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Inspired by the viscoelastic displacement theory, we have developed a product called preformed particle gel (PPG) as conformance control agent to enhance oil recovery and control excess water production. The migration law of PPG suspension in porous media is related to its deep profile control and displacement capability. Laboratory experiments indicate that PPG suspension has good viscosity increasing, and the apparent viscosity decreases with the increase of shear rate. PPG suspension is mainly elastic, and its network structure makes it have certain shear stability. PPG particles realize migration in porous media in the way of “accumulation and blockage→pressure increase→deformation and migration”. When the ratio of the PPG particle size to the pore throat diameter δ ranges from 35.52 to 53.38, the particles can match through the porous medium. When the permeability difference of the parallel model is 5, PPG suspension has the highest profile improvement rate, 69.10%. PPG suspension can adjust the planar heterogeneity, and increase the oil recovery rate by 20.75%. The PPG suspension can effectively start “cluster"、 “film” and “blind end residual oil”, and has a high oil washing efficiency. The core NMR T2 spectrum shows that PPG suspension mainly reduces oil saturation in mesopores and macropores. After PPG flooding, the EOR capacity of small pores is the highest, 39.11%.

We investigated the solid–liquid suspension characteristics in the tank with a liquid height/tank diameter ratio of 1.5 stirred by a novel long-short blades (LSB) impeller by the Euler granular flow model coupled with the standard k–e turbulence model. After validation of the local solid holdup by experiments, numerical predictions have been successfully used to explain the influences of impeller rotating speed, particle density, particle size, liquid viscosity and initial solid loading on the solid suspension behavior, i.e. smaller particles with lower density are more likely to be suspended evenly in the liquid with higher liquid viscosity. At a low impeller rotating speed (N), increase in N leads to an obvious improvement in the solid distribution homogeneity. Moreover, the proposed LSB impeller has obvious advantages in the uniform distribution of the solid particles compared with single Rushton turbine (RT), dual RT impellers or CBY hydrofoil impeller under the same power consumption.

This investigation aims to study a novel biologically derived coating applied on Ti alloy substrates. Obtained from a low-cost fish bone resource, a nanocrystalline hydroxyapatite has been synthesized and converted to an organic suspension. Coating was then manufactured by a high-velocity suspension flame spray process. The microstructure, phase composition, coating thickness, and roughness of hydroxyapatite (HA)-coated samples were studied. The results indicated the presence of both hydroxyapatite and β-tricalcium phosphate phases and the final coating layer was uniform and dense. In vitro bioactivity and biodegradability of the HA/Ti composite samples were estimated by immersion in simulated body fluid. Remarkable reductions in Ca2+ and PO43- ion concentrations were observed as well as low weight loss percentage and a slight variation in the pH value, indicating the generation of an apatite layer on the surface of all studied samples. Scanning electron microscopy, energy-dispersive x-ray analysis, and inductively coupled plasma–optical emission spectrometry confirm these results. Thus biological derived HA coatings are a promising candidate to enhance bioactivity and biodegradability of bone implants. To demonstrate feasibility on commercial medical components, a medical screw was coated and evaluated., Science & Technology Development Fund (STDF), Projekt DEAL

In this paper, afull-car prototype of the recently proposed mechatronic suspension, Series Active Variable Geometry Suspension (SAVGS), is developed for on-road driving experimental proof of concept, aiming to be adopted by suspension OEMs (original equipment manufacturers) as an alternative solution to fully active suspensions. Particularly, mechanical modifications are performed to both corners of the front double-wishbone suspensionof a production car, with active single-links attached to the upper-ends of the spring-damper units, while both corners of the rear suspension remain inthe original (passive) configurations.The mechanical modifications involve innovatively designed parts to enable the desired suspension performance improvements, while maintaining ride harshness at conventional levels.Areal-time embedded system is further developed to primarily implement:1) power supply, data acquisition and measurementsof the vehicle dynamics related variables, and 2) robust control application for the ride comfort and road holding enhancement, which is based on a derived linearized model of the full-car dynamics and a newly synthesizedH-infinity control scheme. Results obtained from on-road driving experiments are inessential agreement with numerical simulation results also produced. Overall, the full-car prototypeof SAVGS demonstrates promising suspension performance,with anaverage 3 dB attenuation (or equivalently 30% reduction) of the chassis vertical acceleration at aroundthe human-sensitive frequencies (2-5Hz),as compared to the original vehicle with the passive suspension system. More importantly, the prototype also indicatesthe practicality of the solution, as the SAVGS retrofit to a real car is achieved by simple mechanical modifications, compact actuator packaging, smallmass increment(21.5kg increase with respect to the original vehicle), limited power usage (an average value of 134W in DC batteries with a Class D random road) and acceptable economic cost.

The coaxial mixers enhance the suspension of concentrated slurries in an agitated reactor. In this research work, the complex slurry suspension and dissemination behavior in a coaxial slurry mixing system (comprised of a close clearance anchor rotating with a low speed and an inner axial impeller rotating with a high speed) was analyzed employing ERT (electrical resistance tomography, a non-intrusive flow visualization technique), and computational fluid dynamics (CFD). The numerical models were validated by comparing the axial solid concentration profiles generated using the ERT data and the CFD simulation results. The influences of various important parameters such as the diameter of the inner axial impeller, the inner impeller type, and the inner impeller spacing on the hydrodynamic characteristics of the slurry suspensions in a coaxial mixing vessel were thoroughly analyzed. The radial and axial velocity profiles of solid particles were generated using the validated mathematical models. The assessment of energy loss due to the solid–solid collisions, the particle–fluid frictions, and the particle–vessel wall collisions was conducted. The evaluation of optimum inner impeller clearance and inner impeller diameter is essential to attain a high degree of solids suspension and dissemination in a coaxial slurry mixing system.

The electromagnetic suspension system (EMSS) plays a critical role in providing attractive force for middle-low-speed maglev trains, which contains two critical components– an electromagnet and a steel track. However, with the acceleration of trains, the eddy current generated by the relative motion between the electromagnet and the track becomes intensified, which may directly weaken the attractive force. To maintain the suspension airgap between the iron yoke and the track stable, more current needs to be inserted into the winding of the electromagnet. The local thermal surge existing in the winding may appear due to the overloaded input current for long term, which may cause the insulation aging or even damage of the winding. If the short circuit accident occurs between the neighboring turns of the winding due to the inter-turn insulating damage of the winding, the loss of suspension force tends to be deteriorated undoubtedly. In this paper, a novel hybrid suspension system mixed electromagnetic and permanent magnetic modes is proposed for enhancing suspension force with economical power consumption. But, when applying permanent magnets for assisting electromagnets, the firm absorption (FA) phenomenon needs to be considered. Two suspension schemes with unequal-width and unequal-height iron yokes are launched for reducing FA risk. The corresponding FEM models have been built and verified by experimental results. The comparison of different suspension schemes under dynamic condition with different relative velocity between the suspension module and the track has been undertaken in the end.

Al2O3 coatings were prepared by atmospheric plasma spraying (APS) and suspension plasma spraying (SPS). The microstructure, phase composition and nano-hardness of the two coatings were tested. Meanwhile, the friction and wear performance of SPS and APS in different environments were systematically studied. The results showed that both coatings exhibited a stable friction state and low wear rate under different environments. The special fine structure and high hardness value of SPS coating made its wear resistance much higher than that of APS coating. Additionally, the wear mechanisms of the two coatings in dry sliding friction were mainly abrasive wear, fatigue wear and adhesive wear. The APS coating had slight abrasion, while the SPS coating exhibited a negative abrasion state, in the seawater environment.

The goal of the research was to investigate the profile control and oil displacement characteristics of the polymer nanoparticles after high temperature swelling. The displacement parameters showed considerable influence on the plugging effect of the high-temperature swelled polymer nanoparticles, such as the core permeability, concentration of nanoparticles in the suspension, swelling time and swelling temperature, which makes it flexible to control the plugging effect by controlling displacement experiments conditions. Experimental results show that polymer nanoparticles dispersion system with a concentration of 500 mg/L is suitable for cores plugging with a permeability of 30 × 10−3 - 150 × 10−3 μm2, even after aging at 150 °C for three months. The shunt flow experiments show that when the displacement factors are optimal values, the polymer nanoparticles after high temperature swelling to plug the high-permeability layer selectivity and almost do not clog the low-permeability layer. Oil recovery of homogeneous artificial core displacement experiment and a heterogeneous double-tube cores model are increased by 20% and 10.4% on the basis of water flooding. The polymer nanoparticles can be a great help for petroleum engineers to better apply this deep profile control and flooding technology.

Digital light processing (DLP) is one of the most important additive manufacture technologies to fabricate ceramic parts with complex geometries. Compared with pure photosensitive resin, the cure performance of ceramic suspensions is obviously different due to the optical property change after the addition of ceramic powders. In this paper, a unique oxidation process was used to modify the optical properties of nitride powders including AlN and Si3N4. The properties of oxidized ceramics were investigated and the cure performance of ceramic suspensions was then characterized. The effect of oxidation time on cure performance was evaluated. The results showed that for AlN, oxidation process leads to the smaller cure depth and smaller excess cure width as compared with non-oxidized AlN and for Si3N4, oxidation process leads to the larger cure depth and larger excess cure width as compared with non-oxidized Si3N4, indicating that both refractive index and light absorbance of ceramic powders have obvious effects on cure behaviors. Additionally, the cure behavior of oxidized ceramic suspension in this study shows that the relationship of cure depth vs. incident energy agrees well with Beer- Lambert model, but the excess cure width vs. incident energy is not consistent with quasi Beer-Lambert model due to the nature of digital micromirror device (DMD).

Overhead conductors for transmission lines are subjected to cyclic loading due to Aeolian vibration which can lead to the failure of their wires. One of the most critical transmission power line points where fatigue failure occurs is the vicinity of the assembly consisting of the conductor and the suspension clamp. This work evaluates the fatigue life of assemblies made by two types of conductors, i.e. All Aluminium Alloy Conductor (AAAC) 1120 and 6201. Furthermore, metallic and elastomeric clamps are examined. Based on the generated S-N and fymax-N graphs, it was proved that the assembly AAAC 1120 with elastomeric clamp presented a better fatigue performance than the other three assemblies. Additionally, the change in fatigue life was investigated, failure and contact marks analyses were also performed on all samples after fatigue test with respect to the conductor layer where the failure occurred as well as the types of break and the position of wires break (whether radial and longitudinal position).

By surface modification with APTMS, spontaneous coagulation casting (SCC) of fused silica based on Isobam was achieved and the possible coagulation and molding mechanism is proposed. Through the interaction between the polar groups on the Isobam molecular chain and the incorporated –NH2 groups on the surface of the silica particles, Isobam molecular chains were adsorbed on the surface of particles, which initiate the formation of flocs and the solidification of the suspension. The addition of dispersant TMAH results in the hydrolyzation of Isobam, forming more –COO–, which effectively improves the fluidity and stability of the suspension. Then the zeta potential, rheological properties and coagulation behavior of the suspension were systematically investigated and the fused silica suspension with high solid content (up to 52 vol%), low viscosity and good coagulation properties were prepared at 1.8 wt% TMAH and 0.5 wt% Isobam dosage. After sintering at 1260 °C for 4 hours, the fused silica ceramics (50 vol% solid content) shows a high bending strength of 61.59 MPa, the lowest dielectric loss tanδ of 8.46 × 10-4 and the dielectric constant of 3.72. Thus, this work provides a simple and effective method for preparing fused silica and other ceramics with negative surface charge by Isobam SCC.

Erosion may be defined as the destruction of a material by abrasive action of a liquid or gas. The wearing away is purely mechanical with no electro-chemical reaction. This process occurs on surfaces, pipelines wherever the flow of liquid along with particles in suspension causes erosion. In this investigation, the erosion rate on a coated surface was studied using pot erosion tester. The substrate material used was stainless steel of grade 316. The material was machined to the required dimensions and was coated one set with tungsten carbide- cobalt and another set with alumina. The coating was done using a detonation spray process. The specimens were weighed before and after the testing. The mass loss and erosion wear rate were calculated. It was found that the erosion wear rate was minimum when the speed of rotation was 3 m/ sec and increases as the speed increases. The SEM examination revealed the formation of flake type debris due to the interaction between the erodent and the specimen.

In this study, we have carried out experiments to characterize the wall slip of colloidal suspensions of kaolinites. To demonstrate slip, the rheological measurements were carried out with parallel-plate geometry with smooth and rough plates. The asperities of the rough surface penetrated the slip layer and created a nearly no-slip region, whereas the smooth plate showed significantly higher slip, a conclusion drawn by comparing the macroscopic flow curves in both cases. Two slip regimes were identified, namely, (i) an elastic slip regime below the yield stress of the suspension where the material slips like a solid and (ii) a slip regime above the yield stress where the material yields and flows. The slip velocity was quantified using a simple phenomenological slip model that seems to capture slip in both flow regimes. The transition from the first slip regime to the other has been resolved numerically as the material starts yielding first at the edge of the parallel-plate geometry with the yield point propagating inwards as the rotational speed is increased. The numerical method also establishes uniquely the yield stress value, which was found to agree with data obtained from parallel-plate, cone-and-plate, and concentric cylinder geometries.

In this paper, the pressure drop influencing parameters in slurry pipeline have been optimized by using Taguchi’s approach. S/N ratios were calculated by orthogonal array L16 (42) and characterized by using smaller-the-better rule. Pressure drop experimental were conducted on pilot plant test loop having 50 mm diameter. Pressure drop of fly ash slurry was measured with addition of coarser bottom ash at different solid concentrations and flow velocities. The bottom ash addition reduced the pressure drop of fly ash slurry in pipeline and pressure drop increases with the increase in the flow velocity. Flow velocity is the most influencing parameter as compare to the other parameters. The rheological charactertrics of fly ash slurry is also studied with and without addition of bottom ash in order to transport the high solid concentration of fly ash slurry in a pipeline. Apparent viscosity of fly ash slurry suspension with 10, 20 and 30% addition of bottom ash indicates that apparent viscosity of fly ash slurry decreases with the addition of bottom ash due to the presence of coarser bottom ash in fly ash finer particle suspension. The apparent viscosity plays a vibrant role on pressure characteristics of fly ash slurry transportation.

Porous materials manufactured by freeze-casting are demonstrating potential application as oxygen carriers for the production and purification of hydrogen, or anode material for lithium-ion batteries. However, to obtain the required pore morphology and sufficient mechanical strength, the suspension processing parameters must be controlled. Fe2O3 nanoparticles/camphene suspensions were fabricated using stearic acid as the dispersant agent showing a low-viscosity (130 mPa·s) with a high solid volume fraction (0.3). Suspensions show a shear-thinning behavior according to the Sisko model and a maximum packing fraction of 0.569 estimated from a zero porosity sample. A modified Krieger and Dougherty model was introduced to incorporate the influence of the particle-aspect ratio. The Fe2O3 scaffolds manufactured by freeze-casting shown a gradient pore size along the freezing direction, which was diminished with the solid volume fraction, the compression strength was improved with the pore size reduction and fitted according to the minimum solid area model.

Carbon nanotubes (CNTs) have exhibited immense potential for applications in biology and medicine, and once their intended purpose is fulfilled, the elimination of residual CNTs is essential to avoid negative effects. In this study, we demonstrated the effective collection and simple removal of CNTs dispersed in a suspension via thermal convection. First, a tapered fiber tip with a cone angle and end diameter of 10° and 3 μm, respectively, was fabricated via a heating and pulling method. Further, a laser beam with a power and wavelength of 100 mW and 1.55 μm, respectively, was launched into the tapered fiber tip, which was placed in a CNT suspension, resulting in the formation of a microbubble on the fiber tip. The temperature gradient on the microbubble and suspension surface induced thermal convection in the suspension, which resulted in the accumulation of CNTs on the fiber tip. The experimentally formed CNT cluster possessed a circular top surface with a diameter of 87 μm and an arched cross-section with a height of 19 μm. Furthermore, this CNT cluster was firmly attached to the fiber tip. Therefore, the removal of CNT clusters can be realized by simply removing the fiber tip from the suspension. Moreover, we simulated the thermal convection that caused CNT aggregation. The obtained results indicate that convection near the fiber tip flows toward it, which pushes the CNTs toward the fiber tip and enables their attachment to it. Further, the flow velocity is symmetrically distributed as a Gaussian function, which results in the formation of a circular top surface and arched cross-sectional profile for the CNT cluster. Our method may be applied in biomedicine for the collection and removal of nano-drug residues.

Functionally graded materials (FGMs) play an essential role in tissue engineering because of their satisfactory histocompatibility and excellent mechanical performance. While traditional manufacturing methods allow production of simple FGMs, precise control of composition and customized property at transition between the dissimilar materials is still a challenge. Here, an extrusion-based functionally graded additive manufacturing (FGAM) platform was developed to generate smooth graded parts by thrusting out monolithic cylindrical filaments with high viscosity. Furthermore, the rheological properties, hydrodynamic behavior, and mixed homogeneity of the non-Newtonian fluids were studied. Therefore, the appropriate solid contents, alternative energy-efficient mixers, and optimized printing parameters were proved to be beneficial for an outstanding deposition effect of the suspension. Ultimately, an object with smooth gradient was successfully manufactured. The validity of this strategy was verified via optical microscopy combined with an image processing method to gauge homogeneity and a scanning electron microscope to investigate graded composition and microstructure.

Microfluidic devices with superior microscale fluid manipulation ability and large integration flexibility offer great advantages of high throughput, parallelisation and multifunctional automation. Such features have been extensively utilised to facilitate cell culture processes such as cell capturing and culturing under controllable and monitored conditions for cell‐based assays. Incorporating functional components and microfabricated configurations offered different levels of fluid control and cell manipulation strategies to meet diverse culture demands. This review will discuss the advances of single‐phase flow and droplet‐based integrated microfluidic suspension cell culture systems and their applications for accelerated bioprocess development, high‐throughput cell selection, drug screening and scientific research to insight cell biology. Challenges and future prospects for this dynamically developing field are also highlighted.

In order to develop a highly efficient, simple-preparation and renewable explosion suppressant of composite powders, the superfine NaHCO3-shell powder (S-S) composite explosion suppressant was prepared by one-step method with airflow crusher to fulfill the mechanical dry coating of shell powder by NaHCO3, which solved the contradiction between dispersion and suspension force of explosion suppressant particles. The composition optimization and performance test of S-S composite explosion suppressant were carried out with the use of 20 L explosion tank and large tubular coal dust characteristics identification instrument. The results show that when the shell powder particles are coated with NaHCO3, the overall water absorption performance of the powder is reduced, the particle agglomeration phenomenon is weakened, and the dispersion is obviously improved. With the increase of NaHCO3 ratio, the ignition sensitivity of coal dust decreases, and the time to reach the first explosion Pmax is gradually delayed, and both Pmax and (dP/dt)max decrease. With the following explanations: NaHCO3 has a significant effect on reducing (dP/dt)max due to its chemical reaction, while shell powder is beneficial to reducing the Pmax due to its physical barrier effect. The suppression effect of S-S composite explosion suppressant on coal dust explosion is far better than that of pure NaHCO3 or shell powder.

Proppant is a key material for enhancing unconventional oil and gas production which requires a long distance of migration and efficient liquid conductivity paths within the hydraulic fracture. However, it is difficult to find a proppant with both high self-suspension ability and liquid conductivity. Here, a simple method is developed to coat epoxy resin onto the ceramic proppant and fabricate a novel coated proppant with high hydrophobicity, self-suspension, and liquid conductivity performance. Compared with uncoated ceramic proppants, the epoxy resin coated (ERC) proppant has a high self-suspension ability nearly 16 times that of the uncoated proppants. Besides, the hydrophobic property and the liquid conductivity of the ERC proppant increased by 83.8% and 16.71%, respectively, compared with the uncoated proppants. In summary, this novel ERC proppant provides new insights into the design of functional proppants, which are expected to be applied to oil and gas production.

Effective methods for rapid sorting of cells according to their viability are critical in T-cells based therapies to prevent any risk to patients. In this context, we present a novel microfluidic device that continuously separates viable and non-viable T-cells according to their dielectric properties. A dielectrophoresis (DEP) force is generated by an array of castellated microelectrodes embedded into a microfluidic channel with a single inlet and two outlets; cells subjected to positive DEP forces are drawn towards the electrodes array and leave from the top outlet, those subjected to negative DEP forces are repelled away from the electrodes and leave from the bottom outlet. Computational fluid dynamics is used to predict the device separation efficacy, according to the applied alternative current (AC) frequency, at which the cells move from/to a negative/positive DEP region and the ionic strength of thesuspension medium. The model is used to support the design of the operational conditions, confirming a separation efficiency, in terms of purity, of 96% under an applied AC frequency of 1.5 × 106 Hz and a flow rate of 20 µl/h. This work represents the first example of effective continuous sorting of viable and non-viable human T-cells in a single-inlet microfluidic chip, paving the way for lab-on-a-chip applications at the point of need.

To improve the efficiency of cable force adjustment of composite saddle anchor span of single-tower single-span ground-anchored suspension bridge, a strain incremental adjustment method is proposed. The analytical calculation model is established according to the relative spatial position of the cable strand and the saddle groove of the composite saddle, and the target cable force of the cable strands is calculated by the target position of the composite saddle in the cable-stayed bridge and construction phases. Considering the coupling relationship between the cable strand and the composite saddle, the calculation formula of the change in main span main cable force and anchor span cable force after the adjustment of a single cable strand is derived. Based on the condition of equilibrium of forces along the slip surface of the composite saddle, the slip amount of composite saddle after a round of cable strand adjustment is obtained, then the adjustment amount of actual construction of the cable strands is also obtained through the strain incremental adjustment method. With the help of a numerical simulation platform, the calculation program of the cable force adjustment of composite saddle anchor span is established by an iterative solution method. In this paper, taking the Jinsha River Bridge at Hutiao Gorge as a research object, the adjustment of cable force of composite saddle anchor span is analyzed and calculated. The research results indicate that the calculated cable force is obtained by the strain incremental adjustment method, and it is similar to the measured cable force. The cable strand adjustment and optimization method avoids excessive repeated stretching and relaxation of a single cable strand in the process of multiple rounds of cable strand adjustment and reduces the amount of construction adjustment. This method can effectively reduce the times of cable strand adjustment and improve the efficiency of adjusting the anchor span cable force.

In this work, a novel spring suspension strut with quasi-zero-stiffness (QZS) and zero-stiffness (ZS) properties is proposed to improve the performance of the multi-directional micro-vibration isolator. The QZS and ZS properties are achieved by developing a hexagon structure with negative stiffness mechanism to counteract the positive stiffness of a vertical suspension spring. The strut also has high loading capacity and excellent equilibrium stability. Based on the Stewart platform, the spring suspension strut can largely lower the isolation frequency in all 6-degrees-of-freedom (6DOFs), while the effectiveness of micro-vibration isolator is notably improved. The effects of nonlinearity on the stability, equivalent cross-coupling force and vibration response are discussed in detail. The design concept of the spring suspension strut is first proposed, and the static modeling is conducted. Then, by using such struts as supporting mounts, a 6DOFs micro-vibration isolator is achieved, and the equivalent cross-coupling force and stiffness of the isolator are analyzed. Furthermore, the equations of motion of the isolator are established by the Hamilton principle. The frequency response characteristics particularly for force transmissibility of the platform are obtained to achieve the parameter optimization for maximum frequency band of isolation. Finally, compared with the linear counterpart, the 6DOFs QZS and ZS micro-vibration isolator has broader bandwidth of isolation starting from lower frequency and possesses higher effectiveness in ultra-low-frequency range. The results presented herein provide an insight of dynamics into the QZS and ZS mechanisms for their application in multi-directional vibration engineering.

The adverse reactions caused by 6-thioguanine (6-TG) in anti-cancer treatment are closely related to the dose, leading to the urgent need for clinical monitoring of its concentration. In this work, a highly reproducible free-standing liquid membrane (FLM) surface-enhanced Raman spectroscopy (SERS) substrate was developed to detect 6-TG in human urine and serum quantitatively. Briefly, a prepared sample was adjusted to pH 2 and mixed with concentrated core–shell bimetallic nanoparticle (AgcoreAushell NP) suspension. The Au/Ag ratio of the AgcoreAushell NPs was optimized. Then the mixture was formed into an FLM using a custom mold. The relative standard deviation (RSD) of the experimental results can be stabilized below 10% (n ≥ 10). The R2 of the calibration curve in the range of 10 ~ 100 μg kg−1 was 0.988. In addition, the limit of detection (LOD) (3σ/k) of 6-TG was 5 μg kg−1. The FLM SERS platform has been successfully applied to the rapid and reliable analysis of 6-TG spiked in body fluids.

In this paper, the dynamics of the vehicle suspension system under the random excitation and the periodic excitation are investigated. To improve the damping performance of the vehicle suspension system, a two stage ISD suspension with “Inerter-Spring-Damper” in each stage is proposed based on electromechanical similarity theory. A vehicle dynamic model with two stage ISD suspension is established in this paper. The dynamic equation is solved by the Runge-Kutta method and the dynamic response of the whole vehicle system is obtained. Taking the traditional suspension as the comparison object, the dynamic characteristics of the system under random excitation and periodic excitation are studied in the time domain, and the suppression effect of the suspension designed in this paper on the resonance peak is verified in the frequency domain. The influence of the inertia coefficient on the damping performance of the vehicle suspension system is analyzed. The effects of excitation amplitude and vehicle speed on ride comfort improvement of vehicle system with two stage ISD suspension are discussed respectively. The results show that, the resonance peak values of body acceleration, dynamic travel of rear suspension and rear tire dynamic load frequency response are reduced by 59.1%, 21.6%, and 60.3% respectively. With the increase of excitation amplitude in the range of 0.02–0.04 m, the ride comfort improvement of two stage ISD suspension system is always more than 61%. With the increase of vehicle speed in the range of 10–25m/s, the performance improvement rate of two stage ISD suspension system can reach more than 34.1%.

An electroassisted filtration technique has been employed to improve dewatering of a suspension of microfibrillated cellulose (MFC) produced via 2,2,6,6-tetramethylpiperidinyl-1-oxyl (TEMPO)-mediat...

This work was supported by Edith Cowan University (ECU), Australia, Early Career Research Grant No. G1003450. The authors would like to thank ECU, Australia, for the Ph.D. grant vide ECU HDR Scholarship-2018.

The corrosion environment of a steel truss bridge significantly shortens its service life, particularly the chemical pollution in the air. A linear corrosion prediction model is proposed based on Miner’s linear cumulative damage concept to solve the difficulty of implementing accelerated corrosion tests. Moreover, an equivalent fatigue test is designed in combination with the corrosion prediction model. The results indicate that the bridge’s fatigue resistance can meet the design requirements when the corrosion environment is not considered. When the corrosion effects are jointly considered, the fatigue durability of the bridge is insufficient. With the increase in fatigue cycles, stiffness degradation presents a three-stage trend. The intermediate stage is a gentle development stage from the fatigue test results, accounting for approximately 80% of the total life cycles. Finally, a fatigue damage prediction model considering corrosion factors is established, and the law of fatigue damage and stiffness degradation of the structure under a corrosive environment is determined.

As an alternative reductant for fossil fuel in the future, straw-type biomass contributes to emission reduction and green utilization in the suspension roasting process. In this study, the influences of the roasting time, roasting temperature and dose of straw-type biomass after suspension magnetization roasting (SMR) and separation were investigated. The optimal conditions were determined to be a roasting time of 7.5 min with a straw-type biomass dose of 20 wt% and a roasting temperature of 800 ℃, in which an iron grade of 71.07% and recovery of 94.17% were obtained for the iron concentrate. The maximum saturation magnetization under optimal conditions was 35.05 A·m2·g−1, and the gaseous regulation of the biomass revealed that cumulative reducing gas volume was 293.93 mL at the optimal roasting time of 450 s. The transformation of hematite to magnetite was detected by X-ray diffraction (XRD). During microstructure evolution, the outer layer consisting of fissures and tiny holes continuously deepened toward the core.

Taking regolith samples by unmanned equipment is a popular method to understand the outerspace in aerospace exploration. The electrostatic sampler can drive the charged particles to move or be transported by strong electric intensity, and its driving ability is extraordinarily powerful in the low gravity environment. The amount of charge acquired by a particle is vital to understand its dynamic behaviour in an electric field. In this study, the model of contact charging for a single particle is discussed to present its detailed behaviour during its charging process. Further, a suspension balancing method (SBM) is proposed for measuring the charges of a single particle. The experimental result fits well with the amended single-particle charging model. The experimental and simulation results prove that the charging source of a particle dynamically approaching the electrode can be attributed not only to the contact electrification but also to the air discharge.

During continuous casting of steel billets, mould lubrication is provided by addition of oil in case of open casting and mould powder is used during close casting. Open casting of steel billets has hazards like mould spitting of liquid metal whereas in case of close casting the sequence length is less incurring more refractory consumption. To get combined advantages of both, a new class of lubricant has been developed by dispersing mould powder in oil using nonionic dispersants. The characteristics of this suspension are studied extensively to evaluate all required properties for plant operation. The result of plant studies shows, (1) reduction in liquid metal spitting by 60% and thence reducing hanger breakout, (2) heat extraction in the mould is reduced by 14% and (3) no entrapment of mould powder found in the billet. This can be used as an alternative to close casting and hence increasing sequence length.

Heat generation and serious energy consumption of normal-conductive suspension electromagnets influence the performance and stability of suspension systems. With the development of second generation (2G) high temperature superconducting (HTS) technologies, HTS suspension electromagnets are being considered for energy saving purpose. In this paper, a suspension system with three suspension electromagnets is designed, which is comprised of two normal-conductive suspension electromagnets and a 2G-HTS suspension electromagnet. A three-dimensional (3D) electromagnetic field simulation based on finite element method (FEM) is carried out, and the force test platform of suspension electromagnet is built for performance evaluation of the HTS suspension electromagnet. The experimental results show that the current of HTS suspension electromagnet is steady loaded from 0 A to 70 A under 77 K working conditions, with the suspension force meet the requirements. This work provides a certain theoretical and practical foundation for the future superconducting suspension projects.

Ventricular assist devices (VADs) which employ a maglev motor have significant advantages of high mechanical durability and better blood compatibility by eliminating mechanical contact for impeller suspension. In the last decade, research interest in maglev VADs for small pediatric patients is highly increased. However, drastic miniaturization of maglev motors has technical difficulties in deterioration of suspension stability and energy efficiency. Our group has developed an ultra-compact axial gap double stator self-bearing motor utilizing 5-degrees of freedom control for pediatric VADs to overcome the above technical drawbacks. In this article, feasibility of the proposed self-bearing concept for stable impeller suspension was verified, as well as enhancement of energy efficiency of the developed self-bearing motor was investigated by modifying motor core material and winding design. In pump operation with the modified motor, noncontact impeller suspension with energy input of 3.2–5.2 W over a range of pediatric circulatory support (4000–5000 r/mim) was demonstrated.

Electrophoretic deposition (EPD) has been investigated extensively as an efficient and straightforward surface coating approach to enhance corrosion resistance, biocompatibility, bioactivity, wear resistance, anti-microbial qualities, and mechanical properties of magnesium (Mg) and its alloys. Here, we provide a comprehensive review of EPD coatings for Mg alloys. Reported works are classified based on the nanoparticles used in the suspension, composite coating strategies, combined fabrication approaches, and application domains. Future scopes of research also presented.

Design of Radial Passive Magnetic Bearings with Active Dampers (Radial PMB-AD) and their application in a down-hole natural gas compressor (DHGC) are discussed. These compact and reliable bearings allowed non-contact suspension of a high-speed DHGC rotor spinning at 50kRPM in a highly adverse environment more than 3km (10,000 ft) below the ground with temperatures reaching 100 degrees C. The design was further complicated by the space limitations imposed by a well casing. The paper presents the design of PMB-AD modules, as well as their integration and testing as a part of a DHGC.

U-type reduction chamber plays a significant role in the suspension roaster which has been proven to be one of the most highly efficient and clean magnetization equipment to utilize complex refractory iron ores. In the present work, a hydrodynamic model has been developed for the operation that the materials in the fluidization chamber are fluidized while the particles in the supply chamber are in a moving packed bed. Through fluid dynamic analysis, a hydrodynamic model including four equations has been established, whose solution results in the solids concentration in the fluidization chamber and materials' height in the supply chamber. Meanwhile, the effects of operating conditions such as fluidizing gas velocity and delivery rate on solids concentration in the fluidization chamber and materials' height in the supply chamber were studied by a combination of model analysis and experiments. The experiments were carried out in a U-type reduction chamber cold test apparatus with alumina particles. The model predictions showed good agreement with the experimental data, giving average errors below 6.28% and 4.96% respectively.

The paper addresses coupled loss and thermal analyses of a bearingless drive with an operating speed range of 17 00032 000 rpm. The drive is a part of a high-temperature heat pump system integrated in a high-speed compressor. This drive system comprises two bearingless motor units and an axial active magnetic bearing (AMB). The drive can be positioned horizontally or vertically. The positioning is directly related to the force necessary to raise and suspend the rotor. Furthermore, the amplitude of the suspension current has a significant effect on the motor winding and iron losses. The iron losses, eddy current losses in the magnets and losses in the bandage are investigated by 3D and 2D Finite Element Analysis (FEA). The influence of segmentation of the magnets on losses is analyzed. Friction losses of the coolant are calculated analytically, and all the losses obtained from the electromagnetic analysis are represented as distributed heat sources and coupled with the 3D thermal field analysis. The temperature fields are modelled under different motoring and suspension current conditions and evaluated for horizontal and vertical positions of the motor. As a precaution, demagnetization of the magnets is also considered.

Modification parts are found in Indonesia, one of which is suspension. This paper proves which after-market suspension has the best performance. These three suspensions were tested with a transient response with a test instrument that has an excitation height of 30 mm with a shaft rotational speed of 322 rpm. The observed responses are displacement and settling time. The test results without the addition of mass obtained a displacement of 25 mm for Aspira, 39 mm for AHM and 39 mm for Combiz. The addition of 30 kg mass resulted in 29 mm for Aspira, 38 mm for AHM and 23 mm for Combiz. Settling time without adding mass 1 s for Aspira and 1.2 s for AHM and 0.9 s for Combiz. With the addition of 30 kg mass obtained settling time of 1.3 s for Aspira, 1 s for AHM and 0.7 s for Combiz.

This paper deals with the analysis of unsteady flow and heat transfer of second-order fluid with fluid-particle suspension in a vertical channel in the presence of transverse magnetic field with viscous dissipation. The fluid is driven by a constant pressure gradient. The governing partial differential equations are converted in to ordinary differential equation by similarity transformation and solved analytically. The expressions for velocity, temperature, skin friction and heat transfer are obtained. The numerical results depicting the effects of visco-elasticity in combination with other flow parameters involved in the problem are presented graphically and discussed qualitatively.

Bulk nanobubbles (BNBs) have attracted substantial interest from academia and industry owing to their peculiar properties and extensive potential applications. However, a scalable engineering method needs to be developed. Herein, we developed a nanobubble generator based on venturi-type recirculating hydrodynamic cavitation. The existence of nanobubbles produced by our generator was confirmed using physicochemical test methods, including the Tyndall effect, multiple freeze-thaw degassing experiments, and trace metal analysis. Subsequently, the effects of different operating parameters (circulation time and operating pressure) on bulk nanobubble production and properties, as well as their stability, were investigated. The results suggest that the characteristics of BNBs varied with the circulation time (5-20 min) and operating pressure (2-5 bar). However, all the particle size distribution of BNBs had a bimodal distribution with a mean diameter of 180-210 nm for the different circulation time and operating pressures. For example, by increasing the circulation time from 5 to 20 min, the peak value of size distribution decreased from 333/122 nm to 218/52 nm, and the average sample scattering signal count rate (Avg. Count Rate) increased from 133 to 303 Kcps. The evaluation of the stability of the BNBs formed for the circulation time of 15 min and the operating pressure of 3 bar showed that they could continue existence and stability in the suspension for 72 h. The study results might provide a valuable method for further investigation of industrial applications of venturi-type nanobubble generators.

A seat suspension contributes greatly to vehicle ride comfort as a result of direct contact with the human body. Friction in a seat suspension produces strong non-smooth nonlinearity in seat dynamics, which makes the simulation-based optimization on the seat suspension’s performance time-consuming. This study tries to address parameter optimization on a vehicle seat suspension with the friction force in an analytical approach. A two degrees of freedom model is firstly established for the human body-seat system with friction and subjected to bandlimited random excitation. The nonlinear model is converted into an equivalent linear model by using Gaussian linearization. The dynamic responses of the linear model have then derived analytically and validated by Monte Carlo simulations. Based on the analytical solution, a multi-objective optimization strategy is proposed for the seat suspension. The acceleration of the human body and the suspension travel are chosen as the objective indexes to evaluate seat performance. Simulation results show that the proposed optimization strategy is efficient, where a global optimum is guaranteed owing to the analytical expression of the objective function. The optimization approach taking advantage of model linearization can be applied to similar mechanical systems with friction.

Adding flow channel between main and annular chambers in same strut of roll-coupled Hydro-pneumatic Inter-connected Suspension (HIS) can effectively avoid the negative hydraulic pressure caused by the high damping factor of connected pipes under high velocity condition. This flow channel is usually closed in previous research in HIS area. In this study, the effect of orifice between main and annular chambers in same strut to the dynamic properties of HIS under the different road excitations is investigated by the established AMEsim half-car simulation model. The bounce and roll displacement/acceleration of the sprung mass are used to evaluate the dynamic properties of HIS. The results illustrate that (1) the added orifice can reduce the roll displacement/acceleration with slight influence on the vertical displacement/acceleration under the transient and road loop excitations; (2) the added orifice will not change the resonance frequency of the bounce and roll modes; (3) comparing with the traditional HIS design (without the added orifices), the maximum roll transmissibility can decrease 30.17% with 2.89% increase of the maximum vertical transmission for the added orifice with 2 mm2 area. Overall, the results suggest that the proper size of the orifices will significantly increase the roll-stability properties with slight effect on the bounce mode under the road excitations.