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381.
High‐throughput metabolic analysis is of significance in diagnostics, while tedious sample pretreatment has largely hindered its clinic application. Herein, we designed FeOOH@ZIF‐8 composites with enhanced ionization efficiency and size‐exclusion effect for laser desorption/ionization mass spectrometry (LDI‐MS)‐based metabolic diagnosis of gynecological cancers. The FeOOH@ZIF‐8‐assisted LDI‐MS achieved rapid, sensitive, and selective metabolic fingerprints of the native serum without any enrichment or purification. Further analysis of extracted serum metabolic fingerprints successfully discriminated patients with gynecological cancers (GCs) from healthy controls and also differentiated three major subtypes of GCs. Given the low cost, high‐throughput, and easy operation, our approach brings a new dimension to disease analysis and classification.  相似文献   
382.
Amorphous metal–organic frameworks (aMOFs) are an emerging family of attractive materials with great application potential, however aMOFs are usually prepared under harsh conditions and aMOFs with complex compositions and structures are rarely reported. In this work, an aMOF-dominated nanocomposite (aMOF-NC) with both structural and compositional complexity has been synthesized using a facile approach. A ligand-competition amorphization mechanism is proposed based on experimental and density functional theory calculation results. The aMOF-NC possesses a core–shell nanorod@nanosheet architecture, including a Fe-rich Fe-Co-aMOF core and a Co-rich Fe-Co-aMOF shell in the core–shell structured nanorod, and amorphous Co(OH)2 nanosheets as the outer layer. Benefiting from the structural and compositional heterogeneity, the aMOF-NC demonstrates an excellent oxygen evolution reaction activity with a low overpotential of 249 mV at 10.0 mA cm−2 and Tafel slope of 39.5 mV dec−1.  相似文献   
383.
Bi3.95Er0.05Ti3O12 (BErT) thin films were prepared on Pt/Ti/SiO2/Si and indium-tin-oxide (ITO)-coated glass substrates at room temperature by pulsed laser deposition. These thin films were amorphous with uniform thickness. Excellent dielectric characteristics have been confirmed. The amorphous BErT thin films deposited on the Pt/Ti/SiO2/Si and ITO-coated glass substrates exhibited almost the same dielectric constant of 52 with a low dielectric loss of less than 0.02 at 1 kHz. Meanwhile, the dielectric properties of the thin films had an excellent bias voltage stability and thermal stability. The amorphous BErT thin films might have potential applications in microelectronic and optoelectronic devices.  相似文献   
384.
针对He-Ne激光器旁侧光谱实验,开发了PE-7265锁相放大器的RS232,ADC1,ADC2,ADC3及CH1等接口,并将这些接口应用于该实验,得到了较好的实验结果。  相似文献   
385.
(±)-5-(10-Undecenethylamido)-acenaphthene was synthesized and successfully separated into enantiomers using chiral HPLC. The chemical structure of this compound was characterized by FT-IR, 1H NMR, MS spectra, and elemental analyses.  相似文献   
386.
新的高能注量电子束二极管系统   总被引:4,自引:4,他引:0       下载免费PDF全文
 为“闪光二号”加速器研制了新的二极管系统, 其电子束能注量比原二极管系统大3倍多。该系统由带滑闪开关的二极管、漂移管、脉冲磁场和真空靶室等部分组成, 通过减小阴极直径、增大轴向磁场强度和磁透镜比,调节滑闪开关距离和预脉冲开关气压等技术措施, 使二极管具有高能注量电子束输出的稳定工作状态, 在Marx发生器充电电压70kV条件下,在距阴极22cm的靶上获得了总能量21.5kJ、束斑直径52mm和能注量1.01kJ/cm2的电子束输出。  相似文献   
387.
 利用基于多光束干涉原理的等效腔模型导出了多层介质膜的反射系数的递推式,在此基础上证明了在中心频率附近,复反射系数可表示为中心频率处的反射系数与相位因子的积,进而导出了相位角的函数和反射时延的表达式。  相似文献   
388.
相对论电子束在角向磁场中产生硬X射线的实验研究   总被引:1,自引:0,他引:1       下载免费PDF全文
 在闪光二号加速器上用相对论电子束在低压气体和角向磁场中传输打靶的方法,进行了硬X射线产生的实验研究。在47cm传输距离上,电子束与钽靶作用,获得了面积积分剂量率为2.1×1010Gy·cm2/s的硬X射线辐射(能谱范围为20~120keV),在总的辐照面积上(4π方向)面积积分剂量达1 843Gy·cm2,X射线转换率达到108Gy·cm2/kJ。  相似文献   
389.
光敏电阻特性测定及其在自动照明灯中的应用   总被引:1,自引:0,他引:1  
用QJ23型直流单电桥测量光敏电阻的照度特性,实验结果与理论分析基本符合,并应用光敏电阻设计了自动照明灯电路。  相似文献   
390.
As a unique structural moiety in natural products, cinnamoyl lipids (CLs), are proposed to be assembled by unusual type II polyketide synthases (PKSs). Herein, we demonstrate that the assembly of the CL compounds youssoufenes is accomplished by a PKS system that uniquely harbors three phylogenetically different ketosynthase/chain length factor (KS/CLF) complexes (YsfB/C, YsfD/E, and YsfJ/K). Through in vivo gene inactivation and in vitro reconstitution, as well as an intracellular tagged carrier‐protein tracking (ITCT) strategy developed in this study, we successfully elucidated the isomerase‐dependent ACP‐tethered polyunsaturated chain elongation process. The three KS/CLFs were revealed to modularly assemble different parts of the youssoufene skeleton, during which benzene ring closure happens right after the formation of an ACP‐tethered C18 polyene. Of note, the ITCT strategy could significantly contribute to the elucidation of other carrier‐protein‐dependent biosynthetic machineries.  相似文献   
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