scholarly journals Optimization of Compaction Quality Control in the Core of Random Fillings within Linear Infrastructures: Application to Metamorphic Slate Fillings

2021 ◽  
Vol 13 (19) ◽  
pp. 10957
Author(s):  
Evelio Teijón-López-Zuazo ◽  
Ángel Vega-Zamanillo ◽  
Miguel Ángel Calzada-Pérez ◽  
Luis Juli-Gándara
Keyword(s):  
Quality Control ◽  
Maximum Size ◽  
Test Procedures ◽  
The Core ◽  
High Particle ◽  
Use Of Resources ◽  
Compaction Control ◽  
New Research ◽  
Construction Efficiency

The construction of random fillings from the excavation of medium hardness rocks, with high particle sizes, presents limitations in compaction control. This research applies new control techniques with revised test procedures in the construction of the random fillings core, which constitutes the main part of the embankment, with the bigger volume and provides the geotechnical stability to the infrastructure. The maximum thickness over each of the compacted layers researched that made up the random fillings was 800 mm. As there are many types of rocks, this research is applied to metamorphic slates. Quality control was carried out by applying new research associated with the revision of wheel impression test, topographic settlements, and plate bearing test (PBT). Thus, new test procedures are established, defining efficient thresholds. Comparisons make it possible to choose representative tests, avoiding duplication. The optimization of control reduces inspection times, ensuring quality adapted to the high construction efficiency of diggings. Traditionally, rocks were rejected due to their maximum size, underutilizing the use of high-quality materials. Promoting their utilization implies a better use of resources, and therefore, a higher environmental efficiency. A statistical analysis of the core of 16 slate random fillings was carried out, with a total of 2250 in situ determination of density and moisture content, 75 wheel impression tests, 75 topographic settlement controls, and 75 PBT. The strong associations found between different tests allowed to simplify the quality control.

scholarly journals Modifications for Optimization the Compaction Quality Control in Core Slate Random Filling Embankments for Linear Infrastructures

2021 ◽  
Author(s):  
Evelio Teijón-López-Zuazo ◽  
Ángel Vega-Zamanillo ◽  
Miguel Ángel Calzada-Pérez ◽  
Luis Juli-Gándara
Keyword(s):  
Quality Control ◽  
Particle Sizes ◽  
Test Procedures ◽  
Control Techniques ◽  
High Particle ◽  
Compaction Control ◽  
Geotechnical Stability ◽  
New Research

The construction of random fillings from the excavation of medium hardness rocks, with high particle sizes, presents limitations in compaction control. This research applies new control techniques with revised test procedures in the construction of the random fillings core, which constitutes the main part of the embankment, with the bigger volume and provides the geotechnical stability to the infrastructure. The maximum layer thickness researched was 800mm. As there are many types of rocks, this research is applied to metamorphic slates. Quality control has been carried out by applying new research associated with the revision of wheel impression test, topographic settlements and plate bearing test (PBT). A statistical analysis of the core of 16 slate random fillings has been carried out, with a total of 2250 in situ determination of density and moisture content, 75 wheel impression tests, 75 topographic settlement control and 75 PBT. The strong associations found between different tests have allowed to simplify the quality control.

scholarly journals Modification Tests to Optimize Highway Construction in Crown of Slate Random Embankments with Compaction Quality Control

Materials ◽  
2020 ◽  
Vol 13 (5) ◽  
pp. 1139
Author(s):  
Evelio Teijón-López-Zuazo ◽  
Ángel Vega-Zamanillo ◽  
Miguel Ángel Calzada-Pérez ◽  
Luis Damián Ramos-Pereira
Keyword(s):  
Quality Control ◽  
Laboratory Tests ◽  
Field Work ◽  
Particle Sizes ◽  
Test Procedures ◽  
Crown Area ◽  
Control Procedures ◽  
Compaction Control ◽  
Wheel Tracking

The compaction control of random fills has developed very little due to the limitations of particle sizes, with methods usually using a simple procedural control. In order to develop new quality control procedures for random slate filling, the necessary field work and laboratory tests were carried out. New test procedures for wheel-tracking or settlement tests have been successfully investigated. A total of 4500 in situ measurements of density and 580 topographic settlements, 960 wheel-tracking trolley tests and more than 130 slab rolling tests have been determined. An analysis of variance (ANOVA) has been carried out, obtaining correlations between tests in order to replace the deductibles. The variables that were used to analyze variance were the average lot density, the average settlement between last and first roller pass, the average wheel impression after test carriage, the first vertical modulus of the plate bearing test (PLT), the second vertical modulus of the PLT and the relation between second and first modulus of the PLT. The research proposes a new procedure for the quality control of the compaction of the randomized slate filling used in the crown area.

Imaging of ribosomal RNA-protein interactions by dark-field STEM

1989 ◽  
Vol 47 ◽  
pp. 250-251
Author(s):  
M. Boublik ◽  
V. Mandiyan ◽  
S. Tumminia ◽  
J.F. Hainfeld ◽  
J.S. Wall
Keyword(s):  
Nucleic Acid ◽  
16S Rrna ◽  
Dark Field ◽  
Radius Of Gyration ◽  
Central Domain ◽  
The Core ◽  
16S Rna ◽  
30S Subunit ◽  
Core Particles

Success in protein-free deposition of native nucleic acid molecules from solutions of selected ionic conditions prompted attempts for high resolution imaging of nucleic acid interactions with proteins, not attainable by conventional EM. Since the nucleic acid molecules can be visualized in the dark-field STEM mode without contrasting by heavy atoms, the established linearity between scattering cross-section and molecular weight can be applied to the determination of their molecular mass (M) linear density (M/L), mass distribution and radius of gyration (RG). Determination of these parameters promotes electron microscopic imaging of biological macromolecules by STEM to a quantitative analytical level. This technique is applied to study the mechanism of 16S rRNA folding during the assembly process of the 30S ribosomal subunit of E. coli. The sequential addition of protein S4 which binds to the 5'end of the 16S rRNA and S8 and S15 which bind to the central domain of the molecule leads to a corresponding increase of mass and increased coiling of the 16S rRNA in the core particles. This increased compactness is evident from the decrease in RG values from 114Å to 91Å (in “ribosomal” buffer consisting of 10 mM Hepes pH 7.6, 60 mM KCl, 2 m Mg(OAc)2, 1 mM DTT). The binding of S20, S17 and S7 which interact with the 5'domain, the central domain and the 3'domain, respectively, continues the trend of mass increase. However, the RG values of the core particles exhibit a reverse trend, an increase to 108Å. In addition, the binding of S7 leads to the formation of a globular mass cluster with a diameter of about 115Å and a mass of ∽300 kDa. The rest of the mass, about 330 kDa, remains loosely coiled giving the particle a “medusa-like” appearance. These results provide direct evidence that 16S RNA undergoes significant structural reorganization during the 30S subunit assembly and show that its interactions with the six primary binding proteins are not sufficient for 16S rRNA coiling into particles resembling the native 30S subunit, contrary to what has been reported in the literature.

UV spectroscopic method for determination of phenytoin in bulk and injection forms

2019 ◽  
Author(s):  
Chem Int
Keyword(s):  
Quality Control ◽  
Spectrophotometric Method ◽  
Spectroscopic Method ◽  
Ich Guidelines ◽  
Precision And Accuracy ◽  
Routine Quality Control

Recent study was conducted to develop a simple UV spectrophotometric method to determine Phenytoin in bulk and injection form according to official requirement and validate as per ICH guidelines. λmax of Phenytoin was found 202 nm. Linearity existed perceived in the concentration assortment 2-8 μg/ml (r2 = 0.999) for the method. The method was validated pertaining to linearity, precision and accuracy studies, LOD and LOQ consistent with ICH guidelines. The existent method was establish to be simple, linear, precise, accurate as well as sensitive and can be applied for routine quality control enquiry for the analysis of Phenytoin in bulk and injection form.

Simultaneous Determination of Eight Potential Q-Markers in Zishen Tongguan Capsules Based on UHPLC-MS/MS

2020 ◽  
Vol 17 (1) ◽  
pp. 47-56
Author(s):  
Shun Liu ◽  
Xun Wang ◽  
Kaiping Zou ◽  
Wei Liu ◽  
Cunyu Li ◽  
...  
Keyword(s):  
Quality Control ◽  
Chinese Medicine ◽  
Simultaneous Determination ◽  
High Performance ◽  
Multiple Reaction Monitoring ◽  
Gradient Elution ◽  
Quality Markers ◽  
High Repeatability ◽  
Comprehensive Study

Background: Zishen Tongguan (ZSTG) capsules were prepared at the Affiliated Hospital of Nanjing University of Chinese Medicine and have been proven to be clinically effective for treating pyelonephritis and benign prostatic hyperplasia. However, the quality standards are not ideal; a comprehensive study of the “quality markers” (Q-markers), the chemicals inherent in traditional Chinese medicine and its preparations, has not been carried out. Experimental Methods: In this paper, a sensitive and specific ultra-high-performance liquid chromatographictandem mass spectrometry (UHPLC-MS/MS) method was developed for the simultaneous determination of eight potential Q-markers of ZSTG, including timosaponin A3, berberine, jatrorrhizine, phellodendrine, palmatine, mangiferin, neomangiferin, and timosaponin BII. A Kromasil 100-3.5 C18 column was used with a mobile phase of 0.2% formic acid with acetonitrile, and gradient elution at a flow rate of 0.2 mL/min was achieved in 13 minutes and used for separation. Detection was performed in positive/negative mode with multiple reaction monitoring (MRM). Results: The analytical method was validated in terms of the sensitivity, linearity, accuracy, precision, repeatability, stability and recovery. The method established here was successfully applied to study the potential Q-markers in 8 batches of commercial samples, which demonstrated its use in improving the quality control of ZSTG. Conclusion: The developed method had high repeatability and accuracy and was suitable for the simultaneous analysis of multiple Q-markers, which may provide a new basis for the comprehensive assessment and overall quality control of ZSTG.

Quality Control Optimization Solutions for Determination of Rutin in Supplements Containing Ginkgo Biloba Extract

2016 ◽  
Vol 12 (4) ◽  
pp. 386-390 ◽  
Author(s):  
Ivanka P. Pencheva ◽  
Vania N. Maslarska ◽  
Assena C. Stoimenova ◽  
Manoela M. Manova ◽  
Lily A. Andonova ◽  
...  
Keyword(s):  
Quality Control ◽  
Ginkgo Biloba ◽  
Ginkgo Biloba Extract ◽  
Control Optimization

A Versatile Stability-indicating Liquid Chromatographic Method for the Simultaneous Determination of Atenolol, Hydrochlorothiazide and Chlorthalidone

2020 ◽  
Vol 16 (8) ◽  
pp. 1037-1051
Author(s):  
Ehab Farouk Elkady ◽  
Marwa Ahmed Fouad ◽  
Abdulgabar A. Ezzy Faquih
Keyword(s):  
Quality Control ◽  
Chromatographic Method ◽  
Degradation Products ◽  
Pharmaceutical Dosage Forms ◽  
Potassium Dihydrogen ◽  
Ich Guidelines ◽  
Liquid Chromatographic Method ◽  
Liquid Chromatographic ◽  
Potassium Dihydrogen Orthophosphate

Background: Atenolol is a selective beta 1 blocker that can be used alone or in combination with hydrochlorothiazide or with chlorthalidone for the treatment of hypertension and prevention from a heart attack. Objective: The main target of this work was to improve modern, easy, accurate and selective liquid chromatographic method (RP-HPLC) for the determination of these drugs in the presence of their degradation products. These methods can be used as analytical gadgets in quality control laboratories for a routine examination. Methods: In this method, the separation was accomplished through an Inertsil® ODS-3V C18 column (250 mm x 4.6 mm, 5 μm), the mobile phase used was 25 mM aqueous potassium dihydrogen orthophosphate solution adjusted to pH 6.8 by using 0.1M sodium hydroxide and acetonitrile (77 : 23, v/v), the flow rate used was 1 ml/min and detection was achieved at 235 nm using UV. Results: All peaks were sharp and well separated, the retention times were atenolol degradation (ATN Deg.) 2.311 min, atenolol (ATN) 2.580 min, hydrochlorothiazide degradation (HCT Deg.) 5.890 min, hydrochlorothiazide (HCT) 7.016 min, chlorthalidone degradation CTD Deg 8.018 min and chlorthalidone (CTD) 14.972 min. Linearity was obtained and the range of concentrations was 20- 160 μg/ml for atenolol, 10-80 μg/ml for hydrochlorothiazide and 10-80 μg/ml for chlorthalidone. According to ICH guidelines, method validation was accomplished, these methods include linearity, accuracy, selectivity, precision and robustness. Conclusion: The optimized method demonstrated to be specific, robust and accurate for the quality control of the cited drugs in pharmaceutical dosage forms.

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