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Enzyme-driven Nanorobots Walking Along Predesigned Tracks on the DNA Origami for Cargo Transport and Catalysis

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Chemical Research in Chinese Universities 2024年第2期40卷 333-342页

作者： NIE Cunpeng ma Tianran CHEN Tingting CHU xia State Key Laboratory of Chemo/Bio-Sensing and Chemometrics College of Chemistry and Chemical EngineeringHunan UniversityChangsha410082P.R.China

In molecular engineering,designing and synthesizing molecular machines with capable of performing complex tasks,remains a formidable *** is an excellent candidate for building molecular robots because it is highly ***,we present an artificial nanorobot,in which a DNA cube serves as the inert‘body’,and nucleic acid catalysts based on an enzymatic nicking reaction act as the‘legs’for *** nanorobot can execute a series of actions,such as‘start’,‘turn’,and‘stop’when it walks along a predefined *** performance could be confirmed and monitored by using an atomic force microscope(AFM)and fluorescence *** by biological machines,we artificially designed a series of specialized tasks that combined walking with control of cargo transport and ***-time fluorescence kinetics curves provide monitoring signals for cargo transport and catalytic *** work can enrich the toolbox of DNA machinery and has great potential for engineering molecular nanofactories.

关键词： DNA origami DNA nanorobot Controlled cargo transport DNAzyme catalysis

Pickering emulsion transport in skeletal muscle tissue:A dissipative particle dynamics simulation approach

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Chinese Journal of Chemical Engineering 2024年第4期68卷 65-75页

作者： Xuwei Liu Wei Chen Yufei xia Guanghui ma Reiji Noda Wei Ge State Key Laboratory of Mesoscience and Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China Division of Environmental Engineering Science Graduate School of Science and TechnologyGunma University1-5-1 Tenjin-choKiryuGunma 376-8515Japan State Key Laboratory of Biochemical Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China Innovation Academy for Green manufacture Chinese Academy of SciencesBeijing 100190China

Lymph node targeting is a commonly used strategy for particulate vaccines,particularly for Pickering ***,extensive research on the internal delivery mechanisms of these emulsions,especially the complex intercellular interactions of deformable Pickering emulsions,has been surprisingly *** gap in knowledge holds significant potential for enhancing vaccine *** study aims to address this by summarizing the process of lymph-node-targeting transport and introducing a dissipative particle dynamics simulation method to evaluate the dynamic processes within cell *** transport of Pickering emulsions in skeletal muscle tissue is specifically investigated as a case *** factors impacting the transport process are explored,including local cellular tissue environmental factors and the properties of the Pickering emulsion *** simulation results primarily demonstrate that an increase in radial repulsive interaction between emulsion particles can decrease the transport ***,larger intercellular gaps also diminish the transport efficiency of emulsion droplet particles due to the increased motion complexity within the intricate transport space compared to a single *** study sheds light on the nuanced interplay between engineered and biological systems influencing the transport dynamics of Pickering *** insights hold valuable potential for optimizing transport processes in practical biomedical applications such as drug ***,the desired transport efficiency varies depending on the specific *** instance,while a more rapid transport might be crucial for lymph-node-targeted drug delivery,certain applications requiring a slower release of active components could benefit from the reduced transport efficiency observed with increased particle repulsion or larger intercellular gaps.

关键词： Pickering emulsion Skeletal muscular cells Transport phenomena Dissipative particle dynamics Drug delivery

Physical and numerical investigations of target stratum selection for ground hydraulic fracturing of multiple hard roofs

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International Journal of Mining Science and Technology 2024年第5期34卷 699-712页

作者： Binwei xia Yanmin Zhou Xingguo Zhang Lei Zhou Zikun ma State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing UniversityChongqing 400044China School of Resources and Safety Engineering Chongqing UniversityChongqing 400044China

Ground hydraulic fracturing plays a crucial role in controlling the far-field hard roof,making it imperative to identify the most suitable target stratum for effective *** experiments are conducted based on engineering properties to simulate the gradual collapse of the roof during longwall top coal caving(LTCC).A numerical model is established using the material point method(MPM)and the strain-softening damage constitutive model according to the structure of the physical *** simulations are conducted to analyze the LTCC process under different hard roofs for ground hydraulic *** results show that ground hydraulic fracturing releases the energy and stress of the target stratum,resulting in a substantial lag in the fracturing of the overburden before collapse occurs in the hydraulic fracturing *** hydraulic fracturing of a low hard roof reduces the lag effect of hydraulic fractures,dissipates the energy consumed by the fracture of the hard roof,and reduces the abutment ***,it is advisable to prioritize the selection of the lower hard roof as the target stratum.

关键词： Target stratum selection Ground hydraulic fracturing Hard roof control Fracture network material point method

Insight into the Role and Evidence of Oxygen Vacancies in Porous Single-Crystalline Oxide to Enhance Catalytic Activity and Durability

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Research 2024年第2期2023卷 675-683页

作者： Lingting Ye Jiaming ma Jie Zhang Wen Yin Yuanguang xia Kui Xie Key Laboratory of Optoelectronic materials Chemistry and Physics Fujan Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhouFujian 350002China Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China FuzhouFujian 350108China Advanced Energy Science and Technology Guangdong Laboratory 29 Sanxin North RoadHuizhouGuangdong 116023China Spallation Neutron Source Science Center DongguanGuangdong 523803China

Introducing and stabilizing oxygen vacancies in oxide catalysts is considered to be a promising strategy for improving catalytic activity and ***,we quantitatively create oxygen vacancies in the lattice of porous single-crystallineβ-Ga_(2)O_(3)monoliths by reduction treatments and stabilize them through the long-range ordering of crystal lattice to enhance catalytic activity and *** combination analysis of time-of-flight neutron powder diffraction and extended x-ray absorption fine structure discloses that the preferential generation of oxygen vacancy tends to occur at the site of tetrahedral coordination oxygen ions(O_(Ⅲ)sites),which contributes to the formation of unsaturated Ga-O coordination in the monoclinic *** oxygen vacancies are randomly distributed in lattice even though some of them are present in the form of domain defect in the PSC Ga_(2)O_(3)monoliths after the reduction *** number of oxygen vacancies in the reduced monoliths gives 2.32×10^(13),2.87×10^(13),and 3.45×10^(13)mg^(-1)for the Ga_(2)O_(2.952),Ga_(2)O_(2.895),and Ga_(2)O_(2.880),*** therefore demonstrate the exceptionally high C_(2)H_(4)selectivity of~100%at the C_(2)H_(6)conversion of~37%for nonoxidative dehydrogenation of C_(2)H_(6)to C_(2)H_(4).We further demonstrate the excellent durability even at 620℃for 240 h of continuous operation.

关键词： durability coordination Oxygen

Sensing matrix Optimization for Random Stepped-Frequency Signal Based on Two-Dimensional Ambiguity Function

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Chinese Journal of Electronics 2024年第1期33卷 161-174页

作者： Mingjiu LYU Hao CHEN Jun YANG xia WU Ming ZHOU xiaoyan ma Radar NCO School Air Force Early Warning Academy Department of Early Warning Technology Air Force Early Warning Academy

Compressive sensing technique has been widely applied to achieve range-Doppler reconstruction of high frequency radar by utilizing sparse random stepped-frequency(SRSF) signal, which can suppress the complex electromagnetic interference and greatly reduce the coherent processing interval. An important way to improve the performance of sparse signal reconstruction is to optimize the sensing matrix(SM). However, the existing research on the SM optimization needs to design a measurement matrix with superior performance, which needs a large amount of computation and does not consider the influence of the waveform parameters design. In order to improve the superior reconstruction performance, a novel SM optimization approach for SRSF signal is proposed by using two-dimensional ambiguity function(TDAF) in this paper. Firstly, based on the two-dimensional sparse reconstruction model of the SRSFs, the internal relationship between the waveform parameters and the SM was derived. Secondly, the SM optimization problem was directly transformed into the waveform design of SRSFs. Furthermore, on the basis of analyzing the relationship between the mutual coherence matrix of SM and the TDAF matrix of SRSFs, the purpose of optimizing the SM can be achieved by designing the TDAF of the SRSFs. Based on this analysis, a sparse waveform optimization method with joint constraints of maximum and mean sidelobes of the TDAF by using the genetic algorithm was derived. Compared with the traditional SM optimization method, our method not only avoids generating a new measurement matrix, but also further reduces the complexity of the waveform optimization. Simulation experiments verified the effectiveness of the proposed method.

关键词： Correlation Computational modeling Electromagnetic interference Optimization methods Signal reconstruction High frequency radar Sensors

Transient flameout process of boron-magnesium agglomerates during combustion in oxygen-rich atmospheres

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Particuology 2024年第5期88卷 290-301页

作者： Lian Duan Zhixun xia Yunchao Feng Binbin Chen Likun ma Jianxin Hu College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China School of Mechanical Engineering and Mechanics Xiangtan UniversityXiangtan 411105China

In this study,boron–magnesium agglomerates with varying mass ratios were prepared by drying a micron-sized boron–magnesium mixed suspension,and the combustion process of these agglomerates under different oxygen-rich concentrations were investigated using a laser ignition *** test results showed that when the mass fraction of magnesium powder in boron-magnesium agglomerates exceeded a certain threshold(between 2%and 5%),flame extinction and reignition occurred after a significant reduction in the agglomerate volume during *** process is referred to as the transient flameout process,which is affected by the magnesium content of the agglomerate and the oxygen concentration in the ambient *** increase in the magnesium content or oxygen concentration makes this phenomenon more *** weakening of the flame intensity,a dark film gradually covered the particle surfaces.X-ray diffraction and elemental analyses of the cross-section and outer surface of the condensed combustion product suggested that the dark film is primarily composed of Mg-B-O ternary *** film prevents direct contact between boron and oxygen,thereby inhibiting surface and gas-phase reactions and leading to the occurrence of the transient flameout phenomenon.

关键词： Agglomerated particle Boron–magnesium fuel Boron combustion Transient flameout process Solid fuel ramjet

Non-Fully Conjugated Photovoltaic materials with Y-Series Acceptor Backbone for High-Performance Organic Solar Cells

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Chinese Journal of Chemistry 2024年第11期42卷 1307-1318页

作者： Hairui Bai Qunping Fan Ruijie ma xia Guo Wei ma maojie Zhang State Key Laboratory for Mechanical Behavior of materials Xi’an Jiaotong UniversityXi’anShaanxi710049 China National Engineering Research Center for Colloidal materials School of Chemistry&Chemical EngineeringShandong UniversityJinanShandong250100 China Department of Electronic and Information Engineering Research Institute for Smart Energy(RISE)The Hong Kong Polytechnic UniversityKowloon999077 Hong KongChina

In the last few years,organic solar cells(OSCs)have made significant progress in photovoltaic performance,mainly due to the innovative development of active layer materials,especially Y-series and related derivatives as acceptors which have become the key factor that boosts the power conversion ***,to achieve high-performance OSCs,an emerging molecular design strategy of applying flexible alkyl units as linkers to construct non-fully conjugated acceptors has been developed and addressed great *** review highlights the non-fully conjugated photovoltaic materials with Y-series backbone that enable high-performance *** OSCs have been achieved by some representative non-fully conjugated material *** related molecular design strategies are discussed in ***,a brief summary and future prospect are provided in advancing the non-fully conjugated photovoltaic materials with Y-series backbone towards the brighter future.

关键词： Organic solar cells All-polymer solar cells Non-fully conjugated photovoltaic materials Power conversion efficiency Polymer acceptors Organicel ectronics

Enhancing capacitive deionization performance and cyclic stability of nitrogen-doped activated carbon by the electro-oxidation of anode materials

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Chinese Journal of Chemical Engineering 2024年第5期69卷 23-33页

作者： xiaona Liu Baohua Zhao Yanyun Hu Luyue Huang Jingxiang ma Shuqiao Xu Zhonglin xia.xia.ying ma Shuangchen ma School of Environmental Science and Engineering North China Electric Power UniversityBaoding 071003China Huadian Zhengzhou machinery Design and Research Institute Co. LtdZhengzhou 450002China Huadian Inner Mongolia Energy Co. Ltd.Baotou Power Generation BranchBaotou 014013China

Electrode materials with high desalination capacity and long-term cyclic stability are the focus of capacitive deionization(CDI) community. Understanding the causes of performance decay in traditional carbons is crucial to design a high-performance material. Based on this, here, nitrogen-doped activated carbon(NAC) was prepared by pyrolyzing the blend of activated carbon powder(ACP) and melamine for the positive electrode of asymmetric CDI. By comparing the indicators changes such as conductivity, salt adsorption capacity, pH, and charge efficiency of the symmetrical ACP-ACP device to the asymmetric ACP-NAC device under different CDI cycles, as well as the changes of the electrochemical properties of anode and cathode materials after long-term operation, the reasons for the decline of the stability of the CDI performance were revealed. It was found that the carboxyl functional groups generated by the electro-oxidation of anode carbon materials make the anode zero-charge potential(E_(pzc)) shift positively,which results in the uneven distribution of potential windows of CDI units and affects the adsorption capacity. Furthermore, by understanding the electron density on C atoms surrounding the N atoms, we attribute the increased cyclic stability to the enhanced negativity of the charge of carbon atoms adjacent to quaternary-N and pyridinic-oxide-N.

关键词： Anodic oxidation Capacitive deionization Cyclic stability N-doping

Effects of oxygen vacancy on bond ionicity,lattice energy,and microwave dielectric properties of CeO_(2) ceramics with Yb^(3+) substitution

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Journal of Advanced Ceramics 2024年第2期13卷 247-254页

作者： Mingan Shi Shuyang ma Wangsuo xia Ying Wang Jinzi Yu Haitao Wu School of materials Science and Physics China University of Mining and TechnologyXuzhou 221008China School of Environment and material Engineering Yantai UniversityYantai 264005China

Novel Yb_(x)Ce_(1-x)O_(2-0.5x)(x=0-0.8)ceramics,designed by replacing Ce^(4+)with Yb^(3+)ions were prepared by conventional oxide reaction,and the structural stability of the cubic fluorite structure was assessed using lattice energy and ionic properties of Ce/Yb-O *** oxygen vacancy caused by unequal substitution,which played a decisive role in bond ionicity and lattice energy,was analyzed experimentally by XPS and also theoretically by first *** Yb_(x)Ce_(1-x)O_(2-0.5x) ceramics maintain a stable cubic fluorite structure when x≤0.47,corresponding to the minimum lattice energy of 4142 kJ/mol with the lowest ionicity as ƒ_(i)=87.57%.For microwave dielectric properties,when the Yb_(x)Ce_(1-x)O_(2-0.5x)(x=0-0.4)ceramics are pure phase,the porosity-corrected permittivity is dependent on the bond *** Q×ƒ values are related to the lattice energy and grain *** temperature coefficient of resonance frequency has been analyzed using bond *** the Yb_(x)Ce_(1-x)O_(2-0.5x)(x=0.5-0.8)ceramics are multiple phases,the microwave dielectric properties are associated with the phase composition and grain growth.

关键词： structure stability bond ionicity oxygen vacancy electronic localization function(ELF)