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The waterflooding effect evaluation of carbonate fractured–vuggy reservoirs constitutes a comprehensive multiple-information decision-making process involving quantitative unascertained measure theory. This paper establishes a novel comprehensive methodology to evaluate the waterflooding effects of carbonate fractured–vuggy reservoirs for the first time. A new evaluation grading criteria is proposed using the Mahalanobis distance method based on the multi-index comprehensive unascertained measure theory derived from a modified five-scale analytical hierarchy process–entropy weight method. The actual field data from the carbonate fractured–vuggy reservoirs and the nine evaluation indices are specifically applied to demonstrate the calculation process for the construction of the grading system model on the waterflooding effects and to verify the accuracy of the Mahalanobis distance method by comparing the calculation results with the Minkowski and Euclidean distance methods. The proposed methodology facilitates the effective evaluation of the waterflooding strategies implemented in carbonate fractured–vuggy reservoirs with three categories; the ones with outstanding performance usually demonstrated favorable index characteristics, with substantial contributions to the enhanced oil recovery, manifesting with complete well patterns, a balance in the injection–production dynamics, excellent waterflooding utilization, and control competence. In contrast, fractured–vuggy units with fair waterflooding performance revealed limitations in the enhanced oil recovery. It can also be inferred that the mediocre waterflooding performance of the fractured–vuggy units is associated with incomplete well patterns, an imbalance in the injection–production dynamics, low waterflooding utilization, and a negligible waterflooding effect. The results in this study show that this newly proposed integrated model can effectively assess the waterflooding effects quantitatively and provide a more precise scientific basis for evaluating the waterflooding effects in carbonate fractured–vuggy reservoirs, with potential applicability in other fields. [ABSTRACT FROM AUTHOR]

Supercritical CO2 (SC-CO2) scouring and bleaching of flax roves was developed by using enzymes instead of chemical additives. Effect of dosage of enzyme, enzyme ratio, temperature, pressure, time and CO2 flowrate on the scouring and bleaching properties of flax roves was investigated. The results showed that the whiteness and residual gum content were significantly improved under appropriate conditions. Scouring and bleaching of flax roves by SC-CO2 in combination with compound enzymes consisting of cellulose, xylanase and glucose oxidase could increase whiteness and reduce residual gum content. Moreover, glucose oxidase catalyzes the oxidation of β-d-glucose to produce H2O2, leading to the bleaching of fibers. An optimized scouring and bleaching of flax roves in SC-CO2 was recommended at 50 °C and 15 MPa for 60 min with a dosage of enzyme of 3% (% weight of flax roves), an enzyme ratio (in mass) of 1:2:1 (cellulase: xylanase: glucose oxidase) and a CO2 flowrate of 30 g/min. SEM displays more vertical grooves and bulges appeared on the fiber surface. The breaking strength and elongation at break of the samples were improved with the variation of scouring and bleaching conditions in comparison with the original flax roves. [ABSTRACT FROM AUTHOR]

Background: Accurate and early diagnosis of tuberculosis (TB) is of major importance in the control of TB. One of the most important technical advances in diagnosis of tuberculosis is the development of nucleic acid amplification (NAA) tests. However, the choice of the target sequence remains controversial in NAA tests. Recently, interesting alternatives have been found in hypothetical protein coding sequences from mycobacterial genome. Methodology/Principal Findings: To obtain rational biomarker for TB diagnosis, the conservation of three hypothetical genes was firstly evaluated in 714 mycobacterial strains. The results showed that SCAR1 (Sequenced Characterized Amplified Region) based on Rv0264c coding gene showed the highest conservation (99.8%) and SCAR2 based on Rv1508c gene showed the secondary high conservation (99.7%) in M. tuberculosis (MTB) strains. SCAR3 based on Rv2135c gene (3.2%) and IS6110 (8%) showed relatively high deletion rate in MTB strains. Secondly, three SCAR markers were evaluated in 307 clinical sputum from patients in whom TB was suspected or patients with diseases other than TB. The amplification of IS6110 and 16SrRNA sequences together with both clinical and bacteriological identification was as a protocol to evaluate the efficacy of SCAR markers. The sensitivities and specificities, positive predictive value (PPV) and negative predictive value (NPV) of all NAA tests were higher than those of bacteriological detection. In four NAA tests, IS6110 and SCAR3 showed the highest PPV (100%) and low NPV (70% and 68.8%, respectively), and SCAR1 and SCAR2 showed the relatively high PPV and NPV (97% and 82.6%, 95.6% and 88.8%, respectively). Conclusions/Significance: Our result indicated that SCAR1 and SCAR2 with a high degree of sequence conservation represent efficient and promising alternatives as NAA test targets in identification of MTB. Moreover, the targets developed from this study may provide more alternative targets for the development of a multisite system to effectively detect MTB in samples. [ABSTRACT FROM AUTHOR]