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Optical transmitter module with hybrid integration of DFB laser diode and proton-exchanged LiNbO_(3)modulator chip

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Journal of Semiconductors 2022年第6期43卷 34-39页

作者： Xuyang Wang He jia junhui Li Yumei Guo Yu Liu State Key Laboratory on Integrated Optoelectronics Institution of SemiconductorsChinese Academy of SciencesBeijing 100083China University of Chinese Academy of Sciences Beijing 100049China Beijing Shiweitong Science&Technology Co. Ltd.Beijing 100176China

In this work,a hybrid integrated optical transmitter module was designed and fabricated.A proton-exchanged Mach–Zehnder lithium niobate(LiNbO_(3))modulator chip was chosen to enhance the output extinction ratio.A fiber was used to adjust the rotation of the polarization direction caused by the optical *** whole optical path structure,including the laser chip,lens,fiber,and modulator chip,was simulated to achieve high optical output *** a series of process improvements,a module with an output extinction ratio of 34 dB and a bandwidth of 20.5 GHz(from 2 GHz)was *** optical output efficiency of the whole module reached approximately 21%.The link performance of the module was also measured.

关键词： optical transmitter module hybrid integration DFB laser chip LiNbO3 modulator chip

松辽盆地北部青山口组富烃页岩形成环境与成因

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世界地质 2024年第1期43卷 19-36页

作者：付秀丽李军辉郑强崔坤宁王跃文贾琼蒙启安东北石油大学地球科学学院黑龙江大庆163318 大庆油田有限责任公司勘探开发研究院黑龙江大庆163712 多资源协同陆相页岩油绿色开采全国重点实验室黑龙江大庆163712 中国石油大庆油田有限责任公司黑龙江大庆163002

通过古地温、古地貌、沉积环境定量恢复及地质事件综合研究,分析青山口组富烃页岩形成环境及成因。结果表明,松辽盆地青山口组富烃页岩R_(o)介于0.75%~1.60%,游离烃含量高,介于(4~12)mg/g,形成于古地温梯度(50~70)℃/km的高温热盆背景;... 详细信息

通过古地温、古地貌、沉积环境定量恢复及地质事件综合研究,分析青山口组富烃页岩形成环境及成因。结果表明,松辽盆地青山口组富烃页岩R_(o)介于0.75%~1.60%,游离烃含量高,介于(4~12)mg/g,形成于古地温梯度(50~70)℃/km的高温热盆背景;在拉伸大地动力学及热沉降背景下形成了正断层密集断裂带控制的页岩层系,两凹一凸的古地貌为页岩形成演化提供富集场所;湖相温湿气候及岩浆热液为藻类繁殖成为厚层富烃页岩发育奠定物质基础;缺氧的半深湖—深湖还原—强还原环境有利于有机质埋藏。综合分析表明,构造、湖相沉积与古地温耦合作用奠定了富烃页岩的构造背景和热动力条件,温湿气候、缺氧环境及火山热液带来的营养物质是富烃页岩形成的重要原因。

关键词：富烃页岩古地温梯度构造演化火山活动沉积环境青山口组松辽盆地

Perovskite/silicon-based heterojunction tandem solar cells with 14.8%conversion efficiency via adopting ultrathin Au contact

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Journal of Semiconductors 2017年第1期38卷 60-65页

作者： Lin Fan Fengyou Wang junhui Liang Xin Yao jia Fang Dekun Zhang Changchun Wei Ying Zhao Xiaodan Zhang Institute of Photo-Electronic Thin Film Devices and Technology of Nankai University Key Laboratory of Photo-Electronic Thin Film Devices and TechnologyTianjin 300071China Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) Tianjin 300072China

A rising candidate for upgrading the performance of an established narrow-bandgap solar technology without adding much cost is to construct the tandem solar cells from a crystalline silicon bottom cell and a high open-circuit voltage top ***,we present a four-terminal tandem solar cell architecture consisting of a selffiltered planar architecture perovskite top cell and a silicon heterojunction bottom cell.A transparent ultrathin gold electrode has been used in perovskite solar cells to achieve a semi-transparent *** transparent ultrathin gold contact could provide a better electrical conductivity and optical reflectance-scattering to maintain the performance of the top cell compared with the traditional metal oxide *** four-terminal tandem solar cell yields an efficiency of 14.8%,with contributions of the top（8.98%）and the bottom cell（5.82%）,*** also point out that in terms of optical losses,the intermediate contact of self-filtered tandem architecture is the uppermost problem,which has been addressed in this communication,and the results show that reducing the parasitic light absorption and improving the long wavelength range transmittance without scarifying the electrical properties of the intermediate hole contact layer are the key issues towards further improving the efficiency of this architecture device.

关键词： lanar perovskite top cell silicon heterojunction bottom cell four-terminal tandem transparent ultra-thin gold electrode

Nitrogen Deposition and Its Spatial Pattern in Main Forest Ecosystems along North-South Transect of Eastern China

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Chinese Geographical Science 2014年第2期24卷 137-146页

作者： ZHAN Xiaoyun YU Guirui HE Nianpeng FANG Huajun jia Bingrui ZHOU Mei WANG Chuankuan ZHANG junhui ZHAO Guangdong WANG Silong LIU Yunfen YAN Junhua Synthesis Research Center of Chinese Ecosystem Research Network Key Laboratory of Ecosystem Network Observation and ModelingInstitute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences University of Chinese Academy of Sciences Institute of Botany Chinese Academy of Sciences College of Ecology and Environmental Science Inner Mongolia Agricultural University College of Forestry Northeast Forestry University Institute of Applied Ecology Chinese Academy of Sciences Institute of Forest Ecology Environment and Protection Chinese Academy of Forestry South China Botany Garden Chinese Academy of Sciences

A continuous three-year observation(from May 2008 to April 2011)was conducted to characterize the spatial variation of dissolved inorganic nitrogen(DIN)deposition at eight main forest ecosystems along the north-south transect of eastern China(NSTEC).The results show that both throughfall DIN deposition and bulk DIN deposition increase from north to south along the *** DIN deposition varies greatly from 2.7 kg N/(ha·yr)to 33.0 kg N/(ha·yr),with an average of 10.6 kg N/(ha·yr),and bulk DIN deposition ranges from 4.1 kg N/(ha·yr)to 25.4 kg N/(ha·yr),with an average of 9.8 kg N/(ha·yr).NH4+-N is the dominant form of DIN deposition at most sampling ***,the spatial variation of DIN deposition is controlled mainly by ***,in the northern part of the NSTEC,bulk DIN deposition is 17%higher than throughfall DIN deposition,whereas the trend is opposite in the southern part of the *** results demonstrate that DIN deposition would likely threaten the forest ecosystems along the NSTEC,compared with the critical loads(CL)of N deposition,and DIN deposition in this region is mostly controlled by agricultural activities rather than industrial activities or transportation.

关键词： forest ecosystem nitrogen deposition NH4+-N NO3-N eastern China

Changes in the relationship between species richness and belowground biomass among grassland types and along environmental gradients in Xinjiang, Northwest China

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Journal of Arid Land 2019年第6期11卷 855-865页

作者： YANG Yuling LI Minfei MA Jingjing CHENG junhui LIU Yunhua jia Hongtao LI Ning WU Hongqi SUN Zongjiu FAN Yanmin SHENG jiandong jiaNG Ping'an Xinjiang Key Laboratory of Soil and Plant Ecological Processes College of Grassland and Environmental SciencesXinjiang Agricultural UniversityUrumqi 830052China Xinjiang Institute of Ecology and Geography Chinese Academy of SciencesUrumqi 830011China

The association between biodiversity and belowground biomass(BGB) remains a central debate in *** this study, we compared the variations in species richness(SR) and BGB as well as their interaction in the top(0–20 cm), middle(20–50 cm) and deep(50–100 cm) soil depths among 8 grassland types(lowland meadow, temperate desert, temperate desert steppe, temperate steppe desert, temperate steppe, temperate meadow steppe, mountain meadow and alpine steppe) and along environmental gradients(elevation, energy condition(annual mean temperature(AMT) and potential evapotranspiration(PET)), and mean annual precipitation(MAP)) based on a 2011–2013 survey of 379 sites in Xinjiang, Northwest *** SR and BGB varied among the grassland *** alpine steppe had a medium level of SR but the highest BGB in the top soil depth, whereas the lowland meadow had the lowest SR but the highest BGB in the middle and deep soil *** SR and BGB in the different soil depths were tightly associated with elevation, MAP and energy condition;however, the particular forms of trends in SR and BGB depended on environmental factors and soil *** relationship between SR and BGB was unimodal in the top soil depth, but SR was positively related with BGB in the middle soil *** elevation, MAP, energy condition and SR had significant effects on BGB, the variations in BGB in the top soil depth were mostly determined by elevation, and those in the middle and deep soil depths were mainly affected by energy *** findings highlight the importance of environmental factors in the regulations of SR and BGB as well as their interaction in the grasslands in Xinjiang.

关键词： species richness belowground biomass unimodal pattern energy condition soil depths mean annual precipitation grasslands in Xinjiang

山海组团型城市发展突围之道——以宁德市城市能级提升优化为例

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华东地质 2024年第2期45卷 206-217页

作者：林丰增郭佳林韶恺缪文嘉彭博戚均慧王继龙哈尔滨工业大学建筑学院寒地城乡人居环境科学与技术工业和信息化部重点实验室黑龙江哈尔滨150006 宁德市人民政府福建宁德352101 宁德市自然资源局福建宁德352100 福建理工大学土木工程学院福建福州350118 中国地质调查局南京地质调查中心江苏南京210016 中国城市科学研究会联合创新研究所北京100835

城市能级提升代表了城市综合功能的完善,深入剖析城市能级限制因素是寻找城市发展突围之道的关键。宁德市本底特征是山海交融,随着经济实力逐渐提升、主导产业日益鲜明,主要面临城镇发展用地保障难度大、中心城区经济辐射较弱、产城融... 详细信息

城市能级提升代表了城市综合功能的完善,深入剖析城市能级限制因素是寻找城市发展突围之道的关键。宁德市本底特征是山海交融,随着经济实力逐渐提升、主导产业日益鲜明,主要面临城镇发展用地保障难度大、中心城区经济辐射较弱、产城融合发展程度滞后、核心圈层自然资源利用不足、生产性服务业发展较为滞后和消费外溢等限制因素。据此,明确了土地资源高效利用与配置、主导产业快速发展、城市服务能力提升和山海资源转化四条城市发展赋能路径,并结合实际,提出了加快优质资源要素集聚、腾挪低效产业、促进环湾面海集聚发展、塑造特色城市名片、壮大生产性服务业和完善基础公共服务设施等具体对策,旨在全方位推进高质量发展,奋力谱写全面建设社会主义现代化国家的“宁德篇章”。

关键词：宁德市国土空间规划山海组团城市能级发展路径与对策

Effect of external surface of HZSM-5 zeolite on product distribution in the conversion of methanol to hydrocarbons

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Journal of Energy Chemistry 2014年第6期23卷 771-780页

作者： junhui Li Yanan Wang Wenzhi jia Zhiwen Xi Huanhui Chen Zhirong Zhu Zhonghua Hu Department of Chemistry Tongji University

The external surface of HZSM-5 zeolite was passivated by liquid siliceous deposition and by acidic sites poisoning with lepidine, respectively. Then methanol-to-hydrocarbons （MTH） reaction was investigated over the above as-prepared catalysts and the dissoluble coke on these used catalysts was analyzed by GC-MS, to study the role of the external surface of HZSM-5 in the catalytic reaction. Comparison with the experi- mental results based on parent ZSM-5 showed that the product distribution of MTH reaction was obviously influenced by the external surface. Evidences were listed as follows：（1） the final product on parent HZSM-5 showed higher aromatic selectivity, lower olefin selectivity, lower ra- tio of C2/C3＋ aliphatics and higher ratio of C3/C4＋ aliphatics than the reaction mixture produced by the sole catalysis of acidic sites in HZSM-5 channel; （2） a little of pentamethylbenzene and hexamethylbenzene in the product on parent HZSM-5, was produced via multi-methylation of methylbenzene on the external surface. The above conclusion may also be suitable for MTH reaction over other zeolites with 10-ring channel.

关键词： methanol-to-hydrocarbons product distribution HZSM-5 external surface acidic sites

周边离焦框架眼镜与角膜塑形镜对儿童近视进展控制效果及视力相关生存质量的影响

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国际眼科杂志 2024年第10期24卷 1629-1633页

作者：周海涛佐明龙郎佳沈婷吕晓艳张军辉王媛媛中国浙江省湖州市中心医院眼科 313000 湖州师范学院浙江省湖州市313000

目的:探讨周边离焦框架眼镜与角膜塑形镜(OK镜)对儿童近视进展控制效果及视力相关生存质量的影响。方法:前瞻性研究。选取2021-01/2022-01在湖州市中心医院眼科首次诊断为近视的患儿237例,根据不同矫正方式分为:周边离焦框架眼镜组105例... 详细信息

目的:探讨周边离焦框架眼镜与角膜塑形镜(OK镜)对儿童近视进展控制效果及视力相关生存质量的影响。方法:前瞻性研究。选取2021-01/2022-01在湖州市中心医院眼科首次诊断为近视的患儿237例,根据不同矫正方式分为:周边离焦框架眼镜组105例105眼,OK镜组132例132眼(所有入组儿童眼部参数均选取右眼数据纳入统计)。使用中小学生视力相关生存质量量表对两组近视患儿进行随访调查,并记录首次就诊及随访1 a时儿童最佳矫正视力(BCVA)、等效球镜度数、眼轴(AL)数据。结果:戴镜1 a后,两组患儿等效球镜度数及AL均增长,但两组间比较均无差异(P>0.05)。周边离焦框架眼镜组患儿等效球镜度数变化量和AL变化量大于OK组(均P=0.001)。戴镜1 a后,两组患儿在中小学生视力相关生存质量量表问卷中,周边离焦框架眼镜组情感维度得分高于OK镜组(P<0.05)。OK镜组患儿情感维度得分变化量大于周边离焦框架眼镜组(P<0.05)。结论:OK镜控制儿童近视进展效果优于周边离焦框架眼镜。两种矫正方式均可显著提升近视患儿视力相关生存质量,OK镜在改善儿童视力相关生存质量量表情感维度上优于周边离焦框架眼镜。

关键词：角膜塑形镜周边离焦框架眼镜眼轴等效球镜度数视力相关生存质量

Visualizing light-to-electricity conversion process in InGaN/GaN multi-quantum wells with a p-n junction

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Chinese Physics B 2018年第9期27卷 157-161页

作者： Yangfeng Li Yang jiang Shen Yan Haiyan Wu junhui Die Caiwei Wang Ziguang Ma Lu Wang Haiqiang jia Wenxin Wang and Hong Chen Key Laboratory for Renewable Energy Beijing Key Laboratory for New Energy Materials and DevicesBeijing National Laboratory for Condensed Matter PhysicsInstitute of PhysicsChinese Academy of SciencesBeijing 1 O0190China University of Chinese Academy of Sciences Beijing 100049China

Absorption and carrier transport behavior plays an important role in the light-to-electricity conversion process, which is difficult to characterize. Here we develop a method to visualize such a conversion process in the InGaN/GaN multiquantum wells embedded in a p-n junction. Under non-resonant absorption conditions, a photocurrent was generated and the photoluminescence intensity decayed by more than 70% when the p-n junction out-circuit was switched from open to short. However, when the excitation photon energy decreased to the resonant absorption edge, the photocurrent dropped drastically and the photoluminescence under open and short circuit conditions showed similar intensity. These results indicate that the escaping of the photo-generated carriers from the quantum wells is closely related to the excitation photon energy.

关键词： multiple quantum wells p-n junction light-to-electricity photocurrent