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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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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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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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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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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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Visualization of Methamphetamine-Contaminated Fingermarks on Glass Surfaces by Field Emission Scanning Electron Microscope for Forensic Investigation
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作者 Sarah Aliah Amir Sarifudin Kah Haw Chang +1 位作者 Bee Ee Khoo Ahmad Fahmi Lim Abdullah 《Journal of Forensic Science and Medicine》 2023年第1期6-11,共6页
Background:Fingermark is an individual’s primary identification source.It is helpful in determining individuals involved in illegal activities and is frequently encountered in clandestine laboratories.During forensic... Background:Fingermark is an individual’s primary identification source.It is helpful in determining individuals involved in illegal activities and is frequently encountered in clandestine laboratories.During forensic investigation,the critical question to be answered is whether a fingermark was left on a surface before or after the initiation of an unlawful activity.Aims and Objectives:This study aimed to investigate the visualization of methamphetamine-contaminated fingermarks on glass surfaces and estimate the immediacy of their depositions.Materials and Methods:In this study,the prior-deposition contaminated fingermarks,i.e.,fingermarks deposited a surface priorly contaminated by methamphetamine,and the postdeposition contaminated fingermarks,i.e.,fingermarks deposited on a clean surface but subsequently contaminated with methamphetamine were visualized and compared using Field Emission Scanning Electron Microscope(FESEM).Results:Under FESEM,the latent fingermarks and the crystalline structure of methamphetamine were clearly visualized.The postdeposition contaminated fingermarks appeared in smudge conditions in all the three replicate samples,where the ridge and nonridge areas could not be well-distinguished.On the contrary,the prior-deposition contaminated fingermark demonstrated distinct separations between ridges and nonridges.However,the application of fingerprint powders reduced the possibility to determine the immediacy of deposition.Conclusion:To conclude,both prior-deposition contaminated fingermarks and postdeposition contaminated fingermarks can be discriminated,providing information on the instance when a fingermark was left on a surface. 展开更多
关键词 FINGERMARK METHAMPHETAMINE scanning electron microscope VISUALIZATION POWDER
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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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Nanoparticles Production and Inclusion in <i>S. aureus</i>Incubated with Polyurethane: An Electron Microscopy Analysis
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作者 Lyubov V. Didenko George A. Avtandilov +7 位作者 Natalia V. Shevlyagina N. M. Shustrova Tatiana A. Smirnova I. Y. Lebedenko Roberta Curia Claudio Savoia Francesco Tatti Marziale Milani 《Open Journal of Medical Imaging》 2013年第2期69-73,共5页
This study shows that submicron/nanoparticles found in bacterial cells (S. aureus) incubated with polyurethane (a material commonly used for prostheses in odontostomatology) are a consequence of biodestruction. The pr... This study shows that submicron/nanoparticles found in bacterial cells (S. aureus) incubated with polyurethane (a material commonly used for prostheses in odontostomatology) are a consequence of biodestruction. The presence of polyurethane nanoparticles into bacterial vesicles suggests that the internalization process occurs through endocytosis. TEM and FIB/SEM are a suitable set of correlated instruments and techniques for this multi facet investigation: polyurethane particles influence the properties of S. aureus from the morpho-functional standpoint that may have undesirable effects on the human body. S. aureus and C. albicans are symbiotic microorganisms;it was observed that C. albicans has a similar interaction with polyurethane and an increment of the biodestruction capacity is expected by its mutual work with S. aureus. 展开更多
关键词 POLYURETHANE S. AUREUS Biodestruction Endocytosis FIB/SEM (Focused Ion Beam/scanning electron microscope) TEM (Transmission electron microscope) STEM (scanning Transmission electron microscope)
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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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成熟麝香、白香及麝鼠香的扫描电镜观察研究
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作者 竭航 赵贵军 +3 位作者 曾德军 封孝兰 张承露 郑程莉 《西南大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第9期105-111,共7页
通过光学显微镜观察与电镜扫描对比分析成熟麝香、白香和麝鼠香3种样品之间的差异,并对林麝香囊皮肤进行了观测,旨在探究麝香的生理分泌机理.结果表明:成熟麝香主要由10~200μm不规则云状团块组成,在团块上附着或者周围散布着较为模糊... 通过光学显微镜观察与电镜扫描对比分析成熟麝香、白香和麝鼠香3种样品之间的差异,并对林麝香囊皮肤进行了观测,旨在探究麝香的生理分泌机理.结果表明:成熟麝香主要由10~200μm不规则云状团块组成,在团块上附着或者周围散布着较为模糊的星云状物质.白香的均一性较好,光镜下显示为高密度星云状,电镜下呈现为葡萄状样颗粒簇,单一颗粒直径约为0.2μm,夹杂少许椭球形细胞结构和干酪样不规则团块.麝鼠香视野在电镜下较为模糊,但也呈现为葡萄状样颗粒簇,单一颗粒大小为0.5~2μm.林麝香囊颈部皮肤存在多个约2 mm^(2)的排泄小孔,直径约100μm.香囊内壁皮肤也观测到少许20~100μm的排泄小孔. 展开更多
关键词 麝香 白香 麝鼠香 扫描电镜
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新疆15种猪毛菜属植物花粉扫描电镜图像数据集
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作者 李全胜 王晓丽 +2 位作者 刘婷婷 胡林 曹姗姗 《中国科学数据(中英文网络版)》 CSCD 2024年第2期202-208,共7页
本研究对2007年盛花末期在新疆北部地区采集的粗枝猪毛菜(Salsola subcrassa)、东方猪毛菜(S. orientalis)、短柱猪毛菜(S. lanata)等15种猪毛菜进行花果对照鉴定分类,然后用LEO-1430VP型扫描电子显微镜对这些花粉进行多角度拍摄、观察... 本研究对2007年盛花末期在新疆北部地区采集的粗枝猪毛菜(Salsola subcrassa)、东方猪毛菜(S. orientalis)、短柱猪毛菜(S. lanata)等15种猪毛菜进行花果对照鉴定分类,然后用LEO-1430VP型扫描电子显微镜对这些花粉进行多角度拍摄、观察分析,最大放大倍率20000倍,图像分辨率达1023×766像素,共收录84张图像。数据集中的猪毛菜由藜科植物分类学专家二次鉴定,并由专业人员操作扫描电镜观察花粉性状。读者可以根据猪毛菜种名在本数据集中查阅相应的花粉扫描电镜图像。本数据集的发布,为深入研究新疆乃至中亚地区猪毛菜属植物花粉的典型特征提供了便利,进一步补充和完善了根据猪毛菜属植物的形态特征建立的分组系统,为猪毛菜属植物类群的孢粉学、分类学、生态学等方面的研究提供重要参考。 展开更多
关键词 猪毛菜属 花粉 扫描电镜 孢粉学
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中国南方高成熟泥页岩有机质微观特征研究
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作者 焦淑静 梁萍萍 +1 位作者 郭伟 周晓峰 《电子显微学报》 CAS CSCD 北大核心 2024年第3期317-323,共7页
页岩有机质孔隙对页岩气勘探开发有着重要的指示作用,对页岩气生成及运移机理的认知有着重要意义,是研究人员关注的焦点问题。本文采用自然断面制样方法,利用扫描电镜对中国南方高成熟泥页岩进行观察研究发现,有机质主要以三种形态存在... 页岩有机质孔隙对页岩气勘探开发有着重要的指示作用,对页岩气生成及运移机理的认知有着重要意义,是研究人员关注的焦点问题。本文采用自然断面制样方法,利用扫描电镜对中国南方高成熟泥页岩进行观察研究发现,有机质主要以三种形态存在于页岩中,一种是细微的颗粒状,微粒尺寸约10~100 nm,与周围矿物界限不明显;一种是呈块状,尺寸多超过10μm,断口表面光滑;一种是部分保留生物形态的有机质,从数量而言以前两种为主。结合有机质成因及特征,作者对其进行分类:第一种为干酪根,第二种为沥青,第三种为生物碎屑。干酪根和沥青中都可能生成孔隙,干酪根内孔隙尺寸较小,形态不规则,沥青中的孔隙尺寸较大,呈气泡状,孔壁较圆滑。因为在泥页岩中干酪根占比比固体沥青多,而且高成熟度的页岩中干酪根中普遍发育孔隙,沥青中较少发育孔隙,所以干酪根孔隙是有机质孔隙的主体。 展开更多
关键词 高成熟 页岩 有机质孔隙 有机质类型 干酪根 沥青 扫描电镜
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高温环境下花岗岩损伤演变及量化研究
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作者 李琴 张峰 +2 位作者 翟预立 黄志强 陈科 《地下空间与工程学报》 CSCD 北大核心 2024年第2期437-448,459,共13页
为揭示高温环境下岩石的损伤演变,将花岗岩加热至600℃、800℃、1 000℃并分析其断口形貌特征,采用数字图像处理技术、损伤力学和“损伤微元”理论,结合各温度下花岗岩细观裂纹特性,建立了岩石损伤评价方法,并开展岩石损伤量化研究。结... 为揭示高温环境下岩石的损伤演变,将花岗岩加热至600℃、800℃、1 000℃并分析其断口形貌特征,采用数字图像处理技术、损伤力学和“损伤微元”理论,结合各温度下花岗岩细观裂纹特性,建立了岩石损伤评价方法,并开展岩石损伤量化研究。结果表明:花岗岩的断口特征与裂纹的萌生和扩展相关,且裂纹数量、分布密度随温度上升而增加;各温度区间下,花岗岩细观裂纹长度服从对数正态分布,内部损伤表现形式以短裂纹为主,长裂纹为辅;不同温度下花岗岩细观裂纹由单方向延伸发育成多方向贯穿,最高损伤度和温度呈正相关。该研究揭示了高温下花岗岩内部裂纹损伤演化规律,该损伤评价方法对高温地层岩石稳定性评估和地下工程的维护具有重要的参考价值。 展开更多
关键词 岩石裂纹 细观形貌 扫描电镜 能谱仪 损伤评价
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膨胀土微结构对膨胀行为的影响
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作者 刘正楠 张锐 +2 位作者 唐德力 刘昭京 周豫 《土木与环境工程学报(中英文)》 CSCD 北大核心 2024年第2期60-69,共10页
评估膨胀土的膨胀行为对于膨胀土地区的结构设计十分重要。因降雨入渗,膨胀土在垂直方向和水平方向均产生膨胀变形,当膨胀变形受抑制时将产生膨胀压力,影响其周围结构的稳定性。为揭示膨胀土在增湿膨胀过程中出现各向异性的原因,从微观... 评估膨胀土的膨胀行为对于膨胀土地区的结构设计十分重要。因降雨入渗,膨胀土在垂直方向和水平方向均产生膨胀变形,当膨胀变形受抑制时将产生膨胀压力,影响其周围结构的稳定性。为揭示膨胀土在增湿膨胀过程中出现各向异性的原因,从微观角度出发,通过电镜扫描(SEM)对百色中膨胀土和枝江弱膨胀土的微观结构进行观察,并通过图像处理技术统计分析膨胀土内黏土矿物颗粒的层状排列。通过研发的二维膨胀仪和改进的试件制备方法,从宏观角度测得了侧限条件下的两向膨胀规律。研究结果表明,膨胀土的微观结构呈片状且面-面相叠;当膨胀土处于天然松散状态时,其内部的黏土矿物颗粒随机定向排列且集聚;压实后,因受各向不均等应力作用,黏土矿物颗粒开始趋向于水平层状排列;干密度越大,土样越密实,其水平层状排列越显著。侧限条件下,两向的膨胀规律表现出显著的差异,干密度越大,膨胀性越强,这种差异就越明显。然而,对黏土矿物颗粒来说,其膨胀的方向垂直于其长轴,高度的水平定向是造成膨胀土在宏观上表现出膨胀各向异性的原因,这种两向的膨胀差异受到干密度和膨胀性的影响,难以做出预测,建议在工程实践中实测两向的膨胀规律。 展开更多
关键词 膨胀土 膨胀各向异性 微观结构 电镜扫描 膨胀试验
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