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71.
Microstructure and Friction Properties of CoCrFeMnNiTix High-Entropy Alloy Coating by Laser Cladding
Pengfei Liu Wudong Si Dabin Zhang Sichao Dai Benchi Jiang Da Shu Lulu Wu Chao Zhang Meisong Zhang 《Materials》2022,15(13)
To enhance the friction and wear properties of 40Cr steel’s surface, CoCrFeMnNi high-entropy alloy (HEA) coatings with various Ti contents were prepared using laser cladding. X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS) were used to characterize the phase composition, microstructure, and chemical composition of the samples. The findings demonstrated that the CoCrFeMnNiTix HEA coatings formed a single FCC phase. Fe2Ti, Ni3Ti, and Co2Ti intermetallic compounds were discovered in the coatings when the molar ratio of Ti content was greater than 0.5. The EDS findings indicated that Cr and Co/Ni/Ti were primarily enriched in the dendrite and interdendrite, respectively. Ti addition can effectively enhance the coating’s mechanical properties. The hardness test findings showed that when the molar ratio of Ti was 0.75, the coating’s microhardness was 511 HV0.5, which was 1.9 times the hardness of the 40Cr (256 HV0.5) substrate and 1.46 times the hardness of the CrCrFeMnNi HEA coating (348 HV0.5). The friction and wear findings demonstrated that the addition of Ti can substantially reduce the coating’s friction coefficient and wear rate. The coating’s wear resistance was the best when the molar ratio of Ti was 0.75, the friction coefficient was 0.296, and the wear amount was 0.001 g. SEM and 3D morphology test results demonstrated that the coating’s wear mechanism changed from adhesive wear and abrasive wear to fatigue wear and abrasive wear with the increase in Ti content. 相似文献
72.
基于成熟的脉诊、舌诊信息提取与识别的关键技术,集成便携式辅助诊疗系统突出脉诊、舌诊在中医诊疗中的重要作用,并融合其他四诊信息,实现自动辨证处方的临床辅助诊疗功能。便携式辅助诊疗系统体现了"四诊合参"的中医辨证诊断理念,其便携化、智能化、人性化的特点贴合临床实际,为脉诊、舌诊研究成果的推广应用奠定了完备的条件。 相似文献
73.
目的 采用多指标成分定量结合化学计量学方法对不同产地和不同采收期的桔梗Platycodon grandiflorum进行质量评价。方法 采用热浸法测定其醇溶性浸出物含量,应用超高效液相-电喷雾检测器(UPLC-CAD)法同时测定桔梗皂苷D、桔梗皂苷D3、去芹糖桔梗皂苷D、桔梗皂苷E、去芹糖桔梗皂苷E 5个活性成分含量,揭示不同采收期桔梗化学成分含量动态积累规律。运用主成分分析法分别对不同生长年限、不同产地桔梗进行综合评价,单因素方差分析比较不同产地桔梗各指标成分含量。结果 以春季4月、秋季9~10月、三年生为桔梗的最佳采收期。主成分分析、方差分析表明不同产地桔梗中指标含量存在显著性差异,同一产地不同批次间也有区别;根据主成分分析对不同产地桔梗进行综合评分,排名靠前的产地为甘肃陇南及河南省地区,陕西商洛、安徽亳州、内蒙古赤峰产地次之,山东淄博和山西太原产地排名较后。结论 以多指标成分定量结合化学计量学建立的评价方法明确了桔梗最佳采收期,评价了不同产地桔梗的质量,为桔梗药材质量控制研究提供依据。 相似文献
74.
Daoqin Liu Chengcheng Yang Ru Zhou Hongjing Zhao Tingwei Si Chunsheng Liu Qiwen Wu 《Journal of clinical laboratory analysis》2022,36(7)
ObjectivesThis study aimed to investigate the effect of hemoglobin (Hb) fluctuation after dialysis on the prognosis of cardiovascular‐related and all‐cause deaths in peritoneal dialysis (PD).MethodsAccording to the Hb fluctuation, patients were divided into low fluctuation group, moderate fluctuation group, and high fluctuation group, and then, the effects of Hb fluctuation after dialysis on the prognosis of cardiovascular‐related and all‐cause death in PD were analyzed by regression analysis.ResultsA total of 232 patients were selected in this study. Compared with the low Hb fluctuation group, the moderate and high fluctuation groups had lower body mass index (BMI), estimated glomerular filtration rate (eGFR), and baseline Hb, and the moderate fluctuation group had less erythropoietin (EPO) and dialysis dose. Compared with survivors, patients with cardiovascular‐related and all‐cause deaths had lower mean Hb and Hb fluctuation (all p < 0.05). Cox regression analysis showed that before and after adjusting for confounding factors, Hb fluctuation was still independently correlated with cardiovascular prognosis, and higher Hb fluctuation was still a protective factor for cardiovascular‐related death in the Hb‐substandard group, but there was no significant correlation between Hb fluctuation and all‐cause death. Multivariate linear regression analysis revealed that Hb fluctuation was positively correlated with Kt/V and EPO dosage, but negatively correlated with the baseline Hb.ConclusionHigh Hb fluctuation was a protective factor for cardiovascular‐related death in PD with substandard Hb. Compared with Hb fluctuation, correction of anemia timely and making Hb reaches the standard level had a greater impact on reducing cardiovascular‐related death in PD. 相似文献
75.
目的:探讨养阴抗毒胶囊及拆方对氢化可的松所致阴虚大鼠血清中氧化与抗氧化平衡的影响作用.方法:SD大鼠40只,随机分为对照组、阴虚模型组(YD)、养阴抗毒胶囊组(YC)和拆方抗毒组(大小蓟、槐花).大鼠在中药预处理及造模给药9 d后处死,以大鼠血清中皮质醇(CORT),超氧化物歧化酶(SOD)和丙二醛(MDA)含量为指标进行实验观察.结果:与对照组相比,YD组大鼠血清CORT,MDA含量分别为(9.10±1.70)μg/L,(27.16±8.54)Nu/mL,明显升高,SOD含量(520.75±126.87)μmol/L,明显降低,差异具有统计学意义(P<0.05);与YD组相比,YC组大鼠血清SOD含量(801.10±41.57)μmol/L,明显升高,(P<0.05),CORT,MDA含量分别为(6.01±2.11)μg/L,(10±1.40)μmol/L,明显降低,差异具有统计学意义(P<0.05);而拆方抗毒组无明显变化,差异无统计学意义(P>0.05),符合方剂的"整体取性"原理.结论:YC通过改变大鼠血清中SOD活性和降低MDA含量,对阴虚大鼠的抗氧化能力产生一定的影响. 相似文献
76.
BackgroundTraditional anthropometric measures, including body mass index (BMI), are insufficient for evaluating the risk of diabetes. This study aimed to evaluate the performance of new anthropometric measures and a combination of anthropometric measures for identifying diabetes.MethodsA total of 46 979 participants in the National Health and Nutrition Examination Survey program were included in this study. Anthropometric measures, including weight, BMI, waist circumference (WC), waist‐to‐height ratio (WtHR), conicity index (CI), and A Body Shape Index (ABSI), were calculated. Logistic regression analysis and restricted cubic splines were used to evaluate the association between the anthropometric indices and diabetes. The receiver operating characteristic (ROC) curve analysis was performed to compare the discrimination of different anthropometric measures.ResultsAll anthropometric measures were positively and independently associated with the risk of diabetes. After adjusting for covariates, the per SD increment in WC, WtHR, and CI increased the risk of diabetes by 81%, 83%, and 81%, respectively. In the ROC analysis, CI showed superior discriminative ability for diabetes (area under the curve 0.714), and its optimum cutoff value was 1.31. Results of the combined use of BMI and other anthropometric measures showed that among participants with BMI <30 kg/m2, an elevated level of another metric increased the risk of having diabetes (P < .001). Similarly, at low levels of weight, CI, and ABSI, an elevated BMI increased diabetes risk (P < .001).ConclusionsWtHR and CI had the best ability to identify diabetes when applied to the US noninstitutionalized population. Anthropometric measures containing WC information could improve the discrimination ability. 相似文献
77.
木犀草素促进囊性纤维化跨膜电导调节因子氯离子通道开放 总被引:1,自引:0,他引:1
目的:研究木犀草素对依赖于3,5-环腺苷酸(cAMP)的囊性纤维化跨膜电导调节因子(CFTR)Cl^-通道的激活作用。方法:利用稳定共表达人CFTR与一种对卤族元素敏感的荧光绿蛋白突变体(EYFP-H148Q)的Fischer大鼠甲状腺(FRT)细胞模型,测定木犀草素对CFTR介导的I^-内流速度。结果:木犀草素能够以剂量依赖的方式激活CFTR的I^-转运,其对CFTR Cl^-通道的激活效应具有作用迅速、可逆的特点。木犀草素在发挥激活作用时依赖于腺苷环化酶激动剂Forskolin的存在,其单独与细胞孵育不提高细胞内cAMP的水平。结论:发现了木犀草素能够以剂量依赖方式激活CFTR,并且初步确定了木犀草素通过直接与CFTR结合发挥作用。 相似文献
78.
目的观察不用时间点暴露于不同剂量醋酸铅后大鼠神经胶质瘤C6细胞葡萄糖调节蛋白78(glucoseregulated protein 78,GRP78)表达量的影响,探讨不同时间不同剂量铅暴露对内质网应激反应的影响。方法Wistar大鼠神经胶质瘤C6细胞培养于含醋酸铅的培养液中,分别于不同时间终止染铅,用Western印迹法检测内质网GRP78表达量。结果(1)0.2μmol/L染铅组:7和30 d GRP78蛋白表达显著增高,其余各个时间点均无显著性变化;(2)1.0μmol/L染铅组:1 d后GRP78蛋白表达量开始显著增高,染铅30 d时已达到染铅前的6.3倍;(3)2.0μmol/L染铅组:0.5 h起GRP78表达量即显著增高,染铅7 d时达到高峰,是染铅前的4.3倍,到30 d时表达量又下降为染铅前的2.6倍。结论铅可以使Wistar大鼠神经胶质瘤细胞内质网上的GRP78蛋白应激性表达增加,内质网上的GRP78是铅的重要蓄积库。 相似文献
79.
傅里叶变换红外光谱技术鉴别4种中药材的不同来源 总被引:1,自引:0,他引:1
目的:对矮地茶、大黄、黄芩、夏枯草4种中药材不同批次样品的来源进行鉴别。方法:采用傅里叶变换红外光谱(FTIR)技术获得4种中药材各个批次样品的红外光谱图和高分辨的二阶导数谱,并对其进行分析。结果:每种不同来源的中药材即产地不同的野生品与栽培品均具有不同的红外光谱特征,其红外吸收峰峰位与相对强度均存在一定差异;并且二阶导数谱更加突出了红外光谱的特征性。结论:本方法快速、简单、特征性强,可以对中药材不同批次样品的来源进行鉴别。 相似文献
80.
目的 研究乌鲁木齐地区非综合征性聋患者线粒体12S rRNA基因突变情况。方法 收集乌鲁木齐非综合征性聋患者标本609例,对其进行临床和分子遗传学评估。结果 12S rRNA基因突变分析共发现11个突变位点,已知的A1555G、961DelT、C1494T突变分别占2.96%,1.15%,0.16%。另外A1047G突变相关报道较少,A1585G突变未见相关报道。其他突变均为多态性位点。结论 线粒体12S rRNA突变是引起遗传性聋的重要因素,此次乌鲁木齐地区线粒体12S rRNA A1555G突变在聋病人群中的检出率与前期报道相比有所降低,可能与耳毒性药物使用量降低有关。A1047G与新发现的A1585G突变是否与聋相关,还需进一步研究。对筛查中阳性突变携带者及其母系家庭成员需告知氨基糖苷类抗生素使用风险,使其避免使用,逐步降低药物性聋的发生率。 相似文献