A Bayesian Integration of Volumetric and Material Balance Analyses to Quantify Uncertainty in Original Hydrocarbons in Place

Abstract

The authors use a Bayesian formulation to integrate volumetric and material balance analyses. Specifically, they apply Bayes's rule to the Havlena and Odeh material balance equation to estimate original oil in place, N, and relative gas-cap size, m, for a gas-cap drive oil reservoir. The authors consider uncertainty and correlation in the volumetric estimates of N and m, as well as uncertainty in the pressure data. They then quantify uncertainty in the estimates of N and m resulting from the combined volumetric and material balance analyses. By combining the analyses, each reduces the uncertainty of the other, resulting in more accurate in-place estimates than from the separate analyses.     

Remote‐Controlled Hydrogel Depots for Time‐Scheduled Vaccination

Remote‐controlled drug depots represent a highly valuable tool for the timely controlled administration of pharmaceuticals in a patient compliant manner. Here, the first pharmacologically controlled material that allows for the scheduled induction of a medical response in mice is described. To this aim, a novel, humanized biohybrid material that releases its cargo in response to a small‐molecule stimulus licensed for human use is developed. The functionality of the material in mice is demonstrated by the remote‐controlled delivery of a vaccine against the oncogenic human papillomavirus type 16. It is shown that the biohybrid depot‐mediated immunoprotection is equivalent to the classical multi‐injection‐based vaccination. These results indicate that this material can be used as a universal remote‐controlled vehicle for the patient‐compliant delivery of vaccines and pharmaceuticals.     

Self-cleaning wool: effect of noble metals and silica on visible-light-induced functionalities of nano TiO2 colloid

This study intends to enhance the functionality of titanium dioxide (TiO₂) nanoparticles applied to wool fabrics under visible light. Herein, TiO₂, TiO₂/SiO₂, TiO₂/Metal, and TiO₂/Metal/SiO₂ nanocomposite sols were synthesized and applied to wool fabrics through a low-temperature sol–gel method. The impacts of three types of noble metals, namely gold (Au), platinum (Pt), and silver (Ag), on the photoefficiency of TiO₂ and TiO₂/SiO₂ under visible light were studied. Different molar ratios of Metal toTiO₂ (0.01, 0.1, 0.5, and 1%) were employed in synthesizing the sols. Photocatalytic efficiency of fabrics was analyzed through monitoring the removal of red wine stain and degradation of methylene blue under simulated sunlight and visible light, respectively. Also, the antimicrobial activity against Escherichia coli (E. coli) bacterium and the mechanical properties of fabrics were investigated. Through applying binary and ternary nanocomposite sols to fabrics, an enhanced visible-light-induced self-cleaning property was imparted to wool fabrics. It was concluded that the presence of silica and optimized amount of noble metals had a synergistic impact on boosting the photocatalytic and antimicrobial activities of coated samples. The fabrics were further characterized using attenuated total reflectance, energy-dispersive X-ray spectrometry, and scanning electron microscopy images.     

Mechanisms of crack propagation in dry plaster

Controlled crack propagation tests were performed on single edge notched bend samples to investigate the crack growth behaviour of dry plaster. The influence of the relative notch depth on the crack resistance curve has been studied and appears to be very important. The results are discussed considering a qualitative model based on the specific microstructure of plaster and in situ observations of the crack propagation. Two mechanisms acting at different scales and undergoing complex interactions are involved: crack bridging by small gypsum crystals acting locally behind the crack tip and secondary cracking in a macroscopic frontal process zone. Interaction of the main crack with secondary ones undergoes substantial branching and crack accelerations leading to bridging destruction due to sudden crack opening.     

Reducing the PAPR by utilisation of the LDPC code

Peak-to-average power ratio (PAPR) is a major drawback in most multi-carrier communication techniques such as orthogonal frequency division multiplex system (OFDM). OFDM consists of lots of independent modulated subcarriers, as a result the amplitude of such a signal can have very large values. These large peaks increase the amount of intermodulation distortion resulting in an increase in the error rate. The PAPR of an OFDM signal can be reduced in several ways: selective mapping, Golay sequences, cyclic coding, clipping and filtering, and multiple signal representation techniques. The authors have improved the performance of the OFDM system by using low-density parity-check (LDPC) codes as an alternative to turbo coding in mitigating the PAPR problem which has been used in the pervious works of the authors. The authors present the design for the proposed (LDPC) code technique that achieves good error correction performance and is used to lower the PAPR in a multiple-input multiple-output OFDM system. The simulation results show that 6-60- reduction in PAPR over current values in the literature can be achieved depending on the system type.     

Quantifying quantumness of correlations using Gaussian Rényi-2 entropy in optomechanical interfaces

Using the Gaussian Rényi-2 entropy, we analyse the behaviour of two different aspects of quantum correlations (entanglement and quantum discord) in two optomechanical subsystems (optical and mechanical). We work in the resolved sideband and weak coupling regimes. In experimentally accessible parameters, we show that it is possible to create entanglement and quantum discord in the considered subsystems by quantum fluctuations transfer from either light to light or light to matter. We find that both mechanical and optical entanglement are strongly sensitive to thermal noises. In particular, we find that the mechanical one is more affected by thermal effects than that optical. Finally, we reveal that under thermal noises, the discord associated with the entangled state decays aggressively, whereas the discord of the separable state (quantumness of correlations) exhibits a freezing behaviour, seeming to be captured over a wide range of temperature.     

Microstructure and mechanical behavior of die casting AZ91D-Fly ash cenosphere composites

The feasibility of incorporating fly ash cenospheres in die cast magnesium alloy has been demonstrated. The effects of fly ash cenosphere additions on the microstructure and some of the salient physical and mechanical properties of magnesium alloy (AZ91D) metal matrix composites were investigated. The control AZ91D alloy and associated composites, containing 5, 10, and 15 wt.% of fly ash cenospheres (added), were synthesized using a die casting technique. A microstructural comparison showed that microstructural refinement – occurred due to the fly ash additions and became more pronounced with an increase in the percentage of the fly ash added. The metal matrix areas nearer to the fly ash particles exhibited a greater degree of refinement than was observed in the areas further away from these particles. Both filled and unfilled fly ash cenospheres, and porosity were observed in the composite microstructures. The composite specimen densities decreased and the coefficient of thermal expansion did not change significantly as the volume percent of fly ash was increased within the range investigated. The hardness values of the composite specimens exhibited an increase in proportion to the increase in percentage of added fly ash. The tensile strength of the composites also increased as the concentration of fly ash cenospheres was increased. In contrast, the Young’s modulus of these composite samples, as measured by non-destructive pulse-echo method, decreased as the percentage of fly ash in the composite was increased. SEM micrographs of the tensile fracture surfaces showed broken cenospheres on the fracture surface and evidence of ‘pull outs’, where fly ash particles were previously embedded in the matrix. Compression testing results showed that the presence of 5 wt.% cenospheres decreased the compressive strength and compressive yield strength of the composite relative to that of the AZ91D matrix alloy. Surprisingly, a significant change in compression strength was not observed for the composites with 10 and 15 wt.% cenospheres in comparison to the AZ91D matrix alloy. In contrast to the tensile tests, no cenosphere remnants were observed on the compressive test fracture surface of the composites. This observation suggests that the fracture of the composite was initiated within the AZ91D matrix by normal void nucleation and growth, followed by crack propagation through the matrix, avoiding any of the cenospheres, leading to composite fracture of the matrix.     

Epoxide Hydrolase‐Catalysed Kinetic Resolution of a Spiroepoxide,a Key Building Block of Various 11‐Heterosteroids

Two microbial epoxide hydrolases – i.e., Aspergillus niger (AnEH) and Rhodococcus erythropolis (the so‐called “Limonene EH”: LEH) were used to achieve, for the first time, the biocatalysed hydrolytic kinetic resolution (BHKR) of spiroepoxide rac‐ 1 . This compound is a strategic key building block allowing the synthesis of 11‐heterosteroids. Interestingly enough, the two enzymes exhibited opposite and therefore complementary enantioselectivity allowing us to isolate the residual (R,R)‐ 1 (from AnEH) and the residual (S,S)‐ 1 (from LEH) in nearly enantiopure forms (>98 %). Their absolute configurations were determined by X‐ray crystallography. An opposite regioselectivity of the oxirane ring opening for both enantiomers of substrate 1 , determined using H₂¹⁸O labelling and chiral GC‐MS analysis, was also observed, corresponding to an attack at the less substituted carbon atom using AnEH, and at the most substituted carbon atom using LEH. A chemical process‐improving methodology was also developed. This allowed us to obtain both enantiomers of the substrate in high enantiomeric purity (99 %) and optimised quantity. In the case of the AnEH, the use of a biphasic (water/isooctane) reaction medium allowed us to increase the global substrate concentration up to 200 g/ L. The preparation of both enantiomers of 1 clearly paves the way to the preparative scale synthesis and biochemical evaluation of the corresponding 11‐heterosteroid enantiomers.     

Strain energy release rates for a straight-fronted edge crack in a circular bar subject to bending

The strain energy release rate for a straight-fronted edge crack in a bar of circular cross section subjected to pure bending is determined. The cracked bar is modelled with two-dimensional plane-stress finite elements and strain energy release rates, determined from this model, are shown to be in close agreement with existing results for a bar subjected to three-point bending in which strain energy release rates were determined by measuring the compliance of the bar experimentally. The strain energy release rates for a crack in the circular cross section bar are found to be lower than those in a rectangular cross section bar having the same relative crack length and subjected to the same bending moment. Previously determined results for uniform tension are superimposed to obtain strain energy release rates for a circular cross section bar which is subjected simultaneously to a tensile load and a bending moment.