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壳牌煤气化常压输送阀故障处理及解决方案

阀门 2024年第2期 236-239页

作者：王兴寿郭以彬周兴样云南天安化工有限公司装备管理中心云南安宁650309

随着工业自动化水平的不断提高,壳牌煤气化常压输送阀在工业生产中的作用越来越重要。然而,由于阀门的复杂结构和长期运行,阀门故障在所难免。针对壳牌煤气化常压输送阀的故障处理及解决方案进行研究对比。介绍了壳牌煤气化常压输送阀... 详细信息

随着工业自动化水平的不断提高,壳牌煤气化常压输送阀在工业生产中的作用越来越重要。然而,由于阀门的复杂结构和长期运行,阀门故障在所难免。针对壳牌煤气化常压输送阀的故障处理及解决方案进行研究对比。介绍了壳牌煤气化常压输送阀的工作原理和故障率统计。技改后的安装示意图以及原来在线使用2台盘阀故障率高原因分析、应对措施,仍然存内部零件脱落的风险,在线使用1台夹板阀故障率低原因分析、夹板阀具有的一些属性、性能特点。提出了预防措施,以避免类似故障再次发生。通过实践运行情况,低磅级150 LB夹板阀在生产常压输送阀系列中取得良好的运用效果,夹板阀是解决常压输送的优先选择替代方案之一。最后,总结了壳牌煤气化常压输送阀故障处理及解决方案的实际成果,并提出了进一步的研究方向。

关键词：常压输送阀原因分析应对措施夹板阀替代方案

Preparation of Uniform Ni-B Amorphous Alloy Catalyst on CNTs and its Performance for Acetylene Selective Hydrogenation

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Chinese Chemical Letters 2006年第1期17卷 109-112页

作者： Chang Yuan HU Feng yi LI Rong bin ZHANG Li HUA Department of Chemistry Nanchang University Nanchang 330047

Uniform Ni-B amorphous alloys about 14 nm have been prepared on CNTs-A support,named Ni-B/CNTs-A. In comparison with the Ni-B/CNTs amorphous catalyst, Ni-B/CNTs-A showed higher nickel loading, determined by ICP and be... 详细信息

关键词： CNTs aniline Ni-B amorphous alloy catalyst acetylene selective hydrogenation.

基于机器学习算法建立非肝脏手术术后肝损伤风险预测模型

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陆军军医大学学报 2024年第7期46卷 760-767页

作者：孙义竹李雨捷梁浩刘祥黄家号舒欣宋艾璘杨智勇易斌陆军军医大学(第三军医大学)第一附属医院麻醉科重庆400038

目的基于术前及术中用药指标建立一个预测非肝脏手术患者术后肝损伤的机器学习预测模型。方法采用病例-对照研究设计方案,选择国内3家大型综合医院开发的数据库中2014年1月至2022年9月行非肝脏手术术后出现肝损伤患者315例,按阳性∶阴性... 详细信息

目的基于术前及术中用药指标建立一个预测非肝脏手术患者术后肝损伤的机器学习预测模型。方法采用病例-对照研究设计方案,选择国内3家大型综合医院开发的数据库中2014年1月至2022年9月行非肝脏手术术后出现肝损伤患者315例,按阳性∶阴性为1∶3的比例随机匹配同期非肝脏手术术后未发生肝损伤的928例病例作为阴性对照病例。将这1243例患者根据R语言设置的代码以7∶3的比例随机拆分为建模组(n=869)和验证组(n=374)。利用患者术前临床指标(基本信息、病史、相关评分表、手术相关信息和实验室检查)及术中用药情况基于k-近邻(k-nearest neighbor,KNN)、支持向量机(support vector machine linear,SVM)、逻辑回归(logistic regression,LR)、极端梯度提升(extreme gradient boosting,XGBoost)4种机器学习算法建立预测非肝脏手术术后肝损伤的模型,并在验证组通过受试者工作特征曲线(receiver operating characteristic,ROC)、精准-召回曲线(percision-recall curve,P-R)、临床决策分析曲线(decision curve analysis,DCA)、Kappa值、灵敏度、特异度、Brier分数、F 1分数对模型效能进行评估。结果4种机器学习算法建立的预测非肝脏手术术后肝损伤的模型以XGBoost算法最优,验证组中受试者工作特征曲线下面积(area under the receiver operating characteristic curve,AUROC)为0.916(95%CI:0.883~0.949),精准-召回曲线下面积(area under the precision-recall curve,AUPRC)为0.841,Brier评分0.097,灵敏度和特异度分别为78.95%和87.10%。结论基于XGBoost算法建立的非肝脏手术术后肝损伤预测模型对术后肝损伤的发生有良好的预测能力。

关键词：机器学习预测模型术后肝损伤

Application of principal component-radial basis function neural networks (PC-RBFNN) for the detection of water-adulterated bayberry juice by near-infrared spectroscopy

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第12期9卷 982-989页

作者： Li-juan XIE Xing-qian YE Dong-hong LIU yi-bin yiNG College of Biosystems Engineering and Food Science Zhejiang University Hangzhou 310029 China

Near-infrared (NIR) spectroscopy combined with chemometrics techniques was used to classify the pure bayberry juice and the one adulterated with 10% (w/w) and 20% (w/w) water. Principal component analysis (PCA) was applied to reduce the dimensions of spectral data, give information regarding a potential capability of separation of objects, and provide principal component (PC) scores for radial basis function neural networks (RBFNN). RBFNN was used to detect bayberry juice adulterant. Multiplicative scatter correction (MSC) and standard normal variate (SNV) transformation were used to preprocess spectra. The results demonstrate that PC-RBFNN with optimum parameters can separate pure bayberry juice samples from water-adulterated bayberry at a recognition rate of 97.62%, but cannot clearly detect water levels in the adulterated bayberry juice. We conclude that NIR technology can be successfully applied to detect water-adulterated bayberry juice.

关键词： Near-infrared (NIR) spectroscopy Principal component-radial basis function neural networks (PC-RBFNN) Bayberry juice Adulteration Chemometrics technique

Synthesis and characterization of CePO_4 nanowires via microemulsion method at room temperature

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Chinese Chemical Letters 2009年第7期20卷 857-860页

作者： yi bin yin Xin Shao Li Min Zhao Wen Zhi Li College of Materials Science and Engineering Liaocheng University Liaocheng 252059 China Renewable Energy & Eco-Materials Engineering Center Liaocheng University Liaocheng 252059 China

Uniform CeVO4 nanowires with diameter of about 25 nm were synthesized by the water-in-oil microemulsion method at room temperature from cerous chloride, sodium orthophosphate, sodium chloride, cyclohexane, Triton X-100 and cetyltrimethyl ammonium bromide （CTAB）. The crystal structure and morphology of the nanowires were characterized by XRD and TEM, respectively. The UV-vis absorption was detected by UV-vis spectrophotometer techniques. The results showed that as-prepared nanowires with the hexagonal phase have obvious quantum confinement effect and semiconductor characteristics. Little sodium chloride could play a positive role on the formation of CePO4 nanowires at room temperature. The size of the nanowires can be controlled through the joining of sodium chloride. C 2009 yi bin yin. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Nanowires Cerium phosphate Microemulsion Room temperature

梓醇对肝肺综合征大鼠肝肺损伤的保护作用研究

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陆军军医大学学报 2024年第6期46卷 587-596页

作者：曾子洋雷雨豪吴宪锋宋艾璘杨纯勇杨智勇李雨捷易斌陆军军医大学(第三军医大学)第一附属医院麻醉科重庆400038 重庆市中医院麻醉科重庆400021

目的探索梓醇通过增强TGR5表达和降低肝胆汁酸水平对胆总管结扎术(CBDL)大鼠肺损伤的保护作用。方法将大鼠随机分为三组[Sham组、CBDL组和梓醇(Catalpol)组],评估生存率、动脉血氧分压(PO2)和肺泡-动脉血氧分压差P(A-a)O2、肝功能、... 详细信息

目的探索梓醇通过增强TGR5表达和降低肝胆汁酸水平对胆总管结扎术(CBDL)大鼠肺损伤的保护作用。方法将大鼠随机分为三组[Sham组、CBDL组和梓醇(Catalpol)组],评估生存率、动脉血氧分压(PO2)和肺泡-动脉血氧分压差P(A-a)O2、肝功能、肝肺组织病理变化差异;进一步分析胆汁酸表达水平和TGR5的关系以及相关机制。结果梓醇治疗改善CBDL导致的肝功能损伤,提高CBDL的生存率和改善了低氧血症;减少了肝、肺血管新生。同时,梓醇通过增强TGR5和降低FXR的表达,减轻BAs水平过高引起肺损伤。结论梓醇通过上调TGR5和降低FXR的表达,改善BAs水平过高引起的肺损伤,发挥对CBDL大鼠的肝肺保护作用。

关键词：肝肺综合征(HPS) 梓醇 TGR5 BAs

The Modification on the Discreteness of Park-Ang Damage Index Based on Bayesian Methodology

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Journal of Harbin Institute of Technology(New Series) 2014年第1期21卷 102-108页

作者： yi-bin He Peng Deng Chao Zhang Pu-Sheng Shen College of Civil Engineering Hunan University

The discreteness is a common deficiency which impedes damage indices' practical application. It is caused by the arbitrary linear combination and some missing necessary variables. In order to deal with this problem,the correction term was added to the widely cited Park-Ang damage index. The unknown parameters in the correction term were obtained by the maximum likelihood estimation of these parameters' posterior distributions updated through Bayesian methodology. And the specimens for Bayesian updating were selected from PEER column database and Kawashima Earthquake Engineering Laboratory. Through model simplification process,a simplified modification was adopted,which has improved its goodness of fit to the experimental data. It has been found that the concrete core area and cross sectional area ratio,the longitudinal reinforcement ratio and the damage concentration factor are the critical variables affecting the error of the original damage index.

关键词： bayesian methodology damage index reinforced concrete seismic behavior

Electrochemical oxidation behavior of hydroxypivalaldehyde in the ionic liquids

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Chinese Chemical Letters 2008年第3期19卷 319-323页

作者： Jian Fang Zhong De Liang He Zhou Zhou yi bin Xu State Key Laboratory of Chemo/Biosensing and Chemometrics College of Chemistry and Chemical Engineering Hunan University Changsha 410082 China

The similar electrochemical oxidation behaviors of hydroxypivalaldehyde in ionic liquids （ILs） medium, C4MIMPF6, C4MIMBF4 and CsMIMPF6, are investigated using classic electrochemical methods, respectively. Only the product, hydroxypivalic acid is detected by high performance liquid chromatography （HPLC）. It can be conferred that the electrochemical oxidation of hydroxypivalaldehyde consists of two successive one-electron irreversible reactions at glass carbon （GC） electrode and the possible reaction mechanism in the ILs is proposed firstly. The diffusion coefficients of hydroxypivalaldehyde are obtained according to the electrochemical characteristics of hydroxypivalaldehyde in C4MIMPF6, C4MIMBF4 and CsMIMPF6.

关键词： Hydroxypivalaldehyde ILs Cyclic voltammetry Chronocoulometry

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黄芪甲苷脂质体原位凝胶眼部给药系统的研究

中南药学 2024年第7期22卷 1712-1717页

作者：吕菊芳于艺斌谢岩何鹏陈奋辽宁中医药大学药学院辽宁大连116600 辽宁中医药大学中医脏象理论及应用教育部重点实验室沈阳110847 中国医科大学沈阳110122

目的制备黄芪甲苷(ASⅣ)脂质体原位凝胶(ASⅣlips gel),对ASⅣlips gel进行制剂学表征及细胞学评价,探讨ASⅣlips gel在眼部给药系统的应用潜力。方法采用乙醇注入法制备黄芪甲苷脂质体(ASⅣlips),以包封率为考察指标进行ASⅣlips处方... 详细信息

目的制备黄芪甲苷(ASⅣ)脂质体原位凝胶(ASⅣlips gel),对ASⅣlips gel进行制剂学表征及细胞学评价,探讨ASⅣlips gel在眼部给药系统的应用潜力。方法采用乙醇注入法制备黄芪甲苷脂质体(ASⅣlips),以包封率为考察指标进行ASⅣlips处方及制备工艺优化,对最优处方及工艺制得的ASⅣlips进行表征;以壳聚糖(CS)和甘油磷酸钠(GP)为凝胶基质,通过物理交联制备CS/GP凝胶,对CS/GP凝胶进行表征;将ASⅣlips载入CS/GP凝胶构建ASⅣlips gel,并对ASⅣlips gel进行稳定性研究、体外释放研究、细胞毒性及细胞摄取考察。结果最优处方及工艺制得的ASⅣlips平均粒径为(75.09±0.65)nm,与透射电镜观察到的粒子大小接近,且粒径分布均匀;包封率可达71.68%,对ASⅣ具有较好的包载效率。红外光谱与X射线衍射分析可知已成功制得CS/GP凝胶;CS/GP凝胶在扫描电镜下呈明显的三维网状结构,35℃下胶凝时间为3 min。ASⅣlips gel连续7 d粒径基本无明显变化,稳定性良好;体外释放结果表明,与黄芪甲苷滴眼液相比,ASⅣlips gel有明显的缓释作用。细胞毒性结果显示ASⅣlips gel对人视网膜色素上皮细胞毒性较低,细胞相容性较好。分别用荧光显微镜定性观察、流式细胞仪定量分析制剂的细胞摄取情况,结果表明,脂质体原位凝胶制剂比滴眼液更易被人视网膜色素上皮细胞摄取。结论制备的ASⅣlips gel在眼部温度下可自发成胶,具有明显的缓释作用,更易被人视网膜色素上皮细胞摄取,有作为眼部给药系统的潜力。

关键词：黄芪甲苷脂质体原位凝胶