Fast X-ray imaging beamline at SSRF

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.

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

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.

上海光源储存环X-ray针孔相机系统设计

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。

PIXE分析浙江德清火烧山窑址出土原始瓷

浙江是原始瓷的重要产地,德清火烧山窑址是目前已知的唯一一处西周晚期至春秋晚期的原始瓷窑址,也是目前已发掘最早的纯烧原始瓷的窑址,对于探索中国早期青瓷的烧造技术具有极其重要的意义。选取早期(西周晚期到春秋初期)样品18个,中后期(春秋中期后段)样品15个,晚期(春秋晚期后段)样品17个,进行质子激发X射线荧光(Proton Induced X-ray Emission,PIXE)分析。因子分析用来研究这些不同时期烧造的原始瓷原料来源和相互关系。结果表明,晚期产品所用胎料、釉料与早期产品不同,与中后期产品相同。

Synthesis and characterization of copolyimides from bis(3,4-dicarboxyphenyl)dimethylsilane dianhydride

The silicon-containing poly (amic acid)s were synthesized from bis (3, 4-dicarboxyphenyl) dimethylsilane dianhydride (SIDA), pyromellitic dianhydride (PMDA) and 4,4′-oxydianiline (4,4'-ODA) in N, N-dimethylacetamide (DMAc). The poly (amic acid) films were obtained by solution-cast method from DMAc solutions and thermally converted into transparent, flexible and tough polyimide films. The wide-angle X-ray diffraction diagrams revealed that all the polyimides possessed amorphous character, and the regulation of those polyimides were decreased with the increase of the molar ratio of SIDA to PMDA. Differential scanning calorimeter measurements showed that the introduction of SIDA to polyimide backbone would make glass transition temperature shift to lower temperature. Thermogravimetric analyses indicated that the silicon-containing polyimides lowered decomposition temperature as compared with PMDA/4, 4′-ODA polyimides. However, UV-visible transmission and reflection spectra showed that the optical transparency of silicon-containing polyimide thin films was superior to that of PMDA/4, 4'-ODA polyimide thin films.

Fe_(100-x)Co_x系合金超细粉末的制备和磁性

用机械合金化方法制备了Fe100-xCox系超细粉末(x=15,35,50).对各样品进行了X-ray衍射谱的分析;用柯西分布公式计算了材料的晶粒尺寸,约为9～12nm;用最小二乘法计算了材料的晶格常数a;测量了不同成分样品的磁滞回线.研究发现,当x=15,35,50时,材料均呈现了α-Fe的单相,并且样品有较低的矫顽力Hc和较高的饱和磁化强度Ms.用趋近饱和定律计算了样品的有效磁晶各向异性常数Ke和原子磁矩μ.研究表明,样品具有优良软磁材料的内禀性能.

厚钢管X射线图像中焊缝区域的检测

由于传统焊缝区域检测算法难以准确提取模糊和对比度低的厚钢管焊缝区域,提出一种新的基于鲁棒PCA模型的焊缝区域检测算法,该算法能克服传统方法的不足,并能准确提取焊缝区域.首先,收集一序列X射线图像,并对其进行空域对齐及亮度归一化预处理.其次,计算得到系列图像的背景图像,并将背景图像与待测试X射线图像张成一个观测矩阵.最后,使用鲁棒PCA算法对观测矩阵进行低秩与稀疏分解,测试图像中的不均匀强度及噪声被消除,焊缝区域被凸显出来,通过全局阈值可将焊缝区域较好地分割出来.实验结果表明,该算法能较大地消除厚钢管X射线图像中噪声及不均匀强度分布带来的干扰、同时增强模糊的焊缝边缘及对比度低的区域,相比传统焊缝区域检测算法,具有更高的检测灵敏度(0.952)和精度(0.989),能更好地将模糊和对比度低的焊缝区域完整检测出来.

Soft X ray Diagnosis on Seed Development and Observation on Seed Germination and Seedling Growth in Artificial Hybridization in Cunninghamia and Cryptomeria

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.

Construction of a database of average cross-sections in Chinese proximal femurs

The process of constructing a database of average cross-sections in Chinese proximal femurs is described. The main goal of creating the database is for designing hip stems for Chinese patients. Methods for constructing the database are introduced. According to some existing software and programs developed by the authors, a database of average cross-sections in Chinese proximal femurs was built based on CT images of eighty femur-specimens. 3-D shape of a patient's proximal femurs can be reconstructed according to the database and X-ray radiographs. Theoretical analyses and results of clinical application indicate that the database can be used to design hip stems for Chinese patients.

INTERFACIAL BONDING IN AS DEPOSITED AND ANNEALED Co/C SOFT X RAY MULTILAYER MIRRORS

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.

A Straightforward Method of Calculating Finely the Soft X-Ray Spectra of Hydrogenlike Highly Ionized-States

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.

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

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。

胞元结构X-Ray三维成像及其FEM模拟

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.

X-ray Powder Diffraction Data and Crystal Structure of NiSbY

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.

X射线衍射法定性分析陶瓷釉中的铅和镉相

本研究运用X射线衍射技术对潮州市面陶瓷釉料的组成成分的物相样品进行了定性分析,结果显示,这些釉料样品中基本不含有毒的Pb、Cd氧化物等。

Extraction of metals from complex sulfide nickel concentrates by low-temperature chlorination roasting and water leaching

The recovery of valuable metals from complex sulfide concentrates was investigated via chlorination roasting followed by water leaching. A reaction process is proposed on the basis of previous studies and the results of our preliminary experiments. During the process, various process parameters were studied, including the roasting temperature, the addition of NH4Cl, the roasting time, the leaching time, and the liquid-to-solid ratio. The roasted products and leach residues were characterized by X-ray diffraction and vibrational spectroscopy. Under the optimum condition, 95% of Ni, 98% of Cu, and 88% of Co were recovered. In addition, the removal of iron was studied in the water leaching stage. The results demonstrate that this process provides an effective approach for extracting multiple metals from complex concentrates or ores. © 2017, University of Science and Technology Beijing and Springer-Verlag Berlin Heidelberg.

Preparation and catalytic activity of CO-resistant catalyst core-shell Au@Pt/C for methanol oxidation

Au@Pt core-shell nanoparticles were successfully synthesized by a successive reduction method and then assembled on Vulcan XC-72 carbon surface. Furthermore, its composition, morphology, structure, and activity towards methanol oxidation were characterized by UV-vis spectrometry, transmission electron microscopy (TEM), high-resolution TEM (HRTEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and cyclic voltammetry (CV). Results reveal that Au@Pt/C catalyst has better activity towards methanol oxidation than the pure platinum prepared under the same conditions. When the atomic ratio of Au to Pt in the prepared Au@Pt/C catalyst is 1:2, this catalyst exhibits best electrocatalytic activity towards methanol oxidation in acidic media, and the peak current density on this catalyst is ~2.0 times higher than that on Pt/C catalyst. The better catalytic activity of Au@Pt/C results from its better resistance to toxic CO than Pt/C because the CO oxidation on Au@Pt/C is 60 mV more negative than the case on Pt/C. © The Nonferrous Metals Society of China and Springer-Verlag Berlin Heidelberg 2012.

Amine-functionalized low-cost industrial grade multi-walled carbon nanotubes for the capture of carbon dioxide

Industrial grade multi-walled carbon nanotubes(IG-MWCNTs) are a low-cost substitute for commercially purified multi-walled carbon nanotubes(P-MWCNTs). In this work, IG-MWCNTs were functionalized with tetraethylenepentamine(TEPA) for CO2capture. The TEPA impregnated IG-MWCNTs were characterized with various experimental methods including N2adsorption/desorption isotherms, elemental analysis, X-ray diffraction, Fourier transform infrared spectroscopy and thermogravimetric analysis. Both the adsorption isotherms of IGMWCNTs-n and the isosteric heats of different adsorption capacities were obtained from experiments. TEPA impregnated IG-MWCNTs were also shown to have high CO2adsorption capacity comparable to that of TEPA impregnated P-MWCNTs. The adsorption capacity of IG-MWCNTs based adsorbents was in the range of 2.145 to 3.088 mmol/g, depending on adsorption temperatures. Having the advantages of low-cost and high adsorption capacity, TEPA impregnated IG-MWCNTs seem to be a promising adsorbent for CO2capture from flue gas.

Relaxation of residual stresses in 20%SiC_w/6061Al composite as-extruded at high temperature

The residual stress in a 20%SiC w/6061Al composite as extruded was investigated by using X ray stress measurement method. It was found that, high residual stress existed in the composite and residual stress distribution in each direction are not uniform. Relaxation process of residual stress in the composite was dynamically measured during annealing at high temperature. It is verified that the relaxation of residual stress obeys the power law at high temperature. With the creep mechanism, the relaxation behavior of residual stresses at high temperature was analyzed. The results show that, the stress exponent and activation energy for stress relaxation of the composite are obviously higher than those of the matrix alloy.

特征X射线的量子特性

在论述X射线与特征X射线的产生的基础上,用量子理论分析了连续X射线谱与特征X射线谱产生的机理。结果表明,特征X射线的波长是由阳极靶物质的原子序数决定的;产生特征X射线的条件中必须包含一个临界激发电压。