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Synthesis and Analysis of Tm^(3+) Doped YF_3 Upconversion Luminescent Nano-materials

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Chinese Journal of Structural Chemistry 2010年第7期29卷 993-1000页

作者： huang Qing-ming Instrumentation Analysis and Research Center College of MaterialsScience and Engineering Fuzhou University Fuzhou Fujian 350002 China

Upconversion （UC） phosphor Tm3＋ doped YF3 nano-erystals were prepared by hydrothermal method under different conditions and characterized by Field Transmission electron microscopy （TEM）, Scanning electron microscopy （SEM） and X-ray diffraction （XRD）. Their UC luminescence properties were studied by fluorescence spectrophotometer with 980 nm diode laser excitation, and impact of different grain sizes and morphology on the UC luminescence intensity was discussed. The fluorescence decay lifetime was calculated by Multi-exponential function fitting method. Results show that UC emission intensity was enhanced with the reduction of grain size, and the decay lifetime is 0.60 us.

关键词： upconversion crystal morphology decay time Rietveld refinement

Crystal Structure of Sar1[H79G]-GDP Which Provides Insight into the Coat-controlled GTP Hydrolysis in the Disassembly of COP Ⅱ

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Chinese Journal of Structural Chemistry 2006年第7期25卷 854-860页

作者： RAO yi-Jian YUAN Cai BIAN Chuan-Bing HOU Xiao-Min LI Yong-Dong ZHAO Geng-Xiang YE Xiao-ming huang Zi-Xiang huang ming-Dong State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter The Chinese Academy of Sciences Fuzhou Fujian 350002 China

Sarl is a small GTPase involved in COPⅡ vesicle transport. Previous studies showed that H79G mutation of Sarl can lock Sarl in its GTP-bound active conformation, stabilize coat assembly, and prevent the disassembly of COP Ⅱ vesicle coats by reducing Sec23/24 GAP- stimulated hydrolysis. We show here that the replacement of His79 by glycine induces a large conformation change in switch Ⅱ and results in the lost of hydrogen bond between His79 and its associated nucleophilic water molecule that was hypothesized to reduce the GAP-stimulated hydrolysis during the COP Ⅱ assembly and disassembly. These results confirm that the switch Ⅱ conformation is important for COP Ⅱ disassembly through coat-controlled GTP hydrolysis.

关键词： Sarl switch Ⅱ COP Ⅱ disassembly crystal structure

药用爬山虎对CIA大鼠血清IL-17和关节滑膜细胞NF-κB表达的影响

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贵阳中医学院学报 2017年第2期39卷 11-15页

作者：徐晖马武开唐芳宁乔怡姚血明黄颖龙小琴贵阳中医学院第二附属医院风湿免疫科贵州贵阳550001

目的:探讨药用爬山虎对牛II型胶原诱导性关节炎大鼠(CIA)关节滑膜细胞核周因子-κB(NF-κB)表达及血清IL-17水平的影响。方法:将40只6周龄雌性wistar大鼠随机分为空白对照组、模型对照组、雷公藤多苷对照组和爬山虎治疗组各10只。除空... 详细信息

目的:探讨药用爬山虎对牛II型胶原诱导性关节炎大鼠(CIA)关节滑膜细胞核周因子-κB(NF-κB)表达及血清IL-17水平的影响。方法:将40只6周龄雌性wistar大鼠随机分为空白对照组、模型对照组、雷公藤多苷对照组和爬山虎治疗组各10只。除空白对照组外,其余各组建立CIA模型,造模第7天开始予爬山虎汤剂和雷公藤水溶液灌胃治疗,连续用药4周,空白对照组和模型对照组灌服等量生理盐水,于末次给药2h后采集血清,处死大鼠,摘取双后肢膝关节分离滑膜,采用ELISA检测血清IL-17的表达,Western-blot检测关节滑膜NF-κB/P65的蛋白表达。结果:与空白对照组比较,模型组大鼠血清IL-17表达增加,爬山虎和雷公藤能够明显降低IL-17的表达(P0.05)。结论:药用爬山虎能够降低CIA模型大鼠血清IL-17的表达,下调关节滑膜细胞NF-κB的蛋白水平。

关键词：类风湿关节炎胶原诱导性关节炎动物模型 NF-κB IL-17 爬山虎

Photoproduction reactionγn→K^(*0)∧in an effective Lagrangian approach

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Chinese Physics C 2022年第2期46卷 57-61页

作者： Neng-Chang Wei yi-ming Zhu Fei huang School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 101408China School of Physical Sciences University of Chinese Academy of SciencesBeijing 101408China

In our previous work[***.C 101,014003(2020)],the photoproduction reactionγp→K^(*+)Λwas investigated within an effective Lagrangian *** reaction amplitudes were constructed by including the t-channel K,K^(*),and k exchanges,u-channelΛ,∑,and∑^(*)exchanges,s-channel N,N(2000)5/2^(+),and N(2060)5/2^(-)exchanges,and interaction *** data on the differential cross sections and spin density matrix elements were described *** this study,we investigate the photoproduction reactionγn→K^(*0)Λbased on the same reaction mechanism as that ofγp→K^(*+)Λto obtain a unified description of the data forγp→K^(*+)Λandγn→K^(*0)Λwithin the same *** hadronic coupling constants,form factor cutoffs,and the resonance masses and widths in the present calculations remain the same as in our previous work forγp→K^(*+)Λ.The available differential cross-section data forγn→K^(*0)Λare well *** analysis shows that the cross sections ofγn→K^(*0)Λare dominated by the contributions of the t-channel K exchange,while the s-channel N(2000)5/2+and N(2060)5/2-exchanges also provide considerable contributions.

关键词： photoproduction effective Lagrangian approach gauge invariance

Phase-Field Simulation of Sintering Process:A Review

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Computer Modeling in Engineering & Sciences 2024年第8期140卷 1165-1204页

作者： ming Xue Min yi State Key Laboratory ofMechanics and Control forAerospace Structures&Institute for Frontier Science&Key Laboratory for Intelligent Nano Materials and Devices of Ministry of Education&College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics(NUAA)Nanjing210016China

Sintering,a well-established technique in powder metallurgy,plays a critical role in the processing of high melting point materials.A comprehensive understanding of structural changes during the sintering process is essential for effective product *** phase-field method stands out for its unique ability to simulate these structural *** its widespread application,there is a notable absence of literature reviews focused on its usage in sintering ***,this paper addresses this gap by reviewing the latest advancements in phase-field sintering models,covering approaches based on energy,grand potential,and entropy *** characteristics of various models are extensively discussed,with a specific emphasis on energy-based models incorporating considerations such as interface energy anisotropy,tensor-form diffusion mechanisms,and various forms of rigid particle motion during ***,the paper offers a concise summary of phase-field sintering models that integrate with other physical fields,including stress/strain fields,viscous flow,temperature field,and external electric *** conclusion,the paper provides a succinct overview of the entire content and delineates potential avenues for future research.

关键词： Phase-field model review sintering additive manufacturing

Clinical findings and imaging features of 67 nasopharyngeal carcinoma patients with postradiation nasopharyngeal necrosis

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Chinese Journal of Cancer 2013年第10期32卷 533-538页

作者： ming-Yuan Chen Hai-Qiang Mai Rui Sun Xiang Guo Chong Zhao ming-huang Hong yi-Jun Hua State Key Laboratory of Oncology in South China Department of Nasopharyngeal Carcinoma Department of Radiotherapy Sun Yat-sen University Cancer Center

Postradiation nasopharyngeal necrosis is an important late effect of radiotherapy that affects prognosis in patients with nasopharyngeal *** the present study,we reviewed the clinical and imaging features of 67 patients with pathologically diagnosed postradiation nasopharyngeal necrosis who were treated at Sun Yat-sen University Cancer Center between June 2006 and January *** clinical manifestations,endoscopic findings,and imaging features were *** nasopharyngeal necrosis was limited to a local site in the nasopharyngeal region,and the tissue defect was not obvious,whereas deep parapharyngeal ulcer or signs of osteoradionecrosis in the basilar region was observed in serious *** with osteoradionecrosis and/or exposed carotid artery had a high *** conclusion,Postradiation nasopharyngeal necrosis has characteristic magnetic resonance imaging appearances,which associate well with clinical findings,but pathologic examination is essential to make the diagnosis.

关键词：临床表现鼻咽癌影像学特征性坏死放疗患者放射治疗

Signal modeling and impulse response shaping for semiconductor detectors

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Nuclear Science and Techniques 2022年第4期33卷 72-82页

作者： Xue-Yuan Wang Jian-Bin Zhou ming Wang Huai-Ping Wang Xu Hong yi Liu Ping huang College of Nuclear Technology and Automation Engineering Chengdu University of TechnologyErxian BridgeNo.1 East 3 RoadChenghua DistrictChengdu 610059China Jiangxi Engineering Technology Research Center of Nuclear Geoscience Data Science and System East China University of TechnologyNanchang 330013China China Testing Technology Co. LtdChengdu 610021China

The output-signal models and impulse response shaping(IRS)functions of semiconductor detectors are important for establishing high-precision measurement *** this paper,an output-signal model for semiconductor detector systems is *** to the proposed model,a multistage cascade deconvolution IRS algorithm was developed using the C-R inverse system,R-C inverse system,and differentiator *** silicon drift detector signals acquired from the analog-to-digital converter were *** experimental results indicated that the shaped pulses obtained using the proposed model had no undershoot,and the average peak base width of the output shaped pulses was reduced by 36%compared with that for a simple model proposed in a previous work[1].Offline processing results indicated that compared with the traditional IRS algorithm,the average peak base width of the output shaped pulses obtained using the proposed algorithm was reduced by 11%,and the total elapsed time required for pulse shaping was reduced by 26%.The proposed algorithm avoids recursive *** the sampling frequency of the digital system reaches 100 MHz,the proposed algorithm can be simplified to integer *** proposed IRS algorithm can be applied to high-resolution energy spectrum analysis,highcounting rate energy spectrum correction,and coincidence and anti-coincidence measurements.

关键词： Output-signal model Impulse response shaping C-R inverse system R-C inverse system Integer arithmetic

Application of Bayesian regularized BP neural network model for analysis of aquatic ecological data—A case study of chlorophyll-a prediction in Nanzui water area of Dongting Lake

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Journal of Environmental Sciences 2005年第6期17卷 946-952页

作者： XU Min ZENG Guang-ming XU Xin-yi huang Guo-he SUN Wei JIANG Xiao-yun College of Environmental Science and Engineering Hunan University Changsha 410082 China Sino-Canadian Center of Energy and Environment Research University of Regina Regina SK S4S 0A2 Canada

Bayesian regularized BP neural network（BRBPNN） technique was applied in the chlorophyll-α prediction of Nanzui water area in Dongting Lake. Through BP network interpolation method, the input and output samples of the network were obtained. After the selection of input variables using stepwise/multiple linear regression method in SPSS i1.0 software, the BRBPNN model was established between chlorophyll-α and environmental parameters, biological parameters. The achieved optimal network structure was 3-11-1 with the correlation coefficients and the mean square errors for the training set and the test set as 0.999 and 0.000？8426, 0.981 and 0.0216 respectively. The sum of square weights between each input neuron and the hidden layer of optimal BRBPNN models of different structures indicated that the effect of individual input parameter on chlorophyll- α declined in the order of alga amount 〉 secchi disc depth（SD）〉 electrical conductivity （EC）. Additionally, it also demonstrated that the contributions of these three factors were the maximal for the change of chlorophyll-α concentration, total phosphorus（TP） and total nitrogen（TN） were the minimal. All the results showed that BRBPNN model was capable of automated regularization parameter selection and thus it may ensure the excellent generation ability and robustness. Thus, this study laid the foundation for the application of BRBPNN model in the analysis of aquatic ecological data（chlorophyll-α prediction） and the explanation about the effective eutrophication treatment measures for Nanzui water area in Dongting Lake.

关键词： Dongting Lake chlorophyll-a Bayesian regularized BP neural network model sum of square weights

Spectrometer of hard X-ray imager payload onboard the ASO-S mission

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Nuclear Science and Techniques 2019年第8期30卷 92-99页

作者： Yan Zhang Jian-Hua Guo Zhe Zhang Deng-yi Chen yi-ming Hu Yong-Qiang Zhang Tao Ma Yong-yi huang Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210034China University of Chinese Academy of Sciences Beijing 100049China

A spaceborne hard X-ray spectrometer, composed of an array of 99 scintillation detectors and associated readout electronics, has been developed for the hard X-ray imager(HXI). The HXI is one of the three payloads onboard the advanced space-based solar observatory(ASO-S), which is scheduled to be launched in early 2022 as the first Chinese solar satellite. LaBr3 scintillators and photomultiplier tubes with a super bialkali cathode are used to achieve an energy resolution better than 20% at 30 ***, a new multi-channel charge-sensitive readout application-specific integrated circuit guarantees high-frequency data acquisition with low power consumption. This paper presents a detailed design of the spectrometer for the engineering model of the HXI and discusses its noise and linearity performance.

关键词： Solar radiation detection X-ray spectrometer Hard X-ray imager ASO-S