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What j.b can a bug give?A controversy over the arsenic-guzzling bacterium cultured by NASA

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Protein & Cell 2011年第4期2卷 261-263页

作者： Mingwei Sun Christopher j.Vavricka Baoli zhu CAS Key Laboratory of Pathogenic Microbiology and Immunology Institute of MicrobiologyChinese Academy of Sciences(CASPMI)Beijing 100101China College of Life Sciences University of Science and Technology of ChinaHefei 230027China

The mysteries of life’s evolution on our planet drive us to explore the limits of *** forms on Earth as we know are composed of six essential elements:carbon,hydrogen,oxygen,nitrogen,sulfur and ***,a recently published research work funded by the National Aeronautics and Space Administration(NASA),USA,has almost shaken the fundamental knowledge about what is life made of on *** research team led by NASA astrobiologist Felisa Wolfe-Simon described a microbe isolated from California’s Mono Lake that could sustain its growth by using toxic chemical arsenic(As)instead of phosphorus(P).This surprising discovery was published online by Science Express on December 2 last year(Wolfe-Simon et al.,2010,online).If the authors of the paper were right,we would have to expand our definition of life on this *** arsenic-bug they grew was dubbed GFAj.1,which interestingly stands for“Give Felisa A j.b.”

关键词： bug planet Express

Roles of SO_2 oxidation in new particle formation events

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j.urnal of Environmental Sciences 2015年第4期27卷 90-101页

作者： He Meng Yuj.ao zhu Greg j.Evans Cheol-Heon j.ong Xiaohong Yao Key Lab of Marine Environmental Science and Ecology Ministry of Education Ocean University of China Southern Ontario Centre for Atmospheric Aerosol Research University of Toronto

The oxidation of SO2 is commonly regarded as a maj.r driver for new particle formation（NPF） in the atmosphere. In this study, we explored the connection between measured mixing ratio of SO2 and observed long-term（duration 〉 3 hr） and short-term（duration〈 1.5 hr） NPF events at a semi-urban site in Toronto. Apparent NPF rates（j.0） showed a moderate correlation with the concentration of sulfuric acid（[H2SO4]） calculated from the measured mixing ratio of SO2 in long-term NPF events and some short-term NPF events（Category I）（R^2= 0.66）. The exponent in the fitting line of j.0~ [H2SO4]nin these events was1.6. It was also found that SO2 mixing ratios varied a lot during long-term NPF events,leading to a significant variation of new particle counts. In the SO2-unexplained short-term NPF events（Category II）, analysis showed that new particles were formed aloft and then mixed down to the ground level. Further calculation results showed that sulfuric acid oxidized from SO2 probably made a negligible contribution to the growth of 〉 10 nm new particles.

关键词： Nucleation Particle growth Sulfuric acid Photochemical oxidation SO2

EFFECT OF SILICON ADDITION ON RECRYSTALLIZATION AND PHASE TRANSFORMATION BEHAVIOR OF HIGH-STRENGTH HOT-ROLLED TRIP STEEL

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Acta Metallurgica Sinica(English Letters) 2008年第3期21卷 163-168页

作者： L.j. zhu D. Wu X.M. Zhao College of Materials Science and Engineering Jilin University Changchun 130025 China The State Key Laboratory of Rolling Technology and Automation Northeastern University Shenyang110004 China

Because Si is a noncarbide forming element, a multiphase microstructure consisting of ferrite, bainite, and retained austenite, at room temperature, can be formed by controlling the thermomechanical process strictly. The cooling schedules must be restricted by the formation of pearlite and cementite. In the present article, a new integrated mathematical model for prediction of microstructure evolution during controlled rolling and controlled cooling is developed for a typical kind of low carbon Si-Mn TRIP steel, which consists of temperature simulation, recrystallization, and transformation models. The influence of Si contents has been thoroughly investigated. The calculated results indicate that Si retards recrystallization, restrains austenite grain growth as well as accelerates polygonal ferrite transformation.

关键词： TRIP steel Recrystallization Ferrite transformation Bainite transformation Silicon

Circulating turbulent fluidization-A new fluidization regime or j.st a transitional phenomenon

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Particuology 2010年第6期8卷 640-644页

作者： j.sse zhu Particle Technology Research Centre and Department of Chemical and Biochemical Engineering University of Western OntarioLondonOntarioN6A 5B9Canada

While circulating fluidized bed （CFB） reactor has many advantages over the more conventional turbulent fluidized bed （TFB） reactor, it does at least have one significant shortcoming-the rather dilute solids volume concentration in CFB reactor gives rise to less ideal reaction intensity. On the other hand, while having higher reaction intensity, TFB reactor has one fatal drawback of particle back-mixing, making it not suitable for certain reactions such as catalytic reaction where the catalyst requires frequent regeneration. This paper describes some key issues in the development of a circulating turbulent fluidized bed （CTFB） reactor that combines the advantages of both TFB and CFB, that is, to have the high reaction intensity as in TFB but and also to have a suppressed solids back-mixing as in CFB due to a continuous net upflow of solids flux through the bed. Experimental results show enough evidence to suggest that a new fluidization regime is formed, the characteristics of which appears to be distinct from those observed in a regular TFB and from those in either the bottom or the upper sections of regular CFB and/or high-density CFB （HDCFB）. Fundamentally, the difference is that particle-particle interaction （collision） dominates the motion of particles in CTFB and TFB, while gas-particle interaction （drag force） is the key element that determines the two phase flow in CFB including HDCFB.

关键词： Circulating-turbulent fluidized bed Flow regime Circulating-turbulent fluidizationTurbulent fluidized bed Circulating fluidized bed

IN SITU PROCESSING OF Al_(2)O_(3) WHISKERS REINFORCED Ti-Al INTERMETALLIC COMPOSITES

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Acta Metallurgica Sinica(English Letters) 2006年第6期19卷 432-440页

作者： F.Wang Z.K.Fan j.F.zhu School of Materials Science and Engineering Xi’an University of TechnologyXi’an 710048China School of Materials Science and Engineering Shaanxi University of Science and TechnologyXianyang 712081China

In situ Al2O3 whiskers reinforced Ti-Al intermetallic composites were fabricated at ~1200℃ by reaction sintering of cold-consolidated fillets consisting mainly of Ti, Al, and different additives. The phases and microstructures of the sintered composites were characterized using X-ray diffraction (XRD) and scanning electron microscopy (SEM) coupled with energy dispersive spectroscopy (EDS). The process of synthesis was investigated using differential thermal analysis (DTA). The effects of processing parameters and additives on the microstructures of the composites and the development of whisker were examined. It is found that the morphology of the whisker is strongly influenced by the additives, the exothermal reaction process, and the processing parameters.

关键词： in situ Al2O3 whisker Ti-Al intermetallic composite additive reaction process

真空加工处理对鲜食糯玉米淀粉结构和理化性质的影响

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食品工业科技 2025年第1期46卷 97-103页

作者：徐瑞航朱立斌朱丹魏文毅牛广财赵晨雨张玙璠黑龙江八一农垦大学食品学院黑龙江大庆163319 黑龙江省农产品加工工程技术研究中心黑龙江大庆163319 黑龙江八一农垦大学生命科学技术学院黑龙江大庆163319

为探究真空加工处理对鲜食糯玉米淀粉结构和理化性质的影响,以黄糯619和黑宝两个鲜食糯玉米品种为原料,通过扫描电子显微镜、X-射线衍射仪、傅里叶红外光谱仪、差示扫描量热仪和快速黏度分析仪等研究真空加工处理对鲜食糯玉米淀粉微观... 详细信息

为探究真空加工处理对鲜食糯玉米淀粉结构和理化性质的影响,以黄糯619和黑宝两个鲜食糯玉米品种为原料,通过扫描电子显微镜、X-射线衍射仪、傅里叶红外光谱仪、差示扫描量热仪和快速黏度分析仪等研究真空加工处理对鲜食糯玉米淀粉微观结构和理化性质的影响。结果表明:真空加工处理使黄糯619和黑宝2种鲜食糯玉米的直链淀粉含量显著升高(P<0.05),分别由5.39%和6.26%升高至8.52%和9.71%,支链淀粉含量显著降低(P<0.05),分别由94.61%和93.74%降低至91.48%和90.29%,淀粉颗粒破坏严重,淀粉的晶体类型和官能团结构没有改变,但相对结晶度分别降低了9.62%和9.41%;真空加工处理后,2种鲜食糯玉米淀粉的起始温度、峰值温度、终止温度和糊化焓值显著下降(P<0.05),淀粉的糊化温度、峰值黏度、最终黏度、衰减值、回生值显著下降(P<0.05),表明淀粉更容易发生糊化,抗老化能力增强。此外,真空加工处理使鲜食糯玉米淀粉的抗性淀粉(RS)转变为快消化淀粉(RDS)和慢消化淀粉(SDS),说明真空加工处理能够提高鲜食糯玉米淀粉的消化速率。本实验结果可以为鲜食糯玉米真空加工与利用提供理论依据。

关键词：鲜食糯玉米真空加工处理淀粉结构理化性质

Decorating crystalline YFe_(2-x)Al_(x) on the Mg_(60)La_(10)Ni_(20)Cu_(10) amorphous alloy as “hydrogen pump” to realize fast de/hydrogenation

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j.urnal of Materials Science & Technology 2024年第6期173卷 72-79页

作者： L.j.Huang H.Wang L.Z.Ouyang M.zhu H.j.Lin School of Materials Science and Engineering Key Laboratory of Advanced Energy Storage Materials of Guangdong ProvinceSouth China University of TechnologyGuangzhou 510641China Institute of Advanced Wear&Corrosion Resistance and Functional Materials Jinan UniversityGuangzhou 510632China

Mg-based amorphous alloys are one of the potential hydrogen storage materials but suffer from sluggish dehydrogenation/hydrogenation(de/hydrogenation)*** this work,as a new strategy,a hydrogen pump is built on the surface of amorphous alloys to solve this *** milling crystalline YFe_(2-x)Al_(x) hydrogen storage alloy with Mg_(60)La_(10)Ni_(20)Cu_(10) amorphous alloy,fine crystalline particles were seeded on amorphous alloy powder to form a“strawberry”*** to the TEM observation,a metallurgical bonding boundary formed between the Mg-based amorphous matrix and the Y-Fe-Al crystalline *** microstructure and de/hydrogenation kinetics investigation,the“hydrogen pump”effect of the seeded crystalline alloy was confirmed,which makes it much easier for the hydrogen to dissociate on and diffuse through the surface of the Mg-based amorphous *** such effect,the H absorption rate of Mg_(60)La_(10)Ni_(20)Cu_(10) amorphous alloy became almost eight times faster and it absorbs ~2.8 wt.% in 1 h at 130℃ under 4.5 MPa-H_(2).Further,fast hydrogenation can even achieve at 70℃ and the low-temperature dehydrogenation kinetics of the amorphous hydride can be also greatly *** present work proves that surface modification is of great importance for obtaining Mg-based amorphous alloy with ideal hydrogen storage performance.

关键词： Hydrogen storage Mg-based amorphous alloy Hydrogen pump Composite structure

1700 nm optical coherence microscopy enables minimally invasive,label-free,in vivo optical biopsy deep in the mouse brain

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Light(Science & Applications) 2021年第8期10卷 1507-1519页

作者： j.n zhu Hercules Rezende Freitas Izumi Maezawa Lee-way j.n Vivek j.Srinivasan Department of Biomedical Engineering University of California DavisDavisCA 95616USA. Department of Pathology and Laboratory Medicine University of California Davis Medical CenterSacramentoCA 95817USA. Department of Ophthalmology and Vision Science School of MedicineUniversity of California DavisSacramentoCA 95817USA. Department of Ophthalmology NYU Langone HealthNew YorkNY 10017USA. Department of Radiology NYU Langone HealthNew YorkNY 10016USA. Tech4Health Institute NYU Langone HealthNew YorkNY 10010USA

In vivo,minimally invasive microscopy in deep cortical and sub-cortical regions of the mouse brain has been *** address this challenge,we present an in vivo high numerical aperture optical coherence microscopy(OCM)approach that fully utilizes the water absorption window around 1700nm;where ballistic attenuation in the brain is *** issues,including detector noise,excess light source noise,chromatic dispersion,and the resolution-speckle tradeoff,are analyzed and *** through a thinned-skull preparation that preserves intracranial space,we present volumetric imaging of cytoarchitecture and myeloarchitecture across the entire depth of the mouse neocortex,and some sub-cortical *** an Alzheimer's disease model,we report that findings in superficial and deep cortical layers diverge,highlighting the importance of deep optical *** to other microscopic techniques,our 1700nm OCM approach achieves a unique combination of intrinsic contrast,minimal invasiveness,and high resolution for deep brain imaging.

关键词： biopsy superficial enable

Super-resolution image reconstruction based on three-step-training neural networks

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j.urnal of Systems Engineering and Electronics 2010年第6期21卷 934-940页

作者： Fuzhen zhu j.nzong Li Bing zhu Dongdong Ma Institute of Image Information Technology and Engineering Harbin Institute of Technology Heilongjiang 150001 R R. China

A new method of super-resolution image reconstruction is proposed, which uses a three-step-training error backpropagation neural network （BPNN） to realize the super-resolution reconstruction （SRR） of satellite image. The method is based on BPNN. First, three groups learning samples with different resolutions are obtained according to image observation model, and then vector mappings are respectively used to those three group learning samples to speed up the convergence of BPNN, at last, three times consecutive training are carried on the BPNN. Training samples used in each step are of higher resolution than those used in the previous steps, so the increasing weights store a great amount of information for SRR, and network performance and generalization ability are improved greatly. Simulation and generalization tests are carried on the well-trained three-step-training NN respectively, and the reconstruction results with higher resolution images verify the effectiveness and validity of this method.

关键词： image reconstruction super-resolution three-steptraining neural network BP algorithm vector mapping.