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2021年老挝M_(S)6.0地震序列研究

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地震研究 2025年第1期48卷 1-9页

作者：孙楠贺素歌刘自凤李利波云南省地震局云南昆明650224

云南地震活动与周边强震存在“构造相连,动力同源”的特征,研究周边强震的序列演化特征及发震构造,对云南地区地震研究具有重要意义。2021年12月24日老挝M_(S)6.0地震发生在滇西南地区的NW向整董断裂附近,震源机制解显示,此次地震是一... 详细信息

云南地震活动与周边强震存在“构造相连,动力同源”的特征,研究周边强震的序列演化特征及发震构造,对云南地区地震研究具有重要意义。2021年12月24日老挝M_(S)6.0地震发生在滇西南地区的NW向整董断裂附近,震源机制解显示,此次地震是一次走滑型破裂事件,破裂方向与区域构造特征一致。老挝M_(S)6.0地震序列属于前震-主震-余震型序列,主震前震中附近出现3~4级地震非常活跃的现象,前震序列参数计算显示b值波动相对幅度较大,h值出现“上翘”形态,而余震序列b值和h值变化均相对平稳,主震的同震库伦应力结果表明老挝地震可能对云南地区有应力加载作用。

关键词：老挝M_(S)6.0地震前震序列余震序列序列参数

掺杂对TiC_(2)纳米片析氢反应的第一性原理研究

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原子与分子物理学报 2025年第3期42卷 29-34页

作者：孙楠楠赵翠莲潘美玲赵志超张宇河北水利电力学院基础部沧州061000 河北省数据中心相变热管理技术创新中心沧州061000

过渡金属二碳族化物单层作为一种廉价而丰富的材料,在制氢催化剂方面的应用越来越受到人们的关注.在这项工作中,基于第一性原理计算研究了掺杂二碳化钛单层的析氢还原.我们发现掺杂元素和浓度对单分子膜的催化能力有强烈的影响.结果表明... 详细信息

过渡金属二碳族化物单层作为一种廉价而丰富的材料,在制氢催化剂方面的应用越来越受到人们的关注.在这项工作中,基于第一性原理计算研究了掺杂二碳化钛单层的析氢还原.我们发现掺杂元素和浓度对单分子膜的催化能力有强烈的影响.结果表明,在高氢覆盖率内,O和V掺杂能有效的降低氢吸附的吉布斯自由能.低密度掺杂可以提高催化能力.我们进一步研究表明,由于V原子在二碳化钛(TiC_(2))单层中具有最低的负形成能,因此比其他过渡金属原子更容易取代Ti原子.期望掺钒TiC_(2)单分子膜能以更高的效率应用于水电解.

关键词：密度泛函理论 TiC_(2)单层片覆盖率掺杂

Structural adaptive and optimal speckle filtering in multilook full polarimetric SAR images

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Journal of Systems Engineering and Electronics 2007年第2期18卷 217-222页

作者： sun nan Zhang Bingchen Wang Yanfei Graduate School Chinese Academy of Sciences Beijing 100039 P. R. China Inst. of Electronics Chinese Academy of Sciences Beijing 100080 P. R. China (Received December 2 2005

A novel approach is proposed for speckle reduction in multilook full polarimetric SAR images. In contrast to others, this approach adopts an enhanced structure detection method to estimate the parameters of the polarimetric covariance matrix for the multilook polarimetric whitening filtering （MPWF） algorithm and thus a structural adaptive and optimal speckle filter is developed. To evaluate the present approach, NASA SIR-C/X- SAR, L band, four-look processed polarimetric SAR data of the Tian-Mountain Forest is used for simulation. Experimental results demonstrate the effectiveness of this novel filtering algorithm in case of both speckle reduction and preservation of texture information. Comparisons with other methods are also made.

关键词： MPWF Geometrical-ratio detectors ESDMPWF Speckle Multilook polarimetric SAR.

Synthesis and application of PLGA labeled with ^(125)I

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Nuclear Science and Techniques 2006年第1期17卷 48-52页

作者： HUA nan sun Jiao The Ninth People＇s Hospital Shanghai Jiaotong University~Shanghai Biomaterial Research and Test Center Shanghai 200011 China

The weight loss in vivo degradation of poly (lactide-co-glycolide) (PLGA) radiolabeled with 125I was in-vestigated. PLGA with molecular weight (Mw) of 84000(LA/GA = 85/15) were labeled with 125I in the chloroform media by circularly heating and round films of about 15 mm in diameter were formed. The composition and Mw of the 125I-PLGA were characterized by 1H-NMR and viscosimeter. The weight loss of this copolymer in vitro and in vivo degradation was quantified by determining radioactivity of materials. The results indicated that PLGA exhibited sig-nificantly faster degradation in vivo than that of in vitro conditions.

关键词： ^125I 降解聚乙烯同位素示踪

Performance Analysis of an Integrated Supercritical CO_(2) Recompression/Absorption Refrigeration/Kalina Cycle Driven by Medium-Temperature Waste Heat

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Journal of Thermal Science 2022年第6期31卷 2051-2067页

作者： SU Ruizhi YU Zeting WANG Daohan sun Bo sun Jia’nan School of Energy and Power Engineering Shandong UniversityJi'nan 250061China Shandong Engineering Laboratory for High-Efficiency Energy Conservation and Energy Storage Technology&Equipment Shandong UniversityJi'nan 250061China School of Electrical Engineering Shandong UniversityJi'nan 250061China School of Control Science and Engineering Shandong UniversityJi'nan 250061China

A novel power and cooling cogeneration system which combines a supercritical CO_(2) recompression cycle(SCRC), an ammonia-water absorption refrigeration cycle(AARC) and a Kalina cycle(KC) is proposed and investigated for the recovery of medium-temperature waste heat. The system is based on energy cascade utilization, and the waste heat can be fully converted through the simultaneous operation of the three sub-cycles. A steady-state mathematical model is built for further performance study of the proposed system. When the exhaust temperature is 505℃, it is shown that under designed conditions the thermal efficiency and exergy efficiency reach 30.74% and 61.55%, respectively. The exergy analysis results show that the main exergy destruction is concentrated in the heat recovery vapor generator(HRVG). Parametric study shows that the compressor inlet pressure, the SCRC pressure ratio, the main compressor and the turbine I inlet temperature, and the AARC generator pressure have significant effects on thermodynamic and economic performance of the combined system. The findings in this study could provide guidance for system design to achieve an efficient utilization of medium-temperature waste heat(e.g., exhaust heat from gas turbine, high-temperature fuel cells and internal combustion engine).

关键词： waste heat utilization cogeneration system supercritical CO_(2)recompression cycle absorption refrigeration cycle Kalina cycle

Entropy method for determination of weight of evaluating indicators in fuzzy synthetic evaluation for water quality assessment

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Journal of Environmental Sciences 2006年第5期18卷 1020-1023页

作者： ZOU Zhi-hong YUN Yi sun Jing-nan School of Economics and Management Beihang University Beijing 100083 China

Considering the difficulty of fuzzy synthetic evaluation method in calculation of the multiple factors and ignorance of the relationship among evaluating objects, a new weight evaluation process using entropy method was introduced. This improved method for determination of weight of the evaluating indicators was applied in water quality assessment of the Three Gorges reservoir area. The results showed that this method was favorable for fuzzy synthetic evaluation when there were more than one evaluating objects. One calculation was enough for calculating every monitoring point. Compared with the original evaluation method, the method predigested the fuzzy synthetic evaluation process greatly and the evaluation results are more reasonable.

关键词： water quality evaluation fuzzy weight of evaluating indicator entropy method

Photo-Dimerization Characteristics of Coumarin Pendants within Amphiphilic Random Copolymer Micelles

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Chinese Journal of Polymer Science 2015年第8期33卷 1086-1095页

作者： Huan Chang Mei Shi Ya-nan sun 江金强 Key Laboratory of Applied Surface and Colloid Chemistry Ministry of Education School of Chemistry & Chemical EngineeringShaanxi Normal University Shandong Vocational College of Industry

The photo-dimerization characteristics of coumarin pendants within amphiphilic random copolymer micelles in aqueous solution was comprehensively investigated using various selected wavelength light in the UV-Vis-NIR region. The time-dependent photo-dimerization degree （PD） changes in the photo-dimerization experiments showed saturating behaviors with intensity-independent of PDmax values at 28%, 44%, 92%, 85%, 36%, 35%, 32% and 31% for 254, 288, 320, 360, 400, 500, 650 and 900 nm irradiations, respectively. The irradiation experiments at 254 and 288 nm announced the occurring of an asymmetric equilibrium of photo-dimerization and photo-cleavage at the used conditions. Both the alternative irradiation cycles of 360 and 254 nm, 650 and 254 nm showed a partially, but evidently reversible photo-dimerization tendency.

关键词： Polymer micelles Coumarin UV-Vis-NIR Photo-dimerization Photo-cleavage.

Wind-induced internal pressure response for structure with single windward opening and background leakage

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第3期9卷 313-321页

作者： Shi-ce YU Wen-juan LOU Bing-nan sun College of Civil Engineering and Architecture Zhejiang University Hangzhou 310027 China Department of Architecture Engineering Ningbo College of Technology Zhejiang University Ningbo 315100 China

Theoretical analysis and wind tunnel tests were carried out to study wind-induced intemal pressure response for the structure with single windward opening and background leakage. Its goveming differential equation was derived by the Bemoulli equation in an unsteady-isentropic form. Numerical examples were provided to study the additive damping caused by background leakage in laminar and turbulent flow, and the influence of background leakage on fluctuating internal pressure response was quantized. A series of models for low-rise building with various opening ratios and background leakage were designed and wind tunnel tests were conducted. It is shown that the fluctuating intemal pressure reduces when the background leakage are considered and that the effect of background leakage can be predicted accurately by the governing differential equation deduced in this paper.

关键词： Single windward opening Internal pressure Background leakage Governing equation Time-history analysis

Adjuvant immunotherapy in resected esophageal squamous cell carcinoma:a gospel to the non-pCRs

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Signal Transduction and Targeted Therapy 2021年第9期6卷 2611-2612页

作者： Zhihui Zhang nan sun Jie He Department of Thoracic Surgery National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina State Key Laboratory of Molecular Oncology National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina

A recent study1 published in The New England Journal of Medicine by Kelly RJ presented interim results from a phase 3 clinical trial(CheckMate 577),a global,randomized,double-blind,interventional trial to evaluate a novel approach of adjuvant nivolumab after neoadjuvant chemoradiotherapy(nCRT)and surgery for esophageal or gastroesophageal junction(GEJ)cancer.

关键词： esophageal clinical Kelly