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Solid Phase Synthesis of β-Carbolines

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Chinese Chemical Letters 2000年第11期11卷 955-956页

作者： Jing Xin ZHANG, xiao Chuan TAN, ping xie, xiao Tian LIANG Institute of Material Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050 Institute of Material Medica Chinese Academy of Medical Sciences Peking Union Medical College Beijing 100050 China

Synthesis of β-carbolines on solid phase using TCCA as the key reagent is developed.

关键词： Solid phase synthesis β-carbolines TCCA.

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Simultaneous polarization separation and switching for 100-Gbps DP-QPSK signals in backbone networks

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Chinese Physics B 2019年第2期28卷 299-305页

作者： Yu-Long Su Huan Feng Hui Hu Wei Wang Tao Duan Yi-Shan Wang Jin-Hai Si xiao-ping xie He-Ning Yang Xin-Ning Huang State Key Laboratory of Transient Optics and Photonics Xi'an Institute of Optics and Precision MechanicsChinese Academy of Sciences Key Laboratory for Physical Electronics and Devices of the Ministry of Education and Shaanxi Key Laboratory of Information Photonic Technique School of Electronic and Information EngineeringXi'an Jiaotong University University of Chinese Academy of Sciences

We propose a novel scheme of simultaneous polarization separation and switching, based on the orthogonallypolarized four-wave mixing(FWM) effect, for ultra-high-speed polarization multiplexing(Pol-MUX) fiber networks such as 100-Gbps and 400-Gbps backbone networks. We use theoretical and experimental analysis of the vector theory of FWM to successfully achieve polarization separation and all-optical switching by utilizing a 100-Gbps dual polarizationquadrature phase shift keying(DP-QPSK) signal and two orthogonally-polarized pumps. Both of the polarization-separated QPSK signals have clear constellation diagrams, with root mean square(RMS) error vector magnitudes(EVMs) of 14.32%and 14.11% respectively. The wavelengths of idlers can be created at 30 different wavelengths, which are consistent with International Telecommunication Union-Telecommunication(ITU-T) wavelengths, by flexibly changing the wavelength of the pump light. Moreover, the idlers that have distinct wavelengths have power distributed in a range from-10 dBm to-15 dBm, which can support error-free transmission. The power penaltyis 5 d B lower than that of back-to-back(BTB)signal for both the X-and Y-polarization components measured at a bit error ratio(BER) of 3.8×10^(-3). Our experimental results indicate that this scheme has promising applications in future backbone networks.

关键词： polarization separation and switching four-wave mixing orthogonal polarization 100-Gbps dual polarization-quadrature phase shift keying

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Experimental Study on Geometry Characteristics of Turbulent Premixed Flames for Natural Gas/Air Mixtures

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Journal of Thermal Science 2025年第1期34卷 268-282页

作者： ZHENG Weilin WANG Qijiao xiao Huahua CHEN xiaoxiao xie Fan ZENG Wen Liaoning Key Lab of Advanced Test Technology for Aerospace Propulsion System Shenyang Aerospace University State Key Laboratory of Fire Science University of science and Technology of China AVIC Shenyang Aircraft Design and Research Institute

In this study,focusing on the geometry characteristics of spherical expanding flame,the turbulent premixed flames of natural gas/air mixtures were investigated in a fan-stirred turbulent *** effects of initial temperature（T=300-400 K）,initial pressure（P=0.1-0.3 MPa）,turbulence intensity（u'=1.0-2.7 m/s）,oxygen volumetric percentage(φ（O2）=15%-21%) and carbon dioxide volumetric percentage(φ（CO2）=0-20%)were delved *** flame profile under the Cartesian coordinate system was derived from the schlieren images taken by the high-speed ***,from both macroscopic and microscopic perspectives,the influence of experimental conditions on the flame geometry characteristics was explored through flame front extraction,wavelet decomposition and network *** results demonstrate that for significant flame wrinkling,changes in species concentrations and turbulence intensity have more pronounced effects on the flame wrinkling *** wrinkling of the flame front maintains a certain degree of similarity,as evidenced by the locally concentrated distribution of the angles of the maximum fluctuation *** disturbance energy under large-scale（D6-D8） disturbances exhibits relatively high values with a similar trend,exerting a significant impact on the geometry characteristics of the flame *** peaks of correlation degree are scattered either with the decomposition scale or the development of flame radius,indicating no linear correlation between different detail ***,the probability distribution of node degrees in key wrinkled regions exhibits different trends with that of large-scale wrinkling and disturbance energy,especially with changes in initial *** occurs because the number of key wrinkles varies based on the perturbation's strength or the region's ***,an increase in the fluctuation frequency of the flame's local radius may not necessarily lead to an increase in the number of key folded regions.

关键词： fan-stirred turbulent combustor geometry characteristics large-scale wrinkling network topology wavelet decomposition

Device simulation of quasi-two-dimensional perovskite/silicon tandem solar cells towards 30%-efficiency

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Chinese Physics B 2022年第10期31卷 592-598页

作者： xiao-ping xie Qian-Yu Bai Gang Liu Peng Dong Da-Wei Liu Yu-Feng Ni Chen-Bo Liu He Xi Wei-Dong Zhu Da-Zheng Chen Chun-Fu Zhang Qinghai Huanghe Hydropower Development CO. LTD.Xining 810008China State Key Discipline Laboratory of Wide Band Gap Semiconductor Technology Xidian UniversityXi’an 710071China

Perovskite/silicon(Si) tandem solar cells have been recognized as the next-generation photovoltaic technology with efficiency over 30% and low cost. However, the intrinsic instability of traditional three-dimensional(3D) hybrid perovskite seriously hinders the lifetimes of tandem devices. In this work, the quasi-two-dimensional(2D)(BA)_(2)(MA)_(n-1)Pbn I_(3n+1)(n = 1, 2, 3, 4, 5)(where MA denotes methylammonium and BA represents butylammonium), with senior stability and wider bandgap, are first used as an absorber of semitransparent top perovskite solar cells(PSCs) to construct a fourterminal(4T) tandem devices with a bottom Si-heterojunction cell. The device model is established by Silvaco Atlas based on experimental parameters. Simulation results show that in the optimized tandem device, the top cell(n = 4) obtains a power conversion efficiency(PCE) of 17.39% and the Si bottom cell shows a PCE of 11.44%, thus an overall PCE of 28.83%. Furthermore, by introducing a 90-nm lithium fluoride(LiF) anti-reflection layer to reduce the surface reflection loss, the current density(J_(sc)) of the top cell is enhanced from 15.56 m A/cm^(2) to 17.09 m A/cm^(2), the corresponding PCE reaches 19.05%, and the tandem PCE increases to 30.58%. Simultaneously, in the cases of n = 3, 4, and 5, all the tandem PCEs exceed the limiting theoretical efficiency of Si cells. Therefore, the 4T quasi-2D perovskite/Si devices provide a more cost-effective tandem strategy and long-term stability solutions.

关键词： two-dimensional device simulation antireflection layers tandem solar cells

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COMPrompter: reconceptualized segment anything model with multiprompt network for camouflaged object detection

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Science China(Information Sciences) 2025年第1期68卷 189-203页

作者： xiaoqin ZHANG Zhenni YU Li ZHAO Deng-ping FAN Guobao xiao Zhejiang Province Key Laboratory of Intelligent Informatics for Safety and Emergency Wenzhou University Nankai International Advanced Research Institute (SHENZHEN FUTIAN) College of Computer Science Nankai University School of Computer Science and Technology Tongji University

We rethink the segment anything model(SAM) and propose a novel multiprompt network called COMPrompter for camouflaged object detection(COD). SAM has zero-shot generalization ability beyond other models and can provide an ideal framework for COD. Our network aims to enhance the single prompt strategy in SAM to a multiprompt strategy. To achieve this, we propose an edge gradient extraction module, which generates a mask containing gradient information regarding the boundaries of camouflaged objects. This gradient mask is then used as a novel boundary prompt, enhancing the segmentation process. Thereafter, we design a box-boundary mutual guidance module, which fosters more precise and comprehensive feature extraction via mutual guidance between a boundary prompt and a box prompt. This collaboration enhances the model's ability to accurately detect camouflaged objects. Moreover, we employ the discrete wavelet transform to extract high-frequency features from image embeddings. The high-frequency features serve as a supplementary component to the multiprompt ***, our COMPrompter guides the network to achieve enhanced segmentation results, thereby advancing the development of SAM in terms of COD. Experimental results across COD benchmarks demonstrate that COMPrompter achieves a cutting-edge performance, surpassing the current leading model by an average positive metric of 2.2% in COD10K. In the specific application of COD, the experimental results in polyp segmentation show that our model is superior to top-tier methods as well. The code will be made available at https://***/guobaoxiao/COMPrompter.

关键词： segment anything model camouflaged object detection boundary prompt

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Structural engineering of high-entropy alloys for advanced electrocatalytic reactions

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Tungsten 2025年第1期7卷 1-31页

作者： Qiao xie Ying-Jie Yu Hai-Jun Zhang Ya-ping Deng Wen Lei The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and Technology Department of Chemical Engineering Waterloo Institute for Sustainable Energy Waterloo Institute for Nanotechnology University of Waterloo

High-entropy alloys(HEAs) have emerged as promising candidates to replace traditional precious metal catalysts,owing to their unique chemical and physical *** review commences by revisiting the fundamental concepts of HEAs,including their synthesis methods and structural control strategies in *** underscores the critical role of meticulously manipulating both macroscopic and microscopic structures of the HEAs to optimize their catalytic performance.A deep understanding of the structure-activity relationship in HEAs across various configurations is pivotal in developing more effective *** review methodically encapsulates the research progress of structural control strategies for HEAs in achieving efficient energy conversion,with the aim of gaining a better understanding of the relationship between structure and *** review concludes by summarizing the current achievements and challenges,and suggestions for potential future directions of HEAs in the fields of energy conversion and environmental purification.

关键词： Electrocatalytic Energy conversion High-entropy alloys Structural modulation

Cholesterol regulates arterial constriction to angiotensin Ⅱ of simulated weightless rats

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Cholesterol regulates arterial constriction to angiotensin ...

Observation of topological charge transformations in acoustic vortex using passive periodic systems

第十二届全国营养科学大会

作者： Jun-Xiang Bao Zhong-Chao Wang Yao-ping Cheng Jin-Ma xiao-ping xie Yao-Ming Chang Department Aerospace Hygiene Fourth Military Medical University

Weightlessness or simulated weightlessness would induce functional adaptation of arteries eliciting postflight orthostatic intolerance, but the change of angiotensin Ⅱ(Ang Ⅱ) elicited vasoconstriction has never been *** are invaginations on cell membrane enriched of cholesterol and sphingolipids crucial for the contraction of vascular smooth muscle cells(VSMCs). We tried to postulate how the vasoconstriction to Ang Ⅱ was adapted by simulated weightlessness, the role of caveolae in the adaptation and whether cholesterol could regulates the effect. 4 wk hindlimb-unweighted(HU) rat was used to simulate the effect of weightlessness. Abdominal aorta(AA), thoracic aorta(TA) and carotid artery(CA) were isolated from control(CON) or HU rats, and then the vasoconstriction to Ang Ⅱ was measured by isometric force recording. Morphology of caveolae was explored by the method of transmission electron microscope(TEM). The binding of angiotensin Ⅱ type 1 receptor(AT1) and caveolin-1(cav-1), the structural protein of caveolae, was detected through coimmunoprecipitation and Western blot. We first found maximal developing force(Emax) of the Ang II elicited vasoconsitriction was decreased in AA, unchanged in TA and increased in CA after HU, while EC50 of the response was increased significantly in all the three arteries so did the extent of AT1 desensitization upon activation. Next, we found caveolae amount on VSMCs of AA, TA and CA was reduced by HU, while the protein content of cav-1 did not change. Ang II promoted the binding of AT1 and cav-1 which could be prevented significantly by HU in all the three arteries. Both the caveolae amount and the binding of AT1 and cav-1 could be recovered by pretreatment of cholesterol(10 m M, 1h). Correspondingly, EC50 of the response, as well as AT1 desensitization in the three arteries were also be reinstated on chol incubation. The result indicates modified caveolae on VSMCs interfere with the binding of AT1 and cav-1 facilitating

关键词： cholesterol caveolae vasoconstrictor reactivity angiotensin Ⅱ,vascular remodeling hindlimb unweighting

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 140-147页

作者： Di-Chao Chen xie Liu Changqing Xu Da-Jian Wu Ying Cheng xiao-Jun Liu School of Physics and Technology Nanjing Normal University Key Laboratory of Modern Acoustics School of Physics Nanjing University

Vortex transmutation utilizes a periodic system, which not only enables the alteration of the topological charge(TC) of unstable input vortices but also facilitates their transformation into stable structures. This approach is crucial for investigating the characteristics of vortices in various wave systems. Here, we achieve acoustic vortex TC transmutation by employing a welldesigned dual-structured plate external system(DPES). The interactions between the acoustic vortex and the finite-order discrete rotational symmetry lead to the transformation of its topological charge when complete rotational symmetry is broken to Nthorder discrete symmetry. Our results experimentally demonstrate the acoustic vortex TC transmutation based on passive artificial structures, enabling numerous applications in particle manipulation and information multiplexing as well as advancing our understanding and control over free-space acoustic vortices.

关键词： acoustic vortex topological charge transformation artificial structure

Dissipation-free approach for realizing non-Hermitian dynamics in a superconducting circuit

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Science China(Physics,Mechanics & Astronomy) 2025年

作者： Yi-Hao Kang Yang xiao Yu Wang Qi-ping Su Chui-ping Yang School of Physics Hangzhou Normal University Fujian Key Laboratory of Quantum Information and Quantum Optics Fuzhou University Department of Physics Fuzhou University

Non-Hermitian dynamics exhibits a wealth of surprising and potentially useful phenomena. However, it is typically realized by coupling a system with thermal reservoirs, which makes the system suffer from thermal fluctuations associated with the dissipation. Here, we propose a dissipation-free approach to realize non-Hermitian dynamics using a superconducting circuit composed of two resonators and a superconducting qutrit. The non-Hermiticity arises in the dynamical matrix for the evolution of the two resonators in the Heisenberg picture, via a photon-number non-conserved dynamics. The energy spectrum of the non-Hermitian dynamical matrix can be retrieved by measuring the state of the two resonators, and a phase transition of the energy spectrum can be observed by varying the control parameters. In the realization of the non-Hermitian dynamics, the dissipation of the system and the post-selection are not required. Thus, the approach is implemented in a deterministic way, and the reservoir-induced noise is suppressed. Numerical simulations indicate that the energy spectrum of the non-Hermitian dynamical matrix obtained via the measurement of the resonators is in accordance with the theoretical prediction. Moreover, we demonstrate the parity discrimination for the state of two four-level qudits as an application, exhibiting the potential of the non-Hermitian dynamics in the field of quantum measurement. This work opens a new avenue for the realization of non-Hermitian dynamics and may have a significant implication in exploring the non-Hermitian phenomena.

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