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241 个结果
  • 简介:Aserialofprotonatedandlayeredtransitionmetaloxides,includinglayeredHTaWO6,HNbMoO6aswellasHNbWO6,weresynthesizedbysolid-statereactionandion-exchange.ThelayeredHTaWO6hasbeensystematicallystudiedasasolidacidtorealizethedehydrationoffructoseto5-hydroxymethylfurfural(HMF).ThetransitionmetaloxidesampleswerecharacterizedwithICP-OES,EDS,XRD,XPS,SEM,TGA,FT-IR,N2adsorption–desorptionandNH3-TPD.Theinfluentialfactorssuchasreactiontemperature,reactiontime,solvent,catalystamountandsubstrateconcentrationweredeeplyinvestigated.Theoptimizedfructoseconversionrateof99%withHMFyieldof67%wereachievedafter30minat140°Cindimethylsulfoxide.

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  • 简介:粉状的LiCr0.35Mn0.65O2的电的传导性在温度范围在高压力下面被测量直到26.22GPa由使用一个钻石铁砧房间的300413K。电导率和激活热含量在5.36GPa和21.66GPa不连续地变化,这被发现。在压力范围1.105.36GPa,压力增加激活热含量并且减少散布的搬运人,它最后导致传导性增加。在压力范围6.3221.66GPa和22.6026.22GPa,有压力增加的激活热含量减少,它有积极贡献到电的电导率增加。二导致压力的结构的阶段转变被发现由在原处在高压力下面X光检查衍射,它导致电导率和激活热含量的不连续的变化。

  • 标签: 电导率测量 高压力 相变行为 压力范围 活化焓 温度范围
  • 简介:WepresentthetemperaturedependentelectricaltransportmeasurementsofAg/Si(111)-(√3×√3)R30°bytheinsitumicro-four-pointprobemethodintegratedwithscanningtunnelingmicroscopy.Thesurfacestructurecharacterizationsshowhexagonalpatternsatroomtemperature,whichsupportstheinequivalenttriangle(IET)model.Ametal-insulatortransitionoccursat-115K.Thelowtemperaturetransportmeasurementsclearlyrevealthestronglocalizationcharacteristicsoftheinsulatingphase.

  • 标签: surface CONDUCTIVITY METAL-INSULATOR transition LOCALIZATION SCANNING
  • 简介:InsituhighpressureenergydispersiveX-raydiffractionmeasurementsonlayeredperovskite-likemanganateCa3Mn2O7underpressuresupto35GPahavebeenPerformedbyusingdiamondanvilcellwithsynchrotronradiation.Theresultsshowthatthestructureoflayeredperovskite-likemanganateCa3Mn2O7isunstableunderpressureduetotheeasycompressionofNaCl-typeblocks.ThestructureofCa3Mn2O7underwenttwophasetransitionsunderpressuresintherangeof0-35GPa.Onewasatabout1.3GPawiththecrystalstructurechangingfromtetragonaltgoorthorhombic.Theotherwasatabout9.5GPawiththecrystalstructurechangingformorthorhombicbacktoanothertetragonal.

  • 标签: 高压 X射线衍射 Ca3Mn2O7 钙钛矿结构 锰酸盐晶体 相变
  • 简介:Ahomologousseriesof4’-methylphenyl4"-[(4-alkoxy-2,3,5,6-tetrafluorophenyl)ethynyl]-benzoateshavebeensynthesized.Polarizingmicroscopictexturalobservationshowsthatsuchcompoundsexhibitenantiotropicnematicphase.

  • 标签: Liquid crystal 1 4-tetrafluorophenylene SYNTHESIS NEMATIC
  • 简介:Byusingsurfaceeffects(Augerelectronspectroscopy,X-rayphotoelectronspectroscopy,polarKerreffect)andvolumeeffects(magnetization,torquecurve)thephysicalprocessofsurfaceoxidationofrareearth-transitionmetalamorphousmagneto-opticalthinfilmswasstudiedinthispaper.Therareearthelementsoxidizepreferentiallyandrichatthefilmsurface,andthetransitionmetalsdepleteinoxidationlayer.Fe2O3inthesurfaceoxidationlayercontributestotheplanarmagnetization,andtherebytheanomalouspeakappearsnear180°onthetorquecurvesandtheamplitudeofthepeaksisrelatedtothedepthofsurfaceoxidationlayers.Theironbondstooxygeneasierthanthecobolt.RE-Comagneto-optiealthinfilmshavegoodpropertiesofresistancetooxidationandhumidity.

  • 标签: Rare earth Magneto-o tical THIN FILM
  • 简介:AnovelfittingprocedureisproposedforabetterdeterminationofH2rovibrationaldistributionfromtheFulcher-abandspectroscopy.WehaverecalculatedthetransitionprobabilitiesandtheresultsshowthattheydeviatefromFranck-Condonapproximationespeciallyforthenon-diagonaltransitions.Wealsocalculatedthecompletesetsofvibrationallyresolvedcrosssectionsforelectronimpactd3∏u-X3∑gtransitionbasedonthesemi-classicalGryzinskitheory.AnexampleofexperimentalstudyconfirmsthatcurrentapproachprovidesatoolforabetterdiagnosticsofH2rovibrationaldistributioninelectronicgroundstate.

  • 标签: 低温等离子体 转振激发 氢气分子 Fulcher-α波段分光镜
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  • 简介:AbstractBackground:MicroRNA-20a (miR-20a) is dysregulated in many types of malignancies, including human hepatocellular carcinoma (HCC), but its expression level and functional significance in HCC are still disputed. We aimed to study the role of miR-20a-5p in HCC and its downstream molecular mechanisms.Methods:We used real-time polymerase chain reaction to detect the expression of miR-20a-5p and runt-related transcription factor 3 (RUNX3) in HCC and paraneoplastic tissue, transfected Huh7 and highly metastatic human hepatocellular carcinoma (MHCC97H) cells. A live cell workstation was used to observe the proliferation and migration of transfected cells. The invasiveness of transfected cells was verified by Transwell assay. Cell apoptosis was detected by flow cytometry. The expression levels of proteins after transfection were measured using simple western immunoblot measurements. Gene expression profiles between HCC and normal samples were obtained from The Cancer Genome Atlas. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment results were processed by the database for annotation, visualization and integrated discovery. Potential target genes of miR-20a-5p were predicted to further investigate how miR-20a-5p regulates epithelial-mesenchymal transition (EMT) in HCC.Results:MiR-20a-5p was significantly highly expressed in HCC tissues, and overexpression of miR-20a-5p significantly promoted HCC cell proliferation, migration, and invasion and inhibited apoptosis in vitro. The protein expression of E-cadherin was decreased and that of vimentin was increased after overexpression of miR-20a-5p in HCC cells. We discovered the intersection of genes from miRDB, miR TarBase, and TargetScan, obtained 397 target genes and finally focused on RUNX3. RUNX3 was not only reduced in HCC specimens but also drastically reduced in HCC cells overexpressing miR-20a-5p. RUNX3 expression decreased with elevated miR-20a-5p, which activated downstream EMT signaling and promoted cell proliferation, migration, and invasion.Conclusions:Since RUNX3 is involved in EMT in HCC, as proven by previous research, our findings provide further evidence for a novel regulatory pathway comprising the miR-20a/RUNX3/EMT axis that upregulates EMT signaling and enhances the migration of HCC cells.

  • 标签: Epithelial-mesenchymal transition Hepatocellular carcinoma miR-20a-5p RUNX3
  • 简介:AbstractBackground:Although increasing abnormal expression of circular RNAs (circRNAs) has been revealed in various cancers, there were a small number of studies about circRNAs in gastric cancer (GC). Here, we explored the expression and function of a novel circRNA, circ_0049447, in GC.Methods:A total of 80 GC tissues and non-tumorous tissues were collected from the First Affiliated Hospital of China Medical University. And all cells were cultured with 10% fetal bovine serum and incubated at 37°C and 5% CO2. The expression of circ_0049447 was quantified by real-time polymerase chain reaction. The biological function of circ_0049447 on proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) was evaluated by cell counting kit-8 (CCK-8), colony formation assay, transwell migration and invasion assay, and Western blotting. Luciferase report assay was used to verify the direct binding between circ_0049447 and predicted microRNA (miRNA). Furthermore, a xenograft mouse model was used to validate the function of circ_0049447 in vivo.Results:We demonstrated that circ_0049447 was downregulated in GC (P < 0.001). The area under the receiver operating characteristic curve reached 0.838, while sensitivity was 82.3% and specificity was 77.2%. CCK-8 and colony formation assay showed that overexpression of circ_0049447 could inhibit the proliferation (P < 0.05). Transwell migration and invasion assay showed upregulated circ_0049447 could impede migration in GC cells (P < 0.05). In addition, overexpression of circ_0049447 could impede GC cell EMT. Upregulation of miR-324-5p in GC specimens and direct binding between miR-324-5p with circ_0049447 proven by luciferase reporter assay indicated that circ_0049447 may inhibit GC by sponging certain miRNA.Conclusion:Circ_0049447 acts as a tumor suppressor in GC through reducing proliferation, migration, invasion, and EMT, and it is a promising biomarker for diagnosis.

  • 标签: Gastric cancer CircRNAs Biomarker
  • 简介:AbstractBackground:When utilizing the retrosigmoid approach (RA), accurately identifying the transverse and sigmoid sinus transition (TSST) is a key procedure for neurosurgeons, especially in developing countries restricted by the lack of expensive devices, such as the neural navigation system and the three-dimensional volumetric image-rendered system. Before operations, a computed tomography scan is a common and cost-effective method of checking patients who suffer lesions located at the cerebellopontine angle. Therefore, we present a technique using only high-resolution computed tomography to identify the transverse and sigmoid sinus transition.Methods:This retrospective study included 35 patients who underwent retrosigmoid approach operations to resect an acoustic neurinoma with the assistance of our technique. In brief, our technique contains 4 steps: (1) All patients’ 1-mm, consecutive, high-resolution computed tomographic images that clearly displayed landmarks, such as the inion, lambdoid suture, occipitomastoid suture, and the mastoid emissary foramen, were investigated initially. (2) We selected two particular slices (A and B) among all of these high-resolution computed tomographic images in which scanning planes were parallel with the line drawn from the root of the zygoma to the inion (LZI). Slice A contained both the root of the zygoma and the inion simultaneously, and slice B displayed the mastoid emissary foramen. (3) Four points (α, β, γ, δ) were arranged on slices A and B, and point α was located at the inner surface of the skull, which represents the posterior part of the sulci of the sigmoid sinus. Point β was located at the outer surface of the skull, and the line connecting them was perpendicular to the bone. Similarly, on slice B, we labeled point γ as the point that represents the posterior part of the sulci of the sigmoid sinus at the inner surface and point δ as the point located at the outer surface of the skull, and the line connecting them was also perpendicular to the bone. The distances between point β and the lambdoid suture/occipitomastoid suture and between point δ and the mastoid emissary foramen were calculated for slices A and B, respectively. (4) During the operation, a line indicating the LZI was drawn on the bone with ink when the superficial soft tissue was pushed away, and this line would cross the lambdoid suture/occipitomastoid suture. With both the crosspoint and the distance obtained from the high-resolution CT images, we could locate point β. We also used the same method to locate point δ after revealing the mastoid emissary foramen. The line connecting point β and point δ indicated the posterior border of the sigmoid sinus, and the intersection between the line and LZI indicated the inferior knee of the transverse and sigmoid sinus transition (TSST).Results:All 35 patients underwent the RA craniectomies that were safely assisted by our technique, and neither the sigmoid sinus nor the transverse sinus was lacerated during the operations.Conclusion:Our cost-effective technique is reliable and convenient for identifying the transverse and sigmoid sinus transition (TSST) which could be widely performed to guarantee the safety of RA craniectomy.

  • 标签: Retrosigmoid approach Transverse and sigmoid sinus transition Lambdoid suture Occipitomastoid suture LZI Mastoid emissary foramen
  • 简介:AIMTo学习discoidin象我一样domaincontaining蛋白质3的效果(EDIL3)在人的透镜的增长和上皮间充质的转变(EMT)上的弄空上皮的房间(LEC).METHODSRNA干扰被用来在vitro在人的LEC禁止EDIL3的表示。房间的形态学用一台转换显微镜被观察。房间增长用EdU工具包被估计。房间移植用Transwell房间被调查,LEC的EMT用共焦的显微镜并且西方的弄污被估计。转变生长因素(TGF)小径用数据显示出的西方的blotting.RESULTSThe被调查那个silencingEDIL3表达式改变了LEC形态学并且压制了LEC增长(P<0.05)并且移植(P<0.01)。而且,西方的弄污的结果证明那EDIL3弄空减少了光滑的肌肉肌动朊的表示(-SMA)(P<0.001)并且vimentin(P<0.01),当增加时E-cadherin的表示(P<0.001)。EDIL3弄空能压制Smad2的phosphorylation(P<0.01)并且Smad3(P<0.01)并且exracellular信号的激活调整了kinase(英皇家空军之阶级最低之兵)(P<0.05).CONCLUSIONThe调查结果显示EDIL3可能经由TGF小径在LEC参予增长和EMT并且可以是为以后的囊opacification的处理的一个潜在的治疗学的目标。

  • 标签: discoidin 象我一样包含域的蛋白质 3 转变生长因素 上皮间充质的转变 人的透镜上皮的房间
  • 简介:Thispaperintroducedthebasictheoryandalgorithmofthesurrogatedatamethod,whichproposedarigorouswaytodetecttherandomandseeminglystochasticcharacteristicsinasystem.TheGaussiandataandtheRosslerdatawereusedtoshowtheavailabilityandeffectivityofthismethod.Accordingtotheanalysisbythismethodbasedontheshort-circuitingcurrentsignalsundertheconditionsofthesamevoltageanddifferentwirefeedspeeds,itisdemonstratedthattheelectricalsignalstimeseriesexhibitapparentlyrandomnesswhentheweldingparametersdonotmatch.However,theelectricalsignalstimeseriesaredeterministicwhenamatchisfound.Thestabilityofshort-circuitingtransferprocesscouldbejudgedexactlybythemethodofsurrogatedata.

  • 标签: 替代数据法 时间序列 电信号 随机信号 测试 随机特性
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