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Modified sepiolite stabilized stearic acid as a form-stable phase change material for thermal energy storage
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作者 Chuanchang Li Xinke Peng +1 位作者 jianjun he Jian Chen 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第9期1835-1845,共11页
Sepiolite(ST) was used as a supporting matrix in compiste phase change materials(PCMs) due to its unique microstructure, good thermal stability, and other raw material advantages. In this paper, microwave acid treatme... Sepiolite(ST) was used as a supporting matrix in compiste phase change materials(PCMs) due to its unique microstructure, good thermal stability, and other raw material advantages. In this paper, microwave acid treatment were innovatively used for the modification of sepiolite. The modified sepiolite(ST_(m)) obtained in different hydrochloric acid concentrations(0.25, 0.5, 0.75, and 1.0 mol·L^(-1)) was added to stearic acid(SA) via vacuum impregnation method. The thermophysical properties of the composites were changed by varying the hydrochloric acid concentration. The SA-ST_(m0.5)obtained by microwave acid treatment at 0.5 mol·L^(-1)hydrochloric acid concentration showed a higher loading capacity(82.63%) than other composites according to the differential scanning calorimeter(DSC) analysis. The melting and freezing enthalpies of SA-ST_(m0.5)were of 152.30 and 148.90 J·g^(-1), respectively. The thermal conductivity of SA-ST_(m0.5)was as high as 1.52 times that of pure SA. In addition, the crystal structure, surface morphology, and microporous structure of ST_(m)were studied, and the mechanism of SAST_(m0.5)performance enhancement was further revealed by Brunauere Emmett Teller(BET) analysis. Leakage experiment showed that SAST_(m0.5)had a good morphological stability. These results demostrate that SA-ST_(m0.5)has a potential application in thermal energy storage. 展开更多
关键词 SEPIOLITE stearic acid phase change materials thermal energy storage
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2022年度气象联合基金项目评审简析
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作者 何建军 张宇 +5 位作者 刘哲 杨蕾 任颖 葛非 郭郁葱 李婧 《大气科学》 CSCD 北大核心 2023年第3期920-924,共5页
2022年气象联合基金资助数值预报模式关键技术、灾害天气监测预报理论与方法和人工智能气象应用技术三个核心领域,共接收申请64项,其中不同单位属性的合作申请占87.5%。申请书关键词分析发现,气象联合基金与地球科学部“天气及气候系统... 2022年气象联合基金资助数值预报模式关键技术、灾害天气监测预报理论与方法和人工智能气象应用技术三个核心领域,共接收申请64项,其中不同单位属性的合作申请占87.5%。申请书关键词分析发现,气象联合基金与地球科学部“天气及气候系统与可持续发展”领域重点项目既有较强的联系,又有明显的区别。气象联合基金评审过程与地球科学部常规重点基金评审过程相似。经过通讯评审和会评,共资助14项重点支持项目,资助率21.9%,平均资助强度264.6万元/项,年均资助强度超过了地球科学部常规重点项目的资助强度。 展开更多
关键词 多元投入 气象联合基金 大气科学 国家需求
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Simulated Sensitivity of Ozone Generation to Precursors in Beijing during a High O_(3) Episode 被引量:7
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作者 Meng CUI Xingqin AN +5 位作者 Li XING Guohui LI Guiqian TANG jianjun he Xin LONG Shuman ZHAO 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2021年第7期1223-1237,共15页
This study uses the WRF-Chem model combined with the empirical kinetic modeling method(EKMA curve)to study the compound pollution event in Beijing that happened in 13−23 May 2017.Sensitivity tests are conducted to ana... This study uses the WRF-Chem model combined with the empirical kinetic modeling method(EKMA curve)to study the compound pollution event in Beijing that happened in 13−23 May 2017.Sensitivity tests are conducted to analyze ozone sensitivity to its precursors,and to develop emission reduction measures.The results suggest that the model can accurately simulate the compound pollution process of photochemistry and haze.When VOCs and NOx were reduced by the same proportion,the effect of O_(3)reduction at peak time was more obvious,and the effect during daytime was more significant than at night.The degree of change in ozone was peak time>daytime average.When reducing or increasing the ratio of precursors by 25%at the same time,the effect of reducing 25%VOCs on the average ozone concentration reduction was most significant.The degree of change in ozone decreased with increasing altitude,the location of the ozone maximum change shifted westward,and its range narrowed.As the altitude increases,the VOCs-limited zone decreases,VOCs sensitivity decreases,NOx sensitivity increases.The controlled area changed from near-surface VOCs-limited to high-altitude NOx-limited.Upon examining the EKMA curve,we have found that suburban and urban are sensitive to VOCs.The sensitivity tests indicate that when VOCs in suburban are reduced about 60%,the O_(3)-1h concentration could reach the standard,and when VOCs of the urban decreased by about 50%,the O_(3)-1h concentration could reach the standard.Thus,these findings could provide references for the control of compound air pollution in Beijing. 展开更多
关键词 Ozone(O_(3)) Sensitivity of ozone to its precursors WRF-Chem model EKMA BEIJING
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高能聚束微波热疗联合沙培林胸腔注射治疗恶性胸水(英文) 被引量:2
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作者 Lingqin Song jianjun he +5 位作者 Xijing Wang Hongbing Ma Shuqun Zhang Zhijun Dai Baofeng Wang Xiaobin Ma 《The Chinese-German Journal of Clinical Oncology》 CAS 2011年第2期77-80,共4页
Objective:The aim of the study was to evaluate the efficacy and toxicity of high power focused-beam microwave hyperthermia with intrapleural injection of Shapeilin for patients with malignant hydrothorax.Methods:Fifty... Objective:The aim of the study was to evaluate the efficacy and toxicity of high power focused-beam microwave hyperthermia with intrapleural injection of Shapeilin for patients with malignant hydrothorax.Methods:Fifty-eight patients with malignant hydrothorax were divided into group A and group B randomly.All patients underwent indwelling pleural catheter and were treated by intrapleural injection of Shapeilin once three days.Treatment was composed of 3 times injection.Patients of group B received high power focused-beam microwave hyperthermia after injection of Shapeilin.Results:The response rate of group B(79.3%) was higher than that of group A(48.3%)(P < 0.05).Incidence of main adverse reactions,associated with Shapeilin,of two groups including fever and thoracodynia were similar(P > 0.05).Patients of group B didn't encounter severe toxicities of microwave hyperthermia.Conclusion:High power focused-beam microwave hyperthermia combined with intrapleural injection of Shapeilin is effective and tolerable for patients with malignant hydrothorax. 展开更多
关键词 注射治疗 微波热疗 聚焦光束 高功率 患者 胸水 恶性 腔内
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54例腹腔镜直肠癌经腹超低位吻合治疗分析 被引量:1
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作者 陈轩 何建军 +3 位作者 陈旺盛 王新 李宗林 杨庆强 《中国肿瘤临床》 CAS CSCD 北大核心 2019年第18期953-956,共4页
目的:探讨腹腔镜直肠癌经腹手术超低位吻合保肛的安全性和可行性。方法:回顾性分析2014年7月至2017年6月西南医科大学附属医院收治的54例行腹腔镜直肠癌根治、超低位吻合患者的临床资料,观察并分析术后疗效。结果:所有患者顺利完成手术... 目的:探讨腹腔镜直肠癌经腹手术超低位吻合保肛的安全性和可行性。方法:回顾性分析2014年7月至2017年6月西南医科大学附属医院收治的54例行腹腔镜直肠癌根治、超低位吻合患者的临床资料,观察并分析术后疗效。结果:所有患者顺利完成手术,无中转开腹及手术死亡病例。平均手术时间(165±31)min,术中出血(12±5)mL。本组患者未常规进行预防性造瘘。术后发生吻合口出血2例(3.7%),吻合口漏3例(5.6%),均经保守治疗痊愈。术后患者排尿功能、性功能保持良好,术后一年时绝大部分患者肛门控制排便功能满意,术后随访两年以上均无局部复发,也无死亡病例,但手术一年后有3例患者出现肝脏转移。结论:腹腔镜直肠癌经腹超低位吻合近期效果良好,远期效果有待进一步观察。 展开更多
关键词 腹腔镜 直肠癌 超低位吻合
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Multi-Scale Superhydrophobic Anti-Icing Coating for Wind Turbine Blades 被引量:1
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作者 Jiangyong Bao jianjun he +4 位作者 Biao Chen Kaijun Yang Jun Jie Ruifeng Wang Shihao Zhang 《Energy Engineering》 EI 2021年第4期947-959,共13页
As a surface functional material,super-hydrophobic coating has great application potential in wind turbine blade anti-icing,self-cleaning and drag reduction.In this study,ZnO and SiO2 multi-scale superhydrophobic coat... As a surface functional material,super-hydrophobic coating has great application potential in wind turbine blade anti-icing,self-cleaning and drag reduction.In this study,ZnO and SiO2 multi-scale superhydrophobic coatings with mechanical flexibility were prepared by embedding modified ZnO and SiO2 nanoparticles in PDMS.The prepared coating has a higher static water contact angle(CA is 153°)and a lower rolling angle(SA is 3.3°),showing excellent super-hydrophobicity.Because of its excellent superhydrophobic ability and micro-nano structure,the coating has good anti-icing ability.Under the conditions of−10C and 60%relative humidity,the coating can delay the freezing time by 1511S,which is 10.7 times slower than the normal freezing time.More importantly,due to the mechanical properties provided by SiO2 and the synergistic effect of micro-nano particles,the coating has excellent mechanical durability.After 10 wear tests,the contact angle of the coating is still as high as 141°and the rolling angle is 6.8°.This research provides a theoretical reference for the preparation of a mechanically stable coating with a simple preparation process,as well as a basic research on the anti-icing behavior of the coating. 展开更多
关键词 Mechanical flexibility ZnO SIO2 MULTI-SCALE SUPERHYDROPHOBIC
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Temperature Prediction of Aluminum Alloy Work-Pieces in Aging Furnaces Based on Improved Case-Based Reasoning 被引量:1
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作者 Qi Zhu Ling Shen +1 位作者 jianjun he Weihua Gui 《International Journal of Nonferrous Metallurgy》 2017年第4期47-59,共13页
The temperature of aluminum alloy work-pieces in the aging furnace directly affects the quality of aluminum alloy products. Since the temperature of aluminum alloy work-pieces cannot be measured directly, a temperatur... The temperature of aluminum alloy work-pieces in the aging furnace directly affects the quality of aluminum alloy products. Since the temperature of aluminum alloy work-pieces cannot be measured directly, a temperature prediction model based on improved case-based reasoning (CBR) method is established to realize the online measurement of the work-pieces temperature. More specifically, the model is constructed by an advanced case-based reasoning method in which a state transition algorithm (STA) is firstly used to optimize the weights of feature attributes. In other words, STA is utilized to find the suitable attribute weights of the CBR model that can improve the accuracy of the case retrieval process. Finally, the CBR model based on STA (STCBR) was applied to predict the temperature of aluminum alloy work-pieces in the aging furnace. The results of the experiments indicated that the developed model can realize high-accuracy prediction of work-pieces temperature and it has good application prospects in the industrial field. 展开更多
关键词 Prediction Model ALUMINUM Alloy Case-Based REASONING State Transition Algorithm AGING FURNACE
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老年乳腺癌术后多西紫杉醇联合环磷酰胺辅助化疗的毒副作用研究(英文)
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作者 Lingqin Song Yinbin Zhang +4 位作者 jianjun he Xijing Wang Hongbing Ma Wentao Xi Liang Liang 《The Chinese-German Journal of Clinical Oncology》 CAS 2011年第7期391-393,共3页
Objective: The aim of this study was to investigate the side effects of docetaxel with cyclophosphamide as postoperative adjuvant chemotherapy for elderly breast cancer patients. Methods: Thirty-six operable elderly b... Objective: The aim of this study was to investigate the side effects of docetaxel with cyclophosphamide as postoperative adjuvant chemotherapy for elderly breast cancer patients. Methods: Thirty-six operable elderly breast cancer patients at intermediate risk based on the St Gallen risk classification underwent modified radical mastectomy and then were given four cycles of TC regimen (docetaxel 75 mg/m2 i.v. on day 1; cyclophosphamide 600 mg/m2 i.v. on day 1; every 21 days ). Primary prophylaxis granulocyte colony stimulating factor (G-CSF) 200μg i.h. was administered on day 4-6. Results: The main side effect was neutropenia. Grade 3 neutropenia developed in 36.1% and G4 in 19.4%, respectively. Most of the other side effects were G1-2. Dose reduction occurred in 11.1% patients. The completion rate of chemotherapy was 100%. Conclu-sion: Docetaxel with cyclophosphamide as postoperative adjuvant chemotherapy regimen with G-CSF primary prophylaxis is tolerable for elderly patients in general good condition. 展开更多
关键词 多西紫杉醇 癌症患者 环磷酰胺 副作用 乳腺癌 化疗 老年 粒细胞集落刺激因子
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超晶格中的谐振声光互作用
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作者 jianjun he Jacques Sapriel 陈焕林 《压电与声光》 CSCD 北大核心 1990年第4期58-61,共4页
这里首次报道了对于接近布喇格偏转条件的光波长在界面上超晶格的显著声光性能.由于在相位匹配状态下逆点阵矢量的帮助,使超晶格中光波和超声波之间的共线耦合成为可能.同时,由于超晶格中光学谐振效应,大大提高了衍射效率.提出了以半导... 这里首次报道了对于接近布喇格偏转条件的光波长在界面上超晶格的显著声光性能.由于在相位匹配状态下逆点阵矢量的帮助,使超晶格中光波和超声波之间的共线耦合成为可能.同时,由于超晶格中光学谐振效应,大大提高了衍射效率.提出了以半导体及超晶格结构为基的声光器件,这种器件的效率很高,取数快速而且结构紧凑. 展开更多
关键词 声光作用 超晶格 谐振
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Modeling study on the roles of the deposition and transport of PM_(2.5) in air quality changes over central-eastern China
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作者 Lei Zhang jianjun he +11 位作者 Sunling Gong Xiaomei Guo Tianliang Zhao Huizheng Che Hong Wang Chunhong Zhou Jingyue Mo Ke Gui Yu Zheng Lei Li Junting Zhong Xiaoye Zhang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2023年第1期535-544,共10页
The role of PM_(2.5)(particles with aerodynamic diameters≤_(2.5)μm)deposition in air quality changes over China remains unclear.By using the three-year(2013,2015,and 2017)simulation results of the WRF/CUACE v1.0 mod... The role of PM_(2.5)(particles with aerodynamic diameters≤_(2.5)μm)deposition in air quality changes over China remains unclear.By using the three-year(2013,2015,and 2017)simulation results of the WRF/CUACE v1.0 model from a previous work(Zhang et al.,2021),a non-linear relationship between the deposition of PM_(2.5)and anthropogenic emissions over central-eastern China in cold seasons as well as in different life stages of haze events was unraveled.PM_(2.5)deposition is spatially distributed differently from PM_(2.5)concentrations and anthropogenic emissions over China.The North China Plain(NCP)is typically characterized by higher anthropogenic emissions compared to southern China,such as the middlelow reaches of Yangtze River(MLYR),which includes parts of the Yangtze River Delta and the Midwest.However,PM_(2.5)deposition in the NCP is significantly lower than that in the MLYR region,suggesting that in addition to meteorology and emissions,lower deposition is another important factor in the increase in haze levels.Regional transport of pollution in central-eastern China acts as a moderator of pollution levels in different regions,for example by bringing pollution from the NCP to the MLYR region in cold seasons.It was found that in typical haze events the deposition flux of PM_(2.5)during the removal stages is substantially higher than that in accumulation stages,with most of the PM_(2.5)being transported southward and deposited to the MLYR and Sichuan Basin region,corresponding to a latitude range of about 24°N-31°N. 展开更多
关键词 PM_(2.5) DEPOSITION Regional transport China WRF/CUACE v1.0 model
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Dual Rolling Circle Amplification- Assisted Single-Particle Fluorescence Profiling of Exosome Heterogeneity for Discriminating Lung Adenocarcinoma from Pulmonary Nodules
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作者 Yan Zhou Haoxiang Li +2 位作者 Min Hou jianjun he Jian-Hui Jiang 《CCS Chemistry》 CSCD 2023年第4期947-957,共11页
Exosomes secreted by tumor cells carry abundant molecular biomarkers that reflect the status of their originating cells.These tumor-derived exosomes(TDEs)have emerged as attractive diagnostic targets.However,the ident... Exosomes secreted by tumor cells carry abundant molecular biomarkers that reflect the status of their originating cells.These tumor-derived exosomes(TDEs)have emerged as attractive diagnostic targets.However,the identification and characterization of highly heterogeneous TDEs remain practically challenging.Here,we report a dual rolling circle amplification(DRCA)-assisted approach for the selective encapsulation of single TDEs for fluorescence microscopic and flow cytometric analysis.TDEs have been targeted by aptamers that recognized their surface tumor marker and exosomal marker CD63,following DRCA that produced entangling polymeric DNA chains,resulting in facile particle enlargement that allows single-particle fluorescence profiling of exosome heterogeneity.We have demonstrated the use of a dual-marker positive ratio for exosome differentiation and applied division and multiplication operations for normalized andmagnified marker heterogeneity analysis.We further applied this assay to distinguish lung adenocarcinoma and pulmonary nodule patients and found an accuracy of 90%.We anticipate promising transformations of this straightforward assay into clinically implantable diagnostic methods. 展开更多
关键词 rolling circle amplification EXOSOMES SINGLE-PARTICLE fluorescence analysis cancer diagnosis
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The TripleSat constellation:a new geospatial data service model 被引量:1
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作者 Qiang Wen jianjun he +7 位作者 Shengyong Guan Ting Chen Yin Hu Wenbin Wu Feng Liu Yuexia Qiao Suet Yheng Kok Samuel Yeong 《Geo-Spatial Information Science》 SCIE EI CSCD 2017年第2期163-173,共11页
With the increase of different sensors,applications and customers,the demand from data providers and users is for a new geospatial data service model,which supports low cost,high dexterity,and which would provide a co... With the increase of different sensors,applications and customers,the demand from data providers and users is for a new geospatial data service model,which supports low cost,high dexterity,and which would provide a comprehensive service.Based on such requirements and demands,the 21AT TripleSat constellation terminal and data delivery and management system has been developed by a Beijing based high-tech enterprise,Twenty First Century Aerospace Technology Co.,Ltd.(21AT).The company is the first commercial Earth observation satellite operator and service provider in China.This new geospatial data service model allows the user to directly access multi-source satellite data,manage the data order,and carry out automatic massive data production and delivery.The solution also implements safe and hierarchical user management,statistical data analysis,and automatic information reports.In addition,a mobile application is also available for users to easily access system functions.This new geospatial solution has already been successfully applied and installed in many customer sites in China,and is now available globally for international clients interested in fast geospatial solutions.It enables the success of customers’operational services.Besides providing TripleSat Constellation images,the multi-source data access system also allows the users to access other satellite data sources,based on customized agreement.This paper describes and discusses this new geospatial data service model. 展开更多
关键词 Geospatial data service model 21AT TripleSat constellation geospatial instant service system
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Effect of traffic restriction on atmospheric particle concentrations and their size distributions in urban Lanzhou, Northwestern China 被引量:2
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作者 Suping Zhao Ye Yu +2 位作者 Na Liu jianjun he Jinbei Chen 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2014年第2期362-370,共9页
During the 2012 Lanzhou International Marathon, the local government made a significant effort to improve traffic conditions and air quality by implementing traffic restriction measures. To evaluate the direct effect ... During the 2012 Lanzhou International Marathon, the local government made a significant effort to improve traffic conditions and air quality by implementing traffic restriction measures. To evaluate the direct effect of these measures on urban air quality, especially particle concentrations and their size distributions, atmospheric particle size distributions (0.5-20μm) obtained using an aerodynamic particle sizer (model 3321, TSI, USA) in June 2012 were analyzed. It was found that the particle number, surface area and volume concentrations for size range 0.5-10 μm were (15.0±2.1) cm-3, (11.8±2.6) μm2/cm3 and (1.9±0.6) μm2/cm3, respectively, on the traffic-restricted day (Sunday), which is 63.2%, 53.0% and 47.2% lower than those on a normal Sunday. For number and surface area concentrations, the most affected size range was 0.5-0.7 and 0.5-0.8 μm, respectively, while for volume concentration, the most affected size ranges were 0.5-0.8, 1.7-2.0 and 5.0-5.4 μm. Number and volume concentrations of particles in size range 0.5-1.0μm correlated well with the number of non-CNG (Compressed Natural Gas) powered vehicles, while their correlation with the number of CNG-powered vehicles was very low, suggesting that reasonable urban traffic controls along with vehicle technology improvements could play an important role in improving urban air quality. 展开更多
关键词 traffic restriction particle concentration size distribution urban air quality
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Influences of Meteorological Conditions on Interannual Variations of Particulate Matter Pollution during Winter in the Beijing–Tianjin–Hebei Area
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作者 jianjun he Sunling GONG +9 位作者 Hongli LIU Xingqin AN Ye YU Suping ZHAO Lin WU Congbo SONG Chunhong ZHOU Jie WANG Chengmei YIN Lijuan YU 《Journal of Meteorological Research》 SCIE CSCD 2017年第6期1062-1069,共8页
To investigate the interannual variations of particulate matter (PM) pollution in winter, this paper examines the pollution characteristics of PM with aerodynamic diameters of less than 2.5 and 10 μm (i.e., PM2.5 ... To investigate the interannual variations of particulate matter (PM) pollution in winter, this paper examines the pollution characteristics of PM with aerodynamic diameters of less than 2.5 and 10 μm (i.e., PM2.5 and PM10), and their relationship to meteorological conditions over the Beijing municipality, Tianjin municipality, and Hebei Province--an area called Jing-Jin-Ji (JJJ, hereinafter)-in December 2013-16. The meteorological conditions during this period are also analyzed. The regional average concentrations of PM2.5 (PM10) over the JJJ area during this period were 148.6 (236.4), 100.1 (166.4), 140.5 (204.5), and 141.7 (203.1) μg m^-3, respectively. The high occurrence frequencies of cold air outbreaks, a strong Siberian high, high wind speeds and boundary layer height, and low temperature and relative humidity, were direct meteorological causes of the low PM concentration in December 2014. A combined analysis of PM pollution and meteorological conditions implied that control measures have resulted in an effective improvement in air quality. Using the same emissions inventory in December 2013-16, a modeling analysis showed emissions of PM2.5 to decrease by 12.7%, 8.6%, and 8.3% in December 2014, 2015, and 2016, respectively, each compared with the previous year, over the JJJ area. 展开更多
关键词 particulate matter pollution local meteorological conditions circulation types Siberian high
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基于大气科学学科发展特点,解读项目分类评审改革新举措 被引量:16
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作者 刘哲 何建军 郭郁葱 《科学通报》 EI CAS CSCD 北大核心 2021年第2期187-192,共6页
当前新一轮科技革命蓬勃兴起,科学研究范式正在发生深刻变革,促进了各学科之间的交叉、融合.与此同时,国际形势的新变化,加剧了国家间日趋激烈的科技竞争.在这一背景下,国家自然科学基金委员会(下文简称“基金委”)认真贯彻党中央关于... 当前新一轮科技革命蓬勃兴起,科学研究范式正在发生深刻变革,促进了各学科之间的交叉、融合.与此同时,国际形势的新变化,加剧了国家间日趋激烈的科技竞争.在这一背景下,国家自然科学基金委员会(下文简称“基金委”)认真贯彻党中央关于科技创新和基础研究的重大决策,系统部署了“明确资助导向、完善评审机制、优化学科布局”三大任务,旨在深化新时代科学基金改革,构建理念先进、制度规范、公正高效的科学基金治理体系[1]. 展开更多
关键词 科学基金 科学研究范式 项目分类 大气科学 国家自然科学基金委员会 构建理念 学科布局 三大任务
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宇宙中铁以上的重核是如何合成的? 被引量:5
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作者 何建军 郭冰 +1 位作者 柳卫平 赵刚 《科学通报》 EI CAS CSCD 北大核心 2018年第24期2429-2439,共11页
针对21世纪尚未解决的11个重大物理问题之三,即"宇宙中从铁到铀的元素是如何产生的?"进行了系统的阐述,包括问题提出的背景和重要性、主要研究内容、国内外进展以及将来的发展趋势.介绍了产生宇宙中比铁重的元素(简称为超铁元... 针对21世纪尚未解决的11个重大物理问题之三,即"宇宙中从铁到铀的元素是如何产生的?"进行了系统的阐述,包括问题提出的背景和重要性、主要研究内容、国内外进展以及将来的发展趋势.介绍了产生宇宙中比铁重的元素(简称为超铁元素)的几个主要核合成过程,并总结了相关的研究目标.目前,尚需要精确测量天体核合成路径上关键核素的质量、寿命以及相关核反应的反应截面或者天体物理反应率等核物理输入量;开展天体元素或者同位素丰度的观测研究,以及星际X和γ射线等的卫星观测;发展天体物理模型以及核物理理论模型,最终将可靠的核物理输入量、核天体物理理论模型和天文观测数据相结合,以探索和解决宇宙中超铁元素的来源问题. 展开更多
关键词 核天体物理 超铁元素 核反应 核合成 元素丰度观测
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2020年度大气科学领域项目评审与资助成果简析 被引量:11
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作者 何建军 郭郁葱 +2 位作者 刘哲 吴捷 李莉 《地球科学进展》 CAS CSCD 北大核心 2020年第11期1201-1210,共10页
介绍了2020年度国家自然科学基金委员会地球科学部五处(大气学科)改革工作;分析了2020年度五处所管理的面上项目、青年科学基金项目、地区科学基金项目、重点项目、国家杰出青年科学基金项目和优秀青年科学基金项目等的申请情况,以及项... 介绍了2020年度国家自然科学基金委员会地球科学部五处(大气学科)改革工作;分析了2020年度五处所管理的面上项目、青年科学基金项目、地区科学基金项目、重点项目、国家杰出青年科学基金项目和优秀青年科学基金项目等的申请情况,以及项目评审和资助情况;总结了2019年度五处结题项目完成情况。 展开更多
关键词 基金资助导向 分类评审改革 资助成果分析 大气科学
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锦屏深地核天体物理实验(JUNA)的首个结果:^(25)Mg(p,γ)^(26)Al反应92 keV共振的精确测量 被引量:8
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作者 苏俊 张昊 +49 位作者 李志宏 Paolo Ventura 李云居 李二涛 陈晨 谌阳平 连钢 郭冰 李鑫悦 张立勇 何建军 盛耀德 陈银吉 王泺欢 张龙 曹富强 南巍 南威克 李歌星 宋娜 崔保群 陈立华 马瑞刚 张智程 焦韬瑜 高丙水 唐晓东 吴启 李家庆 孙良亭 王硕 颜胜权 廖俊辉 王友宝 曾晟 南丁 樊启文 祁宁春 孙文良 郭绪元 张鹏 陈云华 周永 周济芳 何金荣 商长松 李名川 程建平 柳卫平 锦屏深地核天体物理合作组 《Science Bulletin》 SCIE EI CSCD 2022年第2期125-132,M0003,共9页
银河系星际介质中的^(26)Al衰变发射的1.809 MeVγ射线是γ天文学的主要观测对象之一,是银河系中正在进行核合成的关键证据,也为核合成理论与天文观测进行比较提供一个重要基准.在大质量恒星氢燃烧中,^(26)Al主要通过^(25)Mg(p,γ)^(26... 银河系星际介质中的^(26)Al衰变发射的1.809 MeVγ射线是γ天文学的主要观测对象之一,是银河系中正在进行核合成的关键证据,也为核合成理论与天文观测进行比较提供一个重要基准.在大质量恒星氢燃烧中,^(26)Al主要通过^(25)Mg(p,γ)^(26)Al反应产生,因此该反应在1.809 MeVγ射线研究中起着重要的作用.在天体环境温度为0.1 GK左右时,^(25)Mg(p,γ)^(26)Al天体物理反应率主要由92 keV共振俘获过程决定.作为在中国锦屏地下实验室(CJPL)中锦屏核天体物理实验(JUNA)装置上进行的首个实验,本工作对^(25)Mg(p,γ)^(26)Al反应的92 keV共振进行了精确的实验测量,得到了该共振的共振强度为ωγ=(3.80.3)10^(-10) eV,基态分支比为f0=0.660.04.与之前的工作相比,本工作大大提高了92 keV共振数据的精度.基于测量的92 keV共振参数和以前的间接测量结果,得到了精度最高的^(25)Mg(p,γ)^(26)Al天体物理反应率.结果表明,在0.1 GK左右时,新的反应率比REACLIB数据库中采用的反应率大2.4倍,这将导致^(26)Al和宇宙1.809 MeVγ射线的产额提高.同时,新反应率也将对理解太阳系的形成、球状星团的元素丰度反相关等问题提供重要的数据支撑. 展开更多
关键词 星际介质 核合成 间接测量 氢燃烧 天文观测 球状星团 观测对象
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A proposed direct measurement of cross section at Gamow window for key reaction 19F(p,α) 16O in Asymptotic Giant Branch stars with a planned accelerator in CJPL 被引量:3
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作者 jianjun he ShiWei Xu +16 位作者 ShaoBo Ma Jun Hu LiYong Zhang ChangBo Fu NingTao Zhang Gang Lian Jun Su YunJu Li ShengQuan Yan YangPing Shen SuQing Hou BaoLu Jia Tao Zhang XiaoPeng Zhang Bing Guo Shigeru Kubono WeiPing Liu 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2016年第5期76-82,共7页
In 2014, the National Natural Science Foundation of China(NSFC) approved the Jinping Underground Nuclear Astrophysics laboratory(JUNA) project, which aims at direct cross-section measurements of four key stellar nucle... In 2014, the National Natural Science Foundation of China(NSFC) approved the Jinping Underground Nuclear Astrophysics laboratory(JUNA) project, which aims at direct cross-section measurements of four key stellar nuclear reactions right down to the Gamow windows. In order to solve the observed fluorine overabundances in Asymptotic Giant Branch(AGB) stars, measuring the key ^(19)F( p,α)^(16)O reaction at effective burning energies(i.e., at Gamow window) is established as one of the scientific research sub-projects. The present paper describes this sub-project in details, including motivation, status, experimental setup, yield and background estimation, aboveground test, as well as other relevant reactions. 展开更多
关键词 核反应截面测量 直接测量 伽莫夫 国家自然科学基金委员会 恒星 巨星 窗户 加速器
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Laser-driven plasma collider for nuclear studies 被引量:2
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作者 Changbo Fu Jie Bao +16 位作者 Liming Chen jianjun he Long Hou Liang Li Yanfei Li Yutong Li Guoqian Liao Yongjoo Rhee Yang Sun Shiwei Xu Dawei Yuan Xiaopeng Zhang Gang Zhao Jiarui Zhao Baojun Zhu Jianqiang Zhu Jie Zhang 《Science Bulletin》 SCIE EI CAS CSCD 2015年第13期1211-1213,共3页
A novel method of initiating nuclear fusion reactions in a full plasma environment was suggested, and a proof-of-concept experiment was carried out with the D t D ! n t3 He reaction. In this new approach, two plasma j... A novel method of initiating nuclear fusion reactions in a full plasma environment was suggested, and a proof-of-concept experiment was carried out with the D t D ! n t3 He reaction. In this new approach, two plasma jets generated by high-intensity lasers collide headon-head. The center-of-mass energy of the nuclei increases accordingly, and therefore, reaction products can be significantly enhanced, especially in the sub-Coulomb barrier ranges. As a result of the fusion reaction, up to 7:6 105 neutrons had been observed. This new type of ‘‘plasma collider'' could provide an innovative tool to study nuclear reactions under astrophysical conditions. 展开更多
关键词 等离子体环境 对撞机 激光驱动 核研究 核聚变反应 等离子体射流 质量中心 反应产物
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