Study on the Working Mechanism of Amylosucrase DrAS and Its Stability Engineering

In civil engineering in Russia, trenching for utilities is currently under digging. To perform such works, it is necessary to use high-precision construction machinery, because inaccurate performance of works can lead to the break down of existing utilities, thereby affecting the residents of nearby houses and demanding the additional works for renewal.The most universal labour saver to perform construction works is hydraulic driven single-bucket excavators, which provide up to 38% of works. Therefore, to improve technical characteristics that affect the accuracy of the work performed is an important task.High requirements for the performance of works are defined by existing construction regulations: an allowable soil layer to remain is at most 0.05 m. To fulfil such requirements, an exact assessment of the working mechanism position and a trench profile is necessary.Examination of a manually operated digging process shows that an operator provides operations untimely, however an automated control system can solve this problem. Dynamic phenomena in the working mechanism have the greatest impact on the accuracy of the works performed.To assess the bucket digging edge position accuracy, a mathematical model of the working mechanism has been created. Based on the cycle scheme of the working process, the excessive displacements of the hydraulic cylinder rods under the load are taken into account. By the end of the cycle, the difference between the specified and obtained positions along the vertical coordinate has been 0.0892 m.A dynamic error of the hydraulic drive system of the working mechanism is considered as a sum of the error due to excessive displacements of the hydraulic cylinder rods and the error due to delay of the hydraulic drive, with the latter being calculated for the average time of delay taking into account the data available in the literature. The total error of the bucket digging edge position of the working mechanism is 0.1176 m, which is 2 times more than the value of 0.05 mConformity of all the links with specification requirements does not guarantee compliance with the required displacement accuracy of the bucket digging edge, and, thus, the soil layer to remain in the base of the trench can exceed the regulated value of 0.05 m.

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The Long-Lasting Story of One Sensor Development: From Novel Ionophore Design toward the Sensor Selectivity Modeling and Lifetime Improvement

Sensors ◽

10.3390/s21041401 ◽

2021 ◽

Vol 21 (4) ◽

pp. 1401

Author(s):

Larisa Lvova ◽

Donato Monti ◽

Corrado Di Natale ◽

Roberto Paolesse

Keyword(s):

Anion Exchanger ◽

Specific Interaction ◽

Spectroscopic Studies ◽

Polymeric Membranes ◽

Polymeric Membrane ◽

Active Components ◽

Nitrite Ion ◽

Working Mechanism ◽

Axial Coordination ◽

Porphyrin Aggregation

The metalloporphyrin ligand bearing incorporated anion-exchanger fragment, 5-[4-(3-trimethylammonium)propyloxyphenyl]-10,15,20-triphenylporphyrinate of Co(II) chloride, CoTPP-N, has been tested as anion-selective ionophore in PVC-based solvent polymeric membrane sensors. A plausible sensor working mechanism includes the axial coordination of the target anion on ionophore metal center followed by the formed complex aggregation with the second ionophore molecule through positively charged anion-exchanger fragment. The UV-visible spectroscopic studies in solution have revealed that the analyte concentration increase induces the J-type porphyrin aggregation. Polymeric membranes doped with CoTPP-N showed close to the theoretical Nernstian response toward nitrite ion, preferably coordinated by the ionophore, and were dependent on the presence of additional membrane-active components (lipophilic ionic sites and ionophore) in the membrane phase. The resulting selectivity was a subject of specific interaction and/or steric factors. Moreover, it was demonstrated theoretically and confirmed experimentally that the selection of a proper ratio of ionophore and anionic additive can optimize the sensor selectivity and lifetime.

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Rural Development Through Non-State Actors in Highlands of Pakistan

SAGE Open ◽

10.1177/21582440211007126 ◽

2021 ◽

Vol 11 (2) ◽

pp. 215824402110071

Author(s):

Muhammad Luqman ◽

Saleem Ashraf ◽

Babar Shahbaz ◽

Tahir Munir Butt ◽

Raheel Saqib

Keyword(s):

Rural Development ◽

Mixed Methods Research ◽

Religious Faith ◽

Research Area ◽

Working Mechanism ◽

Test Analysis ◽

State Institutions ◽

Significant Difference ◽

State Actors ◽

Household Heads

We explored the contribution and effectiveness of state and non-state institutions in rural development efforts in highlands (Khyber Pakhtunkhwa [KPK] province) of Pakistan. This study employed mixed-methods research design and data were collected from 300 household heads, randomly selected from six villages from two purposively selected districts Mansehra and Nowshehra. Findings showed people in KPK were deprived of due to conflicts, conspiracies and terrorism, poor governance, small landholdings and subsistence farming followed by sluggish marketing system, insufficient education and training for people, and inadequate employment opportunities. Regarding contribution, non-state institutions had more contribution as compared to state institutions. T-test analysis showed that the non-state institutions had an effective provision of agricultural extension and forestry advisory services, education, health services in remote areas, skill development, and provision of microcredit schemes. The results of F-test statistics showed highly significant difference among the perceived effectiveness of rural development activities of different types of non-state actors (localite, cosmopolite, and religious/faith-based) working in the research area. This study recommends state-owned rural development departments revisit their working mechanism and develop synergistic working relationship with the non-state institutions in discharging rural development efforts.

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An Overview of Molecular Dynamic Simulation for Corrosion Inhibition of Ferrous Metals

Metals ◽

10.3390/met11010046 ◽

2020 ◽

Vol 11 (1) ◽

pp. 46

Author(s):

Nur Izzah Nabilah Haris ◽

Shafreeza Sobri ◽

Yus Aniza Yusof ◽

Nur Kartinee Kassim

Keyword(s):

Molecular Dynamic ◽

Corrosion Inhibition ◽

High Performance ◽

Md Simulation ◽

Ferrous Metal ◽

Working Mechanism ◽

Inhibitor Molecule ◽

As Adsorption ◽

Inhibition Studies ◽

Selection Of

Molecular dynamics (MD) simulation is a powerful tool to study the molecular level working mechanism of corrosion inhibitors in mitigating corrosion. In the past decades, MD simulation has emerged as an instrument to investigate the interactions at the interface between the inhibitor molecule and the metal surface. Combined with experimental measurement, theoretical examination from MD simulation delivers useful information on the adsorption ability and orientation of the molecule on the surface. It relates the microscopic characteristics to the macroscopic properties which enables researchers to develop high performance inhibitors. Although there has been vast growth in the number of studies that use molecular dynamic evaluation, there is still lack of comprehensive review specifically for corrosion inhibition of organic inhibitors on ferrous metal in acidic solution. Much uncertainty still exists on the approaches and steps in performing MD simulation for corrosion system. This paper reviews the basic principle of MD simulation along with methods, selection of parameters, expected result such as adsorption energy, binding energy and inhibitor orientation, and recent publications in corrosion inhibition studies.

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The Effects of Molecular Packing Behavior of Small-Molecule Acceptors in Ternary Organic Solar Cells

Applied Sciences ◽

10.3390/app11020755 ◽

2021 ◽

Vol 11 (2) ◽

pp. 755

Author(s):

Eunhee Lim

Keyword(s):

Solar Cells ◽

Energy Level ◽

Ternary System ◽

Small Molecule ◽

Organic Solar Cells ◽

Orbital Energy ◽

Working Mechanism ◽

Energy Level Structure ◽

The Third ◽

Molecular Backbone

Herein, two diketopyrrolopyrrole (DPP)-based, small-molecule isomers, o- and p-DPP-PhCN, were introduced as acceptors in ternary organic solar cells (OSCs). The isomers have the same molecular backbone but differ in the positions of the cyanide (CN) substituents (ortho and para), which greatly affects their packing behavior. Ternary solar cells composed of poly(3-hexylthiophene) (P3HT):DPP-PhCN:phenyl-C61-butyric acid methyl ester (PCBM) were fabricated, and the effects of the different packing behaviors of the third component on the device performance and the working mechanism of the ternary cells were investigated. The addition of o-DPP-PhCN with a relatively high-lying lowest unoccupied molecular orbital energy level resulted in an increase in the open-circuit voltage (VOC) in the ternary devices, demonstrating the alloy-like structure of the two acceptors (o-DPP-PhCN and PCBM) in the ternary system. However, the p-DPP-PhCN-based ternary cells exhibited VOC values similar to that of a P3HT:PCBM binary cell, irrespective of the addition of p-DPP-PhCN, indicating a cascade energy-level structure in the ternary system and an effective charge transfer from the P3HT to the PCBM. Importantly, by increasing the addition of p-DPP-PhCN, the short-circuit current density increased substantially, resulting in pronounced shoulder peaks in the external quantum efficiency responses in the long-wavelength region, corresponding to the contribution of the photocurrent generated by the light absorption of p-DPP-PhCN. Despite sharing the same molecular backbone, the two DPP-PhCNs exhibited substantially different packing behaviors according to the position of their CN substituents, which also greatly affected the working mechanism of the ternary devices fabricated using the DPP-PhCNs as the third component.

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Optimum Design of the Working Mechanism of Loader with Ant Colony Algorithm (ACA)

2007 International Conference on Mechatronics and Automation ◽

10.1109/icma.2007.4304050 ◽

2007 ◽

Cited By ~ 2

Author(s):

Rongyi Zhang ◽

Jianjia Qi ◽

Yu Cai

Keyword(s):

Optimum Design ◽

Ant Colony Algorithm ◽

Ant Colony ◽

Working Mechanism

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Study on Water Cushion Belt Conveyor

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1016.14 ◽

2014 ◽

Vol 1016 ◽

pp. 14-18

Author(s):

Xian Wei Liu ◽

Jia Sheng Wang ◽

Lan Tao Wu ◽

Xin Zhang ◽

Hua Cheng

Keyword(s):

Reynolds Equation ◽

Belt Conveyor ◽

Working Mechanism ◽

Film Properties ◽

Practical Applications ◽

Lubrication Equation ◽

Start Up ◽

New Type ◽

Air Cushion ◽

Lubricating Mechanism

Based on air cushion belt conveyor, a new type of belt conveyor named water cushion belt conveyor is proposed. It has a wide scope of applications for its features such as stability and reliability, capability of full load start-up, and environment-friendliness. This paper studies the working mechanism and lubricating mechanism of the water cushion belt conveyor. The basic lubrication equation of the water cushion is deduced from the universal form of the Reynolds equation used to study the pressure film properties of the water cushion. The design of the key part of the water cushion device is described in details. The research can be taken as a reference in practical applications.

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Numerical Investigation of the Coulter Principle in a Microfluidic Device

Volume 2, Fora: Cavitation and Multiphase Flow; Fluid Measurements and Instrumentation; Microfluidics; Multiphase Flows: Work in Progress ◽

10.1115/fedsm2013-16011 ◽

2013 ◽

Author(s):

Muheng Zhang ◽

Yongsheng Lian

Keyword(s):

Electric Field ◽

Stokes Equations ◽

Equations Of Motion ◽

Navier Stokes ◽

Working Mechanism ◽

Navier Stokes Equations ◽

Sheath Flow ◽

Coulter Counters ◽

Pass Through ◽

Cell Motion

Coulter counters are analytical microfluidic instrument used to measure the size and concentration of biological cells or colloid particles suspended in electrolyte. The underlying working mechanism of Coulter counters is the Coulter principle which relies on the fact that when low-conductive cells pass through an electric field these cells cause disturbances in the measurement (current or voltage). Useful information about these cells can be obtained by analyzing these disturbances if an accurate correlation between the measured disturbances and cell characteristics. In this paper we use computational fluid dynamics method to investigate this correlation. The flow field is described by solving the Navier-Stokes equations, the electric field is represented by a Laplace’s equation in which the conductivity is calculated from the Navier-Stokes equations, and the cell motion is calculated by solving the equations of motion. The accuracy of the code is validated by comparing with analytical solutions. The study is based on a coplanar Coulter counter with three inlets that consist of two sheath flow inlet and one conductive flow inlet. The effects of diffusivity, cell size, sheath flow rate, and cell geometry are discussed in details. The impacts of electrode size, gap between electrodes and electrode location on the measured distribution are also studied.

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