简介:Anovelgas-phaseelectrocatalyticcellcontainingalow-temperatureprotonexchangemembrane(PEM)wasdevelopedtoelectrochemicallyconvertCO2intoorganiccompounds.TwodifferentCu-basedcathodecatalysts(CuandCu-C)werepreparedbyphysicalvapordepositionmethod(sputtering)andsubsequentlyemployedforthegas-phaseelectroreductionofCO2atdifferenttemperatures(70-90℃).ThepreparedelectrodesCuandCu-CwerecharacterizedbyX-raydiffraction(XRD),X-rayphotoemissionspectroscopy(XPS)andscanningelectronmicroscopy(SEM).Asrevealed,CuispartiallyoxidizedonthesurfaceofthesamplesandtheCuandCu-Ccathodiccatalystswerecomprisedofaporous,continuous,andhomogeneousfilmwithnanocrystallineCuwithagrainsizeof16and8nm,respectively.Theinfluenceoftheappliedcurrentandtemperatureontheelectro-catalyticactivityandselectivityofthesematerialswasinvestigated.Amongthetwoinvestigatedelectrodes,thepureCucatalystfilmshowedthehighestCO2specificelectrocatalyticreductionratesandhigherselectivitytomethanolformationcomparedtotheCu-Celectrode,whichwasattributedtothehigherparticlesizeoftheformerandlowerCuO/Curatio.Theobtainedresultsshowpotentialinterestforthepossibleuseofelectrical「enewableenergyforthetransformationofCO2intovaluableproductsusinglowmetalloadingCubasedelectrodes(0.5mgCucm2)preparedbysputtering.
简介:摘要目的探讨血清中ApoAⅠ与HDL-C以及ApoB与LDL-C之间的的相关性。方法选取我院收治的34例高脂血症患者作为为观察组,以同期体检的健康成人35例作为对照组。分别检测甘油三酯、总胆固醇、高密度脂蛋白胆固醇和低密度脂蛋白胆固醇、载脂蛋白AⅠ与载脂蛋白B,然后通过统计学方法比较指标间的相关性。结果对照组ApoAⅠ与HDL-C以及ApoB与LDL-C之间均呈中等相关性,实验组ApoAⅠ与HDL-C呈中等相关性,ApoB与LDL-C之间存在显著相关性。结论载脂蛋白AⅠ与高密度脂蛋白具有相关性,载脂蛋白B与低密度脂蛋白同样具有相关性。
简介:研究表明含氟气体的性质决定了原子氟(F)的转化效率,通常在CxFy气体中x的值越大,氟(F)的转化效率也就会越高。所以C3F8(八氟丙烷)比C2F6(乙氟烷)具有更高的利用效率,更少的PFC(全氟化物)的排放。文章主要研究在以四乙氧基硅烷(TOES)为基础的离子增强化学气相沉积(PlasmaEnhancedChemicalVaporDeposition,PECVD)的清洗制程中,利用分解效率高的C3F8气体取代C2F6气体。通过实验设计(DesignOfExperiment,DOE),调整腔体压力、射频(RF)功率、气体流量等参数,最终得到最优化的新清洗配方。应用到实际的量产中,有效地降低了成本,减少了PFC的排放。
简介:以短炭纤维、Si粉、炭粉和树脂为原料,通过均匀混合、温压成形,在1500℃原位反应最终制得C/C—SiC复合材料。测试试样的开孔隙率、热扩散率及摩擦磨损性能,研究制备工艺过程中后续炭化对摩擦磨损性能的影响,并对摩擦表面及磨屑进行扫描电镜观察和X射线衍射分析。结果表明:采用树脂浸渍炭化工艺制备的C/C—SiC制动材料具有适中的摩擦因数和较低的磨损率;经后续炭化,树脂转变为树脂炭,以磨粒的形式增大摩擦力,同时有效地降低了磨损率。
简介: C++Builder的VCL比VisualC++的MFC先进的另一个特性是异常处理,C++Builder可以编译VC程序还要多谢微软使用标准方法写MFC,但C++Builder仍不能使用为Delphi开发的VCL组件
简介:摘要目的探讨肝硬化合并肝癌及单纯肝癌患者不同child分级时补体C3、C4的表达意义。方法选取肝癌患者121例,健康对照组37例,均测定补体C3、C4含量。将肝癌患者分为肝硬化合并肝癌组及单纯肝癌组,并根据Child评分分级分组,比较两组间C3、C4水平的差异。结果1肝癌两组中随着Child分级由A级至C级变化血清补体C3水平逐渐降低,而补体C4水平则逐渐升高。2组间比较A级、B级时单纯肝癌组补体C3、C4水平均高于肝硬化合并肝癌组。单纯肝癌组与对照组比较差异同样有显著性。结论血清补体C3、C4与肝功能损伤严重程度相关,结合Child分级可更好地反映肝癌及肝硬化合并肝癌时肝脏储备功能及体液免疫水平,对临床诊治有重要意义。
简介:AbstractBackground:Aberrant activation of the complement system plays an important role in the pathogenesis and development of immunoglobulin A nephropathy (IgAN). The relationship between serum complement and the clinical-histopathological features and outcomes of IgAN is controversial. This retrospective study aimed to examine the relationship between the complement 3/4 (C3/C4) ratio and the clinicopathologic changes and prognosis of patients with IgAN.Methods:A total of 397 patients with primary IgAN from January 2007 to December 2012 at the Chinese People’s Liberation Army General Hospital were included in this study. The correlation test and Chi-square test or one-way analysis of variance test were performed to evaluate the relationship between the C3/C4 ratio and other clinical-pathological factors. Propensity score matching and a multivariate Cox regression model were used to calculate the risk factors of renal outcome.Results:The median follow-up period was 75 months. During the follow-up period, 62 patients (15.6%) developed into the end-stage renal disease (ESRD). The C3/C4 ratio at baseline was associated with the level of serum creatinine (SCr), 24 h urinary protein excretion (24 h Upre), global glomerular sclerosis, and tubulointerstitial lesion. The level of SCr and 24 h Upre and the degree of chronic kidney injury were statistically different among groups defined by different C3/C4 ratio levels. The survival rates of patients among groups with different C3/C4 ratio levels were different. After propensity score matching, eighty-eight pairs of patients were successfully matched, and the C3/C4 ratio was an influencing factor for the patients’ outcome (hazard ratio 0.587, 95% confidence interval 0.329-0.880). Patients with a C3/C4 ratio <3.6 had a poorer outcome compared with the others (P = 0.002).Conclusions:IgAN patients with decreased C3/C4 ratio displayed significantly more severe clinical symptoms and chronic renal injury than patients with higher ratios. A low C3/C4 ratio could be a risk factor for patients developing to ESRD.
简介:摘要: 火电厂在实际运行的过程中,最容易发生故障的类型就是电气设备故障,基于此,本篇文章主要对电气设备故障以及实际的故障处理方法进行深入的探究和分析。
简介:目的:观察小鼠不同程度缺氧适应对缺血缺氧脑即早基因c-fos和c-jun基因表达的影响。方法:采用链霉素亲生物素-过氧化酶(简称S-P)免疫组化技术。采用两种不同程度的缺氧预处理:①小鼠第一次缺氧开始到喘呼吸出现后,行第二次缺氧,定为B1组(此时瓶内的氧浓度为15%);②小鼠第一次缺氧开始到瓶内的氧浓度降低为10%后,行第二次缺氧,定为B2组。结果:B2组的低氧存活时间明显长于B1组;缺血缺氧后30minc-fos和c-jun基因阳性细胞呈低密度分布,1hc-fos基因表达下降,12h则基本消失,阳性细胞呈散在分布。c-jun基因的表达高峰在缺血缺氧3h、12h时,c-jun基因阳性细胞仍呈低密度分布;缺氧适应使缺血缺氧脑增加的c-fos基因的阳性细胞数减少,而使缺血缺氧脑增加的c-jun基因的阳性细胞进一步增加,B1组和B2组缺血缺氧脑基因表达的影响无差异,结论:缺血缺氧可诱发中枢神经系统c-fos、c-jun基因表达.且有时间依赖性;缺氧适应可抑制缺血缺氧脑c-fos基因的表达,增强缺血缺氧脑c-jun基因的表达。
简介:Tomeettheincreasingdemandforadvancedmaterialscapableofoperationover2000℃forfuturethermalprotectionsystemsapplication,C/C—ZrC—SiCcompositeswerefabricatedbyreactivemeltinfiltration(RMI)withZr,Simixedpowdersasrawmaterials.ThestructuralevolutionandformationmechanismoftheC/C—ZrC-SiCcompositeswerediscussed,andthemechanicalpropertyoftheas-preparedmaterialwasinvestigatedbycompressiontest.TheresultsshowedthataftertheRMIprocess,aspecialstructurewithZrC-SiCmulti-coatingasouterlayerandZrC-SiC-PyCceramicsasinnermatrixwasformed.ZrCandSiCrichareaswereformedinthecompositesandonthecoatingsurfaceduetotheformationofZr-SiintermetalliccompoundsintheRMIprocess.MechanicaltestsshowedthattheaveragecompressionstrengthoftheC/C-ZrC-SiCcompositeswas133.86MPa,andthecarbonfibersinthecompositeswerenotseriouslydamagedaftertheRMIprocess.