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Microencapsulated β-carotene preparation using different drying treatments 被引量:2
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作者 Xiang-yu LI Mian-bin WU +4 位作者 Min XIAO Shu-huan LU Zhi-ming WANG Jian-ming YAO Li-rong YANG 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2019年第11期901-909,共9页
β-Carotene is one of the most abundant natural pigments in foods;however,usage of β-carotene is limited because of its instability.Microencapsulation techniques are usually applied to protect microencapsulated p-car... β-Carotene is one of the most abundant natural pigments in foods;however,usage of β-carotene is limited because of its instability.Microencapsulation techniques are usually applied to protect microencapsulated p-carotene from oxidization.In this study,β-carotene was microencapsulated using different drying processes:spray-drying,spray freeze-dryi ng,coati ng,and spray granulation.The properties of morphology,particle size,water con tent,thermal characteristic,and chemical stability have been explored and compared.Scanning electron microscopy measure?ments showed that the coated powder had a dense surface surro un ded by starch and suggested that the coati ng process gave a microencapsulated powder with the smallest bulk density and the best compressibility among the prepared powders.The chemical stabilities of microcapsules were evaluated during six months of storage at different temperatures.The coated powder had the highest mass fraction of β-carotene,which indicated that the coating process was superior to the three other drying processes. 展开更多
关键词 Β-CAROTENE microe ncapsulation SPRAY-DRYING Spray freeze-drying Coating Spray granulation
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Functionalize d 3D-printe d porous titanium scaffold induces in situ vascularized bone regeneration by orchestrating bone microenvironment 被引量:1
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作者 Bo Yuan Pin Liu +5 位作者 Rui Zhao Xiao Yang Zhanwen Xiao Kai Zhang Xiangdong Zhu Xingdong Zhang 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2023年第22期92-105,共14页
Titanium(Ti)and its alloys have been extensively explored for treating load-bearing bone defects.How-ever,high-stress shielding,weak osteogenic activity,and insufficient vascularization remain key chal-lenges for the ... Titanium(Ti)and its alloys have been extensively explored for treating load-bearing bone defects.How-ever,high-stress shielding,weak osteogenic activity,and insufficient vascularization remain key chal-lenges for the long-term clinical outcomes of Ti-based implants.Herein,inspired by structural and func-tional cues of bone regeneration,a silicon-doped nano-hydroxyapatite(nSiHA)/titanium dioxide(TiO_(2))composite coating with a hierarchical micro/nano-network structure is constructed on the surface of a 3D-printed porous Ti scaffold via a combined strategy of acid-alkali(AA)treatment and electrochemi-cal deposition technique,which not only endows the scaffold with excellent osteoinduction ability but can also effectively immobilize and release vascular endothelial growth factor(VEGF).The results of the in vitro cell experiments show that the functionalized Ti scaffold significantly promotes osteogenesis in bone marrow mesenchymal stem cells(BMSCs)and angiogenesis in human umbilical vein endothelial cells(HUVECs)by activating the extracellular signal-regulated protein kinase(ERK)and HIF-1αsignaling pathways.After being implanted into a rat femoral condyle defect model,the functionalized Ti scaffold can induce in situ vascularized bone regeneration by orchestrating the two coupled processes of angio-genesis and osteogenesis.These findings indicate that the functionalized Ti scaffold has great potential in bone tissue regeneration and is a promising candidate for load-bearing bone defect repair. 展开更多
关键词 Porous titanium 3D-printing Hierarchical micro/nano-structure Bone microenvironment VASCULARIZATION Bone regeneration
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美国MicroE圆光栅在数控转台和DDR电机领域的应用及特点 被引量:1
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作者 付耀斌 李书恒 《电子工业专用设备》 2012年第3期24-26,共3页
近年来,对精确自动测量转角的要求大大增长,作为自动测量仪器和装备的关键元件圆光栅及反馈系统的需求也日趋迫切。很多部门在精密加工、精密测量和自动控制等方面,使用圆光栅就可以实现自动测量、数显和数控。
关键词 DDR电机 数控转台 microe圆光栅
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IN-SITU REFLECTION MICROSCOPIC FTIR SPECTROELECTROCHEMISTRY AT MICRO-/ULTRAMICROELECTRODE
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作者 Xiang Qin LIN Zhi Li LI Laboratory of Electroanalytical Chemistry,Changchun Institute of Applied Chemistry,Chinese Academy of Sciences,Jilin 130022 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第12期1029-1032,共4页
An in-situ reflection ultramicroelectrode microscopic FTIR spectroelectrochemical cell was constructed and demonstrated by using hexacyanoferrate redox couple in aqueous sulphate solution.An excellent microscopic SNIF... An in-situ reflection ultramicroelectrode microscopic FTIR spectroelectrochemical cell was constructed and demonstrated by using hexacyanoferrate redox couple in aqueous sulphate solution.An excellent microscopic SNIFTIRS reflection spectra had been obtained with no difficulty of IR beam focusing.The cell is simple in construction and convenient for use,And it will have most of all advantages of micro-/ultramicroelectrode. 展开更多
关键词 FTIR In ULTRAmicroeLECTRODE IN-SITU REFLECTION MICROSCOPIC FTIR SPECTROELECTROCHEMISTRY AT MICRO AT
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美国MicroE微光栅编码器在直线电机及直接驱动领域的应用
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作者 牛怀新 高大智 《电子工业专用设备》 2008年第11期53-56,共4页
MicroE光栅编码器采用独特的光学系统,应用了大规模集成电路和FPGA技术,配合先进的软件算法,使其在同样分辨率的情况下做到尺寸最小,重量最轻,速度最快,安装误差要求最低;配合MicroE公司提供的PC端软件,客户可以自己定制编码器的分辨率... MicroE光栅编码器采用独特的光学系统,应用了大规模集成电路和FPGA技术,配合先进的软件算法,使其在同样分辨率的情况下做到尺寸最小,重量最轻,速度最快,安装误差要求最低;配合MicroE公司提供的PC端软件,客户可以自己定制编码器的分辨率和工作频率,方便了在不同场合的应用;MicroE编码器另一个显著的特点是同一读数头可以读取不同类型的光栅,适应金属和玻璃光栅,圆形和直线光栅。并通过几个典型设备的应用举例,说明了MicroE光栅编码器与直线电机配合使用的特点和效果。 展开更多
关键词 直线电机 光栅编码器 microe
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美国MicroE微光棚编码器在直线电机及直接驱动领域的应用
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作者 牛怀新 高大智 《伺服控制》 2008年第10期48-50,73,共4页
传统的光栅编码器在数控和伺服领域得到的了广泛的应用,但在直线电机和直接驱动领域受到了来自美国GSI集团公司MicroE光栅编码器的挑战。MicroE光栅编码器具有抗电磁干扰能力强、高速度、小尺寸和使用灵活方便的优势,近年来在直线电机... 传统的光栅编码器在数控和伺服领域得到的了广泛的应用,但在直线电机和直接驱动领域受到了来自美国GSI集团公司MicroE光栅编码器的挑战。MicroE光栅编码器具有抗电磁干扰能力强、高速度、小尺寸和使用灵活方便的优势,近年来在直线电机和直接驱动应用领域被广泛采用。本文从几个典型设备的应用,介绍MicroE光栅编码器与直线电机配合使用的特点和效果。包括IC封装测试设备、PCB贴片设备、激光加工设备等领域。 展开更多
关键词 直线电机 光栅编码器 microe
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Swarming Responsive Photonic Nanorobots for Motile-Targeting Microenvironmental Mapping and Mapping-Guided Photothermal Treatment 被引量:5
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作者 Luolin Li Zheng Yu +7 位作者 Jianfeng Liu Manyi Yang Gongpu Shi Ziqi Feng Wei Luo Huiru Ma Jianguo Guan Fangzhi Mou 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第9期205-223,共19页
Micro/nanorobots can propel and navigate in many hard-to-reach biological environments,and thus may bring revolutionary changes to biomedical research and applications.However,current MNRs lack the capability to colle... Micro/nanorobots can propel and navigate in many hard-to-reach biological environments,and thus may bring revolutionary changes to biomedical research and applications.However,current MNRs lack the capability to collectively perceive and report physicochemical changes in unknown microenvironments.Here we propose to develop swarming responsive photonic nanorobots that can map local physicochemical conditions on the fly and further guide localized photothermal treatment.The RPNRs consist of a photonic nanochain of periodically-assembled magnetic Fe_(3)O_(4)nanoparticles encapsulated in a responsive hydrogel shell,and show multiple integrated functions,including energetic magnetically-driven swarming motions,bright stimuli-responsive structural colors,and photothermal conversion.Thus,they can actively navigate in complex environments utilizing their controllable swarming motions,then visualize unknown targets(e.g.,tumor lesion)by collectively mapping out local abnormal physicochemical conditions(e.g.,pH,temperature,or glucose concentra-tion)via their responsive structural colors,and further guide external light irradiation to initiate localized photothermal treatment.This work facilitates the development of intelligent motile nanosensors and versatile multifunctional nanotheranostics for cancer and inflam-matory diseases. 展开更多
关键词 Micro/nanorobots Collective behaviors Responsive photonic crystals On-the-fly sensing Photothermal therapy
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Laser-assisted deposition of Cu bumps for microelectronic packaging 被引量:1
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作者 Won-Seok CHOI Joohan KIM 《中国有色金属学会会刊:英文版》 CSCD 2012年第S3期683-687,共5页
Cu bump was transferred using a focused laser pulse for microelectronic packaging.An Nd:YAG laser pulse (maximum energy of 500 mJ;wavelength of 1064 nm;fluences of 0.4-2.1 kJ/cm2) was irradiated on a sacrificial absor... Cu bump was transferred using a focused laser pulse for microelectronic packaging.An Nd:YAG laser pulse (maximum energy of 500 mJ;wavelength of 1064 nm;fluences of 0.4-2.1 kJ/cm2) was irradiated on a sacrificial absorption layer with copper coating.The focused laser beam induced plasma between the semi-transparent donor slide and the sacrificial layer,causing a shock wave.The shock wave pressure pushed the Cu layer and transferred material to deposit a bump on substrate.A beam-shaper was used to produce uniform pressure at the interface to reduce fragmentation of the transferred material on the substrate.The calculated shock wave pressure with respect to laser fluence was 1-3 GPa.A Cu bump of diameter of 200 μm was successfully deposited at laser fluence of 0.6 kJ/cm 2.The pressure control at the sacrificial layer using a laser pulse was critical to produce a bump with less fragmentation.The technique can be applied to forming Cu bump for an interconnecting process in electronics. 展开更多
关键词 LASER induced FORWARD transfer BUMP deposition ND:YAG PULSED LASER micro system packaging beam SHAPING
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Determination of Melamine in Fresh Milk by Electrochemistry with Solid Phase Microextraction at Bismuthyl Chloride Modified Graphite Epoxy Composite Electrode
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作者 Yongchun Zhu Yanjia Zhang +3 位作者 Jingyi Li Yanli Han Guobin Dong Hongbo Zhang 《American Journal of Analytical Chemistry》 2011年第5期612-618,共7页
Melamine as an important chemical raw material and a harmful additive in foods has attracted many people’s attention. In the present paper, The graphite-epoxy composited solid phase electrode was modified with bismut... Melamine as an important chemical raw material and a harmful additive in foods has attracted many people’s attention. In the present paper, The graphite-epoxy composited solid phase electrode was modified with bismuth layer by cyclic voltammetric deposition of bismuth from Bi(NO3)3 aqueous solution including 0.10 M HNO3, and hydrolyzed into micro bismuthyl chloride on-sites. Melamine in fresh milk was extracted with solid phase micro-extraction on the bismuthyl chloride modified graphite-epoxy composited solid electrode. The adsorption of melamine on bismuthyl chloride particle surfaces follows a Freundlich adsorption model, and results in the decrease of the reduction peak current of bismuth in bismuthyl chloride, and determined by differential pulse voltammetry from fresh milk in a larger concentration range of 10–4 ? 10–12 M with detection limit of 2.5 ? 10–12 M and relative standard deviation of 2.7%. The method is sensitive, convenient and was applied in the detection of melamine in fresh milk with relative deviation of 4.2% in content of 0.45 mg/kg melamine in the fresh milk. 展开更多
关键词 MELAMINE Bismuthyl CHLORIDE Modified ELECTRODE Adsorption Differential PULSE VOLTAMMETRY Solid Phase Micro Extraction
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u-Nav Microelectronics公司在便携式GPS系统中选用Tensilica公司Xtensa处理器内核
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《电子工业专用设备》 2006年第4期11-11,共1页
美国加州Santa讯:作为能够为SoC自动设计实现针对应用而优化定制的可配置处理器的Tensilica公司日前宣布,领先于世界超低功耗全球定位系统(GPS)的u-Nav Microelectronics公司选择Xtensa可配置处理器内核用于下一代GPS便携设备的设... 美国加州Santa讯:作为能够为SoC自动设计实现针对应用而优化定制的可配置处理器的Tensilica公司日前宣布,领先于世界超低功耗全球定位系统(GPS)的u-Nav Microelectronics公司选择Xtensa可配置处理器内核用于下一代GPS便携设备的设计,该设计将面向诸如移动无线手持设备和消费类电子的便携式应用。 展开更多
关键词 electronics公司 Tensilica公司 XTENSA 便携式应用 GPS系统 Micro 处理器 内核 设计实现 全球定位系统
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Multi-sized microelectrode array coupled with micro-electroporation for effective recording of intracellular action potential
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作者 Xingyuan Xu Zhengjie Liu +10 位作者 Jing Liu Chuanjie Yao Xi Chen Xinshuo Huang Shuang Huang Peng Shi Mingqiang Li Li Wang Yu Tao Hui-jiuan Chen Xi Xie 《Microsystems & Nanoengineering》 2025年第3期343-360,共18页
Microelectrode arrays(MEAs)are essential tools for studying the extracellular electrophysiology of cardiomyocytes in a multi-channel format.However,they typically lack the capability to record intracellular action pot... Microelectrode arrays(MEAs)are essential tools for studying the extracellular electrophysiology of cardiomyocytes in a multi-channel format.However,they typically lack the capability to record intracellular action potentials(APs).Recent studies have relied on costly fabrication of high-resolution microelectrodes combined with electroporation for intracellular recordings,but the impact of microelectrode size on micro-electroporation and the quality of intracellular signal acquisition has yet to be explored.Understanding these effects could facilitate the design of microelectrodes of various sizes to enable lower-cost manufacturing processes.In this study,we investigated the influence of microelectrode size on intracellular AP parameters and recording metrics post-micro-electroporation through simulations and experiments.We fabricated microelectrodes of different sizes using standard photolithography techniques to record cardiomyocyte APs from various culture environments with coupled micro-electroporation.Our findings indicate that larger microelectrodes generally recorded electrophysiological signals with higher amplitude and better signal-to-noise ratios,while smaller electrodes exhibited higher perforation efficiency,AP duration,and single-cell signal ratios.This work demonstrates that the micro-electroporation technique can be applied to larger microelectrodes for intracellular recordings,rather than being limited to high-resolution designs.This approach may provide new opportunities for fabricating microelectrodes using alternative low-cost manufacturing techniques for high-quality intracellular AP recordings. 展开更多
关键词 microelectrode arrays meas studying extracellular electrophysiology microeLECTRODE micro electroporation record intracellular action potentials aps recent intracellular signal acquisition CARDIOMYOCYTE intracellular recordingsbut
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Automated and collision-free navigation of multiple micro-objects in obstacle-dense microenvironments using optoelectronic tweezers
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作者 Lixiang Zheng Gong Li +13 位作者 Henan Du Zonghao Li Bingrui Xu Fan Yang Yanan Mao Jing Wei Hainan Xie Wei Xie Rongxin Fu Na Liu Shuailong Zhang Lianqing Liu Wen Jung Li Yu Sun 《Microsystems & Nanoengineering》 2025年第2期155-167,共13页
Automated parallel manipulation of multiple micro-objects with optoelectronic tweezers(OET)has brought significant research interests recently.However,the parallel manipulation of multiple objects in complex obstacle-... Automated parallel manipulation of multiple micro-objects with optoelectronic tweezers(OET)has brought significant research interests recently.However,the parallel manipulation of multiple objects in complex obstacle-dense microenvironment using OET technology based on negative dielectrophoresis(nDEP)remain a big technical challenge.In this work,we proposed an adaptive light pattern design strategy to achieve automated parallel OET manipulation of multiple micro-objects and navigate them through obstacles to target positions with high precision and no collision.We first developed a multi-micro-object parallel manipulation OET system,capable of simultaneous image processing and microparticles path planning.To overcome microparticle collisions caused by overlapping light patterns,we employed a novel adaptive light pattern design that can dynamically adjust the layout of overlapping light patterns according to surrounding environment,ensuring enough space for each microparticle and preventing unintended escapes from the OET trap.The efficacy of this approach has been verified through systematic simulations and experiments.Utilizing this strategy,multiple polystyrene microparticles were autonomously navigated through obstacles and microchannels to their intended destinations,demonstrating the strategy’s effectiveness and potential for automated parallel micromanipulation of multiple microparticles in complex and confined microenvironments. 展开更多
关键词 optoelectronic tweezers oet negative dielectrophoresis ndep remain adaptive light pattern design strategy manipulation multiple objects automated navigation obstacle dense microenvironments collision free micro objects
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Multi-channel microelectrode arrays for detection of single-cell level neural information in the hippocampus CA1 under general anesthesia induced by low-dose isoflurane 被引量:1
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作者 Ruilin Hu Penghui Fan +9 位作者 Yiding Wang Jin Shan Luyi Jing Wei Xu Fan Mo Mixia Wang Yan Luo Ying Wang Xinxia Cai Jinping Luo 《Fundamental Research》 2025年第1期72-81,共10页
Timely monitoring of anesthesia status during surgery is important to prevent an overdose of isoflurane anesthesia.Therefore,in-depth studies of the neural mechanisms of anesthetics are warranted.Hippocampal CA1 plays... Timely monitoring of anesthesia status during surgery is important to prevent an overdose of isoflurane anesthesia.Therefore,in-depth studies of the neural mechanisms of anesthetics are warranted.Hippocampal CA1 plays an important role during anesthesia.Currently,a high spatiotemporal resolution microdevice technology for the accurate detection of deep brain nuclei is lacking.In this research,four-shank 32-channel implantable microelectrode arrays(MEAs)were developed for the real-time recording of single-cell level neural information in rat hippocampal CA1.Platinum nanoparticles were modified onto the microelectrodes to substantially enhance the electrical properties of the microelectrode arrays.The modified MEAs exhibited low impedance(11.5±1 kΩ)and small phase delay(-18.5°±2.54°),which enabled the MEAs to record single-cell level neural information with a high signal-to-noise ratio.The MEAs were implanted into the CA1 nuclei of the anesthetized rats,and the electrophysiological signals were recorded under different degrees of anesthesia mediated by low-dose concentrations of isoflurane.The recorded signals were analyzed in depth.Isoflurane caused an inhibition of spike firing rate in hippocampal CA1 neurons,while inducing low-frequency oscillations in CA1,thus enhancing the low-frequency power of local field potentials.In this manner,the spike firing rate and the power of local field potentials in CA1 could characterize the degree of isoflurane anesthesia.The present study provides a technical tool to study the neural mechanisms of isoflurane anesthesia and a research method for monitoring the depth of isoflurane anesthesia in clinical practice. 展开更多
关键词 Micro electrode array Hippocampal CA1 Isoflurane anesthesia SPIKE Local field potentials
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Determination of organochlorine pesticides from juice samples using magnetic biochar-based dispersive micro-solid phase extraction in combination with dispersive liquid-liquid microextraction 被引量:1
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作者 Kero Assefa Ago Shimeles Addisu Kitte Abera Gure 《Emerging Contaminants》 CSCD 2024年第1期126-138,共13页
Analysis of pesticide residue levels in juice beverages is important to ensure safe consumption and avoid global trade concerns associated to pesticide contaminations.A simple,inexpensive and effective method was deve... Analysis of pesticide residue levels in juice beverages is important to ensure safe consumption and avoid global trade concerns associated to pesticide contaminations.A simple,inexpensive and effective method was developed for the determination of organochlorine pesticides(OCPs)in bottled juice drinks using GC-MS.Sample pretreatment was performed using dispersive solid-phase microextraction(D-μ-SPE)for matrix desorption and dispersive liquid-liquid microextraction(DLLME)for analyte enrichment.In this study,an affordable and effective sorbent for the adsorption of OCPs from juice samples was synthesized from avocado seeds mixed with magnetic precursors for D-μSPE.The ground avocado seeds combined with a magnetic precursor nanocomposite were characterized using various instruments including scanning electron microscopy(SEM),X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTIR),and Brunauer-Emmett-Teller(BET)analysis.The solution obtained from D-μ-SPE desorption was used as a dispersant for the subsequent DLLME,which made the combination of D-μ-SPE with DLLME much easier.The effectiveness of the method was enhanced by optimizing the influential parameters in both D-μ-SPE and DLLME.Then after,the optimal values were determined for the real sample analysis.Accordingly,there was good linear dynamic range with a coefficient of determination(r2)≥0.9989.The limit of detection and quantification were 0.02–0.69 and 0.06–2.10 ng/L respectively.The method showed high enrichment factors ranging from 96 to 313 with recoveries of 87–100%.Intraday and interday precisions were≤4%.Compared with other reported methods,this method is a one-step,simple,cheap,fast,and environmentally friendly alternative and straightforward method for adsorbing organochlorine pesticides from sample solutions.These results demonstrates the high potential of the proposed method for the extraction and cleanup of contaminants in selected juices and other related samples. 展开更多
关键词 Dispersive micro solid phase extraction Dispersive liquid-liquid microextraction Juice samples Magnetic biochar Organochlorine pesticides Gas chromatography-mass spectrometry
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High-throughput structure determination of polycrystalline functional materials:a platform for automated 3DED/MicroED data collection
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作者 Zhenghan Zhang Zhengyin Liang +2 位作者 Chao Ma Cong Lin Jian Li 《Science China Chemistry》 SCIE EI CAS CSCD 2024年第12期4158-4166,共9页
Structure determination plays the most crucial role in the discovery of novel functional materials,because only by knowing the intrinsic structures can we accurately and completely understand their properties and appl... Structure determination plays the most crucial role in the discovery of novel functional materials,because only by knowing the intrinsic structures can we accurately and completely understand their properties and applications.However,most new materials are obtained in polycrystalline form or even as mixtures with multiple phases when first synthesized,presenting significant challenges in their structure determination and phase elucidation.Fortunately,the developed three-dimensional electron diffraction(3DED/MicroED)has provided a promising solution to overcome these challenges.In this study,we have constructed a state-of-the-art 3DED/MicroED data acquisition equipment by integrating a hybrid-pixel detector with a script developed for Serial EM,and thus successfully developed an automated 3DED/MicroED method for the high-throughput structure determination.To demonstrate its effectiveness,a multiphase sample with complex porous structures is employed,showcasing that individual phases and their structures can be identified and determined,respectively.One remarkable finding is the identification of an impurity metal-organic framework(MOF)that is completely invisible to traditional powder X-ray diffraction in a supposedly“pure”commercial MOF sample.Additionally,our method also enables the atomic-resolution structure determination of flexible covalent organic framework materials,which are highly sensitive to electron beams.Moreover,a new microporous aluminoborate is discovered using this rapid structure determination method.These experimental results highlight the enormous potential of our 3DED/MicroED method in the field of new materials discovery,offering a powerful tool for the structure determination of polycrystalline functional materials. 展开更多
关键词 3DED/microeD high-throughput structure determination mixed phase porous materials
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MicroED as a powerful technique for the structure determination of complex porous materials
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作者 Chao Ma Cong Lin Jian Li 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2024年第3期41-54,共14页
Porous materials have garnered significant attention in recent years.Understanding the intrinsic relationship between their structures and properties requires precise knowledge of their atomic structures.Single-crysta... Porous materials have garnered significant attention in recent years.Understanding the intrinsic relationship between their structures and properties requires precise knowledge of their atomic structures.Single-crystal X-ray diffraction(SCXRD)has traditionally been the primary method for elucidating such structures,but it demands large,high-quality crystals,often exceeding 5μm in size.The growth of these crystals can be a time-consuming process,especially for one-and two-dimensional materials.To explore structures at the nanoscale,MicroED(microcrystal electron diffraction(ED))offers unprecedented insights into the realm of nanomaterials.This revolutionary technique enables researchers to uncover intricate details within nanoscale structures,promising to reshape our fundamental understanding of materials.In this review,we delve into the applications of MicroED in the study of various porous materials,including zeolites,metal-organic frameworks(MOFs),and covalent organic frameworks(COFs).We emphasize the pivotal role of MicroED in nanomaterial characterization,enabling precise crystallographic analysis and phase identification. 展开更多
关键词 Atomic structure microeD Porous materials Three-dimensional electron diffraction
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Tunable Optical Metamaterial Enables Steganography,Rewriting,and Multilevel Information Storage
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作者 Jianchen Zheng Yuzhao Zhang +7 位作者 Haibo Yu Jingang Wang Hongji Guo Ye Qiu Xiaoduo Wang Yu Feng Lianqing Liu Wen Jung Li 《Nano-Micro Letters》 2026年第2期553-568,共16页
In the realm of secure information storage,optical encryption has emerged as a vital technique,particularly with the miniaturization of encryption devices.However,many existing systems lack the necessary reconfigurabi... In the realm of secure information storage,optical encryption has emerged as a vital technique,particularly with the miniaturization of encryption devices.However,many existing systems lack the necessary reconfigurability and dynamic functionality.This study presents a novel approach through the development of dynamic optical-to-chemical energy conversion metamaterials,which enable enhanced steganography and multilevel information storage.We introduce a micro-dynamic multiple encryption device that leverages programmable optical properties in coumarin-based metamaterials,achieved through a direct laser writing grayscale gradient strategy.This methodology allows for the dynamic regulation of photoluminescent characteristics and cross-linking networks,facilitating innovative steganographic techniques under varying light conditions.The integration of a multi-optical field control system enables real-time adjustments to the material’s properties,enhancing the device’s reconfigurability and storage capabilities.Our findings underscore the potential of these metamaterials in advancing the field of microscale optical encryption,paving the way for future applications in dynamic storage and information security. 展开更多
关键词 Micro/nano-device Optical encryption METAMATERIALS Photoluminescence 4D printing
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Superelastic and Washable Micro/Nanofibrous Sponges Based on Biomimetic Helical Fibers for Efficient Thermal Insulation
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作者 Fengjin Yang Zhifei Wang +7 位作者 Wei Zhang Sai Wang Yi‑Tao Liu Fei Wang Roman ASurmenev Jianyong Yu Shichao Zhang Bin Ding 《Nano-Micro Letters》 2026年第2期170-182,共13页
Extreme cold weather seriously harms human thermoregulatory system,necessitating high-performance insulating garments to maintain body temperature.However,as the core insulating layer,advanced fibrous materials always... Extreme cold weather seriously harms human thermoregulatory system,necessitating high-performance insulating garments to maintain body temperature.However,as the core insulating layer,advanced fibrous materials always struggle to balance mechanical properties and thermal insulation,resulting in their inability to meet the demands for both washing resistance and personal protection.Herein,inspired by the natural spring-like structures of cucumber tendrils,a superelastic and washable micro/nanofibrous sponge(MNFS)based on biomimetic helical fibers is directly prepared utilizing multiple-jet electrospinning technology for high-performance thermal insulation.By regulating the conductivity of polyvinylidene fluoride solution,multiple-jet ejection and multiple-stage whipping of jets are achieved,and further control of phase separation rates enables the rapid solidification of jets to form spring-like helical fibers,which are directly entangled to assemble MNFS.The resulting MNFS exhibits superelasticity that can withstand large tensile strain(200%),1000 cyclic tensile or compression deformations,and retain good resilience even in liquid nitrogen(-196℃).Furthermore,the MNFS shows efficient thermal insulation with low thermal conductivity(24.85 mW m^(-1)K^(-1)),close to the value of dry air,and remains structural stability even after cyclic washing.This work offers new possibilities for advanced fibrous sponges in transportation,environmental,and energy applications. 展开更多
关键词 ELECTROSPINNING Micro/nanofibrous sponge Hierarchical structure SUPERELASTICITY Thermal insulation
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Correction: Optimizing Exciton and Charge-Carrier Behavior in Thick-Film Organic Photovoltaics: A Comprehensive Review
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作者 Lu Wei Yaxin Yang +2 位作者 Lingling Zhan Shouchun Yin Hongzheng Chen 《Nano-Micro Letters》 2026年第1期608-608,共1页
Correction to:Nano-Micro Letters(2026)18:10.https://doi.org/10.1007/s40820-025-01852-8 Following publication of the original article[1],the authors reported that the last author’s name was inadvertently misspelled.Th... Correction to:Nano-Micro Letters(2026)18:10.https://doi.org/10.1007/s40820-025-01852-8 Following publication of the original article[1],the authors reported that the last author’s name was inadvertently misspelled.The published version showed“Hongzhen Chen”,whereas the correct spelling should be“Hongzheng Chen”.The correct author name has been provided in this Correction,and the original article[1]has been corrected. 展开更多
关键词 charge carrier behavior exciton behavior comprehensive review thick film organic photovoltaics nano micro letters
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CO_(2)nanobubble-enhanced cement-fly ash backfill:Optimizing aggregate gradation and microstructure
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作者 Xiaoxiao Cao Haoyan Lyu +4 位作者 Yanlong Chen Jiangyu Wu Hideki Shimada Takashi Sasaoka Akihiro Hamanaka 《International Journal of Minerals,Metallurgy and Materials》 2026年第1期129-140,共12页
Mine filling materials urgently need to improve mechanical properties and achieve low-carbon transformation.This study explores the mechanism of the synergistic effect of optimizing aggregate fractal grading and intro... Mine filling materials urgently need to improve mechanical properties and achieve low-carbon transformation.This study explores the mechanism of the synergistic effect of optimizing aggregate fractal grading and introducing CO_(2)nanobubble technology to improve the performance of cement-fly ash-based backfill materials(CFB).The properties including fluidity,setting time,uniaxial compressive strength,elastic modulus,porosity,microstructure and CO_(2)storage performance were systematically studied through methods such as fluidity evaluation,time test,uniaxial compression test,mercury intrusion porosimetry(MIP),scanning electron microscopy-energy dispersive spectroscopy analysis(SEM-EDS),and thermogravimetric-differential thermogravimetric analysis(TG-DTG).The experimental results show that the density and strength of the material are significantly improved under the synergistic effect of fractal dimension and CO_(2)nanobubbles.When the fractal dimension reaches 2.65,the mass ratio of coarse and fine aggregates reaches the optimal balance,and the structural density is greatly improved at the same time.At this time,the uniaxial compressive strength and elastic modulus reach their peak values,with increases of up to 13.46%and 27.47%,respectively.CO_(2)nanobubbles enhance the material properties by promoting hydration reaction and carbonization.At the microscopic level,CO_(2)nanobubble water promotes the formation of C-S-H(hydrated calcium silicate),C-A-S-H(hydrated calcium aluminium silicate)gel and CaCO_(3),which is the main way to enhance the performance.Thermogravimetric studies have shown that when the fractal dimension is 2.65,the dehydration of hydration products and the decarbonization process of CaCO_(3)are most obvious,and CO_(2)nanobubble water promotes the carbonization reaction,making it surpass the natural state.The CO_(2)sequestration quality of cement-fly ash-based materials treated with CO_(2)nanobubble water at different fractal dimensions increased by 12.4wt%to 99.8wt%.The results not only provide scientific insights for the design and implementation of low-carbon filling materials,but also provide a solid theoretical basis for strengthening green mining practices and promoting sustainable resource utilization. 展开更多
关键词 cement-fly ash-based backfill CO_(2)nanobubble fractal dimension macro and micro performance carbon sequestration
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