Identical Operating Parameters Research Articles

Nickel, cyanide, zinc, and copper removal from the effluent using photo-electrocoagulation-oxidation

One emerging approach for eliminating organic and inorganic pollutants from wastewater is electrocoagulation, often coupled with traditional methods to enhance efficacy. This study investigates the simultaneous elimination of nickel (Ni), cyanide (CN), zinc (Zn), and copper (Cu) from the natural wastewater of a gold processing plant using the photo-electrocoagulation method with ozone as an oxidizing agent (ECOUV), both in continuous and batch modes, produced in situ. When performing the test in batch mode, CN, Ni, Cu, and Zn were removed at their peak of 100, 79.1, 100, and 89 %, respectively, at pH=10 and at i = 15 mA/cm2 using graphite-aluminum cathodes and stainless-steel anodes for 60 min without injecting oxidizing agent and solely based on in-situ ozone production. During the continuous mode test, the highest removal efficiencies achieved were 100 % for CN, 73 % for Ni, 100 % for Cu, and 78.8 % for Zn, all under identical operational parameters. These results confirm that ECOUV holds promise as a feasible approach for removing pollutants from the wastewater discharged by mineral processing facilities.

Optimizing Microservice Deployment in Edge Computing with Large Language Models: Integrating Retrieval Augmented Generation and Chain of Thought Techniques

Large Language Models (LLMs) have demonstrated impressive capabilities in autogenerating code based on natural language instructions provided by humans. We observed that in the microservice models of edge computing, the problem of deployment latency optimization can be transformed into an NP-hard mathematical optimization problem. However, in the real world, deployment strategies at the edge often require immediate updates, while human-engineered code tends to be lagging. To bridge this gap, we innovatively integrated LLMs into the decision-making process for microservice deployment. Initially, we constructed a private Retrieval Augmented Generation (RAG) database containing prior knowledge. Subsequently, we employed meticulously designed step-by-step inductive instructions and used the chain of thought (CoT) technique to enable the LLM to learn, reason, reflect, and regenerate. We decomposed the microservice deployment latency optimization problem into a collection of granular sub-problems (described in natural language), progressively providing instructions to the fine-tuned LLM to generate corresponding code blocks. The generated code blocks underwent integration and consistency assessment. Additionally, we prompted the LLM to generate code without the use of the RAG database for comparative analysis. We executed the aforementioned code and comparison algorithm under identical operational environments and simulation parameters, conducting rigorous result analysis. Our fine-tuned model significantly reduced latencies by 22.8% in handling surges in request flows, 37.8% in managing complex microservice types, and 39.5% in processing increased network nodes compared to traditional algorithms. Moreover, our approach demonstrated marked improvements in latency performance over LLMs not utilizing RAG technology and reinforcement learning algorithms reported in other literature. The use of LLMs also highlights the concept of symmetry, as the symmetrical structure of input-output relationships in microservice deployment models aligns with the LLM’s inherent ability to process and generate balanced and optimized code. Symmetry in this context allows for more efficient resource allocation and reduces redundant operations, further enhancing the model’s effectiveness. We believe that LLMs hold substantial potential in optimizing microservice deployment models.

Energy, exergy, exergoeconomic, economic, and environmental analyses and multi-objective optimization of a novel combined cooling and power system with dual-pressure Kalina cycle-absorption refrigeration

A novel combined cooling and power system, the dual-pressure Kalina cycle-absorption refrigeration (DPKC-AR-CCP), is proposed for the cascade utilization of waste heat from high-temperature flue gas and jacket water from internal combustion engines. A pneumatic booster pump unit is employed to increase the inlet pressure of the low-pressure expander, with heat generated during the compression process utilized for preheating the ammonia/water mixture, and exhaust gas from the low-pressure expander is combined with driving gas for absorption refrigeration. By integrating the first and second laws of thermodynamics with the SPECO Methodology, models for energy, exergy, exergoeconomy, economy, and environment of the DPKC-AR-CCP system are developed. A multi-objective optimization model is formulated with maximum exergy efficiency, minimum total exergy cost rate, and maximum annual equivalent carbon dioxide (CO2) emission reduction as objective functions. MATLAB software (combined with REFPROP software) is utilized for simulation and multi-objective optimization. The performance of each component under specific conditions is assessed, and a comparison with the simple absorption refrigeration/Kalina cogeneration system (AR/KC) highlights the advantages of the DPKC-AR-CCP system; an investigation into the effects of different operating parameters on performance is conducted. The results indicate that, under identical operational parameters, the DPKC-AR-CCP system exhibits a substantial increase in net output power (230.2 %), cooling capacity (98.7 %), and exergy efficiency (148.8 %) compared to the simple AR/KC system; payback period is reduced by 64.8 %; and annual equivalent CO2 emissions are decreased by 202.2 %. However, there is an increase in the total exergy cost rate by 90.5 %. The optimal concentration of ammonia/water is determined to be 0.816/0.184, with a heat exchanger outlet temperature of 341.07 K, driving pressure of 0.654 MPa, and low-pressure expander inlet pressure of 5.064 MPa. Correspondingly, the optimal exergy efficiency is 87.2 %, the annual reduction in CO2 emissions is 5.53 × 107 kg, and the total exergy cost rate is 288.48$/h.

Exergetic performance evaluation of louvered finned solar air heater: an experimental investigation

Solar energy is a promising source of renewable energy, and solar air heaters are an important application for utilizing this energy source. This study investigates the exergetic performance of a louvered fin solar air heater (LFSAH) through experimental analysis conducted during day time from 9 am to 3 pm under identical operating and metrological parameters. Exergy analysis based on the 2nd law of thermodynamics is used to assess the quality of exergy losses and useful energy output and is deemed suitable for LFSAH design. The study experimentally examines the exergetic performance of LFSAH with various fin spacings and compares the results with those of a plane solar air heater (PSAH). The exergy efficiency is optimized by considering the fin spacing (ranging from 2 to 5 cm) and mass flow rate (MFR) (ranging from 0.007 to 0.0158 kg/s) through an exergy analysis of internal and exterior exergy losses. Based on the result analysis, the LFSAH’s maximum exergy efficiency was achieved at 3.31% for a fin spacing of 2 cm and a MFR of 0.007 kg/s. The study found that incorporating louvered fins into the SAH substantially improves its exergetic performance compared to the PSAH.

Comparison of fatigue life behavior between deep groove radial ball bearings possessing conventional and micro-grooved outer races operating under dry condition

A comparative study on fatigue life of deep groove radial ball bearings possessing conventional and micro-grooved outer races by experimental investigation is discussed in this paper. This research has been carried out to explore and understand the fatigue life of a micro-grooved ball bearing (MGB) with a circumferential micro-groove on outer race by conducting long duration tests under dry condition (i.e. wiping out the applied grease from the races by using tissue paper and lint free cloth) and compare the results with same size SKF BB1B 420206 conventional bearing (CB) at the identical operating parameters. Frictional torque (FT), bulk temperature, and overall vibration level of the test bearings (CB and MGB) at the maximum load zone have been measured at 800 N ( pH = 1.7 GPa) radial load and 1800 rpm (4.2 m/s) for the entire duration (7.8 million revolutions) of the experiments. Comparison of the surface conditions of the bearing components by means of the captured scanning electron microscope (SEM) images, roundness and deviation in profile of the races measured by co-ordinate measuring machine (CMM), and photographs captured before and after the experiment indicates lesser damage of the MGB components as compared to the conventional cases. Moreover, the initiation of fatigue failure in CBs is faster as compared to the MGBs for the same test condition, indicating longer bearing life in MGBs as compared to the CBs.

Universal Single-Step Approach to the Immobilization of Cyclodextrins in a Supercritical Medium for Capturing Drug, Dye, and Metal Nanoclusters.

By utilizing nanoreactor-like structures, the immobilization of macromolecules such as calixarenes and cyclodextrins (CD) with bucket-like structures provides new possibilities for engineered surface-molecule systems. The practical use of any molecular system depends on the availability of a universal procedure for immobilizing molecules with torus-like structures on various surfaces while maintaining identical operating parameters. There are currently several steps, including toxic solvent-based approaches using modified β-CD to covalently attach to surfaces with multistep reactions. However, the existing multistep process results in molecular orientation, restricts the accessibility of the hydrophobic barrel of β-CD's for practical use, and is effectively unable to use the surfaces immobilized with β-CD for a variety of applications. In this study, it was demonstrated that β-CD attached to the oxide-based semiconductor and metal surfaces through a condensation reaction between the hydroxyl-terminated oxide-based semiconductor/metal oxide and β-CD in supercritical carbon dioxide (SCCO2) as a medium. The primary benefit of SCCO2-assisted grafting of unmodified β-CD on various oxide-based metal and semiconductor surfaces is that it is a simple, efficient, one-step process and that it is ligand-free, scalable, substrate-independent, and uses minimal energy. Various physical microscopy and chemical spectroscopic methods were used to analyze the grafted β-CD oligomers. The application of the grafted β-CD films was demonstrated by the immobilization of rhodamine B (RhB), a dye, and dopamine, a drug. The in situ nucleation and growth of silver nanoclusters (AgNCs) in the molecular systems were studied for antibacterial and tribological properties by utilizing the guest-host interaction ability of β-CD.

A minimal model for the influence of equilibrium positions on brake squeal

The phenomenon brake squeal has been an ongoing topic for decades, both in the automotive industry and in science. Although there is agreement on the excitation mechanism of brake squeal, namely self-excitation due to frictional forces between the disk and the pad, in the subject of squeal it is very complex to discover all relevant effects and to take them into account. Several of these problems are related to nonlinearities, for example, in the contact between pad and disk or drum or in the behavior of the brake pad material. One of these nonlinear effects, which has been almost completely neglected so far, is that the brake can engage, mainly due to the bushing and joint elements within the brake, different equilibrium positions. This in fact has serious influence on the noise behavior as shown in experimental studies. For example, it is observed in experiments that, despite identical operating parameters, squeal sometimes occurs and sometimes not. In initial experimental studies, this could be related to the engaged equilibrium position. Following these experimental studies, the present paper introduces a minimal model by extending the well-known minimal model by Hoffmann et al. by corresponding elements and nonlinearities allowing the system to engage different equilibrium positions. As will be presented, the stability behavior strongly depends on the engaged equilibrium position. Therefore, the minimal model represents the key experimentally observed issues. Additionally, a limit cycle behavior can also be observed.

Comprehensive analysis of NiFe2O4/MWCNTs nanocomposite to degrade a healthcare waste - tetracycline.

Tetracycline (TC), a commonly used antibiotic for studying bacterial illnesses in living organisms, poses a significant risk to the aquatic environment. Despite various conventional methods having been attempted to remove TC antibiotics from water solutions, they have not proven effective. Consequently, the focus of the research is on the photocatalytic degradation of TC. According to the research, MWCNTs were successfully incorporated into NiFe2O4 nanoparticles, which reduced the pace at which charge carriers recombined after joining with MWCNTs. Subsequently, the catalyst's efficacy was assessed in a batch reactor by analyzing the weight percentage change of the nanocomposite, the initial concentration of TC antibiotics, the effects of pH and contact time. The identical operational parameters were employed to investigate the degradation of TC using NiFe2O4 and MWCNTs as individual pure materials. The findings indicated that the photocatalytic process using NiFe2O4/MWCNTs achieved a degradation efficiency of 95.8% for TC at a pH value of 9. This result was obtained after a reaction time of 120 minutes, the concentration of TC solution was 10 mg L-1, with a nanocomposite dose of 0.6 g L-1 of TN 04 and 120 W m-2. The pseudo-first-order approach was used to estimate the rate at which TC degrades. After four consecutive uses, it was observed that the photocatalysts maintained their original properties, with only a slight decrease of approximately 2.4% in the removal efficiency. The study demonstrated that the NiFe2O4/MWCNTs nanocomposite exhibited considerable efficiency in degrading TC. Due to its simple manufacture and useful recovery, it has the potential to function well as a catalyst for the removal and degradation of pharmaceutical organic contaminants.

Performance improvement of a radial ball bearing using a micro-groove on stationary outer race

For achieving improved lubrication in a radial ball bearing (BB1B 420206), a circumferential micro-groove inside the stationary outer race has been conceived based on finite element analysis to facilitate the availability of grease and to reduce the stresses at the contacts and it has been fabricated to conduct the experiments. To understand the effect of this micro-groove filled with grease on the film formation, frictional torque, and bearing dynamics, experiments were performed for measuring these variables at different operating parameters ( pH = 0.35–1.2 GPa; speed = 1.4–4.2 m/s). Capacitance based approach, load cell, and miniature accelerometer have been employed to measure the film thickness, frictional load and vibrations, respectively. The results achieved with bearings with micro-groove on outer races have been compared with bearings having the conventional races at the identical operating parameters. Reductions of 14%–41% in vibrations, up to 11.2% increase in film thickness (i.e. 11% reduction in the capacitance), and in the range of 15%–30% reduction in the frictional torque have been obtained as compared to conventional bearing cases.

Tribological studies of low and high viscous oils lubricated heavily loaded textured point contacts under the reciprocating motion

The tribo-performance behaviors of lubricated textured point contacts have been explored herein at relatively high contact loads (up to 3 GPa) under reciprocating motion (0.2 and 0.4 m/s) employing low (ν@40 ℃ = 100 cSt) and high (ν@40 ℃ = 422 cSt) viscous oils. In this experimental study, two contacts (flat conventional surface vs. polished ball and textured flat surface vs. polished ball surface) have been created for the investigations of friction, wear, and contact potential (ability for film formation). It is found that in the presence of texture at the concentrated contacts, the coefficient of friction and wear have reduced considerably with high viscous oil irrespective of operating parameters. However, low viscous oil has yielded an increase in the wear under identical operating parameters. The contact potential (an indirect indication of film formation during the running-in period) in the presence of texture develops rapidly as compared to the conventional surface with both oils. It has demonstrated a reduction in the running-in period in the presence of textures at the contacts. The optical microscope images of worn surfaces of balls and tracks have also been presented for the quantification of wear and understanding of the associated mechanisms.

New insight into effect of antibiotics concentration and process configuration on the removal of antibiotics and relevant antibiotic resistance genes

To compare the performance and antibiotic-resistance character in different process configurations under different levels of antibiotics, anoxic/oxic-membrane bioreactors (MBR) 1#, MBR2# and a sequencing batch reactor (SBR) were operated with identical operating parameters. MBR1# and SBR were operated under high and increasing levels of antibiotics, MBR2# received constant and low concentration of antibiotics. Microbiological community and antibiotic resistance genes (ARGs) were investigated using 16S rDNA gene high-throughput sequencing and qPCR. More than 90% of penicillin and chlortetracycline were removed due to strong hydrolysis, followed by sulfamethoxazole (69.27%-86.25%) through biodegradation and norfloxacin (28.66%-53.86%) through adsorption. Process configuration affected total nitrogen removal more, while antibiotics concentration affected total phosphorus removal more. MBR1# outperformed SBR in reducing sulfamethoxazole, norfloxacin and ARGs due to the retention effect of the membrane module. Retention efficiency of ARGs in MBRs increased along the operation. Compared to the operational taxonomic unit (OTU) number before antibiotics addition, the OTU number in MBR1# and SBR decreased by 23.7% and 28.7%, while that in MBR2# kept relatively stable. Process configuration contributed to higher dissimilarity of microbial community than antibiotics concentration. The research provides an insight into the influence factors of antibiotics-containing wastewater treatment.

Identification of specialized pro-resolving mediator clusters from healthy adults after intravenous low-dose endotoxin and omega-3 supplementation: a methodological validation

Specialized pro-resolving mediator(s) (SPMs) are produced from the endogenous ω-3 polyunsaturated fatty acids (PUFA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), and accelerate resolution of acute inflammation. We identified specific clusters of SPM in human plasma and serum using LC-MS/MS based lipid mediator (LM) metabololipidomics in two separate laboratories for inter-laboratory validation. The human plasma cluster consisted of resolvin (Rv)E1, RvD1, lipoxin (LX)B4, 18-HEPE, and 17-HDHA, and the human serum cluster consisted of RvE1, RvD1, AT-LXA4, 18-HEPE, and 17-HDHA. Human plasma and serum SPM clusters were increased after ω-3 supplementation (triglyceride dietary supplements or prescription ethyl esters) and low dose intravenous lipopolysaccharide (LPS) challenge. These results were corroborated by parallel determinations with the same coded samples in a second, separate laboratory using essentially identical metabololipidomic operational parameters. In these healthy subjects, two ω-3 supplementation protocols (Study A and Study B) temporally increased the SPM cluster throughout the endotoxin-challenge time course. Study A and Study B were randomized and Study B also had a crossover design with placebo and endotoxin challenge. Endotoxin challenge temporally regulated lipid mediator production in human serum, where pro-inflammatory eicosanoid (prostaglandins and thromboxane) concentrations peaked by 8 hours post-endotoxin and SPMs such as resolvins and lipoxins initially decreased by 2 h and were then elevated at 24 hours. In healthy adults given ω-3 supplementation, the plasma concentration of the SPM cluster (RvE1, RvD1, LXB4, 18-HEPE, and 17-HDHA) peaked at two hours post endotoxin challenge. These results from two separate laboratories with the same samples provide evidence for temporal production of specific pro-resolving mediators with ω-3 supplementation that together support the role of SPM in vivo in inflammation-resolution in humans.

A 200-W permanent magnet Hall thruster discharge with graphite channel wall

A 200-W Hall thruster was designed using permanent magnets placing the axial maximum magnetic field outside of the channel, and the anode/gas distributor as an integrated U-shaped structure. A split structure is adopted for the discharge channel to conveniently change the wall material. With the initial conditions that the anode mass flow is maintained at 0.8 mg/s, 1.0 mg/s and 1.2 mg/s over a voltage range of 150–400 V (at 50 V intervals), the discharge properties were determined for the two thruster models with the channel walls composed of graphite and boron nitride (BN). The results demonstrate that under identical operating parameters, the properties of the thruster with the graphite channel walls are similar to the properties of the thruster with the BN channel walls. The maximum difference of the discharge current between the two wall materials is 6.2%; the maximum difference of the thrust and the specific impulse is 3.3%, and that of the anode efficiency is 1.7% (absolute value). These differences are smaller than the corresponding parameter differences observed from changing wall materials in other common Hall thrusters.

Flow distribution and pressure drop in UZ-type mini-hydrocyclone group arranged in compact parallel manifolds

Mini-hydrocyclones have commonly been used for high precision separation due to structural simplicity and having no moving parts. When they are placed in parallel, their throughput capacity can increase significantly for large industrial applications. Flow uniformity is closely correlated with separation performance. In this study, we developed a discrete model of a UZ-type mini-hydrocyclone group. What’s more, Separation experiments were performed for mini-hydrocyclone groups in ZZ-, UU-, and UZ-type arrangements. The results of the discrete model were compared to the experimental data. It was found that higher flow uniformity could be obtained with a lower split ratio or shorter inlet header length. Meanwhile, a larger head loss or flow distribution coefficient usually resulted in better uniformity in the outlet velocity of the manifold and less uniformity in the pressure drop. The UZ-type mini-hydrocyclone group was less maldistributed than the other arrangements under identical geometrical conditions and operational parameters. This study provides a guideline for designing arrangement of parallel mini-hydrocyclone groups in compact parallel manifolds.

Shelf life of fresh meat products under LED or fluorescent lighting

Enhanced pork loin chops, beef longissimus lumborum steaks, semimembranosus steaks (superficial and deep portions), ground beef, and ground turkey were displayed under light emitting diode (LED) and fluorescent (FLS) lighting in two multi-shelf, retail display cases with identical operating parameters. Visual and instrumental color, internal product temperature, case temperature, case cycling, thiobarbituric acid reactive substances (TBARS), and Enterobacteriaceae and aerobic plate counts were evaluated. Under LED, beef products (except the deep portion of beef semimembranosus steaks) showed less (P<0.05) visual discoloration. Pork loin chops had higher (P<0.05) L* values for LED lighting. Other than beef longissimus lumborum steaks, products displayed under LED lights had colder internal temperatures than products under FLS lights (P<0.05). Under LED, pork loin chops, ground turkey, and beef semimembranosus steaks had higher (P<0.05) values for TBARS. LED provides colder case and product temperatures, more case efficiency, and extended color life by at least 0.5d for longissimus and semimembranosus steaks; however, some LED cuts showed increased lipid oxidation.

HfC(310) high brightness sources for advanced imaging applications

The authors report on electron emission from HfC(310) operating in extended Schottky emission mode. Data are gathered from test stands as well as through operation in a commercial scanning electron microscope. Emitter end-form geometry consisted of rounded, via electrochemical etching, and truncated, via ion milling. The authors demonstrate high angular intensity operation of >60 mA/sr especially for the rounded end-form emitters. Advantages include robustness of the material, which is not reliant on material supply as is the case with standard ZrO/W(100) sources. Hence, operation is available over a much larger range of temperatures, fields, and potentially pressures. Operation in a commercial scanning electron microscope gave ten times higher beam currents for identical operational parameters over a standard Schottky source.

Simulation of the Post-combustion CO2 Capture with Aspen HysysTM Software: Study of Different Configurations of an Absorption-regeneration Process for the Application to Cement Flue Gases

Abstract The purpose of this study was to simulate, using Aspen Hysys TM with Amine Package and Kent-Eisenberg model for thermodynamic calculation, the post-combustion CO 2 capture and to compare different configurations of the absorption- regeneration process. In this paper, considering MEA 30% as solvent, we focused on three alternative configurations: the “Stripper Split Feed” (SSF), the “Lean Vapor Compressor” (LVC) and their combination. One of the specific aspects of this work is the fact that we considered cement flue gases, where the CO 2 content (from 20 to 30 wt.%) is higher than the one from conventional power plants (from 5 to 15 wt.%, generally considered in other studies) and which leads to different results in terms of energy savings. In a first step, the result of our simulation model was successfully validated with the use of literature results considering the St Marys cement plant in Canada as case study (CO 2 content of 24 mol.% in the gas to treat) and the classical configuration of the process. The boiler duty of the MEA 30% solvent calculated by our simulation model was equal to 3.71 GJ/tCO 2 (CO 2 capture rate of 85% with a purity of 98%) which is coherent with the literature value (3.68 GJ/tCO 2 ) considering identical operating parameters. The second step of the study was the simulation of this CO 2 capture process considering the same conditions (cement flue gases and MEA 30%) but investigating the three alternative configurations. Globally, this step highlighted that also for the CO 2 capture applied to cement flue gases significant regeneration energy savings (around 24%) are achievable thanks to the use of alternative configurations of the absorption-regeneration process. As perspectives, these simulation results will be compared to the ones obtained using the new Acid Gas Package developed by Aspen Hysys. Other innovative configurations (such as Stripper Overhead Compression “SOC”) will be simulated and the focus will be also put on other solvents (simples or activated solutions).

Radio Analytical Nondestructive Technique in Performance Evaluation of Organic Base Ion Exchange Resins Purolite NRW-6000 and Duolite A-378

Nondestructive radioanalytical technique using short lived isotopes 131I and 82Br was used as tracers to study the kinetics of iodide and bromide ion-isotopic exchange reactions. The kinetic data so obtained was used to evaluate the performance of organic base anion exchange resins Purolite NRW-6000 and Duolite A-378. It was observed that for iodide ion-isotopic exchange reaction performed at 40.0 °C using 1.000 g of ion exchange resins and 0.003 mol/L labeled iodide ion solution, the values of specific reaction rate (min-1), amount of iodide ion exchanged (mmol), initial rate of iodide ion exchange (mmol/min) and log Kd were calculated as 0.332, 0.582, 0.193 and 16.2 respectively for Purolite NRW-6000 resin, which was higher than the respective values of 0.210, 0.421, 0.088 and 14.7 as that obtained for Duolite A-378 resins. Also at a constant temperature of 40.0 °C, as the concentration of labeled iodide ion solution increases from 0.001 mol/L to 0.004 mol/L, the percentage of iodide ions exchanged increases from 74.68% to 79.48% using Purolite NRW-6000 resins and from 52.30% to 58.90% using Duolite A-378 resins. The overall results indicate superior performance of Purolite NRW-6000 resins over Duolite A-378 resins under identical operational parameters. It is expected here that the present technique can be extended further for characterization of different ion exchange resins which will further help in the selection of those reins for the specific industrial application.

Application of Nondestructive Radio Tracer Technique in Performance Evaluation of Anion Exchange Resins Duolite ARA-9366 and Duolite A-171

Radio analytical technique as a non-destructive technique was used in the present investigation to trace the kinetics of ion-isotopic exchange reaction taking place in Duolite ARA-9366 (nuclear grade) and Duolite A-171 (non-nuclear grade) anion exchange resins. The kinetics data suggest that during iodide ion-isotopic exchange reactions under identical experimental conditions of 40.00C, 1.000 g of ion exchange resins and 0.003 M labeled iodide ion solution, the values of specific reaction rate (min-1), amount of iodide ion exchanged (mmol), initial rate of iodide ion exchange (mmol/min) and log Kd were 0.176, 0.383, 0.067 and 7.8 respectively for Duolite ARA-9366 resin, which was higher than 0.142, 0.353, 0.050 and 7.0 respectively as that obtained for Duolite A-171 resins. Also it is observed that at a constant temperature of 40.0 °C, as the concentration of labeled iodide ion solution increases 0.001 M to 0.004 M, the percentage of iodide ions exchanged increases from 49.20% to 51.80% for Duolite ARA-9366 resins; and from 45.20% to 47.80% for Duolite A-171 resins. The similar trend was observed for the two resins during bromide ion-isotopic exchange reactions. The overall results indicate superior performance of Duolite ARA-9366 resins over Duolite A-171 resins under identical operational parameters.

Non Destructive Application of Radioactive Tracer Isotopes for Performance Evaluation of Industrial Grade Anion Exchange Resins Tulsion A-33 and Indion NSSR

The present study deals with non-destructive application of radioactive tracer isotopes to evaluate the performance of Tulsion A-33 (nuclear grade) and Indion NSSR (non-nuclear grade) anion exchange resins. The performance evaluation was done by carrying out the iodide and bromide ion-isotopic exchange reactions using the above resins. It was observed that at a constant temperature of 40.0 °C, as the concentration of labeled iodide ion solution increases 0.001 M to 0.004 M, the percentage of iodide ions exchanged increases from 58.0% to 64.0% for Tulsion A-33 resins; and from 48.4% to 50.8% for Indion NSSR resins. Similarly in case of bromide ion-isotopic exchange reaction under identical experimental conditions, the percentage of bromide ions exchanged increases from 45.6% to 50.4% for Tulsion A-33 resin; and from 39.8% to 44.6% for Indion NSSR resin. It was also observed that during iodide ion-isotopic exchange reaction at 40.0 °C, using 1.000 g of ion exchange resins and 0.003 M labeled ionic solution, using Tulsion A-33 resin the values of specific reaction rate (min-1), amount of iodide ion exchanged (mmol), initial rate of iodide ion exchange (mmol/min) and log Kd were 0.229, 0.469, 0.107 and 10.6 respectively, which was higher than the values of 0.167, 0.375, 0.063 and 7.6 respectively as obtained by using Indion NSSR resins under identical experimental conditions. The overall results indicate superior performance of Tulsion A-33 over Indion NSSR resin under identical operational parameters.