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Three-dimensional morphological and fluorescent imaging of zebrafish with a continuous-rotational light-sheet microscope
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作者 Dongmin Zhang Guang Yang +3 位作者 Yao Tan Chong Chen Jie Zhang Hui Li 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2024年第2期59-66,共8页
Light-sheet fluorescence microscopy(LSFM)has been widely used to image the three-dimensional(3D)structures and functions of various millimeter-size bio-specimen such as zebrafish.However,the sample adsorption and scat... Light-sheet fluorescence microscopy(LSFM)has been widely used to image the three-dimensional(3D)structures and functions of various millimeter-size bio-specimen such as zebrafish.However,the sample adsorption and scattering cause shading of the light-sheet illumination,preventing the even 3D image of thick samples.Herein,we report a continuous-rotational light-sheet microscope(CR-LSM)that enables simultaneous 3D bright-field and fluorescence imaging.With a high-accuracy rotational stage,CR-LSM records the outline projections and the fluorescent images of the sample at multiple rotation angles.Then,3D morphology and fluorescent structure were reconstructed with a developed algorithm.Using CR-LSM,zebrafish’s whole-fish contour and blood vessel structures were obtained simultaneously. 展开更多
关键词 Light-sheet microscope zebrafish blood vessels MORPHOLOGY
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Constructing Electron Microscope Labs: Challenges and Solutions
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作者 Limei Cha Markus Walkling-Ribeiro +2 位作者 Zhenxi Guo Yaron Kauffman Constance Van Horne 《Journal of Building Construction and Planning Research》 2024年第3期53-68,共16页
The construction of advanced laboratories for precision instruments, such as electron microscopes, involves unique challenges that are influenced by the specific environmental conditions required for optimal functiona... The construction of advanced laboratories for precision instruments, such as electron microscopes, involves unique challenges that are influenced by the specific environmental conditions required for optimal functionality. These include mitigating interference from magnetic fields and vibrations, which are critical for maintaining the precision and accuracy of the instruments used. This study aims to offer enhanced project management strategies and detailed construction solutions that address the environmental and technical needs specific to electron microscopy labs, thereby facilitating effective lab operations and extending the lifecycle of high-end precision instruments. Case studies of existing laboratory constructions, onsite investigations, and comprehensive reviews of the technical and environmental requirements provide the basis for a best practice for constructing sophisticated electron microscopy labs. The approach integrates both pre-construction planning and post-construction adjustments to create optimal operational environments. The findings suggest that successful lab constructions are those that incorporate thorough onsite assessments, strategic location choices, and the use of advanced construction materials and techniques specifically designed to counteract environmental challenges like magnetic and vibration interferences. Actionable guidelines for both planning and executing the construction of electron microscope labs highlighted in this tutorial are intended as an important resource to troubleshoot or upgrade existing lab facilities and to consult in preparation of future lab construction projects. 展开更多
关键词 Laboratory Construction Development Strategies MANAGEMENT Case Study Electron microscope Magnetic Shielding VIBRATION
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Deep learning method for cell count from transmitted-light microscope
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作者 Mengyang Lu Wei Shi +3 位作者 Zhengfen Jiang Boyi Li Dean Ta Xin Liu 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2023年第5期115-127,共13页
Automatic cell counting provides an effective tool for medical research and diagnosis.Currently,cell counting can be completed by transmitted-light microscope,however,it requires expert knowledge and the counting accu... Automatic cell counting provides an effective tool for medical research and diagnosis.Currently,cell counting can be completed by transmitted-light microscope,however,it requires expert knowledge and the counting accuracy which is unsatisfied for overlapped cells.Further,the image-translation-based detection method has been proposed and the potential has been shown to accomplish cell counting from transmitted-light microscope,automatically and effectively.In this work,a new deep-learning(DL)-based two-stage detection method(cGAN-YOLO)is designed to further enhance the performance of cell counting,which is achieved by combining a DL-based fluorescent image translation model and a DL-based cell detection model.The various results show that cGAN-YOLO can effectively detect and count some different types of cells from the acquired transmitted-light microscope images.Compared with the previously reported YOLO-based one-stage detection method,high recognition accuracy(RA)is achieved by the cGAN-YOLO method,with an improvement of 29.80%.Furthermore,we can also observe that cGAN-YOLO obtains an improvement of 12.11%in RA compared with the previously reported image-translation-based detection method.In a word,cGAN-YOLO makes it possible to implement cell counting directly from the experimental acquired transmitted-light microscopy images with high flexibility and performance,which extends the applicability in clinical research. 展开更多
关键词 Automatic cell counting transmitted-light microscope deep-learning fluorescent image translation.
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Comparative Alpha Tracks Counting Using an Optical Microscope and a Spark Counter
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作者 Dabo S. I. Agba Ponaho Kezo Issa Konaté 《Detection》 2023年第2期7-18,共12页
In the metrology of radon, an environmental lung carcinogen, the integrated measurements necessary for epidemiological studies are made very often using the tracks detector LR 115 type 2. For dosimetric analysis, the ... In the metrology of radon, an environmental lung carcinogen, the integrated measurements necessary for epidemiological studies are made very often using the tracks detector LR 115 type 2. For dosimetric analysis, the etched tracks from radon alpha particles on this detector are usually counted by means of an optical microscope or a spark counter. An optimal reading of the track densities which must be converted into radon concentrations, can’t be done without a good mastery of the mode of operation and use of these devices. Furthermore, investigations to know as to whether or not each of those can be used to determine radon concentration are necessary. These are the objectives of the present work in which LR 115 samples exposed to radon for at least 3 months, were chemically developed under standard conditions and read. The track densities obtained with the microscope are very much higher than those of the counter for each sample. These results are consistent with those published by other authors. However, each of these devices can be used interchangeably for alpha tracks counting, as both provide radon concentrations with a very good linear correlation coefficient of 0.95 taking into account their respective calibration factors for the reading of this detector. In addition, the saturation phenomenon for the spark counter reading of LR 115 detector occurs beyond 11,000 tr/cm<sup>2</sup>, a density never reached during our environmental radon measurements. 展开更多
关键词 LR 115 Detector Optical microscope Spark Counter Alpha Track Density Calibration Factor Radon Concentration
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Development of a portable reflectance confocal microscope and its application in the noninvasive in vivo evaluation of mesenchymal stem cell-promoted cutaneous wound healing
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作者 Lixing Zhang Xin Miao +6 位作者 Meijia Wang Aihua Shi Jingwen Wang Zhonglin Ma Yunhai Zhang Jingzhong Zhang Shuang Yu 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2023年第3期268-283,共16页
The process of wound healing is routinely evaluated by histological evaluation in the clinic,which may cause scarring and secondary injury.Reflectance confocal microscopy(RCM)represents a noninvasive,real-time imaging... The process of wound healing is routinely evaluated by histological evaluation in the clinic,which may cause scarring and secondary injury.Reflectance confocal microscopy(RCM)represents a noninvasive,real-time imaging technique that allows in vivo evaluation of the skin.Traditional RCM was wide-probe-based,which limited its application on uneven and covered skin.In this study,we report the development of a portable reflectance confocal microscope(PRCM)in which all components were assembled in a handheld shell.Although the size and weight of the PRCM were reduced based on the use of a microelectromechanical system,the resolution was kept at 0.91μm,and the field of view of the system was 343μm×532μm.When used in vivo,the PRCM was able to visualize cellular and nuclear morphology for both mouse and human skin.PRCM evaluations were then performed on wounds after topically applied mesenchymal stem cells(MSCs)or saline treatment.The PRCM allowed visualization of the formation of collagen bundles,re-epithelization from the wound edge to the wound bed,and hair follicle regeneration,which were consistent with histological evaluations.Therefore,we offer new insights into monitoring the effects of topically applied MSCs on the process of wound healing by using PRCM.This study illustrates that the newly developed PRCM represents a promising device for real-time,noninvasive monitoring of the dynamic process of wound healing,which demonstrates its potential to diagnose,monitor,or predict disease in clinical wound therapy. 展开更多
关键词 Portable reflectance confocal microscope Wound healing Noninvasive optical imaging Real-time in vivo visualization
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Application of a microscopic optical potential of chiral effective field theory in (p, d) transfer reactions
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作者 Yi-Ping Xu Si-Lu Chen Dan-Yang Pang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第1期134-144,共11页
The microscopic global nucleon–nucleus optical model potential(OMP)proposed by Whitehead,Lim,and Holt,the WLH potential(Whitehead et al.,Phys Rev Lett 127:182502,2021),which was constructed in the framework of many-b... The microscopic global nucleon–nucleus optical model potential(OMP)proposed by Whitehead,Lim,and Holt,the WLH potential(Whitehead et al.,Phys Rev Lett 127:182502,2021),which was constructed in the framework of many-body per-turbation theory with state-of-the-art nuclear interactions from chiral effective field theory(EFT),was tested with(p,d)transfer reactions calculated using adiabatic wave approximation.The target nuclei included both stable and unstable nuclei,and the incident energies reached 200 MeV.The results were compared with experimental data and predictions using the phenomenological global optical potential of Koning and Delaroche,the KD02 potential.Overall,we found that the micro-scopic WLH potential described the(p,d)reaction angular distributions similarly to the phenomenological KD02 potential;however,the former was slightly better than the latter for radioactive targets.On average,the obtained spectroscopic factors(SFs)using both microscopic and phenomenological potentials were similar when the incident energies were below approxi-mately 120 MeV.However,their difference tended to increase at higher incident energies,which was particularly apparent for the doubly magic target nucleus 40Ca. 展开更多
关键词 microscopic optical model potential (p d)transfer Spectroscopic factors
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Gold Standard for Skin Cancer Treatment: Surgery (Mohs) or Microscopic Molecular-Cellular Therapy (Curaderm)?
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作者 Bill Elliot Cham 《Journal of Cancer Therapy》 2024年第2期33-47,共15页
Non-melanoma skin cancers or keratinocyte cancers such as basal cell carcinoma and squamous cell carcinoma make up approximately 80% and 20% respectively, of skin cancers with the 6 million people that are treated ann... Non-melanoma skin cancers or keratinocyte cancers such as basal cell carcinoma and squamous cell carcinoma make up approximately 80% and 20% respectively, of skin cancers with the 6 million people that are treated annually in the United States. 1 in 5 Americans and 2 in 3 Australians develop skin cancer by the age of 70 years and in Australia it is the most expensive, amassing $1.5 billion, to treat cancers. Non-melanoma skin cancers are often self-detected and are usually removed by various means in doctors’ surgeries. Mohs micrographic surgery is acclaimed to be the gold standard for the treatment of skin cancer. However, a novel microscopic molecular-cellular non-invasive topical therapy described in this article, challenges the status of Mohs procedure for being the acclaimed gold standard. 展开更多
关键词 Skin Cancer Basal Cell Carcinoma Squamous Cell Carcinoma Mohs Surgery microscopic Molecular-Cellular Curaderm Actinic Keratosis COSMESIS
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Impact Analysis of Microscopic Defect Types on the Macroscopic Crack Propagation in Sintered Silver Nanoparticles
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作者 Zhongqing Zhang Bo Wan +4 位作者 Guicui Fu Yutai Su Zhaoxi Wu Xiangfen Wang Xu Long 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第4期441-458,共18页
Sintered silver nanoparticles(AgNPs)arewidely used in high-power electronics due to their exceptional properties.However,the material reliability is significantly affected by various microscopic defects.In this work,t... Sintered silver nanoparticles(AgNPs)arewidely used in high-power electronics due to their exceptional properties.However,the material reliability is significantly affected by various microscopic defects.In this work,the three primary micro-defect types at potential stress concentrations in sintered AgNPs are identified,categorized,and quantified.Molecular dynamics(MD)simulations are employed to observe the failure evolution of different microscopic defects.The dominant mechanisms responsible for this evolution are dislocation nucleation and dislocation motion.At the same time,this paper clarifies the quantitative relationship between the tensile strain amount and the failure mechanism transitions of the three defect types by defining key strain points.The impact of defect types on the failure process is also discussed.Furthermore,traction-separation curves extracted from microscopic defect evolutions serve as a bridge to connect the macro-scale model.The validity of the crack propagation model is confirmed through tensile tests.Finally,we thoroughly analyze how micro-defect types influence macro-crack propagation and attempt to find supporting evidence from the MD model.Our findings provide a multi-perspective reference for the reliability analysis of sintered AgNPs. 展开更多
关键词 Sintered silver nanoparticles defect types microscopic defect evolution macroscopic crack propagation molecular dynamics simulation cohesive zone model
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Microscopic growth mechanism and edge states of monolayer 1T'-MoTe_(2)
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作者 赵海鹏 刘隐 +7 位作者 杨胜国 林陈昉 陈明星 Kai Braun 罗心仪 李思宇 潘安练 王笑 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期605-611,共7页
Transition metal ditellurides(TMTDs)have versatile physical properties,including non-trivial topology,Weyl semimetal states and unique spin texture.Controlled growth of high-quality and large-scale monolayer TMTDs wit... Transition metal ditellurides(TMTDs)have versatile physical properties,including non-trivial topology,Weyl semimetal states and unique spin texture.Controlled growth of high-quality and large-scale monolayer TMTDs with preferred crystal phases is crucial for their applications.Here,we demonstrate the epitaxial growth of 1T'-MoTe_(2) on Au(111)and graphitized silicon carbide(Gr/SiC)by molecular beam epitaxy(MBE).We investigate the morphology of the grown1T'-MoTe_(2) at the atomic level by scanning tunnelling microscopy(STM)and reveal the corresponding microscopic growth mechanism.It is found that the unique ordered Te structures preferentially deposited on Au(111)regulate the growth of monolayer single crystal 1T'-MoTe_(2),while the Mo clusters were preferentially deposited on the Gr/SiC substrate,which impedes the ordered growth of monolayer MoTe_(2).We confirm that the size of single crystal 1T'-MoTe_(2) grown on Au(111)is nearly two orders of magnitude larger than that on Gr/SiC.By scanning tunnelling spectroscopy(STS),we observe that the STS spectrum of the monolayer 1T'-MoTe_(2) nano-island at the edge is different from that at the interior,which exhibits enhanced conductivity. 展开更多
关键词 transition metal ditellurides 1T'-MoTe_(2) microscopic growth mechanism scanning tunneling microscopy/spectroscopy(STM/S)
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Research Analysis on the Microscopic Properties and Damping Performance of Carbon Nanomaterial-Modified Cement Mortar
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作者 Bin Liu Norhaiza Nordin +2 位作者 Jiyang Wang Jingwei Wu Xiuliang Liu 《Engineering(科研)》 2024年第9期275-283,共9页
The application of carbon nanomaterials, particularly graphene and carbon nanotubes, in cement-based composites is highly significant. These materials demonstrate the multifunctionality of carbon and offer extensive p... The application of carbon nanomaterials, particularly graphene and carbon nanotubes, in cement-based composites is highly significant. These materials demonstrate the multifunctionality of carbon and offer extensive possibilities for technological advancements. This research analyzes how the integration of graphene into cement-based composites enhances damping and mechanical properties, thereby contributing to the safety and durability of structures. Research on carbon nanomaterials is ongoing and is expected to continue driving innovation across various industrial sectors, promoting the sustainable development of building materials. 展开更多
关键词 Carbon Nanomaterials Cement-Based Composites microscopic Properties Damping Properties Modified Cement Mortar
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A review of interaction mechanisms and microscopic simulation methods for CO_(2)-water-rock system
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作者 ZHANG Liehui ZHANG Tao +6 位作者 ZHAO Yulong HU Haoran WEN Shaomu WU Jianfa CAO Cheng WANG Yongchao FAN Yunting 《Petroleum Exploration and Development》 SCIE 2024年第1期223-238,共16页
This work systematically reviews the complex mechanisms of CO_(2)-water-rock interactions,microscopic simulations of reactive transport(dissolution,precipitation and precipitate migration)in porous media,and microscop... This work systematically reviews the complex mechanisms of CO_(2)-water-rock interactions,microscopic simulations of reactive transport(dissolution,precipitation and precipitate migration)in porous media,and microscopic simulations of CO_(2)-water-rock system.The work points out the key issues in current research and provides suggestions for future research.After injection of CO_(2) into underground reservoirs,not only conventional pressure-driven flow and mass transfer processes occur,but also special physicochemical phenomena like dissolution,precipitation,and precipitate migration.The coupling of these processes causes complex changes in permeability and porosity parameters of the porous media.Pore-scale microscopic flow simulations can provide detailed information within the three-dimensional pore and throat space and explicitly observe changes in the fluid-solid interfaces of porous media during reactions.At present,the research has limitations in the decoupling of complex mechanisms,characterization of differential multi-mineral reactions,precipitation generation mechanisms and characterization(crystal nucleation and mineral detachment),simulation methods for precipitation-fluid interaction,and coupling mechanisms of multiple physicochemical processes.In future studies,it is essential to innovate experimental methods to decouple“dissolution-precipitation-precipitate migration”processes,improve the accuracy of experimental testing of minerals geochemical reaction-related parameters,build reliable characterization of various precipitation types,establish precipitation-fluid interaction simulation methods,coordinate the boundary conditions of different physicochemical processes,and,finally,achieve coupled flow simulation of“dissolution-precipitation-precipitate migration”within CO_(2)-water-rock systems. 展开更多
关键词 CO_(2)-water-rock DISSOLUTION precipitation precipitate migration microscopic simulation CO_(2)capture utilization and storage carbon neutrality decouple
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Observation for Leaf Epidermal Characteristics of Four Different Pomegranate Cultivars under Scanning Electron Microscope 被引量:5
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作者 徐迎碧 丁之恩 《Agricultural Science & Technology》 CAS 2008年第3期99-102,共4页
[Objective] The research aimed to provide reference for classification of pomegranate cultivars and studies of genetic relationship among pomegranate cultivars.[Method] The electron microscope scanning was used to com... [Objective] The research aimed to provide reference for classification of pomegranate cultivars and studies of genetic relationship among pomegranate cultivars.[Method] The electron microscope scanning was used to comparatively observe leaf epidermal structures of 4 pomegranate cultivars.[Result] The upper epidermal structures of 4 pomegranate cultivars were similar and showed reticular structure .However, the differences existed in lower epidermis,such as cell shape,cell size and arrangement mode of cell as well as stomatal density,while the structures of leaf vein in lower epidermis of 4 pomegranate cultivars were similar.[Conclusion] The research provided morphological references for studying heterosis of pomegranate to some extent. 展开更多
关键词 POMEGRANATE CULTIVAR LEAF EPIDERMIS Electron microscope scanning
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Solidification process of conventional superalloy by confocal scanning laser microscope 被引量:4
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作者 缪竹骏 单爱党 +3 位作者 王威 卢俊 徐文亮 宋洪伟 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第2期236-242,共7页
The solidification process of a conventional superalloy, IN718, was investigated by confocal scanning laser microscope (CSLM). The liquid fraction during solidification was obtained as a function of real time and te... The solidification process of a conventional superalloy, IN718, was investigated by confocal scanning laser microscope (CSLM). The liquid fraction during solidification was obtained as a function of real time and temperature in reference with the in-situ observation. The characteristics of L→γ transformation were analyzed and the γ growing rate of each stage was also calculated. Scheil equation was employed to predict the segregation behavior, and the predict results are in consistence with the experimental results. As a result, the confocal scanning laser microscope shows a great potential for solidification process research. 展开更多
关键词 IN718 alloy SOLIDIFICATION IN-SITU confocal scanning laser microscope SEGREGATION
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用IM Microscope方法计算无源互调产物
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作者 王海宁 梁建刚 +1 位作者 王积勤 张晨新 《空军工程大学学报(自然科学版)》 CSCD 北大核心 2005年第3期47-49,共3页
在微波与射频无源互调的研究中,预测无源互调产物的电平是非常重要的。在IM Micro-scope方法的基础上进行了改进,在预测过程中直接引入输入信号经过非线性器件后输出信号的幅度和相位变化模型,给出了详细的数学模型,并实例验证了该方法... 在微波与射频无源互调的研究中,预测无源互调产物的电平是非常重要的。在IM Micro-scope方法的基础上进行了改进,在预测过程中直接引入输入信号经过非线性器件后输出信号的幅度和相位变化模型,给出了详细的数学模型,并实例验证了该方法的正确性。 展开更多
关键词 无源互调(PIM) 无源互调产物(PIMP) IM microscope RF
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Obsevation for Epidermal Ultrastructure of Nostoc sphaeroides Kutzing under Scanning Electron Microscope 被引量:1
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作者 李莉 《Agricultural Science & Technology》 CAS 2009年第1期1-3,共3页
[Objective]The experiment aimed to explore a new way for observing surface structure of Nostoc sphaeroides Kutzing. [Method] The scanning electron microscope was used to observe the epidermal ultrastructure of wild an... [Objective]The experiment aimed to explore a new way for observing surface structure of Nostoc sphaeroides Kutzing. [Method] The scanning electron microscope was used to observe the epidermal ultrastructure of wild and cultured Nostoc sphaeroides Kutzing. [ Result] The epidermis of wild and cultured Nostoc sphaeroides Kutzing showed mixture structure of fibril colloid which was reticular arranged. The difference between wild and cultured Nostoc sphaeroides Kutzing was that the outer epidermis of cultured Nostoc sphaeroides Kutzing had trichome distribution but the wild Nostoc sphaeroides Kutzing did not has such distribution. The obsevation results of under smaller than 10 μm by scanning electron microscope was touched thick and showed many folds and distortions. [ Conclusion] The scanning electron microscope was an effective way to study development of Nostoc sphaeroides Kutzing colony and it was worth popularizing. 展开更多
关键词 Nostoc sphaeroides Kutzing Epidermal ultrastructure Scanning electron microscope
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用IM Microscope方法计算无源互调产物
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作者 王海宁 梁建刚 +1 位作者 王积勤 张晨新 《弹箭与制导学报》 CSCD 北大核心 2005年第S4期458-460,共3页
在微波与射频无源互调的研究中,预测无源互调产物的电平是非常重要的,因为这样可以直观的看出无源互调噪声对于器件或者系统的影响。在众多的预测方法中,IM Microscope 方法具有很多优点。文中在IM Microscope 方法的基础上进行了改进,... 在微波与射频无源互调的研究中,预测无源互调产物的电平是非常重要的,因为这样可以直观的看出无源互调噪声对于器件或者系统的影响。在众多的预测方法中,IM Microscope 方法具有很多优点。文中在IM Microscope 方法的基础上进行了改进,在预测过程中直接引入输入信号经过非线性器件后输出信号的幅度和相位变化模型,给出了详细的数学模型,这样可以大大减少很多的测量工作。 展开更多
关键词 无源互调(PIM) 无源互调产物(PIMP) IM microscope RF
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MicroScope高分辨率成像测井技术及应用
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作者 夏竹君 张兰江 +2 位作者 张贺举 杨坚 付琛 《海洋石油》 CAS 2019年第1期54-60,共7页
MicroScope随钻高分辨率成像测井技术是斯伦贝谢公司最新推出,能记录超高分辨率电阻率图像UHRI和多个探测深度深钮电阻率成像图,介绍了超高分辨率电阻率成像图UHRI识别岩性及地层结构、识别沉积构造、划分沉积微相、分析古水流与砂体展... MicroScope随钻高分辨率成像测井技术是斯伦贝谢公司最新推出,能记录超高分辨率电阻率图像UHRI和多个探测深度深钮电阻率成像图,介绍了超高分辨率电阻率成像图UHRI识别岩性及地层结构、识别沉积构造、划分沉积微相、分析古水流与砂体展布等的方法,在南海西部沉积相研究方面发挥了重要作用,是值得推广的新型成像测井技术。 展开更多
关键词 microscope 成像测井 沉积相 测井技术 南海西部
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Observation of Helicotylenchus digonicus by Scanning Electron Microscope
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作者 郑炜 《Plant Diseases and Pests》 CAS 2011年第5期32-33,37,共3页
[ Objective] The paper was to observe Helicotylenchus digonicus by scanning electron microscope (SEM). [ Method ] H. digonicus collected from Changxing of Zhejiang Province was observed under scanning electron micro... [ Objective] The paper was to observe Helicotylenchus digonicus by scanning electron microscope (SEM). [ Method ] H. digonicus collected from Changxing of Zhejiang Province was observed under scanning electron microscope, and its morphological structure was confmned under optical microscope. [ Resuit]The nematode specimens fixed by glutaraldehyde and osmium tetroxide and prepared by critical point drying were unmodified and unshrinkable with clear mor- phological structure, which could be scanned very well by scanning electron microscope. [ Conclusion ] The study provided reference for study and control of H. digonicus. 展开更多
关键词 Helicotylenchus d^gonicus Morphological structure Scanning electron microscope China
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Changes of Calmodulin Distribution in the Embryo Sac of Oryza sativa Before and After Fertilization: an Immunogold Electron Microscope Study 被引量:4
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作者 杨军 赵洁 +1 位作者 梁世平 杨弘远 《Acta Botanica Sinica》 CSCD 2002年第3期264-272,共9页
Changes of calmodulin (CaM) distribution in the embryo sac of rice (Oryza sativa subsp. Japonica) at various stages before and after fertilization have been investigated by using immunogold electron microscopy. Before... Changes of calmodulin (CaM) distribution in the embryo sac of rice (Oryza sativa subsp. Japonica) at various stages before and after fertilization have been investigated by using immunogold electron microscopy. Before pollination, both cytoplasm and vacuoles of the egg cell, synergids and central cell were labeled by gold particles. A small amount of gold particles were localized in the nucleus, endoplasmic reticulum, mitochondria and dictyosomes. From pollination to fertilization, CaM amount increased in these cells, especially rich in the starch of amyloplasts. Increase of gold particles in the central cell began about 2 h earlier than that in the egg cell. There was no distinct difference of CaM amount between the degenerated and the persistent synergids. It is interesting to observe an obvious change of CaM distribution form during pollination and fertilization from scattered single particles to clustered particles, and back again to single particles after the fertilization finished. CaM was also localized extracellularly in the embryo sac wall as well as in the wall and intercellular space of nucellus cells. The extracellular CaM also changes in its amount and form after pollination. These results suggest that CaM, either intra- or extra-cellular, may play important roles in fertilization and zygote formation. 展开更多
关键词 CALMODULIN POLLINATION FERTILIZATION rice embryo sac immunogold electron microscope localization
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A Highly Stable Electrochemical Scanning Tunneling Microscope 被引量:1
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作者 夏志刚 王纪浩 +1 位作者 侯玉斌 陆轻铀 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2015年第1期70-72,I0002,共4页
We demonstrate a home-built electrochemical scanning tunneling microscope (ECSTM). The ECSTM exhibits highly stable performance. The drifting rates in XY and Z directions of the ECSTM are about 67 and 55.6 pm/min, r... We demonstrate a home-built electrochemical scanning tunneling microscope (ECSTM). The ECSTM exhibits highly stable performance. The drifting rates in XY and Z directions of the ECSTM are about 67 and 55.6 pm/min, respectively. Moreover, a specially designed scanner unit successfully solves the well-known problem of large leakage current in high humidity atmosphere. The mechanical structure of the ECSTM is described in detail. The excellent performances of the system are demonstrated by the measured STM images (in copper sulfate solution), including clean and well-ordered large area morphology of Au(111) and the atomically resolved image of highly oriented pyrolytic graphite. 展开更多
关键词 Scanning tunneling microscope ELECTROCHEMISTRY Highly stable
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