scholarly journals Potential Use of Rice Husk Ash (RHA) in Flowable Fill Concrete

2019 ◽  
Vol 271 ◽  
pp. 07010
Author(s):  
Kazi Islam ◽  
Zahid Hossain

Flowable fill is a self-compacting material, which has been developed in recent years. It is a relatively new construction technology where rapid construction is needed for different applications such as backfilling walls, sewer trenches, bridge abutments, conduit trenches, pile excavations, and retaining walls. The objective of this study is to evaluate the usage of RHA in producing low strength and self-consolidating flowable fill concrete (FFC). Two different RHA samples (600 µm and 150 µm) in three different percentages (40%, 60%, and 80% by the weight) of Ordinary Portland Cement (OPC) have been used to prepare flowable fill mixture. The evaluation processes of these fresh FFC mixtures includes determination of strength, setting time, flowability, unit weight, and air content in the laboratory. Further, two field demonstration projects have been planned to evaluate their workability, placement, and in-service performance. Findings of this study will help the transportation and the construction agencies in finding a cost-effective construction material.

2018 ◽  
pp. 44-47
Author(s):  
F.J. Тurayev

In this paper, mathematical model of nonlinear vibration problems with fluid flows through pipelines have been developed. Using the Bubnov–Galerkin method for the boundary conditions, the resulting nonlinear integro-differential equations with partial derivatives are reduced to solving systems of nonlinear ordinary integro-differential equations with both constant and variable coefficients as functions of time.A system of algebraic equations is obtained according to numerical method for the unknowns. The influence of the singularity of heredity kernels on the vibrations of structures possessing viscoelastic properties is numerically investigated.It was found that the determination of the effect of viscoelastic properties of the construction material on vibrations of the pipeline with a flowing liquid requires applying weakly singular hereditary kernels with an Abel type singularity.


2019 ◽  
Author(s):  
Nilanjan Sengupta

Building construction sector can play a major role in reducing Greenhouse Gas emission through application of technologies aimed at reduction of use of building materials. Energy consumed during production of building materials and components plays a crucial role in creating environmental pollution. India is witnessing high growth in urban and rural housing, which needs more production of building materials. Permanent or semi-permanent type buildings which consume easily available conventional materials like brick, reinforced cement concrete etc. can be made Economic and Eco-friendly by lowering use of energy-consuming building materials through Cost-effective Construction Technologies. Buildings with Cost-effective Construction Technology can be designed within the parameters of the existing Indian Standards. Awareness generation among the users, proper technical and architectural guidance and easy availability of skilled manpower are of utmost importance for promotion of cost-effective technologies in India and to make them as the most acceptable case of sustainable building technologies both in terms of cost and environment.


2020 ◽  
Vol 16 (7) ◽  
pp. 924-932
Author(s):  
Yasmeen Mutlaq Ghazi Al Shamari ◽  
Saikh Mohammad Wabaidur ◽  
Abdulrahman Abdullah Alwarthan ◽  
Moonis Ali Khan ◽  
Masoom Raza Siddiqui

Background : A new method has been developed for the determination of food dye tartrazine in soft drinks. Tartrazine is determined by hyphenated technique Ultra Performance Liquid Chromatography coupled with Mass spectrometry. The solid-phase extraction was used for the extraction of tartrazine. Methods: For the LC-MS analysis of tartrazine acetonitrile, water (80:20) was used as a mobile phase whereas, the C-18 column was selected as the stationary phase. The chromatographic run was allowed for 1 min. The adsorbent of the solid-phase extraction was synthesized from the waste corn cob. Results: Method found to be linear in the range of 0.1 mg L-1 - 10 mg L-1, limits of detection and quantitation were found to be 0.0165 mgL-1 and 0.055 mgL-1, respectively. Tartrazine, in the real sample, was found to be 20.39 mgL-1 and 83.26 mgL-1. Conclusion: The developed UPLC-MS method is rapid, simple, precise and can be used for the quantitative analysis of tartrazine. The solid-phase extraction also involves a cost-effective procedure for extraction as it does not involve the commercial cartridge.


Antibiotics ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 298
Author(s):  
Alexander Ecke ◽  
Rudolf J. Schneider

Contamination of waters with pharmaceuticals is an alarming problem as it may support the evolution of antimicrobial resistance. Therefore, fast and cost-effective analytical methods for potential on-site analysis are desired in order to control the water quality and assure the safety of its use as a source of drinking water. Antibody-based methods, such as the enzyme-linked immunosorbent assay (ELISA), can be helpful in this regard but can also have certain pitfalls in store, depending on the analyte. As shown here for the class of β-lactam antibiotics, hydrolysis of the β‑lactam ring is a key factor in the immunochemical analysis as it influences antibody recognition. With the antibody used in this study, the limit of detection (LOD) in the immunoassay could be significantly reduced by hydrolysis for the five tested penicillins, with the lowest LOD for carbenicillin (0.2 nmol/L) and the greatest impact on penicillins G and V (reduction by 85%). In addition to enhanced quantification, our strategy also provides access to information about the degree of hydrolysis in water samples as shown for the most abundant penicillin amoxicillin.


2021 ◽  
pp. 107754632110069
Author(s):  
Sandeep Sony ◽  
Ayan Sadhu

In this article, multivariate empirical mode decomposition is proposed for damage localization in structures using limited measurements. Multivariate empirical mode decomposition is first used to decompose the acceleration responses into their mono-component modal responses. The major contributing modal responses are then used to evaluate the modal energy for the respective modes. A damage localization feature is proposed by calculating the percentage difference in the modal energies of damaged and undamaged structures, followed by the determination of the threshold value of the feature. The feature of the specific sensor location exceeding the threshold value is finally used to identify the location of structural damage. The proposed method is validated using a suite of numerical and full-scale studies. The validation is further explored using various limited measurement cases for evaluating the feasibility of using a fewer number of sensors to enable cost-effective structural health monitoring. The results show the capability of the proposed method in identifying as minimal as 2% change in global modal parameters of structures, outperforming the existing time–frequency methods to delineate such minor global damage.


Biosensors ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 85
Author(s):  
Wassa Waiwinya ◽  
Thitirat Putnin ◽  
Dechnarong Pimalai ◽  
Wireeya Chawjiraphan ◽  
Nuankanya Sathirapongsasuti ◽  
...  

An immobilization-free electrochemical sensor coupled with a graphene oxide (GO)-based aptasensor was developed for glycated human serum albumin (GHSA) detection. The concentration of GHSA was monitored by measuring the electrochemical response of free GO and aptamer-bound GO in the presence of glycated albumin; their currents served as the analytical signals. The electrochemical aptasensor exhibited good performance with a base-10 logarithmic scale. The calibration curve was achieved in the range of 0.01–50 µg/mL. The limit of detection (LOD) was 8.70 ng/mL. The developed method was considered a one-drop measurement process because a fabrication step and the probe-immobilization process were not required. This simple sensor offers a cost-effective, rapid, and sensitive detection method, and could be an alternative approach for determination of GHSA levels.


RSC Advances ◽  
2021 ◽  
Vol 11 (20) ◽  
pp. 12227-12234
Author(s):  
Hisham S. M. Abd-Rabboh ◽  
Abd El-Galil E. Amr ◽  
Elsayed A. Elsayed ◽  
Ahmed Y. A. Sayed ◽  
Ayman H. Kamel

Robust, reliable and cost-effective paper-based analytical device for potentiometric pholcodine (opiate derivative drug) ion sensing has been prepared and characterized.


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