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1.
在激光聚变实验中为了获取等离子体的重要信息,采用球面弯曲晶体成像谱仪来研究等离子体辐射的X射线,利用球面弯晶对X射线进行诊断而提供时间、空间、光谱分辨。该强聚焦晶体能增强信噪比,提高谱仪的空间分辨能力及立体角收集辐射能力。实验结果表明球面弯晶分析器对波长范围为0.2~0.4 nm的X射线其分辨率可达600~1 000,聚光效率在同样距离条件下比平晶分析器高一个数量级以上,适合于研究等离子体X射线光谱学。  相似文献   

2.
基于Bragg衍射理论,分析了超环面晶体分析器实现等离子体在子午和弧矢2个方向等比例放大成像的原理,采用云母作为衍射晶体,研制了对激光等离子体进行二维成像的超环面晶体分析器,其子午和弧矢曲率半径分别为290 mm和196 mm,用于衍射成像时的Bragg角度为54°.采用铬靶X射线源辐照金属网格目标,网格的网孔尺寸为200 μm×200 μm,通过超环面晶体分析器对铬靶Kα谱线的衍射,在X射线IP板上得到了网格的二维背光衍射图像,并与球面晶体分析器成像效果进行了对比.实验结果表明,与球面晶体分析器相比,超环面晶体分析器可实现在子午和弧矢2个方向等放大比的X射线背光成像,且分析器具有较高的空间分辨力,当光源尺寸为500 μm,成像放大倍数为1.86倍时,其空间分辨力达到67 μm.  相似文献   

3.
合肥光源X射线成像光束线和实验站设计   总被引:1,自引:0,他引:1  
在X射线成像光束线光学系统的设计基础上,对光束线的能量分辨率和光子通量进行了计算,并对双晶单色器第一块晶体的热载影响进行了模拟分析,同时利用波带片成像技术对实验站进行了设计,达到了60 nm的空间分辨率.结果表明光束线和实验站的设计能够满足X射线成像实验所需条件的要求.  相似文献   

4.
Schmidt型和Angel型的X射线成像系统通过仿生龙虾眼睛微通道结构实现全反射聚焦成像,相比传统的X射线成像方式,具有大视场、高空间分辨率和能量获取能力。研究两个龙虾眼基础结构模型,根据X射线掠入射反射理论,分析对比了Angel和Schmidt结构光线入射焦面时的分布和空间分辨率,并用tracepro软件建立模型仿真验证了两种结构龙虾眼在聚焦和成像时的接收光/发射光、最大值/十字臂、最大值/本底、十字臂/本底多个性能参数。理论分析和仿真结果表明,当龙虾眼透镜焦距较长和通道长宽比大约为50时,由于多次反射时的聚焦及成像,Schmidt模型比Angel模型的信噪比等主要参数高,空间分辨率低;当龙虾眼透镜焦距较短和通道长宽比大约为10时,由于单次反射时的聚焦及成像,Schmidt模型比Angel模型的信噪比等主要参数低,空间分辨率几乎一样。  相似文献   

5.
在"星光Ⅱ”激光装置上对Mg/Al混合材料平面靶和Mg/Al示踪层金盘靶进行三倍频激光打靶实验,用平面晶体谱仪测量靶材料发射的X光光谱,获取了示踪离子谱线实验数据.采用多组态Dirac-Fock方法计算所需原子参数,并在局域热动平衡条件下建立了双示踪离子谱线强度比随电子温度变化关系.在此基础上由双示踪元素等电子谱线法确定了Mg/Al混合材料平面靶及金盘靶激光等离子体的电子温度.  相似文献   

6.
一种新型的椭圆弯晶谱仪及其应用   总被引:2,自引:1,他引:1  
研制了一种新型的诊断0.2~2nm的激光等离子体X射线的聚焦型椭圆弯晶谱仪,根据椭圆光学自聚焦原理给出了弯晶谱仪的结构设计方案,创造性的提出了利用激光测距仪完成瞄准和测距两个功能的瞄准对中关键技术.通过在上海"神光Ⅱ"靶室上的装调及打靶实验,利用X-CCD成功的获取了谱线的图像,数据分析的结果证明实测谱线波长与理论值吻合.  相似文献   

7.
随着光学成像技术的发展,越来越多的成像技术应用于文物保护分析领域。其中,高光谱成像以其无损、非接触以及"图谱合一"的特点受到广泛关注。然而,受成像传感器的物理限制,现有高光谱图像空间分辨率远不及RGB三通道的高清数码相机,极大阻碍了文物高光谱数字化的应用。针对此问题,该文首先设计了一套文物高光谱数字化采集流程,便于规范化采集同一场景的RGB和高光谱图像数据,为后续融合增强带来便利。其次,提出了基于多尺度多支路的RGB和高光谱图像融合方法,通过设计空间光谱融合模块和细化模块,获取具有高空间和高光谱分辨率的数字化影像。实验结果表明,无论从主观视觉还是客观指标,提出的方法在保持光谱分辨率的同时,更好地提高了空间分辨率。  相似文献   

8.
在激光惯性约束聚变(Inertial Confinement Fusion,ICF)实验研究中,对X射线的产生和演化过程的诊断和对物理实验参量调控以及模拟程序的校验起着至关重要的作用.针对激光聚变产生的X射线在时间、空间和能谱方面的特点,结合当前物理实验对诊断技术的特殊要求,分别研发了以时间分辨、空间分辨和谱分辨为优势的X射线成像诊断设备.随着我国ICF实验研究的不断深入,国内X射线成像诊断设备的诊断能力得到了大幅度提升,某些自主提出的新概念诊断设备的技术性能甚至优于国外同类型诊断设备.  相似文献   

9.
微束X射线荧光分析谱仪及其对松针中元素的分布分析   总被引:1,自引:0,他引:1  
介绍了一种小型的微束X射线荧光分析谱仪,它是由导管X光透镜和能量色散X射线荧光分析谱仪组成.谱仪具有较高的空间分辨率和能量分辨率.使用本谱仪对松树针叶进行了微区分析,得出各种元素沿松针长度方向和横切面径向的分布规律.结果表明使用X光透镜的微束X射线荧光分析方法可以实现植物样品的微区分析,有助于进一步了解植物的生长与元素迁移的关系.  相似文献   

10.
 利用德国空间生物实验装置和自主研制的结晶室,在中国神舟八号飞船上进行了14种蛋白质的结晶实验,实验持续16.5d;同时使用相同结晶室在地面开展比对实验.结果表明:12种蛋白质在空间析出晶体,地面有11种;空间析出的6种蛋白质晶体可用于X-射线衍射实验,收得4种晶体的8套同步辐射衍射数据;地面有5种蛋白质晶体可用于X-射线衍射,收得3种晶体的5套同步辐射衍射数据,其中1套不完整.鸡蛋清溶菌酶空间晶体的初步衍射最高分辨率为1.16Å,地面晶体的为1.23Å.痢疾杆菌二磷酸四腺苷空间晶体初步衍射最高分辨率为1.75Å,地面晶体的为1.49Å,但是1颗空间晶体的晶型发生改变.衣原体蛋白酶样活化因子空间晶体的初步衍射最高分辨率为2.31Å,地面晶体未得到衍射数据.加拿大的17β-羟化类固醇脱氢酶复合物空间晶体的初步衍射最高分辨率为2.30Å,地面晶体未得到完整衍射数据.自主研制的结晶室的浸入式毛细管结构为国际上首次采用,具有无源和通用的优点,对汽相扩散结晶法具有良好的自然对流抑制效果.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

15.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

19.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

20.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

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