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5 and 12 mBq L-1, respectively, were determined by alpha spectrometry. The robustness of the proposed methodology was demonstrated by the determination of polonium ions concentration in various environmental and biological samples and solid certified reference materials.Pulsed neutron logging tool (PNL), particularly small-diameter multifunction PNL, is an essential instrument used in casing well for evaluating residual oil saturation. In a borehole with a multiple casing string structure, PNL tools log in the oil tube and even the space between the casing and oil tube. Borehole/annulus holdup have a significant influence on the evaluation of oil saturation. Hence, the requirement of the estimation of borehole/annulus liquid holdup is highlighted. This study proposes a new method to determine the annulus oil holdup in a casing well with a complex string structure. For this method, the annulus holdup are derived from ΔS, which is defined as the difference between the relative variations of carbon/oxygen and carbon/hydrogen ratios. To demonstrate the feasibility of the proposed method, we first simulate the responses of ΔS under various borehole and formation conditions using the Monte Carlo method. The outcome shows that ΔS covaries with annulus oil holdup, confirming the feasibility of the proposed method in theory. The proposed method is applied to real data measured in an offshore production well. The result confirms that the formation water saturation calculated by the proposed method agrees well with the actual well production status, further confirming that the proposed method has a promising application in residual oil dynamic monitoring.The sum-peak method is a technique for measuring the absolute activity of gamma cascade emitting sources with a single gamma spectrometer. The effects of angular correlations and random coincidences, if not taken into account, can significantly reduce the accuracy of the method. However, we show that Monte Carlo simulations can reproduce the spectral data with a sufficient quality to perform the required corrections. In this work, we introduced a novel approach for data corrections for angular correlations and pile-up using Monte Carlo simulations. Furthermore, the new method for forming the count rate equations leads to a new formula for the sum-peak method, including random coincidences of any order.The various technological advancements in computed tomography (CT) have resulted in remarkable growth in the use of CT imaging in clinical practice, not the least of which has been its establishment as the most valuable imaging examination for the assessment of cardiovascular system disorders. The objective of this study was to assess the effective radiation dose and radiation risk for patients during cardiac CT procedures, based on studies from four different hospitals equipped with 128 slice CT equipment. Thymidine chemical structure A total of eighty-three patients were investigated in this study with different clinical indications. Effective doses were also calculated using software based on Monte Carlo simulation. The mean patient age (years), weight (kg), and body mass index (BMI (kg/m2)) were 49 ± 11, 82 ± 12, and 31 ± 6, respectively. The results of the study revealed that the tube voltage (kVp) and tube current-exposure time product (mAs) ranged between 100 to 140 and 50 to 840 respectively. The overall average patient dose values for the volume CT dose index [(CTDIvol), in mGy)] and dose length product (DLP) (in mGy·cm) were 34.8 ± 15 (3.7-117.0) and 383.8 ± 354 (46.0-3277.0) respectively. The average effective dose (mSv) was 15.2 ± 8 (1.2-61.8). The radiation dose values showed wide variation between different hospitals and even within the same hospital. The results indicate the need to optimize radiation dose and to establish diagnostic reference levels (DRLs) for patients undergoing coronary computed tomography angiography (CCTA), also to harmonize the imaging protocols to ensure reduced radiation risk.On 21 February 1913, a few decades before the International Bureau of Weights and Measures (BIPM) started to develop activities in the field of ionizing radiation, Marie Curie on behalf of the International Radium Commission deposited the first international radium standard at the BIPM in Sèvres. From 1913 to 1935, the international standard was taken out for comparisons at the Curie Laboratory in Paris and returned to the safe at the BIPM. This article describes how the BIPM, established in 1875 by the Metre Convention, was given the role of custodian of the international radium standard at a time when the mission of the BIPM was to maintain the two fundamental units of the Metric System and was mainly directed toward the measurements needed for geodesy, the standardization of the metric system and the establishment of length and mass standards. Through the history of the first and second international radium standards, we can oversee how the mission and role of the BIPM have evolved.Accelerator driven fast nuclear reactors cooled by lead-bismuth eutectic (LBE) are developed for transmuting long-lived radionuclides in spent nuclear fuel. Due to the nature of the coolant, operating the reactor will result in a production of 210Po by neutron capture. Understanding the behavior of this highly radiotoxic nuclide in the event of a failure of the window separating the evacuated proton beam guide from the reactor core is required for safety assessments. The present work aims at acquiring this knowledge by studying the evaporation of polonium from neutron-irradiated LBE and its deposition in a scaled down model of the beam tube. Experimental results along with Monte Carlo simulations indicate that polonium adsorbs as a single species with an adsorption enthalpy of approximately -156 kJ/mol.The effect of microwave heating (MH, 65 and 75 °C for 15, 30, and 60 s) on the bioactive compounds, fatty acid profile, and volatile compounds of orange juice-milk beverage (OJMB) was evaluated during 28 days of refrigerated (4 °C) storage. Conventionally pasteurized (75 °C/15 s) and untreated beverages were used as controls. MH-OJMB presented a lower browning index and higher levels of ascorbic acid, total phenolics, and carotenoids, higher antioxidant activity, and greater α-amylase, α-glucosidase, and ACE inhibitory activity than the pasteurized product, similar to the untreated beverage. No significant differences were observed in the volatile organic compounds and fatty acids levels. Lower temperatures (65 °C) and longer process times (60 s) resulted in higher retention of bioactive compounds. MH can be an alternative to conventional pasteurization for OJMB processing.