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催产素的Blog
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作者 朱奕萱 王青彤 +2 位作者 李瑾 陈林 赵军龙 《大学化学》 CAS 2024年第9期134-140,共7页
借用拟人化、第一人称的手法,以Blog的形式对肽类激素催产素从基本概况、研究历史、功能作用等方面进行简要介绍,并与相关物质进行类比分析,用生动有趣的语言让人们对催产素形成初步的认识。
关键词 催产素 功能
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Spatial pattern and drivers of urbanization in China's mid-level developing urban agglomeration:A case study of Chang-Zhu-Tan 被引量:9
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作者 Yanhua He Yi Lin +2 位作者 Guohua Zhou yixuan zhu Kai Tang 《Regional Sustainability》 2021年第1期83-97,共15页
Urban agglomeration has become the main form of regional spatial organization in China.While most of the existing studies of urban agglomeration in China have focused on the eastern coastal areas,urban agglomeration w... Urban agglomeration has become the main form of regional spatial organization in China.While most of the existing studies of urban agglomeration in China have focused on the eastern coastal areas,urban agglomeration with mid-level development in the rest of the country has been overlooke1.To better understand the urbanization process of the mid-level developing urban agglomeration,this study investigated the clustering pattern and the drivers of both urban population and firm dynamics during 2005-2015 in the Changsha-Zhuzhou-Xiangtan(Chang-Zhu-Tan)urban agglomeration of China using the methods ofkernel density estimation and geographic detection.Our results show that centralization was obvious,although decentralization also occurred in Chang-Zhu-Tan,and that the spatial agglomeration was promoted by several factors,such as administrative resources,location advantage,labor cost,and consumption capacity.Some problems hindering the development of this region were also discovered:administrative resources played a critical role in urbanization because small towns and villages did not receive enough attention,and the effect of local policy was not as beneficial as expected.These findings partly explain the relatively slow development of mid-level developing urban agglomerations and have important implications for promoting healthier urbanization. 展开更多
关键词 URBANIZATION Spatial pattern Urban agglomeration Firm clustering Driving mechanism China
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Particle Filter Object Tracking Algorithm Based on Sparse Representation and Nonlinear Resampling 被引量:3
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作者 Zheyi Fan Shuqin Weng +2 位作者 Jiao Jiang yixuan zhu Zhiwen Liu 《Journal of Beijing Institute of Technology》 EI CAS 2018年第1期51-57,共7页
Object tracking with abrupt motion is an important research topic and has attracted wide attention.To obtain accurate tracking results,an improved particle filter tracking algorithm based on sparse representation and ... Object tracking with abrupt motion is an important research topic and has attracted wide attention.To obtain accurate tracking results,an improved particle filter tracking algorithm based on sparse representation and nonlinear resampling is proposed in this paper. First,the sparse representation is used to compute particle weights by considering the fact that the weights are sparse when the object moves abruptly,so the potential object region can be predicted more precisely. Then,a nonlinear resampling process is proposed by utilizing the nonlinear sorting strategy,which can solve the problem of particle diversity impoverishment caused by traditional resampling methods. Experimental results based on videos containing objects with various abrupt motions have demonstrated the effectiveness of the proposed algorithm. 展开更多
关键词 object tracking abrupt motion particle filter sparse representation nonlinear resampling
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Very long wave infrared quantum cascade detector based on modular band structure
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作者 Kai Guo Yu Chen +7 位作者 yixuan zhu Kun Li Shenqiang Zhai Fengqi Liu Jilong Tang Xiaohua Wang Zhipeng Wei Junqi Liu 《Chinese Optics Letters》 SCIE EI CAS CSCD 2024年第8期119-123,共5页
The optoelectronic performance of quantum cascade detectors(QCDs)is highly sensitive to the design of the energy level structure,leading to the inability of a single structure to achieve broad wavelength tuning.To add... The optoelectronic performance of quantum cascade detectors(QCDs)is highly sensitive to the design of the energy level structure,leading to the inability of a single structure to achieve broad wavelength tuning.To address this issue,we propose and demonstrate a modular concept for very long wave infrared(VLWIR)QCDs based on a miniband diagonal transition scheme.The modular design makes the wavelength tuning only need to be adjusted for the absorption quantum well module rather than for the whole active region.Theoretical simulation shows that the wavelength tuning range is 39.6 meV(~14–30μm).To prove the feasibility of the scheme,three samples with different absorption well widths were fabricated and characterized.At 10 K,the response wavelengths of the three QCDs are 14,16,and 18μm,respectively,corresponding to responsivities and detectivities exceeding 2 mA/W and 1×10^(10)Jones. 展开更多
关键词 quantum cascade detector very long wave infrared modular band structure miniband diagonal transition wide tuning range
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Mode-switchable dual-color infrared quantum cascade detector
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作者 yixuan zhu SHENQIANG ZHAI +7 位作者 KUN LI KAI GUO QIANGQIANG GUO JINCHUAN ZHANG SHUMAN LIU LIJUN WANG FENGQI LIU JUNQI LIU 《Photonics Research》 SCIE EI CAS CSCD 2024年第2期253-259,共7页
In this paper,a patch-antenna-array enhanced quantum cascade detector with freely switchable operating modes among mid-wave,long-wave,and dual-color was proposed and discussed.The dual-color absorption occurs in a sin... In this paper,a patch-antenna-array enhanced quantum cascade detector with freely switchable operating modes among mid-wave,long-wave,and dual-color was proposed and discussed.The dual-color absorption occurs in a single active region through an optimized coupled miniband diagonal-transition subbands arrangement,and a successful separation of the operation regimes was realized by two nested antenna arrays with different patch sizes up to room temperature.At 77 K,the 5.7-μm channel achieved a peak responsivity of 34.6 mA/W and exhibited a detectivity of 2.0×10^(10)Jones,while the 10.0-μm channel achieved a peak responsivity of 87.5 mA/W,giving a detectivity of 5.0×10^(10)Jones.Under a polarization modulation of the incident light,the minimum cross talk of the mid-wave and the long-wave operating modes was 1:22.5 and 1:7.6,respectively.This demonstration opens a new prospect for multicolor infrared imaging chip integration technology. 展开更多
关键词 antenna POLARIZATION quantum
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Room-temperature continuous-wave InP-based 2.01 μm microcavity lasers in whispering-gallery modes with InGaAsSb quantum well
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作者 郭强强 张锦川 +8 位作者 朱怡璇 高旭 陆全勇 卓宁 翟慎强 刘俊岐 王利军 刘舒曼 刘峰奇 《Chinese Optics Letters》 SCIE EI CAS CSCD 2023年第4期65-68,共4页
We demonstrated an electrically pumped InP-based microcavity laser operating in continuous-wave mode.The active region is designed with antimony surfactants to enhance the gain at 2 μm,and a selective electrical isol... We demonstrated an electrically pumped InP-based microcavity laser operating in continuous-wave mode.The active region is designed with antimony surfactants to enhance the gain at 2 μm,and a selective electrical isolation scheme is used to secure continuous-wave operation for the microcavity laser at room temperature.The lasers were fabricated as a notched elliptical resonator,resulting in a highly unidirectional far-field profile with an in-plane beam divergence of less than 2°.Single-mode emission was obtained over the entire dynamic range,and the laser frequencies were tuned linearly with the pumping current.Overall,these directional lasers pave the way for portable and highly integrated on-chip sensing applications. 展开更多
关键词 whispering-gallery mode continuous-wave operation electrical isolation directional emission
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Current status and future directions of the Tibetan Plateau ecosystem research 被引量:1
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作者 Yangjian Zhang yixuan zhu +1 位作者 Junxiang Li Yao Chen 《Science Bulletin》 SCIE EI CAS CSCD 2019年第7期428-430,共3页
The Tibetan Plateau (TP) encompasses Xizang and Qinghai and parts of northern Yunnan and Sichuan provinces, with a total area of circa 2.6 millions km2. The 2013 satellite data showed that grasslands, forests, wetland... The Tibetan Plateau (TP) encompasses Xizang and Qinghai and parts of northern Yunnan and Sichuan provinces, with a total area of circa 2.6 millions km2. The 2013 satellite data showed that grasslands, forests, wetlands, agricultural lands, and deserts account for 60%, 7.7%, 1.4%, 0.3%, and 30%, respectively, of total TP land (1)Due to its existence in dry, high altitude and cold environments, the TP ecosystem is extremely vulnerable to global climate change and studies on the TP ecosystem can be utilized as a pre-warning for other ecosystems. 展开更多
关键词 Current status and future DIRECTIONS of the TIBETAN PLATEAU ECOSYSTEM research TP
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Defect engineering of BCZT-based piezoelectric ceramics with high piezoelectric properties 被引量:1
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作者 Xinjian WANG Yu HUAN +6 位作者 yixuan zhu Peng ZHANG Wenlong YANG Peng LI Tao WEI Longtu LI Xiaohui WANG 《Journal of Advanced Ceramics》 SCIE EI CAS CSCD 2022年第1期184-195,共12页
The intrinsic conduction mechanism and optimal sintering atmosphere of(Ba_(0.85)Ca_(0.15))(Zr_(0.1)Ti_(0.9))O_(3)(BCZT)ceramics were regulated by Mn-doping element in this work.By Hall and impedance analysis,the undop... The intrinsic conduction mechanism and optimal sintering atmosphere of(Ba_(0.85)Ca_(0.15))(Zr_(0.1)Ti_(0.9))O_(3)(BCZT)ceramics were regulated by Mn-doping element in this work.By Hall and impedance analysis,the undoped BCZT ceramics exhibit a typical n-type conduction mechanism,and the electron concentration decreases with the increasing oxygen partial pressure.Therefore,the undoped ceramics exhibit best electrical properties(piezoelectrical constant<733=585 pC·N^(-1),electro-mechanical coupling factor k_(p)=56%)in O_(2).A handful of Mn-doping element would transfer the conduction mechanism from n-type into p-type.And the hole concentration reduces with the decreasing oxygen partial pressure for Mn-doped BCZT ceramics.Therefore,the Mn-doped ceramics sintered in N_(2)have the highest insulation resistance and best piezoelectric properties(d_(33)=505 pC·N^(-1),k_(p)=50%).The experimental results demonstrate that the Mn-doping element can effectively adjust the intrinsic conduction mechanism and then predict the optimal atmosphere. 展开更多
关键词 BCZT ceramics Mn-doping different sintering atmosphere p/n-type conduction mechanism defect engineering
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Gottfried Konecny:our best friend in photogrammetry and remote sensing of China 被引量:1
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作者 Deren Li yixuan zhu Lite Shi 《Geo-Spatial Information Science》 SCIE CSCD 2021年第1期5-7,I0002,共4页
Preface Lebenslauf Prof.Dr.-Ing.mult Gottfried Konecny is one of the most respected names in photogrammetry.He is an Honorary Member of International Society for Photogrammetry and Remote Sensing(ISPRS),Honorary Profe... Preface Lebenslauf Prof.Dr.-Ing.mult Gottfried Konecny is one of the most respected names in photogrammetry.He is an Honorary Member of International Society for Photogrammetry and Remote Sensing(ISPRS),Honorary Professor of Wuhan Technical University of Surveying and Mapping,and our best friend. 展开更多
关键词 gramme ISPRS REMOTE
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