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Focal nodular hyperplasia of the liver in 86 patients

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Hepatobiliary & Pancreatic Diseases International 2007年第1期6卷 52-57页

作者： shen, ying-hao Fan, Jia Wu, Zhi-Quan Ma, Zeng-Chen Zhou, Xin-Da Zhou, Jian Qiu, Shuang-Jian Qin, Lun-Xiu Ye, Qin-Hai Sun, Hui-Chuan Huang, Xiao-Wu Tang, Zhao-You Fudan Univ Zhongshan Hosp Dept Liver Surg Shanghai 200032 Peoples R China

BACKGROUND: Focal nodular hyperplasia (FNH), the second most common benign hepatic tumor after hemangioma, is characterized by a stellate central scar and hyperplastic nodules. Although some large FNH may be associated with significant symptoms, more frequently they are discovered incidentally on physical examination or the work-up of unrelated symptoms. Since its nature and pathogenesis are still controversial, accurate diagnosis of FNH based on clinical presentation and radiographic studies is difficult. The purpose of this study was to explore the diagnosis and treatment of FNH. METHODS: Eighty-six FNH patients confirmed pathologically were treated at the Liver Cancer Institute in our hospital from 1996 to 2006. Their clinical manifestions, imaging presentation, pathological findings, and surgical results were analyzed retrospectively. RESULTS: Of the 86 patients with 99 foci, 54 were male and 32 female, with a mean age of 37 years. Eighty patients had a single solitary focus and 6 had multiple foci. Tumor diameter was less than 5 cm in 69 patients, 5-10 cm in 15, and more than 10 cm in 2. The overall rate of correct preoperative diagnosis was 59.3% (51/86) including 32.9% (26/79) by color Doppler flow imaging (CDFI), 60.3% (35/58) by CT, and 77.4% (24/31) by MRI. All the 86 patients underwent resection with good curative effect. CONCLUSIONS: CT and MRI are important diagnostic methods for FNH but it is difficult to make a definite preoperative diagnosis for partial classical and all non-classical FNH patients. We suggest that patients with clinical symptoms or with indefinite diagnosis should accept surgical removal.

关键词： liver focal nodular hyperplasia diagnosis treatment

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异步牵引电机磁场定向控制解耦算法的研究

铁道学报 2003年第1期25卷 26-29页

作者：沈滢郝荣泰北方交通大学电气工程学院北京100044

针对异步牵引电机,研究了磁场定向控制系统的电压解耦问题。就一种新的解耦算法,从动态响应、抗参数变化、弱磁区转矩响应等方面,借助理论分析和计算机仿真,与现有的解耦算法进行比较。研究表明:该方法更适合于大功率牵引电机的解耦计算。

关键词：异步牵引电机磁场定向控制解耦算法

Optimizing electronic structure through point defect engineering for enhanced electrocatalytic energy conversion

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Green Energy & Environment 2025年第1期10卷 109-131页

作者： Wei Ma Jiahao Yao Fang Xie Xinqi Wang hao Wan Xiangjian shen Lili Zhang Menggai Jiao Zhen Zhou Interdisciplinary Research Center for Sustainable Energy Science and Engineering(IRC4SE2) School of Chemical EngineeringZhengzhou UniversityHenan450001China

Point defect engineering endows catalysts with novel physical and chemical properties,elevating their electrocatalytic *** introduction of defects emerges as a promising strategy,effectively modifying the electronic structure of active *** optimization influences the adsorption energy of intermediates,thereby mitigating reaction energy barriers,altering paths,enhancing selectivity,and ultimately improving the catalytic efficiency of *** elucidate the impact of defects on the electrocatalytic process,we comprehensively outline the roles of various point defects,their synthetic methodologies,and characterization ***,we consolidate insights into the relationship between point defects and catalytic activity for hydrogen/oxygen evolution and CO_(2)/O_(2)/N_(2) reduction reactions by integrating mechanisms from diverse *** underscores the pivotal role of point defects in enhancing catalytic *** last,the principal challenges and prospects associated with point defects in current electrocatalysts are proposed,emphasizing their role in advancing the efficiency of electrochemical energy storage and conversion materials.

关键词： Point defect engineering Doping Vacancy Electrocatalysis Electronic structure

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一种评价页岩储层压裂液吸收的新方法

科学技术与工程 2016年第24期16卷 48-53页

作者：杨柳葛洪魁申颍浩中国石油大学(北京)油气资源与探测国家重点实验室北京102249

压裂液在毛细管力作用下自发吸入地层是导致页岩储层体积压裂返排率普遍低于30%的主要原因之一,有效评价页岩储层对压裂液的吸收是体积压裂优化设计、返排制度建立以及水锁伤害程度评估的基础,目前国内外尚未发现有效的评价方法。针对... 详细信息

压裂液在毛细管力作用下自发吸入地层是导致页岩储层体积压裂返排率普遍低于30%的主要原因之一,有效评价页岩储层对压裂液的吸收是体积压裂优化设计、返排制度建立以及水锁伤害程度评估的基础,目前国内外尚未发现有效的评价方法。针对渝东北下寒武统鲁家坪组典型页岩和三种不同的致密储层岩石开展自发渗吸对比实验,并对比研究了3种常用的渗吸表征方法,提出了评价页岩储层压裂液吸收的方法和参数。通过实验研究发现,无因次法和Olafuyi法可用于评价页岩储层压裂液吸收能力,在表征吸收速率和规律方面尚有不足;Makhanov法可用于表征压裂液吸收速率和规律,在评价储层吸收能力方面尚有不足。新方法采用自吸能力、初期自吸速率和后期自吸速率三参数对压裂液的吸收进行定量表征,很好地反映出压裂液吸收规律。压裂液吸收可分为三个阶段:初期渗吸段、过渡段和后期渗吸段,其中初期渗吸段是压裂液吸收的主要阶段;压裂液吸收的驱动力主要为毛细管力和黏土吸附力;黏土含量越高,压裂液自吸能力越强,伊蒙混层和蒙脱石的存在可以大大提高页岩自吸能力。新方法能够评价页岩压裂液吸收的快慢、总量和规律,可以用于不同地层之间的对比评价,且直观可靠,有利于在页岩气或致密气现场推广应用。

关键词：页岩气自吸毛细管力黏土

Electrode/Electrolyte Optimization‑Induced Double‑Layered Architecture for High‑Performance Aqueous Zinc‑(Dual)Halogen Batteries

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Nano-Micro Letters 2025年第3期17卷 121-137页

作者： Chengwang Zhou Zhezheng Ding shengzhe ying hao Jiang Yan Wang Timing Fang You Zhang Bing Sun Xiao Tang Xiaomin Liu School of Textiles and Clothing School of Chemistry and Chemical EngineeringQingdao UniversityQingdao 266071ShandongPeople’s Republic of China Centre for Clean Energy Technology School of Mathematical and Physical SciencesFaculty of ScienceUniversity of Technology SydneyUltimoNSW 2007Australia School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiang 453007HenanPeople’s Republic of China

Aqueous zinc-halogen batteries are promising candidates for large-scale energy storage due to their abundant resources,intrinsic safety,and high theoretical ***,the uncontrollable zinc dendrite growth and spontaneous shuttle effect of active species have prohibited their practical ***,a double-layered protective film based on zinc-ethylenediamine tetramethylene phosphonic acid(ZEA)artificial film and ZnF2-rich solid electrolyte interphase(SEI)layer has been successfully fabricated on the zinc metal anode via electrode/electrolyte synergistic *** ZEA-based artificial film shows strong affinity for the ZnF2-rich SEI layer,therefore effectively suppressing the SEI breakage and facilitating the construction of double-layered protective film on the zinc metal *** double-layered architecture not only modulates Zn2+flux and suppresses the zinc dendrite growth,but also blocks the direct contact between the metal anode and electrolyte,thus mitigating the corrosion from the active *** employing optimized metal anodes and electrolytes,the as-developed zinc-(dual)halogen batteries present high areal capacity and satisfactory cycling *** work provides a new avenue for developing aqueous zinc-(dual)halogen batteries.

关键词： Zn metal anodes Double-layered protective film Electrode/electrolyte optimization Aqueous zinc-(dual)halogen batteries

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火山岩气井井壁破坏预测可视化研究

计算机仿真 2016年第2期33卷 158-162页

作者：杨柳葛洪魁申颍浩周彤中国石油大学(北京)非常规天然气研究院北京102249 中国石油大学(北京)石油工程学院北京102249

针对井壁崩落和井壁漏失是钻井过程中井壁失稳破坏的主要形式,由于吉林油田松辽盆地深层致密火山岩气储层地层层序和岩性多样,井壁破坏机理复杂,目前还没有形成系统的方法来预测井壁破坏情况,大大影响了钻前可行性分析及钻井方案优化设... 详细信息

针对井壁崩落和井壁漏失是钻井过程中井壁失稳破坏的主要形式,由于吉林油田松辽盆地深层致密火山岩气储层地层层序和岩性多样,井壁破坏机理复杂,目前还没有形成系统的方法来预测井壁破坏情况,大大影响了钻前可行性分析及钻井方案优化设计。针对上述问题,提出了一种预测致密火山岩气井的井壁破坏的方法。以线弹性力学的基础理论为基础,对断层摩擦强度控制下的原地应力场和近井壁局部应力场叠加作用下的周向应力场进行分析,建立了致密火山岩气井井壁崩落和漏失模型。基于上述井壁破坏模型和理论推导,在Matlab数值仿真软件中,对井壁崩落和漏失情况进行预测和可视化仿真输出,并与井下的井壁破坏实际观测结果进行对比,验证预测方法的可靠性。仿真结果表明,致密火山岩气井的井壁破坏预测结果与工程实际吻合度较高,可视化仿真直观、形象、准确,可以很好地为火山岩气井施工现场井壁失稳问题的分析和预测提供依据。

关键词：井壁稳定可视化井壁崩落漏失

Chiral phosphoramidite ligand-modulated palladium auto-tandem catalysis for asymmetric dehydrogenative dienylation of imines with α-alkenes

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Science China Chemistry 2025年

作者： Zhong-sheng Nong hao-Fan Qian ying-Chun Chen Pu-sheng Wang Liu-Zhu Gong Hefei National Research Center for Physical Sciences at the Microscale and Department of Chemistry University of Science and Technology of China Key Laboratory of Drug Targeting and Drug Delivery System (Sichuan University) Ministry of Education and Sichuan Research Center for Drug Precision Industrial Technology West China School of Pharmacy Sichuan University School of Materials and Chemistry Southwest University of Science and Technology

The development of efficient processes allowing rapid access to complex chiral molecules from easily available alkenes is a long-term pursuit in the synthetic chemistry community. Transition metal-catalyzed asymmetric functionalization of allylic C–H bond represents a unique alternative toward this goal. However, enantioselective dehydrogenative transformation of olefins to value-added optically enriched molecules remains yet to be discovered. Here, we report a highly enantioselective dehydrogenative dienylation of imines with unactivated α-alkenes driven by the synergistic action of palladium complex and carboxylic acid. Chiral phosphoramidite ligands turned out to be superior in modulating the performance of palladium autotandem catalysis and allowed a broad range of α-alkenes and imines to be transformed into chiral dienylamines. Mechanistic studies suggest that the dienes could be in situ generated from α-alkenes through a palladium(0)-mediated dehydrogenative process in the presence of excess benzoquinone oxidants, and then participated in the Pd-chiral phosphoramidite-catalyzed intermolecular vinylogous-type addition to the imines activated by the carboxylic acid co-catalyst. Notably, the second β-H elimination occurring in the dienylation event might be the turnover-limiting step.

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低空经济的内涵、特征和运行模式

新疆师范大学学报（哲学社会科学版） 2025年第1期46卷 108-117,F0002页

作者：沈映春北京航空航天大学公共管理学院北京100083

低空经济作为低空飞行活动与产业融合的新型综合性经济形态,具有空间立体性、区域依赖性、数字生态性、产业融合性以及辐射带动性等特征。党和政府高度重视发展低空经济,将其确定为国家战略性新兴产业,各地加紧布局,发展势头良好。但具... 详细信息

低空经济作为低空飞行活动与产业融合的新型综合性经济形态,具有空间立体性、区域依赖性、数字生态性、产业融合性以及辐射带动性等特征。党和政府高度重视发展低空经济,将其确定为国家战略性新兴产业,各地加紧布局,发展势头良好。但具体实践中仍存在发展低空经济的体制机制不畅、技术创新支持不足、新型基础设施不全、产业领域需不断拓展等问题。针对上述问题,文本依据螺旋理论,提出“政产学研金服用”的低空经济开放式创新生态模式。

关键词：低空经济新质生产力战略性新兴产业开放式创新生态运行模式

Deciphering fungal metabolon coupling tandem inverse-electrondemand Diels-Alder reaction and semipinacol rearrangement for the biosynthesis of spiro polycyclic alkaloids

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Science China Chemistry 2025年第1期68卷 288-296页

作者： Shuai Liu Wen-Qiang Xu ying-Tong Di Man-Cheng Tang Ding-Kang Chen Ming-Ming Cao Yao-Wen Chang Hong-Yu Tang Chun-Mao Yuan Jun-Bo Yang Zhi-Li Zuo Han Guo Zi-Fei Xu ying Zeng Yun-Dong Wu Xiao-Jiang hao Key Laboratory of Phytochemistry and Natural Medicines (Chinese Academy of Sciences) Kunming Institute of Botany Chinese Academy of Sciences University of Chinese Academy of Sciences Lab of Computational Chemistry and Drug Design State Key Laboratory of Chemical Oncogenomics Peking University Shenzhen Graduate School shenzhen Bay Laboratory State Key Laboratory of Microbial Metabolism School of Life Sciences & Biotechnology Shanghai Jiao Tong University State Key Laboratory of Functions and Applications of Medicinal Plants Guizhou Medical University Molecular Biology Experimental Center Germplasm Bank of Wild Species in Southwest China Kunming Institute of Botany Chinese Academy of Sciences Yunnan Key Laboratory for Wild Plant Resources Kunming Institute of Botany Chinese Academy of Sciences Research Unit of Chemical Biology of Natural Anti-Virus Products Chinese Academy of Medical Sciences

In the intricate process of natural product biosynthesis, a metabolon can enhance metabolic flux by associating sequential enzymes. A fungal metabolon, comprising of flavin-dependent monooxygenase Spe F and P450 monooxygenase Spe G, is identified in the biosynthesis of spiro polycyclic alkaloids(+)-notoamide B and its diastereomer(+)-versicolamide B. Using notoamide E as a substance, Spe F/Spe G metabolon can control the stereoselectivity of its 2,3-epoxidation, followed by hydrogen atom ion at C-17 to generate reactive epoxide tau-m A with dienyl iminium unit. Subsequently,(+)-notoamide B and(+)-versicolamide B are produced via tandem nonenzymatic inverse-electron-demand Diels-Alder reaction and semipinacol rearrangement. This provides the first example of metabolon in the biosynthesis of spiro-prenylated indole alkaloids.

关键词： metabolon Diels-Alder reaction semipinacol rearrangement biosynthesis notoamides spiro polycyclic alkaloids