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Highly-sensitive NO,NO2,and NH3 measurements with an open-multipass cell based on mid-infrared wavelength modulation spectroscopy

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Chinese Physics B 2018年第4期27卷 250-257页

作者： Xiang Chen Chen-Guang Yang Mai Hu Jian-kang Shen Er-Chao Niu Zhen-Yu Xu Xue-Li Fan Min Wei Lu Yao Ya-Bai He Jian-Guo Liu rui-feng kan Key Laboratory of Environmental Optics and Technology Anhui Institute of Optics and Fine Mechanics Chinese Academy of Sciences Hefei 2300314 China University of Science and Technology of China Hefei 230022 China Jiangsu Environmental Monitoring Center Nanjing 210036 China

A compact prototype based on mid-infrared wavelength modulation spectroscopy（WMS）is developed for the simul-taneous monitoring of NO,NO2,and NH3 in the urban *** quantum cascade lasers（QCLs）with central frequencies around 1900.0 cm^-1,1600.0 cm^-1,and 1103.4 cm^-1are used for NO,NO2,and NH3detections,respectively,by timedivision *** open-path multi-pass cell of 60-m optical path length is applied to the instrument for high sensitivity and reducing the response time to less than 1 *** prototype achieves a sub-ppb detection limit for all the three target gases with an average time of about 100 *** instrument is installed in the Jiangsu environmental monitoring center to conduct performance tests on ambient *** 24-hour measurements show good agreement with the results of a reference instrument based on the chemiluminescence technique.

关键词： wavelength modulation spectroscopy optical sensing atmospheric monitoring time division multiplexing quantum cascade laser mid-infrared laser spectroscopy

Development of a Broadly Tunable Mid-Infrared Laser Source for Highly Sensitive Multiple Trace Gas Detection

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Journal of Electronic Science and Technology of China 2008年第4期6卷 361-364页

作者： Xiao-Juan Cui feng-Zhong Dong Yu-Jun Zhang rui-feng kan Yi-Ben Cui Min Wang Dong Chen Jian-Guo Liu Wen-Qing Liu Key Laboratory of Environmental Optics and Technology Anhui Institute of Optics and Fine Mechanics ChineseAcademy of Sciences Hefei 230031 China

A room-temperature broadly tunable mid-infrared difference frequency laser source for highly sensitive trace gas detection has been developed recently in our laboratory. The mid-infrared laser system is based on quasi-phase-matched （QPM） difference frequency generation （DFG） in a multigrating, temperature-controlled periodically poled LiNbO3 （PPLN） crystal and employs two near-infrared diode lasers as pump sources. The mid-infrared coherent radiation generated is tunable from 3.2 μm to 3.7μm with an output power of about 100 μW. By changing one of the pump laser head with another wavelength range, we can readily obtain other needed mid-infrared wavelength range cover. The performance of the mid-infrared laser system and its application to highly sensitive spectroscopic detection of CH4, HCl, CH2O, and NO2 has been carried out. A multi-reflection White cell was used in the experiment gaining ppb-level sensitivity. The DFG laser system has the features of compact, room-temperature operation, narrow line-width, and broadly continuous tunable range for potential applications in industry and environmental monitoring.

关键词： DFG mid-infrared laser source,multi-gases detection.

Practical approach for detecting k-nonseparability of multipartite quantum states

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 32-48页

作者： Jie Guo Jinchuan Hou Xiaofei Qi kan He College of Mathematics Taiyuan University of Technology School of Mathematics and Statistics Shanxi University Key Laboratory of Complex Systems and Data Science of Ministry of Education Shanxi University

The instantaneous detection of entanglement in quantum states poses a significant challenge in the fields of quantum computation and quantum information, and there are no practical methods or tools to complete this task satisfactorily so far. We propose a sufficient and necessary criterion of k-nonseparability for any n-partite finite or infinite dimensional systems, 2 ≤ k ≤ n. This criterion serves as the foundation for a practical scheme designed to detect entanglement and k-nonseparability across multipartite finite-dimensional systems. To exemplify the application of our scheme, we have developed a software tool that facilitates swift and precise identification of entanglement, k-nonseparability, and genuine entanglement within n-qubit systems, specifically tailored for systems with 2 ≤ n ≤ 4.

关键词： multipartite systems entanglement states entanglement witnesses ${\bm~k}$-nonseparability

Effects of the extrusion parameters on microstructure,texture and room temperature mechanical properties of extruded Mg-2.49Nd-1.82Gd-0.2Zn-0.2Zr alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 136-146页

作者： Chenjin Zhang Guangyu Yang Lei Xiao Zhiyong kan Jing Guo Qiang Li Wanqi Jie State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China College of Materials Science and Engineering Fuzhou UniversityFuzhou 350108China College of Chemistry and Environmental Science Qujing Normal UniversityQujing 655011China

Microstructure,texture,and mechanical properties of the extruded Mg-2.49Nd-1.82Gd-0.2Zn-0.2Zr alloy were investigated at different extrusion temperatures(260 and 320℃),extrusion ratios(10:1,15:1,and 30:1),and extrusion speeds(3 and 6 mm/s).The experimental results exhibited that the grain sizes after extrusion were much finer than that of the homogenized alloy,and the second phase showed streamline distribution along the extrusion direction(ED).With extrusion temperature increased from 260 to 320℃,the microstructure,texture,and mechanical properties of alloys changed *** dynamic recrystallization(DRX)degree and grain sizes enhanced as the extrusion ratio increased from 10:1 to 30:1,and the strength gradually decreased but elongation(EL)*** the extrusion speed increased from 3 to 6 mm/s,the grain sizes and DRX degree increased significantly,and the samples presented the typical-rare-earth(RE)*** alloy extruded at 260℃ with extrusion ratio of 10:1 and extrusion speed of 3 mm/s showed the tensile yield strength(TYS)of 213 MPa and EL of 30.6%.After quantitatively analyzing the contribution of strengthening mechanisms,it was found that the grain boundary strengthening and dislocation strengthening played major roles among strengthening *** results provide some guidelines for enlarging the industrial application of extruded Mg-RE alloy.

关键词： Mg-rare earth alloys extrusion temperature extrusion ratio extrusion speed strengthening mechanisms

Morphology-controlled growth of large-area PtSe_(2) films for enhanced hydrogen evolution reaction

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Rare Metals 2022年第4期41卷 1314-1322页

作者： rui Hao Qing-Liang feng Xiao-Jian Wang Yi-Chen Zhang kan-She Li College of Chemistry and Chemical Engineering Polymer Research InstituteXi’an University of Science and TechnologyXi’an 710054China Key Laboratory of Special Functional and Smart Polymer Materials of MIIT School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China

Transition metal dichalcogenides(TMDs)have emerged as a promising electrocatalyst for hydrogen evo-lution reaction(HER)due to its excellent conductivity and abundant electrocatalytic active sites of its *** nanowall can expose abundant of edges so that they tend to show better catalytic performance for hydrogen evolution ***,PtSe_(2) nanowall films with morphology controlled at centimeters level are synthesized by selenizing Pt *** dynamic and thermodynamics of selenation reaction are *** nanowall structure can be obtained by controlling the growth temperature,and the thickness of nanowall can be tuned by the original thickness of Pt *** Pt atoms can be rearranged into ordered distribution at 550℃ and can be induced to well-ordered PtSe_(2) nanowalls *** well-ordered PtSe_(2) nanowall films show excellent HER performance,with an overpotential of 0.3 V at-10 mA·cm^(-2) and a Tafel slope of~52 mV·dec^(-1).This work demonstrates the great potential of activated 2D PtSe_(2) as an ultrathin film catalyst for the HER,which is valuable to provide instruction and afford experience for further application at industrial level.

关键词： Large area PtSe2 Nanowall Morphology controlled HER

Si掺杂对Ga_(2)O_(3)/BP异质结光电性能调控的第一性原理研究

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原子与分子物理学报 2025年第4期42卷 131-137页

作者：李佳宏郝增瑞薛瑞鑫阚红梅关玉琴内蒙古工业大学理学院呼和浩特010010

近年来,氧化镓(Ga_(2)O_(3))是新一代超宽禁带(4.9 eV)半导体,基于优越的热稳定和化学稳定性、高击穿场强和可见光透过率等优点,在日盲紫外探测器和透明光电器件领域中引起了广泛的关注.但是,Ga_(2)O_(3)基光电器件存在迁移率较低而限... 详细信息

近年来,氧化镓(Ga_(2)O_(3))是新一代超宽禁带(4.9 eV)半导体,基于优越的热稳定和化学稳定性、高击穿场强和可见光透过率等优点,在日盲紫外探测器和透明光电器件领域中引起了广泛的关注.但是,Ga_(2)O_(3)基光电器件存在迁移率较低而限制其应用的现象,而构建合适的Ga_(2)O_(3)异质结是改善光电探测器的光电性能的有效手段之一.基于第一性原理构建β-Ga_(2)O_(3)/BP异质结模型,研究了氧空位(Vo)和Si掺杂对β-Ga_(2)O_(3)/BP异质结光电性质的调控以及相关机理.结果显示:β-Ga_(2)O_(3)/BP异质结结构有效降低β-Ga_(2)O_(3)功函数,提高灵敏度,Si掺杂降低结合能,增强稳定性;β-Ga_(2)O_(3)/BP异质结有效减小带隙,Si掺杂以及氧空位的存在,进一步减小带隙,增强光导电性,并且Si掺杂引起了光电导各向异性.此结果对改善Ga_(2)O_(3)基异质结光电性能提供理论参考.

关键词： β-Ga_(2)O_(3)/BP异质结缺陷光电性质第一性原理

Damage Imaging in Mesoscale Concrete Modeling Based on the Ultrasonic Time-Reversal Technique

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Acta Mechanica Solida Sinica 2020年第1期33卷 61-70页

作者： kan feng Qian Zhao Yaping Qiu Faculty of Civil Engineering and Mechanics Jiangsu UniversityZhenjiang 212013China Hengshen Co. Ltd.Zhenjiang 212314China

A novel method combining the time-reversal method(TRM)with wavelet analysis was proposed for damage imaging in mesoscale concrete *** damage was imaged by the convergence of time-reversed wave signals after wavelet *** numerical study,three concrete models of different damage sizes were built with randomly distributed aggregate *** time-reversal process was simulated using the reverse damage-scattered ultrasonic wave signals as excitations recorded by the ***,the wavelet analysis was employed to extract certain frequency component,which can enhance detection precision and the signalto-noise *** damage imaging showed clearly the location of the *** results from experimental testing also demonstrated that this detection technique is an efficient and effective method for damage imaging in mesoscale concrete.

关键词： Damage imaging Mesoscale concrete Time-reversal method Wavelet analysis

A Flexible Smart Healthcare Platform Conjugated with Artificial Epidermis Assembled by Three‑Dimensionally Conductive MOF Network for Gas and Pressure Sensing

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Nano-Micro Letters 2025年第2期17卷 601-620页

作者： Qingqing Zhou Qihang Ding Zixun Geng Chencheng Hu Long Yang Zitong kan Biao Dong Miae Won Hongwei Song Lin Xu Jong Seung Kim State Key Laboratory of Integrated Optoelectronics College of Electronic Science and EngineeringJilin UniversityChangchun 130012People’s Republic of China Department of Chemistry Korea UniversitySeoul 02841Republic of Korea TheranoChem Incorporation Seoul 02856Republic of Korea

The rising flexible and intelligent electronics greatly facilitate the noninvasive and timely tracking of physiological information in telemedicine *** building bionic-sensitive moieties is vital for designing efficient electronic skin with advanced cognitive functionalities to pluralistically capture external ***,realistic mimesis,both in the skin’s three-dimensional interlocked hierarchical structures and synchronous encoding multistimuli information capacities,remains a challenging yet vital need for simplifying the design of flexible logic ***,we construct an artificial epidermal device by in situ growing Cu_(3)(HHTP)_(2) particles onto the hollow spherical Ti_(3)C_(2)T_(x) surface,aiming to concurrently emulate the spinous and granular layers of the skin’s *** bionic Ti_(3)C_(2)T_(x)@Cu_(3)(HHTP)_(2) exhibits independent NO_(2) and pressure response,as well as novel functionalities such as acoustic signature perception and Morse code-encrypted message ***,a wearable alarming system with a mobile application terminal is self-developed by integrating the bimodular senor into flexible printed *** system can assess risk factors related with asthmatic,such as stimulation of external NO_(2) gas,abnormal expiratory behavior and exertion degrees of fingers,achieving a recognition accuracy of 97.6%as assisted by a machine learning *** work provides a feasible routine to develop intelligent multifunctional healthcare equipment for burgeoning transformative telemedicine diagnosis.

关键词： Ti_(3)C_(2)T_(x)@Cu_(3)(HHTP)_(2)composites NO_(2)/pressure flexible sensors Health-monitoring Machine learning

Application of homogenization techniques for inflow transport approximation on light water reactor analysis

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Nuclear Science and Techniques 2022年第1期33卷 67-80页

作者： Xiang Xiao kan Wang Tong-rui Yang Yi-Xue Chen Department of Engineering Physics Tsinghua UniversityBeijing 100084China State Power Investment Corporation Research Institute Co.LtdBeijing 100029China

The transport cross-section based on inflow transport approximation can significantly improve the accuracy of light water reactor(LWR)analysis,especially for the treatment of the anisotropic scattering *** previous inflow transport approximation is based on the moderator cross-section and normalized fission source,which is approximated using transport *** the accuracy of reactivity is increased,the P0 flux moment has a large error in the Monte Carlo *** this study,an improved inflow transport approximation was introduced with homogenization techniques,applying the homogenized cross-section and accurate fission *** numerical results indicated that the improved inflow transport approximation can increase the P0 flux moment accuracy and maintain the reactivity calculation precision with the previous inflow transport approximation in typical LWR *** addition to this investigation,the improved inflow transport approximation is related to the temperature *** improved inflow transport approximation is flexible and accurate in the treatment of the anisotropic scattering effect,which can be directly used in the temperature-dependent nuclear data library.

关键词： Inflow transport approximation Anisotropic scattering effect Homogenization techniques Light water reactor