Separation Device Research Articles

Capillary and Electrodynamic Forces-Driven Separation Detection of Metal Ions Using a Disposable Microfluidic Sensor with a Composite Electrode.

A disposable microfluidic channel sensor printed on a plastic platform was developed to analyze heavy metal ions (HMIs) as a model target species. Precise separation and detection of multiple targets were established by symmetrically applying a small AC potential on the carbon channel walls to induce an electrodynamic force. The separation device was constructed by covering it with a plastic lid to achieve capillary action in the channel. The sample flow rate was regulated by the hydrophilicity of the lid plastic and electrodynamic convection by the AC field, which was characterized by the contact angle measurement and the additional electrodynamic force. The flow variables and their relevance to the capillary phenomena were demonstrated, and the analytical parameters were optimized. The working electrode was modified with poly(diamino terthiophene) anchored with nanosized graphene oxide (pDATT/GO) to enhance the detection performance. The experimental variables for separating and detecting the target species were optimized according to the AC frequency and amplitude, sample flow rate, electrolytes, pH, temperature, and applied potential for detection. The linear dynamic ranges were between 0.1 and 200.0 ppb, with detection limits of 0.04 ± 0.023, 0.29 ± 0.05, 0.07 ± 0.011, and 0.14 ± 0.06 ppb for Cu2+ Cd2+, Hg2+, and Pb2+, respectively. Finally, the reliability of the proposed method was evaluated through analysis of HMIs in real water samples. The results were matched to those obtained through parallel analysis using ICP-MS at a 95% confidence level.

Improving efficiency of flat-chamber electrobaromembrane device for solution separation

Improving efficiency of flat-chamber electrobaromembrane device for solution separation

Separation of binary and ternary oil/water mixtures from a highly hydrophobic metal mesh.

A highly hydrophobic metal mesh has great potential for its application in oil/water separation due to its special wettability. However, most current oil/water separation devices are simple with limited separation capacity. A separation device based on a highly hydrophobic metal mesh was constructed for different types of oil/water mixtures. Experimental results show that the device not only can be used for the continuous separation of binary oil/water mixtures of any density ratios but also can realize the simultaneous separation of heavy oil/water/light oil ternary mixtures. This achievement is meaningful for practical applications, which will gain great interest in the future.

Integrated electro-optic control of biphoton generation using hybrid photonics

Parametric sources in quantum optics usually require some form of spectro-temporal control for conditional generation of high-purity single-photon states, but their properties have not yet been optimized using integrated microchips. Using external short-pulse lasers and separate devices for pump preparation and for photon generation, as is traditional, incurs many impediments such as reduced performance, increased loss, high cost, and limited scalability. To overcome these limitations, here we demonstrate a circuit including high-bandwidth, high-extinction ratio electro-optic modulators for pump-pulse preparation fully integrated with high-quality factor (Q) microresonators for efficient parametric nonlinearity, together with seamlessly interconnecting waveguides. The microchip uses different optical materials on a common platform and a multi-layer integrated photonic architecture. Using this, we control the joint spectrum of room-temperature biphoton generation for the first time on a single integrated microchip, and demonstrate that the theoretical purity bound can be achieved.

Three-dimensional hydrophobic melamine@methyl trichlorosilane/polydimethylsiloxane sponge for consecutive and long-term oil/water separation

Herein, a melamine sponge is adopted as the skeleton to be modified by both methyl trichlorosilane (MTS) and polydimethylsiloxane (PDMS) on the surface, fabricating the 3D porous Mel@MTS/PDMS sponge. Systemic investigations reveal that MTS self-assembles into many micro-nano particles to roughen the surface of the melamine matrix, thus greatly increasing its hydrophobicity. PDMS tightly anchors those MTS particles via forming a surface coating. Therefore, the resultant Mel@MTS/PDMS sponge exhibits the superior oil-adsorbed capacity, good hydrophobicity, and great structural and mechanical stability. Based on this Mel@MTS/PDMS sponge, a consecutive oil/water separation system is successfully built and induces the continuous recovery of oil under various simulated oil–water separation conditions. Obviously, this 3D hydrophobic Mel@MTS/PDMS sponge and corresponding consecutive oil/water separation device provide a promising application strategy in the leaked oil recovery and environmental purification.

Analysis of Separation Efficiency Focusing on Particle Concentration and Size Using a Spiral Microfluidic Device

This study discusses component separation using a microfluidic device. Based on the separation principle, a method was adopted to generate an external force due to centrifugal force in a spirally designed channel. In this study, four types of polystyrene particles with different diameters ranging within 1–45 µm were used, and the separation performance was evaluated for each particle size. The centrifugal force increased as the flow velocity in the channel increased; however, this time, the test was conducted with the flow rate, which is an input parameter fixed at 100 µL/min. The results of the micro-channel observation using a high-speed camera indicated that the particle density might be a factor in the decrease in separation efficiency. Therefore, by conducting tests at three different particle densities, we were able to experimentally investigate the change in separation efficiency based on the particle size and density. In this study, we considered the separation efficiency due to the size and density of the particle diameter along with its application to an onsite-type separation device.

Development of a baby cot with temperature and weight monitoring features: Focus on parents with phocomelia and upper limb amputation

Caring for an infant is a tough and demanding task that presents various challenges for parents. This is especially true for parents who have physical disabilities, as they face unique obstacles in their caregiving journey. For parents with limited movement in their upper limbs, keeping track of important aspects of their baby's health, like weight and temperature, can be a difficult and exhausting task, necessitating innovative solutions to ensure that these parents can provide the best possible care for their child while also promoting their independence. While previous studies have established technology that enhance baby's comfort and safety in cradles and cots, and in contrast to existing products that may require separate monitoring devices or manual interventions, this work presents a significant shift by focusing on the specific needs of parents with phocomelia and upper limb amputation, to enable them to provide independent and attentive infant care. We developed a voice recognition-controlled smart baby cot equipped with real-time temperature and weight monitoring features, and a liquid-crystal display (LCD) feedback, to assist such parents in predicting their baby's well-being. We conducted both finite element analysis (FEA) and ten experimental performance evaluations on the prototype, with and without a load (baby) to assess the cot's load-bearing capacity across different positions, its sensitivity to household noise, and consistency in temperature and weight reading. Our findings demonstrated consistent load-bearing capability and precise weight and temperature measurements, with an overall standard error of 0.03. The voice activation system also performed effectively in environments with noise levels below 80 dB. This work promotes parental autonomy and has the potential to benefit infants and parents in various contexts, including resource-constrained settings. Additionally, it aligns with the global discourse on inclusive healthcare and technology, contributing to the objectives of Africa's Agenda 2063 and Sustainable Development Goal (SDG) 3.

High efficiency and selective separation of oily wastewater based on superamphiphilic biomass aerogel: Characteristics, mechanisms and application

The design and development of multifunctional materials to meet the sophisticated requirements of oily wastewater treatment is an urgent need and remains a great challenge. Herein, a superamphiphilic bio-aerogel (PTGA) with honeycomb-like porous structure was synthesized. The directional and reversible control of interfacial wettability can be achieved by simple pre-wetting process and solvent replacement method. Combined with the advantages of structure and wettability, PTGA was proved to be ideal for high-efficient oil-water mixture separation (J> 1500 L/m2·h, η > 99.8%), oils absorption (Cabs = 17–26 g/g) and dye selective removal (MO: 73.552 mg/g, MB: 45.876 mg/g). Furthermore, based on the newly developed dynamic separation device and excellent mechanical property of PTGA, enhanced separation of oil-water mixture (J = 3007 L/m2·h) and synergistic removal of co-existing pollutants (MB: 51.274 mg/g) were realized. Mechanism results indicated that the transition of interfacial wetting properties of PTGA was a multi-stage process, while oil/water separation and dye adsorption were two independent processes. Benefit from facile synthesis and unparalleled characteristics, the designed PTGA promise to be reliable and competitive candidates in wastewater remediation.

Flow Field Pattern and Hydrodynamic Characteristics of a Grid Device Made with Various Grid Bar Spacings at Different Inclination Angles

The grid is a crucial component in constructing grid-type bycatch reduction devices. The grid’s structural characteristics and orientation significantly impact the hydrodynamic characteristics and efficacy of the separation device. Therefore, it is essential to thoroughly understand the grid device’s hydrodynamic characteristics and flow field to optimize its structure. Thus, this study used CFD numerical simulation and flume tank experiments to investigate the effects of inclination grid angles and grid bar spacing on hydrodynamic forces and flow fields around a circular grid. The results indicated that the hydrodynamic forces acting on the circular grid increased with higher flow velocity and inclination grid angle, decreasing with smaller grid bar spacing. Flow velocity acceleration zones were observed at the upper and lower ends of the grid and between the grid bars. Additionally, upwelling and vortices were present at the back of the grid. It was found that an increase in the inclination grid angle accelerated the vortex and wake effects.

Performance of two plasma separation devices for HIV-1 viral load measurement in primary healthcare settings.

Dried blood spot (DBS) may overestimate the viral RNA, mainly in patients with low viral load (VL), due to proviral DNA and intracellular RNA. The Burnett and HemaSpot provide integrated solutions for the collection, separation, and drying of plasma from whole blood. This study aims to evaluate the performance of both devices compared to plasma to identify antiretroviral therapy (ART) failure. The devices were separately evaluated in a cross-sectional design. Patients on ART were included for the studies (Burnett: 611, October 2019 to January 2020) and (HemaSpot: 620, November 2020 to April 2021). VL was tested using CAP/CTM96. The sensitivity and specificity of DBS, Burnett, and HemaSpot were determined, and plasma results were considered as a reference at a threshold of 1,000 copies/ml. For the Burnett study, 2,444 specimens, including plasma, DBS, venous Burnett (vBurnett), and capillary Burnett (cBurnett), were collected. Sensitivity of DBS, vBurnett, and cBurnett was 97.4%, 98.3%, and 97.5%, respectively, whereas specificity was 86.8% for DBS, 96.9% for vBurnett, and 93.9% for cBurnett. For the HemaSpot study, 1,860 specimens were collected, including plasma, DBS, and vHemaSpot. Sensitivity of DBS and vHemaSpot was 95.0% and 91.3%, respectively, whereas specificity was 86.9% for DBS and 94.5% for vHemaSpot. The misclassification rate was more prominent in DBS (4.8%) and HemaSpot (8.4%) but lower in vBurnett (2.0%) and cBurnett (3.2%). The Burnett showed better performance than DBS, whereas HemaSpot showed poorer performance than DBS. Nevertheless, both Burnett and HemaSpot have high rate of non-reportable results. In the current format, neither of the two devices is feasible for VL scale-up in resource-limited settings.IMPORTANCEBurnett and HemaSpot are two novel technologies that allow whole blood collection and plasma separation and stabilization at room temperature without the need of additional equipment. Hence, these devices are potential alternatives to fresh plasma as a suitable specimen for viral load scale-up to monitor antiretroviral therapy in resource-limited settings.

Stiffness influence on particle separation in polydimethylsiloxane-based deterministic lateral displacement devices

Polydimethylsiloxane (PDMS) is a popular material to rapidly manufacture microfluidic deterministic lateral displacement (DLD) devices for particle separation. However, manufacturing and operation challenges are encountered with decreasing device dimensions required to separate submicron particles. The smaller dimensions, notably, cause high hydraulic resistance, resulting in significant pressure even at relatively low throughputs. This high pressure can lead to PDMS deformation, which, in turn, influences the device performance. These effects may often be overlooked in the design and operation of devices but provide a systematic source of error and inaccuracies. This study focuses in detail on these effects and investigates pillar deformation in detail. Subsequently, we discuss a potential solution to this deformation using thermal annealing to stiffen the PDMS. We evaluate the influence of stiffness on the separation performance at elevated sample flow rates with submicron particles (0.45 and 0.97 µm diameter). An excellent separation performance at high throughput is successfully maintained in stiffer PDMS-based DLD devices, while the conventional devices showed decreased separation performance. However, the increased propensity for delamination constrains the maximal applicable throughput in stiffer devices. PDMS deformation measurements and numerical simulations are combined to derive an iterative model for calculating pressure distribution and PDMS deformation. Finally, the observed separation characteristics and encountered throughput constraints are explained with the iterative model. The results in this study underline the importance of considering pressure-induced effects for PDMS-based DLD devices, provide a potential mitigation of this effect, and introduce an approach for estimating pressure-induced deformation.

Impact of 3D-printed laboratory equipment in vibrations and controls courses on student engineering identity, motivation, and mindset

This paper describes the implementation of innovative 3D-printed laboratory equipment linked to inquiry-based learning activities designed to improve learning, increase engineering identity and motivation, and foster a growth mindset in students taking undergraduate level mechanical vibrations courses, control theory courses, and associated laboratories. These innovative designs create new opportunities for hands-on learning, are low-cost, portable, and can be adapted for use in multiple science and engineering disciplines. The learning activities are based on the POGIL model, which has been used across a variety of disciplines including engineering. We describe the features of three separate devices (spring-connected sliding carts, compliant parallel arms with fixed-free ends and a slider mass, and a pendulum with variable tip load) implemented using a quasi-experimental approach with 510 duplicated students across three semesters during the COVID-19 pandemic in multiple lecture courses and laboratory sections. We also present an assessment of impact based on descriptive statistical analyses of survey data for student-reported learning gains and pre-post paired comparison tests on validated instruments measuring perceptions of engineering identity, engineering motivation, and growth mindset. Further, we conducted a student focus group and include salient instructor observations. Results show most students participating in the learning activities using these devices report that it supported their learning “a lot” or “a great deal.” In addition, on six of seven surveyed learning outcomes, most students reported feeling confident enough to complete them on their own or even teach them to someone else. Our data did not show a measurable impact on engineering identity, engineering motivation, or growth mindset, though it does suggest further investigation is merited.

Applications of macrocycle-based solid-state host-guest chemistry.

Macrocyclic molecules have been used in various fields owing to their guest binding properties. Macrocycle-based host-guest chemistry in solution can allow for precise control of complex formation. Although solution-phase host-guest complexes are easily prepared, their limited stability and processability prevent widespread application. Extending host-guest chemistry from solution to the solid state results in complexes that are generally more robust, enabling easier processing and broadened applications. Macrocyclic compounds in the solid state can encapsulate guests with larger affinities than their soluble counterparts. This is crucial for use in applications such as separation science and devices. In this Review, we summarize recent progress in macrocycle-based solid-state host-guest chemistry and discuss the basic physical chemistry of these complexes. Representative macrocycles and their solid-state complexes are explored, as well as potential applications. Finally, perspectives and challenges are discussed.

Research and Practice of Intelligent Separate Production Technology with Cable in Huabei Oilfield

In order to improve the separate production effect of sandstone reservoir in Huabei Oilfield and give full play to the production capacity of medium and low permeability layers, the intelligent separate production technology with cable is designed and developed. The technology uses cable packer to seal each layer in the well, and a set of intelligent separate production device is connected to the corresponding string position of each target layer. During the production process, the intelligent separate production device can send instructions according to the ground control center Open or close the oil layer to realize the exploitation of any layer and multi-layer co production of any layer. It can accurately measure the liquid production and properties of each section of the well, and calculate the formation permeability, skin factor and other parameters by sections, so as to realize the continuous testing and monitoring function.In the later stage, the switch opening can be adjusted by remote control to adjust the output of each layer in time to meet different production allocation requirements and achieve the purpose of increasing oil and reducing water, which is of great significance to realize the accurate development of the reservoir.

A unified approach to thermo-mechano-caloric-characterization of elastocaloric materials

This paper presents a novel approach to characterizing the relevant mechanical, thermal and caloric properties of elastocalorics material in a single testing device. Usually, tensile experiments are performed to determine the rate- and process-depending stress/strain behavior of nickel-titanium-based shape memory alloys and potentially other elastocaloric materials made from metallic alloys. These tests are relevant for, e.g., characterization of hysteresis properties and subsequent calculation of mechanical work input. In addition, simultaneous observation with an infrared camera is useful to understand temperature evolution and maximum temperature changes achievable during the loading/unloading process. Characterization of the caloric properties of the materials determines latent heats and, together with the mechanical work, also the material coefficient of performance. It is typically carried out via differential scanning calorimetry (DSC), which is performed in a separate device and requires a second experiment with different types of samples. Furthermore, DSC measurements do not reflect the way mechanically induced phase transformations trigger the release and absorption of latent heats as it is the case for elastocalorics. In order to provide a more consistent understanding of the relevant elastocaloric material properties, we here present a novel method that (a) allows for a systematic determination of load-dependent latent heats and (b) introduces a comprehensive testing setup and suitable testing routine to determine the mechanical, thermal and caloric parameters in the same experimental device and with the same sample, thus greatly simplifying the overall procedure.

Purposes and patterns of the use of antique sources in old English religious texts by Ælfric and Wulfstan

The article contains the results of the analysis of existing investigations into the ways how Latin religious sources were adopted and adapted in Anglo-Saxon homiletic literature. The present analysis may be of value when it is important to understand how religious contexts were borrowed and presented to a different culture, moreover the motives of adaptation of Latin texts may add to better understanding of the writer’s personalities and thus to a clearer insight into their works. Two eminent old English writers: Aelfric and Wulfstan worked closely with Latin texts following various strategies. While Aelfric in most cases translated the texts verbatim or slightly modified them, Wulfstan put much effort to give the text his own personality. Both writers still depended on the rhetoric traditions employed in Latin and their individual styles coincide in with usage of some stylistic features such as assonance, alliteration and repetition, but still were rather different. Aelfric himself considered the translation to be a separate rhetoric device as the text converted into a different language does not only carry the message to the target audience, but makes the process of communication easier. For Wulfstan the message itself is of importance, not the source, so he elaborated his unique style of communicating his ideas to the target audience. The practical and scientific value of the article is expressed in the need to structure the existing studies of the influence of the Latin language on Old English and opens up the perspective of further study in the field of rhetoric and pragmalinguistics.

Three-dimensional Euler grid approximation method for multi-droplet motions in the steam-water separator

Motions of multi-droplets in steam flow are a common and important phenomenon in various fields such as the environment, chemical industry, and energy. To simulate the motion of multiple droplets, a three-dimensional Euler grid approximation method, which applies to structured and unstructured grids, was proposed. Criteria were established to ensure that the motion of droplets is restricted to the grid nodes without compromising accuracy. The method is capable of updating the information of multiple droplets at each calculation step for all nodes and obtaining distribution information including droplet density and velocity. The multi-droplet motions in the steam separator were simulated and velocity field of multi-droplets showed a symmetrical distribution. The multi-droplet motions process in the swirl vane separator of the steam-water separator was also simulated. The results demonstrated that under the studied operating conditions, the critical droplet radius that can be separated by the steam-water separator was 40 μm. The specific positions of droplet-wall collisions were mainly concentrated on the blades and outer wall of the swirl-vane separator, as well as the inner cylinder. The model may serve as a dependable guide for the optimal solution of separation device structures and simulating various other multi-droplet motion processes.

P‐BT‐19 | Red Cell Reduction of ABO Incompatible Bone Marrow Transplant Cells with Automated Separation Device

P‐BT‐19 | Red Cell Reduction of ABO Incompatible Bone Marrow Transplant Cells with Automated Separation Device

Incorporation of a Morphologically Controlled Ice Grain Boundary into a Microfluidic Device for Size-Selective Separation of Micro/Nanospheres.

A frozen aqueous solution was integrated into a microfluidic device as a size-tunable separation field for the size-selective separation of micro/nanospheres. The width of the ice grain boundaries formed in frozen aqueous solutions could be altered by controlling the operating temperature. A freezing chamber was placed adjacent to the microfluidic channel. A sample-dispersing aqueous sucrose solution was injected into the chamber and frozen, allowing the freeze-concentrated solution (FCS) to run vertically to the microfluidic channel, where the eluting solution flows. The operating temperature can be used to control the physical interaction between the ice wall and micro/nanospheres, enabling size-selective migration. The eluted micro/nanospheres in the microchannel were passed through the eluting solution collected from the outlet. We achieved size-selective separation and collection of microspheres and nanospheres. We separated the exosomes and yeast cells to demonstrate their applicability in bioseparation. The present method is suitable not only for size-selective separation but also for evaluating the biological expression of extracellular vesicles under cryogenic conditions.

Supercapacitive Swing Adsorption of Carbon Dioxide: Current Status and Perspectives

AbstractSupercapacitive swing adsorption (SSA) is a newly discovered electrochemically driven carbon dioxide capture method using the principle of electric double‐layer capacitor, which achieves the purpose of adsorption and desorption of CO2 by charging and discharging the supercapacitive electrodes. Based on this method, gas separation devices were designed which could adsorb CO2 from a mixture of carbon dioxide and nitrogen, and a series of factors affecting the CO2 adsorption capacity were explored. This review briefly introduces the SSA mechanism and the structural design of SSA modules, and analyzes the factors influencing the performance of SSA from multiple aspects, with emphasis on electrode materials, in order to find ways to improve the CO2 adsorption capacity of SSA modules.