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实现了前向两波长泵浦及3波长泵浦拉曼光纤放大器（RFA）.实验中所用的信号为符合ITU T建议的C波段20信道波分复用信号,波长为1537.377～1560.605nm,信号传输距离分别为100和75km.其中,3波长泵浦的增益波动

以一维 EQC码为例 ,研究了“不同时片不同波长”的二维码字结构的特点 ,分析了实现这种二维码字编码的光纤光栅编解码技术及其特点 ,并叙述了实现这种 OCDMA系统的星形拓扑结构

以光纤光栅滤波器的调谐为例 ,研究了 6种以应力拉伸或压缩为手段的光纤光栅的调谐方法 ,分析了它们的基本原理 ,并对它们的优缺点进行了比较 .

通过数值模拟研究了 1 6× 1 0 Gbit/s高速通信系统中非线性效应对系统误码率的影响 .模拟结果表明 :G.6 5 2光纤中存在的 SPM和 XPM非线性效应使得系统误码率随入纤光功率的增大呈现多级变化 ;入纤光功率的取值范围应为 9d Bm≤ Pin ≤ 1 6 d Bm.这些研究结论具有实用价值 .

研究了光正交码、EQC码和素数码与频率相结合构成的单跳频及多跳频二维地址码 ,并对它们的容量与采用波分复用系统时的容量进行了比较 ,得到了比采用跳频地址码容量更大的结论 .

分布拉曼放大器（DRA）的增益轮廓平坦度是衡量放大器性能的一个重要指标。文章通过实验验证了泵浦方式及入射信号功率对增益轮廓的重要影响作用。实验采用20信道符合ITU-T建议的波分复用（WDM）信号,波长从1537.377（信道1）～1560.605nm（信道20）,每一信道用2.5Gbit/s、码长27-1的非归零码通过电吸收调制器（EA）进行外调制。实验结果对分布拉曼放大器的增益轮廓平坦优化具有实际参考价值。

设计了利用啁啾光纤光栅（CFG）对10Gbit/s光信号进行色散补偿的仿真模拟系统,该模拟系统研究了5种不同的色散补偿方案对系统误码率的影响,选出了最佳的一种补偿方案.模拟研究了入纤光功率对系统误码率的影响,结论是在保持光探测器接收功率不变的条件下,入纤光功率越高,误码率越大.对于最佳色散补偿方案,入纤光功率为6dBm时既能保证较高的传输功率又有较好的误码性能.

Copyright of Electromachining & Mould is the property of Electromachining & Mould Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Science & Technology of Cereals, Oils & Foods is the property of Science & Technology of Cereals, Oils & Foods Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In view of the problems of large volume, high cost and complex structure of the existing multilevel inverter topology, a 13 level inverter based on switched capacitor is proposed. The proposed topology is composed of a DC input power supply, 3 capacitors and 14 switching devices, which realizes a 13 level output with 6 times boost. The proposed topology has lower cost and smaller volume, reduces the harmonic content of the system output, and realizes the inverter without H - bridge to reduce the voltage stress of the switch tube. The proposed inverter can achieve capacitor voltage self - balancing without any auxiliary method, which simplifies the complexity of control. The superiority of the proposed topology is verified by comparison with other traditional multilevel inverters. Simulation and experimental results verification on the simulation and prototype platform prove that the inverter has good performance in both steady and dynamic conditions. [ABSTRACT FROM AUTHOR]

Copyright of Urban Mass Transit is the property of Urban Mass Transit Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Copyright of Power Generation Technology is the property of Power Generation Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of University Chemistry is the property of Peking University, College of Chemistry & Molecular Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Technology Economics is the property of Chinese Society of Technology Economics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Copyright of Chinese Journal of Immunology is the property of Medical Periodical Society of Jilin and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Chongqing University of Technology (Natural Science) is the property of Chongqing University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective To summarize the clinical experiences of managing cervical lymphatic malformation with airway obstruction ( CLMAO) from prenatal assessments to postnatal interventions. Methods Retrospective analysis was conducted for clinical data of 22 hospitalized CLMAO infants from July 2015 to March 2023. Nine cases were born at our hospital while another 13 infants were transferred from other hospitals. They were assigned into two groups of early surgical treatment ( n = 6) and protocol treatment (n = 16 ). Fetal assessments, intrapartum managements and postnatal interventions were recorded. Surgical complications, duration of mechanical ventilation, length of hospital stay and other prognostic factors were compared between two groups. Results Nine infants born at our hospital were examined by prenatal magnetic resonance imaging( MRI) for assessing tracheoescphageal displacement index( TEDI) or amniotic fluid volume. Eight infants had TEDI> 12 mm or polyhydramnios. Ex-utero intrapartum treatment( EXIT) was offered for postnatal dyspnea. One case of TEDI≤ 12 mm and normal anmiotic fluid volume had dyspnea after umbilical cord clamping and underwent tracheal intubation. The accuracy of prenatal assessment for airway obstruction was 88. 9% ( 8/9). Three cases were operated in protocol treatment group. As compared with early treatment group, no significant inter-group differences existed in proportion of tracheostomy, duration of mechanical ventilation or length of hospital stay. During a follow-up period of ( 6 - 39) months, there was no significant difference in cure rate or improvement rate. Conclusion Fetuses with suspected CLMAO should be evaluated for TEDI and amniotic fluid volume. As compared with early surgery, programmed therapy may obtain comparable outcomes. It offers a novel therapeutic option for CLMAO. [ABSTRACT FROM AUTHOR]

Copyright of Modern Food Science & Technology is the property of Editorial Office of Modern Food Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Tunnel Construction / Suidao Jianshe (Zhong-Yingwen Ban) is the property of Tunnel Construction Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Copyright of Modern Food Science & Technology is the property of Editorial Office of Modern Food Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Science & Technology of Cereals, Oils & Foods is the property of Science & Technology of Cereals, Oils & Foods Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Science & Technology of Cereals, Oils & Foods is the property of Science & Technology of Cereals, Oils & Foods Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Power Generation Technology is the property of Power Generation Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Metal Working (1674-165X) is the property of Metal Working Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

针对或/符合代数系统中电路设计与化简的要求，提出了一种全新的图形表示方法——CRM分解图，给出了其特点和性质，并作了相应证明.此外，文中还讨论了对CRM分解图进行对称函数检测的方法，并以实例加以说明.本文的讨论揭示了 CRM分解图的内在规律，有助于开拓CRM分解图的应用领域，可以用来指导超大规模集成电路的设计和化简，使电路实现较传统设计更简单、更有效.

This study aims to explore the current situation of the regional distribution and fertility of soil in Jinggang pomelo planting area in Jiangxi Province. The topsoil（0~20 cm），subtopsoil（20~40 cm）and subsoil（40~60 cm）were collected from 110 main orchards of Jinggang pomelo in Jiangxi Province. The study carried out a systematic analysis of 12 soil fertility indexes including soil pH，organic matter and nutrient content using the ArcGIS technology，correlation analysis，and principal component analysis. The results showed that pH and contents of organic matter，alkali hydrolyzed nitrogen，available phosphorus，available potassium，available zinc，and exchangeable magnesium in the topsoil of the orchard were 4.00~7.38，7.85~32.71 g·kg-1 ，45.50~318.50 mg·kg-1 ，1.99~146.11 mg·kg-1 ，26.96~306.08mg·kg-1 ，0.36~16.47 mg·kg-1 ，and 15.00~219.63 mg·kg-1 ，respectively. The contents of available copper and exchangeable calcium were lower than 7.91 mg·kg-1 and 658.88 mg·kg-1 ，respectively. Soil fertility index decreased with the increase in soil depth. Overall，the pH of topsoil was higher in the middle of the planting area and lower around，while the content of available phosphorus showed an opposite trend. The content of organic matter of topsoil in the planting area was higher in the west and lower in the east，and the content of trace elements was less in the south than that in the north. Correlation analysis showed that there was a significantly positive correlation between topsoil pH and exchangeable magnesium content，and a significantly positive correlation between exchangeable magnesium content and exchangeable calcium，available zinc，total phosphorus，and available potassium. Principal component analysis showed that the contents of soil exchangeable calcium，exchangeable magnesium，alkali hydrolyzed nitrogen，and available zinc were the dominant factors influencing soil fertility variation in the planting area. The fertility and regional distribution of orchard soil in Jinggang pomelo planting area in Jiangxi Province were quite different. Improving the acid soil，supplementing medium trace elements are conducive to upgrading soil fertility. [ABSTRACT FROM AUTHOR]

Using solid - state physics theories and methods, the quantum capacitance of single-layer graphene and the variation of its temperature stability with temperature and voltage are studied, and the influence of atomic anharmonic vibration on it is discussed. The results show that the quantum capacitance and temperature stability coefficient of single-layer graphene both change nonlinearly with increasing temperature when the voltage is constant. The quantum capacitance increases with increasing temperature when the voltage is less than 2. 3 V. The stability coefficient slowly changes to quickly increases with increasing temperature. The quantum capacitance increases and then decreases with increasing temperature when the voltage is higher than 2. 3 V, and its temperature stability coefficient changes slowly to quickly with increasing temperature. When the temperature is constant, the quantum capacitance changes only when the voltage value is within the range of 0. 4 to 2. 8 V, and when the voltage is greater than 2.8 V, the quantum capacitance rapidly decreases and tends to zero. Compared with the simple harmonic approximation, the anharmonic term will increase the graphene quantum capacitance, and the higher the temperature, the greater the difference between the two, and the more significant the anharmonic effect. When the temperature is 300 K, The anharmonic quantum capacitance is 0. 33% larger than the harmonic approximation value, and when the temperature is 1 000 K, the difference increases to 1. 47%. When the voltage is between 1. 5 and 1. 8 V and the temperature is lower than 800 K, the temperature stability coefficient of the graphene quantum capacitor is the smallest and does not change with temperature, and the temperature stability of the energy storage performance is the best. The anharmonic term will increase the thermal stability coefficient of its quantum capacitor compared to the harmonic approximation, and the increase is related to the temperature, when the temperature is 400 K, the thermal stability coefficient of the quantum capacitor will in- crease by 67. 47%, while it increases by 22. 36% when the temperature is 1 000 K. The quantum capacitance result obtained in this paper is not only close to the result of the literature, but also shows the law and the analytical formula of quantum capacitance and its temperature stability coefficient with temperature, this has reference value for the application of graphene in the energy storage performance of supercapacitors. [ABSTRACT FROM AUTHOR]

Copyright of Asian Journals of Ecotoxicology is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Copyright of Oil Drilling & Production Technology / Shiyou Zuancai Gongyi is the property of Shiyou Zuancai Gongyi Bianjibu and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)