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Journal of Hydrodynamics 2008年第5期20卷 617-623页

作者： CHEN Er-yun MA Da-wei LE Gui-gao wang kai ZHAO Gai-ping School of Mechanical Engineering Nanjing University of Science and Technology Nanjing 210094 China School of Medical Instrument Shanghai university of Science and Technology Shanghai 200093 China

Highly undcrexpanded axisymmctric jet was simulated using the Runge-Kutta Discontinuous Galerkin （RKDG） finite element method, which, based on two-dimensional conservation laws, was used to solve the axisymmetric Euler equations. The computed results show that the complicated flow field structures of interest, including shock waves, slipstreams and the triple point observed in experiments could be well captured using the RKDG finite element method. Moreover, comparisons of the Mach disk location exhibit excellent agreements between the computed results and experimental measurements, indicating that this method has high capability of capturing shocks without numerical oscillation and artificial viscosity occurring near the discontinuous point.

关键词： underexpanded jct shock RKDG finite element method

A primary study on biological behavior of aluminum using^26Al-AMS

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Nuclear Science and Techniques 2016年第3期27卷 25-30页

作者： Song-Mei Qin Xiang-gao wang Xiao-Xi Lan Yun-Ting Gu Ke-Jun Dong Ming He Shan Jiang Guangxi University of Chinese Medicine Nanning 530001China GXU-NAOC Center for Astrophysics and Space Sciences Department of PhysicsGuangxi UniversityNanning 530004China Guangxi Key Laboratory for the Relativistic Astrophysics Nanning 530004China China Institute of Atomic Energy Beijing 102413China

Aluminum is concerned as a possible cause of many *** investigate the long-term A1 biokinetics and bioavailability in various kinds of Al-contained medicine and food,an accelerator mass spectrometry(AMS)based on the HI-13 tandem has been established for biological analysis with ^(26)A1(T_(1/2) = 716,000 years) as the *** this paper,the animal tracing,sample preparation procedure and ^(26)A1-AMS measurement are *** sample preparation procedure has been simplified.A high sensitivity of 5×10^(-15) for ^(26)A1/^(27)A1 has been *** phases were found before and after a break time(t_b)for the ^(26)A1 retained in blood and brain,with t_b≈8 and12 h after the ^(26)Al tracer injection,respectively.

关键词： AMS 生物学特性铝制备过程生物利用度生物动力学加速器质谱生物分析

Development and improvement of mass flux convection parameterization scheme and its applications in the seasonal climate predication model

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Chinese Science Bulletin 2003年第10期48卷 1006-1015页

作者： PING Fan, gao Shouting & wang Huijun Institute of Atmosphere Physics, Chinese Academy of Sciences, Beijing 100029, China Institute of Atmosphere Physics Chinese Academy of Sciences Beijing China

The features of Gregory cumulus parameterization scheme, which is used in British Weather Office, are researched and then this scheme is developed and improved according to the characteristics of area precipitation over China. Firstly, the influence of the large-scale convergence in lower tropopause upon cumulus convection is directly taken into account in a 揵ulk?cloud model. The organized entrainment and detrainment is considered in the model. Secondly, the initial mass flux is revised. Thirdly, the effects of subcooling water upon saturation vapour pressure are considered. Eventually, the drown-draft air is regulated. For several years, the numerical forecast of seasonal precipitation in China has been carried out by using the modified Gregory scheme. The result shows that the model with improved Gregory scheme well simulates the precipitation over China and the prediction result is good.

关键词：质量流量对流参数化季侯风应用大规模收敛对流层

A sub-block orthogonal single carrier frequency domain equalization system in fast Rayleigh fading channel

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Science China(Information Sciences) 2010年第9期53卷 1833-1847页

作者： LIU Rui*,gao XiQi* & wang WenJin National Communication Research Laboratory,Southeast University,Nanjing 210096,China 1. National Communication Research Laboratory Southeast University Nanjing 210096 China

In this paper,we analyze the frequency domain linear equalization(FDLE) of single carrier block transmission(SCBT) systems under fast fading ***,we propose a new approximating model in which the channel is assumed to be static in sub-blocks vary each *** on this model,we derive a new 2-orthogonal-sub-blocked frequency domain equalization ***,we derive the conditions of the channel under which the equalization method can be applied to the 2-orthogonal-sub-blocked *** demonstrates that the proposed method can improve the anti-Doppler ability of SC-FDLE and at the same time keep its high efficiency and low complexity.

关键词： SCBT SC-FDE LMMSE

Aggregate stability and associated C and N in a silty loam soil as affected by organic material inputs

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Journal of Integrative Agriculture 2015年第4期14卷 774-787页

作者： LONG Pan SUI Peng gao wang-sheng wang Bin-bin HUANG Jian-xiong YAN Peng ZOU Juan-xiu YAN Ling-ling CHEN Yuan-quan Circular Agriculture Research Center/College of Agronomy and Biotechnology China Agricultural University

To make recycling utilization of organic materials produced in various agricultural systems, five kinds of organic materials were applied in a field test, including crop straw （CS）, biogas residue （BR）, mushroom residue （MR）, wine residue （WR）, pig manure （PM）, with a mineral fertilizer （CF） and a no-fertilizer （CK） treatment as a control. Our objectives were： i） to quantify the effects of organic materials on soil C and N accumulation; ii） to evaluate the effects of organic materials on soil aggregate stability, along with the total organic carbon （TOC）, and N in different aggregate fractions; and iii） to assess the relationships among the organic material components, soil C and N, and C, N in aggregate fractions. The trial was conducted in Wuqiao County, Hebei Province, China. The organic materials were incorporated at an equal rate of C, and combined with a mineral fertilizer in amounts of 150 kg N ha^-1, 26 kg P ha^-1 and 124 kg K ha-1 respectively during each crop season of a wheat-maize rotation system. The inputted C quantity of each organic material treatment was equivalent to the total amount of C contained in the crop straw harvested in CS treatement in the previous season. TOC, N, water-stable aggregates, and aggregate-associated TOC and N were investigated. The results showed that organic material incorporation increased soil aggregation and stabilization. On average, the soil macroaggregate proportion increased by 14%, the microaggregate proportion increased by 3%, and mean-weight diameter （MWD） increased by 20%. TOC content followed the order of PM〉WR〉MR〉BR〉CS〉CK〉CF; N content followed the order WR〉PM〉MR〉BR〉CS〉CF〉CK. No significant correlation was found between TOC, N, and the quality of organic material. Soil silt and clay particles contained the largest part of TOC, whereas the small macroaggregate fraction was the most sensitive to organic materials. Our results indicate that PM and WR exerted better effects on soil C and N accumulation, followed by

关键词： organic materials aggregates soil organic carbon soil nitrogen stabilization

Mercury pollution and control in China

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Journal of Environmental Sciences 1991年第3期3卷 105-112页

作者： gao Dazhi, wang Jinjia and Cai JinluResearch Center for Eco-Environmental Sicences,Academia Sinica,Beijing 100083,China

Before 1970s the Second Songhua River and Ji Canal of China had been polluted seriously by mercury. During peak pollution period, mercury levels in water, sediment and fish body of these rivers were close to or even higher than that of famous Minamata Bay of Japan. Some residents who live near to the polluted rivers were affected and the methyl mercury values in their blood, hair and urine were higher than normal people obviously . Since the fish had decreased even vanished in these rivers, so the food chain that transfers mercury to human also was out off almostly. However, nervous symptoms of Minamata disease were discovered among fisherman who had eaten more fishes. This report relates the stories about the mercury pollution of the Second Songhua River and Ji Canal.

关键词： mercury pollution Minamata disease food chain.

Macro-mechanics and Microstructure of Nanomaterial-modified Geopolymer Concrete: A Comprehensive Review

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 204-214页

作者： wang Tao FAN Xiangqian gao Changsheng QU Chiyu The National Key Laboratory of Water Disaster Prevention Nanjing Hydraulic Research InstituteNanjing 210024China Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) Guangzhou 511458China School of Water Conservancy and Transportation Zhengzhou UniversityZhengzhou 450001China

We have described in detail the effects of nano-SiO_(2),nano-CaCO_(3),carbon nanotubes,and nano-Al_(2)O_(3) on geopolymer concrete from the perspectives of macro mechanics and *** existing research results show that the mechanism of nano-materials on geopolymer concrete mainly includes the filling effect,nucleation effect,and bridging effect,the appropriate amount of nano-materials can be used as fillers to reduce the porosity of geopolymer concrete,and can also react with Ca(OH)2 to produce C-S-H gel,thereby improving the mechanical properties of geopolymer *** optimum content of nano-SiO_(2) is between 1.0%and 2.0%.The optimum content of nano-CaCO_(3) is between 2.0%and 3.0%.The optimum content of carbon nanotubes is between 0.1%and 0.2%.The optimum content of nano-Al_(2)O_(3) is between 1.0%and 2.0%.The main problems existing in the research and application of nanomaterial-modified geopolymer concrete are summarized,which lays a foundation for the further application of nanomaterial in geopolymer concrete.

关键词： nanomaterials low carbon geopolymer concrete macro-mechanics microstructure

Effect of ivabradine on hyperpolarization activated cation current in canine pulmonary vein sleeve cardiomyocytes with atrial fibrillation

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Journal of Geriatric Cardiology 2008年第1期5卷 39-42页

作者： Yang Li Yan Huang Zongbin Li Hao wang Jianguo Song Yuqi Liu Lei gao Shiwen wang Institute of Geriatric Cardiology Chinese PLA General HospitalBeijing 100853china Institute ofCardiologythe First affilated HospitalXinjiang Medical UniversityUrumqi 830054china Institute of Geriatric CardiologyChinese PLA General HospitalBeijing 100853china Institute of Geriatric CardiologyChinese PLA General HospitalBeijing 100853china Institute ofCardiologythe First affilated HospitalXinjiang Medical UniversityUrumqi 830054china Institute of Geriatric CardiologyChinese PLA General HospitalBeijing 100853china Institute of Geriatric CardiologyChinese PLA General HospitalBeijing 100853china Institute of Geriatric CardiologyChinese PLA General HospitalBeijing 100853china

Objective To study the effect of ivabradine on hyperpolarization activated cation current in canine pulmonary vein(PY) sleeve cardiomyocytes with atrial *** Dissociation of PVs yielded single cardiomyocytes from a Landengorff column without or with pacemaker activity from long-term rapidly atrial pacing (RAP) *** current was measured with the whole-cell patch-clamp *** Compared with the control group,the rapidly atrial pacing canine PV cardiomyocytes had spontaneous diastolic depolarization and had larger If *** (Iva,1 μM),a selective inhibitor of the If current,markedly reduced If currents in the RAP from -2.66±0.4 pA/pF to -1.58±0.1 pA/pF at the test potential of-120 mV (P＜0.01,n=12).Inhibition effect of Iva of If current showed concentration-dependent range from 0.1 to 10.0μM,with IC50 of 2.2 μ M ( 1.8-2.9 μM,95% CL).Furthermore,V1/ of steady-state activated curve was shifted from -84.3±4.9 mV to -106.9±3.4 mV and k value of steady-state activated curve was changed from 12.1+2.6 mV to 9.9±3.4 mV by the application of.1.0 μM Iva ( P＜0.01,n=12).Conclusions Our study revealed that Ivarbadine may significantly decrease If of rapidly atrial pacing pulmonary vein sleeve ceUs with atrial fibdllation.(J Geriatr Cardiol 2008;5:39-42)

关键词： ivarbadine hyperpolarization activated cation anine pulmonary vein sleeves atrial fibrillation

IoT Empowered Early Warning of Transmission Line Galloping Based on Integrated Optical Fiber Sensing and Weather Forecast Time Series Data

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Computers, Materials & Continua 2025年第1期82卷 1171-1192页

作者： Zhe Li Yun Liang Jinyu wang Yang gao State Grid Henan Electric Power Company Electric Power Scientific Research Institute State Grid Henan Electric Power CompanyZhengzhou450052China

Iced transmission line galloping poses a significant threat to the safety and reliability of power systems,leading directly to line tripping,disconnections,and power *** early warning methods of iced transmission line galloping suffer from issues such as reliance on a single data source,neglect of irregular time series,and lack of attention-based closed-loop feedback,resulting in high rates of missed and false *** address these challenges,we propose an Internet of Things(IoT)empowered early warning method of transmission line galloping that integrates time series data from optical fiber sensing and weather ***,the method applies a primary adaptive weighted fusion to the IoT empowered optical fiber real-time sensing data and weather forecast data,followed by a secondary fusion based on a Back Propagation(BP)neural network,and uses the K-medoids algorithm for clustering the fused ***,an adaptive irregular time series perception adjustment module is introduced into the traditional Gated Recurrent Unit(GRU)network,and closed-loop feedback based on attentionmechanism is employed to update network parameters through gradient feedback of the loss function,enabling closed-loop training and time series data prediction of the GRU network ***,considering various types of prediction data and the duration of icing,an iced transmission line galloping risk coefficient is established,and warnings are categorized based on this ***,using an IoT-driven realistic dataset of iced transmission line galloping,the effectiveness of the proposed method is validated through multi-dimensional simulation scenarios.

关键词： Optical fiber sensing multi-source data fusion early warning of galloping time series data IoT adaptive weighted learning irregular time series perception closed-loop attention mechanism

Effects of Magnesium and Ferric Ions on Crystallization of Calcium Sulfate Dihydrate Under the Simulated Conditions of Wet Flue-gas Desulfurization

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Chemical Research in Chinese Universities 2008年第6期24卷 688-693页

作者： gao Xiang HUO wang ZHONG Yi LUO Zhong-yang CEN Ke-fa NI Ming-jiang CHEN Le-ming State Key Laboratory of Clean Energy Utilization Institute of Thermal Energy and Power Engineering Zhejiang University Hangzhou 310027 P. R. China

The influences of magnesium and ferric ions in their different ratios on the rate of gypsum crystallization were studied under the conditions similar to those of wet flue-gas desulfurization（WFGD）. The results show that addition of both Mg^2＋ and Fe^3＋ increased induction time and decreased the growth efficiency up to 50% compared with the baseline（without impurities） depending on the concentration and the type of impurity. The effects of Mg^2＋ and Fe^3＋ on the surface energy and the rate of nucleation were estimated by employing the classical nucleation theory. The surface energy decreased by 8% and 14% with the addition of 0.02 mol/L magnesium or ferric ions, respectively, compared to the baseline. Mg^2＋ and Fe^3＋ made the growth rate of the （020）, （021） and （040） faces of gypsum crystal a much greater reduction, which leads to the formation of needle crystals compared to the baseline which favors the formation of plate or flakes. Furthermore, an edge detection program was developed to quantify the effects of impurities on the filtration rate of gypsum product. The results show that the inhibition efficiency of the presence of 0.02 mol/L Mg^2＋ and Fe^3＋ on the filtration rate of gypsum crystal ranges from 22% to 39%.

关键词： Calcium sulfate dihydrate Morphology Wet flue-gas desulfurization Filtration rate