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Acta Biochimica et Biophysica Sinica 2004年第3期36卷 206-210页

作者： Lian-Fei TANG, Xin-yuan yi*, Xian-fang ZENG, Lin-Qian WANG, and Shun-Ke ZHANG Department of Parasitology, Central South University Xiangya School of Medicine, Changsha 410078, China Department of Parasitology Central South University Xiangya School of Medicine Changsha 410078 China

In an attempt to isolate and identify the antigenic epitopes on ferritin of Schistosoma japonicum (SjFer) and to test their protective potentiality against Schistosoma japonicum (S.j), polyclonal antisera against SjFer was prepared to screen a 12-mer random peptide library. Three rounds of biopan- ning were performed and resulted in an enrichment. Six peptides selected randomly from the third elute were all found to be positive by evaluating the binding to anti-SjFer sera by ELISA and Western blot- ting. Three amino acid sequences were deduced from the six phage clones by sequencing. When they were used to vaccinate mice, the three peptides could induce significant reduction in adult worms (26.7%, 20.4%, and 25.9%) as well as in liver eggs per gram (LEPG) (40.0%, 38.2%, and 40.8%). This result showed that three mimotopes on SjFer were obtained and they could induce significant protective efficacy against S.j.

关键词： phage displayed peptide library epitope Schistosoma japonicum ferritin

Design of Equal Precision Frequency Meter Based on FPGA

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Engineering（科研） 2012年第10期4卷 696-700页

作者： yi-yuan fang Xue-jun Chen College of Electrical and Electronic Engineering Shanghai University of Engineering Science Shanghai China

To overcome the shortcoming that the traditional frequency measurement method does not meet the requirement of equal precision, a design method of equal precision frequency meter based on FPGA is proposed. The system modules are all realized in Altera’s FPGA chip EP2C35F672C8. Experimental results show that the system can measure frequencies with equal precision in the whole frequency range, and the measurement error is small. It achieves the requirement of equal precision measurements.

关键词： FPGA Equal Precision Frequency Measurement

Pressure-induced anomalous insulating behavior in frustrated iridate La_(3)Ir_(3)O_(11)

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Chinese Physics B 2021年第6期30卷 547-551页

作者： Chun-Hua Chen Yong-Hui Zhou ying Zhou yi-fang yuan Chao An Xu-Liang Chen Zhao-Ming Tian Zhao-Rong Yang Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions High Magnetic Field LaboratoryChinese Academy of SciencesHefei 230031China Science Island Branch of Graduate School University of Science and Technology of ChinaHefei 230026China Institutes of Physical Science and Information Technology Anhui UniversityHefei 230601China School of Physics and Wuhan National High Magnetic Field CenterHuazhong University of Science and TechnologyWuhan 430074China High Magnetic Field Laboratory of Anhui Province Hefei 230031China

The geometrically frustrated iridate La_(3)Ir_(3)O_(11) with strong spin–orbit coupling and fractional valence was recently predicted to be a quantum spin liquid candidate at ambient conditions. Here, we systematically investigate the evolution of structural and electronic properties of La_(3)Ir_(3)O_(11) under high pressure. Electrical transport measurements reveal an abnormal insulating behavior rather than metallization above a critical pressure P_(c) ~ 38.7 GPa. Synchrotron x-ray diffraction(XRD)experiments indicate the stability of the pristine cubic KSbO_(3)-type structure up to 73.1 GPa. Nevertheless, when the pressure gradually increases across P_(c), the bulk modulus gets enhanced and the pressure dependence of bond length d_(Ir-Ir) undergoes a slope change. Consistent with the XRD data, detailed analyses of Raman spectra reveal an abnormal redshift of Raman mode and a change of Raman intensity around P_(c). Our results demonstrate that the pressure-induced insulating behavior in La_(3)Ir_(3)O_(11) can be assigned to the structural modification, such as the distortion of IrO_6 octahedra. These findings will shed light on the emergent abnormal insulating behavior in other 5 d iridates reported recently.

关键词： high pressure 5d iridates semimetal–insulator transition crystal structure

基于强迫振动的全捷联导引头隔离度在线抑制技术

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北京理工大学学报 2015年第12期35卷 1243-1249页

作者：袁亦方林德福杨涛北京理工大学宇航学院北京100081 西安现代控制技术研究所陕西西安710065

基于全捷联导引头隔离度离线标定精度较差且难以有效抑制隔离度对制导控制系统造成的影响,提出了基于强迫振动的全捷联导引头隔离度在线估计与抑制算法,并研究了算法参数取值对估计和抑制效果的影响;针对隔离度抑制效果受测量噪声影响... 详细信息

基于全捷联导引头隔离度离线标定精度较差且难以有效抑制隔离度对制导控制系统造成的影响,提出了基于强迫振动的全捷联导引头隔离度在线估计与抑制算法,并研究了算法参数取值对估计和抑制效果的影响;针对隔离度抑制效果受测量噪声影响较大的问题,设计了基于卡尔曼滤波技术的改进方法.仿真结果表明,该算法可以实现对全捷联导引头刻度尺误差引起的隔离度的估计,将估计结果进行前馈补偿可有效抑制隔离度对导弹制导控制系统的影响.

关键词：隔离度强迫振动估计与抑制技术卡尔曼滤波前馈补偿

Pressure-induced enhancement of optoelectronic properties in PtS2

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Chinese Physics B 2018年第6期27卷 345-349页

作者： yi-fang yuan Zhi-Tao Zhang Wei-Ke Wang Yong-Hui Zhou Xu-Liang Chen Chao An Ran-Ran Zhang ying Zhou Chuan-Chuan Gu Liang Li Xin-Jian Li Zhao-Rong Yang Department of Physics and Laboratory of Material Physics Zhengzhou UniversityZhengzhou 450052China Anhui Provincial Key Laboratory of Condensed Matter Physics at Extreme Conditions High Magnetic Field LaboratoryChinese Academy of SciencesHefei 230031China Synergetic Innovation Center for Quantum Effects and Application Key Laboratory of Low-dimensional Quantum Structures and Quantum Control of Ministry of EducationCollege of Physics and Information ScienceHunan Normal UniversityChangsha 410081China State Key Laboratory of Material Processing and Die and Mould Technology School of Materials Science and EngineeringHuazhong University of Science and Technology(HUST)Wuhan 430074China Institute of Physical Science and Information Technology Anhui UniversityHefei 230601China

PtS2, which is one of the group-10 transition metal dichalcogenides, attracts increasing attention due to its extraordinary properties under external modulations as predicted by theory, such as tunable bandgap and indirect-to-direct gap transition under strain; however, these properties have not been verified experimentally. Here we report the first experimental exploration of its optoelectronic properties under external pressure. We find that the photocurrent is weakly pressuredependent below 3 GPa but increases significantly in the pressure range of 3 GPa–4 GPa, with a maximum ～ 6 times higher than that at ambient pressure. X-ray diffraction data shows that no structural phase transition can be observed up to26.8 GPa, which indicates a stable lattice structure of PtS2 under high pressure. This is further supported by our Raman measurements with an observation of linear blue-shifts of the two Raman-active modes to 6.4 GPa. The pressure-enhanced photocurrent is related to the indirect-to-direct/quasi-direct bandgap transition under pressure, resembling the gap behavior under compression strain as predicted theoretically.

关键词： high pressure optoelectronic properties transition metal disulfide

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VHL综合征1例

中国临床医学影像杂志 2015年第10期26卷 756-757页

作者：袁艺芳陈东泸州医学院附属医院放射科四川泸州646000

病例男,42岁。因颅内占位切除术后13年，左侧小脑占位切除术后1年．发现椎管内占位1年就诊。患者13年前无明显诱因出现头痛伴恶心呕吐、呕吐后不缓解，CT提示“双侧小脑及椎管内占位”。行颅内占位切除术。

关键词：血管母细胞瘤囊肿体层摄影术 X线计算机磁共振成像

基于最大似然估计和混合梯度优化的射手模型辨识

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兵工学报 2018年第12期39卷 2399-2409页

作者：吴骏雄林德福王辉袁亦方北京理工大学无人机自主控制技术北京市重点实验室北京100081 北京特种机电研究所北京100012

光纤制导过程中射手对于光电显示的响应及其控制行为将直接影响弹药的制导控制性能。针对此问题,将最大似然估计法应用于射手模型辨识研究中。为解决辨识过程中遇到的非线性优化问题,采用遗传算法和高斯-牛顿优化算法混合策略提高寻找... 详细信息

光纤制导过程中射手对于光电显示的响应及其控制行为将直接影响弹药的制导控制性能。针对此问题,将最大似然估计法应用于射手模型辨识研究中。为解决辨识过程中遇到的非线性优化问题,采用遗传算法和高斯-牛顿优化算法混合策略提高寻找全局最优解的概率,并使用单纯形法提高算法鲁棒性。基于交叉原理提出适用于导引头回路的精确模型,设计仿真实验平台并进行了多轮次人在回路实验,将输出误差框架下的最大似然估计方法成功应用于实验数据中。结果表明:混合梯度优化算法能够找到全局最优值,辨识模型能够准确反映射手本身的动态特性,辨识方法和辨识的射手模型对于光纤寻的弹药制导控制系统设计具有一定的实际意义。

关键词：光纤图像制导武器射手模型交叉模型最大似然估计混合梯度优化输出误差法遗传算法高斯-牛顿优化

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质子交换LiNbO_3光波导的特性研究

光谱学与光谱分析 2006年第12期26卷 2346-2349页

作者：符运良何猛雄袁一方海南师范学院物理系海南海口571158 海南师范学院化学系海南海口571158 上海理工大学光学与电子信息工程学院上海200093

采用X射线衍射谱法和红外吸收光谱法对质子交换和退火质子交换LiNbO3光波导的特性进行了研究。研究结果表明:在LiNbO3晶体衬底X射线衍射主峰的左侧出现质子交换LiNbO3光波导的伴峰,则质子交换使光波导层Li1-xHxNbO3的晶格常数比衬底的... 详细信息

采用X射线衍射谱法和红外吸收光谱法对质子交换和退火质子交换LiNbO3光波导的特性进行了研究。研究结果表明:在LiNbO3晶体衬底X射线衍射主峰的左侧出现质子交换LiNbO3光波导的伴峰,则质子交换使光波导层Li1-xHxNbO3的晶格常数比衬底的晶格常数稍大,产生垂直于表面的应变,波导经过退火后,伴峰向主峰靠近,应变减少。质子交换波导中的OH-基团的红外吸收光谱在3 500和3 300 cm-1处存在特征峰,波导经过退火后,3 300 cm-1处的特征峰基本消失,而3 500 cm-1处的吸收强度基本不变。实验还表明,OH-在3 500 cm-1处吸收带的积分面积基本与交换时间的开方呈正比例关系。

关键词：质子交换 LiNbO3光波导 X射线谱红外吸收光谱

评估日本简易食盐问卷在中国高血压人群中的适用性

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中华高血压杂志 2022年第9期30卷 841-848页

作者：袁亦方王鸿懿孙宁玲北京大学人民医院高血压研究室北京100044 北京大学临床研究所

目的评估日本简易食盐问卷在我国高血压人群中的适用性。方法该研究为一项多中心横断面研究。对来自全国10家医院的734例高血压患者,通过现场调查采集日本简易食盐问卷信息,同时采用离子选择电极法测定24 h尿钠排泄。采用Pearson相关性... 详细信息

目的评估日本简易食盐问卷在我国高血压人群中的适用性。方法该研究为一项多中心横断面研究。对来自全国10家医院的734例高血压患者,通过现场调查采集日本简易食盐问卷信息,同时采用离子选择电极法测定24 h尿钠排泄。采用Pearson相关性分析评估日本简易食盐问卷整体得分与24 h尿钠的相关性。以24 h尿钠为金标准,绘制受试者工作特征(ROC)曲线评价该问卷诊断尿钠超标的效能,描述灵敏度、特异度等指标。采用线性模型对与24 h尿钠相关的高盐行为进行单因素分析和多因素分析。结果受试者平均年龄为(55.8±14.7)岁,女性占44%,平均尿钠(142.8±81.1)mmol/d,相当于食钠盐8.4 g/d,日本简易食盐问卷分数(10.7±5.0)分。日本简易食盐问卷分数与实测24 h尿钠的相关性为0.23(P<0.01)。不同问卷分数段区分度欠佳,且在0~8分(对应食盐摄入量低)时已达24 h尿钠超标阶段(119.3 mmol/d)。日本简易食盐问卷判断尿钠超标的曲线下面积为0.60(95%CI 0.55~0.64),以日本简易食盐问卷分数≥14分作为判断尿钠超标的标准,灵敏度仅为28.8%,特异度为81.0%。多因素分析显示,饭量大、在外就餐、经常酱油拌菜、经常食用面条等膳食习惯与24 h尿钠增加相关。结论日本简易食盐问卷分数与我国24 h尿钠实测值呈弱相关,现有判定标准低估了24 h尿钠,不宜直接应用于我国高血压人群。

关键词：日本简易食盐问卷适用性筛查尿钠排泄高血压

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采用圆形匹配限制框的指纹特征点匹配算法

上海理工大学学报 2008年第6期30卷 581-584页

作者：应捷郑继红袁一方上海理工大学光电信息与计算机工程学院上海200093

介绍了指纹特征点的匹配原理,提出了一种改进的实时指纹特征点匹配算法,并对算法性能进行了实验研究.给出了错误匹配率(FMR)和错误不匹配率(FNMR)随阈值变化的情况及算法的ROC曲线.得到算法的等错误率(EER)为1.8%,最小FMR(ZeroFNMR)为6.... 详细信息

介绍了指纹特征点的匹配原理,提出了一种改进的实时指纹特征点匹配算法,并对算法性能进行了实验研究.给出了错误匹配率(FMR)和错误不匹配率(FNMR)随阈值变化的情况及算法的ROC曲线.得到算法的等错误率(EER)为1.8%,最小FMR(ZeroFNMR)为6.8%,平均匹配时间为0.1 s.算法在指纹库FVC2004上的实验结果表明,算法性能较好,适合于实时指纹识别系统.

关键词：指纹匹配算法特征点等错误率