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黄精霉变过程中麦角甾醇变化规律及基于电子鼻技术的快速预测模型研究

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中国现代中药 2024年第8期26卷 1337-1344页

作者：拱健婷于淑琳徐媛媛赵艺萌关佳莉丛悦梁如李莉邹慧琴首都医科大学附属北京中医医院北京市中医药研究所北京100010 北京中医药大学中药学院北京102488

目的:麦角甾醇是霉变相关的重要指标之一,探索建立一种麦角甾醇快速检测方法。方法:采用人工模拟培养获取不同霉变程度的黄精样品;采用传统性状鉴定法开展黄精外观性状的观察、鉴定与分类;使用超高效液相色谱法进行麦角甾醇含量测定;通... 详细信息

目的:麦角甾醇是霉变相关的重要指标之一,探索建立一种麦角甾醇快速检测方法。方法:采用人工模拟培养获取不同霉变程度的黄精样品;采用传统性状鉴定法开展黄精外观性状的观察、鉴定与分类;使用超高效液相色谱法进行麦角甾醇含量测定;通过电子鼻技术实现黄精气味的数字化检测。结果:共制备得到35份不同霉变程度的黄精样品;感官评价将黄精样品分为未霉变、轻微霉变和严重霉变3个阶段;35份黄精样品中麦角甾醇质量分数为0~90.4356 mg·kg^(–1),随着黄精霉变程度增加而上升;电子鼻的18根传感器中,S1~S16均表现出随着黄精霉变程度加深其最大响应值的绝对值降低,S18则相反,其最大响应值随着黄精霉变程度增加而升高。相关性分析显示,麦角甾醇含量与S1、S7~S16响应值呈极显著负相关,与S2~S6、S17、S18响应值呈极显著正相关,并且建立了回归方程Y=67.577–78.453X(r=0.634),其中Y为麦角甾醇含量、X为传感器PA/2最大响应值。结论:黄精的气味与其内在的化学成分麦角甾醇密切相关,电子鼻技术联合回归分析能为初步预测黄精中麦角甾醇的含量提供一种可行、有效的方法。

关键词：黄精电子鼻麦角甾醇霉变回归分析

无气相氧条件下La_(0.8)Sr_(0.2)Fe_(0.9)Co_(0.1)O_3钙钛矿氧化物的氧物种直接氧化甲烷

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催化学报 2008年第10期29卷 954-956页

作者：代小平余长春吴琼中国石油大学(北京)CNPC催化重点实验室北京102249

以La0.8Sr0.2Fe0.9Co0.1O3钙钛矿氧化物作氧载体,采用连续流动反应和连续顺序Redox反应考察了氧物种氧化甲烷的反应性能.结果表明,连续流动反应中La0.8Sr0.2Fe0.9Co0.1O3氧化物的氧物种能选择氧化甲烷生成合成气.在适宜的再氧化条件下,... 详细信息

以La0.8Sr0.2Fe0.9Co0.1O3钙钛矿氧化物作氧载体,采用连续流动反应和连续顺序Redox反应考察了氧物种氧化甲烷的反应性能.结果表明,连续流动反应中La0.8Sr0.2Fe0.9Co0.1O3氧化物的氧物种能选择氧化甲烷生成合成气.在适宜的再氧化条件下,通过连续顺序Redox反应实现了La0.8Sr0.2Fe0.9Co0.1O3氧化物的氧物种氧化甲烷连续生成合成气,消耗的氧物种可通过与气相氧反应而得到补充.但随着Redox反应的进行,氧化物的持续供氧性能下降,钙钛矿结构被破坏.

关键词： La0.8Sr0.2Fe0.9Co0.1O3 钙钛矿氧载体甲烷合成气氧化还原反应

Quasi-two-body B_((s))→K^(*)γ→Kπγ decays in the perturbative QCD approach

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Chinese Physics C 2022年第12期46卷 126-134页

作者： Zhi-Qing Zhang Yan-Chao Zhao Zhi-Lin guan Zhi-Jie Sun Zi-yu Zhang Ke-Yi He department of Physics Henan University of TechnologyZhengzhou 450052China

In this study,we investigate quasi-two-body B_((s))→K^(*)γ→Kπγ decays in the perturbative QCD ***-meson distribution amplitudes are introduced to describe the final state interactions of the Kπpair,which involve time-like form factors and Gegenbauer *** calculate the CP averaged branching ratios of the B_((s))→K^(*)γ→Kπγ *** results are in agreement with newly updated data measured by Belle Ⅱ.This suggests that it is more appropriate to analyze these quasi-two-body B decays in the three-body framework than the two-body *** also predict direct CP asymmetries for the considered decay modes and find that A_CP(B_(u,d)→K^(*)γ→Kπγ) is small and less than 1% in magnitude,whereas A_CP(B_(s)→K^(*)γ→Kπγ)is larger and can reach a few *** predictions can be tested in future B meson experiments.

关键词： B meson decay perturbative QCD three-body radiative decay

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探地雷达及EH4对钼矿采空区的综合探测

地球物理学进展 2010年第5期25卷 1763-1768页

作者：戴前伟余凯冯德山张彬中南大学信息物理工程学院长沙410083

采空区严重威胁着地面建筑物和矿山的安全,对采空区探测方法的研究有着重大的现实意义.本文探讨了探地雷达及EH-4电导率成像法对某露天钼矿采空区探测的方法技术及其应用效果.探地雷达对浅层地段不仅有很高的探测精度和高分辨率,能达到... 详细信息

采空区严重威胁着地面建筑物和矿山的安全,对采空区探测方法的研究有着重大的现实意义.本文探讨了探地雷达及EH-4电导率成像法对某露天钼矿采空区探测的方法技术及其应用效果.探地雷达对浅层地段不仅有很高的探测精度和高分辨率,能达到对浅部采空区的精确定位.EH-4电导率成像系统的探测深度大,通过电阻率断面图的局部异常体,可以直观的来判断采空区的位置从而查明深部采空区,结合二者对采空区进行综合探测.

关键词：采空区探地雷达 EH-4

Effects of Al on Microstructure and High-Temperature Wear Properties of Austenitic Heat-Resistant Steel

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Journal of Iron and Steel Research International 2012年第3期19卷 62-66页

作者： ZHANG Yan1, SUN yu-fu2, ZHAO Jing-yu2, guan Shao-kang2 (1. School of Materials Engineering, Nanjing Institute of Technology, Nanjing 211167, Jiangsu, China 2. School of Materials Science and Engineering, Zhengzhou University, Zhengzhou 450002, Henan, China) [a] School of Materials Engineering Nanjing Institute of Technology Nanjing 211167 Jiangsu China [b] School of Materials Science and Engineering Zhengzhou University Zhengzhou 450002 Henan China

Microstructure and high-temperature dry sliding wear at 600 ~C in ambient air of austenitic heat-resistant steel ZG40Cr25Ni20 with different contents （mass percent） of AI （0 to 7.10~） have been investigated. The results show that microstructures of 4.68% and 7.10% A1 addition content consist of the matrix and reinforcement of inter- metallic compound y＇ and carbide, while microstructures of ZG40Cr25Ni20 without A1 and with A1 of 1.68% are ab- sent of y＇. Higher wear resistance than the original ZG40Cr25Ni20 alloy is achieved in alloys with higher content of A1 under the same high-temperature wear test condition. The wear rates of Fe-25Cr-20Ni-7.10A1 and Fe-25Cr-20Ni- 4.68A1 are only 20.83% and 45.83% of that of Fe-25Cr-20Ni, respectively. Heat-resistant steels with higher con- tents of AI （4.72% and 7.10%） have higher hardness than those with lower contents of AI （1.68% and 0）. Wear mechanisms of ZG40Cr25Ni20 are considered as severe plough plastic deformation and slight adhesive. However, wear mechanisms of Fe-25Cr-20Ni 4.68A1 are light micro-cutting and oxidation-wear, while that of Fe-25Cr-20Ni- 7. 10A1 are severe adhesive transfer and oxidation-wear_

关键词： austenitic heat resistant steel Al microstructure high-temperature sliding wear mechanism

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储层岩石时间域激发极化效应的数学模拟

计算物理 2012年第3期29卷 354-360页

作者：关继腾于华王谦范业活程媛媛中国石油大学(华东)理学院山东青岛266555

以储层岩石的串联毛管模型为基础,建立描述含水储层岩石时间域激发极化效应的数学模型.数值模拟储层岩石孔隙中离子的浓差极化效应和双电层形变效应.孔隙中浓差极化控制着激发极化随时间的变化,双电层形变不控制激发极化随时间的变化.... 详细信息

以储层岩石的串联毛管模型为基础,建立描述含水储层岩石时间域激发极化效应的数学模型.数值模拟储层岩石孔隙中离子的浓差极化效应和双电层形变效应.孔隙中浓差极化控制着激发极化随时间的变化,双电层形变不控制激发极化随时间的变化.浓差极化效应对激发极化极化率的贡献较小,双电层形变效应对激发极化极化率的贡献较大.激发极化充放电过程的快慢,主要取决于固液界面阳离子的吸附能力和岩石的孔隙结构.

关键词：储层岩石激发极化毛管模型数学模型数值模拟

Complications of endoscopic retrograde cholangiography in the post-MRCP era: A tertiary center experience

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World Journal of Gastroenterology 2005年第33期11卷 5209-5212页

作者： Tze-Zen Ong Jen-Lock Khor dede-Sutedja Selamat Khay-guan Yeoh Khek-yu Ho department of Gastroenterology and Hepatology National University Hospital Singapore

AZM： To evaluate our experience in endoscopic retrograde cholangio-pancreatography （ERCP） in terms of fulfilling the ASGE guidelines in indications, positive findings, and complications in the post-magnetic resonance cholangiopancreatography （MRCP） era. METHODS： Between November 2001 and February 2003, consecutive ERCP cases were prospectively evaluated with regard to the indications, findings, cannulation techniques, devices used during the procedure, sedation given, duration of procedure, and complications. These data were entered in a database for subsequent processing and analysis. RESULTS： Of 336 cases, 21.4% were diagnostic and 78.6% therapeutic ERCR The indications for ERCP fulfilled the ASGE guidelines in 323 cases （96.1%）. Suspected bile duct stone was the most frequent indication （26.8%）, and this was followed by cholangitis （24.4%）, dilated common bile duct （14.9%）, and cholestatic jaundice （23.4%）. Cannulation success rate was 94%. Biliary sphincterotomy was performed in 175 （52.1%） patients. Repeated ERCP was performed on 31.5% of the patients. Overall, the complication rate was 9.8% with 0.3% being procedurerelated mortality. The complications were pancreatitis （5.4%）, bleeding （0.8%）, cholangitis （2.4%） and others （1.5%）. No significant difference was observed between the complication rate and the type of ERCP performed. CONCLUSION： Our study showed that post-ERCP complication rate was comparable with the other large prospective studies and there was no difference in the complication between the diagnostic and therapeutic ERCP.

关键词： Endoscopic retrograde cholangiopancreatogram Complication Pancreatitis

Formation of unusual Cr^5+charge state in CaCr0.5Fe0.5O3 perovskite

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Chinese Physics B 2018年第3期27卷 433-438页

作者： Jian-Hong dai Qing Zhao Qian Sun Shuo Zhang Xiao wang Xu-Dong Shen Zhe-Hong Liu Xi Shen Ri-Cheng yu Ting-Shan Chan Lun-Xiong Li guang-Hui Zhou Yi-feng Yang Chang-Qing Jin You-Wen Long Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China School of Physics University of Chinese Academy of SciencesBeijing 100049China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201203China "National"Synchrotron Radiation Research Center 101 Hsin-Ann RoadHsinchu 30076TaiwanChina Institute for Brain Research and Rehabilitation South China Normal UniversityGuangzhou 510631China department of Physics and Synergetic Innovation Center for Quantum Effects and Applications of Hunan Hunan Normal UniversityChangsha 410081China

A new oxide CaCr0.5Fe0.5O3 was prepared under high pressure and temperature conditions. It crystallizes in a B-site disordered Pbnm perovskite structure. The charge combination is determined to be Cr^5＋/Fe^3＋ with the presence of unusual Cr^5＋ state in octahedral coordination, although Cr^4＋ and Fe^4＋ occur in the related perovskites CaCrO3 and CaFeO3. The randomly distributed Cr^5＋ and Fe^3＋ spins lead to short-range ferromagnetic coupling, whereas an antiferromagnetic phase transition takes place near 50 K due to the Fe^3＋-O-Fe^3＋ interaction. In spite of the B-site Cr^5＋/Fe^3＋ disorder, the compound exhibits electrical insulating behavior. First-principles calculations further demonstrate the formation of CaCr0.5^5＋Fe0.5O3 charge combination, and the electron correlation effect of Fe^3＋ plays an important role for the insulting ground state. CaCr0.5Fe0.5O3 provides the first Cr^5＋ perovskite system with octahedral coordination, opening a new avenue to explore novel transition-metal oxides with exotic charge states.

关键词： high pressure synthesis perovskite valence state

活塞环表面处理对船舶主机缸套/活塞环摩擦学特性的影响

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大连水产学院学报 2005年第1期20卷 77-80页

作者：韩德宝于功志关德林大连海事大学轮机工程学院辽宁大连116026 大连水产学院机械工程学院辽宁大连116023

在使用普通CD40润滑油润滑的条件下, 以磨损失重、表面粗糙度和摩擦系数为状态参量, 采用表面渗氮和表面喷涂技术对活塞环进行处理, 将处理后的活塞环对气缸套 /活塞环摩擦磨损特性的影响进行了模拟试验研究, 并与实际使用的活塞环的试... 详细信息

在使用普通CD40润滑油润滑的条件下, 以磨损失重、表面粗糙度和摩擦系数为状态参量, 采用表面渗氮和表面喷涂技术对活塞环进行处理, 将处理后的活塞环对气缸套 /活塞环摩擦磨损特性的影响进行了模拟试验研究, 并与实际使用的活塞环的试验结果进行了比较。结果表明, 表面经渗氮处理的活塞环的摩擦学性能最优。

关键词：汽缸套活塞环表面处理摩擦磨损失重