The Mechanics and Stability of Gold Nanoparticle-Oligo-Ligand-DNA Systems

2013 ◽  
Vol 1513 ◽  
Author(s):  
Letisha A. McLaughlin ◽  
Mohammed A. Zikry
Keyword(s):  
Gold Nanoparticles ◽  
Dislocation Density ◽  
Large Scale ◽  
Mechanical Stability ◽  
Compressive Loading ◽  
High Stress ◽  
System Stability ◽  
Interfacial Behavior ◽  
Thiol Ligands ◽  
The Stability

ABSTRACTSystems in which DNA is adsorbed onto gold nanoparticles have the potential for applications in gene regulation therapies, drug delivery, sensing, and DNA scaffolding. However, the mechanical stability of gold nanoparticles (AuNPs) and interfacial behavior between the gold nanoparticles and thiol ligands are not well understood or quantified. The stability of DNA-AuNP) systems is, therefore, examined using a large-scale specialized finite-element approach with a dislocation-density based crystalline plasticity framework to model the AuNPs and an elastic description to model thiol ligands, DNA, and the ionic solution. For compressive loading conditions, the system exhibited morphological instabilities in the nanoparticles, as well as high stress and dislocation-density gradients at the thiol-nanoparticle attachment sites, which can affect system stability and attachment strength.

scholarly journals Large Photovoltaic Power Plants Integration: A Review of Challenges and Solutions

Energies ◽  
2019 ◽  
Vol 12 (19) ◽  
pp. 3798 ◽  
Author(s):  
Mansouri ◽  
Lashab ◽  
Sera ◽  
Guerrero ◽  
Cherif
Keyword(s):  
System Integration ◽  
Power Plants ◽  
Large Scale ◽  
System Stability ◽  
Pv System ◽  
Pv Systems ◽  
Large Scale Integration ◽  
Voltage Limit ◽  
The Stability ◽  
Scale Integration

Renewable energy systems (RESs), such as photovoltaic (PV) systems, are providing increasingly larger shares of power generation. PV systems are the fastest growing generation technology today with almost ~30% increase since 2015 reaching 509.3 GWp worldwide capacity by the end of 2018 and predicted to reach 1000 GWp by 2022. Due to the fluctuating and intermittent nature of PV systems, their large-scale integration into the grid poses momentous challenges. This paper provides a review of the technical challenges, such as frequency disturbances and voltage limit violation, related to the stability issues due to the large-scale and intensive PV system penetration into the power network. Possible solutions that mitigate the effect of large-scale PV system integration on the grid are also reviewed. Finally, power system stability when faults occur are outlined as well as their respective achievable solutions.

Dynamic Stability Research On the DCT Marine Propulsion System with Unsymmetrical Load

2021 ◽  
Author(s):  
Jianghai Xu ◽  
Chunxiao Jiao ◽  
Donglin Zou ◽  
na ta ◽  
Zhushi Rao
Keyword(s):  
Large Scale ◽  
Excitation Frequency ◽  
Load Ratio ◽  
Coupled System ◽  
Propulsion System ◽  
System Stability ◽  
Unstable State ◽  
Finite Width ◽  
Gear Pair ◽  
The Stability

Abstract The DCT (double-cylinder turbines) propulsion system is widely applied to large-scale ships, while the instability mechanism of the system lacks theoretical and scientific research. Based on gear transmission principle and finite width journal bearings theory, the lateral-torsional-axial model of the system considering multiple nonlinear and time-varying factors is established. The effects of the unsymmetrical load parameters on the stability of the coupled system have been explored and quantified. Results indicate that the phenomenon of instability gradually occurs with the increase of excitation frequency, the decrease of load ratio between the two inputs or the decrease of input load value, and the vibration of the gear pair on the low load side is more severe. Furthermore, the vibration amplitude is not only related to the load parameters but also the distance between the gear pair and the load input disc. Finally, the influence of the oil whip on the system stability is crucial, especially when the system is in an unstable state. This study provides a theoretical reference for the optimization and adjustment of such propulsion system.

scholarly journals Impedance-Based Stability Analysis of Paralleled Grid-Connected Rectifiers: Experimental Case Study in a Data Center

Energies ◽  
2020 ◽  
Vol 13 (8) ◽  
pp. 2109 ◽  
Author(s):  
Henrik Alenius ◽  
Tomi Roinila
Keyword(s):  
Stability Analysis ◽  
Data Center ◽  
Large Scale ◽  
Real Life ◽  
System Stability ◽  
Limited Information ◽  
Impedance Measurements ◽  
Grid Connected Converters ◽  
The Stability

Grid-connected systems often consist of several feedback-controlled power-electronics converters that are connected in parallel. Consequently, a number of stability issues arise due to interactions among multiple converter subsystems. Recent studies have presented impedance-based methods to assess the stability of such large systems. However, only few real-life experiences have been previously presented, and practical implementations of impedance-based analysis are rare for large-scale systems that consist of multiple parallel-connected devices. This work presents a case study in which an unstable high-frequency operation, caused by multiple paralleled grid-connected rectifiers, of a 250 kW data center in southern Finland is reported and studied. In addition, the work presents an experimental approach for characterizing and assessing the system stability by using impedance measurements and an aggregated impedance-based analysis. Recently proposed wideband-identification techniques based on binary injection and Fourier methods are applied to obtain the experimental impedance measurements from the input terminals of a single data center rectifier unit. This work provides a practical approach to design and implement the impedance-based stability analysis for a system consisting of multiple paralleled grid-connected converters. It is shown that the applied methods effectively predict the overall system stability and the resonant modes of the system, even with very limited information on the system. The applied methods are versatile, and can be utilized in various grid-connected applications, for example, in adaptive control, system monitoring, and stability analysis.

Deformation Mechanism of the Mountain and Research of Reinforcement in Yanchi Mountain

2011 ◽  
Vol 71-78 ◽  
pp. 1429-1434
Author(s):  
Rui Wang ◽  
Ke Jian Li ◽  
Qiu Yuan Liu ◽  
Yan Qiu
Keyword(s):  
Large Scale ◽  
High Stress ◽  
Mining Activities ◽  
Obvious Effect ◽  
Significant Evidence ◽  
Stress Zone ◽  
The Stability ◽  
The Cost ◽  
High Stress Zone ◽  
Strengthening Method

Mining activities would generate large scale goaf, and the existing of goaf makes the mountain body produce great distortion. Therefore, it has become a kind of serious geological hazard. Based on the concrete conditions of Yanchi Mountain, the simulation with ANSYS was conducted for analyzing the stability of goaf, mine pillar and roof, which would find out the high stress zone and plastic zone of the goaf. Therefore, the conclusion that inadequate of the pillar strength is the main cause of the mountain deformation is drawn, and a new strengthening method which is to strengthen the mine pillar and to increase new mine pillars is put forward on basis of the conclusion.The results show that the strengthening method has an obvious effect, and it reduces the workload and the cost, which also provides very significant evidence for the future studying.

Large Scale Triaxial Rheological Apparatus Development and Granular Soils Rheological Properties Analysis

2011 ◽  
Vol 90-93 ◽  
pp. 79-89 ◽  
Author(s):  
Xiao Bin Chen ◽  
Jia Sheng Zhang
Keyword(s):  
Rheological Properties ◽  
Stress Level ◽  
Large Scale ◽  
High Stress ◽  
Confining Pressure ◽  
Granular Soil ◽  
Axial Pressure ◽  
Creep Tests ◽  
Creep Properties ◽  
The Stability

To study the granular soil’s rheological properties, a large triaxial rheological apparatus was developed by assemblying a axial pressure and confining pressure providing equipments for the SZ30-4 large scale triaxial apparatus, and the stability examinations proved that the stability of this pressure providing equipments was competent for granular soil’s rheological tests. The large triaxial rheological apparatus have the axial pressure ranging from 0 to 1.0 MPa, confining pressure of 50kPa, 100kPa, 150kPa, 200kPa, 250kPa and the soil sample dimension of Φ=300mm, h=600mm. A series of granular soil creep tests were executed on this apparatus. The tests discussion shows that stress conditions are the main factors, which affects the creep properties of granular soil. There are different rheological properties at different stress level. eg. at low stress level (S=0.1) for the elastic, at middling stress level (0.2<S≤0.6) for the linear viscoelastic and at high stress level (S>0.8) for the non-linear viscous plastic. The total rheological strain nonlinearly increase with stress level increments but linearly increase with confining pressure increments. According to the discussion of redstone granular soil’s creep properties, a rheological component based on hyperbola function was presented, and a nonlinear viscous elastioplastic rheological constitutive model was set up by putting the component and the Burgers model in series. The creep properties analysis shows the rheological model can describe the granular soil’s whole rheological phase well.

An analysis of the transport properties and mechanical stability of rapidly solidified Al-Sb alloy

2015 ◽  
Vol 10 (2) ◽  
pp. 2663-2681
Author(s):  
Rizk El- Sayed ◽  
Mustafa Kamal ◽  
Abu-Bakr El-Bediwi ◽  
Qutaiba Rasheed Solaiman
Keyword(s):  
Mechanical Properties ◽  
Thermal Conductivity ◽  
Melt Spinning ◽  
Elastic Moduli ◽  
Mechanical Stability ◽  
Microstructural Analysis ◽  
Alloy System ◽  
Antimony Content ◽  
The Stability ◽  
Rapidly Solidified

The structure of a series of AlSb alloys prepared by melt spinning have been studied in the as melt–spun ribbons  as a function of antimony content .The stability  of these structures has  been  related to that of the transport and mechanical properties of the alloy ribbons. Microstructural analysis was performed and it was found that only Al and AlSb phases formed for different composition.  The electrical, thermal and the stability of the mechanical properties are related indirectly through the influence of the antimony content. The results are interpreted in terms of the phase change occurring to alloy system. Electrical resistivity, thermal conductivity, elastic moduli and the values of microhardness are found to be more sensitive than the internal friction to the phase changes. 

scholarly journals Development and Characterization of Two Types of Surface Displayed Levansucrases for Levan Biosynthesis

Catalysts ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 757
Author(s):  
Huiyi Shang ◽  
Danni Yang ◽  
Dairong Qiao ◽  
Hui Xu ◽  
Yi Cao
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Molecular Weight ◽  
Large Scale ◽  
Surface Display ◽  
Yeast Surface Display ◽  
Fusion Partner ◽  
Whole Cell ◽  
Food Industries ◽  
Yeast Surface ◽  
The Stability

Levan has wide applications in chemical, cosmetic, pharmaceutical and food industries. The free levansucrase is usually used in the biosynthesis of levan, but the poor reusability and low stability of free levansucrase have limited its large-scale use. To address this problem, the surface-displayed levansucrase in Saccharomyces cerevisiae were generated and evaluated in this study. The levansucrase from Zymomonas mobilis was displayed on the cell surface of Saccharomyces cerevisiae EBY100 using a various yeast surface display platform. The N-terminal fusion partner is based on a-agglutinin, and the C-terminal one is Flo1p. The yield of levan produced by these two whole-cell biocatalysts reaches 26 g/L and 34 g/L in 24 h, respectively. Meanwhile, the stability of the surface-displayed levansucrases is significantly enhanced. After six reuses, these two biocatalysts retained over 50% and 60% of their initial activities, respectively. Furthermore, the molecular weight and polydispersity test of the products suggested that the whole-cell biocatalyst of levansucrase displayed by Flo1p has more potentials in the production of levan with low molecular weight which is critical in certain applications. In conclusion, our method not only enable the possibility to reuse the enzyme, but also improves the stability of the enzyme.

scholarly journals INTRACISTRONIC MAPPING OF ELECTROPHORETIC SITES IN DROSOPHILA MELANOGASTER: FIDELITY OF INFORMATION TRANSFER BY GENE CONVERSION

Genetics ◽  
1974 ◽  
Vol 76 (2) ◽  
pp. 289-299
Author(s):  
Margaret McCarron ◽  
William Gelbart ◽  
Arthur Chovnick
Keyword(s):  
Drosophila Melanogaster ◽  
Information Transfer ◽  
Large Scale ◽  
Genetic Basis ◽  
Xanthine Dehydrogenase ◽  
Specific Protein ◽  
Wild Type ◽  
Electrophoretic Variation ◽  
The Stability ◽  
Recombination Experiments

ABSTRACT A convenient method is described for the intracistronic mapping of genetic sites responsible for electrophoretic variation of a specific protein in Drosophila melanogaster. A number of wild-type isoalleles of the rosy locus have been isolated which are associated with the production of electrophoretically distinguishable xanthine dehydrogenases. Large-scale recombination experiments were carried out involving null enzyme mutants induced on electrophoretically distinct wild-type isoalleles, the genetic basis for which is followed as a nonselective marker in the cross. Additionally, a large-scale recombination experiment was carried out involving null enzyme rosy mutants induced on the same wild-type isoallele. Examination of the electrophoretic character of crossover and convertant products recovered from the latter experiment revealed that all exhibited the same parental electrophoretic character. In addition to documenting the stability of the xanthine dehydrogenase electrophoretic character, this observation argues against a special mutagenesis hypothesis to explain conversions resulting from allele recombination studies.

Stability of Ring-Type MEMS Gyroscopes Subjected to Stochastic Angular Speed Fluctuation

2017 ◽  
Vol 139 (4) ◽  
Author(s):  
Samuel F. Asokanthan ◽  
Soroush Arghavan ◽  
Mohamed Bognash
Keyword(s):  
Angular Velocity ◽  
Degrees Of Freedom ◽  
Microelectromechanical Systems ◽  
Damping Ratio ◽  
Operating Conditions ◽  
System Stability ◽  
System Response ◽  
Ring Type ◽  
Mems Gyroscopes ◽  
The Stability

Effect of stochastic fluctuations in angular velocity on the stability of two degrees-of-freedom ring-type microelectromechanical systems (MEMS) gyroscopes is investigated. The governing stochastic differential equations (SDEs) are discretized using the higher-order Milstein scheme in order to numerically predict the system response assuming the fluctuations to be white noise. Simulations via Euler scheme as well as a measure of largest Lyapunov exponents (LLEs) are employed for validation purposes due to lack of similar analytical or experimental data. The response of the gyroscope under different noise fluctuation magnitudes has been computed to ascertain the stability behavior of the system. External noise that affect the gyroscope dynamic behavior typically results from environment factors and the nature of the system operation can be exerted on the system at any frequency range depending on the source. Hence, a parametric study is performed to assess the noise intensity stability threshold for a number of damping ratio values. The stability investigation predicts the form of threshold fluctuation intensity dependence on damping ratio. Under typical gyroscope operating conditions, nominal input angular velocity magnitude and mass mismatch appear to have minimal influence on system stability.

Sign in / Sign up

Export Citation Format

Share Document