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Maize gets an iron boost:Biofortification breakthrough holds promise to combat iron deficiency

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Journal of Integrative Plant Biology 2024年第4期66卷 635-637页

作者： Sunil Kumar Sahu State key laboratory of Agricultural genomics Key Laboratory of GenomicsMinistry of AgricultureBGI ResearchShenzhen 518083China BGI Research Wuhan 430074China

Micronutrient deficiencies affect more than two billion people worldwide,resulting in poor health,developmental issues,and even death.Iron deficiency is one of the most prevalent micronutrient deficiencies worldwide a... 详细信息

关键词： population breakthrough holds

Ionic liquid-assisted preparation of hydroxyapatite and its catalytic performance for decarboxylation of itaconic acid

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Chinese Journal of chemical Engineering 2024年第3期67卷 9-15页

作者： Shutong Pang Hualiang An Xinqiang Zhao Yanji Wang Hebei Provincial key laboratory of Green chemical Technology and Efficient Energy Saving Tianjin Key Laboratory of Chemical Process SafetySchool of Chemical Engineering and TechnologyHebei University of TechnologyTianjin 300130China

The synthesis of methacrylic acid from biomass-derived itaconic acid is a green route,for it can get rid of the dependence on fossil resource.In order to solve the problems on this route such as use of a preciousmetal catalyst and a corrosive homogeneous alkali,we prepared a series of hydroxyapatite catalysts by an ionic liquid-assisted hydrothermal method and evaluated their catalytic performance.The results showed that the ionic liquid[Bmim]BF_(4) can affect the crystal growth of hydroxyapatite,provide fluoride ion for fluorination of hydroxyapatite,and adjust the surface acidity and basicity,morphology,textural properties,crystallinity,and composition of hydroxyapatite.The[Bmim]BF4 dosage and hydrothermal temperature can affect the fluoride ion concentration in the hydrothermal system,thus changing the degree of fluoridation of hydroxyapatite.High fluoride-ion concentration can lead to the formation of CaF_(2) and thus significantly decrease the catalytic performance of hydroxyapatite.The hydrothermal time mainly affects the growth of hydroxyapatite crystals on the c axis,leading to different catalytic performance.The suitable conditions for the preparation of this fluoridized hydroxyapatite are as follows:a mass ratio of[Bmim]BF4 to calcium salt=0.2:1,a hydrothermal time of 12 h,and a hydrothermal temperature of 130℃.A maximal methacrylic acid yield of 54.7%was obtained using the fluoridized hydroxyapatite under relatively mild reaction conditions(250℃ and 2 MPa of N_(2))in the absence of a precious-metal catalyst and a corrosive homogeneous alkali.

关键词： Ionic liquid Hydroxyapatite Itaconic acid Methacrylic Decarboxylation reaction

Cobalt-Catalyzed Switchable[4+1]and[4+1+1]Spirocyclization of Aromatic Amides with 2-Diazo-1H-indene-1,3(2H)-dione:Access to Spiro Indene-2,1'-isoindolinones and Spiro Isochroman-3,1'-isoindolinones

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Chinese Journal of Chemistry 2024年第4期42卷 363-369页

作者： Bin Li Mengmeng Xie Jingyu Li Nana Shen Xinying Zhang Xuesen Fan State key laboratory of Antiviral Drugs Pingyuan LaboratoryKey Laboratory of Green Chemical Media and ReactionsKey Laboratory for Yellow River and Huai River Water Environmental Pollution ControlMinistry of EducationSchool of EnvironmentSchool of Chemistry and Chemical EngineeringHenan Normal UniversityXinxiangHenan453007 China

Herein,we report a condition-controlled divergent synthesis of spiro indene-2,1'-isoindolinones and spiro isochroman-3,1'-isoindolinones through cobalt-catalyzed formal[4+1]and[4+1+1]spirocyclization of aromatic amides with 2-diazo-1H-indene-1,3(2H)-dione.When the reaction is carried out under air in ethyl acetate,spiro indene-2,1'-isoindolinones are formed through Co(II)-catalyzed C—H/N—H[4+1]spirocyclization.When the reaction is run under O2 in CH3CN,on the other hand,spiro isochroman-3,1'-isoindolinones are generated through Baeyer-Villiger oxidation of the in situ formed spiro indene-2,1'-isoindolinones with O2 as a cheaper and environmental-friendly oxygen source.In general,these protocols have advantages such as using non-precious and earth-abundant metal catalyst,no extra additive,high efficiency and regioselectivity.A gram-scale synthesis and the removal of the directing group further highlight its utility.

关键词： Spiro indene-2,1'-isoindolinones Spiro isochroman-3,1'-isoindolinones 3d Transition metals Cobalt-catalyzed C-H Activation Switchable[4+1]and[4+1+1]spirocyclization Aromatic amides 2-Diazo-1H-indene-1,3(2H)-dione

Vanadium(V) Complexes Containing Unsymmetrical N-Heterocyclic Carbene Ligands: Highly Efficient Synthesis and Catalytic Behavior towards Ethylene/Propylene Copolymerization

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Chinese Journal of Polymer Science 2024年第1期42卷 32-41,I0006页

作者： Yi-Cong Wang Hui Zhat Pei-Yi Cheng Shu Zhang Xiang-Wei Liu Yi-Xian Wu State key laboratory of chemical Resource Engineering Beijing University of Chemical TechnologyBejing 100029China

The highly efficient method has been developed for the synthesis of NHC·VOCl_(3) containing symmetrical or unsymmetrical Nheterocyclic carbene(NHC) ligands by the transmetallation reaction of NHC·AgCl with VOCl_(3).The total isolated yield of VOCl_(3)[1,3-(2,4,6-Me_(3)C_(6)H_(2))_(2)(NCH=)_(2)C:](V4') reached 86% by transmetallation reaction,which is much higher than that(48%) by direct coordination method.This methodology has also been used to synthesize the novel vanadium complexes containing unsymmetrical NHC ligands of VOCl_(3)[PhCH_(2)NCH=CHNR)C:](V5',R=2,4,6-Me_(3)C_(6)H_(2);V6',R=2,4-Me_(2)-6-Ph-C_(6)H_(2);V7',R=2,6-^(i)Pr_(2)-C_(6)H_(3)) with high yield,which could not be obtained by direct coordination method.The catalytic activity and copolymerization ability would be improved by introducing unsymmetrical NHC ligands due to their less steric bulky effect.The vanadium complex V5' containing unsymmetrical NHC ligand exhibits higher catalytic activity(3.7×10^(5)g_(copolymer)·mol^(-1) of V·h^(-1)) than that of V4' containing symmetrical NHC ligand.Moreover,the higher propylene incorporation ratio(45.6 mol%) in the copolymers of ethylene with propylene could be obtained by using V5' than that(39.9%) by using V4'.The results would provide a highly efficient strategy for the synthesis of early transition metal complexes containing versitile NHC ligands,affording the catalyst with both high catalytic activity and copolymerization ability for the synthesis of high performance polyolefin elastomers.

关键词： Vanadium complex N-heterocyclic carbene ligand Transmetallation reaction Copolymerization of ethylene with propylene

Microfluidic-oriented synthesis of enriched iridium nanodots/carbon architecture for robust electrocatalytic nitrogen fixation

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Green Energy & Environment 2024年第3期9卷 544-555页

作者： Hengyuan Liu Xingjiang Wu Yuhao Geng Xin Li Jianhong Xu The State key laboratory of chemical Engineering Department of Chemical EngineeringTsinghua UniversityBeijing100084China

Electrocatalytic nitrogen reduction reaction(NRR)is considered as a promising candidate to achieve ammonia synthesis because of clean electric energy,moderate reaction condition,safe operating process and harmless by-products.However,the chemical inertness of nitrogen and poor activated capacity on catalyst surface usually produce low ammonia yield and faradic efficiency.Herein,the microfluidic technology is proposed to efficiently fabricate enriched iridium nanodots/carbon architecture.Owing to in-situ co-precipitation reaction and microfluidic manipulation,the iridium nanodots/carbon nanomaterials possess small average size,uniform dispersion,high conductivity and abundant active sites,producing good proton activation and rapid electrons transmission and moderate adsorption/desorption capacity.As a result,the as-prepared iridium nanodots/carbon nanomaterials realize large ammonia yield of 28.73 μg h^(-1) cm^(-2) and faradic efficiency of 9.14%in KOH solution.Moreover,the high ammonia yield of 11.21 μg h^(-1) cm^(-2) and faradic efficiency of 24.30%are also achieved in H_(2)SO_(4) solution.The microfluidic method provides a reference for large-scale fabrication of nano-sized catalyst materials,which may accelerate the progress of electrocatalytic NRR in industrialization field.

关键词： Iridium nanodots Carbon Microfluidic technology Efficient synthesis Electrocatalytic nitrogen fixation

Process intensification for the synthesis and purification of battery-grade Li_(2)CO_(3)with microfluidics

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Particuology 2024年第7期90卷 106-117页

作者： Haodu Li Jie Zhang Lin Dai Le Du Jiqin Zhu The State key laboratory of chemical Resource Engineering College of Chemical EngineeringBeijing University of Chemical TechnologyBeijing 100029China

Battery-grade lithium carbonate(Li_(2)CO_(3))with a purity of higher than 99.5 wt%is of great importance as a high value-added lithium salt.However,influences of different reaction systems and process control on product purity remain unclear.Herein,a membrane dispersion microreactor was used to enhance the mass transfer of preparation and purification processes in homogeneous and heterogeneous system.Synthetic systems of Na_(2)CO_(3)–LiCl,NH_(4)HCO_(3)–LiCl,and NH_(3)·H_(2)O−CO_(2)−LiCl,CO_(2)purification based on carbonation and decomposition were adopted.The Li_(2)CO_(3)purity was increased by the improvement of mixing performance.The carbonation time was reduced by 62.5%and 58.3%for the NH_(3)·H_(2)O−CO_(2)and CO_(2)purification systems,respectively.In the two ammonia-based systems,Li_(2)CO_(3)particles with a purity of 99.7–99.8 wt%were one-step prepared with a size of 3–5μm,which also met the requirement of the battery-grade standard.The purity was further increased to 99.9 wt%by CO_(2)purification and LiHCO_(3)decomposition.The investigation could provide a feasible alternative for the controllable preparation of battery-grade Li_(2)CO_(3)in one or multiple steps.

关键词： Microfluidics Battery grade Li_(2)CO_(3) Process intensification High purity

Energy-saving design and optimization of pressure-swing-assisted ternary heterogenous azeotropic distillations

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Chinese Journal of chemical Engineering 2024年第4期68卷 1-7页

作者： Lianjie Wu Kun Lu Qirui Li Lianghua Xu Yiqing Luo Xigang Yuan Tianjin key laboratory of Organic Solar Cells and Photochemical Conversion College of Chemical and Chemical EngineeringTianjin University of TechnologyTianjin 300384China State key laboratory of chemical Engineering Tianjin UniversityTianjin 300072China

A huge amount of energy is always consumed to separate the ternary azeotropic mixtures by distillations.The heterogeneous azeotropic distillation and the pressure-swing distillation are two kinds of effective technologies to separate heterogeneous azeotropes without entrainer addition.To give better play to the synergistic energy-saving effect of these two processes,a novel pressure-swing-assisted ternary heterogeneous azeotropic distillation(THAD)process is proposed firstly.In this process,the ternary heterogeneous azeotrope is decanted into two liquid phases before being refluxed into the azeotropic distillation column to avoid the aqueous phase remixing,and three columns'pressures are modified to decrease the flowrates of the recycle streams.Then the dividing wall column and heat integration technologies are introduced to further reduce its energy consumption,and the pressureswing-assisted ternary heterogeneous azeotropic dividing-wall column and its heat integration structure are achieved.A genetic algorithm procedure is used to optimize the proposed processes.The design results show that the proposed processes have higher energy efficiencies and lower CO_(2)emissions than the published THAD process.

关键词： Distillation Separation Process control Process systems

π-conjugated chromophore functionalized high-nuclearity titanium-oxo clusters containing structural unit of anatase for photocatalytic selective oxidation of sulfides

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Rare Metals 2024年第4期43卷 1736-1746页

作者： Ling-Rong Liao Dong-Chun Zheng Pin-Xi Ou Qi-Xin Zhao Wei-Min Xuan Qi Zheng State key laboratory for Modification of chemical Fibers and Polymer Materials & College of Materials Science and Engineering Donghua University State key laboratory for Modification of chemical Fibers and Polymer Materials and College of Chemistry and chemical Engineering Donghua University

N-doping has significant influence in manipulating the properties of TiO2,and this has stimulated the development of N-donor-functionalized titanium-oxo clusters（TOCs） as molecular models to study the structure-property relationship.However,the structural type and photoresponsive application are still limited for such TOCs,especially regarding the high-nuclearity TOCs that contain structure unit of TiO2for photocatalysis.Herein,we showed the synthesis of a series of high-nuclearity TOCs 1-3 compounds using π-conjugated 1,10-phenanthroline（phen） as chromophore and N-donor functional ligand.Compound 1 features cocrystal structure composed of one [Ti26]2+and half [Ti22]2+,which renders it as the first cocrystallized TOC containing two positively charged species and phen-functionalized TOC showing the highest nuclearity up to 37 Ti centers.By adjusting the synthetic conditions,the individual {Ti22} and {Ti26} clusters can also be isolated as Compounds 2 and 3,respectively.The core structure of {Ti22} is mainly constructed from four lacunary {Ti4} derived from pentagonal {Ti（Ti）5} unit,while {Ti26} is built from four complete {Ti（Ti）5} unit.Notably,a {Ti8O14} structure unit of anatase TiO2can be identified in {Ti26}.Based on the unique structural features and proper photophysical and photochemical properties of Compounds 1-3,they are applied for photocatalytic sulfoxidation.Owing to the presence of anatase structure unit in {Ti26} and the synergistic effect from {Ti22} and {Ti26},the catalytic performance presents in the order of Compound 1> Compound 3> Compound 2.This work provides excellent models to understand the structureproperty relationship from the perspective of cocrystallization and Ti-O binding model and will further promote the application of TOCs as functional catalysts for organic transformation.

关键词： Titanium-oxo cluster Molecular model of anatase TiO 2 High nuclearity π-conjugated chromophore Photocatalytic sulfoxidation

Improving error-correcting capability in DNA digital storage via soft-decision decoding

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National Science Review 2024年第2期11卷 135-144页

作者：丁璐璐伍世刚候志浩李阿伦许亚苹冯虎潘玮华阮珏 Shenzhen Branch Guangdong Laboratory of Lingnan Modern AgricultureGenome Analysis Laboratory of the Ministry of Agriculture and Rural AffairsAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural Sciences Guangdong Provincial key laboratory of Plant Molecular Breeding State Key Laboratory for Conservation and Utilization of Subtropical Agro-BioresourcesSouth China Agricultural University

Error-correcting codes(ECCs) employed in the state-of-the-art DNA digital storage(DDS) systems suffer from a trade-off between error-correcting capability and the proportion of redundancy. To address this issue, in this study, we introduce soft-decision decoding approach into DDS by proposing a DNA-specific error prediction model and a series of novel strategies. We demonstrate the effectiveness of our approach through a proof-of-concept DDS system based on Reed-Solomon(RS) code, named as Derrick. Derrick shows significant improvement in error-correcting capability without involving additional redundancy in both in vitro and in silico experiments, using various sequencing technologies such as Illumina, Pac Bio and Oxford Nanopore Technology(ONT). Notably, in vitro experiments using ONT sequencing at a depth of 7× reveal that Derrick, compared with the traditional hard-decision decoding strategy, doubles the error-correcting capability of RS code, decreases the proportion of matrices with decoding-failure by 229-fold, and amplifies the potential maximum storage volume by impressive 32 388-fold. Also, Derrick surpasses ‘state-of-the-art' DDS systems by comprehensively considering the information density and the minimum sequencing depth required for complete information recovery. Crucially, the soft-decision decoding strategy and key steps of Derrick are generalizable to other ECCs' decoding algorithms.

关键词： DNA digital storage (DDS) error-correcting code (ECC) soft-decision decoding error-correcting capability storage volume