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文史哲 2014年第1期 165-168页

作者： Yang Yi li Zhen Chen lai

Effect of Mirena placement on reproductive hormone levels at different time intervals after artificial abortion

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World Journal of Clinical Cases 2022年第2期10卷 511-517页

作者： Xiao-Xiao Jin ling Sun Xiao-li lai Jie li Mei-li liang Xia Ma Department of Obstetrics and Gynecology Zhejiang Taizhou HospitalTaizhou 317000Zhejiang ProvinceChina

BACKGROUND Improper methods of contraception greatly increase the risk of abortion,cervical or endometrial lesions,and the number of recurrent artificial *** complications result in the deterioration of a patient’s ***,the proportion of artificial abortions is highest among unmarried *** of an intrauterine device,such as the Mirena,after an artificial abortion may decrease the likelihood of an endometrial injury caused by recurrent abortions while significantly improving its contraceptive *** To discuss the effect of Mirena placement on reproductive hormone levels at different time points after an artificial *** Women(n=119)undergoing an artificial abortion operation were divided into the study(n=56)and control(n=63)*** the study group,the Mirena was inserted immediately after the artificial abortion,whereas in the control group,it was inserted 4–7 d after the onset of the first menstrual cycle after *** participants were followed-up for 6 mo to observe the continuation and expulsion rates and adverse reactions and to measure the levels of serum estradiol(E2),follicle stimulating hormone(FSH),and luteinizing hormone(LH).RESULTS The continuation rates were 94.64%and 93.65%in the study group and the control group,*** expulsion rates were 1.79%and 3.17%in the study group and the control group,*** was no statistically significant difference between the two groups(P>0.05).There were also no statistically significant differences in the proportion of patients with bacterial vaginitis,trichomonas vaginitis,or cervicitis between the groups(P>0.05).Six months after Mirena placement,E2 Levels were 45.50±7.13 pg/mL and 42.91±8.10 pg/mL,FSH 13.60±3.24 mIU/mL and 14.54±3.11 mIU/mL,and LH 15.11±2.08 mIU/mL and 14.60±3.55 mIU/mL in the study and control groups,*** were no significant differences in hormone levels between the two groups(P>0.05).There were also no stat

关键词： Artificial abortion operation Mirena intrauterine device Sex hormone Clinical effect

Ab Initio Study on Structural and Magnetic Properties of Ni-Pd and Ni-Pt linear and Zigzag Nanowires

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Communications in Theoretical Physics 2009年第7期52卷 123-127页

作者： CHE Xing-lai li Jia-Hao DAI Ye liU Bai-Xin Advanced Materials Laboratory Department of Materials Science and Engineering Tsinghua University Beijing 100084China

Employing the accurate frozen-core full-potential projector augmented-wave method,the self-consistentelectronic structure calculations were carried out on pure Ni,Pd,Pt and mixed Ni-Pd and Ni-Pt free-standing linear andzigzag *** bond lengths for all these systems are generally increased as their structures change from the linearto the zigzag *** bond lengths for Ni-Pd and Ni-Pt wires are in between the values of corresponding pure systemand the bond angles around 60° suggesting the possible formation of Ni-Pd and Ni-Pt bimetallic *** mixedNi-Pd and Ni-Pt chains,the Ni,Pd,and Pt atoms have quite high local magnetic *** calculations suggestthat the magnetic moments in linear nanowires are generally larger than the ones of corresponding zigzag *** found that there is hybridization between Ni 3d and Pd 4d,Ni 3d and Pt 5d states,which may significantly affectstructural stability and magnetism of Ni-Pd and Ni-Pt nanowires.

关键词： Ab initio study magnetism nanowires

Geomorphic-centered Classification of Wetlands on the Qinghai-Tibet Plateau, Western China

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Journal of Mountain Science 2013年第4期10卷 632-642页

作者： GAO Jay li Xi-lai Gary BRIERLEY Alan CHEUNG YANG Yuan-wu School of Environment University of Auckland Private Bag 92019Auckland New Zealand College of Agriculture and Animal Husbandry Qinghai University

In this paper a geomorphic-centered system was proposed for classifying the wetlands on the Qinghai-Tibet Plateau in western China, where the flora comprises primarily grasses. Although the geomorphic properties (e.g., elevation and morphology) of wetlands form the primary criteria of classification, this system also takes hydrological processes into implicit consideration. It represents an improvement over the hydrogeomorphic perspective as the relative importance of the two components (wetness and landform) of wetlands is clearly differentiated. This geomorphic-centered perspective yields insights into the hydrogeomorphic dynamics of plateau wetlands while indicates their vulnerability to change and degradation indirectly. According to this geomorphic-centered perspective, all plateau wetlands fall into one of the seven types of alpine, piedmont, valley, terrace, floodplain, lacustrine, and riverine in three elevational categories of upland, midland, and lowland. Upland (alpine and piedmont) wetlands with the steepest topography are the most sensitive to change whereas midland (floodplain, terrace and valley) wetlands are less vulnerable to degradation owing to a high water reserve except terrace wetlands. They have a dry surface caused by infrequent hydrological replenishment owing to their higher elevation than the channel. Low lying (lacustrine and riverine) wetlands are the most resilient. The geomorphic-centered perspective developed in this paper provides a framework for improving recognition and management of wetlands on the Plateau. Resilient wetlands can be grazed more intensively without the risk of degradation. Fragile and vulnerable wetlands require careful managementto avoid degradation.

关键词： Plateau wetlands Geomorphieclassification Wetland vulnerability Qinghai-TibetPlateau

Scalable and High-Quality Monolayer Graphene Transfer onto Polymer Membranes Assisted by Camphor

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Chinese Journal of Polymer Science 2024年第12期42卷 1986-2001,I0011页

作者： Jun-Kan Yue Jing liang Qiao-Yu Tan Man Chen Jing-Wen li Qing Guo Run-lai li Qiang Fu College of Polymer Science&Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu610065China

The quest for scalable integration of monolayer graphene into functional composites confronts the bottleneck of high-fidelity transfer onto substrates,crucial for unlocking graphene’s full potential in advanced *** this,our research introduces the camphor-assisted transfer(CAT)method,a novel approach that surmounts common issues of residue and structural deformation endemic to existing *** in the sublimation dynamics of camphor,the CAT method achieves a clean,contiguous transfer of centimeter-scale monolayer graphene onto an array of polymer films,including ultra-thin polyethylene *** resultant ultrathin graphene-polyethylene(gPE)films,characterized by their exceptional transparency and conductivity,reveal the CAT method’s unique ability to preserve the pristine quality of graphene,underscoring its practicality for preparing flexible transparent electrodes by monolayer ***-depth mechanism investigation into the camphor sublimation during CAT has led to a pivotal realization:the porosity of the target polymer substrate is a determinant in achieving high-quality graphene *** that camphor sublimates initially from the polymer side is crucial to prevent the formation of wrinkles or delamination of *** extensive examination of CAT on a spectrum of commonly used polymer films,including PE,PP,PTFE,PI and PET,we have confirmed this important *** discovery offers crucial guidance for fabricating monolayer graphene-polymer composite films using methods akin to CAT,underscoring the significance of substrate selection in the transfer process.

关键词： Polyethylene Monolayer graphene Camphor Graphene/polymer composites van der Waals interaction

Center Conditions and Bifurcation of limit Cycles at Nilpotent Critical Point in a Quintic Lyapunov System

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Journal of Mathematical Research and Exposition 2011年第5期31卷 937-945页

作者： Feng li Yin lai JIN School of Science Linyi University Shandong 276005 P. R. China

In this paper, center conditions and bifurcation of limit cycles at the nilpotent critical point in a class of quintic polynomial differential system are investigated. With the help of computer algebra system MATHEMATICA, the first 8 quasi Lyapunov constants are deduced. As a result, the necessary and sufficient conditions to have a center are obtained. The fact that there exist 8 small amplitude limit cycles created from the three-order nilpotent critical point is also proved. Henceforth we give a lower bound of cyclicity of three-order nilpotent critical point for quintic Lyapunov systems.

关键词： three-order nilpotent critical point center-focus problem bifurcation of limit cycles quasi-Lyapunov constant.

Leaching and mass transfer characteristics of elements from ion-adsorption type rare earth ore

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Rare Metals 2015年第5期34卷 357-365页

作者： Yan-Fei Xiao Zong-Yu Feng Gu-Hua Hu li Huang Xiao-Wei Huang Ying-Ying Chen Ming-lai li National Engineering Research Center for Rare Earth Materials General Research Institute for Nonferrous Metals Grirem Advanced Materials Co. Ltd. Chalco Guangxi Nonferrous Rare Earth Development Co. Ltd. School of Chemical Engineering China University of PetroleumBeijing

The differences in the leaching and mass transfer characteristics of ion-adsorption type rare earth ore between rare earth and non-rare earth impurities were investigated. It is determined that the leaching kinetics of rare earths （REs）, Mg and Ca could be described by the shrinking-core model. The leaching rate is controlled by inner diffusion and is in the order of Mg 〉 Ca 〉 RE. The apparent activation energy is 8.48, 6.79 and 6.32 kJ·mol^-1, respectively. In leaching system of Al, the leaching efficiency decreases with the increase in temperature because of hydrolysis reactions. The leaching efficiency of aluminum increases firstly and then decreases with the passage of time when the temperature is higher than 35 ℃. Besides, there is a good consistency in leaching characteristics and mass transfer, and the order of the time-to- peak is Mg 〈 Ca 〈 RE 〈 Al. Therefore, rare earth and non-rare earth may be partly separated by expanding the separation coefficient. The research could provide a theoretic basis for the separation of rare earth and non-rare earth impurities. Furthermore, compound leaching with magnesium salt and calcium salt is innovatively proposed to solve the problem of calcium and magnesium nutrient loss in the soil as well as eliminate ammonia-nitrogen emissions from the source.

关键词： impurities Rare earth Leaching Non-rare earth Mass transfer

Spectral Characteristics of liSrBO_3:Tb^(3+) Green Phosphor

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Chemical Research in Chinese Universities 2009年第5期25卷 610-613页

作者： li Pan-lai WANG Zhi-jun YANG Zhi-ping GUO Qing-lin College of Physics Science ＆ Technology Hebei University Baoding 071002 P. R. China

liSrBO3：Tb^3＋ green phosphor was synthesized by means of a solid state reaction and its spectral characteristics were studied. The emission spectrum of liSrBO3：Tb^3＋ consists of four major bands at 486, 544, 595 and 620 nm under the excitation of near ultraviolet irradiation, which are originated from the ^5Da→^7F6, ^5D4→^7F5, ^5D4→^7F4 and ^5D4→^7F3 characteristic transitions of Tb^3＋, respectively. Monitored at 544 nm, the excitation spectrum of the phosphor extends from 220 nm to 390 nm, with the excitation peaks centered at 242, 277, 368 and 381 nm, respectively. The effect of Tb^3＋ concentration on the emission intensity of liSrBO3：Tb^3＋ was also investigated. The results show that firstly the intensity increases with increasing Tb^3＋ concentration, reaches a maximum value at 3%（molar fraction） Tb^3＋ and then decreases, showing a concentration self-quenching, whose mechanism is proposed as a d-d interaction based on Dexter theory. The emission intensity of liSrBO3：Tb^3＋ was enhanced by co-doping li^＋, Na^＋ and K^＋.

关键词： liSrBO3:Tb^3+ Green phosphor Spectral characteristics

Electromagnetic scattering and imaging simulation of extremely large-scale sea-ship scene based on GPU parallel technology

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Journal of Electronic Science and Technology 2024年第2期22卷 16-23页

作者： Cheng-Wei Zhang Zhi-Qin Zhao Wei Yang li-lai Zhou Hai-Yu Zhu Southwest China Institute of Electronic Technology Chengdu610036China School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu611731China Tencent Company Shenzhen518054China

Aiming to solve the bottleneck problem of electromagnetic scattering simulation in the scenes of extremely large-scale seas and ships,a high-frequency method by using graphics processing unit(GPU)parallel acceleration technique is *** the implementation of different electromagnetic methods of physical optics(PO),shooting and bouncing ray(SBR),and physical theory of diffraction(PTD),a parallel computing scheme based on the CPU-GPU parallel computing scheme is realized to balance computing ***,a multi-GPU framework is further proposed to solve the computational difficulty caused by the massive number of ray tubes in the ray tracing *** using the established simulation platform,signals of ships at different seas are simulated and their images are achieved as *** is shown that the higher sea states degrade the averaged peak signal-to-noise ratio(PSNR)of radar image.

关键词： Multi graphics processing unit Radar imaging Sea-ship Shooting and bouncing rays