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N-PEGylated-thiazolium salt is used as efficient catalyst for the benzoin condensation. The catalyst was synthesized by reaction of activated polyethylene glycol 10,000 (PEG-10000) with 4-methyl-5-thiazoleethanol (sulfurol). Reaction mixture undergoes temperature-assisted phase transition and catalyst separated by simple filtration. After reaction course, catalyst can be recycled and reused without any apparent loss of activity which makes this process cost effective and hence ecofriendly. Synthesized benzoins and acyloins by this method have been characterized on the basis of melting point and 1H-NMR spectral studies.

Understanding and modelling the wettability of tight rocks is essential for designing fracturing and treatment fluids. In this paper, we measure and analyze spontaneous imbibition of water and oil into five twin core plugs drilled from the cores of a well drilled in the Montney Formation, an unconventional oil and gas play in the Western Canadian Sedimentary Basin. We characterize the samples by measuring the mineralogy using XRD (x-ray diffraction), total organic carbon content, porosity, and permeability. Interestingly, the equilibrated water uptake of the five samples is similar, while, their oil uptake increases by increasing the core porosity and permeability. We define two wetta-bility indices for the oil phase based on the slope and equilibrium values of water and oil imbibition curves. Both indices increase by increasing porosity and permeability, with the slope affinity index showing a stronger correlation. This observation suggests that part of the pore network has a stronger affinity to oil than to water. We also observe that the two indices decrease by increasing neutron porosity and gamma ray parameters measured by wireline logging tools. The samples with higher gamma ray and neutron porosity are expected to have greater clay content, and thus less effective porosity and permeability.

Heart transplantation is one of the most definitive therapies for end-stage heart failure. The therapy is unfortunately marred by the devastating complications of cardiac allograft vasculopathy (CAV). Non-invasive screening and assessment for CAV has been greatly limited by both low sensitivity and poor correlation with adverse outcomes. As such, invasive imaging with coronary angiography has emerged as the gold standard for detection of CAV. Although conventional coronary angiography serves well for larger lesions, the modality has been significantly enhanced with adjunct imaging to visualize the intimal hyperplasia that is a hallmark of the disease process. These modalities include intravascular ultrasound (IVUS) and optical coherence tomography (OCT). In the following review, we summarize both the invasive and non-invasive assessments of CAV. We further conclude that the current evidence poorly supports the use of non-invasive testing for early CAV and that a transition should be considered to routine early angiography with adjunctive intravascular imaging.