THEORETICAL AND METHODOLOGICAL BASIS OF CREATING POLYFUNCTIONAL MODIFIERS OF MASS CONCRETES FOR RECONSTRUCTION WORKS

Author(s):  
Косухин ◽  
Mikhail Kosukhin ◽  
Косухин ◽  
Andrey Kosukhin

The findings of the known research in the sphere of concretes and concrete mixes chemical modification have been generalized and systematized; the theoretical statements and methodological recommendations in creating high-performance polyfunctional modifiers have been presented. It was demonstrated that the leading role in concrete modification is played nowadays by this class of additives, as their application provides concretes and concrete mixes with a set of prescribed properties for their operation in various conditions. It was pointed out that this sector is especially relevant in mass concreting, as the most widely used in conducting building and repair works and more demanding to the quality of concretes and concrete mixes. The modifiers were classified and the requirements to modifiers with account of their workability and functional use were listed. A high-performance fungicidal polyfunctional modifier for mass concretes, containing a plasticizing agent and hydration and hardening accelerator has been synthesized. The colloid-chemical properties of the obtained modifier and the properties of concretes and concrete mixes with this modifier have been researched.

2013 ◽  
pp. 215-218
Author(s):  
Robert O. Hatch ◽  
Craig M. Giles ◽  
Jay S. Creiglow ◽  
David R. Smith

The use of sodium propylene glycol for thick juice storage was investigated at Spreckels Sugar Company, in Brawley, California (USA). Sodium-polypropylene glycol has a density of 1.07 and does not mix with thick juice. Therefore it is suitable as a barrier layer. Chemical properties of propylene glycol, and the deposition on the top of thick juice are described. First results of the last campaign are compared with data from previous years. A significantly lower tendency in the reduction of the quality of the thick juice was found.


2020 ◽  
Vol 16 (2) ◽  
pp. 60
Author(s):  
Nwozo Sarah Onyenibe ◽  
Julius Oluwaseun Oluwafunmilola ◽  
Stanley Udogadi Nwawuba

The extracted seeds of African breadfruit are identified to be extremely healthy whenever it is correctly processed. Therefore, the aim of the present study was to evaluate the effects of processing methods on the nutritional quality of African breadfruit seed. A qualitative phytochemical analysis including: Alkaloid, Flavonoid, Saponin, Tannin, Anthraquinone, Terpenoids, Steroid, and Cardiac Glycosides for the different fraction of African breadfruit seed was performed using a standard method. The result revealed the presence and greater amount of phytochemical for the raw fraction; seven in eight, six in eight for steamed fraction, and four in eight for boiled and roasted respectively. Anti-nutrient, Proximate, and Mineral Content were also conducted using standard methods. The amino acid composition was determined using High-Performance Liquid Chromatography (HPLC). The results of the present study revealed that anti-nutrients including Phytate, Tannins, and Oxalate were significantly p<0.05 reduced in the boiled fraction 5.47±0.15, 3.42±0.02 and 6.89±0.05, and highest in the raw fraction 7.77±0.01, 5.09±0.03 and 9.34±0.14. The proximate composition including; percentage crude fat, Ash, Carbohydrate, Fatty acid, and Energy value were significantly lower p<0.05 in the boiled fraction relative to the other fractions. Mineral contents; calcium, magnesium, sodium, potassium, and phosphorus were also significantly p<0.05 elevated in the boiled fraction relative to the raw, steamed, and roasted fraction. The amino acid composition was highest in the roasted and boiled fraction 57.350 and 56.978, and lowest in the steamed and raw fraction 35.754 and 28.748 respectively. Therefore, boiling (cooking) is encouraged for the preparation of African breadfruit seed.


2003 ◽  
Vol 42 (02) ◽  
pp. 185-189 ◽  
Author(s):  
R. Haux ◽  
C. Kulikowski ◽  
A. Bohne ◽  
R. Brandner ◽  
B. Brigl ◽  
...  

Summary Objectives: The Yearbook of Medical Informatics is published annually by the International Medical Informatics Association (IMIA) and contains a selection of excellent papers on medical informatics research which have been recently published (www.yearbook.uni-hd.de). The 2003 Yearbook of Medical Informatics took as its theme the role of medical informatics for the quality of health care. In this paper, we will discuss challenges for health care, and the lessons learned from editing IMIA Yearbook 2003. Results and Conclusions: Modern information processing methodology and information and communication technology have strongly influenced our societies and health care. As a consequence of this, medical informatics as a discipline has taken a leading role in the further development of health care. This involves developing information systems that enhance opportunities for global access to health services and medical knowledge. Informatics methodology and technology will facilitate high quality of care in aging societies, and will decrease the possibilities of health care errors. It will also enable the dissemination of the latest medical and health information on the web to consumers and health care providers alike. The selected papers of the IMIA Yearbook 2003 present clear examples and future challenges, and they highlight how various sub-disciplines of medical informatics can contribute to this.


2020 ◽  
Vol 6 (1) ◽  
Author(s):  
Johnson K. Murage ◽  
Beatrice K. Amugune ◽  
Peter Njogu ◽  
Stanley Ndwigah

Abstract Background Neglected tropical diseases (NTDs) are a group of communicable diseases which are prevalent in the tropics affecting more than one billion people. Treatment and prevention of these infections is very costly to developing economies. Helminthiases are classified among NTDs. The communities afflicted are poor and have limited access to essential resources for their livelihood. Poor-quality drugs for NTDs may lead to death or prolonged treatment without achieving the desired results. The limited resources used in purchasing poor-quality drugs will therefore be wasted instead of being put to good use. Most of the methods available for the analysis of benzimidazole anthelminthics utilize high-performance liquid chromatography. They are therefore time consuming, require sophisticated and expensive equipment, utilize rare and expensive reagents and solvents, and call for skilled personnel. A simple, rapid, and inexpensive ultraviolet spectrophotometric method of analysis would therefore come in handy especially in the analysis of many samples as occurs during post-authorization market surveillance for quality. Results The suitable solvent for the spectroscopic analysis was established as 0.1 M methanolic HCl. The wavelength of analysis was set at 294 nm. Upon validation, the method was found to have good linearity. The range over which linearity was established was way beyond the 80 to 120% of the working concentration specified by the ICH. The method exhibited good precision. Out of 32 commercial samples analyzed, five (15.6%) did not comply with compendial specifications. Intra-brand batch variation was also observed. Out of three batches of product A002T analyzed, one did not comply with compendial specifications. Conclusion A major limitation in the analysis of benzimidazole anthelminthics is the lack of reliable, simple, rapid, and low-cost methods of analysis with high throughput. The developed method serves to fill this gap. It can be used in the analysis of raw materials and finished products. It can also be used in the establishment of the quality of products prior to registration. The method will prove very useful in post-market surveillance of quality of benzimidazole anthelminthics.


2021 ◽  
Vol 2 (4) ◽  
pp. 1-20
Author(s):  
Ahmed Boubrima ◽  
Edward W. Knightly

In this article, we first investigate the quality of aerial air pollution measurements and characterize the main error sources of drone-mounted gas sensors. To that end, we build ASTRO+, an aerial-ground pollution monitoring platform, and use it to collect a comprehensive dataset of both aerial and reference air pollution measurements. We show that the dynamic airflow caused by drones affects temperature and humidity levels of the ambient air, which then affect the measurement quality of gas sensors. Then, in the second part of this article, we leverage the effects of weather conditions on pollution measurements’ quality in order to design an unmanned aerial vehicle mission planning algorithm that adapts the trajectory of the drones while taking into account the quality of aerial measurements. We evaluate our mission planning approach based on a Volatile Organic Compound pollution dataset and show a high-performance improvement that is maintained even when pollution dynamics are high.


Energies ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4608
Author(s):  
Jingjing He ◽  
Hao Chen ◽  
Xin Su ◽  
Bin Xie ◽  
Quanwei Li

Polyoxymethylene dimethyl ethers (PODE) are a newly appeared promising oxygenated alternative that can greatly reduce soot emissions of diesel engines. The combustion characteristics of the PODE and diesel blends (the blending ratios of PODE are 0%, 20%, 50% and 100% by volume, respectively) are investigated based on an optical engine under the injection timings of 6, 9, 12 and 15-degree crank angles before top dead center and injection pressures of 100 MPa, 120 MPa and 140 MPa in this study. The results show that both the ignition delay and combustion duration of the fuels decrease with the increasing of PODE ratio in the blends. However, in the case of the fuel supply of the optical engine being fixed, the heat release rate, cylinder pressure and temperature of the blend fuels decrease with the PODE addition due to the low lower heating value of PODE. The addition of PODE in diesel can significantly reduce the integrated natural flame luminosity and the soot formation under all injection conditions. When the proportion of the PODE addition is 50% and 100%, the chemical properties of the blends play a leading role in soot formation, while the change of the injection conditions have an inconspicuous effect on it. When the proportion of the PODE addition is 20%, the blend shows excellent characteristics in a comprehensive evaluation of combustion and soot reduction.


Proceedings ◽  
2018 ◽  
Vol 2 (23) ◽  
pp. 1455 ◽  
Author(s):  
Dina Czajczyńska ◽  
Renata Krzyżyńska ◽  
Hussam Jouhara

In 2016 4.94 million tonnes of tyres were produced. Each tyre eventually become waste and pyrolysis has been considered an effective way of utilizing scrap tyres for several decades. However, pyrolysis has failed many times because the process has a great energy demand and the quality of products is unstable or insufficient for commercial use. Usually plants are focused on the production of pyrolytic oil or char and the gaseous phase is only a by-product. In this paper the importance of composition and quality of pyrolytic gas is emphasized. The main chemical properties make this gas a valuable biofuel that may satisfy energy requirements of the whole process (except for the start-up phase). Available data from literature concerning composition and other features of the pyrolytic gas from scrap tyres obtained at temperatures up to 1000 °C are compared with experimental results. The quality of evolved gases is discussed in the context of the Industrial Emissions Directive (IED), too. Finally, an analysis of the mass balances obtained allows a decision about the business profile and profitability.


2016 ◽  
Vol 3 (2) ◽  
pp. 21-34
Author(s):  
Christine Welch ◽  
Tammi Sinha ◽  
Nigel Ward

Operational Excellence (OE) is achieved when high performance teams are seeking for continuous improvement in well-designed processes, using appropriate tools and technologies. Excellence is underpinned by a philosophy in which problem-solving, team-working and effective leadership combine to focus upon customer needs, and all employees are empowered to act to maintain optimal flows of value. OE is clearly a desirable quality of organizations seeking both effectiveness and efficiency in their production of goods and services for customers. OE is underpinned by concepts such as team-working, effective leadership and change management, and depends upon effective flows of value. Systems Thinking (ST) is consequently at the heart of genuine excellence. This paper was conceived in the context of a Community of Practice of business improvement professionals, who took Operational Excellence as their agenda for inquiry during sessions in 2015. Reflection upon practice discussed at these meetings, together with the literature of change management and continuous improvement, have led to development of a systemic ‘landscape' model for pursuit of Operational Excellence. The elements of this model are set out, showing how they can contribute to OE.


Micromachines ◽  
2019 ◽  
Vol 11 (1) ◽  
pp. 13 ◽  
Author(s):  
Bin Zhang ◽  
Jaehyun Lee ◽  
Mincheol Kim ◽  
Naeeung Lee ◽  
Hyungdong Lee ◽  
...  

The macroscopic assembly of two-dimensional materials into a laminar structure has received considerable attention because it improves both the mechanical and chemical properties of the original materials. However, conventional manufacturing methods have certain limitations in that they require a high temperature process, use toxic solvents, and are considerably time consuming. Here, we present a new system for the self-assembly of layer-by-layer (LBL) graphene oxide (GO) via an electrohydrodynamic (EHD) jet printing technique. During printing, the orientation of GO flakes can be controlled by the velocity distribution of liquid jet and electric field-induced alignment spontaneously. Closely-packed GO patterns with an ordered laminar structure can be rapidly realized using an interfacial assembly process on the substrates. The surface roughness and electrical conductivity of the LBL structure were significantly improved compared with conventional dispensing methods. We further applied this technique to fabricate a reduced graphene oxide (r-GO)-based supercapacitor and a three-dimensional (3D) metallic grid hybrid ammonia sensor. We present the EHD-assisted assembly of laminar r-GO structures as a new platform for preparing high-performance energy storage devices and sensors.


2009 ◽  
Author(s):  
Naotoshi Fujita ◽  
Asumi Yamazaki ◽  
Katsuhiro Ichikawa ◽  
Yoshie Kodera

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