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141.
Integration between a hand-held mass spectrometry desorption probe based on picosecond infrared laser technology (PIRL-MS) and an optical surgical tracking system demonstrates in situ tissue pathology from point-sampled mass spectrometry data. Spatially encoded pathology classifications are displayed at the site of laser sampling as color-coded pixels in an augmented reality video feed of the surgical field of view. This is enabled by two-way communication between surgical navigation and mass spectrometry data analysis platforms through a custom-built interface. Performance of the system was evaluated using murine models of human cancers sampled in situ in the presence of body fluids with a technical pixel error of 1.0 ± 0.2 mm, suggesting a 84% or 92% (excluding one outlier) cancer type classification rate across different molecular models that distinguish cell-lines of each class of breast, brain, head and neck murine models. Further, through end-point immunohistochemical staining for DNA damage, cell death and neuronal viability, spatially encoded PIRL-MS sampling is shown to produce classifiable mass spectral data from living murine brain tissue, with levels of neuronal damage that are comparable to those induced by a surgical scalpel. This highlights the potential of spatially encoded PIRL-MS analysis for in vivo use during neurosurgical applications of cancer type determination or point-sampling in vivo tissue during tumor bed examination to assess cancer removal. The interface developed herein for the analysis and the display of spatially encoded PIRL-MS data can be adapted to other hand-held mass spectrometry analysis probes currently available.

Integration between a hand-held mass spectrometry desorption probe based on picosecond infrared laser technology (PIRL-MS) and an optical surgical tracking system demonstrates in situ tissue pathology from point-sampled mass spectrometry data.  相似文献   
142.
煤粉在热分解过程中比表面积和孔隙结构的变化   总被引:17,自引:7,他引:17  
用氮气等温吸附(77K)方法测量了四种不同煤粉在热分解过程中的BET比表面积和孔隙结构。结果表明,不同煤种的比表面积在热分解过程中其变化有着相似的规律。在热分解温度低于500℃时,煤粉所释放的挥发份主要来自煤粒外表面。当热分解温度高于500℃后,煤粉释放出的挥发份主要来自煤粒内部深处。在800℃时,由于煤的塑性,煤粒的部分孔减小和关闭,使其比表面积以及孔隙明显减少。在热分解温度高于850℃后,煤粉的比表面积随温度升高而急剧增大。  相似文献   
143.
144.
以D-核糖为原料,合成了1,4-脱水一双(氧特丁基二甲基甲硅烷基)-α-D-吡喃核糖(ADSR)和1,4-脱水-2,3-氧-亚异丙基-α-D-吡喃核糖(AIRP),研究了它们在SbCl5催化下的开环共聚合反应,并测定了共聚产物的比旋光度、分子量及1H、13CNMR谱。结果表明,尽管AIRP在均聚中总是得到单一的1-4β结构产物,而在共聚产物中,AIRP结构单元则为1—4β和1-5α的混合结构。同时发现,聚合温度对共聚物的产率和立体结构均有较大的影响。  相似文献   
145.
刘延秋  田秋 《结构化学》1994,13(3):163-169
本文用自旋捕捉与ESR技术相结合的方法研究了ZnS胶体溶液中某些无机盐光化学过程中产生的无机阴离子自由基,并对自由基产生的机理进行了讨论  相似文献   
146.
Three new serratane triterpenoids, (3α,14α,15α,21α)‐3,14,15,21,29‐pentahydroxyserratan‐24‐oic acid ( 1 ), (3α,21β)‐serrat‐14‐ene‐3,21,24,30‐tetraol ( 2 ), and (3α,21α)‐serrat‐14‐ene‐3,21,24,29‐tetraol ( 3 ), were isolated from Phlegmariurus squarrosus, together with eight known compounds. Their chemical structures were elucidated on the basis of in‐depth spectroscopic analyses.  相似文献   
147.
Luo X  Lu Z  Xi J  Wu Z  Zhu W  Chen L  Qiu X 《The journal of physical chemistry. B》2005,109(43):20310-20314
The preparation and physical characterization of a poly(vinylidene fluoride)-graft-poly(styrene sulfonic acid) (PVDF-g-PSSA) membrane prepared by a solution-grafting method were described. These membranes exhibited high conductivity with a value 3.22 x 10(-2) S/cm at 30 degrees C. ICP studies revealed that the PVDF-g-PSSA membrane showed dramatically lower vanadium ion permeability compared to Nafion 117. Trivalent vanadium ions had the highest permeability through all these membranes in contrast to pentavalent vanadium ions with the lowest. The VRB with the low-cost PVDF-g-PSSA membrane exhibited a higher performance than that with Nafion 117 under the same operating conditions, and its energy efficiency reached 75.8% at 30 mA/cm(2). The performance of VRB with the PVDF-g-PSSA membrane can be maintained after more than 200 cycles at a current density of 60 mA/cm(2).  相似文献   
148.
运用循环伏安和阶跃电位方法研究了Ni(OH)2粉末靶直流溅射沉积的NiOxHy薄膜电致变色特性.结合实时的光透射-时间变化,发现着色后的薄膜在零外电势下有一自发的消色过程,该过程可能对应着Li 的自发注入。着色没有自发过程,获取了着消色状态Ni2p3/2和O1s的XPS谱,表明在着色态镍被氧化,消色态镍被还原,相应地氧的化学环境发生改变.  相似文献   
149.
A new triterpenoid, fornicatin C (= (3β)‐3‐hydroxy‐18(13 → 12β)‐abeo‐lanosta‐13(17),24‐dien‐18‐oic acid; 1 ), was isolated from the fruiting bodies of Ganoderma fornicatum, together with the known compounds fornicatin A ( 2 ) and fornicatin B ( 3 ), among other constituents. The structure of 1 was elucidated by means of spectroscopic techniques, and those of 2 and 3 were identified by comparing their spectroscopic data with those reported in the literature.  相似文献   
150.
Thermal decomposition of dimethyl azo(bisisobutyrate) in a solution containing C(60) produced 1,4- and 1, 16-di(2-carbomethoxy-2-propyl)-1,x-dihydro[60]fullerenes in yields of 21% and 27%, respectively, based on reacted C(60). The structure of this first 1,16-dialkyl-1,16-dihydro[60]fullerene was assigned from (13)C 2D INADEQUATE NMR spectra. The 1,16-isomer has first and second electrochemical reduction potentials shifted positively by 0. 18 V relative to those of the 1,4-isomer. From the close similarity of all spectral, chromatographic, and electrochemical data, the previously unassigned isomer of 1,x-di(2-cyano-2-propyl)-1, x-dihydro[60]fullerene, which was obtained from azo(bisisobutyronitrile) and C(60), is also a 1,16-isomer.  相似文献   
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