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氧分子和苯酚自由基反应机理的理论研究

原子与分子物理学报 2007年第1期24卷 1-6页

作者：黄明强张为俊王振亚郝立庆赵文武李劲松高晓明中国科学研究院安徽光学精密机械研究所环境光谱学实验室合肥230031

用密度泛函理论B3LYP方法对氧分子和苯酚自由基反应机理进行了研究.在B3LYP/6-31G(d,p)水平上优化得到了反应路径上的反应物、中间体、过渡态和产物的几何构型和谐振频率;并在B3LYP/6-311++G(2df,2pd)水平上进行了单点能计算.计算结果表... 详细信息

用密度泛函理论B3LYP方法对氧分子和苯酚自由基反应机理进行了研究.在B3LYP/6-31G(d,p)水平上优化得到了反应路径上的反应物、中间体、过渡态和产物的几何构型和谐振频率;并在B3LYP/6-311++G(2df,2pd)水平上进行了单点能计算.计算结果表明,苯酚是O2同苯酚自由基Ⅰ反应的主要产物,苯酚过氧自由基Ⅴ和Ⅵ是此反应的次要产物.苯酚过氧自由基Ⅴ的主要后继反应中,环化形成[3.2.1]双环氧桥自由基Ⅶ是主要的反应路径,Ⅶ可以进一步开环反应,形成环裂解产物1,2和1,4二醛.

关键词：氧分子苯酚自由基密度泛函理论反应机理过渡态

Inversion-based attenuation compensation with dip constraint

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Petroleum Science 2022年第2期19卷 543-553页

作者： Xiong Ma li-li Huo Guo-Fa li hao li qing-Long Meng School of Geophysics China University of Petroleum-BeijingState Key Lab of Petroleum Resources and ProspectingKey Lab of Geophysical Exploration of CNPCChangping102249BeijingChina Exploration and Development Research Institute Jidong OilfieldChina National Petroleum CorporationTangshanHebei 063000China Exploration and Development Research Institute Dagang OilfieldChina National Petroleum CorporationTianjin300280China

Instability is an inherent problem with the attenuation compensation methods and has been partially relieved by using the inverse ***,the conventional inversion-based attenuation compensation approaches ignore the important prior information of the seismic ***,the compensated result appears to be distorted spatial continuity and has a low signal-to-noise ratio(S/N).To alleviate this issue,we have incorporated the seismic dip information into the inversion framework and have developed a dip-constrained attenuation compensation(DCAC)*** seismic dip information,calculated from the poststack seismic data,is the key to construct a dip constraint *** from the introduction of the seismic dip constraint,the DCAC approach maintains the numerical stability and preserves the spatial continuity of the compensated *** and field data examples demonstrate that the proposed method can not only improve seismic resolution,but also protect the continuity of seismic data.

关键词： Attenuation compensation Instability Inverse scheme Seismic dip Seismic resolution Spatial continuity

Integrating lipidomics and gut microbiota to study the anti-hyperlipidemia effect of Sargentodoxae Caulis extract

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Traditional Medicine Research 2025年第1期10卷 1-11页

作者： Xiao-Xiao Zhang li Jia Xiu-Jun Zhan Charity Ngina qing-Rui Zhang Xiao-Ge li Qi-Bao Jiang Shi Bai Miao-Miao Jiang National Key Laboratory of Chinese Medicine Modernization Tianjin University of Traditional Chinese MedicineTianjin 301617China Haihe Laboratory of Modern Chinese Medicine Tianjin 301617China School of Medicine Taizhou UniversityTaizhou 318000China.

Background:Sargentodoxae Caulis(SC)is the vine stem of Sargentodoxa Cuneata(Oliv.)Rehd.&*** in ***,and it in traditional Chinese medicine has been known for promoting blood circulation and removing blood stasis as recorded in the ancient book“Illustrated Classics of Materia Medica”.It has been used effectively to treat blood stasis too in modern clinical ***,the anti-hyperlipidemia effect of SC is not fully *** paper aims at exploring the use of SC stems to improve the balance of blood lipids in the body,and its new role in treating ***:The effects of SC extract on hyperlipidemia were explored by combining lipidomics and gut ***,we explored the potential mechanism of SC in treating hyperlipidemia by pathway ***:The results showed that the stem extract of SC could restore the physiological and biochemical indices of hyperlipidemia in mice,as well as repair the morphological and structural damage to *** to the Model group,the SC extract significantly reduced the liver index,epididymal fat index,and Lee’s *** also significantly decreased serum levels of total cholesterol,triglycerides,low-density lipoprotein cholesterol,peroxisome proliferator-activated receptor gamma(PPAR-γ),D-lactate,and free fatty acids,while significantly increasing the relative content of peroxisome proliferator-activated receptor alpha(PPAR-α).These changes were statistically ***-targeted lipidomics,based on LC-MS,were utilized to investigate the lipid metabolism characteristics in serum,liver,and epididymal fat of the *** was observed that,compared to the blank group,the Model group exhibited significant changes primarily in glycerol lipids and *** treatment group also displayed alterations in these lipids.A total of 38,81,and 27 differential lipids were identified in serum,liver,and epididymal fat samples,*** these,14 common differenti

关键词： hyperlipidemia Sargentodoxae Caulis lipidomics intestinal flora

8-异前列腺素和丙二醛与老年患者术后认知功能障碍的探讨

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中国医药导刊 2016年第11期18卷 1085-1086页

作者：杨明媛程庆好李蕾王佳婉岳云煤炭总医院麻醉科北京100028 北京朝阳医院麻醉科北京100020

目的:探讨尿排泄率8-异前列腺素(U8-iso PG)与肌酐(Cr)的比值(U8-iso PG:Cr)和丙二醛(UMDA)与Cr的比值(UMDA:Cr)与老年患者术后认知功能障碍(POCD)的相关性。方法:72例>65岁老年患者分别于手术前,手术后1周接受认知测试调查,通过"Z"评... 详细信息

目的:探讨尿排泄率8-异前列腺素(U8-iso PG)与肌酐(Cr)的比值(U8-iso PG:Cr)和丙二醛(UMDA)与Cr的比值(UMDA:Cr)与老年患者术后认知功能障碍(POCD)的相关性。方法:72例>65岁老年患者分别于手术前,手术后1周接受认知测试调查,通过"Z"评分确定认知功能障碍组(POCD组,21例)和非POCD组(对照组,51例)。分别于术前、术后1、2和7天收集晨尿。U8-isoPG采用酶联免疫吸附法(EliSA法),UMDA采用测定分光光度检测,并检测Cr浓度。结果:⑴手术后第7天POCD组的U8-iso PG:Cr高于对照组,与手术前相比升高的值也高于对照组(P0.05);两组间比较差异没有统计学意义(P>0.05)。结论:尿U8-isoPG是一个有价值的检测脂质过氧化标记物,可能与老年患者术后POCD有关;尿丙二醛没有参与早期POCD的发病机制。

关键词：氧化应激认知功能障碍丙二醛 8-异前列腺素肌酐

Research on Two-stage Voltage and Reactive Power Optimization Coordinated Control Method Considering Flexible On-load Tap Changer

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Dianwang Jishu/Power System Technology 2025年第1期49卷 272-283页

作者： li, Jiaming Huo, Qunhai Yin, Jingyuan Lu, hao Zhou, Jing Zhu, Meisheng He, Wei Dong, Hongwei Institute of Electrical Engineering Chinese Academy of Sciences Haidian District Beijing 100192 China School of Electronic Electrical and Communication Engineering University of Chinese Academy of Sciences Shijingshan District Beijing 100049 China Shanghai Jiguang Polytechnic College Baoshan District Shanghai 201901 China Three Gorges Electric Power Co. Ltd. Hubei Province Wuhan 430000 China

With the large-scale integration of distributed photovoltaic (DPV) in the distribution network, voltage exceeding limits and fluctuations are becoming increasingly severe. The voltage and reactive power optimization and coordination control method considering new power quality management devices needs to be further improved to adapt to the new changes in the power grid. This article considers the power quality regulation effect of the new flexible on-load tap changer (OLTC) and proposes a two-stage voltage and reactive power optimization coordinated control method. The first stage is the day before hour level scheduling stage. Based on distributed photovoltaic and load prediction data, the active output results of DPV and the switching results of flexible OLTC taps and capacitor banks are obtained through power flow calculation and iterative optimization. The second stage is the minute-level reactive power optimization stage. Based on the first stage, considering the reactive power output characteristics of flexible OLTC and DPV, adjusting the reactive power output of the equipment while correcting the capacitor bank switching combination in the first stage, further reducing the maximum voltage deviation of each node and making the distribution network voltage distribution more reasonable. An IEEE33 node distribution system simulation model is built in the paper. The proposed two-stage voltage and reactive power optimization coordination control method considering flexible OLTC can improve the DPV absorption level by 9.29% based on the conventional economic optimal goal of 88.07%, while meeting the requirement that the voltage deviation of the entire node is less than 0.1pu During the entire period, the overall economic efficiency improved by 7.8%. The results demonstrate the rationality and effectiveness of the proposed method. © 2025 Power System Technology Press. All rights reserved.

关键词： Quality management

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乙苯光电离的实验研究

高等学校化学学报 2010年第10期31卷 2063-2066页

作者：陶玲黄明强郝立庆张为俊王振亚孔蕊弘单晓斌刘付轶盛六四中国科学院安徽光学精密机械研究所环境光谱学实验室合肥230031 中国科学院大气成分与光学中国科学院重点实验室合肥230031 厦门大学嘉庚学院环境科学与工程系漳州363100 中国科学技术大学国家同步辐射实验室合肥230026

利用真空紫外同步辐射和反射式飞行时间质谱研究了乙苯分子的光电离,通过测量母体分子的光电离质谱(PIMS)以及母体离子和主要碎片离子的光电离效率曲线(PIEs),确定了乙苯分子的电离能IE(C8H1+0)=(8.66±0.02)eV,主要碎片离子C7H7+和C6H6... 详细信息

利用真空紫外同步辐射和反射式飞行时间质谱研究了乙苯分子的光电离,通过测量母体分子的光电离质谱(PIMS)以及母体离子和主要碎片离子的光电离效率曲线(PIEs),确定了乙苯分子的电离能IE(C8H1+0)=(8.66±0.02)eV,主要碎片离子C7H7+和C6H6+的出现能分别为(10.81±0.02)和(10.99±0.02)eV;利用经验公式计算出产生碎片离子C7H7+和C6H6+需要的解离能(Ed)分别为(2.15±0.04)和(2.33±0.04)eV.结合相关的热化学参数,推算出C8H1+0,C7H7+和C6H6+的标准生成焓分别为865.5,927.2和1037.9kJ/mol.为进一步研究乙苯的大气光氧化反应机理提供了参考.

关键词：乙苯同步辐射光电离碎片离子

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五氟乙烷的真空紫外光电离光解离

物理化学学报 2005年第5期21卷 539-543页

作者：杨斌黄超群杨锐卫立夏王晶王思胜单晓斌齐飞张允武盛六四王振亚郝立庆周士康中国科学技术大学国家同步辐射实验室合肥230029 中国科学院安徽光学精密机械研究所环境光谱学实验室合肥230031

利用同步辐射真空紫外光电离结合飞行时间质谱对五氟乙烷(CHF2CF3)进行了光电离光解离的研究,测定了CHF2CF3的电离势及该分子主要碎片离子的出现势.结果表明:CHF2CF3的绝热电离势为(12.25±0.10)eV,主要碎片离子有CF2CF3+、CHFCF3+、CF2... 详细信息

利用同步辐射真空紫外光电离结合飞行时间质谱对五氟乙烷(CHF2CF3)进行了光电离光解离的研究,测定了CHF2CF3的电离势及该分子主要碎片离子的出现势.结果表明:CHF2CF3的绝热电离势为(12.25±0.10)eV,主要碎片离子有CF2CF3+、CHFCF3+、CF2CF2+、CF3+、CHF2+、CHF+和CF+,其出现势分别为(13.93±0.10)eV,(15.25±0.10)eV,(15.12±0.10)eV,(13.30±0.05)eV,(13.05±0.08)eV,(19.17±0.10)eV和(19.56±0.15)eV.另外,用从头算分子轨道理论计算了解离电离过程中所有碎片的总能量,并给出了电子态及对称性.根据实验结果和理论计算,分析了可能的解离通道,并得到了分子及母体离子的键解离能等重要的热力学数据.

关键词：五氟乙烷光电离出现势解离能

Geochronology and Geochemistry of the Xingxingxia Triassic A-type Granites in Central Tianshan,NW China:Petrogenesis and Tectonic Implications

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Acta Geologica Sinica(English Edition) 2024年第2期98卷 337-351页

作者： HUANG Zengbao li Xiyao Zhao hao LU qing Geological Survey of Gansu Province Lanzhou 735000China Key Laboratory of Submarine Geosciences and Prospecting Techniques MOE and College of Marine GeosciencesOcean University of ChinaQingdaoShandong 266100China Research Institute of Petroleum Exploration and Development Shengli OilfieldSINOPECDongyingShandong 257000China

The Triassic granitoids in Central Tianshan play a key role in determining the petrogenesis and tectonic evolution on the southern margin of the Central Asian orogenic *** this study,we present SHRIMP zircon U-Pb ages,Hf isotopic and geochemical data on the Xingxingxia biotite granite,amazonite granite and granitic pegmatite in Central Tianshan,NW *** U-Pb dating yielded formation ages of 242 Ma for the biotite granite and 240 Ma for the amazonite *** granitoid rocks have high K_(2)O with low MgO and CaO *** are enriched in Nb,Ta,Hf and Y,while being depleted in Ba and Sr,showing flat HREE patterns and negative Eu *** have typical A-type granite geochemical signatures with high Ga/A_(1)(8–13)and TFeO/(TFeO+MgO)ratios,showing an A_(2) affinity for biotite granite and an A_(1) affinity for amazonite granite and granitic *** ε_(Hf)(t)values of the granitoids are 0.45–2.66,with Hf model ages of 0.99–1.17 *** suggests that these A-type granites originated from partial melting of the lower *** propose that Xingxingxia Triassic A-type granites formed under lithospheric extension from post-orogenic to anorogenic intraplate settings and NE-trending regional strike-slip fault-controlled magma emplacement in the upper crust.

关键词： Triassic A-type granite Xingxingxia Central Tianshan Central Asian orogenic belt

Study on the fusion emotion classification of multiple characteristics based on attention mechanism

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High Technology Letters 2021年第3期27卷 320-328页

作者： li Ying Shao qing hao Weichen School of Optoelectronic Information and Intelligent Engineering University of Shanghai for Science and TechnologyShanghai 200093P.R.China

The current research on emotional classification uses many methods that combine the attention mechanism with neural ***,the effect is unsatisfactory when dealing with complex *** emotional classification model is proposed,which combines multi-head attention(MHA)with improved structured-self attention(SSA).The model makes several different linear transformations of input by introducing MHA mechanism and can extract more comprehensive high-level phrase representation features from the word embedded ***,it can realize the parallelization calculation and ensure the training speed of the *** improved SSA structure uses matrices to represent different parts of a sentence to extract local key information,to ensure that the degree of dependence between words is not affected by time and sentence length,and generate the overall semantics of the *** results show that the current model effectively obtains global structural information and improves classification accuracy.

关键词： multi-head attention(MHA) structured-self attention(SSA) emotion classification deep learning bidirectional long-short-term memory(BiLSTM)