression in the chiral supramolecular system for the first time.Two topological supramolecular polymers,hy-perbranched(HP)and linear(LP)supramolecular polymers produced by the host-guest interactions of branched and linear monomers,respectively,exhibited completely different chirality expressions despite the same molecu-lar chirality of their monomers.Significantly,due to the branch points and strong steric hindrance existing in HP,cis-HP showed an enhanced and sign-inverted Cotton effect in the n-π^(∗)bands compared with cis-LP,as a result that the distinctive chirality induction and transfer were controlled by the topological skeletons.This topology-controlled chirality induction and transfer in the photoswitchable supramolecular polymers not only enables us to elucidate the in-depth effects of topology on the chiral expression in biopolymers but also inspires the design of chiroptical and bioinspired materials.

关键词： Supramolecular chirality Topological skeleton Supramolecular polymer Host-guest interaction Photoisomerization

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Highly efficient and selective removal of low-concentration antibiotics from aqueous solution by regenerable Mg（OH）2

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Journal of Environmental Sciences 2020年第1期32卷 228-237页

作者： Yongjing Wang Jingjing Lin Yonghao Wang Zemeng liu Jinlu Lian minghua liu Fujian Provincial Engineering Research Center for High-value Utilization Technology of Plant Resources College of Environment and ResourcesFuzhou University

The prevalent presence of fluoroquinolone antibiotics in aquatic environments has attracted considerable attention because of their harmful effects on humans and the ecological environment.Magnesium hydroxide nanocrystals were found to act as a simple and effective adsorbent to remove low-concentration ciprofloxacin(CIP)in aqueous solution.The as-prepared Mg(OH)2 nanocrystals exhibited excellent CIP adsorption performance and high selectivity toward CIP molecules compared with other antibiotics or aromatics,e.g.,norfloxacin(NOR)and eosin B(EB).The adsorbent showed pH-dependent adsorption,indicating that the adsorption process is probably dominated by an electrostatic interaction mechanism.In addition,structural analysis of the adsorbent indicated that coordination and hydrogen bonding between CIP and Mg(OH)2 nanocrystal might also be involved in the adsorption process.Moreover,the adsorbent could be easily recovered by pyrolysis and hydration without significant reduction of adsorption capacity.The superior adsorption behavior of Mg(OH)2 nanocrystal indicates that it may serve as a potential adsorbent material candidate for the selective removal of CIP from aquatic environments.

关键词： Magnesium hydroxide nanocrystals Antibiotics Adsorption Selectivity adsorption Regenerable

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Bio-remediation of acephate–Pb(Ⅱ) compound contaminants by Bacillus subtilis FZUL-33

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Journal of Environmental Sciences 2016年第7期28卷 94-99页

作者： Wenting Lin Zhen Huang Xuezhen Li minghua liu Yangjian Cheng The College of Environment and Resources Fuzhou University

Removal of Pb^（2＋）and biodegradation of organophosphorus have been both widely investigated respectively. However, bio-remediation of both Pb^（2＋）and organophosphorus still remains largely unexplored. Bacillus subtilis FZUL-33, which was isolated from the sediment of a lake, possesses the capability for both biomineralization of Pb^（2＋）and biodegradation of acephate. In the present study, both Pb^（2＋）and acephate were simultaneously removed via biodegradation and biomineralization in aqueous solutions.Batch experiments were conducted to study the influence of p H, interaction time and Pb^（2＋）concentration on the process of removal of Pb2＋. At the temperature of 25°C, the maximum removal of Pb^（2＋）by B. subtilis FZUL-33 was 381.31 ± 11.46 mg/g under the conditions of p H 5.5, initial Pb^（2＋）concentration of 1300 mg/L, and contact time of 10 min. Batch experiments were conducted to study the influence of acephate on removal of Pb^（2＋）and the influence of Pb2＋on biodegradation of acephate by B. subtilis FZUL-33. In the mixed system of acephate–Pb2＋, the results show that biodegradation of acephate by B. subtilis FZUL-33 released PO43＋, which promotes mineralization of Pb2＋. The process of biodegradation of acephate was affected slightly when the concentration of Pb2＋was below 100 mg/L. Based on the results, it can be inferred that the B. subtilis FZUL-33 plays a significant role in bio-remediation of organophosphorus-heavy metal compound contamination.

关键词： Acephate–Pb2＋ Bacillus subtilis Biodegradation Biomineralization

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Recent Progress of Circularly Polarized Luminescence Materials from Chinese Perspectives

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CCS Chemistry 2023年第12期5卷 2760-2789页

作者： Xuefeng Yang Xiaoqing Gao You-Xuan Zheng Hua Kuang Chuan-Feng Chen minghua liu Pengfei Duan Zhiyong Tang CAS Key Laboratory of Nanosystem and Hierarchical Fabrication National Center for Nanoscience and Technology(NCNST)Beijing 100190 Wenzhou Key Laboratory of Biophysics Wenzhou InstituteUniversity of Chinese Academy of SciencesWenzhouZhejiang 325000 State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023 International Joint Research Laboratory for Biointerface and Biodetection State Key Lab of Food Science and TechnologySchool of Food Science and TechnologyJiangnan UniversityWuxi 214122 Beijing National Laboratory of Molecular Sciences and CAS Key Laboratory of Colloid Interface and ThermodynamicsInstitute of ChemistryChinese Academy of SciencesBeijing 100190

The research on circularly polarized luminescence(CPL)has garnered significant attention in recent years due to its many potential applications.One aspect of this research involves the pursuit of chiral materials that posess both high luminescence efficiency and dissymmetry factors.The investigation of CPL behavior is of paramount importance because the structural information of chiral luminescent systems in the excited state can be uncovered.The objective of this review is to offer a comprehensive overview of the latest advancements in the CPL research field,with a particular focus on the development of chiral emissive materials,including organic,inorganic,and hybrid substances.Furthermore,this review outlines the recent applications of these materials in areas such as displays,photoelectric devices,anticounterfeiting measures,and sensors.Finally,we highlight the primary challenges and potential prospects of CPL materials.Our aspiration is that this endeavor will contribute new perspectives and insights that further advancements in related research fields.

关键词： circularly polarized luminescence circularly polarized electroluminescence circular dichroism optoelectronic materials excited-state chirality chirality

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