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The impact of the environmental factors on the photosynthetic activity of common pine (Pinus sylvestris) in spring and in autumn in the region of Eastern Siberia

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Journal of Forestry Research 2018年第6期29卷 1465-1473页

作者： n.E.Korotaeva M.V.Ivanova g.g.Suvorova g.B.Borovskii Siberian Institute of Plant Physiology and Biochemistry Siberian Branch of Russian Academy of Sciences

The taiga coniferous forests of the Siberian region are the main carbon sinks in the forest ***, the size of the carbon accumulation is determined by the photosynthetic productivity, which is strongly influenced by environmental factors. As a result,an assessment of the relationship between environmental factors and photosynthetic productivity makes it possible to calculate and even predict carbon sinks in coniferous forests at the regional level. However, at various stages of the vegetative period, the force of the connection between environmental conditions and the productivity of photosynthesis may change. In this research, correlations between the photosynthetic activity of Scots pine(Pinus sylvestris L.) with the environmental conditions were compared in spring and in autumn. In spring, close positive correlation of the maximum daily net photosynthesis was identified with only one environmental factor. For different years, correlations were for soil temperature(rs= 0.655,p = 0.00315) or available soil water supply(rs= 0.892,p = 0.0068). In autumn within different years, significant correlation was shown with two(temperature of air and soil; rs= 0.789 and 0.896, p = 0.00045 and 0.000006,respectively) and four factors: temperature of air(rs=0.749, p = 0.00129) and soil(rs= 0.84, p = 0.00000),available soil water supply(rs= 0.846, p = 0.00013) and irradiance(rs= 0.826, p = 0.000001). Photosynthetic activity has a weaker connection with changes in environmental factors in the spring, as compared to *** is explained by the multidirectional influence of environmental conditions on photosynthesis in this period and by the necessity of earlier photosynthesis onset, despite the unfavorable conditions. This data may be useful for predicting the flow of carbon in dependence on environmental factors in this region in spring and in autumn.

关键词： Pinus sylvestris L. Eastern Siberia Correlations Photosynthetic productivity Seasonal changes in environment

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Unified Treatment of Screening Coulomb and Anharmonic Oscillator Potentials in Arbitrary Dimensions

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Communications in Theoretical Physics 2006年第5期45卷 807-812页

作者： Blent gnl Okan zer Mehmet Kocak Department of Engineering Physics Faculty of Engineering University of Gaziantep 27310 Gaziantep Trkiye

A mapping is obtained relating radial screened Coulomb systems with low screening parameters to radial anharmonic oscillators in n-dimensional space. Using the formalism of supersymmetric quantum mechanics, it is show... 详细信息

关键词： supersymmetric quantum mechanics screening Coulomb n-dimensional space

Optimal Placement and Sizing of Distributed generation Using Metaheuristic Algorithm

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Computer Systems Science & Engineering 2022年第5期41卷 493-509页

作者： D.nageswari n.Kalaiarasi g.geethamahalakshmi Department of Electrical and Electronics Engineering RMK College of Engineering and Technology(RMKCET)Thiruvallur601206India Department of Electrical and Electronics Engineering RMK Engineering CollegeGummidipoondi601206India

Power loss and voltage uncertainty are the major issues prevalently faced in the design of distribution *** such issues can be resolved through effective usage of networking reconfiguration that has a combination of Distributed generation(Dg)units from distribution *** this point of view,optimal placement and sizing of Dgs are effective ways to boost the performance of power *** optimum allocation of Dgs resolves various problems namely,power loss,voltage profile improvement,enhanced reliability,system stability,and *** research works have been conducted to address the distribution system problems in terms of power loss,energy loss,voltage profile,and voltage stability depending upon optimal Dg *** this motivation,the current study designs a Chaotic Artificial Flora Optimization based on Optimal Placement and Sizing of Dgs(CAFO-OPSDg)to enhance the voltage profiles and mitigate the power ***,the CAFO algorithm is derived from the incorporation of chaos theory concept into conventional artificial flora optimization AFO algorithm with an aim to enhance the global optimization *** fitness function of CAFO-OPSDg algorithm involves voltage regulation,power loss minimization,and penalty *** consider the actual power system scenario,the penalty factor acts as an important element not only to minimize the total power loss but to increase the voltage profiles as *** experimental validation of the CAFO-OPSDg algorithm was conducted against IEEE 33 Bus system and IEEE 69 Bus *** outcomes were examined under various test *** results of the experiment established that the presented CAFO-OPSDg model is effective in terms of reducing the power loss and voltage deviation and boost-up the voltage profile for the specified system.

关键词： Voltage profile enhancement loss minimization distributed generation optimal dg sizing optimal Dg placement metaheuristics

Experimental study on microstructural and corrosion behaviors of friction stir processed steel with CoCrFeCuTi HEA reinforcement and effect of annealing

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Science China Technological Sciences 2025年第1期 233-250页

作者： S.Aravind KRISHnA n.RADHIKA Alokesh PRAMAnIK n.JEYAPRAKASH Department of Mechanical Engineering Amrita School of EngineeringAmrita Vishwa Vidyapeetham School of Civil and Mechanical Engineering Curtin University School of Mechanical and Electrical Engineering China University of Mining and Technology

The ability to perform against extreme corrosion environments in stainless steel depreciates under challenging conditions in industrial applications. This can be resolved by employing surface modification techniques to modify the surface with the required characteristics. The present study investigates the outcomes of friction stir processing of SS304 with CoCrFeCuTi high entropy alloy(HEA) as reinforcement and the property enhancements post-annealing. The synthesized CoCrFeCuTi HEA exhibited irregular fragments with 17 μm mean particle size and body centred cubic(BCC) phase. The microstructure of the processed surface revealed ultra-refined grains with a uniform distribution of HEA filler. The microstructures of the samples annealed at 400℃, 550℃, 700℃ and 850℃ for 2 h also showed significant grain growth and grain refinements. The processed sample with HEA reinforcement annealed at 700℃ exhibited enhanced microhardness and tensile strength by 63% and 0.88 times than that of the processed sample with HEA pre-annealing. The subsequent electrochemical corrosion test displayed better corrosion resistance for the HEA-processed and annealed sample. Hot corrosion tests at 900℃ showcased excellent resistance for the HEA processed and annealed samples by 14.92%, 12.75%, and 14.83% against the samples pre-annealed under three different salt mixtures, and the corroded surface was analyzed.

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低渗油藏注气提高采收率技术筛选——以辽河油田齐131块为例

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低渗油藏注气提高采收率技术筛选——以辽河油田齐131块为例

作者： Ezekiel,Justin chima 中国石油大学(华东)

学位级别：硕士

辽河油田Q131区块属于低渗水敏轻质油藏,原始地层压力33.4 MPa,油藏温度98-112℃,地质储量(OOIP)253万m3,地层原油粘度0.5 mPa.s。其特征是油层较厚、地层倾角较大,但地层能量不足,初期压力衰竭开采产量较低。由于渗透率低及水敏严重,... 详细信息

辽河油田Q131区块属于低渗水敏轻质油藏,原始地层压力33.4 MPa,油藏温度98-112℃,地质储量(OOIP)253万m3,地层原油粘度0.5 mPa.s。其特征是油层较厚、地层倾角较大,但地层能量不足,初期压力衰竭开采产量较低。由于渗透率低及水敏严重,后期水驱也未收到成效,目前注水困难,注不进采不出”的矛盾突出。因此,该区块正在考虑实施注气提高采收率技术。注气已经成为一种有效的提高采收率方法,其原理主要在于增加或保持地层压力,提高驱油和波及效率,从而提高原油采收率。根据气源情况,有三种注气技术可以应用于Q131区块:注空气、注CO以及注n。本研究针对Q131工况,考虑了注气高效重力稳定驱替方式在Q131应用的优势,在不同注气技术在目标区块提高采收率机理分析的基础上,对三种技术的技术和经济可行性进行了分析。论文对目标区块的生产历史和及实时数据进行了总结分析,并评估了在本区块进行注气提高采收率的可行性。结合理论分析、注气提高采收率机理、现场经验、室内试验研究、PVT分析和油田生产数据历史拟合,运用CMg-STARS数值模拟软件,建立三种注气技术应用的油藏数值模拟模型。然后根据注入不同气体对保持地层压力、提高采收率、经济性、安全性等的影响进行筛选。对于注空气工艺,在实验基础上建立低温氧化动力学模型并应用于油藏模拟中。注空气低渗岩心驱替实验表明注空气可以得到比水驱更高的采收率,并且其采收率随着地层倾角的增加而增加。温度在130-170°C的轻质油低温氧化实验表明,油层内的产生的自发低温氧化反应能完全消耗O并且CO转换率高达58%。油藏数值模拟结果表明,受注入井位置和数量限制,气体注入速率及注气量是影响原油产量的重要因素。累积产油量随着气体注入速度和注入量增加而增加,并有注入量的最优值。注空气过程中,在模拟的注入量下生产井未没有出现O突破的现象。以单井30000m3/day的速度向地层中注入空气、CO和n(4口注入井)30年,原油采收率分别可达到35%,36.5%,35.5%,其中注入CO的开采效果最好。气体早期突破及油井产出气油比太高是注气工艺的重要问题,关闭的高气油比井是降低气体产出的有效手段。敏感性分析表明,在维持相同注入量下,但采用关闭高气油比油井的方法降低气体产出量,其20年的注入空气、CO和n的原油采收率可分别达到33.5%,36%,and 34%,使得注气项目具有更高的经济性。初期的经济性和安全性分析也证明三种注气技术都具有可行性和经济性。其中,由于操作成本低,注空气成为三种方法中最具前景的方法。此外,详细讨论了不同注气技术安全性和防腐问题,也对低渗油藏更有效开发提出了建议。

关键词：注空气注CO2 注n2 低渗油藏提高采收率空气驱低温氧化实验数值模拟经济安全性评价

Pitting and stress corrosion cracking studies on AISI type 316n stainless steel weldments

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Defence Technology（防务技术） 2018年第3期14卷 226-237页

作者： Anita Toppo M.g.Pujar n.Sreevidya John Philip Corrosion Science and Technology Division Indira Gandhi Centre for Atomic Research Materials Development and Technology Division Indira Gandhi Centre for Atomic Research

Pitting and stress corrosion cracking(SCC) studies on the 316 n stainless steel(SS) weldments in aswelded(AW) and thermally aged(solution annealing(SA), 550C/4 h and 750C/1 h) conditions were carried out in acidic and acidic chloride media. Pitting corrosion and SCC resistance was the highest for SA weldment, which was attributed to homogenization of microstructural and microchemical heterogeneities during solution annealing. SA specimen showed the most stable passive film as compared to AW weldment because of higher amount of delta-ferrite in AW weld metal, which resulted in an increased heterogeneity and inferior SCC resistance in AW. Stability of passive film was found to be adversely affected due to heat treatments(at 550C/4 h and 750C/1 h) because of the precipitation of carbide and sigma phases.

关键词：压力腐蚀不锈钢 AISI 焊接金属 SCC 稳定性氯化物微结构

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numerical Simulation of Coupled nonlinear Schrodinger Equations Using the generalized Differential Quadrature Method

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Chinese Physics Letters 2011年第2期28卷 5-8页

作者： R.Mokhtari A.Samadi Toodar n.g.Chegini Department of Mathematical Sciences Isfahan University of TechnologyIsfahan 84156-83111Iran Department of Mathematics Tafresh UniversityTafresh 39518-79611Iran

We the extend application of the generalized differential quadrature method(gDQM)to solve some coupled nonlinear Schr(o)dinger *** cosine-based gDQM is employed and the obtained system of ordinary differential equations is solved via the fourth order Runge-Kutta *** numerical solutions coincide with the exact solutions in desired machine precision and invariant quantities are conserved *** comparisons with the methods applied in the literature are carried out.

关键词： method invariant ordinary

Lipid enhancement in microalgae by temporal phase separation:Use of indigenous sources of nutrients

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Chinese Journal of Chemical Engineering 2018年第1期26卷 175-182页

作者： nidhin Sreekumar Ajit Haridas g.S.godwin n.Selvaraju national Institute of Technology(nITC) CalicutIndia national Institute for Interdisciplinary Science and Technology(nIIST) Council of Scientific&Industrial Research(CSIR)ThiruvananthapuramIndia

Microalgae have been recommended as superior candidate for fuel production because of their advantages of higher photosynthetic efficiency, biomass & lipid productivity, and faster growth rate as compared to other energy crops. To meet up all these criteria, we have developed a continuous outdoor micro-algal raceway pond reactor(RPR) and a lab scale indoor tubular photo bioreactor(PBR) for biofuel production. An attempt to utilise indigenous sources of nutrients to improve the economics also revealed that micro-algal culturing can also be used as a mode of nutrient removal and water treatment. The photosynthetic rate and lipid production were enhanced by arresting daytime cell division and promoting night-time cell division. A 50% lipid improvement was observed for the particular algal consortia. Microscopic studies revealed that temporal phase separation could be achieved by adjusting nutrient distribution pattern. To monitor temporal phase separation, it is required to know DnA multiplication model. Quantification of g DnA in RPR confirmed that cell division happens during the night which positively affects the photosynthetic efficiency and lipid productivity of microalgae.

关键词： Temporal phase separation Lipid enhancement Microalgae Biodiesel

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Thermogravimetric kinetic analysis of nannochloropsis oculata combustion in air atmosphere

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Frontiers in Energy 2015年第2期9卷 125-133页

作者： SUKARnI SUDJITO nurkholis HAMIDI I.n.g. WARDAnA Uun YAnUHAR Department of Mechanical Engineering Faculty of Engineering StateUniversity of Malang J1. Semarang 5 Malang 65145 East-JavaIndonesia Department of Mechanical Engineering Faculty of EngineeringUniversity of Brawijaya J1. Mayjen Haryono 167 Malang 65145East-Java Indonesia Biotechnology Laboratory Department of Water Resources Manage-ment Faculty of Fisheries and Marine Sciences University ofBrawijaya J1. Veteran Malang 65145 East-Java Indonesia

The thermal behavior of nannochloropsis oculata combustion in air atmosphere were investigated by performing experiments on STA PT1600 Thermal Analyzer at heating rates of 10℃/min, 40℃/min and 70℃/min and range of temperatures from room tempera- ture to 1200℃. The kinetic parameters were evaluated by using Kissinger and Ozawa methods. The result showed that nannochloropsis oculata combustion occurred in five stages. Started with initial devolatilization, the main thermal decomposition and combustion process, transition stage, the combustion of char and the last stage was the slow burning reaction of residual char. In line with increasing heating rate, the mass loss rate increased as well, but it delayed the thermal decomposition processes toward higher temperatures. The average activation energy at the main thermal decomposition stage and the stage of char combustion were approximately 251 kJ/mol and 178 kJ/mol, respectively.

关键词： nannochloropsis oculata combustion,kinetic parameters air atmosphere thermogravimetric