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As the development of oil and gas enters a high water cut stage, the formation water environment with high Ca2+ and Cl- poses higher requirements for the safe service of pipe columns. In this work, the influence of Ca2+ concentration and exposure time on the corrosion behavior of 3Cr steel was analyzed by using high temperature autoclave to simulate the downhole flow environment and combining with the electrochemical research results. Research results showed that although the presence of Ca2+ could promote solution acidification, the corrosion rate of 3Cr steel in solutions containing Ca2+ depended more on the quality of the film on the sample surface. When the total Cl- concentration in the solution was 128 000 mg/L and the Ca2+ concentration ranged from 0 to 3 600 mg/L, the maximum average weight loss rate of 2.2 mm/a occurred at the Ca2+ concentration of 1 080 mg/L. Meanwhile, in an environment with a Ca2+ concentration of 180 mg/L, the weight loss rate curve of 3Cr steel showed an inverse “V” trend of weight loss rate over time, and the average weight loss rate of the sample reached the maximum value at the corrosion time of 240 h. When 3Cr steel was immersed in a solution containing Ca2+ with introducing CO2, the FexCa1-xCO3 compounds were formed on the surface of 3Cr steel. In addition, there was no strict ratio between Fe/Ca, and the product states depended on the Ca2+ concentration in the solution.

The article discusses the concept of drip-lines in nuclear physics, which are boundaries beyond which nuclei become unstable and can emit excess protons or neutrons. The focus is on the study of Nitrogen-9 (9N), a five-proton emitter, and its decay process. Experimental results provide evidence for the existence of 9N and its decay pattern, which involves the sequential emission of protons. The findings highlight the importance of understanding open quantum systems and the interplay between nuclear forces and the continuum in shaping nuclear structure and decay mechanisms. [Extracted from the article]

Consequently, when the 2 I p i decay energy I Q i SB 2 I p i sb is comparable with Graph HT ht pp, it is possible for diproton correlation to emerge in the overall energy correlation. The observed momentum correlations among the five particles are consistent with two sequential steps of prompt Graph HT ht decay passing through the ground state of SP 16 sp Ne. This is possibly due to the fact that diproton is a subthreshold resonance [[25]], whose decay width Graph HT ht pp is around 0.9 MeV. Nucleon-Nucleon Correlation Experimentally, the nucleon-nucleon correlations of the 4 Graph HT ht state in SP 22 sp Mg and the ground state (Graph HT ht ) in Graph HT ht Mg have been measured. [Extracted from the article]

With the exploitation of oil and gas resources, the water environment of high-Ca2+ and high-Cl− stratum puts forward high safety requirements for tubular columns. This paper simulates the underground environment by using high-temperature and high-pressure autoclaves, combines electrochemical research results, and analyzes the effect of flow rate on the corrosion behavior of P110 steel in a water environment of 7.5 g/L Ca2+ + 128 g/L Cl− simulated stratum. The research results show that the presence of Ca2+ promotes the acidification of the solution and accelerates the dissolution of P110 steel. With the increased flow rate of the fluid, the corrosion rate of P110 steel increases, but the increasing trend slows down gradually. At the same time, the flow rate decreases the probability of corrosive pitting on P110 steel. The decreasing is closely related the peeling of earlier CaCO3 precipitation by the fluid. [ABSTRACT FROM AUTHOR]

Background: Adequate flap volume is key to maintaining oral function after oral cancer surgery. This study aimed to evaluate changes in radial forearm free flap (RFFF) volumes after 1 year of follow‐up following ablative tumor surgery in the head and neck. Methods: A prospective study that recorded the clinical data of 20 patients with head and neck cancer who underwent RFFF reconstruction. Magnetic resonance (MR) and Mimics Research 19.0 software were used to measure the RFFF volumes at 1, 3, 6, and 12 postoperative months. Results: Compared with one postoperative month, the RFFF volume decreased by 15.5%, 29.4%, and 42.0% at 3, 6, and 12 months, respectively, after surgery. A significant positive correlation between postoperative radiotherapy and RFFF volume changes was detected. Conclusion: The volume of RFFF decreases with time. It is recommended to use overcorrection, with a 40% increase in RFFF volume, to reconstruct head and neck tumor‐related defects. [ABSTRACT FROM AUTHOR]

Background: With the gradual popularity of relatively novel medial sural artery perforator flap (MSAPF), robust studies are needed to compare the surgical outcomes of MSAPF versus multiple free soft flaps (MFSFs) to verify the advantages and disadvantages of MSAPF., Methods: The authors searched PubMed, Web of Science, EMBASE, Cochrane Library, Chinese BioMedical Literature Database (CBM), and China National Knowledge Infrastructure (CNKI) until September, 2020, to identify studies that compared surgical outcomes of MSAPF and MFSFs. Two authors followed the PRISMA guidelines, individually extracted the data and performed the quality assessments. Survival rate of flaps, satisfaction degree of patients in recipient and donor site, skin grafting, and morbidity of recipient and donor site were evaluated., Results: A total of 441 cases from 7 studies were included in our analysis. No significant differences were found regarding survival rate of flaps, recipient morbidity, and recipient satisfaction degree between the 2 groups. However, MSAPF group was significantly superior to MFSFs group in terms of skin grafting, morbidity, and satisfaction degree of donor site., Conclusion: Our meta-analysis showed that the MSPAF and MFSFs groups were similar in terms of survival rate of flaps, recipient morbidity, and recipient satisfaction degree. Medial sural artery perforator flap group was superior to MFSFs group in terms of morbidity and satisfaction degree of donor site. The results may prove that MSAPF is gaining popularity for a reason and is a good choice for repairing soft tissue defects., Competing Interests: The authors report no conflicts of interest., (Copyright © 2020 by Mutaz B. Habal, MD.)