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β葡萄糖分子开环的计算研究:卤素轰击（英文）

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计算机与应用化学 2015年第6期32卷 646-650页

作者：许军伟刘云霄 tony.c.scott 冯琳马宁杨平张文星太原理工大学物理与光电工程学院

生物质能源的主要来源纤维素,在工业上极易水解得到β葡萄糖。β葡萄糖是环状分子,很稳定,难以利用。卤素离子是低温等离子体技术中广泛使用的离子源,同时也是电负性很强且易与有机分子结合导致开环的元素。基于第一性原理分子动力学,... 详细信息

生物质能源的主要来源纤维素,在工业上极易水解得到β葡萄糖。β葡萄糖是环状分子,很稳定,难以利用。卤素离子是低温等离子体技术中广泛使用的离子源,同时也是电负性很强且易与有机分子结合导致开环的元素。基于第一性原理分子动力学,我们采用卤素轰击β葡萄糖分子,导致开环形成链醇。在研究了各种初始反应构型后,我们发现开环过程中β葡萄糖和卤素之间发生了明显的电荷转移。结合电荷布局分析卤素的阴离子效应和水溶液效应发现β葡萄糖和卤素之间的电荷转移是开环反应发生的主要原因,而且电荷转移依赖于反应的条件。通过比较不同反应条件下的反应速率、产物寿命、所需能量以及产物燃烧热,我们发现溴离子在氧原子上方轰击β葡萄糖的成本最低,最利于实际的应用。对反应产物进一步加氢脱氧,将会得到液态的烷烃燃料。

关键词： β葡萄糖轰击卤素分子动力学

Fundamental Analysis of Helium-Gas coolant Leakage Rate Through First-Wall cracks in Tokamak Fusion Reactors

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Journal of Thermal Science 1993年第1期2卷 12-17页

作者： tony c.Min Department of Mechanical Engineering North Carolina A & TState UniversityGreensboroNC 27411 U.S.A.

A fundamental analysis of helium-gas coolant leakage rate through first-wall cracks in Tokamak fusion reactors was made. criteria for ascertaining the correct flow models were thoroughly investigated. After testing the criteria, it was determined that the correct model is the compressible choked flow for the helium-gas coolant under the normal operating conditions in the Tokamak fusion reactors. The upper bound leakage rates through metallic wall for two crack sizes were calculated. The calculated maximum numbers of allowable cracks through metallic and silicon-carbon composite wall were also reported. The experimental data of specimen S-23 (the small crack size), checked with the predicted or calculated leakage rate. But the experimental data of specimen S-4 (the large crack size, which is only 4.4 times larger than the crack size of specimen S-23) were two orders of magnitude higher than the calculated value. This is probably due to the many through-cracks undetected and therefore, not reported in the experiment, and not due to the difference in crack sizes. It should be noted that since there are only two test data points, it is recommended that more testing or experimental data will be needed. The results of two previous investigations about the calculated leakage values, their equations used, and their flow models employed were also reviewed. It is concluded that the correct model for the analysis is the compressible choked flow, and that helium can be as an effective coolant for fusion power reactors. Several recommendations are also made. Specifically, more experiments for helium, and similar analysis and experiments for lithium and water coolant are needed; and should be encouraged.

关键词： coolant leakage rate Tokamak fusion reactor flow model.

Numerical Study on the Influence Mechanism of Inlet Distortion on the Stall Margin in a Transonic Axial Rotor

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Journal of Thermal Science 2012年第3期21卷 209-214页

作者： scott c.Morris Hessert Laboratory Department of Mechanical and Aerospace EngineeringUniversity of Notre Dame

A numerical study is conducted to investigate the influence of inlet flow condition on tip leakage flow (TLF) and stall margin in a transonic axial rotor.A commercial software package FLUENT,is used in the *** rotor investigated in this paper is ND_TAc rotor,which is the rotor of one-stage transonic compressor in the University of Notre *** varied inlet flow conditions are *** inlet boundary condition with hub distortion provides higher axial velocity for the incoming flow near tip region than that for the clean inflow,while the incoming main flow possesses lower axial velocity near the tip region at tip distortion inlet boundary *** the total pressure ratio curves for the three inlet flow conditions,it is found that the hub dis-torted inlet boundary condition improves the stall margin,while the tip distorted inlet boundary condition dete-riorates compressor *** axial location of interface between tip leakage flow (TLF) and incoming main flow (MF) in the tip gap and the axial momentum ratio of TLF to MF are further *** is demonstrated that the axial momentum balance is the mechanism for interface *** hub distorted inflow could de-crease the axial momentum ratio,suppress the movement of the interface between TLF and MF towards blade leading edge plane and thus enhance compressor stability.

关键词： Inlet distortion tip leakage flow stall margin axial momentum balance

Unveiling the shadows: a qualitative exploration of barriers to rooftop solar photovoltaic adoption in residential sectors

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clean Energy 2024年第5期8卷 218-228页

作者： tony c.Mathew Sridevi Nagaraja Pandian School of commerce Kumaraguru College of Liberal Arts and ScienceCoimbatore 641035Tamil NaduIndia

In the face of global climate change,the urgent shift towards renewable energy sources such as solar power is vital for reducing greenhouse gas emissions and fostering a sustainable future,presenting a universal challenge and opportunity for energy policy ***’s adoption of rooftop solar photovoltaic is pivotal due to its vast solar potential,which aligns with national goals to increase renewable energy capacity,reduce carbon emissions,and achieve energy ***’s geographical location offers abundant solar potential,making it a prime candidate for the adoption of rooftop solar photovoltaic *** with the state’s strong commitment to renewable energy initiatives such as the ambitious“SOURA”(solar subsidy program by the Kerala State Electricity Board)project and various incentives for solar adoption,Kerala stands at the forefront of India’s transition towards sustainable energy *** the barriers to rooftop solar photovoltaic adoption in Kerala is crucial for tailoring ef-fective policies and strategies that address specific hindrances from economic constraints to informational *** study employs a qualitative research method to identify the barriers to rooftop solar photovoltaic adoption among households in *** face-to-face interviews with a purposively selected sample of 52 households,the research aims to gain in-depth insights into the multifaceted challenges hindering the widespread adoption of solar energy in residential *** findings reveal several key barriers:financial barriers,informational barriers,technical barriers,regulatory barriers,social barriers,and psychological *** analysis indicates that while there is a predominantly positive attitude towards solar photovoltaic adoption,there are sig-nificant concerns that still need to be *** these barriers with targeted policy interventions and public awareness campaigns could significantly enhance the adoptio

关键词： rooftop solar photovoltaic adoption barriers to solar energy residential solar systems Kerala solar initiatives qualitative analysis in renewable energy

Special issue on “Fluorescent probes”

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Frontiers of chemical Science and Engineering 2020年第1期14卷 1-3页

作者： Adam c.Sedgwick tony D.James Department of chemistry University of Texas at AustinAustinTX 78712-1224USA Department of chemistry University of BathBathBA27AYUK

Fluorescent probes are intelligently designed molecules that transform the act of binding/reacting with a target analyte into an optical signal[1,2].Their high sensitivity and specificity coupled with high spatial and temporal resolution offers a non-invasive approach to observe a specific analyte within complex biological environments in real time with high precision[3].These"molecular tools"have the capability to interrogate the role of specific biomarkers that are associated with a particular disease state or can be used to improve our understanding of the role or certain species in a biological pathway[4,5].

关键词： Fluorescent specific reacting

Primary metabolism:It’s more than what's for dinner

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Molecular Plant 2021年第8期14卷 1219-1220页

作者： Jeffrey c.Anderson scott c.Peck Department of Botany and Plant Pathology Oregon State UniversityCorvallisOR 97331USA Division of Biochemistry Christopher S Bond.Life Sciences CenterInterdisciplinary Plant GroupUniversity of Missouri-ColumbiaColumbiaMO 65211USA

At the risk of oversimplifying,plant–pathogen interactions are a battle for nutrients in the form of primary metabolic *** have *** want ***,amino acids,and organic acids are continuously being exported from source cells to supply both other plant cells and potentially beneficial microorganisms(Kim et al.,2021).Logically,plants attempt to restrict access to pathogens by withholding these nutrients upon infection;and successful pathogens have evolved strategies to restore nutrient availability(Kim et al.,2021).

关键词： simplify restrict continuously

constitutive behavior and processing maps of a new wrought magnesium alloy ZE20 (Mg-2Zn-0.2ce)

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Journal of Magnesium and Alloys 2020年第1期8卷 111-126页

作者： scott c.Sutton Alan A.Luo Department of Materials Science and Engineering The Ohio State UniversityColumbusOH 43210United States Department of Integrated Systems Engineering The Ohio State UniversityColumbusOH 43210United States Mag Specialties Inc. DenverCO 80210USA

ZE20(Mg-2Zn-0.2ce)^2 is a new wrought magnesium alloy with improved extrudability and mechanical properties[1].To understand the constitutive behavior and workability of this new alloy,Gleeble thermomechanical testing has been carried out in this *** flow stress behavior of ZE20 was investigated between 250℃–450℃ and 10^–3 s^–1–1.0 s^–1 in isothermal *** descriptions of the flow stress are provided.A new general approach at application of the extended Ludwik equation is demonstrated and was found to be more accurate than the hyperbolic sine Arrhenius model while having a similar number of model *** maps were developed based on the experimental results and are verified with microstructural investigation.A region of safe processing with non-basal texture and high activity of dynamic recrystallization(DRX)was found between 375℃ and 450℃,from 10^–1 s^–1 to 10^–2.5 s^–1.A region of potentially safe processing with annealing that is associated with shear band nucleation of non-basal grains was identified for temperatures as low as 300℃ and rates as high as 10^–1 s^–1.

关键词： Magnesium alloys Thermomechanical processing constitutive behavior Processing map Deformation mechanisms

Numerical Simulation of Free Surface by an Area-Preserving Level Set Method

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communications in computational Physics 2012年第4期11卷 1347-1371页

作者： tony W.H.Sheu c.H.Yu Department of Engineering Science and Ocean Engineering National Taiwan UniversityNo.1Sec.4Roosevelt RoadTaipeiTaiwan Taida Institute of Mathematical Sciences(TIMS) National Taiwan University center for Quantum Science and Engineering(cQSE) National Taiwan University

We apply in this study an area preserving level set method to simulate gas/water interface *** the sake of accuracy,the spatial derivative terms in the equations of motion for an incompressible fluid flow are approximated by the fifthorder accurate upwinding combined compact difference(UccD)*** scheme development employs two coupled equations to calculate the first-and second-order derivative terms in the momentum *** accurately predicting the level set value,the interface tracking scheme is also developed to minimize phase error of the first-order derivative term shown in the pure advection *** the purpose of retaining the long-term accurate Hamiltonian in the advection equation for the level set function,the time derivative term is discretized by the sixth-order accurate symplectic Runge-Kutta ***,to keep as a distance function for ensuring the front having a finite thickness for all time,the re-initialization equation is *** the verification of the optimized UccD scheme for the pure advection equation,two benchmark problems have been chosen to investigate in this *** level set method with excellent area conservation property proposed for capturing the interface in incompressible fluid flows is also verified by solving the dam-break,Rayleigh-Taylor instability,two-bubble rising in water,and droplet falling problems.

关键词： Level set method phase error upwinding combined compact scheme Hamiltonian symplectic Runge-Kutta area conservation property

A Generic Model to Estimate Wheat LAI over Growing Season Regardless of the Soil-Type Background

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Plant Phenomics 2023年第2期5卷 333-352页

作者： Qiaomin chen Bangyou Zheng Karine chenu scott c.chapman School of Agriculture and Food Sciences The University of QueenslandSt LuciaQLDAustralia Agriculture and Food CSIROQueensland Bioscience PrecinctSt LuciaQLDAustralia The University of Queensland Queensland Alliance for Agriculture and Food InnovationToowoombaQLDAustralia

It is valuable to develop a generic model that can accurately estimate the leaf area index(LAI)of wheat from unmanned aerial vehicle-based multispectral data for diverse soil backgrounds without any ground *** achieve this objective,2 strategies were investigated to improve our existing random forest regression(RFR)model,which was trained with simulations from a radiative transfer model(PROSAIL).The 2 strategies consisted of(a)broadening the reflectance domain of soil background to generate training data and(b)finding an appropriate set of indicators(band reflectance and/or vegetation indices)as inputs of the RFR *** RFR models were tested in diverse soils representing varying soil types in *** analysis indicated that adopting both strategies resulted in a generic model that can provide accurate estimation for wheat LAI and is resistant to changes in soil *** validation on 2 years of field trials,this model achieved high prediction accuracy for LAI over the entire crop cycle(LAI up to 7 m^(2)m^(−2))(root mean square error(RMSE):0.23 to 0.89 m^(2)m^(−2)),including for sparse canopy(LAI less than 0.3 m^(2)m^(−2))grown on different soil types(RMSE:0.02 to 0.25 m^(2)m^(−2)).The model reliably captured the seasonal pattern of LAI dynamics for different treatments in terms of genotypes,plant densities,and water–nitrogen managements(correlation coefficient:0.82 to 0.98).With appropriate adaptations,this framework can be adjusted to any type of sensors to estimate various traits for various species(including but not limited to LAI of wheat)in associated disciplines,e.g.,crop breeding,precision agriculture,etc.

关键词： soil Wheat breeding