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Historical simulation and twenty-first century prediction of oceanic CO_2 sink and pH change

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Acta Oceanologica Sinica 2012年第5期31卷 87-97页

作者： BAO ying QIAO Fangli SONG Zhenya College of Physical and Environmental Oceanography Ocean University of ChinaQingdao 266100China First Institute of Oceanography State Oceanic AdministrationQingdao 266061China Key Laboratory of Marine Science and Numerical Modeling State Oceanic AdministrationQingdao 266061China

A global ocean carbon cycle model based on the ocean general circulation model POP and the improved biogeochemical model OCMIP-2 is employed to simulate carbon cycle processes under the historically observed atmospheric CO 2 concentration and different future scenarios （called Rep- resentative Concentration Pathways, or RCPs）. The RCPs in this paper follow the design of Inter- governmental Panel on Climate Change （IPCC） for the Fifth Assessment Report （AR5）. The model results show that the ocean absorbs CO 2 from atmosphere and the absorbability will continue in the 21st century under the four RCPs. The net air-sea CO 2 flux increased during the historical time and reached 1.87 Pg/a （calculated by carbon） in 2005; however, it would reach peak and then decrease in the 21st century. The ocean absorbs CO 2 mainly in the mid latitude, and releases CO 2 in the equator area. However, in the Antarctic Circumpolar Current （ACC） area the ocean would change from source to sink under the rising CO 2 concentration, including RCP4.5, RCP6.0, and RCP8.5. In 2100, the anthropogenic carbon would be transported to the 40 S in the Atlantic Ocean by the North Atlantic Deep Water （NADW）, and also be transported to the north by the Antarctic Bottom Water （AABW） along the Antarctic continent in the Atlantic and Pacific oceans. The ocean pH value is also simulated by the model. The pH decreased by 0.1 after the industrial revolution, and would continue to decrease in the 21st century. For the highest concentration sce- nario of RCP8.5, the global averaged pH would decrease by 0.43 to reach 7.73 due to the absorption of CO 2 from atmosphere.

关键词： ocean carbon cycle model air-sea CO 2 flux anthropogenic carbon pH value

塔里木灌区膜下滴灌棉花水分生产函数及其效益

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干旱地区农业研究 2016年第4期34卷 18-24,54页

作者：闫映宇新疆维吾尔自治区水土保持生态环境监测总站新疆乌鲁木齐830000

以2007—2012年塔里木灌区膜下滴灌田间灌溉试验数据为基础,采用最小二乘法原理,拟合了棉花的水分生产函数模型,分析并计算了棉花最高产量灌溉定额、最佳效益灌溉定额、高效用水灌溉定额,揭示了棉花的水分效应及需水规律。结果表明:塔... 详细信息

以2007—2012年塔里木灌区膜下滴灌田间灌溉试验数据为基础,采用最小二乘法原理,拟合了棉花的水分生产函数模型,分析并计算了棉花最高产量灌溉定额、最佳效益灌溉定额、高效用水灌溉定额,揭示了棉花的水分效应及需水规律。结果表明:塔里木灌区膜下滴灌棉花需水临界期是花铃期和蕾期;产量与耗水量、灌水量均呈良好的二次抛物线关系;合理灌溉定额为3 091~3 464 m^3·hm^(-2),最高产量灌溉定额为3 464 m^3·hm^(-2),高效用水灌溉定额为3 091 m^3·hm^(-2);水资源投入的最佳效益点并非水分利用效率最高点和最高产量点,而是存在于3091~3 464 m^3·hm^(-2)区间;当边际效益等于边际成本时,净收益最大,为24 333.1元·hm^(-2),每立方灌水量净收益7.23元·hm^(-2);现状条件下最佳效益灌溉定额为3 459 m^3·hm^(-2),产量为6 360.7 kg·hm^(-2),与最高产量6 360.8kg·hm^(-2)基本相同,但比最高产量节水5 m^3·hm^(-2),每立方灌水净收益增加0.21元·hm^(-2),水分利用效率提高0.003 kg·m-3。

关键词：膜下滴灌棉花水分生产函数水分利用效率灌水效益

Akt Gene Therapy Enhances Angiogenesis in Ischemic Hind Limb

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Chemical Research in Chinese Universities 2010年第3期26卷 409-414页

作者： HUO Xin ZHANG Qiang LIU ying Department of Geriatrics First Affiliated Hospital China Medical University Shenyang 110001 P. R. China

Both bone marrow-derived mesenchymal stem cells（MSCs） therapy and gene therapy have been applied to animal studies and clinical trials. The goal of this study was to compare the effects of three types of MSCs transplantation. In the first part of the study, MSCs were transduced with the pEGFP-C1 and transfected with the pEGFP-C1/Akt in a model of bilateral hind limb ischemia in rats. Following gene transduction, the production of Akt and VEGF protein was more in the culture media of GFP-Akt/MSCs group than that in those of the GFP/MSCs group In the second part of the study, Sprague-Dawley rats（n=10/group） underwent surgery to create bilateral hind limb ischemia and were randomized into two groups consisting of a GFP/Akt-MSCs group（MSCs suspension, 1×10^7 MSCs/100 μL transfected pEGFP-C1/Akt） and a GFP-MSCs group（MSCs suspension, 1 × 10^7 MSCs/100 μL）. These PEGFP-C1/Akt and PEGFP-C 1 transfected MSCs suspensions were slowly infused into the adductor muscles of the rat＇s left hind limb, while the rat＇s right hind limb in the control group received an equal volume of PBS. Endpoints includes angiographic analysis, evaluation of capillary density, immunohistochemistry for von Willebrand factor （vWF）, immunodetection of Akt and VEGF protein, RT-PCR of VEGF and Akt mRNA levels in vitro and in vivo. Our data indicate that the tissue perfusion can improve capillary density and the mature of vasculature in the GFP-Akt/MSCs group compared to that in the GFP-MSCs group or control group in the rat model of bilateral hind limb ischemia. Transplantation of MSCs transfected with Akt gene may become the future therapy for hind limb ischemia.

关键词： Bone mesenchymal stem cell pEGFP-C1/Akt Hindlimb Ischemia Angiogenesis

Coal mine safety production forewarning based on improved BP neural network

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International Journal of Mining Science and Technology 2015年第2期25卷 319-324页

作者： Wang ying Lu Cuijie Zuo Cuiping School of Management China University of Mining & Technology

Firstly, the early warning index system of coal mine safety production was given from four aspects as per- sonnel, environment, equipment and management. Then, improvement measures which are additional momentum method, adaptive learning rate, particle swarm optimization algorithm, variable weight method and asynchronous learning factor, are used to optimize BP neural network models. Further, the models are applied to a comparative study on coal mine safety warning instance. Results show that the identification precision of MPSO-BP network model is higher than GBP and PSO-BP model, and MPSO- BP model can not only effectively reduce the possibility of the network falling into a local minimum point, but also has fast convergence and high precision, which will provide the scientific basis for the forewarnin~ management of coal mine safetv production.

关键词： Improved PSO algorithm BP neural network Coal mine safety production Early warning

Subcycle electron emission in sequential double ionization by elliptical laser pulses

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Frontiers of physics 2016年第6期11卷 135-142页

作者： Ai-Hong Tong ying-Bin Li Department of Physics and Mechanical Electrical Engineering Hubei University of Education Wuhan 430205 China National Laboratory of Solid State Microstruetures and Department of Physics Nanjing University Nanjing 210093 China

Using a classical ensemble method, we have investigated sequential double ionization (SDI) of Ar atoms driven by elliptical laser pulses. The results show that the ion momentum distribution of the Ar atoms depends strongly on the pulse duration. As the pulse duration increases, the ion momentum distribution changes from two bands to four bands and then to six bands and finally to an eight-band structure. Back analysis of double ionization trajectories shows that the variation of the band structure originates from pulse duration dependent multiple ionization bursts of the second electron. Our calculations indicate that the subcycle electron emission in the SDI could be more easily accessed by using elliptical laser pulses with a longer wavelength. Moreover, we show that there is good correspondence between the scaled radial momentum and the ionization time.

关键词： sequential double ionization pulse duration elliptical laser pulse subcycle electron emission

缝合复合材料弹性性能分析的新方法——流场模型Ⅰ:缝合单层板弹性常数计算

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复合材料学报 2006年第4期23卷 129-135页

作者：刘兵山燕瑛北京航空航天大学飞机设计研究所北京100083

为了求解缝合层合板中单层的弹性常数,基于单层面内纤维走向与绕流流场中流线形状的相似性,建立了与缝合单胞相对应的有限空间定常二维无粘性不可压理想流体的无旋绕流流场模型,流场的几何边界与单胞的边界一致,绕流物面与缝线截面形状... 详细信息

为了求解缝合层合板中单层的弹性常数,基于单层面内纤维走向与绕流流场中流线形状的相似性,建立了与缝合单胞相对应的有限空间定常二维无粘性不可压理想流体的无旋绕流流场模型,流场的几何边界与单胞的边界一致,绕流物面与缝线截面形状一致。用该流场的速度变化描述单胞面内纤维体积含量的变化,用流线形状描述缝线周围面内纤维的变形。以流场模型为基础,用细观力学方法和均匀化方法求得缝合单层的弹性常数,结果与实验值吻合。最后用流场模型分析了缝合参数对缝合单层弹性常数的影响。

关键词：流场模型缝合单层弹性常数

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Investigating the disk-corona relation in a blue AGN sample

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Research in Astronomy and Astrophysics 2009年第9期9卷 966-978页

作者： Jie-ying Liu Bi-Fang Liu National Astronomical Observatories / Yunnan Observatory Chinese Academy of SciencesKunming 650011 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

We compile a blue AGN sample from SDSS and investigate how the ratio of hard X-ray to bolometric luminosity depends on the Eddington ratio and black hole mass. Our sample comprises 240 radio-quiet Seyfert 1 galaxies and QSOs. We find that the fraction of hard X-ray luminosity （log（L2-10keV/L bol）） decreases with an increase of the Eddington ratio. We also find that the fraction of hard X-ray luminosity is independent of the black hole mass for radio-quiet AGNs. The relation of log（L2-10 keV/Lbol） decreasing with increasing Eddington ratio indicates that X-ray bolometric correction is not a constant, from a larger sample supporting the results of Vasudevan ＆ Fabian. We interpret our results by the disk corona evaporation/condensation model. In the frame work of this model, Compton cooling becomes efficient in cooling the corona at high accretion rates （in units of Eddington rate）, leading to condensation of coronal gas to the disk. Consequently, the relative strength of the corona to the disk becomes weaker at higher Eddington ratios. Therefore, the fraction of hard X-ray emission to disk emission and hence to the bolometric emission is smaller at higher Eddington ratios. The independence of the fraction of hard X-ray luminosity with respect to the mass of the black hole can also be explained by the disk corona model since the coronal structure and luminosity （in units of Eddington luminosity） are independent of the mass of black holes.

关键词： accretion: accretion disks -- galaxies: active -- X-rays: galaxies

On the Fourth Power Mean of the Character Sums Over Short Intervals

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Acta Mathematica Sinica,English Series 2007年第1期23卷 153-164页

作者： Wen Peng ZHANG Xiao ying WANG Research Center for Basic Science Xi'an Jiaotong University Xi'an 710049 P. R. China

The main purpose of this paper is to study the mean value properties of the character sums over the interval [1,p/8） by using the mean value theorems of the Dirichlet L-functions, and give an interesting mean value f... 详细信息

关键词： character sums short intervals fourth power mean asymptotic formula

Dynamics and collisions of episodic jets from black holes and accretion disk systems

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Research in Astronomy and Astrophysics 2015年第2期15卷 207-214页

作者： ying Meng Jun Lin Feng Yuan Yunnan Observatories Chinese Academy of Sciences University of Chinese Academy of Sciences Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical ObservatoryChinese Academy of Sciences

In many astrophysical black hole systems, episodic jets of plasma blobs have been observed, which are much faster and more powerful than continuous jets. A magnetohydrodynamical model was proposed by Yuan et al. to study the formation of episodic jets in Sgr A＊. By taking Sgr A＊ and a stellar mass black hole as examples, we modify the model of Yuan et al. by including the effects of relativity, and further study the relativistic motion and expansion of episodic jets of plasma blobs. Then we study the collision between two consecutive ejections in the modified model, and calculate the magnetic energy released in the collision. Our results show two consecutive blobs can collide with each other, and the released magnetic energy is more than 1050 erg, which supports the idea that a gamma-ray burst is powered by the collision of episodic jets, as suggested by Yuan ＆ Zhang.

关键词： accretion, accretion disks black hole physics magnetohydrodynamics (MHD) ISM: jets and outflows gamma-ray bursts: general