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Stepped-up development of accelerator mass spectrometry method for the detection of ^(60)Fe with the HI-13 tandem accelerator

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Nuclear Science and Techniques 2024年第4期35卷 136-143页

作者： Yang Zhang Sheng-quan Yan Ming He qing-Zhang Zhao Wen-Hui Zhang Chao-Xin Kan Jian-Ming Zhou Kang-Ning Li Xiao-Fei Wang Jian-Cheng Liu Zhao-Hua Peng Zhuo Liang Ai-Ling Li Jian Zheng qi-Wen Fan Yun-ju Li You-Bao Wang Zhi-Hong Li Yang-Ping Shen Ding Nan Wei Nan Yu-qiang Zhang Jia-Ying-Hao Li jun-Wen Tian Jiang-Lin Hou Chang-Xin Guo Zhi-Cheng Zhang Ming-Hao Zhu Yu-Wen Chen Yu-Chen Jiang Tao Tian Jin-Long Ma Yi-Hui Liu Jing-Yu Dong Run-Long Liu Mei-Yue-Nan Ma Yong-Shou Chen Wei-Ping Liu Bing Guo China Institute of Atomic Energy P.O.Box 275(10)Beijing 102413China College of Science Southern University of Science and TechnologyShenzhen 518055China School of Physics Xi’an Jiaotong UniversityXi’an 710049China

The Moon provides a unique environment for investigating nearby astrophysical events such as *** samples retain valuable information from these events,via detectable long-lived“fingerprint”radionuclides such as^(60)*** this work,we stepped up the development of an accelerator mass spectrometry(AMS)method for detecting^(60)Fe using the HI-13tandem accelerator at the China Institute of Atomic Energy(CIAE).Since interferences could not be sufficiently removed solely with the existing magnetic systems of the tandem accelerator and the following q3D magnetic spectrograph,a Wien filter with a maximum voltage of±60 kV and a maximum magnetic field of 0.3 T was installed after the accelerator magnetic systems to lower the detection background for the low abundance nuclide^(60)Fe.A 1μm thick Si_(3)N_(4) foil was installed in front of the q3D as an energy *** particle detection,a multi-anode gas ionization chamber was mounted at the center of the focal plane of the ***,an^(60)Fe sample with an abundance of 1.125×10^(-10)was used to test the new AMS *** results indicate that^(60)Fe can be clearly distinguished from the isobar^(60)*** sensitivity was assessed to be better than 4.3×10^(-14)based on blank sample measurements lasting 5.8 h,and the sensitivity could,in principle,be expected to be approximately 2.5×10^(-15)when the data were accumulated for 100 h,which is feasible for future lunar sample measurements because the main contaminants were sufficiently separated.

关键词： Accelerator mass spectrometry Wien filter Isobar separation Supernovae Chang'e-5 lunar samples

Effect of CaF_(2) and CaO/Al_(2)O_(3) on viscosity and structure of TiO_(2)-bearing slag for electroslag remelting

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Journal of Iron and Steel Research International 2021年第12期28卷 1541-1550页

作者： Jian-tao ju Kang-shuai Yang Zhi-hong Zhu Yue Gu Li-zhong Chang School of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an710055ShaanxiChina Shaanxi Engineering Research Center of Metallurgical Xi’an710055ShaanxiChina School of Metallurgy Engineering Anhui University of TechnologyMa’anshan243002AnhuiChina

The relationship between the viscosity and structure of CaF_(2)-CaO-Al_(2)O_(3)-MgO-TiO_(2)slag with different CaF_(2)contents and CaO/Al_(2)O_(3)ratios was studied using the rotating cylinder method,Fourier transform infrared spectroscopy,and Raman *** activity coefficients of CaF_(2)and the CaO/Al_(2)O_(3)ratio were determined to understand the correlation between viscosity and structure of the *** results suggest that the slag viscosity reduces gradually with an increase in CaF_(2)content from 14.1 to 28.1 wt.%or CaO/Al_(2)O_(3)ratio from 0.9 to 1.5,and correspondingly apparent activation energy for viscous flow *** addition of CaF_(2)does not change the structure of the molten slag;however,the relaxation effect of the anionic species and the hindrance effect of the cationic species are promoted by substituting part of the non-bridging oxygens(NBO)with F−ions from CaF_(2),which is attributed to the formation of NBO-Ca^(2+)-F−and NBO-Ca^(2+)-NBO,***,as the CaO/Al_(2)O_(3)ratio increases,some of the q4 units in the aluminate structure are depolymerized into q2 units,so that the relative strength of the Al-O-Al linkage decreases,and the relative fraction of Ti2O64−chains increases,whereas that of O-Ti-O chains decreases slightly,resulting in depolymerization on the slag ***,the effect of the CaO/Al_(2)O_(3)ratio on the structure was greater than that of CaF_(2)because of the greater depolymerization *** variation in the activity can indirectly explain the relationship between the viscosity and structure of the aluminate structural units based on thermodynamic analysis.

关键词： Viscosity TiO_(2)-bearing slag Fourier transform infrared spectroscopy Raman spectrum Thermodynamic

Validation and error analysis of wave-modifi ed ocean surface currents in the northwestern Pacifi c Ocean

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Journal of Oceanology and Limnology 2022年第4期40卷 1289-1303页

作者： Zhenli HUI Ying LI Jia SUN Long YU Xia ju Xuejun XIONG First Institute of Oceanography and Key Laboratory of Marine Science and Numerical ModelingMinistry of Natural ResourcesQingdao 266061China Laboratory for Regional Oceanography and Numerical Modeling Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China Shandong Key Laboratory of Marine Science and Numerical Modeling Qingdao 266061China

By incorporating the wave-induced Coriolis-Stokes forcing into the classical Ekman layer,the wave-modifi ed ocean surface currents in the northwestern Pacifi c Ocean were ***,the ocean surface currents are the combination of classical Ekman current from the cross-calibrated multi-platform(CCMP)wind speed,geostrophic current from the mean absolute dynamic topography(MADT),and wave-induced current based on the European Centre for Medium-Range Weather Forecasts(ECMWF)Interim Re-Analysis(ERA-Interim)surface wave *** functions are introduced in the Ekman current formulation as *** with in-situ data from Lagrangian drifters in the study area and Kuroshio Extension Observatory(KEO)observations at 32.3°N,144.6°E,and 15-m depth indicate that wave-modifi ed ocean surface currents provide accurate time means of zonal and meridional currents in the northwestern Pacifi c *** shows that the wave-modifi ed currents are quite consistent with the Lagrangian drifter observations for the period 1993-2017 in the deep *** correlation(root mean square error,RMSE)is 0.96(1.45 cm/s)for the zonal component and 0.90(1.07 cm/s)for the meridional ***,wave-modifi ed currents underestimate the Lagrangian drifter velocity in strong current and some off shore regions,especially in the regions along the Japan coast and the southeastern ***’s more,the wave-modifi ed currents overestimate the pure Eulerian KEO current which does not consider the impact of waves,and the zonal(meridional)correlation and RMSE are 0.95(0.90)and 11.25 cm/s(12.05 cm/s)*** comparisons demonstrate that our wave-modifi ed ocean surface currents have high precision and can describe the real-world ocean in the northwestern Pacifi c Ocean accurately and intuitively,which can provide important routes to calculate ocean surface currents on large spatial scales.

关键词： ocean surface current Ekman current geostrophic current Stokes drift

基于UPLC-q TOF-MSE技术的藤黄健骨丸指纹图谱建立及共有峰鉴定

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应用化学 2024年第3期41卷 437-444页

作者：谢东胡健楠李念杨桔黄青皮子凤郑飞戴雨霖越皓长春中医药大学吉林省人参科学研究院长春130117 长春人民药业集团有限公司长春130033

建立藤黄健骨丸高效液相色谱(HPLC)指纹图谱,完善产品质量标准。采用Waters Symmetry C18(150 mm×2.1 mm,3.5μm)色谱柱;流速为0.4 mL/min;进样量为2μL;紫外检测波长为260 nm;在柱温30℃下以0.1%甲酸水(A)和0.1%甲酸乙腈(B)为流动相... 详细信息

建立藤黄健骨丸高效液相色谱(HPLC)指纹图谱,完善产品质量标准。采用Waters Symmetry C18(150 mm×2.1 mm,3.5μm)色谱柱;流速为0.4 mL/min;进样量为2μL;紫外检测波长为260 nm;在柱温30℃下以0.1%甲酸水(A)和0.1%甲酸乙腈(B)为流动相进行梯度洗脱。利用“中药色谱指纹图谱相似度评价系统(2012版本)”建立藤黄健骨丸指纹图谱,并分析相似度。采用液质联用技术(UPLC-q TOF-MSE),根据化合物串联质谱信息结合对照品进行了共有峰结构鉴定。共确定了10批藤黄健骨丸指纹图谱中20个共有峰,相似度均在0.95以上。基于对照品和串联质谱信息指认了共有峰中13种成分的结构,并进行了峰归属。对10批藤黄健骨丸指纹图谱共有峰的相对保留时间和相对峰面积进行了计算,结果显示各批次样品共有峰的相对保留时间和相对峰面积均比较稳定,表明它们所对应的各成分含量较为均一。采用该指纹图谱对中间体进行了相似度评价,发现中间体与成品相关性良好。该方法精密度、重复性和稳定性好,不仅可用于藤黄健骨丸成品的质量控制,还可对中间体进行检测,用于生产过程的控制。

关键词：藤黄健骨丸高效液相色谱指纹图谱液质联用

Prediction and evaluation of optimum quenching temperature and microstructure in a 1300 MPa ultra-high-strength q&P steel

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Journal of Iron and Steel Research International 2022年第2期29卷 307-315页

作者： Peng-fei Gao ju-hua Liang Wei-jian Chen Feng Li Zheng-zhi Zhao Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing100083China Beijing Laboratory of Metallic Materials and Processing for Modern Transportation Beijing100083China Key Laboratory of Materials Physics Institute of Solid State PhysicsChinese Academy of SciencesHefei230031AnhuiChina

The quenching and partitioning steel is the representative of the third generation of advanced high-strength *** effect of quenching temperature on the microstructure and mechanical property of ferrite-containing quenching and partitioning steel was studied by intercritical annealing quenching and partitioning *** preparing a test steel with a tensile strength of 1300 MPa and total elongation of 19%,it is found that the actual optimum quenching temperature was lower than that calculated according to the constrained carbon *** results indicate that the martensite start temperature of the austenite was overestimated when considering the diffusion of carbon *** grain size which is affected by low temperature and the existence of ferrite during intercritical annealing influenced the optimum quenching temperature.A scheme considering the diffusion of various alloying elements and austenite grain size was proposed and *** this scheme,the optimum quenching temperature of intercritically annealed quenching and partitioning steel with complex microstructures was well predicted.

关键词： quenching and partitioning Constrained carbon equilibrium Retained austenite Martensite start temperature Plasticity quenching temperature

Effect of temperature and moisture on soil organic carbon mineralization of predominantly permafrost peatland in the Great Hing'an Mountains,Northeastern China

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Journal of Environmental Sciences 2010年第7期22卷 1057-1066页

作者： Xianwei Wang Xiuzhen Li Yuanman Hu Jiujun Lv ju Sun Zongmei Li Zhifeng Wu Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China Graduate School of Chinese Academy of Sciences Beijing 100039 China Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Changchun 130012 China

Boreal peatlands represent a large global carbon pool. The relationships between carbon mineralization, soil temperature and moisture in the permafrost peatlands of the Great Hing＇an Mountains, China, were examined. The CO2 emissions were measured during laboratory incubations of samples from four sites under different temperatures （5, 10, 15, and 20℃） and moisture contents （0%, 30%, 60%, 100% water holding capacity （WHC） and completely water saturated）. Total carbon mineralization ranged from 15.51 to 112.92 mg C under the treatments for all sites. Carbon mineralization rates decreased with soil depth, increased with temperature, and reached the highest at 60% WHC at the same temperature. The calculated temperature coefficient （q10） values ranged from 1.84 to 2.51 with the soil depths and moisture. However, the values were not significantly affected by soil moisture and depth for all sites due to the different peat properties （P 〉 0.05）. We found that the carbon mineralization could be successfully predicted as a two-compartment function with temperature and moisture （R^2 〉 0.96） and total carbon mineralization was significantly affected by temperature and moisture （P 〈 0.05）. Thus, temperature and moisture would play important roles in carbon mineralization of permafrost peatlands in the Great Hing＇an Mountains, indicating that the permafrost peatlands would be sensitive to the environment change, and the permafrost peatlands would be potentially mineralized under future climate change.

关键词： Great Hing'an Mountains permafrost peatland mineralization climate change

Aggregation-induced emission luminogens for organic light-emitting diodes with a single-component emitting layer

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聚集体(英文)

聚集体(英文) 2023年第1期4卷 41-89页

作者： Jinhyo Hwang Peethani Nagaraju Min ju Cho Dong Hoon Choi Department of Chemistry Research Institute for Natural SciencesKorea UniversitySeongbuk-guSeoulRepublic of Korea

Organic light-emitting diodes(OLEDs)have garnered increasing attention as a promising candidate for application in next-generation displays and solid-state lighting *** doping technique commonly used to fabricate light-emitting layers(EMLs)of OLEDs disperses the emitting material in a host matrix to mitigate aggregation-induced quenching(ACq).Alternatively,owing to their high efficiency and ease of manufacture,nondoped OLEDs have been developed as a substitute for doped *** fabricating nondoped OLEDs,it is essential to suppress the ACq effect in the EML and efficiently utilize the generated excitons for radiative *** the discovery of aggregation-induced emission(AIE)by Tang et al.,significant work has been done to improve the stability and efficiency of nondoped OLEDs based on fluorescent AIE luminogens(AIEgens).Fluorescent AIEgens,synthesized using various molecular frameworks,such as silole,tetra/triphenylethylene,tetraphenylpyrazine,and tetraphenylbenzene,exhibit high photoluminescence quantum yields in the solid ***,many studies have reported that fluorescent AIEgen-based OLEDs have excellent external quantum efficiency and exhibit emission at various wavelengths,including deep-blue/blue/green *** the development of fluorescent AIEgens,delayed fluorescent AIEgens with efficient triplet utilization through reverse intersystem crossing and AIE properties have been adopted as ideal emitters and used in nondoped *** review systematically discusses and summarizes recent reports on the development of AIEgens for nondoped OLEDs by grouping them into fluorescent and delayed fluorescent *** purpose of this review is to provide deep insights into the design of novel AIEgens for high-performance nondoped OLEDs.

关键词： aggregation-induced emission nondoped emitting layer organic light-emitting diode

An investigation on micro pore structures and the vapor pressure mechanism of explosive spalling of RPC exposed to high temperature

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Science China(Technological Sciences) 2013年第2期56卷 458-470页

作者： ju Yang LIU HongBin TIAN KaiPei LIU JinHui WANG Li GE ZhiShun State Key Laboratory of Coal Resources and Safe Mining China University of Mining and Technology Beijing Key Laboratory of Fracture and Damage Mechanics of Rocks and Concrete China University of Mining and Technology School of Mechanics and Civil Engineering China University of Mining and Technology

Reactive powder concrete （RPC） is vulnerable to explosive spalling when exposed to high temperature. The characteristics of micro pore structure and vapor pressure of RPC are closely related to the thermal spalling. Applying mercury intrusion po- rosimetry （MIP） and scanning electron microscopy （SEM） techniques, the authors probed the characteristics of micro pore structures of plain RPC200 when heated from 20-350~C. The pore characteristics such as specific pore volume, threshold pore size and most probable pore size varying with temperatures were investigated. A vapor pressure kit was developed to measure the vapor pressure and its variation inside RPC200 at various temperatures. A thin-wall spherical pore model was proposed to ana- lyze the thermo-mechanical mechanism of spalling, by which the stresses varying with the vapor pressure q（T） and the character- istic size of wall （K） at any point of interest were determined. It is shown that the pore characteristics including specific pore volume, average pore size, threshold pore size and most probable pore size rise significantly with the increasing temperature. 200~C appears to be the threshold temperature above which the threshold pore size and the most probable pore size climb up dramatically. The increase in the specific pore volume results from the growth both in quantity and in volume of the transition pores and the capillary pores. The appearance of the explosive spalling in RPC200 is mainly attributed to being unable to form pathways in favor of releasing water steam in RPC and to thin-wall sphere domain where the vapor pressure governs the the rapid accumulation of high vapor pressures as well. The spalling is bounded through the pore model.

关键词： reactive powder concrete (RPC) high temperature spalling pore structure vapor pressure microstructures mercuryintrusion porosimetry (MIP)

Fabrication of N-CqDs@W_(18)O_(49) heterojunction with enhanced charge separation and photocatalytic performance under full-spectrum ligh irradiation

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Chinese Chemical Letters 2021年第10期32卷 3180-3184页

作者： ju Huang Jiawen Wang Zhengjia Hao Chensha Li Binsong Wang Yang qu Department of Environmental Science School of Chemistry and Materials ScienceKey Laboratory of Functional Inorganic Material ChemistryMinistry of Education of the People’s Republic of ChinaHeilongjiang UniversityHarbin 150080China

Increasing the charge separation and the utilization efficiency of sunlight are essential factors in a photocatalytic *** this study,we prepared crystalline N-CqDs@W_(18) O_(49) heterostructures,through the in situ growth of W_(18) O_(49) nanocrystals on nitrogen-doped carbon quantum dots(N-CqDs).N-CqDs@W_(18) O_(49) nanocomposites showed high activity in the photodegradation of ciprofloxacin(CIP)and methyl orange(MO).The photodegradation activity of the optimized N-CqDs@W_(18) O_(49)-5 sample was four times higher than that of W_(18) O_(49) under ultraviolet-visible(UV–vis) light *** photodegradation activity of N-CqDs@W_(18) O_(49)-5 sample was two times higher than that of W_(18) O_(49) under near-infrared(NIR) light *** enhanced photosensitivity of the nanocomposites was attributed to the promotion of charge separation by N-CqDs and the local surface plasmon resonance(LSPR) effect of W_(18) O_(49) under NIR light *** work provides a promising approach for designing and manufacturing photocatalysts with full-spectral responsiveness and improved charge separation.

关键词： Photocatalysis Full-spectrum light Tungsten oxide Localized surface plasmon resonance Nitrogen-doped carbon quantum dots