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Chinese Chemical Letters 2011年第7期22卷 811-814页

作者： Wei lin Li Qiu yan Luo fu lin yan School of Pharmacy Xinxiang Medical University Xinxiang 453003 China Department of Gynecological and Obstetric Third Affiliated Hospital to Xinxiang Medical University Xinxiang 453003 China

An environmentally friendly procedure for the preparation of 10-aryl-6,8-dimethyl-6,10-dihydro-5-oxa-6,8-diazaanthra[2,3- d] [ 1,3]dioxole-7,9-diones under thermal solvent-free conditions in the presence of cyanurie c... 详细信息

关键词： Bcnzodioxoles 3,4-Methylenedioxyphenol 1,3-Dimethylbarbituric acid Cyanuric chloride Solvent-free

A New Isopropenyl Benzofuran-type Tetramer from Ligularia stenocephala

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Chinese Chemical Letters 2003年第12期14卷 1253-1254页

作者： fu lin yan Ai Xia WANG Zhong Jian JIA Lei HE College of Chemistry and Chemical Engineering National Laboratory of Applied Organic ChemistryLanzhou UniversityLanzhou 730000

A new isopropenyl benzofuran-type tetramer was isolated from the roots of ligularia stenocephala and its structure was established by spectroscopic methods.

关键词： Compositae Ligularia stenocephala isopropenyl benzofuran-type tetramer.

Two new diterpenoids from Isodon serra

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Chinese Chemical Letters 2007年第11期18卷 1383-1385页

作者： fu lin yan Lai Bin Zhang Ji Xia Zhang Han Dong Sun Pharmacy College Xinxiang Medical University Xinxiang 453003 China Kunming Institute of Botuny Chinese Academy of Sciences Kunming 650204 China

From the aerial part of Isodon serra, two new ent-6,7-seco-kaurane-type diterpenoids, 15α,20β-dihydroxy-6β- methoxy-6,7- seco-6,20-epoxy-1,7-olide-ent-kaur-16-ene （1） and 6α,15α-dihydroxy-20-aldehyde-6,7-seco-6,11α-epoxy-1,7-olide-ent-kaur-16- ene （2） were isolated. Their structures were elucidated by spectroscopic means.

关键词： Labiatae Isodon serra ent-6,7-seco-Kaurane diterpenoid

A new guaianolide from the roots of Pterocypsela elata

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Chinese Chemical Letters 2013年第1期24卷 55-56页

作者： Yi-Xiao Bai Jing Tan fu-lin yan Ming-Ming Ding Xiang Wang Pharmacy College Xinxiang Medical University Third Clinical College of Xinxiang Medical University

In order to find more biologically active substances, we have carefully investigated the chemical constituents of Pterocypsela elata. One new guaianolide, （4S）-ll-methoxycarbonyl-guaiane- l（10）,5（6）,7（11）,8（9）-tetraen-6,12-olide was isolated from the EtOAc extracts of the roots of P. elata. Its structure was elucidated by various spectroscopic methods and confirmed by X-ray crystallographic analysis.

关键词： CompositaePterocypsela elataSesquiterpene lactonesGuaianolide

Two new ent-kaurane diterpenoids from Isodon excisoides

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Chinese Chemical Letters 2009年第2期20卷 201-203页

作者： Ji Xia Zhang Yong Xue Wang Zhi An He fu lin yan Han Dong Sun Pharmaceutical Laboratory Xinxiang Medical University Xinxiang 453003 China State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China

Two new ent-kaurane diterpenoids taihangexcisoidesin A and B （1 and 2）, were isolated from the EtOAc extract of the leaves of lsodon excisoides. Their structures were determined on the basis of spectroscopic methods.

关键词： Isodon excisoides ent-Kaurane Diterpenoid Taihangexcisoidesin A and B

Switched-capacitor Based Seven-level Boost Inverter with a Reduced Number of Devices

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 381-391页

作者： Weijie lin Jun Zeng Bo fu Zhixing yan Junfeng Liu School of Electric Power Engineering South China University of TechnologyGuangzhou 510641China WISDRI Engineering&Research Incorporation Limited Wuhan 430074China Department of Energy Aalborg UniversityAalborg 9220Denmark School of Automation Science and Engineering South China University of TechnologyGuangzhou 510641China

The conventional multilevel inverters(MLIs)have the disadvantages of numerous devices,incapacity of boost,unbalance for capacitor’s voltage,high complexity for control,and *** by this issue,a seven-level boost inverter(7LBI)based on a switched capacitor is presented for singlephase applications in this *** proposed 7LBI using only seven transistors can achieve seven output levels,1.5 voltage gain,and natural balance of capacitors’voltages without sensors or other auxiliary methods,which illustrates its suitability for the applications of renewable energy *** configuration of topology and operating principles are illustrated in *** natural balance of capacitors and capacitance calculations are deduced as ***,the comparative study is conducted for different types of *** results illustrate the merits of the proposed 7LBI with respect to reduced devices,lower voltage stress,and less power ***,a simulation for the proposed 7LBI with PWM modulation is realized based on the theoretical analysis;an experimental prototype is also implemented,verifying multilevel output,boost ability,natural balance for switched capacitors,and performance of transient response.

关键词： Multilevel inverters voltage gain natural balance renewable energy generation reduced number of elements

New ent-kaurane-type diterpenoids from Isodon nervosus

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Chinese Chemical Letters 2008年第4期19卷 441-443页

作者： fu lin yan Lan Qing Guo Ji Xia Zhang Su Ping Bai Han Dong Sun Pharmacy College Xinxiang Medical UniversityXinxiang 453003China Kunming Institute of Botany Chinese Academy of SciencesKunming 650204China

Two new ent-kaurane-type diterpenoids,6β,7β,13α-trihydroxy-1α-acetoxy-7α,20-epoxy-ent-kaur-16-en-15-one（1）and 15β- hydroxy-6,7-seco-6,11β：6,20-diepoxy-1α,7-olide-ent-kaur-16-ene（2）were isolated from the I... 详细信息

关键词： Labiatae Isodon nervosus ent-Kaurane diterpenoid

High sensitive pressure sensors based on multiple coating technique

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Chinese Physics B 2020年第2期29卷 442-445页

作者： Rizwan Zahoor Chang Liu Muhammad Rizwan Anwar fu-yan lin An-Qi Hu Xia Guo School of Electronic Engineering State Key Laboratory for Information Photonics and Optical CommunicationsBeijing University of Posts and TelecommunicationsBeijing 100876China

A multi-coating technique of reduced graphene oxide(RGO)was proposed to increase the sensitivity of paper-based pressure *** maximum sensitivity of 17.6 kPa^-1 under the 1.4 kPa was *** electrical sensing mechanism is attributed to the percolation *** paper pressure sensors were applied to monitor the motor vibration,which indicates the potential of mechanical flaw detection by analyzing the waveform difference.

关键词： paper sensor reduced graphene oxide sensitivity

Normal sperm head morphometric reference values in fertile Asian males

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Asian Journal of Andrology 2024年第3期26卷 315-320页

作者： Ye-lin Jia Ying-Bi Wu lin Yu yan Zheng Ting-Ting yang yan-Yun Wang Bin Zhou lin Zhang fu-Ping Li Laboratory of Andrology West China Second University Hospital Human Sperm BankChengdu 610000China Laboratory of Molecular Translational Medicine Center for Translational MedicineChengdu 610061China Key Laboratory of Birth Defects and Related Diseases of Women and Children(Sichuan University) Ministry of EducationChengdu 610061China NHC Key Laboratory of Chronobiology West China Second University HospitalSichuan UniversityChengdu 610000China

Sperm head morphology is crucial for male factor infertility diagnosis and assessment of male reproductive *** are available to analyze sperm head morphology,but they are limited by poor methodology comparability and *** study aimed to explore comprehensive and new normal morphometric reference values for spermatozoa heads infertile Asian *** automated sperm morphology analysis system captured 23152 stained spermatozoa from confirmed *** these samples,1856 sperm head images were annotated by three experienced laboratory technicians as“normal”.Weemployed 14 novel morphometric features to describe sperm head size(head length,head width,length/width ratio,and girth),shape(ellipse intersection over union,girth intersection over union,short-axis symmetry,and long-axis symmetry),area(head,acrosome,postacrosomal areas,and acrosome area ratio),and degrees of acrosome and nuclear *** straight-forwardmethod for the morphometric analysis of sperm by accurate visual measurements is clinically *** measured parameterspresent valuable information to establish morphometric reference intervals for normal sperm heads in fertile Asian *** detailed measurement data will be valuable for interlaboratory comparisons and technician *** vitro fertilizationand andrology laboratory technicians can use these parameters to perform objective morphology evaluation when assessing malefertilization potential.

关键词： fertile Asian males head morphometric reference value normal spermatozoa

Deep learning CNN-APSO-LSSVM hybrid fusion model for feature optimization and gas-bearing prediction

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Petroleum Science 2024年第4期21卷 2329-2344页

作者： Jiu-Qiang yang Nian-Tian lin Kai Zhang yan Cui Chao fu Dong Zhang College of Earth Sciences and Engineering Shandong University of Science and Technology Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and Technology Transportation Institute of Inner Mongolia University Key Laboratory of Gas Hydrate Qingdao Institute of Marine Geology Ministry of Natural Resources

Conventional machine learning(CML) methods have been successfully applied for gas reservoir prediction. Their prediction accuracy largely depends on the quality of the sample data; therefore, feature optimization of the input samples is particularly important. Commonly used feature optimization methods increase the interpretability of gas reservoirs; however, their steps are cumbersome, and the selected features cannot sufficiently guide CML models to mine the intrinsic features of sample data efficiently. In contrast to CML methods, deep learning(DL) methods can directly extract the important features of targets from raw data. Therefore, this study proposes a feature optimization and gas-bearing prediction method based on a hybrid fusion model that combines a convolutional neural network(CNN)and an adaptive particle swarm optimization-least squares support vector machine(APSO-LSSVM). This model adopts an end-to-end algorithm structure to directly extract features from sensitive multicomponent seismic attributes, considerably simplifying the feature optimization. A CNN was used for feature optimization to highlight sensitive gas reservoir information. APSO-LSSVM was used to fully learn the relationship between the features extracted by the CNN to obtain the prediction results. The constructed hybrid fusion model improves gas-bearing prediction accuracy through two processes of feature optimization and intelligent prediction, giving full play to the advantages of DL and CML methods. The prediction results obtained are better than those of a single CNN model or APSO-LSSVM model. In the feature optimization process of multicomponent seismic attribute data, CNN has demonstrated better gas reservoir feature extraction capabilities than commonly used attribute optimization methods. In the prediction process, the APSO-LSSVM model can learn the gas reservoir characteristics better than the LSSVM model and has a higher prediction accuracy. The constructed CNN-APSO-LSSVM mode

关键词： Multicomponent seismic data Deep learning Adaptive particle swarm optimization Convolutional neural network Least squares support vector machine Feature optimization Gas-bearing distribution prediction