Effects of Chemical Composition on the Impact Properties of A533B Steels

2010 ◽  
Vol 654-656 ◽  
pp. 2895-2898
Author(s):  
Byung Jun Kim ◽  
Ryuta Kasada ◽  
Akihiko Kimura
Keyword(s):  
Chemical Composition ◽  
Energy Use ◽  
Test Method ◽  
Test Results ◽  
Shelf Energy ◽  
Intergranular Cracking ◽  
Test Technique ◽  
Physical Mechanisms ◽  
Specimen Test ◽  
The Impact

In order to estimate the long life integrity of vessel steels with considering various material compositions and irradiation conditions, it is necessary to understand physical mechanisms of the degradation of mechanical properties. In this research, chemical composition effects were investigated for Reactor Pressure Vessel Steels (RPVS) to apply small specimen test technique to surveillance test method. All specimens used in this study were machined from the A533B plate material, which are standard, low Mn, high Cu, high P, and high Cu and high P steels. Tensile strength is increased by phosphorous and copper additions. Charpy tests were carried out at temperature from 73 K to 473 K. The ductile to brittle transition temperature (DBTT) is shifted to higher temperatures with phosphorus additions accompanied by the reduction of the upper shelf energy (USE). The fracture mode of P-added A533B steels at temperatures in the lower shelf energy (LSE) region is intergranular cracking. Test results were discussed in view of the differences on elements of Cu, Mn and P.

The Improved Friction Properties of Bonded MoS2 Films by MAO Treating of Al Substrate

2013 ◽  
Vol 275-277 ◽  
pp. 1911-1914 ◽  
Author(s):  
Han Jun Hu ◽  
Hui Zhou ◽  
Yu Gang Zheng ◽  
Kai Feng Zhang ◽  
Zhi Hua Wan
Keyword(s):  
Tribological Properties ◽  
Solid Lubricants ◽  
Ceramic Coatings ◽  
Test System ◽  
Test Method ◽  
Test Results ◽  
Specimen Test ◽  
Micro Arc Oxidation ◽  
A New Technique ◽  
Porous Microstructures

The bonded MoS2 films are widely used as solid lubricants in aerospace mechanisms due to their excellent tribological properties. Traditionally, the MoS2 was directly bonded on the Al substrate that was only treated by the technique named of sandblast. For improving the tribological properties of MoS2 films, micro arc oxidation (MAO) instead of sandblast was introduced as a new technique for treating of Al substrate. In this article, the tribological properties of MoS2 films which were bonded on different surface of Al substrate as mentioned above were discussed, respectively. It was concluded from the test results that the MoS2 films bonded on substrate treated by MAO have better tribological properties than those samples treated by sandblast. The endurance life against abrasion of the former is as high as twenty times of the latter by the stand test method of ball on disk using the UMT Multi-Specimen Test System. This test results could be illustrated by the following reasons. The first is the porous microstructures of MAO ceramic coatings on the Al substrate. The coatings have numerous pits to be good at increasing the binding force with the MoS2 films, and the pits can also provide a MoS2 lubricants reservoir during processes of friction. Both of them improved the MoS2 film’s ability of wear-protective. The second is that hardness of the coating is higher than the Al, and this ensures well wearing resistance, especially in practical application to big load-supporting moving parts, such as bearing, gear, etc…

scholarly journals The influence of chlorine-contaminated fuel on NOx emission control elements in compression engine

2018 ◽  
Vol 19 (6) ◽  
pp. 414-420
Author(s):  
Joanna Faber ◽  
Rafał Sala ◽  
Jarosław Krasowski
Keyword(s):  
Heat Exchanger ◽  
Chemical Composition ◽  
Analytical Methods ◽  
Emission Control ◽  
Engine Fuel ◽  
Test Results ◽  
Main Attention ◽  
Engine Failure ◽  
The Impact

In paper the impact of intentionally chlorine-contaminated fuel on nitrogen oxides emission control elements in compression engine was described. The quality of fuel used is of key importance for the failure-free operation of the engine. Fuel contamination can occur mainly at the transport or storage stage.The main attention was paid to the EGR heat exchanger, which is used for exhaust gases recirculation, being one of the ways to reduce the emission of harmful NOx. The tests were conducted under laboratory conditions (research engine stand tests) in cycles consisting of four phases. The fuel used was intentionally contaminated with chlorine. The test was interrupted after 250 hours at the engine failure and deposits appearance at the EGR heat exchanger. Test results of chemical composition of deposits, analytical methods used and sources and the cause of deposits appearance were described in present paper.

Study on Applicability of Master Curve Methodology Using Miniature C(T) Specimen to a Reactor Pressure Vessel With Low Upper Shelf Energy

2018 ◽  
Author(s):  
Kentaro Yoshimoto ◽  
Takatoshi Hirota ◽  
Hiroyuki Sakamoto ◽  
Masato Oshikiri ◽  
Kazuya Tsutsumi ◽  
...  
Keyword(s):  
Fracture Toughness ◽  
Neutron Irradiation ◽  
Pressure Vessel ◽  
Master Curve ◽  
Energy Use ◽  
Reactor Pressure Vessel ◽  
Test Method ◽  
Shelf Energy ◽  
Irradiation Embrittlement ◽  
Reactor Pressure

Miniature compact tension (Mini-C(T)) specimen can be an effective tool by utilizing together with Master Curve (MC) methodology for fracture toughness evaluation of irradiated reactor pressure vessel (RPV) steels. Recently, Mini-C(T) specimen has been incorporated into the Japanese standard test method related to MC methodology, JEAC4216-2015 and several studies were found focusing on applicability of Mini-C(T) specimen to irradiated RPV materials. However, there exist some other issues to be resolved considering application to irradiated materials. One of them is violation against the limitation criteria for ductile crack growth (DCG) specified in the standards. In general, upper shelf energy (USE) of RPV materials tends to decrease as well as shift in Charpy transition temperature due to neutron irradiation embrittlement. It may cause reduction in resistance of material against DCG and this leads to the problem peculiar to low USE materials such that the limitation for DCG might be dominant rather than that for KJclimit. Therefore, it is possible to fail to obtain valid KJc data even within valid temperature range of MC methodology, i.e. −50°C ≤ T-To ≤ 50°C, for low USE materials using Mini-C(T) specimens. In this study, the RPV steel with USE lower than 68J was made simulating reduction of USE due to neutron irradiation. Fracture toughness tests were performed using Mini-C(T) specimens as well as the standard 1T-C(T) specimens. Based on the test results, the validity for DCG limitation was also evaluated for each datum by post-test observation of fracture surface. Additionally, effectiveness of added side grooves and double thickness of specimen was examined as a countermeasure for Mini-C(T) specimen.

Impact Load Measurements in an Erosive Cavitating Flow

2011 ◽  
Vol 133 (12) ◽  
Author(s):  
Jean-Pierre Franc ◽  
Michel Riondet ◽  
Ayat Karimi ◽  
Georges L. Chahine
Keyword(s):  
Scaling Laws ◽  
Pressure Pulse ◽  
Impact Load ◽  
Pulse Height ◽  
Impact Loads ◽  
Similar Data ◽  
Two Dimensional ◽  
Test Results ◽  
Test Technique ◽  
The Impact

Impact load measurements were carried out in a high-speed cavitation loop by means of a conventional pressure sensor flush-mounted in the region of closure of the cavity where maximum damage was observed. The sensor was dynamically calibrated by the ball drop test technique. Pressure pulse amplitudes were measured at different velocities and constant cavitation number and cavity length. It was found that pressure pulse height spectra follow a simple exponential law, which depends upon two parameters interpreted as a reference peak rate and a reference load. By exploring the dependence of both parameters on flow velocity, it was possible to show that the various histograms measured at different velocities can be reduced to a unique non-dimensional one and derive scaling laws, which enable to transpose results from one velocity to another. The measured values of impact loads are compared to similar data in the literature, and the impact load spectra are discussed with respect to pitting test results available from a previous investigation. It is concluded that an uncertainty remains on the measured values of impact loads and that a special effort should be made to compare quantitatively pitting test results and impact load measurements. To evaluate the coherence of both sets of data with each other, it is suggested to introduce two-dimensional histograms of impact loads by considering the size of the impacted area in addition to the measured impact load amplitude. It is conjectured that the combination of impact load measurements and pitting test measurements should allow the determination of such two-dimensional histograms, which are an essential input for analyzing the material response and computing the progression of erosion with exposure time.

scholarly journals Reductions in Positive Clostridioides difficile Events Reportable to NHSN With Adoption of Reflex EIA Testing in 13 Atlanta Hospitals

2020 ◽  
Vol 41 (S1) ◽  
pp. s47-s48
Author(s):  
Dana Goodenough ◽  
Samantha Sefton ◽  
Elizabeth Smith ◽  
Colleen Kraft ◽  
Jay Varkey ◽  
...  
Keyword(s):  
Population Based ◽  
Performance Measure ◽  
Test Method ◽  
Nucleic Acid Amplification ◽  
Test Results ◽  
Emerging Infections ◽  
Percent Reduction ◽  
Clostridioides Difficile ◽  
Reflex Testing ◽  
The Impact

Background: US hospitals are required to report C. difficile infections (CDIs) to the NHSN as a performance measure tied to payment penalties for poor scores. Currently, only the charted CDI test results performed last in reflex testing scenarios are reported to the NHSN (CDI events). We describe the reduction in NHSN CDI events from the addition of a reflex toxin enzyme immunoassay (EIA) after a positive nucleic acid amplification test (NAAT) in teaching and nonteaching hospitals, and we estimate the impact on standardized infection ratios (SIR). Methods: Reporting of all CDI test results, by test method, occurred during April 2018–July 2019 to the Georgia Emerging Infections program (funded by the Centers for Disease Control and Prevention), which conducts active population-based surveillance in an 8-county Atlanta area (population, 4 million). Among facilities starting reflex EIA testing, results were aggregated by test method during months of reflex testing to calculate facility-specific reduction in NHSN CDI events (% reduction; 1-[no. EIA+/no. NAAT+]). Differences in percent reduction between facilities by characteristic were compared using the Kruskal-Wallis test. We simulated expected changes in the SIR for a range of reductions, assuming equal effect on both community-onset (CO) and hospital-onset (HO) tests. Each facility’s historical NHSN CDI events prior to reflex testing were used to estimate changes to facility-specific SIRs by reducing values by the corresponding facility’s percent reduction. Results: Overall, 13 acute-care hospitals (bed size, 52–633; ICU bed size, 6–105) started reflex testing during the study period (mean, 7 months, 15,800 admissions, 66,400 patient days), resulting in 550 +NAAT tests reflexing to 180 +EIA tests (pooled mean 58% reduction). Percent reduction varied (mean, 67%; range, 42%–81%) but did not differ between larger (≥217 beds) and smaller hospitals (61 vs 50% reduction; P > .05) or by outsourced versus inhouse testing (65% vs 54% reduction; P > .05). Simulations identified a threshold reduction at which point effect on HO counteract the effects on CO events enough to reduce the SIR; thresholds for nonteaching and teaching were 26% and 32% reduction, respectively (Fig. 1). The estimated reductions in facility-specific SIRs using measured percent reductions on historic NHSN CDI events closely paralleled the simulation, and the mean estimated change in SIR was −46% (range, −12% to −71%) (Fig. 1). Conclusions: Although the magnitude of the effect varied, all 13 facilities experienced dramatic reductions in CDI events reportable to NHSN due to reflex testing; applying these reductions to historical NHSN data illustrates anticipated reductions in their facility-specific SIRs due to this testing change.Funding: NoneDisclosures: Scott Fridkin, consulting fee, vaccine industry (various) (spouse)

Model estimates of the results of diabetes patients using modern glucometers with tri-color technology for displaying test results

2019 ◽  
pp. 81-89
Author(s):  
Larisa Dmitrievna Popovich ◽  
Svetlana Valentinovna Svetlichnaya ◽  
Aleksandr Alekseevich Moiseev
Keyword(s):  
Diabetes Mellitus ◽  
Type 2 Diabetes ◽  
Type 1 Diabetes ◽  
Economic Benefits ◽  
Test Results ◽  
Self Monitoring ◽  
Patients With Diabetes ◽  
The Impact

Diabetes – a disease in which the effect of the treatment substantially depends on the patient. Known a study showed that the use of glucometers with the technology of three-color display of test results facilitates self-monitoring of blood sugar and leads to a decrease in glycated hemoglobin (HbAlc). Purpose of the study: to modeling the impact of using of a glucometer with a color-coded display on the clinical outcomes of diabetes mellitus and calculating, the potential economic benefits of reducing the hospitalization rate of patients with diabetes. Material and methods. Based on data from two studies (O. Schnell et al. and M. Baxter et al.) simulation of the reduction in the number of complications with the use of a glucometer with a color indication. In a study by O. Schnell et al. a decrease of HbA1c by 0.69 percent is shown when using the considered type of glucometers, which was the basis of the model. Results. In the model, the use of a glucometer with a color-coded display for type 1 diabetes led to a decrease in the total number of complications by 9.2 thousand over 5 years per a cohort of 40 thousand patients with different initial levels of HbA1c. In a cohort of 40 thousand patients with type 2 diabetes, the simulated number of prevented complications was 1.7 thousand over 5 years. When extrapolating these data to all patients with diabetes included in the federal register of diabetes mellitus (FRD), the number of prevented complications was 55.4 thousand cases for type 1 diabetes and 67.1 thousand cases for type 2 diabetes. The possible economic effect from the use of the device by all patients with a diagnosis of diabetes, which are included in the FRD, estimated at 1.5 billion rubles for a cohort of patients with type 1 diabetes and 5.3 billion rubles for patients with type 2 diabetes. Conclusion. Improving the effectiveness of self-monitoring, which is the result of the use of glucometers with color indicators, can potentially significantly reduce the incidence of complications in diabetes and thereby provide significant economic benefits to society.

Population Study on the Impact Food Chemical Composition on Patients with Non-Alcoholic Fatty Liver Diseases

2018 ◽  
Vol 69 (4) ◽  
pp. 961-964
Author(s):  
Andrei Vasile Olteanu ◽  
Georgiana Emmanuela Gilca Blanariu ◽  
Gheorghe Gh. Balan ◽  
Dana Elena Mitrica ◽  
Elena Gologan ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Fatty Liver ◽  
Nutritional Value ◽  
Liver Steatosis ◽  
Saturated Fat ◽  
Control Group ◽  
Healthy Population ◽  
Alcoholic Fatty Liver ◽  
Major Interest ◽  
The Impact

Non-alcoholic fatty liver disease (NAFLD) has become of major interest worldwide, it is estimated that more than 20% of the general population suffer from liver steatosis. NAFLD is highly associated with metabolic risk factors like type 2 diabetes mellitus, obesity and dyslipidemia, the patients diagnosed with NAFLD should adopt a high fiber low calorie diet, with reduced saturated fat and carbohydrates content, leading to weight loss and improvement of metabolic profile. Our study is aiming to shape the profile of the patient interested in being informed related to food quality and chemical composition and to evaluate the aspects on the food products label which are important for the customer. Between June 2017 and December 2017, 83 patients diagnosed with NASH were included in the study, representing the study group, while 33 subjects, without metabolic syndrome or digestive diseases, selected from patient list belonging to two general practitioners, constituted the control group. Related to the interest of being informed about the chemical composition and nutritional value of the products bought, the study showed a low interest for the provided information on nutritional value. lack of confidence in the provided information and complexity of the information are understandable, the high number of subject reasoning through lack of immediate clinical benefit is surprising. Among the healthy population the willingness to pay attention to this aspect is extremely low.

Chemical Composition and Antimicrobial Activity of Bark and Leaf Extracts of Cupressus sempervirens and Juniperus phoenicea Grown in Al- Jabel Al-Akhdar Region, Libya

2019 ◽  
Vol 9 (4) ◽  
pp. 268-279
Author(s):  
Mohamed E.I. Badawy ◽  
Ibrahim E.A. Kherallah ◽  
Ahmed S.O. Mohareb ◽  
Mohamed. Z.M. Salem ◽  
Hameda A. Yousef
Keyword(s):  
Antimicrobial Activity ◽  
Chemical Composition ◽  
Sea Level ◽  
Plant Extracts ◽  
Complex Mixture ◽  
Biologically Active ◽  
Cupressus Sempervirens ◽  
Leaf Extracts ◽  
Juniperus Phoenicea ◽  
The Impact

Background:Plant extracts are important products in the world and have been widely used for isolation of important biologically active products. Because of their significant environmental impact, extensive research has been explored to determine the antimicrobial activity of plant extracts.Methods:Acetone extracts of the bark and leaf of Cupressus sempervirens and Juniperus phoenicea, collected from three different altitudes (125, 391, and 851 m high of sea level) at Al- Jabel Al-Akhdar area, Libya were obtained and analyzed by GC/MS. The antimicrobial activity of the extracts was further evaluated against plant bacteria Rhizobium radiobacter, Erwinia carotovora, Rhodococcus fascians and Ralstonia solanacearum and fungus Botrytis cinerea.Results:The impact of the altitude from the sea level on the quantity and chemical constituents of the extracts was investigated. The yield was largely dependent on tree species and the highest yield (6.50%) was obtained with C. sempervirens L bark of altitude III (851 m of the sea level), while the lowest (1.17%) was obtained with the leaf extract of C. sempervirens L from altitude I (125 m). The chemical composition analyzed by GC/MS confirmed that the leaf extracts of C. sempervirens and J. phoenicea contained a complex mixture of monoterpene hydrocarbons, sesquiterpenes, diterpenes, diterpenoids, terpenophenolic, steroids and phthalates. However, the bark extracts of both trees contained a mixture of sesquiterpenes, diterpenes, diterpenoids, terpenophenolics, phthalates, retinol and steroids. These constituents revealed some variability among the extracts displaying the highest interesting chemotype of totarol (terpenophenolic) in all extracts (14.63-78.19% of the total extract). The extracts displayed a noteworthy antifungal potency with varying degrees of inhibition of growth with EC50 values ranged from 78.50 to 206.90 mg/L. The extracts obtained from the leaves of C. sempervirens showed that the highest inhibitory activity was obtained with the extract of altitude II (391 m) with MIC 565, 510, 380 and 710 mg/L against E. carotovora, R. fascians, and R. radiobacter and R. solanacearum, respectively.Conclusion:Based on antimicrobial activity, raw plant extracts can be a cost-effective way to protect crops from microbial pathogens. Because plant extracts contain several antimicrobial compounds, the development of resistant pathogens can be delayed.

Open Door System and Endogenous Growth in Indian Economy: An Empirical Analysis on the Role of Human Capital and R&D in Explaining Industrial Productivity

2021 ◽  
Vol 46 (1) ◽  
pp. 24-37
Author(s):  
Arjun K. ◽  
Sanjay Kumar ◽  
A. Sankaran ◽  
Mousumi Das
Keyword(s):  
Human Capital ◽  
Exchange Rate ◽  
Real Exchange Rate ◽  
Endogenous Growth ◽  
Value Added ◽  
Capital Formation ◽  
Knowledge Capital ◽  
Test Technique ◽  
Long Run ◽  
The Impact

The present study investigates the impact of human capital, knowledge capital which is a function of human capital, and real exchange rate scenario in explaining long-run industrial total factor productivity (TFP) from 1980 to 2015 on the theoretical basis of the open endogenous growth model. The variables employed in the contemporary study include manufacturing value added (MNVA) as industrial output measure, gross fixed capital formation (GFCF) as a measure of capital and labour input which is measured using employment data. Gross enrolment ratio (GER) is taken as a measure for human capital formation, expenditure on research and development (R&D) as a proxy for knowledge capital, and real exchange rate indicates global economic shocks. The study involves estimating TFP for Industrial Sector during the post-liberalization period by employing Cobb-Douglas production function. The ARDL bounds test technique for cointegration revealed long-run relation among the varying factors studied. The Toda-Yamamoto causality test concluded bi-directional causality running between, R&D expenditure and Industrial TFP which sends a strong signal to the policymakers for a well-framed long-term integrated approach for human & knowledge capital formation which will act as a strong impetus for manufacturing firms to come up in terms of augmenting production and productivity and expanding foreign market horizon. JEL Classification: D24, E2, J24

Indenter misalignment in impression creep test: Uncertainty, correction and recommendation

2021 ◽  
pp. 030932472199765
Author(s):  
Suo Li ◽  
Dean Deng ◽  
Wei Sun
Keyword(s):  
Creep Test ◽  
Vertical Direction ◽  
Steady State Creep ◽  
Impression Creep ◽  
Finite Element Analyses ◽  
Empirical Formulas ◽  
Test Technique ◽  
Creep Properties ◽  
Miniature Specimen ◽  
Specimen Test

The impression creep test (ICT) method, as a miniature specimen test technique, has been used extensively to determine the in-service creep properties of power plant components. However, the experiment results of the ICT can be affected by some uncertainties associated with the inaccuracies of measurement, which have not been studied before. This paper presents some results of finite element analyses, to evaluate the effect of indenter misalignment on the results of the ICT, such as the steady-state creep deformation rate and the conversion parameters. The results obtained have shown that the angular misalignments of the indenter around horizontal directions have a relatively significant influence on the conversion parameters, and the misalignment around vertical direction has a much less significant effect. Empirical formulas were developed for the possible correction of the conversion factors. Finally, some recommendations on the control of the indenter and specimen alignment were given.

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