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Petroleum-based drilling cuttings (PBDCs), as hazardous waste, are characterized by high petroleum pollutant contents and complex compositions and must be properly treated. Their treatment by a hammermill thermal desorption system can generate a variety of products, necessitating better delineation of the transformation characteristics of organic matter at the molecular level. In this study, the transformation characteristics of organic matter in the treatment of PBDCs by a hammermill thermal desorption system have been analyzed by positive-ion atmospheric-pressure photo-ionization Fourier-transform ion cyclotron resonance mass spectrometry (+APPI FT-ICR MS). The results showed that the PBDCs contained large amounts of CH, CHO, and CHON compounds and a small amount of CHS compounds. Of these, CH and CHO compounds are easily separated and recovered by the hammermill thermal desorption treatment system. Most of this organic matter is separated directly through physical changes, whereas only 0.32% undergoes chemical reactions. The organic matter in the recovered petroleum and #110 industrial white oil was highly reproducible and similar in terms of saturation and aromaticity. The mineral composition of the PBDCs did not change significantly during treatment by the hammermill thermal desorption system. This research may provide theoretical guidance for the efficient treatment of PBDCs by the hammermill thermal desorption system. [ABSTRACT FROM AUTHOR]

Oil-based cuttings (OBCs) produced by shale gas exploitation are classified as hazardous waste. Their appropriate utilization and disposal is a key issue that urgently needs to be resolved. A single-phase microemulsion (SPM) has ultra-low interfacial tension and strong solubilization ability. In view of this, based on an analysis of the characteristics of OBCs, SPMs have been selected for their cleaning. The effects of microemulsion components and other conditions on the cleaning efficacy have been explored, as well as the deoiling mechanism and the recycling efficiency of the SPM. Our results have shown that sodium dodecylbenzene sulfonate (SDBS), n-butanol, water, and white oil in appropriate proportions can form an effective SPM. The oil content (OC) of OBCs after cleaning was reduced from 11.89% (±0.32%) to 1.13% (±0.02%) when the proportions of the aforementioned components of the SPM were 14.3%, 14.3%, 66.6%, and 4.8%, respectively. The OC of the residue further decreased to 0.28% (±0.05%) after a second cleaning with an alkaline solution. The optimum SPM conditions for cleaning OBCs were identified as a stirring speed of 200 rpm, a temperature of 30 °C, a cleaning time of 30 min, and a solid to liquid mass to volume ratio of 1:4. The main mechanism whereby the SPM cleans the OBCs is that the former reduces the combined work and adhesion work required for the removal of oil droplets from the cuttings, so that the adhesive oil is easily gathered up. Furthermore, the gathered oil phase is solubilized by the SPM. [ABSTRACT FROM AUTHOR]

To achieve a uniform water distribution and to promote the stabilization of bioreactor landfills, the effects of different density on the transport and hydraulic characteristics of recirculated leachate were studied in a Li+ tracer experiment. The landfill density was related negatively to the maximum production rate of leachate, the percentage of Li+ tracer solution and the cumulative amount of Li+ that washed out in the first recirculation round. The cumulative amount of Li+ that was washed out accounted for 92.61%, 82.07% and 75.25% of the injection volume in three waste columns (1#, 2# and 3#) with landfill densities of 497.5, 726.4 and 970.1 kg m−3 at the thirtieth recirculation, respectively. The results revealed that a greater landfill density yielded a smaller amount of Li+ that was washed out per recirculation cycle and the cumulative amount of Li+ washed out, and a longer contact time between the waste and leachate. Moreover, waste columns 1#, 2# and 3# are reactors with a high dispersion and obvious retention zones, and their Morrill Dispersion Index (MDI) values were 25.00, 34.51 and 24.55, respectively. A short-flow phenomenon is obvious in the reactor with a low landfill density. Furthermore, the plug-flow effect is relatively better in the reactor with a high landfill density. To achieve a uniform distribution of recirculated leachate in the landfill, the MDI of the reactor should be reduced combined with other measures, such as pre-crushing and different recirculation schemes. [ABSTRACT FROM AUTHOR]

Background: Breast cancer, as one of the most common malignancies among women globally, presents a concerning incidence rate, underscoring the importance of addressing the treatment of its precursor lesion, ductal carcinoma in situ (DCIS). Treatment decisions for DCIS, involving the balance between breast-conserving surgery (BCS) and mastectomy, remain an area requiring further investigation. This study aimed to compare influence of different surgical types on overall survival (OS) of patients with DCIS and identify specific subgroups with improved OS to develop an effective survival nomogram for patients., Methods: Patient data from the Surveillance, Epidemiology, and End Results (SEER) database for DCIS cohort from 2010 to 2020 were retrieved. Kaplan-Meier (K-M) survival curves were utilized to compare prognostic OS of patients with different surgical methods. Cox regression analysis was employed to determine prognostic factors and establish a nomogram to predict 3-, 5-, and 10-year survival rates. The model was confirmed by Concordance Index (C-index), calibration curves, and receiver operating characteristic (ROC) curves., Results: A total of 71,675 patients with DCIS were included. Patients who underwent subcutaneous mastectomy (SM) demonstrated the best OS compared to other surgical types. Additionally, adjuvant radiotherapy or chemotherapy in combination with surgery significantly improved OS compared to surgery alone. Among DCIS patients aged ≤74 years, those who underwent SM benefited the most in terms of OS, while in the age group of 63-74 years, patients who underwent BCS had significantly higher OS than those who underwent total (simple) mastectomy (TM)/modified radical mastectomy (MRM). Multiple factors were associated with improved OS in DCIS patients, and these factors were integrated into the nomogram to establish OS predictions. The C-index, calibration curves, and ROC curves indicated that the nomogram was suitable for assessing patient prognosis., Conclusions: This study demonstrated that SM treatment yielded the best survival rates for DCIS patients, providing important guidance for future surgical decision-making. Moreover, identifying multiple independent factors related to survival and establishing reliable survival nomograms can assist physicians in developing personalized treatment plans and prolonging patient survival., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://gs.amegroups.com/article/view/10.21037/gs-23-468/coif). The authors have no conflicts of interest to declare., (2024 Gland Surgery. All rights reserved.)