Test methods for the characterization of organic transistor-based ring oscillators

Background and Objectives: The resistance of microbes against anti-bacteriological drugs leading to countless deaths and terminal ailments remains a basis for concern. Hence, the main interest of this study was to design, synthesize and report unusual compounds with basic hydrophilic moieties plus hydrophobic functions for anti-bacteriological studies. Materials and Methods: Analytical (melting points, micro-analysis (C. H.N.S) magnetic susceptibility (µeff), molar conductance plus solubility test) methods; spectral (Fourier Transform Infrared(FTIR)), electrospray ionization mass spectrometry (ESI-MS), nuclear magnetic resonance (1H- plus 13C-NMR), electronic(UV-Vis)) measurements; theoretical (DFT) evaluations were utilized for the characterization of the chelator and its chelates. All synthesized compounds were examined for antimicrobial and antioxidant potentials while the chelator was singly evaluated for solvent extractive capacity. Results: A nitrogenous based chelator-ligand, (E)-1-(((4,6-dimethylpyrimidin-2-yl)imino)methyl) naphthalen-2-ol(LH) synthesized through reflux-condensation reaction of 2-amino-4,6-dimethylpyrimidine with 2-hydroxy-1-napthaldehyde was acquired. Further reflux of the chelator-ligand with bivalent ions of iron-sulphate and zinc-acetate salts plus 2,2’-bipyridine resulted into separate bivalent-heteroleptic metallic chelates. The deprotonated nitrogen of the amine moiety and carbon of the carbonyl gave rise to the chelator-ligand with N2O2 chromophore detected around the metallic atom in the chelates. The µeff data plus UV-Vis spectral values of the chelates conformed to 6-coordinate octahedral geometry. All the chelates were high spin and non-ionic in dimethylsulfoxide (DMSO). The antimicrobial and antioxidant screening of the compounds presented moderate to fantastic results, while the metallic extractive proficiency of the chelator showed outstanding extractability for Fe2+ and Zn2+ions with an efficiency of 79.34% and 51.92% correspondingly. Conclusion: All the synthesized compounds are novel and demonstrated prospective biological, plus metallic ions’ extractive potentials required for designs plus isolation of products also for such actions.

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Characterizing noise barriers: SOPRANOISE half-term progress report

INTER-NOISE and NOISE-CON Congress and Conference Proceedings ◽

10.3397/in-2021-2485 ◽

2021 ◽

Vol 263 (3) ◽

pp. 3663-3674

Author(s):

Jean-Pierre Clairbois ◽

Massimo Garai ◽

Wolfram Bartolomaeus ◽

Michael Chudalla ◽

Fabio Strigari ◽

...

Keyword(s):

Test Methods ◽

Progress Report ◽

Physical Significance ◽

Final Report ◽

Noise Barriers ◽

Railway Noise ◽

Development Phases ◽

Effective Use

SOPRANOISE targets simplified assessment of the in-situ intrinsic acoustic performances of road / railway noise barriers. This paper presents its half-term progress. The research is divided in 5 Work Packages, the scientific ones being WP2 to WP5.WP2 is about establishing a state of art (SoA) of the intrinsic performances characterization: it is now finished and presented in 2 other papers by Conter and Fuchs. WP3 is about in-situ inspection tools: based on a review / questionnaire, an inspection protocol has been developed allowing simplified assessments mainly based on visual inspections and characterization of possible defects; WP3 is now in its final testing phase. WP4 is about designing a brand new "quick and safe methods" that could take place "in between" the inspection tools and the standardized EN1793-5 and 6; the research and development phases of WP4 are now finished, while its validation along highways is now scheduled. Finally, WP5 is about the use of noise barriers in the European market and the final report: a synthesis on the physical behavior of noise barriers and the physical significance of the test methods has been done, as well a SoA on the effective use of noise barriers; the results will be presented.

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Expedited Testing Program for Performance Characterization of Asphalt Mixtures

Transportation Research Record Journal of the Transportation Research Board ◽

10.1177/0361198119857033 ◽

2019 ◽

Vol 2673 (12) ◽

pp. 225-233

Author(s):

Intikhab Haidar ◽

Charles W. Schwartz ◽

Sadaf Khosravifar

Keyword(s):

Permanent Deformation ◽

Performance Testing ◽

Testing Procedure ◽

Test Methods ◽

Asphalt Mixtures ◽

Test Specifications ◽

Research Grade ◽

Repeated Load ◽

Lengthy Process

The past two decades have seen significant efforts to standardize a series of simplified test methods to characterize the dynamic modulus (DM) and repeated load permanent deformation (RLPD) performance characteristics of asphalt mixtures using the asphalt mixtures performance tester (AMPT). While the current AASHTO T 79 test specifications for the AMPT are faster and easier to perform than their preceding research grade test protocols, there is still reluctance among highway agencies and industry to conduct performance testing using the AMPT. One significant reason is the lengthy process of sample preparation and testing for the DM and RLPD tests. Two studies to expedite this process are reported here. First, the potential for abbreviating the DM testing procedure was examined. It provides the option to fully exclude testing at 40°C by adding an additional frequency of 0.01 Hz at 20°C. This approach reduces time for testing as well as for sample conditioning at high temperature. Second, the possibility of reducing the total number of required specimens was evaluated. The variation of the DM under repetitive testing and the appropriateness of performing the RLPD test on samples already tested for DM were evaluated. The results showed that specimen damage or densification because of DM testing is insignificant. As a consequence, DM test specimens can be re-used for RLPD testing, reducing the required number of samples from 12 to 9.

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Production and Characterization of Hybrid Briquettes from Corncobs and Oil Palm Trunk Bark under a Low Pressure Densification Technique

Sustainability ◽

10.3390/su12062468 ◽

2020 ◽

Vol 12 (6) ◽

pp. 2468

Author(s):

Sunday Yusuf Kpalo ◽

Mohamad Faiz Zainuddin ◽

Latifah Abd Manaf ◽

Ahmad Muhaimin Roslan

Keyword(s):

Rural Communities ◽

Mechanical Strength ◽

Oil Palm ◽

Compaction Pressure ◽

Low Pressure ◽

Economic Benefits ◽

Test Methods ◽

Mechanical And Thermal Properties ◽

Oil Palm Trunk

The objective of this research was to investigate the quality of hybrid briquettes developed from corncobs (CC) and oil palm trunk bark (OPTB) under a low-pressure densification technique. The materials were combined in varying ratios of CC to OPTB (100:0, 75:25, 50:50, 25:75, 0:100) and wastepaper pulp (10% by weight) was added to each mixture as a binder. The briquettes were produced using a manually operated 20-tonne hydraulic piston press at 28 °C temperature and ≤7 MPa compaction pressure. The mechanical strength of the briquettes was determined by the drop test and compression test methods, while a bomb calorimeter was used to determine the calorific values. The results showed that the physical properties of hybrid briquettes ranged from 9.24–10.00% moisture content, 0.38–0.40 g/cm3 density, and 87.60%–92.00% water resistance. Mechanical strength showed a 98.28%–99.08% shatter index and 18.47–21.75 MPa compressive strength, while calorific values ranged from 16.54–16.91 MJ/kg. The hybrid briquettes fared better than the CC briquettes. The significance of this study lies in the production of briquettes with suitable physical, mechanical and thermal properties by utilizing OPTB which have hitherto not been used, mixed with corncobs. This could bring substantial environmental and socio-economic benefits to rural communities of the developing countries.

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