Journal articles: 'Suspension conditions'

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Kamizela, Tomasz, Mariusz Kowalczyk, and Małgorzata Worwąg. "Conditions for effective ultrasonic disintegration of activated sludge suspension." Journal of Civil Engineering, Environment and Architecture XXXII, no. 1/2015 (March 2015): 265–78. http://dx.doi.org/10.7862/rb.2015.18.

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Chernoburova, Olga, Mathieu Jenny, Sébastien Kiesgen De Richter, Maude Ferrari, and Akira Otsuki. "Dynamic Behavior of Dilute Bentonite Suspensions under Different Chemical Conditions Studied via Magnetic Resonance Imaging Velocimetry." Colloids and Interfaces 2, no. 4 (September 27, 2018): 41. http://dx.doi.org/10.3390/colloids2040041.

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This study investigates dilute aqueous suspensions of bentonite particles using magnetic resonance imaging (MRI) velocimetry. Four different chemical conditions are tested to investigate the influence of pH and type of monovalent electrolyte on the local rheological behavior of bentonite suspensions. The results indicate the shear banding in a dilute suspension of 0.1 vol.% solid due to the formation of a continuous three-dimensional particle network under a certain chemical environment (i.e., pH 4 in 1 × 10−2 M KNO3). This network is responsible for the existence of the yield stress in that dilute suspension. Structural changes induced by modification of suspensions’ chemistry are examined via scanning electron microscopy. A previously established method based on processing the torques acquired via conventional rheometric measurement is also applied as an alternative way to recover local flow information. Within the shear rate range covered by our MRI velocimetry, the results of both methods show good agreement. This study suggests that the existence of a master curve (or global flow curve) for dilute suspensions is dependent on the bentonite particle organization, which is influenced by the suspension chemistry and the previous flow history.

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Peng, Yucheng, and Brian Via. "The Effect of Cellulose Nanocrystal Suspension Treatment on Suspension Viscosity and Casted Film Property." Polymers 13, no. 13 (June 30, 2021): 2168. http://dx.doi.org/10.3390/polym13132168.

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Cellulose nanocrystals (CNCs) have attracted significant interest in different industrial sectors. Many applications have been developed and more are being explored. Pre-treatment of the suspension plays a critical role for different applications. In this study, different pre-treatment methods, including homogenization, ultrasonication, and mixing with a magnetic stirrer were applied to a CNC suspension. After treatment, the rheological behaviors of the treated CNC suspensions were characterized using a rotational viscometer. The treated suspensions were then used to cast films for characterization by ultraviolet-visible (UV-Vis) and Fourier transform near-infrared spectroscopy (FT-NIR). All the CNC suspensions demonstrated a shear thinning phenomena. Homogenization or ultrasonication significantly decreased the suspension viscosity compared with the suspension mixed by a magnetic stirrer. The viscosity of CNC suspension changed with time after treatment and settlement of treated CNC suspensions in room conditions increased the viscosity dramatically with time. Different UV and visible light interferences were observed for the CNC films generated from suspensions treated by different methods. The degree of crystallinity of the CNC films evaluated by FT-NIR showed that the film from suspension treated by homogenization and ultrasonication has the highest degree of crystallinity. Pre-treatments of CNC suspension affected the suspension viscosities and formed film properties.

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Jackson, Remonica, Paul Lewis, and Stacy D. Brown. "Comparative Stability of Compounded Omeprazole Suspension Versus Commercial Omeprazole Kit When Stored in Oral Syringes Under Refrigerated Conditions." Journal of Pharmacy Technology 36, no. 5 (June 26, 2020): 179–86. http://dx.doi.org/10.1177/8755122520935532.

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Background: Omeprazole is a proton pump inhibitor used to manage gastrointestinal disorders. Special populations may require omeprazole to be given as an oral suspension. Objective: The purpose of this project was to compare the stability of omeprazole in the FIRST kit product to a traditionally compounded omeprazole suspension, when stored in refrigerated unit-dosed syringes. NG tube delivery of the 2 products was also investigated. Methods: Five batches of compounded omeprazole oral suspension and 5 kits of FIRST-Omeprazole were prepared to an initial concentration of 2 mg/mL. Suspensions were aliquoted into 5-mL doses in clear plastic oral syringes, and stored at 2-8 °C. Syringes from each batch were analyzed at baseline and after 7, 14, 21, and 30 days for omeprazole potency using HPLC. To assess suitability for NG tube administration, 20 mL of each suspension were administered through NG tubes (8Fr, 10Fr, and 18Fr), and percent omeprazole recovery assessed. Results: The chemical potency remained within 90-110% for 14 days and 30 days for compounded samples and FIRST-Omeprazole samples, respectively. There was a statistically significant difference in initial concentration; 1.89 mg/mL versus 1.98 mg/mL for compounded and FIRST-Omeprazole, respectively. After 30 days, FIRST-Omeprazole demonstrated 97.20% API recovery. Neither suspension experienced statistically significant loss of potency following NG tube passage. Conclusion: FIRST-Omeprazole suspension may be stored in refrigerated clear luer-lock oral syringes for 30 days. Traditionally compounded omeprazole suspension should be used within 14 days. Both suspensions are suitable for NG tube administration.

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Li, Shidong, Yeap Hung Ng, Hon Chung Lau, Ole Torsæter, and Ludger P. Stubbs. "Experimental Investigation of Stability of Silica Nanoparticles at Reservoir Conditions for Enhanced Oil-Recovery Applications." Nanomaterials 10, no. 8 (August 4, 2020): 1522. http://dx.doi.org/10.3390/nano10081522.

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To be effective enhanced oil-recovery (EOR) agents, nanoparticles must be stable and be transported through a reservoir. However, the stability of a nanoparticle suspension at reservoir salinity and temperature is still a challenge and how it is affected by reservoir rocks and crude oils is not well understood. In this work, for the first time, the effect of several nanoparticle treatment approaches on the stability of silica nanoparticles at reservoir conditions (in the presence of reservoir rock and crude oil) was investigated for EOR applications. The stability of nanoparticle suspensions was screened in test tubes at 70 °C and 3.8 wt. % NaCl in the presence of reservoir rock and crude oil. Fumed silica nanoparticles in suspension with hydrochloric acid (HCl), polymer-modified fumed nanoparticles and amide-functionalized silica colloidal nanoparticles were studied. The size and pH of nanoparticle suspension in contact with rock samples were measured to determine the mechanism for stabilization or destabilization of nanoparticles. A turbidity scanner was used to quantify the stability of the nanoparticle suspension. Results showed that both HCl and polymer surface modification can improve nanoparticle stability under synthetic seawater salinity and 70 °C. Suspensions of polymer-modified nanoparticles were stable for months. It was found that pH is a key parameter influencing nanoparticle stability. Rock samples containing carbonate minerals destabilized unmodified nanoparticles. Crude oil had limited effect on nanoparticle stability. Some components of crude oil migrated into the aqueous phase consisting of amide-functionalized silica colloidal nanoparticles suspension. Nanoparticles modification or/and stabilizer are necessary for nanoparticle EOR application.

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Samchenko, Svetlana, Irina Kozlova, Оlga Zemskova, and Ekaterina Baskakova. "Influence of optimal conditions of ultrasonic dispersion on the stability of suspensions of finely ground slags." MATEC Web of Conferences 265 (2019): 01017. http://dx.doi.org/10.1051/matecconf/201926501017.

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The preparation in the jet mill of finely ground slag (FGS) from the waste of metallurgical production granulated blast-furnace slag, the obtaining of slag suspensions, and the behavior of FGS particles in an aqueous dispersion medium are considered in the paper. It was found that FGS particles in the suspension form micelles of two types with negative (micelle 1) and positive (micelle 2) charges of FGS surface. To increase the aggregative and sedimentation stability of FGS particles in suspensions, studies were carried out using ultrasonic dispersion. The results of investigations on the detection of optimal dispersion parameters for slag suspensions are presented. It was found that in the absence of temperature control, the process of coagulation of slag particles is accelerated and aggregative and sedimentation stability of suspensions of FGS is reduced. The slag particles in the suspension form aggregates that lead to a deterioration of the strength characteristics of the cement stone using suspensions of FGS. Optimal parameters of ultrasonic dispersion of slag suspensions are established: the frequency of ultrasonic vibrations is equal to 44 kHz; the dispersion temperature is 25 ± 2 °C; the dispersion time is 15 min. It was found that the application of ultrasonic dispersion to slag suspensions with the observance of dispersion conditions can increase the aggregative and sedimentation stability of FGS suspension by 2-3 times in comparison with the mechanical mixing of suspensions. The strength of samples with suspensions of FGS prepared using UST under the recommended dispersing conditions increased by 19 to 39% in the first day; for 28 days of hardening - by 19 - 36%, which allows using slag suspensions in the production of cement composite materials and concretes based on them.

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Butler, Jason E. "Suspension dynamics: moving beyond steady." Journal of Fluid Mechanics 752 (July 4, 2014): 1–4. http://dx.doi.org/10.1017/jfm.2014.278.

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AbstractThe dynamics of flowing, concentrated suspensions of non-colloidal particles continues to surprise, despite decades of work and the widespread importance of suspension transport properties to industrial processes and natural phenomena. Blanc, Lemaire & Peters (J. Fluid Mech., 2014, vol. 746, R4) report a striking example. They probed the time-dependent dynamics of concentrated suspensions of rigid and neutrally buoyant spheres by simultaneously measuring the oscillatory rheology and the sedimentation rate of a falling ball. The sedimentation velocity of the ball through the suspension depends strongly on the frequency of oscillation, though the rheology was found to be independent of frequency. The results demonstrate the complexities of suspension flows and highlight opportunities for improving models by exploring suspension dynamics and rheology over a wide range of conditions, beyond steady and unidirectional ones.

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Liu, Yung Sheng, Tswn Syau Tsay, Tsai Chu Wang, and Chi Fan Liu. "The Impact of Bicycle Suspension on Pedaling Forces." Applied Mechanics and Materials 479-480 (December 2013): 338–42. http://dx.doi.org/10.4028/www.scientific.net/amm.479-480.338.

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Front and/or rear suspensions of bicycles become popular for the purpose of riding comfort especially for mountain bicycle. Suspension system include damper for shock absorbing and spring for rebounding. Therefore suspension systems would increase bicycle riding effort since damper dissipates energy. ADAMS®/LifeMOD® are proposed in this research to establish a Bicycle-Human Integrated Multibody Dynamic Model to investigate the impact of bicycle suspensions on cyclists leg muscle forces under various pedaling conditions. Muscles compared include adductor magnus, rectus femoris, vastus lateralis and semitendinosus. Pedaling conditions include riding on flat road, over a road bump, and climbing slope. The results indicate that suspension system increases the pedaling forces of vastus lateralis and semitendinosus. However suspension system decreases the pedaling forces of adductor magnus and rectus femoris. The integrated model built in this research may be used as reference for designing bicycle suspension systems. In addition, the results of this study can be used as the basis of leg weight training for long-distance off-road cyclists to strengthen certain muscles.

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Tikhov-Tinnikov, Dmitry A. "METHODS FOR MONITORING THE TECHNICAL CONDITION OF THE SUSPENSION OF VEHICLE UNDER OPERATING CONDITIONS." International Journal of Advanced Studies 11, no. 4 (December 30, 2021): 18–30. http://dx.doi.org/10.12731/2227-930x-2021-11-4-18-30.

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Suspension faults can reduce wheel traction and therefore reduce vehicle stability. Existing diagnostic methods for the suspension do not take into account the stability of the vehicle. To control stability, it is proposed to use road and bench methods, characterized by suspension vibrations and constant lateral force. Theoretical studies were carried out using mathematical models based on the description of the functioning of sprung and unsprung vehicle masses, as well as elastic tires. Experimental studies include bench tests of tires, shock absorbers and silent blocks of various technical conditions, as well as road studies of the kinematic parameters of the M1 category vehicle. As a result, a road method for monitoring the technical condition of shock absorbers was developed, taking into account their influence on stability indicators. Purpose – Theoretical substantiation and experimental confirmation of the method for diagnosing suspension systems by parameters related to the stability of the vehicle movement. Methodology includes experimental methods, mathematical modeling methods and numerical methods for solving differential equations. Results: experimental methods and mathematical apparatus were developed to study the influence of the parameters of the suspension system on the stability of the movement of vehicles. Practical implications: the results can be used by organizations and institutions involved in the development of diagnostic methods for vehicles.

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Matheus, Boeira Braga, and Cristina dos Santos Rocha Sandra. "Effect of Surface Properties on Particle Growth Kinetics for Polymer Coating in Spouted Bed." Materials Science Forum 727-728 (August 2012): 1616–21. http://dx.doi.org/10.4028/www.scientific.net/msf.727-728.1616.

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In this research, glass beads with size range between 1.68 and 2mm were coated with 5 polymeric suspensions. The suspensions formulations differ in relation to their employment and physical properties (solids concentration, surface tension and rheology), generating different characteristics of wettability and adhesion with the nucleus. The aim of this study was to evaluate particle coating in a spouted bed through analysis of particle growth in terms of solid surface energy, wettability, and adhesion before and after the formation of the first layer of polymeric film on the particle. The solid-suspension and film-suspension systems were characterized by contact angle and surface energy. The operating conditions were fixed for all suspensions: 1.5 kg of beads, air velocity of 0.369 m/s, air temperature of 60 °C, suspension flow rate of 4 ml and atomizing pressure of 10 psig. Analyzing particle growth kinetics, different behaviors were observed and related not only to glass-suspension wettability, but also to polymeric film-suspension surface properties.

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Berlin, J., C. Rügenhagen, M. Rippert, and S. Erdogan. "Effects of Culture Conditions on Isoflavonoid Levels of Transformed and Non-Transformed Cultures of Lupinus -a Comparison of Suspension and Hairy Root Cultures." Zeitschrift für Naturforschung C 46, no. 9-10 (October 1, 1991): 735–42. http://dx.doi.org/10.1515/znc-1991-9-1004.

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Abstract Some highly productive suspension and hairy root cultures were found among several transformed cultures of Lupinus polyphyllus and L. hartwegii. A transformed suspension culture Lupo 30150 and a root culture Luha 15834 containing the highest specific isoflavone glucoside content were characterized and compared with normal phytohormone-dependent lines with respect to product stability as well as to their responsiveness to external triggers, e.g. response to changes in the medium. While phytohormone-dependent suspension cultures lost their initial ability to form increased levels of isoflavonoids on phytohormone-free medium, the transformed phytohorm one-independent suspension Lupo 30150 remained a highly productive line, despite the fact that its specific levels decreased to 60% of the initial values during several years in liquid medium. Highest stability of product patterns and levels were noted for the transformed root culture. Phytohorm ones had little effect on growth and isoflavonoid levels in suspension cultures, while they reduced both strongly in root cultures. In the presence of 2,4-D the root culture changed into an aggregated low producing suspension culture from which the root state was recovered on phytohorm one-free medium. As long as the root state was main tained, isoflavonoid levels could not be distinctly improved by media variation while specific isoflavonoid levels of suspensions were increased by stress factors such as phosphate depletion. When suspensions were transferred to fresh medium phenylalanine ammonia-lyase was greatly induced within 24 h, while the activity remained nearly unchanged in root cultures.

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Ayazi Shamlou, P., P. Synowiec, and A. Zolfagharian. "Critical suspension conditions in stirred crystallizers." Chemical Engineering Journal and the Biochemical Engineering Journal 55, no. 1-2 (August 1994): 45–51. http://dx.doi.org/10.1016/0923-0467(94)87005-5.

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Choi, Kyujeong, Jooseon Oh, Heung-Sub Kim, Hyun-Woo Han, Jung-Ho Park, Geun-Ho Lee, Jaho Seo, and Young-Jun Park. "Experimental Study on the Dynamic Characteristics of Hydro-Pneumatic Semi-Active Suspensions for Agricultural Tractor Cabins." Applied Sciences 10, no. 24 (December 16, 2020): 8992. http://dx.doi.org/10.3390/app10248992.

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This study aims to establish a test method to obtain the dynamic characteristics of hydraulic-pneumatic semi-active suspensions used in tractor cabins. Because dynamic characteristics are utilized in simulation models for developing suspension control logic and must be secured to improve control performance, an accurate test method must be established. The dynamic characteristics of the suspension, i.e., the spring constant and damping coefficient, were obtained by changing the current and velocity conditions. An exciter was used as a test device to control the displacement and velocity of the hydraulic cylinder. In order to derive the spring constant of the suspension, a low-speed reciprocating motion test was performed to obtain the force-displacement diagram and to derive the damping coefficient; 48 tests were performed under 6 velocity conditions and 8 current conditions to obtain a force-velocity diagram for each result. The spring constant of the suspension was confirmed using the slope of the trend line in the force-displacement diagram obtained through the low-speed reciprocating motion test of the suspension. In addition, the damping coefficient was calculated using the force-velocity diagram obtained through the reciprocating motion test of the suspension under various current and velocity conditions.

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Huang, Chung Neng, Kuo Han Chen, and David T. W. Lin. "Development of an Novel Adaptive Suspension System Based on Ball-Screw Mechanism." Applied Mechanics and Materials 477-478 (December 2013): 128–31. http://dx.doi.org/10.4028/www.scientific.net/amm.477-478.128.

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For the passive and semi-active suspensions are characterized as with constant parameters which cannot cope with time-variant road conditions, the suspension results are difficult to be satisfied. Although, the active ones are better than previous two on suspension performance, until now which are still far from real application for the drawbacks of complicated structure, large volume, costly, and difficult maintenance. Here, Ball Screw (BS) is with the characteristics of smaller volume, precise positioning, and well handling high-speed forward and backward transmissions. Instead of hydraulic or pneumatic mechanisms used for vehicle suspension, BS is adopted to be the main body of the proposed New Adaptive Suspension System (NASS). Besides, in order to overcome the unavoidable time-delay resulted from mechanical or computational operations, the Kalman filter, integrated with suspension controller, is used to estimate the road conditions. The effectiveness and feasibility of this proposal are confirmed through simulation studies.

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Li, Xiaopeng, Fanjie Li, and Dongyang Shang. "Dynamic Characteristics Analysis of ISD Suspension System under Different Working Conditions." Mathematics 9, no. 12 (June 10, 2021): 1345. http://dx.doi.org/10.3390/math9121345.

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The “inerter-spring-damper” (ISD) suspension system is a suspension system composed of an inerter, spring, and damper. To study the ride comfort and stability of the vehicle by using the ISD suspension system, a vehicle model with ISD suspension is established in this paper. The vehicle model including vertical, pitch, roll, and yaw motion of the vehicle body. Based on the vehicle model, the differential equation of motion with ISD suspension is obtained. The dynamic responses of the ISD suspension system are investigated by using different road excitations. At the same time, the influence of coupled excitation and single excitation on the vibration reduction performance of the ISD suspension system is studied. Then, the dynamic responses of ISD suspension and passive suspension are compared, and the improvement of comprehensive vibration reduction performance of ISD suspension system is quantitatively analyzed. The numerical results illustrate the ISD suspension has the optimal vehicle speed under different road excitations, and the comprehensive vibration reduction performance of the ISD suspension is the best when driving at the optimal vehicle speed. Under different types of road excitation, ISD suspension shows excellent comprehensive vibration reduction performance. ISD suspension is more suitable for vibration reduction of complex roads than that of a single road.

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Chen, Yikai, Sen Huang, Lloyd Davis, Haiping Du, Qin Shi, Jie He, Qiang Wang, and Wenting Hu. "Optimization of Geometric Parameters of Longitudinal-Connected Air Suspension Based on a Double-Loop Multi-Objective Particle Swarm Optimization Algorithm." Applied Sciences 8, no. 9 (August 24, 2018): 1454. http://dx.doi.org/10.3390/app8091454.

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Longitudinal-connected air suspension has been proven to have desirable dynamic load-sharing performances for multi-axle heavy vehicles. However, optimization approaches towards the improvement of comprehensive vehicle performance through the geometric design of longitudinal-connected air suspension have been considerably lacking. To address this, based on a 5-degrees-of-freedom nonlinear model of a three-axle semi-trailer with longitudinal air suspension, taking the changes of driving conditions (road roughness, speed, and load) into account, a height control strategy of the longitudinal-connected air suspension was proposed. Then, in view of the height of the air spring under various driving conditions, the support vector regression method was employed to fit the relationship models between the performance indices and the driving conditions, as well as the suspension geometric parameters (inside diameters of the air line and the connectors). Finally, to tackle the uncertainties of driving conditions in the optimization of suspension geometric parameters, a double-loop multi-objective particle swarm optimization algorithm (DL-MOPSO) was put forward based on the interval uncertainty theory. The simulation results indicate that compared with the longitudinal-connected air suspension using two traditional geometric parameters, the optimization ratios for dynamic load sharing coefficient and root-mean-square acceleration at various spring heights are between −1.04% and 20.75%, and 1.44% and 35.1%, respectively. Therefore, based on the signals measured from the suspension height sensors, through integrated control of inflation/deflation valves of air suspensions, as well as the valves’ inside connectors and air lines, the proposed DL-MOPSO algorithm can improve the comprehensive driving performance of the longitudinal-connected three-axle semi-trailer effectively, and in response to changes in driving conditions.

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Bundithya, W., and S. L. Kitto. "OPTIMAL CONDITIONS FOR CELL SUSPENSION CULTURES OF THLASPI CAERULESCENS AND BRASSICA NAPUS." HortScience 30, no. 2 (April 1995): 186b—186. http://dx.doi.org/10.21273/hortsci.30.2.186b.

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Thlaspi caerulescens (Brassicaceae), known as a Zn hyper accumulator, is able to accumulate and tolerate Zn, Ni, Cu, and Cd at high concentrations in its biomass. We are examining the feasibility of using cell suspensions of T. caerulescens and B. napus to study the effect of selected heavy metals on growth and nutrient uptake. Callus was initiated by culturing seedlings on basal medium containing MS salts supplemented with MS or B5 vitamins, 1, 2, 5, or 10 mg 2,4-D/liter, and 0.7% Phytagar. Cell suspensions were initiated by transferring calli to liquid basal medium containing MS or B5 vitamins, and 1 or 2 mg 2,4-D/liter, and were incubated on a gyratory shaker at 120 rpm. Growth of suspensions inoculated at 0.2, 0.4, or 0.6 g/25 ml was monitored for 13 days. Optimal conditions required to initiate and maintain suspension cultures of T. caerulescens and B. napus include MS medium supplemented with B5 vitamins and 1 mg 2,4-D/liter, an inoculation density of 0.4 g/25 ml, and a 2-week subculture schedule.

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Kulikova, Mayya V., Oksana S. Dement’eva, Maria V. Chudakova, and Mikhail I. Ivantsov. "INFLUENCE OF PREPARING NANOSCALE SUSPENSIONS METHOD ON ITS PHYSICO-CHEMICAL AND CATALYTIC PROPERTIES UNDER THE CONDITIONS OF FISCHER-TROPSCH SYNTHESIS." IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENIY KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA 61, no. 9-10 (October 22, 2018): 70–76. http://dx.doi.org/10.6060/ivkkt20186109-10.5863a.

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Methods for the formation of stable iron-containing suspensions that exhibit activity in the conversion of synthesis gas to C5+ hydrocarbons by the Fischer-Tropsch method are proposed. By XRD and DLS methods it was determined that the formation of the Fe2O3 phase with a bimodal particle size distribution of 50 and 295 nm results in the formation of a suspension by the drop thermolysis method − the gradual introduction of the active metal precursor solution into the dispersion medium (mixture of hydrocarbons C19H40-C32H66). Pulsed introduction of the active metal precursor solution (flash-pyrolysis) into the reactor zone leads to the formation of the Fe3O4 phase with a particle size of 91 and 460 nm. By TEM and AFM methods it was established that, regardless of the slurry forming method, large active phase particles are agglomerates of a finer fraction of particles with an average size of 42 nm. The obtained suspensions demonstrated high activity in the Fischer-Tropsch synthesis under the slurry-reactor conditions, however, the degree of CO conversion is slightly higher in the case of the catalytic suspension prepared by the drop thermolysis method. It is shown that the method of forming the suspension significantly affects the fractional composition of the resulting reaction products. In the presence of a suspension obtained by drop thermolysis, the yield of liquid hydrocarbons reaches 130 g/m3, while a high content of C19+ hydrocarbons is observed. The system formed by the method of flash-pyrolysis makes it possible to obtain mainly the gasoline (C5-C10) and diesel (C11-C18) hydrocarbon fractions. It should be noted that the products of the reaction have a high content of unsaturated hydrocarbons, which reaches 55%. Thus, the composition of the final products of FTS can be controlled by the choice of the catalytic suspension prepared method. For citation: Kulikova M.V., Dement’eva O.S., Chudakova M.V., Ivantsov M.I. Influence of preparing nanoscale suspensions method on its physico-chemical and catalytic properties under the conditions of Fischer-Tropsch synthesis. Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2018. V. 61. N 9-10. P. 70-75

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Robinson, J. H., Serena Best, Z. Ahmad, and Mohan J. Edirisinghe. "The Effect of Reaction Conditions on Hydroxyapatite Particle Morphology and Applications to the Reticulated Foam Method of Scaffold Production." Key Engineering Materials 361-363 (November 2007): 3–6. http://dx.doi.org/10.4028/www.scientific.net/kem.361-363.3.

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The production of nano-scale hydroxyapatite (HA) suspensions to be used for the reticulated foam method of scaffold production was investigated at temperatures of between 10 and 60OC. An increase in reaction temperature was associated with an increase in the particle size and some decrease in the aspect ratio of the particles. Pre-treatment of the polyurethane foam template using PPDS (potassium peroxodisulfate) solution resulted in a significantly improved coating of HA when compared to the untreated samples or those treated with ethanol. Initial trials coating the polyurethane with HA produced at the different reaction temperatures showed a superior coating with the suspension produced at 10OC compared to that at 60OC. A scaffold was produced using the HA suspension produced at room temperature, but further understanding of the suspension properties and the optimum conditions for coating of the PU foam are required for improved mechanical performance.

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Nabagło, Tomasz, Andrzej Jurkiewicz, and Janusz Kowal. "Semi-Active Suspension System for 2S1 Tracked Platform in Application of Improvement of the Vehicle Body Stability." Applied Mechanics and Materials 759 (May 2015): 77–90. http://dx.doi.org/10.4028/www.scientific.net/amm.759.77.

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In the article, a new solution of a semi-active suspension system is presented. It is based on a sky-hook strategy model. This solution in 2S1 tracked platform is applied to improve body vehicle stability and driving comfort. The solution is applied in two versions of the 2S1 vehicle suspension model. First one is a basic model. This suspension is based on existing construction of the 2S1 platform suspension. It is based on torsion bars. Second one is a modified model, based on spiral torsion springs. In this model a new solution of idler mechanism is applied. It provides constant tension of the tracks. Semi-active suspensions simulations results are compared with results of models with passive versions of the suspension to highlight the improvement level. Simulations are conducted in the Yuma Proving Ground conditions. Results of all models simulations are compared and analyzed to improve stability and comfort level in conditions of the modern battlefield. Stability level is analyzed for weapon aiming tasks. Comfort level is analyzed for the vehicle crew efficiency.

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Silva, Alaine Cardoso, Priciane Martins Parreira, Humberto Molinar Henrique, Carlos Eduardo Batista Avelar, João Jorge Ribeiro Damasceno, and Carla Eponina Hori. "Study and Optimization of Reaction of Hydration of Calcium Oxide to Produce Slaked Lime Suspension." Materials Science Forum 591-593 (August 2008): 816–20. http://dx.doi.org/10.4028/www.scientific.net/msf.591-593.816.

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Slaked lime is a suspension of hydrated lime in water that can contain up to 40% of solids in suspension. The quality of the suspensions of slaked lime depends on the quality of lime used and on a careful choice of the conditions during the hydration process. A high quality slaked lime is a product with a small quantity of insoluble residues, high specific surface area, high alkaline content and small particle size. Therefore, the objective of this work was to study the best conditions of temperature and concentration to produce a superior slaked lime. A statistic analysis was performed using the experimental results in order to optimize the operational conditions of the hydration process. The use of hydration water around 74 °C, of small particles of CaO (0.144 mm) and of a CaO/H2O ratio around 220 g/L contributed to the production a slaked lime suspension of fine quality.

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Moritz, Kirsten, and Eberhard Müller. "Electrophoretic Deposition of Ceramic Powders-Influence of Suspension and Processing Parameters." Key Engineering Materials 314 (July 2006): 51–56. http://dx.doi.org/10.4028/www.scientific.net/kem.314.51.

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The electrophoretic deposition (EPD) of AlN, Al2O3 and SiC, respectively, from ethanolic suspensions stabilised by suitable organic additives has been investigated. A main topic of this paper is the EPD in the direction of the gravitational force. Using an AlN suspension, the deposit weight depending on the experimental parameters was determined. The deposition was carried out under constant voltage or constant current conditions. Several factors influencing the effective electric field strength will be discussed. It could be shown that the conductivity of the suspension results mainly from the free ionic species. By EPD from the different suspensions, green bodies with monomodal pore size distributions were produced. The electrophoretic deposition of alumina from an ethanolic and from an aqueous suspension of the same composition led to similar results regarding the homogeneity of the particle packing in the deposits. The SiC suspension was also used for infiltrating woven carbon fibre mats by EPD in order to fabricate ceramic matrix composites.

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Jiang, Lin Ling, Wei Mo, Xiao Jing Yang, Tian Li Xue, and Shao Jian Ma. "Effect on Sedimentation Characteristics of Bentonite Suspension at Different Conditions." Applied Mechanics and Materials 333-335 (July 2013): 2004–9. http://dx.doi.org/10.4028/www.scientific.net/amm.333-335.2004.

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To better understand the sedimentation processes of bentonite, the sedimentation characteristic of bentonite suspension was studied by using the sedimentation analysis module of Dynamic Contact Angle Meter and Tensiometer. The results indicated that sedimentation characteristics of bentonite suspension were affected by the concentration and pH values of the suspension together with the dosage of dispersants. The natural sedimentation rates of bentonite suspension declined firstly with prolonging the sedimentation time and soon stabilized after about 50s. The sedimentation weight of particles hardly changed when the concentration ranged from 0.5% to 5.0%, while it increased significantly when ranged from 5.0% to 10.0%. The sedimentation weight and rate were relatively bigger at 4.4, 11.8 than that of 6.0, 7.9, and the maximum values appeared at pH11.8. Adding sodium pyrophosphate could improve the dispersibility of bentonite suspension.

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Faheem, Sajid, Vijay Baheti, Maros Tunak, Jakub Wiener, and Jiri Militky. "Comparative performance of flame retardancy, physiological comfort, and durability of cotton textiles treated with alkaline and acidic casein suspension." Journal of Industrial Textiles 48, no. 6 (December 28, 2017): 969–91. http://dx.doi.org/10.1177/1528083717750885.

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The objective of the present study was to investigate the effect of coating of different concentrations and pH of aqueous casein suspension on thermo-oxidative properties, flame retardant behavior as well as physiological comfort of cotton fabrics. The flame retardant behavior was found to increase with increase in concentration of casein suspension in both alkaline and acidic pH conditions. The burning rate of 2.1 mm/s and 2.4 mm/s was measured for the samples of 150 g/L casein suspensions in acidic and alkaline pH, respectively. Moreover, better thermo-oxidative properties were obtained for the samples of casein suspension prepared in acidic pH than alkaline pH. The 150 g/L casein produced 19% and 28% residue, respectively for alkaline and acidic suspensions at 600℃. Furthermore, the phenomenon of intumescence was largely observed in case of samples coated with acidic casein suspension due to easier release of ammonia from protonated casein. These samples further exhibited relatively better durability against water washing and UV ageing as compared to those treated with alkaline casein suspension, however delivered poor physiological comfort properties due to blockage of fabric porosity by higher viscosity of casein in acidic pH.

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Setz, Luiz Fernando Grespan, and Sonia Regina Homem de Mello-Castanho. "Determining the Lanthanum Chromite Zeta Potential in Aqueous Media." Materials Science Forum 660-661 (October 2010): 1145–50. http://dx.doi.org/10.4028/www.scientific.net/msf.660-661.1145.

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Lanthanum Chromite may used as interconnect for SOFC’s applications due its particular intrinsic properties as stability in both oxidant and reducing environments and electrical conductivity. However to manufacture these devices that generally present complex shapes as grooved plates and fine pipes, they are necessary the use of the conformation techniques such as screen printing, slip casting, tape casting, extrusion moulding, etc. that are related with colloid processing. Independent of the processing techniques chosen the control of the suspension conditions is important to obtain reproducibility and homogeneous products as final result. In this sense, all contribution to understand the behaviour of the LaCrO3 fine particles in liquid suspension as the surface state using the Zeta’s Potential concepts may supplies information by the forecast of the behaviour during the shaped processing. The aqueous suspensions behaviour was studied utilizing doped lanthanum chromite powders, attained by combustion synthesis. The eletrophoretic mobility measurements of particles in suspension, prepared with the different conditioned powders were made. The electrolyte compositions as function of the pH varying from 2 to 12 were tested. The Zeta potentials and the stability conditions for stable suspensions prepared were determined. The viscosity curves are also appraised.

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Wafi A. Mabrouk and M. F. L. Abdullah. "SIMULATION OF MATHEMATICAL MODEL FOR MONORAIL SUSPENSION SYSTEM UNDER DIFFERENT TRACK CONDITIONS." Journal of The Institution of Engineers, Malaysia 79, no. 2 (December 13, 2018): 15–31. http://dx.doi.org/10.54552/v79i2.3.

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Designing a new monorail suspension system for an existing monorail bogie to accommodate larger cars, locomotives and more passengers is a difficult and complicated problem to solve. This paper introduces a simulation of a mathematical model for a monorail suspension system that can be used as an analytical tool to investigate and predict the behavior of the model under different speeds and track conditions. In this paper, the simulation is performed to predict some dynamic characteristics monorail suspension system. This research work concentrates on the simulation of 15 degrees of freedom full-car Monorail suspension system. The model features the Monorail body, Front bogie, and rear bogie geometries, adopted equations of motion of the monorail suspension system and system matrices. Numerical Central Difference method was used to obtain the system responses subject to sinusoidal Track excitations. Three Track scenarios that have different loads and different driving speeds were conducted to investigate the monorail suspension system. The system results are analysed in terms of their dynamic responses. Fourier Fast transforms was used to calculate the frequency ranges of dynamic responses. As a result, some very important characteristics of the Monorail suspension system were revealed, with indicators that help to understand the effects of driving speeds and different loads, which can be used to better understand the system dynamic performance, to improve Monorail suspension system designs flaws detection.

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DOLGOPYAT, DMITRY, and PÉTER NÁNDORI. "On mixing and the local central limit theorem for hyperbolic flows." Ergodic Theory and Dynamical Systems 40, no. 1 (May 11, 2018): 142–74. http://dx.doi.org/10.1017/etds.2018.29.

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We formulate abstract conditions under which a suspension flow satisfies the local central limit theorem. We check the validity of these conditions for several systems including reward renewal processes, Axiom A flows, as well as the systems admitting Young’s tower, such as Sinai’s billiard with finite horizon, suspensions over Pomeau–Manneville maps, and geometric Lorenz attractors.

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Castellani, Alberto. "Safety Margins of Suspension Bridges Under Seismic Conditions." Journal of Structural Engineering 113, no. 7 (July 1987): 1600–1616. http://dx.doi.org/10.1061/(asce)0733-9445(1987)113:7(1600).

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Moiseeva, K. M., and A. Yu Krainov. "Spark ignition critical conditions for aluminum-air suspension." Journal of Physics: Conference Series 1128 (November 2018): 012082. http://dx.doi.org/10.1088/1742-6596/1128/1/012082.

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Lehn, Mary C., Kevin J. Myers, and André Barker. "Agitator design for solids suspension under gassed conditions." Canadian Journal of Chemical Engineering 77, no. 5 (October 1999): 1065–71. http://dx.doi.org/10.1002/cjce.5450770537.

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31

Cardou, Alain, André Leblond, and Louis Cloutier. "Suspension Clamp and ACSR Electrical Conductor Contact Conditions." Journal of Energy Engineering 119, no. 1 (April 1993): 19–31. http://dx.doi.org/10.1061/(asce)0733-9402(1993)119:1(19).

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Divinsky, B. V., and R. D. Kosyan. "Bottom Sediment Suspension under Irregular Surface Wave Conditions." Oceanology 59, no. 4 (July 2019): 482–90. http://dx.doi.org/10.1134/s0001437019040039.

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Limer, Adam, Alex Heming, Ian Shirley, and David Haddleton. "Living radical polymerisation in heterogeneous conditions—suspension polymerisation." European Polymer Journal 41, no. 4 (April 2005): 805–16. http://dx.doi.org/10.1016/j.eurpolymj.2004.11.002.

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Wichterle, Kamil. "Conditions for suspension of solids in agitated vessels." Chemical Engineering Science 43, no. 3 (1988): 467–71. http://dx.doi.org/10.1016/0009-2509(88)87007-6.

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Frees, G. M., and D. K. Miu. "Experimental and Numerical Analysis of Read/Write Head Suspension Dynamics for High-Performance Floppy Drive Systems." Journal of Vibration and Acoustics 112, no. 1 (January 1, 1990): 26–32. http://dx.doi.org/10.1115/1.2930093.

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Read/write head suspensions are critical components of high-performance floppy disk drives. Their dynamics affect head/media compliance, wear, and tracking performance. Vibration measurements are necessary in order to verify and adjust finite element models, to observe the influence of actual loading and operating conditions, and to study the effects of unmodeled components such as electrical wires and adhesives. A nonintrusive measurement technique using a Laser Doppler Vibrometer is utilized to measure the submicron vibrations. Excitation of the suspension is provided by a specially designed miniature air hammer and a piezoelectric transducer. Natural frequencies and mode shapes are extracted from the measurements and compared with numerical data from the finite element model. Research shows that boundary conditions are the most important parameters in the modeling of the suspension. A new design is proposed, using the verified model, to increase the tracking performance of the suspension. Synergy between experimentation and numerical analysis is emphasized.

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Chen, De Wei, Xiao Ling Ge, Quen Tin Shi, and Jiu Wang Tian. "Research on the Ultra-Fine Titanium Dioxide Suspension Stability and Fractal." Advanced Materials Research 361-363 (October 2011): 288–95. http://dx.doi.org/10.4028/www.scientific.net/amr.361-363.288.

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Using scanning electron microscope, the microscopic pictures of the surface on sediment have been obtained from the sub-micron titanium dioxide suspensions without dispersant or adding different types of dispersants. Deposits of titanium dioxide suspension have been observed and the mechanism of the dispersant has been analyzed. Meanwhile, deposits of titanium dioxide gray distribution figure have been gained by self-compiled Matlab program, which proved that the surface sediments is fractal, and the fractal dimension has been calculated under different conditions. The rules between suspension stability and fractal dimension have been achieved.

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Erne, Martin, Daniel Kolar, Kai Möhwald, and Friedrich Wilhelm Bach. "Suspension Plasma Spraying of Triboactive Coatings for High Temperature Applications." Key Engineering Materials 438 (May 2010): 139–46. http://dx.doi.org/10.4028/www.scientific.net/kem.438.139.

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In recent years, suspension plasma spraying (SPS) was investigated regarding the spraying of functional coatings with deterministic abilities. In this contribution the possibilities are discussed to achieve oxide ceramic coatings based on titania by SPS, which show a reduction of their coefficient of friction under dry sliding conditions. Besides the possibility to mix different feedstock suspensions in the process, the achievable low thickness and homogenous microstructure of suspension-sprayed coatings shall allow an operation in fields, where high demands towards the adhesion, cohesion and near net shape are made.

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Akther, S., J. Hwang, and H. Lee. "Sedimentation characteristics of two commercial bentonites in aqueous suspensions." Clay Minerals 43, no. 3 (September 2008): 449–57. http://dx.doi.org/10.1180/claymin.2008.043.3.09.

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AbstractThe sedimentation characteristics of two commercial bentonites, Tixoton (organically treated) and Montigel-F (untreated), were investigated using a 3% w/v clay suspension at different concentrations (1, 3.5 and 10%) of NaCl and pH values (2, 7 and 12). Settling rates, floc diameters and sediment volumes were derived from changes in light transmittance using a Turbiscan Ma 2000 instrument.Both bentonite suspensions were unstable (flocculated) in NaCl solutions. The settling rate increased with increasing concentration of NaCl and was directly related to floc diameter. The sediment volume reduced with increasing NaCl concentrations, a result of greater double layer compression caused by increased ionic strength. At comparable salt concentrations, the organically-treated bentonite (Tixoton) settled at a much slower rate and had a greater sedimentation volume. The suspensions of both organically-treated and untreated bentonites were stable (dispersed) above pH 7 and unstable in acidic conditions. The settling rate for Tixoton under acid conditions was much smaller than that for the Montigel-F. Differences in sedimentation characteristics between the two bentonite samples are probably due to the presence of an anionic polymer (carboxymethyl cellulose: CMC) in Tixoton.The viscosity of the bentonite suspensions was also studied. The viscosity of the clay suspension is closely related to clay dispersivity in solution. The CMC was highly effective in increasing the viscosity of the bentonite suspensions, but only under neutral and alkaline conditions.

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Style, Robert W., and Stephen S. L. Peppin. "Crust formation in drying colloidal suspensions." Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 467, no. 2125 (June 30, 2010): 174–93. http://dx.doi.org/10.1098/rspa.2010.0039.

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During the drying of colloidal suspensions, the desiccation process causes the suspension near the air interface to consolidate into a connected porous matrix or crust. Fluid transport in the porous medium is governed by Darcy’s law and the equations of poroelasticity, while the equations of colloid physics govern processes in the suspension. We derive new equations describing this process, including unique boundary conditions coupling the two regions, yielding a moving-boundary model of the concentration and stress profiles during drying. A solution is found for the steady-state growth of a one-dimensional crust during constant evaporation rate from the surface. The solution is used to demonstrate the importance of the system boundary conditions on stress profiles and diffusivity in a drying crust.

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Iwaniec, Joanna, and Marek Iwaniec. "Output-Only Identification of Vibratory Machine Suspension Parameters under Exploitational Conditions." Solid State Phenomena 248 (March 2016): 175–85. http://dx.doi.org/10.4028/www.scientific.net/ssp.248.175.

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The paper concerns model based identification of vibratory machine body suspension system on the basis of dynamic responses measured under exploitational conditions. The research was carried out by means of the restoring force, boundary perturbation and direct parameter estimation techniques which, on the contrary to classical nonlinear system identification methods, requires neither excitation measurements nor linear behaviour of the considered system around an operating point. At the first stage of the research, parameters of the machine body suspension system were identified. Results accuracy was verified by determining percentage relative error of mass estimation with respect to the value calculated based on the machine geometrical and material properties. In the next step, the suspension system was modified by introduction of a nonlinear damping system. Obtained results proved that the assumed identification method is convenient for vibratory machine suspension condition monitoring and determining forces transferred on machine foundations.

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Song, Yong, Shichuang Liu, Jiangxuan Che, Jinyi Lian, Zhanlong Li, and Qinglu Shi. "A Pneumatic Artificial Muscle Bionic Kangaroo Leg Suspension." Recent Patents on Mechanical Engineering 12, no. 4 (December 26, 2019): 357–66. http://dx.doi.org/10.2174/2212797612666190808100422.

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Background: Vehicles generally travel on different road conditions, and withstand strong shock and vibration. In order to reduce or isolate the strong shock and vibration, it is necessary to propose and develop a high-performance vehicle suspension system. Objective: This study aims to report a pneumatic artificial muscle bionic kangaroo leg suspension to improve the comfort performance of vehicle suspension system. Methods: In summarizing the existing vehicle suspension systems and analyzing their advantages and disadvantages, this paper introduces a new patent of vehicle suspension system based on the excellent damping and buffering performance of kangaroo leg, A Pneumatic Artificial Muscle Bionic Kangaroo Leg Suspension. According to the biomimetic principle, the pneumatic artificial muscles bionic kangaroo leg suspension with equal bone ratio is constructed on the basis of the kangaroo leg crural index, and two working modes (passive and active modes) are designed for the suspension. Moreover, the working principle of the suspension system is introduced, and the rod system equations for the suspension structure are built up. The characteristic simulation model of this bionic suspension is established in Adams, and the vertical performance is analysed. Results: It is found that the largest deformation happens in the bionic heel spring and the largest angle change occurs in the bionic ankle joint under impulse road excitation, which is similar to the dynamic characteristics of kangaroo leg. Furthermore, the dynamic displacement and the acceleration of the vehicle body are both sharply reduced. Conclusion: The simulation results show that the comfort performance of this bionic suspension is excellent under the impulse road excitation, which indicates the bionic suspension structure is feasible and reasonable to be applied to vehicle suspensions.

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Mishra, Prakash, and Farhad Ein-Mozaffari. "Critical review of different aspects of liquid-solid mixing operations." Reviews in Chemical Engineering 36, no. 5 (July 28, 2020): 555–92. http://dx.doi.org/10.1515/revce-2018-0017.

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AbstractMechanically stirred slurry tanks are utilized in several industries to perform various unit operations such as crystallization, adsorption, ion-exchange, suspensions polymerization, dispersion of solid particles, leaching and dissolution, and activated sludge processes. The major goal of this review paper is to critically and thoroughly analyse the different aspects of previous research works reported in the literature in the field of liquid-solid mixing. This paper sheds light on the advantages and limitations of various particle concentration measurement methods employed to assess the suspension quality and the extent of solid suspensions in slurry reactors. Attempts are being made to identify and compare various mathematical models and methods to quantify particle dispersion and distribution in slurry reactors. It has been shown that various factors such as geometric configurations, agitation conditions, and physical characteristics of liquid and solid have pronounced influence on local suspension quality and power consumption. Computational fluid dynamics (CFD) modeling can be extremely useful in assessing the suspension of solid particles in slurry tanks. A critical review of different scale-up procedures employed for solid suspension and distribution in liquid-solid systems is presented as well. The findings of this review paper can be useful for future research works in liquid-solid mixing.

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Yagiz, N., and L. E. Sakman. "Robust Sliding Mode Control of a Full Vehicle Without Suspension Gap Loss." Journal of Vibration and Control 11, no. 11 (November 2005): 1357–74. http://dx.doi.org/10.1177/1077546305058268.

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A seven-degrees-of-freedom full vehicle model is used to design a robust controller and to investigate the performance of active suspensions without losing the suspension working space. Zero reference for vehicle body displacement finishes suspension working distance. Thus, a new approach is suggested in this paper. Force actuators are placed parallel to the suspensions and non-chattering sliding mode control is applied. Since any change in vehicle parameters because of different load or road conditions adversely affects the performance of the ordinary control methods, a robust control method is preferred. To obtain the desired improvement in ride comfort, we aim to decrease the magnitudes of the body vibrations and their accelerations. We present body bounce, pitch and roll motions of the vehicle with the conventional approach and the proposed approach without suspension gap loss, both in the time domain in the case of traveling over a step road profile and in the frequency domain. The results of both approaches are compared. The solution to the suspension gap loss problem has also been presented on periodic road surfaces. At the end of the paper, we discuss the improvement in the performance of the new controller with its robust behavior and the advantage of the new approach.

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Zhou, Yaoqun, Frank Gauterin, Hans-Joachim Unrau, and Michael Frey. "Experimental Study of Tire-Wheel-Suspension Dynamics in Rolling over Cleat and Abrupt Braking Conditions." Tire Science and Technology 43, no. 1 (April 1, 2015): 42–71. http://dx.doi.org/10.2346/tire.15.430102.

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ABSTRACT The braking performance of recent vehicles is controlled by the interaction between the antilock braking system (ABS) and the transmitted force between road and tire. Because of tire and suspension elasticity, an abrupt braking or the ABS regulation initiates tire belt and wheel axle oscillations, which lead to a closed loop of acceleration and force transmission in the tire-wheel-suspension assembly in both translational and rotational directions. As a result, the oscillation of wheel slip and wheel load can influence the force transmission potential in the contact patch and thus the braking distance as well. The objective of the presented study is to investigate the influence of the tire-wheel-suspension dynamics on the force transmission potential between tire and road. To obtain acceleration and force dynamics in the tire-wheel-suspension assembly without inducing the influence from other vehicle components, a McPherson suspension was isolated from a real car and adapted to the inner drum test bench at the Karlsruhe Institute of Technology, Institute of Vehicle System Technology. After mounting different tires, measurements were carried out under various driving conditions. First, tire measurements with a measuring hub were done on the test bench to obtain both quasistatic characteristics and dynamic response in rolling over cleat. Second, different tire-wheel-suspension assemblies were driven on the test bench while the wheel brake was initiated by a hydraulic braking system based on a modified ESP control unit. This modified unit allows generation of abrupt braking pressure slopes by a direct control of the valves. The accelerations of different wheel-suspension components and forces in the links were measured. In this article, the experimental study of the dynamics of a run-flat and a standard tire and their respective coupled assembly with the suspension excited by rolling over cleat and abrupt braking is presented. After a description of the experimental setup, the results of tire-wheel-suspension dynamics of two different tires will be analyzed, interpreted, and compared. Furthermore, a simulation model of the tire-wheel-suspension assembly with the FTire model and dynamic models of suspension components will be built up.

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Stańco, Mariusz, and Marcin Kowalczyk. "Analysis of Experimental Results Regarding the Selection of Spring Elements in the Front Suspension of a Four-Axle Truck." Materials 15, no. 4 (February 18, 2022): 1539. http://dx.doi.org/10.3390/ma15041539.

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Most special vehicles on public roads and off-road are equipped with various suspension systems. The suspensions used in trucks are designed to absorb the energy that results from overcoming uneven ground. These suspensions are divided into dependent and independent ones. Knowledge of the loads that occur while driving a vehicle, mainly off-road, is critical from the point of view of the adhesion and fatigue life of the suspension system. In the case of four-axle cars with 2 + 2 axles, in which the first two axles are equipped with a dependent suspension based on leaf springs, only one axle may carry the load. This paper attempts to analyze the results of experimental tests carried out on a vehicle in the conditions of roads with an unstable surface such as dirt roads, gravel roads, and roadless tracks. An analysis of fatigue life estimation is presented using equivalent stress values. It was also determined how the use of front axles load equalizing elements in the tested car influences their fatigue life.

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Bergman, Lotta, Jessica Rosenholm, Anna-Brita Öst, Alain Duchanoy, Pasi Kankaanpää, Jyrki Heino, and Mika Lindén. "On the Complexity of Electrostatic Suspension Stabilization of Functionalized Silica Nanoparticles for Biotargeting and Imaging Applications." Journal of Nanomaterials 2008 (2008): 1–9. http://dx.doi.org/10.1155/2008/712514.

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Different means of attaching streptavidin to surface functionalized silica particles with a diameter of 240 nm were investigated with special focus on suspension stability for electrostatically stabilized suspensions. The influence of two different fluorescent dyes covalently linked to the streptavidin on suspension stability was also studied. The results clearly show that the stability of the suspensions is crucially dependent on all functional groups present on the surface. The surface functions may either directly affect the effective surface charge if the functions contain charged groups, or indirectly by affecting the relative concentration of charged groups on the particle surface. Poly(ethylene imine)-functionalized silica particles, where the polymer is grown by surface hyperbranching polymerization, are shown to be promising candidates for bioapplications, as the zeta-potential can remain strongly positive even under biologically relevant conditions.

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Morrison, Jordan T., Ralph A. Lugo, Jim C. Thigpen, and Stacy D. Brown. "Stability of Extemporaneously Prepared Lansoprazole Suspension at Two Temperatures." Journal of Pediatric Pharmacology and Therapeutics 18, no. 2 (January 1, 2013): 122–27. http://dx.doi.org/10.5863/1551-6776-18.2.122.

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OBJECTIVE The purpose of this study was to examine the stability of a generic lansoprazole product in a 3 mg/mL sodium bicarbonate suspension under room temperature and refrigerated conditions. METHODS Lansoprazole suspensions (3 mg/mL) were prepared in triplicate using an 8.4% sodium bicarbonate vehicle for each storage condition (room temperature and refrigerated). During 1 month, samples from each replicate were periodically removed and analyzed for lansoprazole concentration by liquid chromatography–tandem mass spectrometry (LC-MS/MS). Each sample was spiked with 10 mg/L omeprazole to serve as the internal standard. A positive electrospray LC-MS/MS method was validated over the calibration range of 5 to 25 mg/L using Food and Drug Administration Guidance. The identities of the analyte and internal standard in the samples were verified by monitoring the MS/MS transitions of m/z 370 to m/z 252 and m/z 346 to m/z 198 for lansoprazole and omeprazole, respectively. Additionally, the pH of the suspensions was monitored throughout the study. RESULTS The stability of lansoprazole in the oral sodium bicarbonate suspension under refrigeration is compromised prior to what has been previously reported in the literature. Samples kept at room temperature lost >10% of the lansoprazole after 48 hours compared with the refrigerated samples, which maintained integrity up to 7 days. No statistically significant difference was found between the pH of the room temperature and refrigerated suspension samples, indicating that this factor is not the cause for the differences in stability at these two conditions. CONCLUSIONS This study suggests that the extemporaneously compounded lansoprazole oral suspension prepared in 8.4% sodium bicarbonate should not be stored in plastic oral syringes longer than 48 hours at room temperature and no longer than 7 days when refrigerated. These data indicate an expiration time earlier than that previously reported for the refrigerated product (14 days).

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Goodall, R. "Dynamic Characteristics in the Design of Maglev Suspensions." Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit 208, no. 1 (January 1994): 33–41. http://dx.doi.org/10.1243/pime_proc_1994_208_231_02.

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The paper reviews the essential functions which apply to any kind of suspension, and distinguishes between the various inputs to which a suspension is subjected. These are used to assess the particular characteristics of an electromagnetically suspended (Maglev) vehicle, and to identify considerations which have important implications for the controller design, irrespective of the design method. Some general equations are developed which interrelate the vehicle speed, the quality of the track and the passenger comfort requirements, and these are used to identify operational conditions for which a second stage of suspension becomes necessary (that is, in addition to that provided by the magnets). The importance of understanding the suspension's response to deterministic track inputs is also highlighted. Although the paper is directed towards Maglev, the analysis is strongly based upon a consideration of the suspension transfer functions, and so many of the principles are applicable to actively controlled supensions in general.

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V, Khaowroongrueng. "Bioequivalence of Oseltamivir Phosphate 6 mg/mL Powder for Oral Suspension Formulations in Healthy Thai Volunteers under Fasting Conditions." Bioequivalence & Bioavailability International Journal 5, no. 1 (2021): 1–7. http://dx.doi.org/10.23880/beba-16000146.

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Oseltamivir is an oral antiviral of choice indicated for treatment and prophylaxis of influenza A and B infections. Oseltamivir is an inactive prodrug of oseltamivir carboxylate, an active form exerting antiviral activity. Oseltamivir oral suspension is an alternative formulation for pediatric patients or adults with dysphagia. GPO-A-FLU ® , oseltamivir 6 mg/mL powder for oral suspension had been developed as a generic substitute for reference product, Tamiflu ® oral suspension. In this study, we investigated the pharmacokinetics and bioequivalence of the test oral suspension oseltamivir formulation with respect to the corresponding reference oral suspension formulation. A comparative open-label, randomized, single dose, two-way crossover study was conducted under fasting conditions. Blood samples were collected for 24 hours post-dose and the plasma was separated for oseltamivir assay using a validated liquid chromatography-mass spectrometry method. The pharmacokinetic parameters were determined from plasma concentration-time profiles after administration of the test and reference formulations. The pharmacokinetic parameters were in agreement with the previously published data. The primary pharmacokinetic parameters: AUC 0−tlast , AUC 0−  and C max obtained from 47 subjects who completed the study were statistically compared. The 90% confidence intervals of geometric least squares mean ratio (test/reference) for log-transformed parameters were within 80.00-125.00% of bioequivalence criteria: 92.33-98.52% for AUC 0−tlast , 92.28- 98.43% for AUC 0−  , and 81.82-94.26% for C max . Both products were generally well tolerated by healthy Thai subjects. This study successfully demonstrated bioequivalence between GPO-A-FLU ® and Tamiflu ® , and supported product registration.

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Yang, Wenzhi, Sultan Akhtar, Klaus Leifer, and Helena Grennberg. "Noncovalent Functionalization of Graphene in Suspension." ISRN Organic Chemistry 2013 (March 28, 2013): 1–7. http://dx.doi.org/10.1155/2013/656185.

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Suspensions of graphene, prepared from graphite foil by sonochemical exfoliation, have been treated with new nonpolar pyrenebutyric amides. The assemblies, in suspension and after deposition on solid supports, were characterized by NMR, absorption, and fluorescence spectroscopy and by transmission electron microscopy, where the well-defined shape and size of an appended [60]fulleropyrrolidine unit facilitates TEM detection of the nonstationary molecules. The accumulated evidence, also including direct comparisons of carbon nanotubes treated with pyrene amides under the same conditions, proves the successful noncovalent functionalization of graphene suspended in non-polar solvent with non-polar pyrene derivatives.

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Journal articles on the topic 'Suspension conditions'

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