Non-flow Conditions Research Articles

Sensitivity analysis for enhancing crude oil recovery with continuous flow gas lift: A study in reference to the porous media of the upper Assam basin, India

Despite minimal formation damage or water-cut, the majority of oil wells in brown oil fields cease to flow naturally. The current study looks into and analyses what caused a self-flowing well in the upper Assam basin to become non-flowing. The non-flow condition of the well was investigated in the current work as a function of water cut, reservoir pressure, reservoir rock permeability, and GOR. The effect of WHP and WHT on these functions was investigated. This work incorporates innovative methodology that uses the PROSPER simulation model for assessing the possibility of establishing flowability in a dead well based on inflow (IPR) and vertical lift performance (VLP). Subsequent analysis was carried out to examine the scope of producing this dead well under continuous flow gas lift. For this, the current work first examined the tubing diameter and reservoir temperature as standalone parameters to find out if they have any role to play in the flowability of the dead well. Following this, sensitivity analysis was done taking four parameters into account, i.e., reservoir pressure, reservoir rock permeability, water cut, and total GOR. In the current work, surface equipment correlation was established using Beggs and Brill correlation, while vertical lift performance was established using correlation from Petroleum Expert. The results of the current work highlight that a well's production rate under continuous flow gas lift can be enhanced by employing an optimised gas injection rate. The findings of this work conclude that higher reservoir pressure enables an oil well to produce with a high water cut under a continuous flow gas lift system, provided there are no formation damage issues on the well.

Analysis of the flow mixing and energy separation in a Ranque–Hilsch vortex tube based on an area ratio study

Ranque-Hilsch vortex tube is a pressure-driven thermal device that is an essential component of waste pressure utilization, especially in gas industry. However, the lack of an effective optimization design method and relative low efficiency restrict its development. In this study, the flow field and energy separation of five area ratios (AR) from 0.02–0.32 with the same inlet areas were analyzed based on the AR study of a vortex tube through experiments and numerical simulation. To determine the correlation of area ratio and energy separation, the basic flow field distributions are obtained and the flow structure is analyzed. The results show that for the fifth tube, denoted by AR5, the inlet mass flowrate remains largely constant (min = 9.27–9.24 g/s) with extremely small changes in the back pressure at hot exit (Ph = 11.2–18 kPa); in contrast, for AR1, the back pressure at hot exit (Ph = 10–148 kPa) and inlet mass flowrate (min = 6.8–4.26 g/s) vary significantly with increasing cold mass fraction. Moreover, despite using the same moderate cold orifice ratio of 0.48 for all the five tubes, back flow can occur at the cold exit even at an extremely large cold mass fraction of 0.82 for AR5. In addition, various flow structures and mixing and their corresponding causes inside the vortex tube are summarized. The comparison of the flow and thermal behaviors under the five ARs reveals opposite working patterns of reverse flow boundary and off-optimization under the non-flow mixing condition. These conflicting working patterns of reverse flow boundary can be attributed to the multi-parameter interaction of vortex tube. Thus, the criteria for tube optimization may unilaterally fail unless the precession frequency is studied. Finally, a performance evaluation index that quantifies the energy separation performance is proposed. The index serves to improve the tube optimization criteria and further develop the optimization of vortex tubes.

Different modeling approaches in the simulation of extrinsic coagulation factor X activation: Limitations and areas of applicability.

Proteolytic reactions on the phospholipid membrane surface, so-called "membrane-dependent" reactions, play central role in the process of blood clotting. One particularly important example is FX activation by the extrinsic tenase (VIIa/TF). Here we constructed three mathematical models of FX activation by VIIa/TF: (A) a homogeneous "well-mixed" model, (B) a two-compartment "well-mixed" model, (C) a heterogeneous model with diffusion, to investigate the impact and importance of inclusion of each complexity level. All models provided good description of the reported experimental data and were equivalently applicable for <40 μM of phospholipids. Model C provided better predictions than A, B in the presence of TF-negative phospholipid microparticles. Models predicted that for high TF surface density (STF ) and FX deficiency the FX activation rate was limited by the rate of FX binding to the membrane. For low STF and excess of FX the reaction rate was limited by the tenase formation rate. The analysis of the substrate delivery pathways revealed that FX bound to VIIa/TF predominantly from solution for STF >2.8 × 10-3 nmol/cm2 and from the membrane for lower STF . We proposed the experimental setting to distinguish between the collision-limited and non-collision-limited binding. The analysis of models in flow and non-flow conditions revealed that the model of a vesicle in flow might be substituted by model C in the absence of the substrate depletion. Together, this study was the first which provided the direct comparison of more simple and more complex models. The reaction mechanisms were studied in a wide range of conditions.

Effects of intermittent flow on biofilms are driven by stream characteristics rather than history of intermittency

Intermittent streams are found all over the world, however most studies focus on intermittency in hot, arid climates. As flow intermittency is expected to increase with climate change, it is important to understand how stream biofilms in temperate regions respond to these changing conditions. In this study, 20 different streams from around Austria were sampled under flowing and non-flowing conditions to evaluate the effect of intermittency on temperate stream biofilms. These streams encompassed two distinct stream types: fine-grained with high agricultural land use and coarse sediments from relatively pristine areas. Half of these streams were historically intermittent and half historically perennial. Samples were taken from all streams during the spring and fall, when the intermittent streams were flowing and dry, respectively. Subsets of the sediments were subjected to controlled drying to evaluate the effects of history of intermittency on the biofilms. Samples were analyzed for respiration, extracellular enzyme activities, and extracellular polysaccharides in the wet and dry sediments from the field, as well as the lab-dried sediments. This study found that lab-dried perennial sediments showed similar responses to the intermittent sediments, indicating that history of intermittency does not affect biofilm response to drought. This study also found that the effects of grain size, seasonal growth, and nutrient levels have a larger impact on the biofilms than moisture content and history of intermittency.

Study of the pore space heterogeneity effect on the absolute permeability tensors calculated under different boundary conditions and driving forces using a “Computational Rock Physics” technology

In this paper, we study the effect of pore space heterogeneity on off-diagonal permeability tensors calculated for four possible combinations between external boundary conditions (non-flow and periodic) and the driving force inducing the fluid flow (pressure drop and body force). The results were obtained using “Computational Rock Physics” technology, which involves numerical experiments in digital models of porous media. As a mathematical model describing a single-phase flow in porous media, the lattice Boltzmann equations in combination with the multi-relaxation time scheme are used. Porous structures with various heterogeneities are generated using a combination of the Monte-Carlo movement algorithm and the Quartet Structure Generation Set method. The results show that for non-flow boundary conditions (BC), the diagonal components calculated for the body force exceed the corresponding values calculated for the pressure drop, but for the periodic BC, the opposite trend was revealed. It has been established that the heterogeneity significantly affects the sensitivity of the permeability components to the type of driving force as follows: an increase in heterogeneity promotes an increase in differences between the permeability components calculated under pressure drop and body force. The sensitivity of the diagonal components to the driving force is higher in the case of non-flow BC. The paper also considers the issue of the asymmetry of the permeability tensor and the influence of heterogeneity, types of boundary conditions, and driving forces on it. It was found that the permeability tensor is absolutely symmetrical only for periodic BC and body force, while for the other three combinations this is not the case. The power of tensor asymmetry increases with increasing pore space heterogeneity. Differences in the permeability components, as well as the power of tensor asymmetry, decrease with the increasing scale of the sample.

Single-Cell RNA Sequencing Reveals Endothelial Cell Transcriptome Heterogeneity Under Homeostatic Laminar Flow.

Objective: Endothelial cells (ECs) that form the innermost layer of all vessels exhibit heterogeneous cell behaviors and responses to pro-angiogenic signals that are critical for vascular sprouting and angiogenesis. Once vessels form, remodeling and blood flow lead to EC quiescence, and homogeneity in cell behaviors and signaling responses. These changes are important for the function of mature vessels, but whether and at what level ECs regulate overall expression heterogeneity during this transition is poorly understood. Here, we profiled EC transcriptomic heterogeneity, and expression heterogeneity of selected proteins, under homeostatic laminar flow. Approach and Results: Single-cell RNA sequencing and fluorescence microscopy were used to characterize heterogeneity in RNA and protein gene expression levels of human ECs under homeostatic laminar flow compared to nonflow conditions. Analysis of transcriptome variance, Gini coefficient, and coefficient of variation showed that more genes increased RNA heterogeneity under laminar flow relative to genes whose expression became more homogeneous, although small subsets of cells did not follow this pattern. Analysis of a subset of genes for relative protein expression revealed little congruence between RNA and protein heterogeneity changes under flow. In contrast, the magnitude of expression level changes in RNA and protein was more coordinated among ECs in flow versus nonflow conditions. Conclusions: ECs exposed to homeostatic laminar flow showed overall increased heterogeneity in RNA expression levels, while expression heterogeneity of selected cognate proteins did not follow RNA heterogeneity changes closely. These findings suggest that EC homeostasis is imposed post-transcriptionally in response to laminar flow.

Контроль концентрации минерального азота как возможного фактора влияния на результаты вальвометрии мидий, содержащихся в непроточных условиях при недостатке пищи

We investigated changes in the content of mineral forms of nitrogen formed as a result of mussel vital activity in non-flow conditions under favorable temperature and aeration, but with food deficiency, as a possible factor influencing mussel flap movement and valvometry results. A laboratory 11-day experiment was carried out with mussels 24–26 mm long. The dry weight of their soft tissues was about 35 mg. The experiment consisted of five exposures lasting 17-67 h. The mussels were kept in 3-liter vessels with 3 individuals in each, feeding only on the natural food available in this volume of water. In parallel, vessels with aerated water without mussels in them were exposed. Ammonium, nitrite, and nitrate concentrations were measured at the beginning (i.e., in fresh seawater from the Sevastopol coastal zone) and at the end of each exposure. It was determined that, compared to the initial level at the end of the exposures, on average, the content of ammonium in vessels with mussels increased by 250%, nitrite – by 25%, and nitrate – did not change. In vessels without mussels, the content of ammonium, on average, decreased by 250 %, changes in the level of nitrite and nitrate corresponded to changes in the concentration of these nitrogen forms in vessels with mussels. The greatest variability was characteristic of the final values of ammonium concentration, in some exposures it could increase by 700 %. However, the maximum value of ammonium content during the experiment reached only 21, 7 μg N/l, which is two orders of magnitude lower than its MPC level for marine fishery objects. It follows from the obtained data that in experiments with mussels kept in non-flow conditions with food deficiency, the probability of the effect of ammonium excreted by them, as well as of products of its further biological oxidation on valvometry results is not high.

Development of a dynamic analytical model for estimating waste heat from domestic hot water systems

Domestic Hot Water (DHW) production accounts on average between 14 14% and 30% of the residential energy consumption worldwide. In UK dewllings, a quarter of the energy is consumed to produce hot water and this proportion is likely to increase as the energy required for space heating reduces over time in order to achieve demand reduction targets. As the margins for improving the performance of heating system technologies increase, the need for improving modelling accuracy and precision increases also. Although studies have considered DHW use in buildings, there is a lack of reflection on the energy loss and performance of systems in contemporary dwellings. Current simulation tools with simplified assumptions, limited variables and algorithm detail, might lead to unreliable results in terms of the estimated heat losses. In this research, an analytical dynamic model has been developed to estimate heat loss from a domestic hot water system based on high resolution monitored data for a set of dwellings in the UK. The model estimated heat losses during flowing and non-flowing (cooling down) conditions in the distribution system as well as heat losses from the storage tank. It was found that apart from the significant heat loss from the storage tank, short draw-offs are particularly influential in determining the amount of heat wasted. Considerable savings might be achieved ‘avoiding’ short draw-offs through a better control of the system and/or changes in the user behaviour. Insulating and reducing the effective length of the distribution pipe network through better design of the system similarly predict significant reductions in heat losses.

Icing - Renewable Water Source and Resource

The icing phenomena occurs in Mongolia every winter, same places where groundwater overflow on ice on surface waterbed, create next ice sheet and create extended ice storage. This phenomenon is important parameters in hydrological cycle and surface water regime for semi-arid, cold regions. The highly continental, semi-arid and cold region has a high variability in river discharge depending on precipitation, with a general tendency towards decreasing water availability due to increasing air temperatures and thus rising potential evaporation. In this study considered understanding natural process of creating icing, due to keep water source as in ice form on surface in dry season. From March to May icing meltwater recharge groundwater and river flow while river is non-flow condition. Some year’s in April riverbed dry without ice in valley under highly mountains, but upper side is cold and water source is still in snow and ice form. Therefore, icing in river valley could recharge surface water by melting where is cold on top mountains river origin but under valley riverbed no snow, ice cover. In this paper written icing process code by MATLAB using energy change between water, air and ice. When we are promoting naturally ice storing or build icing then winter coldness creates ice storage thus artificially recharge surface water resources in dry season like April. The ice storage amount and simulation results shown that recharge groundwater in dry season is icing method one of the possibilities which creates and build huge ice storages in winter. That is new technology keep water in ice form through winter and recharge surface and groundwater in dry season.

Duration of water flow interruption drives the structure and functional diversity of stream benthic diatoms

Flow cessation affects river ecosystems submitted to low precipitation and increased water demand, and creates unfavourable conditions to aquatic biological communities. Diatoms are amongst the most sensitive biological groups to hydric stress, making them good indicators of preceding hydrological conditions. We here analyse the response of diatom assemblages to the duration and frequency of non-flow periods in 23 Mediterranean temporary streams. All of them experienced a strong decrease in water flow during summer, leading to a period of flow cessation. In addition, other ten permanent streams (zero dry days during the study period) were included in the study for comparative purposes. Temporary and permanent streams showed similar diatom species richness, evenness, and alpha diversity. However, beta diversity was higher in temporary than permanent streams, regardless rare taxa (<1% occurrence) had similar numbers in the two types of streams. Alpha diversity, richness, and evenness of diatom assemblages in the temporary streams changed with the duration of the non-flow period. Durations of 50–100 days were associated to higher alpha diversity, richness, and evenness, but longer non-flow periods caused their decrease. Diatoms thriving under the most extreme conditions were mostly aerophilic, pioneer, and motile taxa. The proportion of aerophilic diatom taxa increased beyond 100 dry days, particularly in those sites receiving more intense solar radiation. Overall, the taxonomical and functional composition of diatom assemblages mostly responded to the duration of the non-flow period, irrespectively of these being consecutive or not. This study shows that diatom assemblages from temporary streams contain taxa adapted to non-flow conditions, but remain vulnerable to further reductions of water flow associated to climate or global change. ‘Unimpacted’ watercourses in the Mediterranean region, independently of their flow regime, should be urgently protected and used as taxonomical and functional early indicators of climate change.

КОЛИВАННЯ ЕЛЕМЕНТІВ КОНСТРУКЦІЙ ПІД ДІЄЮ ПЕРІОДИЧНИХ НАВАНТАЖЕНЬ З УРАХУВАННЯМ ЕФЕКТІВ ГІДРОПРУЖНОСТІ

Значна частина сучасного енергетичного обладнання працює в умовах взаємодії з оточуючим середовищем. Високі швидкості рідини спричиняють появу суттєвого тиску на поверхні конструктивних елементів. В свою чергу, коливання елементів машин та споруд в потоці рідини веде до зміни параметрів руху рідини. Тобто виникає зв’язана задача визначення міцнісних та динамічних характеристик таких систем. З одного боку коливання пружного тіла змінюють параметри течії, а з іншого саме наявність течії призводить до суттєвого впливу на динамічні характеристики конструкції. З точки зору механіки, такі задачі можна класифікувати як задачі взаємодії різних суцільних середовищ. Для опису руху суцільних середовищ використовують загальні рівняння руху, рівняння стану, закони збереження. Різні суцільні середовища відрізняються різним зв’язком між компонентами тензорів напружень та тензорів деформацій або швидкостей деформацій. За допомогою методу зважених нев’язок в роботі отримані основні співвідношення для визначення узагальнених переміщень. При цьому загальне формулювання передбачає можливість визначення частот та форм власних коливань конструкції без врахування приєднаних мас рідини, з їх урахуванням, а також досліджувати вимушені коливання елементів конструкцій з урахуванням та без урахування взаємодіє з рідиною. Для в’язкої стисливої рідини отримано формулювання задачі в акустичному наближенні. Числова реалізація здійснена в припущенні безвихрового руху ідеальної та нестисливої рідини. Для розв’язання задачі з визначення тиску рідини отримано рівняння Лапласа з умовами не протікання в якості крайових. Задачу визначення гідродинамічного тиску із застосуванням методів теорії потенціалу зведено до розв’язання гіперсингулярного інтегрального рівняння. Форми власних коливань конструктивного елементу без врахування приєднаних мас рідини обрані як базисні для розв’язання задачі визначення динамічних характеристик з урахуванням рідини. Як приклад розглянуті власні частоти та форми коливань круглої пластинки як без урахування впливу рідини, та з її урахуванням. Досліджені також гармонічні коливання цієї пластинки.

Waste materials assessment for phosphorus adsorption toward sustainable application in circular economy

Phosphorus is the main determinant of nutrient enrichment in the water bodies. Many resources including nutrients may be shortly exhausted, assuming current consumption. This scenario leads to growing interest in resources recovery and/or reuse, which together with sustainable energy consumption and waste reduction are the main courses of the circular economy. Usage of coagulants in wastewater treatment plants (WWTP) does not allow phosphorus to be recovered from the sludge. An alternative method with recovery potential is the application of adsorbents. Many adsorbents have been approved for P-removal, however some of them are expensive. Response to that issue may be the application of waste materials and byproducts often intended for disposal/utilization. The main objective was to assess the P-removal efficiency of the waste materials/byproducts for application in small WWTP and eco-technologies like treatment wetlands as replacement of commercial adsorbents and alternative for conventional (chemical) treatment for potential phosphorus recovery. The materials investigated were (1) an expensive man-made product, (2) a byproduct with a high content of calcium oxide, and (3) drinking water treatment residuals (DWTRs) as beds from filters used to remove iron. Research was conducted in non-flow condition with various initial concentrations. The highest efficiency was received for fine-grained byproduct (9.58 mg/g), for commercial adsorbent LMB - 9.11 mg/g. The DWTRs adsorption was oscillated around 4.5 mg/g. These results confirmed the possibility of applying waste materials and byproducts for P-removal according to the circular economy idea. Further research should include implications of waste materials application to determine P-recovery concept.

A Simplified Analytical Model for Estimation of the Initial Waterhammer Pressure and Force on a Circular Tube

Abstract A simplified analytical model is developed for estimating the initial waterhammer pressure and force on a circular tube when a plane decompression wave, parallel to its axis, passes over it. The simplified analysis superimposes the solutions for a plane pressure wave traveling at sound speed in the surrounding water, and two-dimensional solution to the wave equation in cylindrical coordinates, with a nonflow boundary condition across the tube boundary at a fixed radius. The analytical method is compared to the computational fluid dynamics (CFD) approach by applying to predict the initial waterhammer pressure and force on the closest tube to the feedwater nozzle of a geometrically simplified nuclear steam generator (SG) analysis model, caused by a feedwater pipe break (FWPB). As the result, it is found that the simplified analytical model, while not matching results of the CFD calculations with precise accuracy, does confirm the nature of the waterhammer impact pressure loads on the SG tubes.

Identification of an extracytoplasmic function sigma factor that facilitates c-type cytochrome maturation and current generation under electrolyte-flow conditions in Shewanella oneidensis MR-1.

Shewanella oneidensis MR-1 was cultured on electrodes in electrochemical flow cells (EFCs), and transcriptome profiles of electrode-attached cells grown under electrolyte-flow conditions were compared with those under static (nonflow) conditions. Results revealed that, along with genes related to c-type cytochrome maturation (e.g., dsbD), the SO_3096 gene encoding a putative extracytoplasmic function (ECF) sigma factor was significantly upregulated under electrolyte-flow conditions. Compared to wild-type MR-1 (WT), an SO_3096-deletion mutant (∆SO_3096) showed impaired biofilm formation and decreased current generation in EFCs, suggesting that SO_3096 plays critical roles in the interaction of MR-1 cells with electrodes under electrolyte-flow conditions. We also compared transcriptome profiles of WT and ∆SO_3096 grown in EFCs, confirming that many genes upregulated under the electrolyte-flow conditions, including dsbD, are regulated by SO_3096. LacZ reporter assays showed that transcription from a promoter upstream of dsbD is activated by SO_3096. Measurement of current generated by a dsbD-deletion mutant revealed that this gene is essential for the transfer of electrons to electrodes. These results indicate that the SO_3096 gene product facilitates c-type cytochrome maturation and current generation under electrolyte-flow conditions. The results also offer ecophysiological insights into how Shewanella regulates extracellular electron transfer to solid surfaces in the natural environment.

Real Time 3D Observations of Portland Cement Carbonation at CO2 Storage Conditions.

Depleted oil reservoirs are considered a viable solution to the global challenge of CO2 storage. A key concern is whether the wells can be suitably sealed with cement to hinder the escape of CO2. Under reservoir conditions, CO2 is in its supercritical state, and the high pressures and temperatures involved make real-time microscopic observations of cement degradation experimentally challenging. Here, we present an in situ 3D dynamic X-ray micro computed tomography (μ-CT) study of well cement carbonation at realistic reservoir stress, pore-pressure, and temperature conditions. The high-resolution time-lapse 3D images allow monitoring the progress of reaction fronts in Portland cement, including density changes, sample deformation, and mineral precipitation and dissolution. By switching between flow and nonflow conditions of CO2-saturated water through cement, we were able to delineate regimes dominated by calcium carbonate precipitation and dissolution. For the first time, we demonstrate experimentally the impact of the flow history on CO2 leakage risk for cement plugging. In-situ μ-CT experiments combined with geochemical modeling provide unique insight into the interactions between CO2 and cement, potentially helping in assessing the risks of CO2 storage in geological reservoirs.

Property Decoupling across the Embryonic Nucleus-Melt Interface during Polymer Crystal Nucleation.

Spatial distributions are presented that quantitatively capture how polymer properties (e.g., segment alignment, density, and potential energy) vary with distance from nascent polymer crystals (nuclei) in prototypical polyethylene melts. It is revealed that the spatial extent of nuclei and their interfaces is metric-dependent as is the extent to which nucleus interiors are solid-like. As distance from a nucleus increases, some properties, such as density, decay to melt-like behavior more rapidly than polymer segment alignment, indicating that a polymer nucleus resides in a nematic-like droplet. This nematic-like droplet region coincides with enhanced formation of ordered polymer segments that are not part of the nucleus. It is more favorable to find nonconstituent ordered polymer segments near a nucleus than in the surrounding metastable melt, pointing to the possibility of one nucleus inducing the formation of other nuclei. In this vein, there is also a second region of enhanced ordering that lies along the nematic director of a nucleus, but beyond its nematic droplet and fold regions. These results indicate that crystal stacking, a key characteristic of lamellae in semicrystalline polymeric materials, begins to emerge during the earliest stages of polymer crystallization (i.e., crystal nucleation). More generally, the findings of this study provide a conceptual bridge between polymer crystal nucleation under nonflow and flow conditions and are used to rationalize previous results.

Photocatalytic biocidal effect of copper doped TiO2 nanotube coated surfaces under laminar flow, illuminated with UVA light on Legionella pneumophila.

Legionella pneumophila can cause a potentially fatal form of humane pneumonia (Legionnaires’ disease), which is most problematic in immunocompromised and in elderly people. Legionella species is present at low concentrations in soil, natural and artificial aquatic systems and is therefore constantly entering man-made water systems. The environment temperature for it’s ideal growth range is between 32 and 42°C, thus hot water pipes represent ideal environment for spread of Legionella. The bacteria are dormant below 20°C and do not survive above 60°C. The primary method used to control the risk from Legionella is therefore water temperature control. There are several other effective treatments to prevent growth of Legionella in water systems, however current disinfection methods can be applied only intermittently thus allowing Legionella to grow in between treatments. Here we present an alternative disinfection method based on antibacterial coatings with Cu-TiO2 nanotubes deposited on preformed surfaces. In the experiment the microbiocidal efficiency of submicron coatings on polystyrene to the bacterium of the genus Legionella pneumophila with a potential use in a water supply system was tested. The treatment thus constantly prevents growth of Legionella pneumophila in presence of water at room temperature. Here we show that 24-hour illumination with low power UVA light source (15 W/m2 UVA illumination) of copper doped TiO2 nanotube coated surfaces is effective in preventing growth of Legionella pneumophila. Microbiocidal effects of Cu-TiO2 nanotube coatings were dependent on the flow of the medium and the intensity of UV-A light. It was determined that tested submicron coatings have microbiocidal effects specially in a non-flow or low-flow conditions, as in higher flow rates, probably to a greater possibility of Legionella pneumophila sedimentation on the coated polystyrene surfaces, meanwhile no significant differences among bacteria reduction was noted regarding to non or low flow of medium.

Flow Water Proton NMR: In-Line Process Analytical Technology for Continuous Biomanufacturing.

Continuous manufacturing of biologics is one of the priorities of the biopharmaceutical industry. However, its widespread implementation is hampered by a lack of noninvasive/nondestructive process analytical technology (PAT) systems capable of real-time in-line monitoring of product flow parameters, such as concentration and/or aggregate content. We have previously demonstrated that, under nonflow conditions, the water proton transverse relaxation rate, R2(1H2O), is sensitive to protein concentration and aggregate content in biopharmaceutical formulations. In the present work, we explored the potential of water proton NMR under flow conditions (flow-wNMR) to use R2(1H2O) as a quantitative indicator of protein concentration variations and aggregate levels in the process flow. We show that, under flow conditions, R2(1H2O) is sensitive to rather small changes in protein concentration (<1 mg/mL) and is capable to detect variations in the aggregate content of <1%. Our findings suggest that flow-wNMR could be advantageously used as a real-time in-line noninvasive PAT for continuous biomanufacturing.

Effect of homogenization and hot rolling on the mechanical properties, microstructure and corrosion behavior of U–10Mo monolithic fuel

Corrosion behavior is an important consideration in the fuel qualification process. No prior study comprehensively evaluated the corrosion behavior of uranium-10 wt percent (wt%) molybdenum alloy for use in U.S. High Performance Research Reactors with the current composition, thermomechanical processing methods, dimension, cladding material, interface, research reactor water chemistry, temperature, and flow conditions. Hence, this work was performed to obtain baseline information about the corrosion behavior of DU-10Mo (depleted uranium-10 wt% molybdenum) alloy as a function of fabrication parameters (homogenization and hot rolling) using deionized water in a non-flow condition at 23 °C and 75 °C. Electrochemical and immersion corrosion testing were performed to determine the corrosion behavior of DU-10Mo hot-rolled foils. Microhardness testing, optical microscopy, and scanning electron microscopy were performed to evaluate the effect of fabrication parameters on DU-10Mo.

Rotational and vibrational temperatures in the spark plasma by various discharge energies and strategies

Increasing discharge energies and employing advanced discharge strategies have been deemed to be effective methods for improving the ignition processes, especially for diluted or lean combustion. However, so far knowledge on the relevant mechanism is far from adequate. In particular, the effects of the plasma produced between the spark plug electrodes on spark ignition processes need to be further clarified. The plasma temperatures are important as they are closely related to the chemical reaction rate. In this study, the vibrational and rotational temperatures of the discharge plasma are quantitatively evaluated by a time series of spectral measurements with different discharge energies and strategies in air under atmospheric pressure, based on the N2 second positive molecular emission spectra. The vibrational and rotational temperatures show a perfect consistent trend with the release rates of delivered energy to the spark plug gap. This indicates that the two temperatures can be enhanced by the higher energy release rates and can be effectively controlled by different discharge strategies. The vibrational and rotational temperatures measured in this study are in the range of 3700–4300 K and 1400–2600 K, respectively. The temperature differences between the vibrational and rotational temperatures exceed 1600 K, increasing with the energy release rate decreasing. This indicates that the spark discharge plasma is in a state of non-thermal equilibrium with the existence of the discharge energies under the non-flow conditions. These results would be a reference to further develop the advanced discharge strategies and improve the ignition stability.