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Soft X ray Diagnosis on Seed Development and Observation on Seed Germination and Seedling Growth in Artificial Hybridization in Cunninghamia and Cryptomeria 被引量:1
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作者 李文钿 奇文清 +1 位作者 成小飞 胡适宜 《Acta Botanica Sinica》 CSCD 1999年第7期690-694,共5页
An intergeneric artificial hybridization was conducted between Cunninghamia R. Br. and Cryptomeria D.Don The results are as follows:1. A considerable number of hybrid seeds shed from 76 pollinated cones were ... An intergeneric artificial hybridization was conducted between Cunninghamia R. Br. and Cryptomeria D.Don The results are as follows:1. A considerable number of hybrid seeds shed from 76 pollinated cones were empty and a total of 628 looks plump. Soft X ray radiographs showed that, still and all, a majority of the “plump" seeds were embryoless (597, 95.6%) whereas some were partially developed (17,2.7%) and only a few were really full (14, 2.2%). 2. Germination test showed that all of the radiographed hybrid seeds with fully developed embryos were germinable whereas those with partially developed embryos were ungerminable. 3. Physiologically, the growth rate of hypocotyl, the date for shedding of seed coat and spreading of cotyledons, the elongation of epicotyl, and the branching of shoot of the 11 month old seedlings showed a tendency to fall behind those of the female parent; morphologically, the 11 month old hybrid seedlings with linear leaves appeared rather short, slender and weak, whereas the seedlings of the female parents with linear_lanceolate leaves appeared rather tall, stout and strong. 4. It is considered that the hybrid may be true and the crossability reveals a close phylogenetic affinity of Cunninghamia with Cryptomeria. 展开更多
关键词 Cunninghamia CRYPTOMERIA Artificial hybridization Soft x ray
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INTERFACIAL BONDING IN AS DEPOSITED AND ANNEALED Co/C SOFT X RAY MULTILAYER MIRRORS
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作者 白海力 姜恩永 +1 位作者 王存达 田仁玉 《Transactions of Tianjin University》 EI CAS 1998年第2期80-85,共6页
Interfacial bonding in as deposited and annealed Co/C soft X ray multilayer structures is investigated by X ray photo electron spectroscopy (XPS).It is found that there is interdiffusion between cobalt and carbon ... Interfacial bonding in as deposited and annealed Co/C soft X ray multilayer structures is investigated by X ray photo electron spectroscopy (XPS).It is found that there is interdiffusion between cobalt and carbon in the as deposited Co/C multilayers,and this is confirmed by structure characterization using low angle X ray diffraction (LAXD).The calculation of the chemical shifts in Co C system based on Miedemas macroscopic atom model suggests that it is impossible to detect the chemical shift experimentally in the Co C compound,which is consistent with the XPS results.The presence of metallic carbide bonding is evidenced through the nature of the carbon bonding in survey taken at Co C and C Co interfaces of annealed samples.Our results also indicate that XPS is a direct method to probe the chemical bonding at the interfaces. 展开更多
关键词 soft x ray MULTILAYERS interfacial bonding thermodynamic properties
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Fast X-ray imaging beamline at SSRF
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作者 Ke Li Hong-Lan Xie +5 位作者 Ya-Nan Fu Fei-Xiang Wang Guo-Hao Du Jian-Feng ji Biao Deng Ti-Qiao Xiao 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第9期68-81,共14页
The fast X-ray imaging beamline(BL16U2)at Shanghai Synchrotron Radiation Facility(SSRF)is a new beamline that provides X-ray micro-imaging capabilities across a wide range of time scales,spanning from 100 ps toμs and... The fast X-ray imaging beamline(BL16U2)at Shanghai Synchrotron Radiation Facility(SSRF)is a new beamline that provides X-ray micro-imaging capabilities across a wide range of time scales,spanning from 100 ps toμs and ms.This beamline has been specifically designed to facilitate the investigation of a wide range of rapid phenomena,such as the deformation and failure of materials subjected to intense dynamic loads.In addition,it enables the study of high-pressure and high-speed fuel spray processes in automotive engines.The light source of this beamline is a cryogenic permanent magnet undulator(CPMU)that is cooled by liquid nitrogen.This CPMU can generate X-ray photons within an energy range of 8.7-30 keV.The beamline offers two modes of operation:monochromatic beam mode with a liquid nitrogen-cooled double-crystal monochromator(DCM)and pink beam mode with the first crystal of the DCM out of the beam path.Four X-ray imaging methods were implemented in BL16U2:single-pulse ultrafast X-ray imaging,microsecond-resolved X-ray dynamic imaging,millisecond-resolved X-ray dynamic micro-CT,and high-resolution quantitative micro-CT.Furthermore,BL16U2 is equipped with various in situ impact loading systems,such as a split Hopkinson bar system,light gas gun,and fuel spray chamber.Following the completion of the final commissioning in 2021 and subsequent trial operations in 2022,the beamline has been officially available to users from 2023. 展开更多
关键词 Multiple time-scale x ray imaging Single-pulse x ray imaging Dynamic 2D imaging Dynamic micro-CT
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Comparison of efficacy of lung ultrasound and chest X-ray in diagnosing pulmonary edema and pleural effusion in ICU patients: A single centre, prospective, observational study
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作者 Kunal Tewari Sumanth Pelluru +5 位作者 Deepak Mishra Nitin Pahuja Akash Ray Mohapatra Jyotsna Sharma Om Bahadur Thapa Manjot Multani 《Open Journal of Anesthesiology》 2024年第3期41-50,共10页
Background and Aims While chest X-ray (CXR) has been a conventional tool in intensive care units (ICUs) to identify lung pathologies, computed tomography (CT) scan remains the gold standard. Use of lung ultrasound (LU... Background and Aims While chest X-ray (CXR) has been a conventional tool in intensive care units (ICUs) to identify lung pathologies, computed tomography (CT) scan remains the gold standard. Use of lung ultrasound (LUS) in resource-rich ICUs is still under investigation. The present study compares the utility of LUS to that of CXR in identifying pulmonary edema and pleural effusion in ICU patients. In addition, consolidation and pneumothorax were analyzed as secondary outcome measures. Material and Methods This is a prospective, single centric, observational study. Patients admitted in ICU were examined for lung pathologies, using LUS by a trained intensivist;and CXR done within 4 hours of each other. The final diagnosis was ascertained by an independent senior radiologist, based on the complete medical chart including clinical findings and the results of thoracic CT, if available. The results were compared and analyzed. Results Sensitivity, specificity and diagnostic accuracy of LUS was 95%, 94.4%, 94.67% for pleural effusion;and 98.33%, 97.78%, 98.00% for pulmonary edema respectively. Corresponding values with CXR were 48.33%, 76.67%, 65.33% for pleural effusion;and 36.67%, 82.22% and 64.00% for pulmonary edema respectively. Sensitivity, specificity and diagnostic accuracy of LUS was 91.30%, 96.85%, 96.00% for consolidation;and 100.00%, 79.02%, 80.00% for pneumothorax respectively. Corresponding values with CXR were 60.87%, 81.10%, 78.00% for consolidation;and 71.3%, 97.20%, 96.00% for pneumothorax respectively. Conclusion LUS has better diagnostic accuracy in diagnosis of pleural effusion and pulmonary edema when compared with CXR and is thus recommended as an effective alternative for diagnosis of these conditions in acute care settings. Our study recommends that a thoracic CT scan can be avoided in most of such cases. 展开更多
关键词 Chest x ray (CxR) CONSOLIDATION Pulmonary edema Pleural effusion Lung ultrasound (LUS) PNEUMOTHORAx
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A Straightforward Method of Calculating Finely the Soft X-Ray Spectra of Hydrogenlike Highly Ionized-States
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作者 尹钊 张国营 张学龙 《Journal of Southeast University(English Edition)》 EI CAS 2001年第2期87-90,共4页
A new method of calculating finely the soft X ray spectra of hydrogenlike highly ionized states is presented. It is based on the relation of the ionicity and the ionization energies of hydrogenlike atoms and the new... A new method of calculating finely the soft X ray spectra of hydrogenlike highly ionized states is presented. It is based on the relation of the ionicity and the ionization energies of hydrogenlike atoms and the new model of potential function of hydrogenlike atoms. The relativistic revision and the spin orbit couping of excitation energy levels are taken into account. The calculated results are in good agreement with the experiments. 展开更多
关键词 hydrogenlike ions spectra of soft x ray effect of ionicity relativistic effect
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上海光源储存环X-ray针孔相机系统设计 被引量:5
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作者 黄国庆 陈杰 +2 位作者 陈之初 冷用斌 叶恺容 《核技术》 CAS CSCD 北大核心 2010年第11期806-809,共4页
上海光源(SSRF)储存环X-ray针孔相机系统主要由X-ray引出前端、衰减片、小孔、靶片、相机、PXI控制器及图像采集等构成,数据采集处理软件在LabVIEW平台上开发,与控制系统的接口通过EPICS Shared Memory IOCcore技术实现。2009年8月开始... 上海光源(SSRF)储存环X-ray针孔相机系统主要由X-ray引出前端、衰减片、小孔、靶片、相机、PXI控制器及图像采集等构成,数据采集处理软件在LabVIEW平台上开发,与控制系统的接口通过EPICS Shared Memory IOCcore技术实现。2009年8月开始的长时间在线运行证明引出前端是安全的,在300mA运行时,测量引出窗的最高温度≤36℃。该系统设计合理、性能稳定,可在线实时测量数十μm束团横向截面尺寸,从而实现3.9nm·rad发射度的测量。 展开更多
关键词 上海光源 xray针孔相机 EPICS 发射度
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Study of NdCl_3-FeCl_3-Graphite Intercalation Compounds by X-Ray Photoelectron Spectroscopy 被引量:1
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作者 侯仰龙 韦永德 《Journal of Rare Earths》 SCIE EI CAS CSCD 2001年第1期18-20,共3页
NdCl 3 FeCl 3 graphite intercalation compounds were synthesized by molten salt exchange method. The state of the intercalates and the relative contents of Nd, Fe, Cl, C in the product were determined by X ray ph... NdCl 3 FeCl 3 graphite intercalation compounds were synthesized by molten salt exchange method. The state of the intercalates and the relative contents of Nd, Fe, Cl, C in the product were determined by X ray photoelectron spectroscopy(XPS). From the XPS data, it is concluded that the binding energy of Fe2p electrons is about 711 20~710 3 eV, the binding energy of Nd3d electrons is about 983 08~983 20 eV, and Fe in the product has two valence states (Fe 3+ and Fe 2+ ). 展开更多
关键词 rare earths neodymium chloride graphite intercalation compounds x ray photoelectron spectroscopy
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联合应用近红外线、高频超声、钼靶x—ray对乳腺癌的早期诊断分析 被引量:3
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作者 张明明 陈艾江 《中国中医药咨讯》 2011年第10期107-107,共1页
目的:比较应用近红外线、高频超声、钼靶x—ray各自对乳腺癌早期诊断的价值,探讨联合应用近红外线、高频超声、钼靶x—ray对乳腺癌早期诊断的价值。方法:对81例经近红外线扫描、经B超检查、钼钯X线检查的病例进行回顾性总结,对三种... 目的:比较应用近红外线、高频超声、钼靶x—ray各自对乳腺癌早期诊断的价值,探讨联合应用近红外线、高频超声、钼靶x—ray对乳腺癌早期诊断的价值。方法:对81例经近红外线扫描、经B超检查、钼钯X线检查的病例进行回顾性总结,对三种影像学方法在乳腺癌诊断中的价值和优缺点进行了分析比较。结论诊断符合率分别为:近红外线83%,B超92.5%,钼钯X线93%,联合应用96%。联合应用近红外线、高频超声、钼靶x—ray有助于提高乳腺癌的诊断率和判断手术范围及术后效果,具有较大的临床价值。 展开更多
关键词 乳腺癌 联合应用近红外线 高频超声 钼靶xray 早期诊断
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胞元结构X-Ray三维成像及其FEM模拟
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作者 杜凤山 Gao Y X +4 位作者 Hamilton R W 臧新良 Wang Y Lee P D Song Jim 《固体力学学报》 CAS CSCD 北大核心 2006年第4期399-402,共4页
采用微纳米X-Ray断面成像技术,通过对含有CaCl2生物淀粉膨化结构材料三维成像规律的研究,确定了胞元体结构形态,并分析了断层胞元分布规律.建立了带有微细孔洞结构材料三维几何描述模型,通过理论建模和数字编程实现了与非线性有限元的连... 采用微纳米X-Ray断面成像技术,通过对含有CaCl2生物淀粉膨化结构材料三维成像规律的研究,确定了胞元体结构形态,并分析了断层胞元分布规律.建立了带有微细孔洞结构材料三维几何描述模型,通过理论建模和数字编程实现了与非线性有限元的连接,分析了微米级胞体材料受载后的场变量分布. 展开更多
关键词 微纳米xray 胞无结构 非线性有限元模拟
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Xray Diffraction Data and Rietveld Structure Refinement for CeNi_5Sn
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作者 何维 曾令民 +1 位作者 区向丽 吴自勤 《Journal of Rare Earths》 SCIE EI CAS CSCD 1999年第3期234-236,共3页
The compound CeNi 5Sn was studied by means of X ray powder diffraction technique and refined by Rietveld method. It has a hexagonal structure with space group P 6 3/ mmc (No.194), Z =4, the lattice constant... The compound CeNi 5Sn was studied by means of X ray powder diffraction technique and refined by Rietveld method. It has a hexagonal structure with space group P 6 3/ mmc (No.194), Z =4, the lattice constants a =0 48912(3) nm, c =1 973(2) nm and D x=8 974 g·cm -3 . The Rietveld structural refinement was performed, leading to R p=0 138 and R wp =0 185. The figure of merit F N for the XRD data is F 30 =82 1(0 0068, 54). The X ray powder diffraction data are presented. 展开更多
关键词 Rare earths CeNi 5Sn x ray diffraction Rietveld structural refinement
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Crystal Structure and X-ray Powder Diffraction Data for Rare Earth Compound PrNiSn
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作者 吴世伟 曾令民 +3 位作者 谭立真 张丽萍 严嘉琳 郝建民 《Rare Metals》 SCIE EI CAS CSCD 1999年第1期56-60,共5页
The compound PrNiSn was studied by X ray powder diffraction technique. The crystal structure and the X ray diffraction data for this compound at room temperature were reported. The compound PrNiSn is orthorhombic wi... The compound PrNiSn was studied by X ray powder diffraction technique. The crystal structure and the X ray diffraction data for this compound at room temperature were reported. The compound PrNiSn is orthorhombic with lattice parameters a =0.74569(3) nm, b =0.76851(5) nm, c =0.45676(8) nm, V =0.26176 nm 3, Z =4 and D x=8.076 g·cm -3 , space group Pna2 1(33). The figure of merit F N for the compound is F 30 =54 (0.0093, 60). 展开更多
关键词 PrNiSn x ray diffraction data Crystal structure
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X-ray Powder Diffraction Data and Structural Parameters for Compound NdFe_0.6Sb_2
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作者 曾令民 覃文 +2 位作者 吴世伟 郝建民 农亮勤 《Rare Metals》 SCIE EI CAS CSCD 1997年第2期49-53,共5页
The compound NdFe 0.6 Sb 2 was studied by means of X ray powder diffraction. The X ray powder diffraction data and structural parameters demonstrated that this compound is of the tetragonal structure with space... The compound NdFe 0.6 Sb 2 was studied by means of X ray powder diffraction. The X ray powder diffraction data and structural parameters demonstrated that this compound is of the tetragonal structure with space group P4/nmm, Z =2 and D x=7.615 g·cm -3 . The lattice parameters are a =0.43499 (1) nm and c =0.97083 (4) nm. Refinement was performed with 42 reflections. 展开更多
关键词 x ray powder data NdFe 0.6 Sb 2 Crystal structure
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COMPARISON OF BONE MASS IN FOREARM,LUMBAR VERTEBRA AND HIP BY SINGLE AND/OR DUAL ENERGY X-RAY ABSORPTIOMETRY
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作者 秦明伟 林守清 +4 位作者 宋忠良 田均平 陈凤领 严洪珍 葛秦生 《Chinese Medical Sciences Journal》 CAS CSCD 1999年第2期117-120,共4页
OBJECTIVE: Bone mineral density (BMD) was measured in normal Chinese women with single X-ray absorptiometry (SXA) and dual energy X-ray absorptiometry (DEXA). These two methods were compared to evaluate the sensitivit... OBJECTIVE: Bone mineral density (BMD) was measured in normal Chinese women with single X-ray absorptiometry (SXA) and dual energy X-ray absorptiometry (DEXA). These two methods were compared to evaluate the sensitivity in reflecting bone loss. METHODS: Measurements were performed in 300 women aged 20 to approximately 79 (5 for each age). The 8mm distal, 1/4 distal, ultra distal site of the nondominant forearm were measured with SXA; the AP spine (L2-4), right femoral neck (Neck), Ward's triangle (Ward) and trochantor (Troch) were measured with DEXA. Ten women had 5 repeated measurements to evaluate the reproducibility of the equipments. RESULTS: The BMD peak for Neck and Ward was found between age 20 to approximately 29, for ultra distal and L2-4 at age 30 to approximately 39, for 8mm distal, 1/4 distal and Troch at age 40 to approximately 49. After reaching the peak values, BMD at all sites decreased with increasing age. The highest rate of yearly loss of BMD was at 8mm distal. Results of measurement showed significant correlation between SXA and DEXA. Comparing with premenopausal women, the bone loss rate in postmenopausal women was faster and highest up to 11 to approximately 15 years and the highest rate was at the Ward. CONCLUSION: The present study gives the normal values of BMD at seven sites for normal Chinese women. The ages of BMD peak were different at seven sites. The yearly loss of BMD was highest at 8mm distal, it seemed to be the sensitive region for bone loss with age. The postmenopausal women had highly significantly loss bone mass than the premenopausal women. Comparing with premenopause, postmenopause BMD for Ward's triangle with DEXA seemed to be most sensitive to the effect of menopause. 展开更多
关键词 bone density osteoporosis post menopause densitometry x ray
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DIFFERENTIAL SCANNING CALORIMETRY AND X-RAY DIFFRACTION STUDIES ON AGING BEHAVIOR OF Zn-Al ALLOYS 被引量:2
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作者 X.L. Xu, Z. W. Yu, S.J. Ji, J.C. Sun and Z.K. Hei (Dalian Maritime University, Dalian 116024, China) 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2001年第2期109-114,共6页
Decomposition processes of the quenched Zn-Al alloys were studied by differential scanning calorimetry (DSC), X-ray diffraction (XRD) and transmission electron microscopy (TEM). The results show that the stabilities o... Decomposition processes of the quenched Zn-Al alloys were studied by differential scanning calorimetry (DSC), X-ray diffraction (XRD) and transmission electron microscopy (TEM). The results show that the stabilities of supersaturated solid solution (SSS) of Zn-Al alloy and α' phase formed by quenching would reduce with the increase of Zn content and the precipitation of η-Zn phases even when aging at ambient temperature, so that the exothermic precipitation peak in DSC curve would disappear. The activation energy of the η-Zn precipitation and the reaction enthalpy were calculated and measured. The kinetics of α' decomposition or η-Zn formation was determined by XRD. The microstructure change during aging was observed by TEM. 展开更多
关键词 Aging of materials Aluminum alloys Differential scanning calorimetry x ray diffraction
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X-ray Powder Diffraction Data and Crystal Structure of NiSbY
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作者 曾令民 李均钦 +2 位作者 张丽萍 庄应烘 郝建民 《Rare Metals》 SCIE EI CAS CSCD 1996年第1期67-70,共4页
X-ray powder diffraction data and crystal structure of NiSbY compound were studied by X-ray powderdiffraction. The compound belongs to the space group F43 m with MgAgAs structure type, and the parameters Z=4, a=0.6307... X-ray powder diffraction data and crystal structure of NiSbY compound were studied by X-ray powderdiffraction. The compound belongs to the space group F43 m with MgAgAs structure type, and the parameters Z=4, a=0.63075(2) nm. 展开更多
关键词 ANTIMONY Crystal structure DIFFRACTION NICKEL x rays YTTRIUM
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Nested grazing incidence optics for x ray detection
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作者 李林森 强鹏飞 +5 位作者 盛立志 刘永安 刘哲 刘舵 赵宝升 张淳民 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第10期152-156,共5页
Grazing incidence optics (GIO) is the most important compound in an x-ray detection system; it is used to concentrate the x-ray photons from outer space. A nested planar GIO for x-ray concentration is designed and d... Grazing incidence optics (GIO) is the most important compound in an x-ray detection system; it is used to concentrate the x-ray photons from outer space. A nested planar GIO for x-ray concentration is designed and developed by authors in this paper; planar segments are used as the reflection mirror instead of curved segments because of the simple process and low cost. After the complex assembling process with a special metal supporter, a final circle light spot of φ 12 mm was obtained in the visible light testing experiment of GIO; the effective area of 1710.51 mm^2@ 1 keV and 530 mm^2@8 keV is obtained in the x-ray testing experiment with the GIO-SDD combination, which is supposed to be a concentrating detector in xray detection systems. 展开更多
关键词 x ray detection grazing incidence optics planar segments concentrating detector
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X-ray elastic constant determination and residual stress of two phase TiAl-based intermetallic alloy
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作者 郭富安 张永刚 +2 位作者 陈昌麒 ZHANG Yong-gong CHEN Chang-qi 《中国有色金属学会会刊:英文版》 CSCD 2001年第2期205-209,共5页
To evaluate the residual stress in TiAl based alloys by X ray diffraction, X ray elastic constants (REC) of a γ TiAl alloy were determined. From these results, the stress state of a given phase in a duplex TiAl based... To evaluate the residual stress in TiAl based alloys by X ray diffraction, X ray elastic constants (REC) of a γ TiAl alloy were determined. From these results, the stress state of a given phase in a duplex TiAl based alloy under a uniaxial tensile loading has been characterized by X ray diffraction. The results show that the X ray elastic constants and the microscopic stresses of the given phase are different from the apparent elastic constants and the macroscopic stresses of the alloy. The reason of the different distribution of the alloy was also discussed. [ 展开更多
关键词 TiAl based alloy x ray diffraction technique x ray elastic constant duplex structure residual stress
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The Characteristics and Dynamic Changes of X Ray Chest Film in 50 Patients with Severe Acute Respiratory Syndrome
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作者 马俊义 李智岗 +2 位作者 赵增毅 孙武装 王颖 《Chinese Journal of Integrated Traditional and Western Medicine》 2003年第4期296-298,共3页
关键词 in The Characteristics and Dynamic Changes of x ray Chest Film in 50 Patients with Severe Acute Respiratory Syndrome SARS
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BACKGROUND RECTIFICATION AND FEATURE EXTRACTION OF IMAGE IN A SPOT WELD OF AL ALLOY X-RAY DETECTION
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作者 T.Gang J.Zhang M.B.Zhang and F.X.Liu (1)AWPT National Key.,HIT,Harbin 15001,China 2)State 159 Factory,China) 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2000年第1期75-79,共5页
A primary study on Processing in X - ray inspection of spot weld for aluminum alloy spot welding,in- cluding for background simulation,acquisition of ideal binary image, and extraction and identifi- cation of defec... A primary study on Processing in X - ray inspection of spot weld for aluminum alloy spot welding,in- cluding for background simulation,acquisition of ideal binary image, and extraction and identifi- cation of defect features was presented. 展开更多
关键词 x - ray detection image processing spot weld aluminium alloy
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探讨能量色散型X—ray测试仪不同准直器对检测项链中贵金属含量的影响
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作者 王燕 刘林林 《现代测量与实验室管理》 2016年第5期3-7,共5页
本文使用能量色散型X射线荧光光谱分析仪(简称X—ray测试仪)在确保仪器其他条件均相同的情况下,通过设置不同的准直器检测同一项链的同一位置,结果显示准直器的大小对测试结果有较显著的影响。
关键词 xray 准直器 项链
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