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Production sharing contract: An analysis based on an oil price stochastic process

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Petroleum Science 2012年第3期9卷 408-415页

作者： Liu Mingming Wang zhen zhao Lin Pan Yanni xiao Fei School of Business Administration China University of PetroleumBeijing 102249 China China National Oil&Gas Exploration and Development Corporation Beijing 100083China

Assuming that oil price follows the stochastic processes of Geometric Brownian Motion （GBM） or the Mean-Reverting Process （MRP）, this paper takes the net present value （NPV） as an economic index and models the PSC in 11 different scenarios by changing the value of each contract element （i.e. royalty, cost oil, profit oil as well as income tax）. Then the NPVs are shown in probability density graphs to investigate the effect of different elements on contract economics. The results show that under oil price uncertainty the influence of profit oil and income tax on NPV are more significant than those of royalty and cost oil, while a tax holiday could improve the contractor＇s financial status remarkably. Results also show that MRP is more appropriate for cases with low future oil price volatility, and GBM is best for high future oil price volatility.

关键词： Production sharing Geometric Brownian motion Mean-Reverting Process oil contract international petroleum cooperation

A NEW METHOD FOR NUMERICAL SIMULATION OF TWO TRAINS PASSING BY EACH OTHER AT THE SAME SPEED

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Journal of Hydrodynamics 2010年第5期22卷 697-702页

作者： zhao xiao-li SUN zhen-xu School of Aerospace Tsinghua University Beijing China State Key Laboratory for Turbulence and Complex Systems College of Engineering Peking University Beijing China

A new method is proposed to numerically simulate problems of trains passing by each other at the same speed, and is implemented in UDF language of commercial software Fluent. Because only a half of the computational domain is required and the dynamic mesh technique is avoided, the computational efficiency is greatly improved. A two-dimensional test case is used for validation, which shows that the flow field and the pressure wave during the train-passing events can be correctly calculated by this new method. This method can be easily extended to three-dimensional simulations, to deal with practical problems.

关键词： trains passing by each other rotational symmetry dynamic mesh pressure wave

Gravitational Corrections to Energy-Levels of a Hydrogen Atom

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Communications in Theoretical Physics 2007年第4期47卷 658-662页

作者： zhao zhen-Hua LIU Yu-xiao LI Xi-Guo Institute of Modern Physics the Chinese Academy of Sciences Lanzhou 730000 China Institute of Theoretical Physics Lanzhou University Lanzhou 730000 China

The first-order perturbations of the energy levels of a hydrogen atom in central internal gravitational field are investigated. The internal gravitational field is produced by the mass of the atomic nucleus. The energy shifts are calculated for the relativistic 1S, 2S, 2P, 3S, 3P, 3D, 4S, and 4P levels with Schwarzschild metric. The calculated results show that the gravitational corrections are sensitive to the total angular momentum quantum number.

关键词： hydrogen atom gravitational perturbation generally covariant Dirac equation

Discrete-frequency Convergence of Iterative Learning Control for Linear Time-invariant systems with Higher-order Relative Degree

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International Journal of Automation and computing 2015年第3期12卷 281-288页

作者： xiao-E Ruan zhao-zhen Li Z.Z.Bien School of Mathematics and Statistics Xi an Jiaotong University Department of Electrical Engineering Korea Advanced Institute of Science and Technology

In this paper, a discrete-frequency technique is developed for analyzing sufficiency and necessity of monotone convergence of a proportional higher-order-derivative iterative learning control scheme for a class of linear time-invariant systems with higher-order relative degree. The technique composes of two steps. The first step is to expand the iterative control signals, its driven outputs and the relevant signals as complex-form Fourier series and then to deduce the properties of the Fourier coefficients. The second step is to analyze the sufficiency and necessity of monotone convergence of the proposed proportional higher-order-derivative iterative learning control scheme by assessing the tracking errors in the forms of Paserval s energy modes. Numerical simulations are illustrated to exhibit the validity and the effectiveness.

关键词： Iterative learning control monotone convergence discrete frequency-domain spectrum Fourier series Parseval s energy equality rel

Berbamine inhibits proliferation and induces apoptosis of KU812 cells by increasing Smad3 activity

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第7期12卷 568-574页

作者： Yun LIANG Xi QIU Rong-zhen XU xiao-ying zhao Department of Hematology the Second Affiliated Hospital School of Medicine Zhejiang University Hangzhou 3 10009 China Cancer Institute School of Medicine Zhejiang University Hangzhou 310009 China

Objective: The cytotoxic effect of berbamine on chronic myeloid leukemia (CML) cell line KU812 was evaluated,and the mechanisms of its action were ***: The effect of berbamine on the KU812 cell growth was determined by methyl thiazolyl tetrazolium (MTT) *** cytometry was used to profile cell cycle alteration upon berbamine *** transcription polymerase chain reaction (RT-PCR) was carried out to determine the transcripts of transforming growth factor-β (TGF-β) receptors (TβRs),Smad3,c-Myc,cyclin D1,p21Cip1(p21),and p27Kip1(p27).Changes in the protein levels of total Smad3,phosphorylated Smad3,the downstream targets of Smad3,and specific apoptosis-related factors were evaluated by Western ***: Berbamine inhibited KU812 cell proliferation in a doseand time-dependent manner,and the half maximal inhibitory concentration (IC50) values for treatments of 24,48,and 72 h were 5.83,3.43,and 0.75 μg/ml,*** induced G1 arrest as well as apoptosis in KU812 *** of Smad3 and p21 were up-regulated,while those of TβRI,TβRII,c-Myc,cyclin D1 and p27 were not changed *** protein levels of both total Smad3 and phosphorylated Smad3 were both up-regulated after berbamine treatment,together with decreased c-Myc and cyclin D1 and increased ***,the levels of the anti-apoptotic proteins,such as Bcl-2 and Bcl-xL,were decreased,whereas pro-apoptotic Bax was ***: Berbamine suppresses KU812 cell proliferation through induction of cell cycle arrest in G1 and *** activates Smad3 without additional stimulation of TGF-β,and alters the levels of the Smad3 downstream targets,including c-Myc,cyclin D1 and *** findings suggest that berbamine is a promising drug in the treatment of advanced stage patients with CML.

关键词： Berbamine Apoptosis Smad3 KU812 cells

One-step synthesis of cyclic polypyrazole and the self-assembly vesicles driven by hydrogen bond

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Chinese Chemical Letters 2022年第2期33卷 825-829页

作者： zhen Lu Bogeng Guo Yulai zhao Linxi Hou Longqiang xiao Department of Materials-Oriented Chemical Engineering College of Chemical EngineeringFuzhou UniversityFuzhou 350116China Fujian Key Laboratory of Advanced Manufacturing Technology of Specialty Chemicals Fuzhou UniversityFuzhou 350116China

The synthesis of cyclic polymer is an important topic in polymer chemistry. Herein, we report a one-step method to prepare cyclic polypyrazoles. Monomers with two functional groups, diazo and alkyne, were synthesized and polymerized via 1,3-diploar cycloaddition in bulk under heating without any *** with molecular weights in the range of 3800-4400 g/mol and yields in the range of 78.8-98.7% were successfully synthesized. No chain end group was detected by LC-QTOF-MS and FTIR, which proves the cyclic structure of polypyrazoles. What is noteworthy is that the cyclic polypyrazoles can selfassemble into vesicles during the reprecipitation process, which was proved by the results of SEM and TEM. The reason for that is the formation of intermolecular hydrogen bond between NH and ester groups.

关键词： 1,3-Dipolar cycloaddition Polypyrazole Self-assembly Cyclic polymers

日本新糠虾卵巢和肝胰腺主要细胞内5-HT的免疫组织化学定位

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水产学报 2011年第2期35卷 208-213页

作者：杨丽丽杨筱珍赵柳兰成永旭吴旭干上海海洋大学省部共建水产种质资源发掘与利用教育部重点实验室上海市高校水产养殖学E-研究院

运用免疫组化方法,观察了5-HT阳性物质在日本新糠虾不同发育期的卵巢卵细胞和滤泡细胞及肝胰腺细胞中的分布和变化。结果表明:随卵细胞的发育,滤泡细胞逐渐迁移至其近旁。各期卵巢卵细胞和滤泡细胞及肝胰腺细胞中均存在大量5-HT阳性细胞... 详细信息

运用免疫组化方法,观察了5-HT阳性物质在日本新糠虾不同发育期的卵巢卵细胞和滤泡细胞及肝胰腺细胞中的分布和变化。结果表明:随卵细胞的发育,滤泡细胞逐渐迁移至其近旁。各期卵巢卵细胞和滤泡细胞及肝胰腺细胞中均存在大量5-HT阳性细胞,阳性物质呈深棕色;各期卵巢中5-HT在滤泡细胞内均呈阳性;在Ⅰ、Ⅱ和Ⅲ期卵巢中卵细胞胞质和胞核均呈阳性,且阳性强度呈递减;Ⅳ期卵巢中5-HT在卵细胞中呈阴性,而在Ⅴ期卵巢中5-HT在卵细胞中又呈现弱阳性。5-HT在发育各期的肝胰腺细胞中均呈阳性。同一期卵巢中,不同类型肝胰腺细胞间5-HT的分布没有差别。除Ⅳ期卵巢外,在其余各期卵巢中5-HT阳性强度在卵细胞胞质和肝胰腺细胞胞质中表现一致。

关键词：日本新糠虾 5-HT 卵细胞滤细胞肝胰腺细胞

Dynamic changes of aquaporin-4 on hippocmpal astrocytes after ligated bilateral common carotid arteries in rats

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Dynamic changes of aquaporin-4 on hippocmpal astrocytes afte...

Influence of phosphorus on Microcystis growth and the changes of other environmental factors

中国神经科学学会第九届全国学术会议暨第五次会员代表大会

作者： xiao-zhen zhao~(1,2,*),Ren LIN~1,Hao CHEN~3,Rong-Hui QIU~1,Ling LIN~2,Wei WANG~(1,2) 1 Deparment of Anatomy,Histology and Embryology,Fujian Medical University,Fuzhou 350004,China 2 Centre of Neuroscience,Fujian Medical University,Fuzhou 350004,China 3 Department of Ultrasonic,Changle City Hospital,Changle 350200,China

＜正＞Objective Water balance between cells and extracellular compartments is essential for proper functioning of the central nervous system.A growing body of evidence suggests that water channel aquaporin-4（AQP4） is a potential molecular target for the regulation astrocytes *** present study aimed to investigate the expression of aquaporin-4 in astrocytes and its relationship to memory impairment after ligated bilateral common carotid arteries in *** One hundreds and eight Healthy Sprague-Dawley rats（Weighing 200-250 g） randomly divided into the control group and the experiment *** then the rats were subdivided into 9 groups（6 rats for each） at an interval of 3 h,6 h,24 h,2 d,3 d,1 w,2 w,1 m and 2 m *** and double immunofluorescence techniques,confocal laser scanning microscopy and morphologic parameters measurement were used to assess AQP4 protein *** The AQP4 selectively expressed in the cell membrane of astrocytes and its foot processes adjacent to endothelial *** mean fluorescence intensity of AQP4 in the experiment group significantly increased after 6 h and had its peak at 2 *** return to normal after 1 week,and decrease after 1 *** number of coexist AQP4 and GFAP is decreased after 1 *** This study indicates that AQP4 in astrocytes may play a role in the formation of memory impairment after ligated bilateral common carotid arteries in rats.

关键词： aquaporin-4 astrocyte ischemia memory impairment

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Journal of Environmental Sciences 2005年第6期17卷 937-941页

作者： JIN Xiang-can CHU zhao-sheng YI Wen-li HU xiao-zhen Research Center for Lake Ecology and Environments Chinese Research Academy of Environmental Sciences Beijing 100012 China Department of Resources and Environments Northwest Sci-Tech University of Agriculture and Forestry Shanxi 712100China

The growth processes of Microcystis aeruginosa （FACHB-41） in simulated Taihu Lake water with different phosphorus concentrations were investigated using laboratory microcosms. The algal biomass increased with the increase of phosphorus concentration when it was lower than 0.445 mg/L, while the dissolved oxygen （DO） and pH increased, dissolved inorganic nitrogen （DIN） and light intensity underwater（I） decreased. Responding to the changes of the “environmental factors”, the cellular carbohydrate and its ratio to cellular protein decreased generally as phosphorus increased. However, when phosphorus concentration was higher than l. 645 mg/L, the biomass, the “environmental factors”, the cellular carbohydrate and its ratio to cellular protein did not change likewise. Since the environmental factors and the physiological and biochemical responses are important factors, the change of environmental factors and cell physiology and biochemistry induced by phosphorus may become the key factors that steer the growth and dominance of Microcystis under certain conditions. To sum up, phosphorus not only stimulate the growth of Microcystis directly by supplying nutrient element, but also has complex interactions with other “environmental factors” and play important roles in the growth processes of Microcystis .

关键词： Microcystis aeruginosa microcosm phosphorus