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Abstract As island development strategies gain focus for capitalizing deep offshore assets, limitations like fixed slot location bring about the need for drilling extended reach (ERD) wells with multiple drain holes and complex well geometry to maximize the reservoir coverage for increased production. Pressure testing and reservoir fluid sampling operations require long stationary time and pose a risk of differential sticking. Deploying a pressure testing and fluid sampling tool into the drilling bottom-hole assembly (BHA) helps in maintaining well control through continuous circulation and providing measures to retrieve the tool by rotation and jarring in case of pipe sticking. This paper presents the successful deployment of sampling while drilling tools in three ERD wells drilled using water based and oil based muds to acquire representative formation oil samples from a high H2S carbonate reservoir. The formation oil samples were collected immediately after drilling the well to the target depth for limiting the invasion to collect clean samples in shorter pump-out volume and time. After securing the samples, a phase separation test was performed by fluid expansion in a closed chamber to measure the saturation pressure of the oil. A 30-min long pressure build up was also performed for pressure transient analysis to estimate permeability. Formation fluid samples were collected, while pulling out the drilling BHA, within 12-48 hours of drilling the well by pumping out 100-170 liters of fluid from the formation in 4-6 hours. During clean up, absorbance spectroscopy identifies the fluid phases – gas, oil and water. Prominent trends observed in compressibility, mobility, sound slowness and refractive index measurements add confidence to the fluid identification and provide accurate contamination measurements. Single-phase tanks charged with nitrogen were used to assure quality samples for PVT analysis. The sample tanks are made of MP35N alloy and the flow lines are made of titanium that are both H2S resistant and non-scavenging materials and hence, a separate coat of non-scavenging material was not required. In highly deviated wells, sampling while drilling technology can close the gaps of the conventional wireline operation on pipe conveyed logging in addition to saving 5-days of rig time by eliminating the need for conditioning trips, a dedicated run for pressure testing and sampling and minimizing the risk of stuck pipe and well control incidents The results from downhole fluid analysis and PVT lab are compared in this paper. Going forward, this technology can eliminate the requirement of a pilot hole for pressure testing & sampling by enabling sampling in complex well geometries in landing sections and ERD wells. The paper concludes with discussions on suggested improvements in the tool design and capability and recommendations on best practices to align with the lessons learnt in this sampling while drilling campaign.

Abstract The aspects, related to the influence of the electrohydraulic shock method use in a water-cement slurry passing in a closed chamber (activation reactor) with a pre-applied pressure to the system under various processing modes are highlighted in the article. In order to test the effect of this method on water-cement slurry, an installation was developed, consisting of: a high-voltage source, a high-voltage diode, capacitor banks, a closing element and an activation reactor. The necessary experiments were carried out on the completed installation. The procedure for conducting experiments is described in the work, shows a schematic diagram of the installation for performing activation, a diagram of the reactor, and the processing modes. Several activation modes were considered, depending on: the number of pulses (1-4), pulse energy (0.5-8 kJ), water-cement ratio (0.2-0.35), time intervals for starting treatment from the moment the cement was mixed with water (0 -120 minutes), volume and shape of the container (activation reactor), holding temperature (20-60°C), etc. According to the results of the data obtained, it was experimentally established that the use of electric pulse treatment of water-cement suspension has a positive effect on strength (cup compressive strength) indicators, obtained as a result of processing cement stone samples at different times of hardening (1-3 days). The compressive strength of the treated specimens’ increases in comparison with the untreated specimens, increase in strength reaches up to 45%, depending on the activation mode. The resulting effect was achieved due to many factors (high pressure, magnetic, temperature, energy, ultrasonic and other influences), which were applied in the most optimal period of time (stage) of the cement grain hydration process.

Many air pollutants are inhaled by human breathing, increasing the prevalence of respiratory disease and even mortality. With the recent COVID-19 issue, the number of air pollutants affecting humans is demands further investigation. However, there are not many adequate air measuring devices that can cover a variety of air pollutants. In this study, the developed air measurement system is able to measure sixteen air pollutants (PM10, PM2.5, PM4.0, PM1.0, CO2, CH4, temperature, humidity, VOCs, O2, H2S, NH3, SO2, CO, O3, NO2) in real time. The developed ‘multi-item air quality monitoring system’ can measure sixteen air pollutants in real time and transmit them to the server and the smartphone application at the same time. It was developed to reduce air pollutant damage to humans by emergency alerts using the smartphone application. The development system is composed of hardware development (measurement device) and software development (smartphone application, server). To verify the reliability of the developed equipment, a comparative test, temperature–humidity accuracy test, and operating temperature test were conducted. In the comparative test, difference ratios of ±5% for PM10, ±6% for PM2.5, ±4% for O3, ±5% for NO2, ±7% for CO, and ±7% for SO2 were found compared to the professional measuring devices. The temperature and humidity accuracy test result showed high reliability at ±1% and humidity ± 2%. The result of the operating temperature test showed that there was no problem in normal operation, However, further tests including the long-term comparative test and the closed chamber test will be carried out for all sensors. Additional work including a long-term test for more clear reliability of the device and closed chamber accuracy test for all 16-item sensors, data acquisition rate, and data transmit rate are in progress for commercializing the device.

In recent years, much effort has been devoted to understanding the response of plants to various light sources, largely due to advances in industry light-emitting diodes (LEDs). In this study, the effect of different light modes on rocket (Eruca sativa. Mill.) photosynthetic performance and other physiological traits was evaluated using an orthogonal design based on a combination between light intensity, quality, and photoperiod factors. Some morphological and biochemical parameters and photosynthetic efficiency of the plants were analyzed. Plants grew in a closed chamber where three light intensities (160, 190, and 220 μmol m-2 s-1) provided by LEDs with a combination of different ratios of red, green, and blue (R:G:B- 7:0:3, 3:0:7, and 5:2:3) and three different photoperiods (light/dark -10/14 h, 12/12 h, and 14/10 h) were used and compared with white fluorescent light (control). This experimental setup allowed us to study the effect of 9 light modes (LM) compared to white light. The analyzes performed showed that the highest levels of chlorophyll a, chlorophyll b, and carotenoids occurred under LM4, LM3, and LM1, respectively. Chlorophyll a fluorescence measurement showed that the best effective quantum yield of PSII photochemistry Y(II), non-photochemical quenching (NPQ), photochemical quenching coefficient (qP), and electron transport ratio (ETR) were obtained under LM2. The data showed that the application of R7:G0:B3 light mode with a shorter photoperiod than 14/10 h (light/dark), regardless of the light intensity used, resulted in a significant increase in growth as well as higher photosynthetic capacity of rocket plants. Since, a clear correlation between the studied traits under the applied light modes was not found, more features should be studied in future experiments.

In rice paddy, the closed chamber method is broadly used to estimate methane (CH4) emission rate. Since rice plants can significantly affect CH4 production, oxidation and emission, rice plantation inside the chamber is standardized in IPCC guidelines. Methane emission rate is calculated using the increased concentration inside the headspace. Biomass growth might decrease the headspace volume, and thus CH4 emission rates might be overestimated. To evaluate the influence of chamber headspace decreased by rice plant development on CH4 emission rates, five Korean rice cultivars were cultivated in a typical rice paddy, and physical volume changes in rice biomass were assayed using water displacement method. The recommended acrylic closed chambers (H. 1.2 m x W. 0.6 m x L. 0.6 m) were installed, and eight rice plants were transplanted inside the chamber with the same space interval with the outside. Biomass growth significantly decreased the headspace volume of the chamber. However, this volume covered only 0.48–0.55% of the closed chamber volume at the maximum growth stage. During the whole cropping period, mean 0.24–0.28% of chamber headspace was allocated by plant biomass, and thus this level of total CH4 emissions was overestimated. However, this overestimation was much smaller than the errors coming from other investigation processes (i.e., chamber closing hour, temperature recording, inconstant flooding level, different soil environments, etc.) and rice physiological changes. In conclusion, the influence of physical biomass volume inside the closed chamber was negligible to make the error in total CH4 emission assessment in rice paddies.

Compartment syndrome is a painful condition, caused by increased pressure in a closed muscular compartment. A compartment is a group of muscles enclosed in fascia and septa of connective tissue, which separates different muscle groups. The chambers created receive their blood supply through the arteries. As the pressure builds in the closed space, the blood supply to muscles enclosed decreases. Normal compartment pressure allows blood to flow in and then venous outflow to exit the compartment. However, with increased pressure in the compartment, the arterial flow is impaired. Subsequently, venous outflow stops, adding to the volume of the closed chamber, and hence, pressure builds to the point when the arterial flow stops as well. This chapter provides a general overview of the compartment syndrome in orthopaedic surgical practice. It includes definitions, causes, microscopic anatomy and pathophysiology, as well as the management of this condition.

Abstract Background Cannabinoids are increasingly becoming compounds of medical interest. However, cannabis plants only produce carboxylated cannabinoids. In order to access the purported medical benefits of these compounds, the carboxylic acid moiety must be removed. This process is typically performed by heating the plant material or extract; however, cannabinoids being thermolabile can readily degrade, evaporate, or convert to undesired metabolites. Pressurized liquid extraction (PLE) operates using a pseudo-closed system under pressure and temperature. While pressure is maintained at 11 MPa, temperature can be varied from ambient to 200 °C. Methods Temperatures were evaluated (80 to 160 °C) using PLE for the thermo-chemical conversion of cannabinoid acids utilizing water as the solvent in the first step of extraction with subsequent extraction with ethanol. Optimum temperatures were established for the conversion of 6 cannabinoid acids to their neutral cannabinoid forms. Cannabinoid acid conversion was monitored by HPLC. Results The use of PLE for thermo-chemical decarboxylation has resulted in a rapid decarboxylation process taking merely 6 min. The temperatures established here demonstrate statistically significant maxima and minima of cannabinoids and their parent cannabinoid acids. One-way ANOVA analysis shows where individual cannabinoids are statistically different, but the combination of the maxima and minima provides temperatures for optimum thermo-chemical conversion. CBC, CBD, CBDV, and CBG have an optimum temperature of conversion of 140 °C, while THC was 120 °C for 6 min. Discussion Decarboxylation of cannabinoid acids is necessary for conversion to the bioactive neutral form. The pseudo-closed chamber of the PLE makes this an ideal system to rapidly decarboxylate the cannabinoid acids due to pressure and temperature, while minimizing loss typically associated with conventional thermal-decarboxylation. This study established the optimum temperatures for thermo-chemical conversion of the cannabinoid acids in water and provides the groundwork for further development of the technology for industrial scale application.