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Facile synthesis of intra-nanogap enhanced Raman tags with different shapes

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Nano Research 2024年第9期17卷 8415-8423页

作者： Sanjun Fan Brian T.Scarpitti Zhewen luo Abigail E.Smith Jian Ye Zachary D.Schultz department of Chemistry and Biochemistry The Ohio State UniversityColumbusOhio 43210USA School of Biomedical Engineering Shanghai Jiao Tong UniversityShanghai 200030China

Hot spot engineering in plasmonic nanostructures plays a significant role in surface-enhanced Raman scattering(SERS)for bioanalysis and cell ***,creating stable,reproducible,and strong SERS signals remains challenging due to the potential interference from surrounding chemicals and locating SERS-active analytes into hot-spot ***,we developed a straightforward approach to synthesize intra-gap nanoparticles encapsulating 4-nitrobenzenethiol(4-NBT)as a reporter molecule within these gaps to avoid outside *** made three kinds of intra-gap nanoparticles using nanorods,bipyramids,and nanospheres as cores,in which the nanorods based intra-gap nanoparticles exhibit the highest SERS *** advantage of our method is the ease of preparation of high-yield and stable intra-gap nanoparticles characterized by a short incubation time(10 min)with 4-NBT and quick synthesis without requiring an additional step to centrifuge for the purification of core *** intense localized field in the synthesized hot spots of these plasmonic gap nanostructures holds great promise as a SERS substrate for a broad range of quantitative optical applications.

关键词： hot spot engineering surface enhanced Raman scattering intra-gap nanoparticles 4-nitrobenzenethiol

theoretical analysis of tissue axial stretching model in elastography

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Progress in Natural Science:Materials International 2004年第5期 56-64页

作者： luo Jianwen, DING Chuxiong, BAI Jing and HE Ping (1. Depanment of Biomedical Engineering, Tsinghua university, Beijing 100084, China 2. department of Biomedical, Industrial, and Human Factors Engineering, Wright state university, Dayton, ohio 45435-0001, usa) department of Biomedical Engineering Tsinghua UniversityBeijing 100084China department of Biomedical Industrialand Human Factors EngineeringWright State UniversityDaytonOhio 45435-0001USA

the performance of axial displacement estimation in ultrasound elastography can be degraded by tissue lateral displacements, mainly because of the move-in and move-out of tissue scatterers. In our previous work, a tissue axial stretching model was proposed to separate the decorrelation effect induced by lateral displacements from other decorrelation sources. In this paper, the tissue axial stretching model is analyzed theoretically. the theoretical result in a closed form indicates that the peak value of the cross-correlation function between the pre- and post-compression echoes is determined mainly by the beam width, the beam position and the lateral strain. Computer simulations are carried out to verify the theoretical conclusion. the theoretical analysis and simulation results can help to understand more clearly the decorrelation effect of tissue lateral displacements and the 2-D spatial comprehensive cross-correlation method presented previously to reduce the decorrelation effect.

关键词： elastography decorrelation lateral displacements the cross-correlation function ultrasound.

A new approach for the aerobic oxidation of 5-hydroxymethylfurfural to 2,5-furandicarboxylic acid without using transition metal catalysts

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Journal of Energy Chemistry 2018年第1期27卷 243-249页

作者： Lu Zhang Xiaolan luo Yebo Li department of Food Agricultural and Biological EngineeringOhio Agricultural Research and Development CenterThe Ohio State University1680 Madison AvenueWoosterOH 44691-4096USA Quosar Energy Group 8600 E.Pleasant Valley RdIndependenceOH 44131USA

the organic compound 2,5-furandicarboxylic acid（FDCA） has been identified by the US department of Energy（DOE） as a valuable platform chemical for a wide range of industrial applications. Currently, the most popular route for FDCA synthesis is reported to be the oxidation of 5-hydroxymethylfurfural（HMF）by O_2 over the catalysis of noble metals（e.g., Au, Pt, Ru, and Pd）. However, the high costs of noble metal catalysts remain a major barrier for producing FDCA at an industrial scale. Herein, we report a transition metal-free synthesis strategy for the oxidation of HMF to FDCA under O_2 or ambient air. A simple but unprecedented process for the aerobic oxidation of HMF was carried out in organic solvents using only bases as the promoters. According to the high performance liquid chromatography（HPLC） analysis, excellent product yield（91%） was obtained in the presence of Naoh in dimethylformamide（DMF） at room temperature（25 ℃）. A plausible mechanism for the Naoh-promoted aerobic oxidation of HMF in DMF is also outlined in this paper. After the reaction, the sodium salt of FDCA particles were dispersed in the reaction mixture, making it possible for product separation and solvent reuse. the new HMF oxidation approach is expected to be a practical alternative to current ones, which depend on the use of noble metal catalysts.

关键词： Aerobic oxidation 5-Hydroxymethylfur fural2 5-Furandicarboxylic acid Sodium hydroxide Transition metal catalyst-free

three-dimensional visualization and quantification of microporosity in aluminum castings by X-ray micro-computed tomography

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Journal of Materials Science & Technology 2021年第6期65卷 99-107页

作者： Cheng Gu Yan Lu Alan A.luo department of Materials Science and Engineering The Ohio State University2041 College Rd N.ColumbusOhio 43210USA department of Integrated Systems Engineering The Ohio State University1971 NeilAve.ColumbusOhio 43210USA

Porosity is a major issue in solidification processing of metallic *** this work,wedge die casting experiments were designed to investigate the effect of cooling rate on microporosity in an aluminum alloy *** information including dendrites and porosity were measured and observed by optical microscopy and X-ray micro-computed tomography(XMCT).the effects of cooling rate on secondary dendrite arm spacing(SDAS)and porosity were *** relationship between SDAS and cooling rate was established and validated using a mathematical ***-dimensional(3-D)porosity information,including porosity percentage,pore volume,and pore number,was determined by *** the cooling rate decreasing from a lower to a higher position of the wedge die,the observed pore number decreases,the porosity percentage increases,and the equivalent pore radius *** of the pores was discussed as an empirical criterion to distinguish the types of *** different cooling rates,the larger the equivalent pore radius is,the lower the sphericity of the *** research suggests that XMCT is a useful tool to provide critical 3-D porosity information for integrated computational materials engineering(ICME)design and process optimization of solidification products.

关键词： X-ray computed tomography Casting micropore Quantitative evaluation Al alloy

Direct measurement of the break-out ^(19)F(p,γ)^(20)Ne reaction in the China Jinping underground laboratory(CJPL)

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Nuclear Science and Techniques 2024年第8期35卷 142-152页

作者： Yin‑Ji Chen Hao Zhang Li‑Yong Zhang Jian‑Jun He Richard James deBoer Michael Wiescher Alexander Heger David Kahl Jun Su Daniel Odell Xin‑Yue Li Jian‑Guo Wang Long Zhang Fu‑Qiang Cao Zhi‑Cheng Zhang Xin‑Zhi Jiang luo‑Huan Wang Zi‑Ming Li Lu‑Yang Song Liang‑Ting Sun Qi Wu Jia‑Qing Li Bao‑Qun Cui Li‑Hua Chen Rui‑Gang Ma Er‑Tao Li Gang Lian Yao‑De Sheng Zhi‑Hong Li Bing Guo Wei‑Ping Liu Key Laboratory of Beam Technology of the Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China department of Physics and Astronomy The Joint Institute for Nuclear AstrophysicsUniversity of Notre DameNotre DameIN 46556USA School of Physics and Astronomy Monash UniversityClaytonVIC 3800Australia Facility for Rare Isotope Beams Michigan State UniversityEast LansingMI 48824USA Institute of Nuclear and Particle Physics and department of Physics and Astronomy Ohio UniversityAthensOH 45701USA Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China China Institute of Atomic Energy Beijing 102413China College of Physics and Optoelectronic Engineering Shenzhen UniversityShenzhen 518060China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China College of Science Southern University of Science and TechnologyShenzhen 518055China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China Key Laboratory of Nuclear Physics and Ion‑Beam Application(MOE) Institute of Modern PhysicsFudan UniversityShanghai 200433China School of mathematics and Physics Handan UniversityHandan 056005China

Calcium production and the stellar evolution of first-generation stars remain fascinating mysteries in *** one possible nucleosynthesis scenario,break-out from the hot carbon–nitrogen–oxygen(HCNO)cycle was thought to be the source of the calcium observed in these oldest ***,according to the stellar modeling,a nearly tenfold increase in the thermonuclear rate ratio of the break-out ^(19)F(p,γ)^(20) Ne reaction with respect to the competing ^(19)F(p,α)^(16) O back-processing reaction is required to reproduce the observed calcium *** performed a direct measurement of this break-out reaction at the China Jinping underground *** measurement was performed down to the low-energy limit of E_(c.m.)=186 keV in the center-of-mass *** key resonance was observed at 225.2 keV for the first *** a temperature of approximately 0.1 GK,this new resonance enhanced the thermonuclear ^(19)F(p,γ)^(20) Ne rate by up to a factor of≈7.4,compared with the previously recommended NACRE *** is of particular interest to the study of the evolution of the first stars and implies a stronger breakdown in their“warm”CNO cycle through the ^(19)F(p,γ)^(20) Ne reaction than previously *** break-out resulted in the production of the calcium observed in the oldest stars,enhancing our understanding of the evolution of the first stars.

关键词： Nuclear astrophysics First stars Abundance of calcium Reaction cross section Reaction rate China Jinping underground laboratory(CJPL) JUNA

Constitutive behavior and processing maps of a new wrought magnesium alloy ZE20 (Mg-2Zn-0.2Ce)

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Journal of Magnesium and Alloys 2020年第1期8卷 111-126页

作者： Scott C.Sutton Alan A.luo department of Materials Science and Engineering The Ohio State UniversityColumbusOH 43210United States department of Integrated Systems Engineering The Ohio State UniversityColumbusOH 43210United States Mag Specialties Inc. DenverCO 80210USA

ZE20(Mg-2Zn-0.2Ce)^2 is a new wrought magnesium alloy with improved extrudability and mechanical properties[1].To understand the constitutive behavior and workability of this new alloy,Gleeble thermomechanical testing has been carried out in this *** flow stress behavior of ZE20 was investigated between 250℃–450℃ and 10^–3 s^–1–1.0 s^–1 in isothermal *** descriptions of the flow stress are provided.A new general approach at application of the extended Ludwik equation is demonstrated and was found to be more accurate than the hyperbolic sine Arrhenius model while having a similar number of model *** maps were developed based on the experimental results and are verified with microstructural investigation.A region of safe processing with non-basal texture and high activity of dynamic recrystallization(DRX)was found between 375℃ and 450℃,from 10^–1 s^–1 to 10^–2.5 s^–1.A region of potentially safe processing with annealing that is associated with shear band nucleation of non-basal grains was identified for temperatures as low as 300℃ and rates as high as 10^–1 s^–1.

关键词： Magnesium alloys thermomechanical processing Constitutive behavior Processing map Deformation mechanisms

Bimodal grain structure formation and strengthening mechanisms in Mg-Mn-Al-Ca extrusion alloys

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Journal of Magnesium and Alloys 2023年第12期11卷 4407-4419页

作者： Jianyue Zhang Peng Peng Qingshan Yang Alan A.luo department of Materials Science and Engineering The Ohio State UniversityColumbusOH 43210USA School of Metallurgy and Material Engineering Chongqing University of Science and TechnologyChongqing401331China department of Integrated Systems Engineering The Ohio State UniversityColumbusOhio 43210USA

the effects of small additions of calcium (0.1%and 0.5%~1) on the dynamic recrystallization behavior and mechanical properties of asextruded Mg-1Mn-0.5Al alloys were *** microalloying led to the formation of Al_(2)Ca in as-cast Mg-1Mn-0.5Al-0.1Ca alloy and both Mg_(2)Ca and Al_(2)Ca phases in Mg-1Mn-0.5Al-0.5Ca *** formed Al_(2)Ca particles were fractured during extrusion process and distributed at grain boundary along extrusion direction (ED).the Mg_(2)Ca phase was dynamically precipitated during extrusion process,hindering dislocation movement and reducing dislocation accumulation in low angle grain boundaries (LAGBs) and hindering the transformation of high density of LAGBs into high angle grain boundaries (HAGBs).therefore,a bimodal structure composed of fine dynamically recrystallized (DRXed) grains and coarse un DRXed regions was formed in Ca-microalloyed Mg-1Mn-0.5Al *** bimodal structure resulted in effective hetero-deformation-induced (HDI) ***,the fine grains in DRXed regions and the coarse grains in un DRXed regions and the dynamically precipitated Mg_(2)Ca phase significantly enhanced the tensile yield strength from 224 MPa in Mg-1Mn-0.5Al to335 MPa and 352 MPa in Mg-1Mn-0.5Al-0.1Ca and Mg-1Mn-0.5Al-0.5Ca,***,a yield point phenomenon was observed in as-extruded Mg-1Mn-0.5Al-x Ca alloys,more profound with 0.5%Ca addition,which was due to the formation of (■) extension twins in un DRXed regions.

关键词： Magnesium alloys Extrusion Dynamic precipitation Dynamic recrystallization Bimodal grain structure Mechanical properties

Towards high strength cast Mg-RE based alloys:Phase diagrams and strengthening mechanisms

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Journal of Magnesium and Alloys 2022年第6期10卷 1401-1427页

作者： Janet M.Meier Josh Caris Alan A.luo department of Materials Science and Engineering The Ohio State UniversityColumbusOH 43210USA Terves LLC EuclidOH 44117USA department of Integrated Systems Engineering The Ohio State UniversityColumbusOH 43210USA

Mg-rare earth(RE)based systems provide several important commercial alloys and many alloy development opportunities for high strength applications,especially in aerospace and defense *** phase diagrams,microstructure,and strengthening mechanisms of these multicomponent systems are very complex and often not well understood in *** have calculated phase diagrams of important binary,ternary,and multicomponent RE-containing alloy systems,using CALPHAD(CALculation of PHAse Diagrams).Based on these phase diagrams,this paper offers a critical overview on phase equilibria and strengthening mechanisms in these alloy systems,including precipitation,long period stacking order(LPSO),and other intermetallic *** review also summarized several promising Mg-RE based cast alloys in comparison with commercial WE54 and WE43 alloys;and explored new strategies for future alloy development for high strength *** is pointed out that the combination of precipitation and LPSO phases can lead to superior strength and ductility in Mg-RE based cast *** precipitates and LPSO phases can form a complex three-dimensional network that effectively impedes dislocation motion on the basal and non-basal *** LPSO phases can also prevent the coarsening of precipitates when they interact,thus providing good thermal stability at elevated *** research is needed to determine how the combination of these two types of phases can be used in alloy design and industrial scale applications.

关键词： Magnesium alloys Phase diagrams Precipitation strengthening Long period stacking order(LPSO) Alloy development CALPHAD

TIFA suppresses hepatocellular carcinoma progression via MALT1-dependent and-independent signaling pathways

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Signal Transduction and Targeted therapy 2016年第1期1卷 81-90页

作者： wenzhi Shen Renle Du Jun Li Xiaohe luo Shuangtao Zhao Antao Chang Wei Zhou Ruifang Gao Dehong luo Juan Wang Na Hao Yanhua Liu Yanan Chen Yunping luo Peiqing Sun Shengyong Yang Na luo Rong Xiang department of Immunology School of MedicineNankai UniversityTianjinChina International Joint Center for Biomedical Research of the Ministry of Education TianjinChina department of Immunology Institute of Basic Medical ScienceChinese Academy of Medical Science and Peking Union Medical CollegeBeijingChina department of Cancer Biology and Comprehensive Cancer Center Wake Forest University Medical CenterWinston-SalemNorth CarolinaUSA west China Hospital Molecular Medicine Research CentreState Key Lab BiotherapySichuan UniversityChengduChina

TIFA,also called T2BP,was first identified using yeast two-hybrid *** previous work showed that TIFA suppresses hepatocellular carcinoma(HCC)progression via apoptosis and cell cycle ***,the mechanism by which this TIFA suppression occurs remains *** we demonstrated that TIFA-induced apoptosis demonstrates two distinct time patterns(i.e.,at 48 h and 47 days)when TIFA reconstitution ***,we found that MALT1(a competitor of TIFA)plays a crucial role in short-duration TIFA *** this regard,MALT1 silencing with shRNA markedly enhances TIFA-induced apoptosis in vitro and in *** addition,TIFA overexpression triggers JNK and p38 activation in long-duration TIFA reconstitution through TRAF6 *** particular,JNK activation leads to TIFA-induced apoptosis while p38 activation governs TIFA-induced cell cycle arrest by p53-p21 signaling in vitro and in *** data suggest a novel mechanism by which TIFA suppresses HCC progression via both MALT1-dependent and MALT1-independent signaling *** may provide insights into a novel targets where HCC progression may be vulnerable to clinical treatment.

关键词： MALT1 markedly hepatocellular