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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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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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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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Chalkiness Characters and Scanning Electron Microscope Observation of Rice Grain Endosperm of Japonica Varieties in Southern Henan 被引量:5
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作者 Bo PENG Yanfang SUN +8 位作者 Dongyan KONG Ruihua PANG Xiaohua SONG Huilong LI Jintao LI Qiying ZHOU Qiu HAN Shizhi SONG Hongyu YUAN 《Asian Agricultural Research》 2017年第3期80-85,共6页
Chalkiness characters affect not only the grain appearance,milling,eating and cooking qualities but also the grain nutritional quality in rice,thus it is one of the most important traits in rice. It is very important ... Chalkiness characters affect not only the grain appearance,milling,eating and cooking qualities but also the grain nutritional quality in rice,thus it is one of the most important traits in rice. It is very important for us to investigate the relation of the chalkiness formation and the development of endosperm structure and starch granule of different rice varieties. Here,we have investigated the chalkiness characters such as chalkiness rate,chalkiness degree and chalkiness area in 15 japonica rice varieties from southern Henan. Furthermore,the endosperm structure and starch granules of rice grain were also observed with scanning electron microscope. The results showed that the 15 japonica varieties have a significantly linear relationship between the chalkiness rate and chalkiness degree. Among the varieties,the biggest difference is the chalkiness rate,the second is the chalkiness area,and the last is the chalkiness degree. Moreover,there is a certain correlation between the distribution of starch granules,the arrangement of endosperm cells and the occurrence of grain chalkiness in the different rice varieties. For the same variety,the starch granules of chalky and non-chalky grains have obvious difference,while the starch granules from the transparent part of chalky rice and non-chalky rice do not have significant difference. The results would provide useful references for the improvement of grain quality in rice. 展开更多
关键词 CHALKINESS scanning electron microscope Japonica rice Starch granule ENDOSPERM
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Retrieving analog images from a scanning electron microscopewith a synchronous data acquisition method 被引量:1
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作者 BAI Jiang-hua 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2019年第4期329-334,共6页
In this work,an old scanning electron microscope(SEM)is refurbished to enhance its image processing capability.How to digitally sample and process an analog image is also presented.An NI PCI-6259 multiple input/output... In this work,an old scanning electron microscope(SEM)is refurbished to enhance its image processing capability.How to digitally sample and process an analog image is also presented.An NI PCI-6259 multiple input/output data acquisition(DAQ)board is used to acquire signals originally being sent to an analog display,and then convert the signals into a digital image.Two output channels are used for raster scan of the horizontal and verticle axes of the image buffer,while one input channel is used to read the brightness signals at various coordinate points.Synchronous method is used to maximize the DAQ speed.Finally,the digitally buffered images are read out to display and saved in a hard drive.The hardware and software designs of this work are explained in great detail,which can serve as a very good example for fast synchronous DAQ,advanced virtual instrument design and structural driver programming with LabVIEW. 展开更多
关键词 scanning electron microscope analog image display raster scan synchronous data acquisiotion(DAQ) LABVIEW
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Gill surface architecture of mullet, Mugil soiuy (Basilewsky) : A scanning electron microscope study
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作者 Wang LiangchenDepartment of Biology Nankai University, Tianjin, ChinaGuo ShuhuaTest and Computation Centre Nankai University, Tianjing, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1989年第4期606-609,共4页
Specimens of Mugil soiuy were collected from the coastal waters of Bohai Sea in Tianjin. The gillfilaments were cut with fine scissors and soaked for 24h in a fixative consisting of 2.5% glutaralde-hyde in 0.1 mol lph... Specimens of Mugil soiuy were collected from the coastal waters of Bohai Sea in Tianjin. The gillfilaments were cut with fine scissors and soaked for 24h in a fixative consisting of 2.5% glutaralde-hyde in 0.1 mol lphosporic acid buffer. After three washes in a buffer solution the tissue was fixedin a mixture of 1% osmium tetraoxide at 4℃ for 1h. The tissue was dehydrated in graded ethandethanols and dried. The tissue was examined and photographed with an SEM at an accelerating voltage 展开更多
关键词 A scanning electron microscope study Basilewsky Gill surface architecture of mullet
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Adverse Effects of Permanent Waving and Hair Relaxation—Assessment by Scanning Electron Microscopy (SEM)
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作者 Tokuya Omi Seiji Kawana 《Journal of Cosmetics, Dermatological Sciences and Applications》 2013年第3期45-48,共4页
Permanent waving is very popular in Japan. Polypeptide chains (main chains) form the principal components of hair, and they are lined up longitudinally. Hair relaxation is also called straight permanent waving, and th... Permanent waving is very popular in Japan. Polypeptide chains (main chains) form the principal components of hair, and they are lined up longitudinally. Hair relaxation is also called straight permanent waving, and there are methods that change curly or wavy hair into straight hair. Hair damage as a result of winding, combing, and using high-temperature hairdressing irons is also often seen. By using scanning electron micrographs (SEM) we showed broken hairs and hair damage caused by permanent wave solutions. The hair damage is obvious when comparisons are made with the condition of the hair surface, condition of the cuticle, etc. Hair swelling by permanent wave solutions, manipulations such as winding, etc., inadequate rinsing with water, procedures on injured hair at the outset, etc., are considered possible reasons for any of these types of injury. 展开更多
关键词 PERMANENT Waving HAIR RELAXATION scanNING electron MICROGRAPHS (sem) HAIR Damage
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基于SEM的土体微观结构三维分析与分维计算方法 被引量:1
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作者 张豫川 高旭龙 +1 位作者 刘东发 黄鸿伟 《长江科学院院报》 CSCD 北大核心 2024年第2期91-97,共7页
土体微观结构研究很早就建立了三维空间的分形模型,但分形维数计算所需参数很难由常规土工试验得到,限制了分形理论在土体研究中的应用。基于陕西定边与甘肃兰州原状土样的扫描电镜(SEM)试验,提出了三维化处理与三角形网格原理联合方法... 土体微观结构研究很早就建立了三维空间的分形模型,但分形维数计算所需参数很难由常规土工试验得到,限制了分形理论在土体研究中的应用。基于陕西定边与甘肃兰州原状土样的扫描电镜(SEM)试验,提出了三维化处理与三角形网格原理联合方法,可以得到土体颗粒(孔隙)不同测量尺度对应的表面积与体积计算值,由此实现分形维数的计算,并通过分形理论在土水特征中的应用验证了方法的有效性与可靠性。另外,三维化处理还可获取视孔隙率、比面等土体微观结构参数,可以作为土体微观结构定量分析研究的新途径。 展开更多
关键词 扫描电镜(sem) 微观结构 三维分析 分形维数
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SCANNING ELECTRON MICROSCOPIC STUDY OF FETAL CHICKEN CALVARIAL OSTEOBLAST-LIKE CELLS CULTURED IN VITRO 被引量:1
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作者 柴本甫 汤雪明 +1 位作者 徐荣辉 朱雅萍 《Medical Bulletin of Shanghai Jiaotong University》 CAS 1993年第2期54-59,共6页
Three types of osteoblast-like cells with different cnfigurations could be ob-tained through culturing fetal chicken calvaria in vitro. They were spindle-shaped cells,globular cells, and polygonal or squamous cells. W... Three types of osteoblast-like cells with different cnfigurations could be ob-tained through culturing fetal chicken calvaria in vitro. They were spindle-shaped cells,globular cells, and polygonal or squamous cells. With passage of culture time, there werechanges in configuration so that the spindle-shaped cells and the globular cells turnedgradually into squamous cells, in quantity which increased greatly to produce confluenceand multi-layer formation of cells, and in function as evidenced by emergence ofintracytoplasmic granules, reflecting collagen synthesis. 展开更多
关键词 osteoblast-like cells FETAL CHICKEN CALVARIA in VITRO scanning electron microscope
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小尺寸纳米颗粒的SEM高分辨成像模式探究——以Ni_(2)P为例
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作者 邢宏娜 高文莉 +3 位作者 常帅 冯伟 李兴华 彭勇 《真空科学与技术学报》 CAS CSCD 北大核心 2024年第8期695-703,共9页
相比透射电子显微镜(TEM),扫描电子显微镜(SEM)具有批量进样、成本低、三维成像的优势,但小尺寸纳米颗粒在进行SEM成像时存在容易积碳、分辨率不足、形貌结构信息弱等技术难题。文章以超小空心(34.4 nm)、实心(13.3 nm)Ni_(2)P纳米颗粒... 相比透射电子显微镜(TEM),扫描电子显微镜(SEM)具有批量进样、成本低、三维成像的优势,但小尺寸纳米颗粒在进行SEM成像时存在容易积碳、分辨率不足、形貌结构信息弱等技术难题。文章以超小空心(34.4 nm)、实心(13.3 nm)Ni_(2)P纳米颗粒为例,重点探究了如何通过调控工作模式、工作距离、加速电压、束流等参数获得分辨率高、形貌结构清晰的SEM图像。研究表明,高分辨模式下T2和超高分辨模式下T3探头所成二次电子(SE)像的分辨率明显优于标准模式下ETD探头的,且SE像表面形貌信息多、立体感较好。其中由于T3探头位置最高且仅收集高位二次电子信号,这部分二次电子信号进入透镜的角度准直且能量较低。因此超高分辨模式-T3探头所成SE像分辨率和信噪比最高、形貌衬度良好,但几乎观察不到颗粒内部结构。而高分辨和超高分辨模式下T1(背散射信号)探头所成BSE像成分衬度好,虽景深较小但最有利于观察空心结构。同时探究发现工作距离太小,所得SE像分辨率好但景深差,工作距离太大,SE像分辨率稍弱但景深较好。结合图像质量测量结果,对于文中的Ni_(2)P纳米颗粒,选择适中的工作距离(~8 mm)可获得质量较高的SE像。提升加速电压可有效提高图像分辨率(空心Ni_(2)P在30 kV下可达2.3 nm)。信噪比会随束流的增大而增强,其过大会导致颗粒边缘模糊,选择适中的束流(~0.2 nA)成像效果较好。以上研究结果对小尺寸及中空结构纳米颗粒的SEM成像选择具有一定的借鉴作用。 展开更多
关键词 Ni_(2)P 纳米颗粒 空心结构 扫描电子显微镜 成像参数
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Evolution of pore systems in low-maturity oil shales during thermal upgrading--Quantified by dynamic SEM and machine learning
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作者 Jun Liu Xue Bai Derek Elsworth 《Petroleum Science》 SCIE EI CAS CSCD 2024年第3期1739-1750,共12页
In-situ upgrading by heating is feasible for low-maturity shale oil,where the pore space dynamically evolves.We characterize this response for a heated substrate concurrently imaged by SEM.We systematically follow the... In-situ upgrading by heating is feasible for low-maturity shale oil,where the pore space dynamically evolves.We characterize this response for a heated substrate concurrently imaged by SEM.We systematically follow the evolution of pore quantity,size(length,width and cross-sectional area),orientation,shape(aspect ratio,roundness and solidity)and their anisotropy—interpreted by machine learning.Results indicate that heating generates new pores in both organic matter and inorganic minerals.However,the newly formed pores are smaller than the original pores and thus reduce average lengths and widths of the bedding-parallel pore system.Conversely,the average pore lengths and widths are increased in the bedding-perpendicular direction.Besides,heating increases the cross-sectional area of pores in low-maturity oil shales,where this growth tendency fluctuates at<300℃ but becomes steady at>300℃.In addition,the orientation and shape of the newly-formed heating-induced pores follow the habit of the original pores and follow the initial probability distributions of pore orientation and shape.Herein,limited anisotropy is detected in pore direction and shape,indicating similar modes of evolution both bedding-parallel and bedding-normal.We propose a straightforward but robust model to describe evolution of pore system in low-maturity oil shales during heating. 展开更多
关键词 Low-maturity oil shale Pore elongation Organic matter pyrolysis In-situthermal upgrading scanning electron microscopy(sem) Machine learning
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Scanning Electron Microscopic Observation on Morphologic Characteristics of Sperms in Uremic Patients
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作者 Long-gen XU Shi-fang SHI +6 位作者 Hai-zhen ZHONG Xiao-feng HUANG Xiao-ping QI Qi-zhe SONG Xin-hong WANG Li YAN Zong-fu SHAO 《Journal of Reproduction and Contraception》 CAS 2004年第4期227-232,共6页
To observe the morphologic characteristics of spermatozoon ultramicroscopic structure in uremic subjects.Method Semen sample from lO patients with uremia and 5 healthy men were observed under light microscope and scan... To observe the morphologic characteristics of spermatozoon ultramicroscopic structure in uremic subjects.Method Semen sample from lO patients with uremia and 5 healthy men were observed under light microscope and scanning electronic microscope.Results Abnormalities were found in sperms of uremic patients either in the sperm head (acrosome, acrosomic deficit, nuclear abnormality, pointed head, headless and double head of spermatozoon), neck (rupture, separation and enlargement), or tail (mitochondrial swelling, mitochondrial deficit, tailless, double tail, short tail and curled tail); whereas none of the above-mentioned abnormalities was observed in healthy men. Conclusion Sperms of uremic patients had many morphologic and structural abnormalities in the head, neck and tail. 展开更多
关键词 UREMIA SPERMATOZOON scanning electronic microscope
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Ultrastructural Analysis of the Ontogenetic Development of Shoot Induced from Embryonic Axes of Costa Rican Bean Varieties (<i>Phaseolus vulgaris</i>L.) under <i>in Vitro</i>Conditions by Scanning Electronic Microscopy
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作者 Marisol Jiménez Andrés Gatica +1 位作者 Ethel Sánchez Marta Valdez 《American Journal of Plant Sciences》 2012年第4期489-494,共6页
Common bean (Phaseolus vulgaris L.) is an economic important crop and one of the major grain legumes for human consumption in Latin America, Africa and Asia. A morphological study of shoot induced from embryonic axes ... Common bean (Phaseolus vulgaris L.) is an economic important crop and one of the major grain legumes for human consumption in Latin America, Africa and Asia. A morphological study of shoot induced from embryonic axes development in four Costa Rican bean varieties (Brunca, Huetar, Guaymi and Bribri) cultivated on MS media with or without 5 mg·L–1 de N6-benzylaminopurine (BAP) by scanning electron microscopy (SEM) was developed in the present work. Micrographs showed similarities and differences in the ultrastructure of the apical dome, epidermal surface, stomata and different types of trichomes in the varieties cultivated on organogenesis media. Genotypes with advantageous morphological characteristics for genetic transformation, in particular an exposed apical dome, were identified. This work will contribute to the optimization of the in vitro regeneration of four common bean varieties. 展开更多
关键词 PHASEOLUS vulgaris L BEAN In Vitro ORGANOGENESIS SHOOT scanning electron microscopy (sem)
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Scanning Electron Microscopically Study of Sesame Seeds Infected with Macrophomina phaseolina
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作者 D. A. El-Wakil A. M. Mahdy R. Z. El-Menshawy 《Journal of Agricultural Science and Technology(A)》 2011年第1X期96-99,共4页
The direct impact of seed-borne fungi on seed is considerable. Many fungi are serious parasites of seed primordial and maturing seeds and reduce yield of seed both quantitatively and qualitatively. Other fungi, includ... The direct impact of seed-borne fungi on seed is considerable. Many fungi are serious parasites of seed primordial and maturing seeds and reduce yield of seed both quantitatively and qualitatively. Other fungi, including saprophytes and very weak parasites, may lower the quality of seeds by causing discoloration which may seriously depreciate the commercial value of seeds, particularly of grain when graded for consumption. Studies by using scanning electron microscopy (SEM) confirmed the importance of the seed coat, and seed cells as infection sites as well as location of the mycelium of the investigated fungus. Macrophominaphaseolina The present investigation is undertaken to study the colonization, infection and fungal establishment on different sesame seed parts by (SEM). A successful colonization of M. phaseolina to seed tissues was also detected. Different forms of pycnidial shapes were also observed. 展开更多
关键词 scanning electron microscope Macrophomina phaseolina sesame seed
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COEXISTENCE OF OSTEOARTHRITIS AND OSTEOPOROSIS IN FEMORAL HEAD: A SCANNING ELECTRON MICROSCOPIC STUDY
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作者 柴本甫 汤雪明 李慧 《Medical Bulletin of Shanghai Jiaotong University》 CAS 2000年第2期71-76,共6页
Objective To ascertain the coexistence of osteoarthritis and osteoporosis in the femoral head. Methods During total hip replacement for osteoarthritis of hip joint in 12 female patients with an average age of 56 years... Objective To ascertain the coexistence of osteoarthritis and osteoporosis in the femoral head. Methods During total hip replacement for osteoarthritis of hip joint in 12 female patients with an average age of 56 years, the femoral heads were procured. After processing the femoral had, specimens were studied under scanning electron microscope. Results Different degrees of osteoarthritic lesions (characterized by degeneration of articular cartilage and hyperplasia of subchondral bone tissues) could coexust with osteoporotic lesions (characterized by icicle-like trabeculae ) in the femoral had. The hyperplas- tic bone tissues of osteoarthritis lay in the vicinity of icicle-like trabeculae. However, they did not care into contact, nor did they exert influence on each other. Coexistence of these two different lesions covered a brood territory extending from the deep surface of subchondral bone plate to the head-neck junction of femoral head. Conclusion The results suggest that osteoarthritis and osteoporosis do coexist in the femoral head. 展开更多
关键词 osteoarthritis osteoporosis coexistence scanning electron microscope
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致密砂岩碳酸盐矿物SEM-CL和EPMA矿物学表征及其成岩意义——以川西坳陷须家河组为例
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作者 余瑜 林良彪 +3 位作者 李真 孟万斌 童馗 梁庆韶 《沉积学报》 CAS CSCD 北大核心 2023年第5期1468-1477,共10页
扫描电镜—阴极发光(SEM-CL)可通过同时分析矿物的微观结构和阴极发光特性来反映成岩机制及流体来源,但碳酸盐矿物在SEM-CL下的发光特性及其影响因素尚不明确。应用光学显微镜阴极发光(OM-CL)、电子探针(EPMA)和SEM-CL等技术手段,以川... 扫描电镜—阴极发光(SEM-CL)可通过同时分析矿物的微观结构和阴极发光特性来反映成岩机制及流体来源,但碳酸盐矿物在SEM-CL下的发光特性及其影响因素尚不明确。应用光学显微镜阴极发光(OM-CL)、电子探针(EPMA)和SEM-CL等技术手段,以川西坳陷须家河组致密砂岩中碳酸盐矿物为研究对象,分析碳酸盐矿物在OM-CL和SEM-CL下发光特性的差异,评估影响碳酸盐矿物SEM-CL发光特性的因素,探讨砂岩中方解石胶结物的成岩意义。结果表明,相比OM-CL,SEM-CL在区分碳酸盐岩屑和碳酸盐胶结物方面具有更高的灵敏度。当Mn/Fe值低于0.1或Mn/Fe值介于0.1~0.5且Fe含量低于0.1%时,碳酸盐矿物具有中低强度的SEM-CL发光强度;当Mn/Fe值高于0.5且Fe含量高于0.1%时,碳酸盐矿物在SEM-CL照射下几乎不发光。Mn/Fe值和Fe含量是影响SEM-CL照射下碳酸盐矿物发光强度的主要因素。阴极发光分析和EPMA元素组成面扫描分析表明,方解石胶结物的元素分布是均质的,形成于同一成岩世代,晚于长石等矿物的溶解。岩屑砂岩和岩屑石英砂岩的方解石胶结物具有相同的来源,表现为高Mn/Fe特征;钙屑砂岩的方解石胶结物具低Mn高Fe特征,成分组成与白云石岩屑相似,推测流体可能受到白云石岩屑溶解的影响。 展开更多
关键词 方解石胶结物 扫描电镜—阴极发光 成岩作用 致密砂岩 须家河组 四川盆地
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Bacteriological and electron microscopic examination of primary intrahepatic stones 被引量:17
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作者 Shuo-Dong Wu, Hong Yu and Ji-Mei Sun Department of General Surgery Department of Microbiology Center Second Affiliated Hos- pital China Medical University, Shenyang 110004, China 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2006年第2期228-231,共4页
BACKGROUND: Primary intrahepatic cholelithiasis is usually combined with biliary tract infection. This research was undertaken to investigate the relationship between intrahepatic stones and biliary tract infection. M... BACKGROUND: Primary intrahepatic cholelithiasis is usually combined with biliary tract infection. This research was undertaken to investigate the relationship between intrahepatic stones and biliary tract infection. METHODS: Thirty-five bile samples and 30 stones specimens were cultured for bacteria and 12 stones specimens were examined with a scan electron microscope (SEM) or a transmission electron microscope (TEM). RESULT: 94.2% bile samples and 96.7% stones specimens were positive in bacteria culture. Bacteria were found in stones under SEM and TEM. CONCLUSION: Bacteria in stones are associated with the infection of the biliary tract. 展开更多
关键词 CHOLELITHIASIS BACTERIA scan electron microscope transmission electron microscope BIOFILM
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Surface characteristics analysis of fractures induced by supercritical CO_(2)and water through three-dimensional scanning and scanning electron micrography 被引量:7
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作者 Hao Chen Yi Hu +4 位作者 Jiawei Liu Feng Liu Zheng Liu Yong Kang Xiaochuan Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2021年第5期1047-1058,共12页
Morphology of hydraulic fracture surface has significant effects on oil and gas flow,proppant migration and fracture closure,which plays an important role in oil and gas fracturing stimulation.In this paper,we analyze... Morphology of hydraulic fracture surface has significant effects on oil and gas flow,proppant migration and fracture closure,which plays an important role in oil and gas fracturing stimulation.In this paper,we analyzed the fracture surface characteristics induced by supercritical carbon dioxide(SC-CO_(2))and water in open-hole and perforation completion conditions under triaxial stresses.A simple calculation method was proposed to quantitatively analyze the fracture surface area and roughness in macro-level based on three-dimensional(3D)scanning data.In micro-level,scanning electron micrograph(SEM)was used to analyze the features of fracture surface.The results showed that the surface area of the induced fracture increases with perforation angle for both SC-CO_(2)and water fracturing,and the surface area of SC-CO_(2)-induced fracture is 6.49%e58.57%larger than that of water-induced fracture.The fractal dimension and surface roughness of water-induced fractures increase with the increase in perforation angle,while those of SC-CO_(2)-induced fractures decrease with the increasing perforation angle.A considerable number of microcracks and particle peeling pits can be observed on SC-CO_(2)-induced fracture surface while there are more flat particle surfaces in water-induced fracture surface through SEM images,indicating that fractures tend to propagate along the boundary of the particle for SC-CO_(2)fracturing while water-induced fractures prefer to cut through particles.These findings are of great significance for analyzing fracture mechanism and evaluating fracturing stimulation performance. 展开更多
关键词 Supercritical carbon dioxide(SC-CO_(2))fracturing Quantitative characterization of surface features Surface roughness and fractal dimension Three-dimensional(3D)scanning scanning electron micrograph(sem)
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Mssbauer and electron microscopy study of martensitic transformations in an Fe-Mn-Mo alloy
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作者 T.Kirindi U.Sari M.Kurt 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2010年第4期448-452,共5页
The kinetic,morphological,crystallographic,and magnetic characteristics of thermally induced martensites in Fe-13.4wt% Mn-5.2wt%Mo alloy were investigated by scanning electron microscopy(SEM),transmission electron m... The kinetic,morphological,crystallographic,and magnetic characteristics of thermally induced martensites in Fe-13.4wt% Mn-5.2wt%Mo alloy were investigated by scanning electron microscopy(SEM),transmission electron microscopy(TEM),and M(o|¨)ssbauer spectroscopy.The experimental results reveal that two types of thermal-induced martensites,e(hcp) andα'(bcc) martensites,are formed in the as-quenched condition,and these transformations have athermal characters.Mo addition to the Fe-Mn alloy does not change the coexistence ofεandα' martensites with the Mn content between 10wt%and 15wt%.Besides,M(o|¨)ssbauer spectra reveal a paramagnetic character with a singlet for theγ(fcc) austenite andεmartensite phases and a ferromagnetic character with a broad sextet for theα' martensite phase. The volume fraction ofα' martensite forming in the quenched alloy is much more than that of theεmartensite. 展开更多
关键词 Fe-Mn alloy MOLYBDENUM martensitic transformation scanning electron microscopy(sem transmission electron microscopy(TEM) Mossbauer spectroscopy
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Electronic Scanning of Uterine Endometrium in Postpartum Cow
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作者 TIANWen-ru HEJian-bin 《Journal of Northeast Agricultural University(English Edition)》 CAS 2000年第2期118-124,共7页
Two postpartum cows were used to study the ultrastructural changes of uterine endometrium by using scanning electron microscope.The results showed that the process of repair of uterine endometrium after calving was de... Two postpartum cows were used to study the ultrastructural changes of uterine endometrium by using scanning electron microscope.The results showed that the process of repair of uterine endometrium after calving was demonstrated by scanning electron microscope through a series of endometrium biopsy.Some part of the endometrium was damaged after calving and its adjacent endometrium cells became necrosis and exfoliated during the first 7 days post-partum;the cilium and microvillus of the epithelial cell in the undamaged area of the endometrium disappeared.By 26 days postpartum the damaged area reduced and the cilium and microvillus increased in their numbers.The damaged tissues were all repaired by day 60 postpartum. 展开更多
关键词 postpartum cow uterine involution scanning electron microscope
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