Fractional Hartley transform on $G$-Boehmian space

Using a special type of fractional convolution, a $G$-Boehmian space $\mathcal{B}_\alpha$ containing integrable functions on $\mathbb{R}$ is constructed. The fractional Hartley transform ({\sc frht}) is defined as a linear, continuous injection from $\mathcal{B}_\alpha$ into the space of all continuous functions on $\mathbb{R}$. This extension simultaneously generalizes the fractional Hartley transform on $L^1(\mathbb{R})$ as well as Hartley transform on an integrable Boehmian space.

Asphaltene Mitigation in Giant Carbonate Abu Dhabi Fields: A Techno-Economic Comparison Between Continuous Injection and Formation Squeeze

Asphaltene deposition is a serious and re-occurring flow assurance problem in several of the ADNOC onshore oilfields. Fluids are intrinsically unstable with respect to asphaltene precipitation, and operating conditions are such that severe deposition occurs in the wellbore. Wells in ADNOC are generally not equipped with downhole chemical injection lines for continuous inhibition, and protection of the wells require frequent shut-in and intervention by wireline and coiled tubing to inspect and clean up. Since some of the mature fields are under EOR recovery strategies, like miscible hydrocarbon WAG and CO2 flood, which exacerbates the asphaltene precipitation and deposition problems, a more robust mitigation strategy is required. In this paper the results of two different mitigation strategies will be discussed; continuous injection of asphaltene inhibitor via a capillary line in the tubular and asphaltene inhibitor formation squeeze. Three asphaltene inhibitors from different suppliers were pre-qualified and selected for field trial. Each inhibitor was selected for a formation squeeze in both one horizontal and one vertical well, and one of the inhibitors was applied via thru-tubing capillary string. The field trials showed that continuous injection in remote wells with no real-time surveillance options (e.g. gauges, flow meters) is technically challenging. The continuous injection trial via the capillary string was stopped due to technical challenges. From the six formation squeezes four were confirmed to be effective. Three out of fours squeezes significantly extended the production cycle, from approximately 1.4 to 6 times the normal uninhibited flow period. The most successful squeezes were in the vertical wells. The results of the trial were used to model the economic benefit of formation squeeze, compared to a ‘do-nothing’ approach where the wells are subject to shut-in and cleanup once the production rates drop below a threshold value. The model clearly indicates that the squeezes applied in ADNOC Onshore are only cost-effective if it extends the normal flow period by approximately three times. However, a net gain can be achieved already if the formation squeeze extends the flow cycle by 15 to 20%, due to reduction of shut-in days required for intervention. Therefore, the results in this paper illustrate that an asphaltene inhibitor formation squeeze can be an attractive mitigation strategy, both technically and economically.

Simulation of the Scattering of Continuously Injected Pickup Ions outside the Heliopause

Hybrid simulations in 2D space and 3D velocity dimensions with continuous injection of pickup ions (PUIs) provide insight into the plasma processes that are responsible for the pitch angle scattering of PUIs outside the heliopause. The present investigation includes for the first time continuous injection of PUIs and shows how the scattering depends on the energy of the PUIs and the strength of the background magnetic field as well as the dependence on the injection rate of the time for the isotropization of the pitch angle distribution. The results demonstrate that, with the gradual injection of PUIs of a narrow ring velocity distribution perpendicular to the background magnetic field, oblique mirror mode waves develop first, followed by the growth of quasiparallel propagating ion cyclotron waves. Subsequently, the PUIs are scattered by the excited waves and gradually approach an isotropic distribution. A time for isotropization is defined to be the time at which T ∣∣/T ⊥, i.e., the ratio of the parallel to perpendicular PUI thermal energy changes from ≈0 to ≈0.15. By varying the PUI injection rate, estimates of the time for the PUI distribution to be isotropized are presented. The isotropization time obtained is shorter, ≈ months, than the time, ≈ years, required by the conventional secondary ENA mechanism to explain the IBEX ENA ribbon.

When are maps preserving semi-inner products linear?

We observe that every map between finite-dimensional normed spaces of the same dimension that respects fixed semi-inner products must be automatically a linear isometry. Moreover, we construct a uniformly smooth renorming of the Hilbert space $$\ell _2$$ ℓ 2 and a continuous injection acting thereon that respects the semi-inner products, yet it is non-linear. This demonstrates that there is no immediate extension of the former result to infinite dimensions, even under an extra assumption of uniform smoothness.

Diffusion dynamics controlled colloidal synthesis of highly monodisperse InAs nanocrystals

Highly monodisperse colloidal InAs quantum dots (QDs) with superior optoelectronic properties are promising candidates for various applications, including infrared photodetectors and photovoltaics. Recently, a synthetic process involving continuous injection has been introduced to synthesize uniformly sized InAs QDs. Still, synthetic efforts to increase the particle size of over 5 nm often suffer from growth suppression. Secondary nucleation or interparticle ripening during the growth accompanies the inhomogeneity in size as well. In this study, we propose a growth model for the continuous synthetic processing of colloidal InAs QDs based on molecular diffusion. The experimentally validated model demonstrates how precursor solution injection reduces monomer flux, limiting particle growth during synthesis. As predicted by our model, we control the diffusion dynamics by tuning reaction volume, precursor concentration, and injection rate of precursor. Through diffusion-dynamics-control in the continuous process, we synthesize the InAs QDs with a size over 9.0-nm (1Smax of 1600 nm) with a narrow size distribution (12.2%). Diffusion-dynamics-controlled synthesis presented in this study effectively manages the monomer flux and thus overcome monomer-reactivity-originating size limit of nanocrystal growth in solution.

Hand-compression pressure cooker: an innovative variation of an existing technique with two example cases

The pressure cooker technique was originally ideated to obtain wedge-flow conditions during arteriovenous malformation or arteriovenous fistula embolisation. The anti-reflux plug created with coils or glue around the tip of a detachable microcatheter enables a continuous injection with a more in-depth penetration. Here we describe two illustrative cases performed with a variation of the technique that we describe as the hand-compression pressure cooker technique.

Injection-rolling nozzle in an imprint system with continuous injection direct rolling for ultra-thin microstructure guide light plate

A novel Injection-rolling Nozzle (IRN) in an imprint system with continuous injection direct rolling (CIDR) for ultra-thin microstructure polymer guide light plates was developed to achieve uniform flow velocity and temperature at the width direction of the cavity exit. A novel IRN cavity was designed. There are eight of feature parameters of cavity were optimized by orthogonal experiments and numerical simulation. Results show that the flow velocity at the width direction of the IRN outlet can reach uniformity, which is far better than that of traditional cavity. The smallest flow velocity difference and temperature difference was 0.6 mm/s and 0.24 K, respectively. The superior performance of the IRN was verified through a CIDR experiment. Several 0.35-mm thick, 340-mm wide, and 10-m long microstructural Polymethyl Methacrylate (PMMA) guide light plates were manufactured. The average filling rates of the microgrooves with the aspect ratio 1:3 reached above 93%. The average light transmittance is 88%.

MODERN METHODOLOGICAL POSSIBILITIES OF THE TRACER METHOD FOR ASSESSING THE COVERAGE OF AN OIL RESERVOIR BY FLOODING

The article presents the results of modeling tracer studies of the process of flooding of an oil reservoir. As a result of the studies, the dependences on the time of the change in the volume occupied by the injected water were obtained. Formulas are given that allow us to calculate the values of the coefficient of coverage of the reservoir area by flooding as a whole and the contribution of each injection well to flooding. The technology is implemented by continuously pumping the tracer into the injection well. Continuous injection of different tracers into different injection wells allows for operational monitoring of oil field development

Offshore Heavy Oil Polymerflooding Pilot Reveals Alternative Paths

This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper OTC 30277, “Twelve-Year Field Applications of Offshore Heavy Oil Polymerflooding From Continuous Injection to Alternating Injection of Polymer and Water,” by Guangming Pan, Lei Zhang, and Jianting Huang, CNOOC, et al., prepared for the 2020 Offshore Technology Conference Asia, originally scheduled to be held in Kuala Lumpur, 2-6 November. The paper has not been peer reviewed. Copyright 2020 Offshore Technology Conference. Reproduced by permission. Polymerflooding has been considered a suitable method for reservoirs with viscosities up to 150 mPa·s. The authors of the complete paper verify that alternating injection of polymer and water in the Bohai Bay of China proved effective and economical for heavy oil fields, even offshore. This polymerflooding pilot of initially continuous, and then alternating, injection can provide a useful technical reference for similar reservoirs. Introduction Heavy oil reserves are abundant in the Bohai oil field of China. The development of the field has proved that the field with lower viscosity (less than 350 mPa·s) can be developed effectively by water-flooding, while the unconventional heavy oil reservoir with high viscosity has not formed a mature development mode. To better use interwell reserves, a pilot polymerflooding test has been conducted in the NN field since 2008. The cumulative production of nine wells in the surrounding area reached 10.80×104 m3, which confirmed that polymer fluid injection had a good displacement effect on unconventional high-viscosity crude oil. However, with the extension of continuous injection time, the pilot test area faced various problems. In order to explore the applicability of polymerflooding technology used in offshore unconventional heavy oil fields, the polymer-injection mode was studied on the basis of laboratory experimental data and field practice, and the polymer/water alternating injection mode was analyzed. Experimental Continuous Polymerflooding. Experimental Equipment and Materials. The experimental device is composed of a driving system, an experimental model, a pressure-measurement system, a produced-liquid-collection system, and a temperature-control system. According to the distribution of reservoir physical properties in the NN field, a parallel double-tube displacement experiment with a permeability ratio of 5 was designed. The experimental cores are artificial, with a tube length of 30 cm and an inner diameter of 2.54 cm. The low-permeability tube has 1624×10-3 µm2 permeability, and the high-permeability tube has 8488×10-3 µm2 permeability. The experimental temperature is 55°C, which is consistent with the formation temperature of the NN field. The polymer is partially hydrolyzed polyacrylamide. Experimental Procedure. The experimental process includes vacuum pumping, saturating formation water, obtaining core pore volume, saturating simulated oil, calculating oil saturation water drive to a specified water cut, continuously injecting polymer solution, and measuring data. The experimental injection rate is 0.2 mL/min, and the multiple of injected pore volumes (PV) is 0.6 PV. The NN field has weak edge water, and the water cut of the well group was 60 to 90% when polymerflooding was performed. Therefore, the design scheme mainly includes waterflooding and polymerflooding stages. The polymer- injection concentration was 3000 mg/L, and the injection mode is continuous, consistent with the field test.