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Magnetic Field Dissipation in Dense Molecular Clouds

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Chinese Physics Letters 1998年第3期15卷 200-202页

作者： mao xin-jie TONG Yi Astronomy Department Beijing Normal UniversityBeijing 100875

In dense molecular clouds the grains become the main charged *** the hydrogen gas density reaches as high as nH=10^(11)cm^(-3) and the grains are assumed to be small polycyclic aromatic hydrocarbons(PAHs),the lower hybrid drift instability develops,leading to the creation of anomalous electric conductivity,which makes the magnetic Reynold's number of the system R_(M)~1 indicating the dissipation of magnetic *** the gas density continues to go up and over10^(11)cm_(-3),the collision frequency between PAHs and gas particles becomes larger than the plasma frequency,resulting in the collision process being *** that case the magnetic field also dissipates because R_(M)~1 is still kept.

关键词： collision magnetic assumed

Generation of High Speed Particles in Herbig--Haro Flow Regions

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Chinese Physics Letters 2001年第2期18卷 307-309页

作者： YAN Hui-Rong mao xin-jie Chinese Academy of Sciences-Peking University Joint Beijing Astrophysics Center Peking UniversityBeijing 100871 Department of Geophysics Peking UniversityBeijing 100871 Department of Astronomy Beijing Normal UniversityBeijing 100875

A mechanism is presented for generating high speed particles in Herbig-Haro flow coming from accretion disks associated with *** disks are threaded with weak magnetic field lines,in which the magnetorotational instability results in magnetohydrodynamic *** the turbulent waves accelerate the thermal particles out of the accretion disks to a few hundred kilometres per second,forming the high speed particles of optical jets in star-forming regions.

关键词： turbulence turbulent generating

Acceleration and Emission Mechanism for Wisps in the Crab Nebula

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Chinese Physics Letters 1998年第11期15卷 854-855页

作者： JING Hai-rong TONG Yi mao xin-jie Department of Astronomy Beijing Normal UniversityBeijing 100875

A new acceleration and emission mechanism is presented for wisps in the crab *** is suggested that the energy of ultra-relativistic electrons comes mainly from Langmuir wave turbulence acceleration and synchrotron absorption acceleration,then they give rise to synchrotron *** wave turbulence acceleration is the dominant mechanism atε≤ε*,while synchrotron absorption acceleration is more important atε>ε*.The energy diffusion equation is investigated for ultra-relativistic electrons undergoing different acceleration and derive power-law *** wisp 1 region,the synchrotron emission spectra are obtained,and they are x-rays,optical but not *** results are consistent with observations.

关键词： acceleration solution. turbulence

Outflows of Massive Stars in Cluster

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Chinese Physics Letters 1998年第4期15卷 310-312页

作者： mao xin-jie QIU Hong-mei WANG Yu-chun Department of Astronomy Beijing Normal UniversityBeijing 100875

Massive stars often tend to be in cluster when they form in molecular clouds,and bipolar molecular outflows occur during the forming process of *** the basis of newly observed bipolar molecular outflows associated with massive stars,three properties are proposed to statistically identify massive stars whether in cluster or not as the driving engines of the *** clustering massive stars with some exceptions,their outflow collimation factors are generally poor and less than two,and the correlations of the flow momentum rate and the mass flow rate with the central source bolometric luminosity deviate the ones for selected well-resolved 16 flows.

关键词： stars massive source

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双模射频IC卡读写器天线设计

上海理工大学学报 2012年第3期34卷 303-306页

作者：毛歆杰袁焱陈玮上海交通大学电子电气与信息工程学院上海200240 上海理工大学光电信息与计算机工程学院上海200093

通过对环形线圈磁感应强度的电磁场分析,设计实现符合ISO 14443国际标准的射频IC卡读写器天线.根据实际需要将国民技术2.4GHz微波段射频偶极子天线放置于13.56MHz射频天线中,整合成双模射频IC卡读写器天线,为公共交通卡和RF-SIM卡手机... 详细信息

通过对环形线圈磁感应强度的电磁场分析,设计实现符合ISO 14443国际标准的射频IC卡读写器天线.根据实际需要将国民技术2.4GHz微波段射频偶极子天线放置于13.56MHz射频天线中,整合成双模射频IC卡读写器天线,为公共交通卡和RF-SIM卡手机支付业务提供支持.

关键词： RF-SIM 13.56MHz射频IC卡国民技术2.4GHz ISO 14443

Relevant Factors of Estrogen Changes of Myopia in Adolescent Females

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Chinese Medical Journal 2015年第5期128卷 659-663页

作者： Juan-Fen Gong Hong-Li Xie xin-jie mao Xue-Bo Zhu Zuo-Kai Xie Hai-Hong Yang Yang Gao Xiao-Feng Jin Yu Pan Fen Zhou The First Clinical Medical College of Wenzhou Medical University Zhejiang 325035 China Zhejiang Key Laboratory of Epidemiology and Health Statistics The First Clinical Medical College of Wenzhou Medical University Zhejiang 325035 China The Eye Hospital of Wenzhou Medical University Zhejiang 325035 China The Institute of Public Policy and Social Development Wenzhou Medical University Zhejiang 325035 China The Second Affiliated Hospital of Wenzhou Medical University Zhejiang 325035 China

Background：Gender is one of the risk factors accounting for the high prevalence of adolescent *** research results have shown that myopia incidence of female is higher than that of *** study aimed to analyze the correlation between ocular parameters and serum estrogen level and to investigate the vision changes along with estrogen change in menstrual cycle of adolescent ***：A total of 120 young females aged between 15 and 16 years,diagnosed with myopia were *** lens,cylindrical lens,axis,interpupillary distance （IPD）,and vision in each tested eye of the same subject were measured by automatic optometry and comprehensive optometry,with repetition of all measurements in the menstrual cycle of the 2nd or 3rd days,14th days,and 282 days,*** estradiol （E2） levels were assayed by chemiluminescence immunoassay at the same three times points of the menstrual cycle mentioned ***：In young females with myopia,the spherical lens showed a statistically significant difference among all different time in menstrual cycle （all P 〈 0.0001）.The cylindrical lens,axis,and IPD were changed significantly during the menstrual cycle （P 〈 0.05）.The vision of the three different time points in menstrual cycle had a significant difference （χ^2 =6.35,P =0.042）.The vision during the 14th and 28th day was higher compared to that on the 2nd or 3rd days （P =0.021）.Serum E2 levels were significantly different at different time points in menstrual cycle （P 〈 0.05）.E2 levels reached its maximum value on the 142 day and the minimum value on the 2nd or 3rd ***：In adolescent females,the spherical lens and other related ocular parameters vary sensitively with different levels of E2 in menstrual *** in late menstrual stage is significantly higher than that in premenstrual stage.

关键词： Adolescent Female Estrogen Menstrual Cycle Myopia

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人眼角膜散光矫正的点扩散函数分析表达

中华眼科杂志 2008年第7期44卷 609-614页

作者：姜珺毛欣杰金成鹏吕帆温州医学院附属眼视光医院 325027

目的探讨人眼点扩散函数（PSF）分析系统表达角膜散光眼的视网膜成像特性的可行性及角膜散光在不同矫正方式下的光学成像特征。方法前瞻性随机对照研究。利用PSF分析系统（PSF-1000）检查和评估26例近视散光患者（年龄18—28岁，球镜度... 详细信息

目的探讨人眼点扩散函数（PSF）分析系统表达角膜散光眼的视网膜成像特性的可行性及角膜散光在不同矫正方式下的光学成像特征。方法前瞻性随机对照研究。利用PSF分析系统（PSF-1000）检查和评估26例近视散光患者（年龄18—28岁，球镜度数-3．00～-6．00DS，散光度数-0．75～-3．00DC）在配戴框架眼镜、散光软性角膜接触镜（TSCL）和透氧性硬性角膜接触镜（RGPCL）3种全矫状态下的视网膜成像质量，采用26只眼屈光介质调制解调函数（MTF）曲线中的12个点（即分别等同于对数视力表4．0—5．1的12个点）进行比较和统计学分析。设置中度近视无散光者26例为对照组。左右眼MTF值比较使用配对样本t检验，与对照组的比较使用独立样本t检验，3种矫正方式的差异用单因素方差分析，P〈0．05时再进行配对样本t检验。以P〈0．05为差异有统计学意义。结果左右眼的MTF表达具有镜像对称性。与对照组比较，瞳孔直径3．0mm时，在低空间频率无差异，在中、高频空间频率差异有统计学意义（t值范围：-2．237～-5．421，P〈0．05）；瞳孔直径6．0mm时，在12个空间频率差异均有统计学意义（t值范围：-2．893～-9．577，P〈0．01）。3种矫正方式在模拟3．0和6．0mm瞳孔直径下MTF值差异均有统计学意义。3．0mm瞳孔时，除了3．00、3．78、4．78、30．00和37．80周／度5个空间频率外，其余空间频率RGPCL和框架眼镜的MTF值高于TSCL（F值范围：3．229—4．123，P〈0．05）。6．01／mm瞳孔直径下，12个空间频率的3种矫正方式差异均有统计学意义（F值范围：5．609—9．610，P〈0．05），RGPCL的MTF值较高。同一矫正状态下，3．0mm瞳孔直径下的MTF值均高于6．0mm瞳孔直径下的MTF值。结论PSF分析方法能综合表达像差、衍射和散射对视网膜成像质量的影响，RGPCL所产生的泪液镜不仅矫正角膜散光，同时可改善眼的衍射、散射和其他像差效应，从而获得相对较好的成像质量。

关键词：散光检眼镜检查接触镜似然函数

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视觉矫正质量评价研究

中华眼科杂志 2003年第6期39卷 325-327页

作者：瞿佳吕帆毛欣杰毛崇溶温州医学院眼视光学院 325003

目的　探讨视敏度和对比敏感度函数与视网膜光学成像质量的关系 ,评价各种屈光矫正方法获得的视觉质量。方法　 2 3例近视眼患者 (4 1只眼 )近视度数范围为 - 1 2 5D～ - 9 2 5D ,散光度数 0 0 5 )。在低频率点 (1 5及 3 0cpd) ,3种方... 详细信息

目的　探讨视敏度和对比敏感度函数与视网膜光学成像质量的关系 ,评价各种屈光矫正方法获得的视觉质量。方法　 2 3例近视眼患者 (4 1只眼 )近视度数范围为 - 1 2 5D～ - 9 2 5D ,散光度数 0 0 5 )。在低频率点 (1 5及 3 0cpd) ,3种方式的对比敏感度函数差异无显著意义 ,在高频率点 (6 0、12 0及 18 0cpd)RGP对比敏感度函数曲线明显高于SCL和SP。结论　视力对比敏感度函数可以较好的表达矫正的视网膜光学成像质量 ;RGP相对于SCL及SP而言 ,可提供较好的视觉质量。

关键词：视觉矫正方法近视视敏度眼镜视力检查

适应双面复合设计渐进多焦点镜片的过程中视觉功能的变化

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眼科 2011年第3期20卷 176-181页

作者：徐良黄海笑毛欣杰温州医学院附属眼视光医院 325000

目的通过与前表面设计渐进多焦点镜片(progressive addition lenses,PAL)的比较,研究老视患者配戴双面复合设计PAL在适应过程中视功能的变化。设计病例对照研究。研究对象老视患者16例,年龄(57.9±7.66)岁,等效球镜为(-1.06±3.33)D,近... 详细信息

目的通过与前表面设计渐进多焦点镜片(progressive addition lenses,PAL)的比较,研究老视患者配戴双面复合设计PAL在适应过程中视功能的变化。设计病例对照研究。研究对象老视患者16例,年龄(57.9±7.66)岁,等效球镜为(-1.06±3.33)D,近附加(+1.97±0.34)D。方法利用随机表将受试者分为两组,一组单盲先后给予全天配戴前表面设计和双面复合设计两种PAL各4周,另一组配戴顺序相反,于每副镜片初戴和配戴后第4周末进行戴镜状态下双眼4 m和40 cm高低对比度视力(100%、10%),双眼64 cm和40 cm清晰阅读范围及64 cm阅读速度的检测。对两次检测的差值采用两阶段交叉的方差分析。主要指标对比度视力,清晰阅读范围和阅读速度。结果配戴双面复合设计PAL适应前后中(64 cm)、近(40 cm)距离视功能参数变化较前表面设计有明显不同:(1)清晰阅读范围变化值:中距离时,双面复合设计组(2.969±3.668)cm(均值>0)较前表面设计组(-5.118±5.190 cm,均值0)较前表面设计组(-6.821±4.453 cm,均值0)较前表面设计组(-0.8375±1.2178个/秒,均值0.05)。结论配戴双面复合设计PAL适应前后在远近对比度视力变化与前表面设计PAL相同的情况下,提供渐宽的中近距离清晰阅读范围和渐快的中距离阅读速度,更加符合老视配戴者的视觉期望。

关键词：渐进多焦点镜片/双面复合设计老视高低对比度视力阅读速度清晰范围