scholarly journals DEVELOPMENT OF A NATIONAL STANDARD FOR TESTING METHODS FOR SELF-COMPACTING CONCRETE MIXTURE

2021 ◽  
pp. 108-116
Author(s):  
Larisa TITOVA ◽  
Maya BEYLINA ◽  
Vladimir KHLOPUK ◽  
Vladimir SHABALIN
Keyword(s):  
High Performance ◽  
Concrete Mixture ◽  
National Standard ◽  
Regulatory Document ◽  
Testing Methods ◽  
Self Compacting Concrete ◽  
Complex Geometric Shape ◽  
Large Length ◽  
Production Conditions

In world practice, self-compacting concrete is increasingly used due to its unique properties and advantages. Self-compacting concrete mixtures have high ductility, better fluidity, high density with low water content due to the use of special effective mineral and chemical additives that provide high performance for concrete. The rheological properties of SCC differ significantly from those of conventional concrete. In this regard, when designing the composition of concrete and controlling its quality in laboratory and production conditions, several methods for controlling the quality of a self-compacting concrete mixture were created. The purpose of this standard was to create a single regulatory document regulating the assessment of the quality of a self-compacting concrete mixture. Concrete from a self-compacting mixture can be used for underground and hydrotechnical construction for the erection of structures of large length, complex geometric shape and densely reinforced structures.

High-Strength Self-Compacting Concrete and its Application in Shenzhen Mangrove Garden

2013 ◽  
Vol 438-439 ◽  
pp. 338-341
Author(s):  
Xiang Ping Xian ◽  
Wu Jian Long ◽  
Biao Yi Chen ◽  
Min Yi Huang ◽  
Yong Fa Fan
Keyword(s):  
High Performance ◽  
High Performance Concrete ◽  
Raw Materials ◽  
High Strength ◽  
Concrete Mixture ◽  
Flow Properties ◽  
Self Compacting Concrete ◽  
Concrete Mixtures ◽  
Reinforced Steel

Self-compacting concrete (SCC) refers to one kind of high-performance concrete which can fill formwork and condensed reinforced steel by the weight of concrete mixture without vibration. In this investigation, local raw materials from Shenzhen Jinqiang Concrete Co. Ltd were employed. Self-compacting concrete mixtures with targeted 3-day compressive strengths of 60MPa or 80MPa and required flow properties were evaluated. Moreover, the SCC was successfully applied in Shenzhen Mangrove Garden project.

scholarly journals Effect of casting direction on bond of reinforcement in High Performance Self-Compacting Concrete (HPSCC)

2019 ◽  
Vol 262 ◽  
pp. 06004 ◽  
Author(s):  
Piotr Dybeł
Keyword(s):  
Bond Strength ◽  
High Performance ◽  
Bond Stress ◽  
Concrete Mixture ◽  
Experimental Program ◽  
Bond Properties ◽  
Self Compacting Concrete ◽  
Pull Out ◽  
Significant Change ◽  
Bond Characteristics

This paper presents the results of an investigation into the steel-to-concrete bond in high-performance self-compacting concrete (HPSCC) based on direct pull-out tests. Specifically, the effect of the casting direction on bond properties is examined. Two variants of concrete mixture casting were considered in this work: from the top and from the bottom of a mould with a single casting point at one edge. Horizontal specimens with transverse rebars distributed over their heights (480 mm) and lengths (1600 mm) were cast. The experimental program has shown that the direction of concreting plays an important role in the formation of the bond condition. In the case of casting a mixture from the bottom of a mould, in the lower part of a specimen there is no significant change of the bond stress. However, there is a strong improvement in the upper part. The phenomenon observed eliminates the top-bar effect. What is more, for the rebars situated in the upper part of a specimen, improvements in bond characteristics, such as the bond stiffness, bond strength and the effect of the rebar distance from the casting point are all observed in the case of casting a mixture from the bottom of a mould.

Study on Tube Formation Mechanism and Lateral Stiffness Testing Method of the Tubular Conveyor Belt

2014 ◽  
Vol 532 ◽  
pp. 351-355
Author(s):  
Wei Feng Zhang ◽  
Chuan Sheng Wang ◽  
Fu Xia Zhang ◽  
Jia Hong Liu
Keyword(s):  
Conveyor Belt ◽  
Large Error ◽  
Tube Formation ◽  
National Standard ◽  
Lateral Stiffness ◽  
Testing Methods ◽  
Testing Method ◽  
Parameter Measuring ◽  
Unified Method

The tubular conveyor belt is a main part of the conveyor belt industry. The lateral stiffness value is an important parameter measuring the performance of the tubular conveyor belt. Therefore, the lateral stiffness value is an important factor to test the quality of the tubular conveyor belt. Because of the complexity in measuring the tubular conveyor belt, at present, there is no unified method to measure the lateral stiffness of a tubular belt and no unified national standard for the stiffness value, which is the criterion that domestic enterprises lack to guide their production. The paper conducts the research on testing mechanism and testing methods of stiffness value, further demonstrates them by experiments, and solves the problem of poor reproducibility and large error of the stiffness value.

DAYA SAING EKSPOR PRODUK CPO INDONESIA DAN POTENSI HILIRISASI DIOLAH MENJADI BIODIESEL

2020 ◽  
Vol 4 (2) ◽  
Author(s):  
Danar Agus Susanto
Keyword(s):  
Palm Oil ◽  
Comparative Advantage ◽  
Global Market ◽  
National Standard ◽  
Revealed Comparative Advantage ◽  
Crude Palm Oil ◽  
A Value ◽  
World Demand ◽  
Domestic Use

ABSTRACTIndonesia is the world's largest producer of crude palm oil (CPO). Even so, the trend of international trade in Indonesian CPO products has decreased in the last 10 years with a value of -10.19%. The decline in world demand for CPO can be dealt with by utilizing CPO as a biofuel for domestic use, like biodiesel. The purpose of this study is to determine the competitiveness of Indonesian CPO in global trade and determine the parameters of the quality requirements of CPO and biodiesel. The competitiveness analysis method uses the Revealed Comparative Advantage (RCA) method, while the analysis of the potential quality of CPO as a biofuel is carried out by analyzing the Indonesian National Standard (SNI). CPO trade in the global market is controlled by Indonesia with a market share of 50% and Malaysia 25.6%, with the declining trade trend in the last 10 years relatively (2010-2019) of -6.91%. The level of competitiveness of Indonesian CPO products in 2019 is very strong, but on average in the last 10 years, the level of competitiveness of Indonesian CPO is no better than that of Malaysia. Indonesia has SNI 01-2901-2006 and SNI 7182: 2015 as a determinant of the quality of CPO and biodiesel products developed in Indonesia so that the CPO and biodiesel produced fullfil sacurity and safety aspects when used by consumers.Keywords: crude palm oil (CPO), competitivenessv, quality, Indonesian National Standard (SNI) ABSTRAKIndonesia merupakan negara produsen minyak kelapa sawit mentah/ Crude Palm Oil (CPO) terbesar di dunia. Meskipun demikian, tren perdagangan internasional produk CPO Indonesia mengalami penurunan dalam sepuluh tahun terakhir dengan nilai -10,19%. Penurunan permintaan dunia terhadap CPO, dapat disiasati dengan memanfaatkan CPO sebagai bahan bakar nabati untuk keperluan dalam negeri sebagai biodiesel. Tujuan penelitian ini adalah mengetahui daya saing CPO Indonesia dalam perdagangan global dan mengetahui parameter persyaratan mutu CPO dan biodiesel. Metode analisis daya saing menggunakan metode Revealed Comparative Advantage (RCA), sedangkan analisis potensi kualitas CPO sebagai biofuel dilakukan dengan menganalisis Standar Nasional Indoensia (SNI). Perdagangan CPO dalam pasar global dikuasai oleh Indonesia dengan pangsa pasar 50% dan Malaysia 25,6%, dengan tren perdagangan relatif menurun dalam 10 tahun terakhir (2010-2019) sebesar -6,91%. Tingkat daya saing produk CPO Indonesia pada tahun 2019 sangat kuat, namun secara rata-rata dalam 10 tahun terakhir, tingkat daya saing CPO Indonesia tidak lebih baik dari Malaysia. Indonesia memiliki SNI 01-2901-2006 dan SNI 7182:2015 sebagai penentu kualitas produk CPO dan biodiesel yang dikembangkan di Indonesia, sehingga CPO dan biodiesel yang dihasilkan memenuhi aspek keamanan dan keselamatan ketika digunakan oleh konsumen.Kata kunci: crude palm oil (CPO), daya saing, kualitas, Standar Nasional Indonesia (SNI)

DETERMINATION OF QUALITY OF SURFACE IN HOME CONDITIONS

2020 ◽  
Vol 36 (2) ◽  
pp. 93-101
Author(s):  
G.A. Irgalina ◽  
Keyword(s):  
Chemical Reaction ◽  
Regulatory Document ◽  
Organoleptic Evaluation ◽  
Organoleptic Characteristics ◽  
Small Grains ◽  
Sour Cream ◽  
Taste And Smell ◽  
Home Conditions

The article reflects the assessment of the quality of sour cream at home, and considers methods for determining the quality of sour cream. Organoleptic evaluation was performed for compliance with the requirements of GOST 52092-2003 " Smetana. Technical conditions " in terms of appearance, consistency, color, taste and smell. The consistency of sour cream is determined during its mixing, while evaluating the presence of a glossy appearance of sour cream. Sour cream is considered thick if it slowly drains from the whorl. The smell is determined immediately after mixing. Then we evaluate the taste. When evaluating the quality of the samples under study, it was found that the organoleptic characteristics of the samples fully comply with the requirements of the regulatory document. Analyzing the results of the experiment, we can conclude that in the first experiment, the sour cream purchased on the market was completely dissolved, and the sour cream from the store after dissolution showed small grains. And in the second experiment, the results showed that the color did not change in the sample # 2, but under # 1 it turned blue. The basis of this experiment is a qualitative chemical reaction to starch, which is used as a thickener.

Особенности стандартизации химических реагентов для подготовки питьевой воды (на примере коагулянта полиоксихлорида алюминия)

2020 ◽  
Author(s):  
G. Samburskii ◽  
O. Ustinova ◽  
Svetlana, Leont’eva
Keyword(s):  
Organic Contaminants ◽  
Disperse Medium ◽  
Metal Salts ◽  
National Standard ◽  
Process Technology ◽  
Technical Regulation ◽  
Uniform Assessment ◽  
Dissolved Form ◽  
Polyaluminium Chloride

Распространенным технологическим приемом удаления из воды грубодисперсных примесей, находящихся во взвешенном состоянии, а также коллоидных органических загрязнений, присутствующих в растворенном виде, является процесс коагуляции. Эффективными коагулянтами для систем с водной дисперсионной средой являются соли поливалентных металлов. Цель работы заключалась в создании нового государственного стандарта, предназначенного для обеспечения единообразной оценки качества коагулянтов. Рассмотрена область применения коагулянтов в процессе водоподготовки и проведен их сравнительный анализ. Показана необходимость унификации в области процессов контроля качества коагулянтов. Сформулированы общие требования к контролю качества полиоксихлорида алюминия. Представлен разработанный и утвержденный новый национальный стандарт ГОСТ Р 58580-2019 Полиоксихлорид алюминия. Технические условия , который учитывает требования санитарного законодательства, технического регулирования, безопасности процессов производства и транспортировки полиоксихлорида алюминия.Coagulation process has been a widespread process technology for removing coarse suspended impurities from water, as well as colloidal organic contaminants present in dissolved form. Polyvalent metal salts are effective coagulants for the systems with aqueous disperse medium. The purpose of the work was developing a new state standard to provide for a uniform assessment of the quality of coagulants. The scope of coagulants in the process of water treatment is considered and their comparative analysis is carried out. The general requirements to the control of polyaluminium chloride quality are formulated. The developed and approved new national standard GOST R 58580-2019 Polyaluminium chloride. Technical conditions is presented that takes into account the requirements of sanitary legislation, technical regulation, safety of the processes of production and transportation of polyaluminium chloride.

THE EFFECT OF PROCESSING METHODS ON THE NUTRITIONAL QUALITY OF AFRICAN BREADFRUITS (TRECULIA AFRICANA) SEEDS

2020 ◽  
Vol 16 (2) ◽  
pp. 60
Author(s):  
Nwozo Sarah Onyenibe ◽  
Julius Oluwaseun Oluwafunmilola ◽  
Stanley Udogadi Nwawuba
Keyword(s):  
Amino Acid ◽  
Amino Acid Composition ◽  
Acid Composition ◽  
Nutritional Quality ◽  
High Performance ◽  
Phytochemical Analysis ◽  
Mineral Contents ◽  
Processing Methods ◽  
African Breadfruit

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.

scholarly journals Development and application of a spectrophotometric method in quality evaluation of benzimidazole anthelminthics in Nairobi city county

2020 ◽  
Vol 6 (1) ◽  
Author(s):  
Johnson K. Murage ◽  
Beatrice K. Amugune ◽  
Peter Njogu ◽  
Stanley Ndwigah
Keyword(s):  
Spectrophotometric Method ◽  
High Performance ◽  
Neglected Tropical Diseases ◽  
Developing Economies ◽  
Raw Materials ◽  
Poor Quality ◽  
Prolonged Treatment ◽  
Good Precision ◽  
Market Surveillance

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.

Robust Environmental Sensing Using UAVs

2021 ◽  
Vol 2 (4) ◽  
pp. 1-20
Author(s):  
Ahmed Boubrima ◽  
Edward W. Knightly
Keyword(s):  
Air Pollution ◽  
Gas Sensors ◽  
High Performance ◽  
Weather Conditions ◽  
Ambient Air ◽  
Mission Planning ◽  
Pollution Monitoring ◽  
Compound Pollution ◽  
Planning Algorithm

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.

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