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Nonlinear Absorption and Dispersion Response in Optically Dense Media Driven by a Single-Mode Laser

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Communications in Theoretical Physics 2006年第1X期46卷 130-134页

作者： li Jia-Hua liU Ji-Bing XIE Xiao-Tao LUO Jin-ming Department of Physics Huazhong University of Science and Technology Wuhan 430074 China

Taking the density-dependent near dipole-dipole （NDD） interaction into consideration, we theoretically investigate the response of nonlinear absorption and dispersion in optically dense media of three-level atoms driven by a single-mode probe laser. The influence of the NDD effects on the absorption and dispersion spectra of the probe field is predicted via numerical calculations. It is shown that the NDD effects reduce gradually to transient absorption and amplification with the increase of the strengths of the NDD interaction, but do not change the steady-state behavior. Due to the presence of the NDD effects, steady-state absorption spectra exhibit asymmetric double-peak structure and overall shifts when a continuous-wave （cw） probe field is applied. However, frequency dispersion spectra are insensitive to them near the zero detuning.

关键词： absorption spectra dispersion spectra near dipole-dipole interactions

Statistical performance of IF estimation of LFM signals with timevarying amplitude using the peak of WVD

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Journal of Systems Engineering and Electronics 2005年第4期16卷 787-791页

作者： Chen Guanghua Ma Shiwei Qin Tinghao Wang Jian li ming Cao Jialin Microelectronic Research & Development Center Shanghai Univ. Shanghai 200072 P. R. China

The instantaneous frequency （IF） estimation of the linear frequency modulated （LFM） signals with time-varying amplitude using the peak of the Wigner-Ville distribution （WVD） is studied. Theoretical analysis shows that the estimation on LFM signals with time-varying amplitude is unbiased, only if WVD of time-varying amplitude reaches its maximum at frequency zero no matter in which time. The statistical performance in the case of additive white Guassian noise is evaluated and an analytical expression for the variance is provided. The simulations using LFM signals with Gaussian envelope testify that IF can be estimated accurately using the peak of WVD for four models of amplitude variation. Furthermore the statistical result of estimation on the signals with amplitude descending before rising is better than that of the signals with constant amplitude when the amplitude variation rate is moderate.

关键词： instantaneous frequency linear frequency modulated signals Wigner-Ville distribution statistical performance variance.

Synthesis and bioactivity of novel coumarin derivatives containing(E)-methyl 2-(methoxyimino)-2-phenylacetates

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Chinese Chemical Letters 2011年第6期22卷 663-666页

作者： Ai Ying Guan Chang ling liu Zhi Nian li ming Xing Zhang State Key Laboratory of the Discovery and Development of Novel Pesticide Shenyang Research Institute of Chemical Industry Co.Ltd. Shenyang 110021China

Ten coumarin derivatives containing（E）-methyl 2-（methoxyimino）-2-phenylacetate were synthesized and *** compounds were identified by IR,~1H NMR and elemental *** test results indicated that compound 5j（R^1 is methyl and R^2 is n-C_6H_（13）） was the optimal structure in this paper with good fungicidal activity against CDM（85%） at 6.25 mg/L concentration.

关键词： Coumarins Methoxyacrylates Intermediate derivatization method Fungicides

Effects of mechanical vibration on filling and solidification behavior, microstructure and performance of Al/Mg bimetal by lost foam compound casting

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China Foundry 2023年第6期20卷 469-479页

作者： Guang-yu li Feng Guan Wen-ming Jiang Yuan-cai Xu Zheng Zhang Zi-tian Fan State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

Al/Mg bimetal was prepared by lost foam solid-liquid compound casting,and the effects of mechanical vibration on the filling and solidification behavior,microstructure and performance of the bimetal were *** show that the mechanical vibration has a remarkable influence on the filling and solidification *** is found that after mechanical vibration,the filling rate increases and the filling rate at different times is more uniform than that without *** addition,the mechanical vibration also increases the wettability between liquid AZ91D and A356 *** mechanical vibration reduces the horizontal and vertical temperature gradient of the casting and makes the temperature distribution of the whole casting more *** to the Al/Mg bimetal without vibration,the shear strength is improved by 39.76%after the mechanical vibration is applied,due to the decrease of the inclusions and Al_(12)Mg_(17) dendrites,and the refinement and uniform distribution of the Mg_(2)Si particles in the interface of the Al/Mg bimetal.

关键词： lost foam casting filling and solidification processes Al/Mg bimetal mechanical vibration microstructure mechanical properties

Elimination of HBr from CH_3Br by Cu^+ and Au^+:A DFT study

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Chinese Chemical Letters 2008年第7期19卷 881-884页

作者： Tao Hong li Chuan ming Wang Xiang Yi liu Xiao Guang Xie Faculty of Chemistry Southwest Forestry University Kunming 650224 China Department of Biology Honghe University Menzi 661100 China Department of Chemistry Yunnan University Kunming 650091 China

The elimination of HBr from CH3Br by ground state of Cu＋ and Au＋ has been investigated by using DFT methods. A mechanism of one-step HBr elimination leading to CuCH2＋ was identified. For the formation of AuCH2＋, besides the one-step mechanism, another two-step HBr elimination pathway through a C-Br bond insertion intermediate was also found, and this pathway is energetically more favorable than the one-step mechanism. The calculated reaction energy barriers show that the formation of AuCH2＋ is energetically much more favorable than the formation of CuCH2＋. The experimental observations are well explained.

关键词： Copper and gold Alkyl halide HBr elimination

Fast Screening of Chicken Egg Lysozyme in White Wine Products by Extractive Electrospray Ionization Mass Spectrometry

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Chemical Research in Chinese Universities 2012年第2期28卷 200-203页

作者： ZHOU Zhi-quan JIANG Jie li ming ZHAO Zhan-feng FU Jun College of Information Science and Engineering Harbin Institute of Technology at WeihaiWeihai 264209P.R.China Department of Cadre Ward the First Hospital of Jilin UniversityChangehun 130021P.R.China National Institute of Metrology Beijing 100013P.R.China

Fast detection of trace lysozyme,one of the most important food allergens in white wine samples,was achieved by extractive electrospray ionization mass spectrometry without sample pretreatment in this *** multiply-charged ions of m/z1587 were chosen for the quantitative detection of lysozyme in white wine,showing linear dynamic signal responses in a range of 5―75μg/mL with a linearity coefficient of 0.999 and an acceptable relative standard deviation（RSD） of 8.0%―15.0% for directly measuring lysozyme in the complex food *** limit of detection for lysozyme in white wine sample was calculated to be 5 μg/mL,which was lower than the amounts that can provoke allergic reactions（oral test with 3 mg or labial test with 1 mg/mL）.A single sample analysis was completed within 1 *** data demonstrate that extractive electrospray ionization mass spectrometry is a useful tool for fast screening lysozyme in the complex matrix,showing promising application in the rapid detection of food allergen.

关键词： Allergen Lysozyme Extractive electrospray ionization Mass spectrometry Ambient ionization

Solidification in a shell-and-tube thermal energy storage unit filled with longitude fins and metal foam:A numerical study

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Energy and Built Environment 2023年第1期4卷 64-73页

作者： Xiaohu Yang Fengfei Xu Xinyi Wang Junfei Guo ming-Jia li Institute of the Building Environment&Sustainability Technology School of Human Settlements and Civil EngineeringXi’an Jiaotong UniversityXi’an 710049China Key Laboratory of Thermo-Fluid Science and Engineering of Ministry of Education School of Energy and Power EngineeringXi’an Jiaotong UniversityXi’an 710049China Shanghai Industrial Boiler(Wuxi)CO. LTD.Wuxi 214000China

In this study,an innovative thermal energy storage design method was developed by adding the combination of metal foam and fin to phase change materials(PCMs).A numerical model was built and verified based on the comparison among the present model prediction,experimental measurements,and numerical results in open *** highlight the novel design method,four cases including fin-PCM,foam-PCM,fin-foam-PCM,and PCM unit were compared by means of solidification *** temperature distribution,solidification front propa-gation,and buoyancy-induced convection in the liquid PCM were accounted *** results demonstrated that metal foam outperformed fin regarding the improvement on solidification phase *** combination of foam and fin achieved the best performance,leading to a 90.5%reduction in complete energy release time in comparison with the PCM *** proposed design method provided reference potentials for advancing energy storage ***,buoyancy-induced convection in the liquid PCM before solidification was harmful to the formation of solidification front and its movement.A maximal 11.5%prolonging time for the complete solidification was found.

关键词： Thermal energy storage Phase change materials Metal foam Shell and tube heat exchanger Solidification

Dinosaur-bearing strata and K/T boundary in the Luanchuan-Tantou Basin of western Henan Province,China

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Science China Earth Sciences 2011年第8期54卷 1149-1155页

作者： JIANG XiaoJun liU YongQing JI ShuAn ZHANG Xingliao XU li JIA SongHai LO JunChang YUAN ChongXi li ming Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China Henan Geological Museum Zhengzhou 450000 China

The sequence stratigraphy and geochronology of the terrestrial dinosaur-bearing strata,i.e.,the Qiupa Formation,were poorly studied in the Luanchuan-Tantou Basin in western Henan,*** study shows that these strata represent a complete succession from the Late Cretaceous to the early Paleogene,including the K/T boundary,in this *** we report a detailed study of the K/T boundary,especially its stratigraphic sequence,sedimentary characteristics,integrity,continuity,and geological implications.

关键词： western Henan Luanchuan-Tantou Basin dinosaurs stratigraphy K/T boundary

Gastrointestinal symptoms as the first sign of chronic granulomatous disease in a neonate: A case report

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World Journal of Clinical Cases 2021年第32期9卷 9997-10005页

作者： Er-Yan Meng Zi-ming Wang Bing Lei li-Hong Shang Division of Neonatology The Third Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052Henan ProvinceChina Chongqing Medical College Chongqing 400016China

BACKGROUND Chronic granulomatous disease(CGD)characterized by recurrent and severe bacterial and fungal infections is most common in *** SUMMARY We reported a 24-d-old male infant who developed gastrointestinal symptoms as the first sign of *** Gastrointestinal symptoms representing the first sign of CGD are very rare,and prompt diagnosis and treatment with broad-spectrum antibiotics were of crucial importance.

关键词： Chronic granulomatous disease Gastrointestinal symptoms Infant Neonate Fever Diarrhea