The Experts below are selected from a list of 309 Experts worldwide ranked by ideXlab platform
Marieclaire Hennion - One of the best experts on this subject based on the ideXlab platform.
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optimization of the class selective extraction of triazines from aqueous samples using a molecularly imprinted polymer by a comprehensive approach of the retention mechanism
Journal of Chromatography A, 2003Co-Authors: Florence Chapuis, Valerie Pichon, F Lanza, S Sellergren, Marieclaire HennionAbstract:Direct, selective solid-phase extraction of triazines from aqueous samples is presented using a molecularly imprinted polymer (MIP) made with terbutylazine as template molecule. After optimization of the steps of the procedure, 14 triazines including degradation products were studied and satisfactory extraction recoveries were obtained except for thiotriazines. By comparing results obtained with the terbutylazine MIP and a similar non-imprinted polymer, it was determined that retention was achieved via specific interactions except for hydroxyterbutylazine. Selectivity of the extraction procedure was also verified by applying the MIP for the extraction of phenylureas that were not retained on it. The effects of the charge distribution and of molecular volume of the triazines (obtained by molecular modeling) on the selectivity of interactions between the analytes and the MIP were studied. However, when the optimized procedure was applied to real samples, low extraction recoveries were obtained due to strong matrix effects: ion-exchange occurs between the carboxylate groups of the MIP and the ionic species of the sample, that prevents subsequent specific interactions. By introducing an Acid Wash step, the procedure was successfully applied for the class-selective extraction of triazines from industrial effluent and surface water samples. Finally, increased extraction recoveries were achieved for the polar degradation products of triazines by using a mixed-phase composed of a polymeric sorbent and the MIP.
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Molecularly imprinted polymers : optimization of the class-selective extraction of triazines from aqueous samples by a comprehensive approach of the retention mechanism
Journal of Chromatography A, 2003Co-Authors: Florence Chapuis, Valerie Pichon, Francesca Lanza - Sellergren, Börje Sellergren, Marieclaire HennionAbstract:Direct, selective solid-phase extraction of triazines from aqueous samples is presented using a molecularly imprinted polymer (MIP) made with terbutylazine as template molecule. After optimization of the steps of the procedure, 14 triazines including degradation products were studied and satisfactory extraction recoveries were obtained except for thiotriazines. By comparing results obtained with the terbutylazine MIP and a similar non-imprinted polymer, it was determined that retention was achieved via specific interactions except for hydroxyterbutylazine. Selectivity of the extraction procedure was also verified by applying the MIP for the extraction of phenylureas that were not retained on it. The effects of the charge distribution and of molecular volume of the triazines (obtained by molecular modeling) on the selectivity of interactions between the analytes and the MIP were studied. However, when the optimized procedure was applied to real samples, low extraction recoveries were obtained due to strong matrix effects: ion-exchange occurs between the carboxylate groups of the MIP and the ionic species of the sample, that prevents subsequent specific interactions. By introducing an Acid Wash step, the procedure was successfully applied for the class-selective extraction of triazines from industrial effluent and surface water samples. Finally, increased extraction recoveries were achieved for the polar degradation products of triazines by using a mixed-phase composed of a polymeric sorbent and the MIP.
R T Dingwell - One of the best experts on this subject based on the ideXlab platform.
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the association between bulk tank milk analysis for raw milk quality and on farm management practices
Preventive Veterinary Medicine, 2010Co-Authors: Ahmed M Elmoslemany, G P Keefe, Ian R Dohoo, J J Wichtel, Henrik Stryhn, R T DingwellAbstract:Our objective was to determine the risk factors associated with bacteriological quality of bulk tank milk. Bulk tank milk samples were collected from all Prince Edward Island dairy herds (n = 235) from March 2005 to March 2007. Biweekly total bacterial, preliminary incubation, laboratory pasteurization, and coliform counts were conducted using a Petrifilm culture system. Data for on-farm risk factors were collected via a mail-out survey which consisted of 4 main sections: (1) general farm demographics and management, (2) cow cleanliness and hygiene, (3) milking procedures and mastitis control, and (4) equipment maintenance and cleaning. Of 235 producers, 153 completed the mail-out survey giving a response rate of 65%. Both total aerobic and preliminary incubation counts were positively associated with the amount of soiling on the teats prior to udder preparation, manual cleaning of the bulk tank, and the use of a specific type of detergent. Additionally, various methods of premilking udder preparation were important, with pre-dip followed by drying being superior to other methods in reducing the bacterial counts. The laboratory pasteurization count was positively associated with the presence of a plate cooler and inadequate frequency of Acid Wash, whereas having a water purification system was negatively associated with laboratory pasteurization count. Finally, coliform count was negatively associated with clipping udder hair and automated Washing of the bulk tank, whereas increasing herd size and inadequate frequency of Acid Wash were risk factors. Season was a significant predictor for all bacterial counts with the lowest counts tending to occur in winter.
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the association between bulk tank milk analysis for raw milk quality and on farm management practices
Preventive Veterinary Medicine, 2010Co-Authors: Ahmed M Elmoslemany, G P Keefe, Ian R Dohoo, J J Wichtel, Henrik Stryh, R T DingwellAbstract:Our objective was to determine the risk factors associated with bacteriological quality of bulk tank milk. Bulk tank milk samples were collected from all Prince Edward Island dairy herds (n = 235) from March 2005 to March 2007. Biweekly total bacterial, preliminary incubation, laboratory pasteurization, and coliform counts were conducted using a Petrifilm culture system. Data for on-farm risk factors were collected via a mail-out survey which consisted of 4 main sections: (1) general farm demographics and management, (2) cow cleanliness and hygiene, (3) milking procedures and mastitis control, and (4) equipment maintenance and cleaning. Of 235 producers, 153 completed the mail-out survey giving a response rate of 65%. Both total aerobic and preliminary incubation counts were positively associated with the amount of soiling on the teats prior to udder preparation, manual cleaning of the bulk tank, and the use of a specific type of detergent. Additionally, various methods of premilking udder preparation were important, with pre-dip followed by drying being superior to other methods in reducing the bacterial counts. The laboratory pasteurization count was positively associated with the presence of a plate cooler and inadequate frequency of Acid Wash, whereas having a water purification system was negatively associated with laboratory pasteurization count. Finally, coliform count was negatively associated with clipping udder hair and automated Washing of the bulk tank, whereas increasing herd size and inadequate frequency of Acid Wash were risk factors. Season was a significant predictor for all bacterial counts with the lowest counts tending to occur in winter.
Florence Chapuis - One of the best experts on this subject based on the ideXlab platform.
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optimization of the class selective extraction of triazines from aqueous samples using a molecularly imprinted polymer by a comprehensive approach of the retention mechanism
Journal of Chromatography A, 2003Co-Authors: Florence Chapuis, Valerie Pichon, F Lanza, S Sellergren, Marieclaire HennionAbstract:Direct, selective solid-phase extraction of triazines from aqueous samples is presented using a molecularly imprinted polymer (MIP) made with terbutylazine as template molecule. After optimization of the steps of the procedure, 14 triazines including degradation products were studied and satisfactory extraction recoveries were obtained except for thiotriazines. By comparing results obtained with the terbutylazine MIP and a similar non-imprinted polymer, it was determined that retention was achieved via specific interactions except for hydroxyterbutylazine. Selectivity of the extraction procedure was also verified by applying the MIP for the extraction of phenylureas that were not retained on it. The effects of the charge distribution and of molecular volume of the triazines (obtained by molecular modeling) on the selectivity of interactions between the analytes and the MIP were studied. However, when the optimized procedure was applied to real samples, low extraction recoveries were obtained due to strong matrix effects: ion-exchange occurs between the carboxylate groups of the MIP and the ionic species of the sample, that prevents subsequent specific interactions. By introducing an Acid Wash step, the procedure was successfully applied for the class-selective extraction of triazines from industrial effluent and surface water samples. Finally, increased extraction recoveries were achieved for the polar degradation products of triazines by using a mixed-phase composed of a polymeric sorbent and the MIP.
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Molecularly imprinted polymers : optimization of the class-selective extraction of triazines from aqueous samples by a comprehensive approach of the retention mechanism
Journal of Chromatography A, 2003Co-Authors: Florence Chapuis, Valerie Pichon, Francesca Lanza - Sellergren, Börje Sellergren, Marieclaire HennionAbstract:Direct, selective solid-phase extraction of triazines from aqueous samples is presented using a molecularly imprinted polymer (MIP) made with terbutylazine as template molecule. After optimization of the steps of the procedure, 14 triazines including degradation products were studied and satisfactory extraction recoveries were obtained except for thiotriazines. By comparing results obtained with the terbutylazine MIP and a similar non-imprinted polymer, it was determined that retention was achieved via specific interactions except for hydroxyterbutylazine. Selectivity of the extraction procedure was also verified by applying the MIP for the extraction of phenylureas that were not retained on it. The effects of the charge distribution and of molecular volume of the triazines (obtained by molecular modeling) on the selectivity of interactions between the analytes and the MIP were studied. However, when the optimized procedure was applied to real samples, low extraction recoveries were obtained due to strong matrix effects: ion-exchange occurs between the carboxylate groups of the MIP and the ionic species of the sample, that prevents subsequent specific interactions. By introducing an Acid Wash step, the procedure was successfully applied for the class-selective extraction of triazines from industrial effluent and surface water samples. Finally, increased extraction recoveries were achieved for the polar degradation products of triazines by using a mixed-phase composed of a polymeric sorbent and the MIP.
Ahmed M Elmoslemany - One of the best experts on this subject based on the ideXlab platform.
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the association between bulk tank milk analysis for raw milk quality and on farm management practices
Preventive Veterinary Medicine, 2010Co-Authors: Ahmed M Elmoslemany, G P Keefe, Ian R Dohoo, J J Wichtel, Henrik Stryhn, R T DingwellAbstract:Our objective was to determine the risk factors associated with bacteriological quality of bulk tank milk. Bulk tank milk samples were collected from all Prince Edward Island dairy herds (n = 235) from March 2005 to March 2007. Biweekly total bacterial, preliminary incubation, laboratory pasteurization, and coliform counts were conducted using a Petrifilm culture system. Data for on-farm risk factors were collected via a mail-out survey which consisted of 4 main sections: (1) general farm demographics and management, (2) cow cleanliness and hygiene, (3) milking procedures and mastitis control, and (4) equipment maintenance and cleaning. Of 235 producers, 153 completed the mail-out survey giving a response rate of 65%. Both total aerobic and preliminary incubation counts were positively associated with the amount of soiling on the teats prior to udder preparation, manual cleaning of the bulk tank, and the use of a specific type of detergent. Additionally, various methods of premilking udder preparation were important, with pre-dip followed by drying being superior to other methods in reducing the bacterial counts. The laboratory pasteurization count was positively associated with the presence of a plate cooler and inadequate frequency of Acid Wash, whereas having a water purification system was negatively associated with laboratory pasteurization count. Finally, coliform count was negatively associated with clipping udder hair and automated Washing of the bulk tank, whereas increasing herd size and inadequate frequency of Acid Wash were risk factors. Season was a significant predictor for all bacterial counts with the lowest counts tending to occur in winter.
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the association between bulk tank milk analysis for raw milk quality and on farm management practices
Preventive Veterinary Medicine, 2010Co-Authors: Ahmed M Elmoslemany, G P Keefe, Ian R Dohoo, J J Wichtel, Henrik Stryh, R T DingwellAbstract:Our objective was to determine the risk factors associated with bacteriological quality of bulk tank milk. Bulk tank milk samples were collected from all Prince Edward Island dairy herds (n = 235) from March 2005 to March 2007. Biweekly total bacterial, preliminary incubation, laboratory pasteurization, and coliform counts were conducted using a Petrifilm culture system. Data for on-farm risk factors were collected via a mail-out survey which consisted of 4 main sections: (1) general farm demographics and management, (2) cow cleanliness and hygiene, (3) milking procedures and mastitis control, and (4) equipment maintenance and cleaning. Of 235 producers, 153 completed the mail-out survey giving a response rate of 65%. Both total aerobic and preliminary incubation counts were positively associated with the amount of soiling on the teats prior to udder preparation, manual cleaning of the bulk tank, and the use of a specific type of detergent. Additionally, various methods of premilking udder preparation were important, with pre-dip followed by drying being superior to other methods in reducing the bacterial counts. The laboratory pasteurization count was positively associated with the presence of a plate cooler and inadequate frequency of Acid Wash, whereas having a water purification system was negatively associated with laboratory pasteurization count. Finally, coliform count was negatively associated with clipping udder hair and automated Washing of the bulk tank, whereas increasing herd size and inadequate frequency of Acid Wash were risk factors. Season was a significant predictor for all bacterial counts with the lowest counts tending to occur in winter.
Robe E Graves - One of the best experts on this subject based on the ideXlab platform.
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mathematical modeling and cycle time reduction of deposit removal from stainless steel pipeline during cleaning in place of milking system with electrolyzed oxidizing water
Journal of Food Engineering, 2016Co-Authors: X Wang, Ali Demirci, Virendra M Puri, Robe E GravesAbstract:The safety of raw milk largely depends on using a clean milking system during the milk production. The milking system cleaning process widely used on dairy farms is a highly automated process called cleaning-in-place (CIP), which comprises of four cycles: i) warm water rinse; ii) alkaline Wash; iii) Acid Wash; and iv) sanitizing rinse before the next milking event. Electrolyzed oxidizing (EO) water is an emerging technology, which consists of Acidic and alkaline solutions by the electrodialysis of dilute sodium chloride solution. Previous studies in our lab showed that EO water can be an alternative for milking system CIP. Despite the progress made to enhance the CIP performance and evaluate alternative CIPs, the mechanisms behind the cleaning processes were still largely unclear. Therefore, this study was undertaken to evaluate the deposit removal rate during the EO water CIP process using a stainless steel surface evaluation simulator. Deposit removal data from the simulator formed the basis for developing mathematical models to describe the deposit removal process during the CIP process with EO water. Stainless steel straight pipe specimens were placed at the end of undisturbed entrance length along the simulator pipeline. The mass of milk deposits on the inner surfaces of the specimens were measured using a high precision balance after the initial soiling, and then after certain time durations within the warm water rinse, alkaline Wash, and Acid Wash cycles. A unified first order deposit removal rate model dependent on nth power of remaining deposit mass was used for all three cycles. ATP bioluminescence method was also used as a validation approach at the end of each CIP cycle. Experimental results showed that the milk deposit on the inner surfaces of the specimens was removed rapidly by the warm water rinse within 10 s of rinse time. For the alkaline and Acid Wash cycles, the co-existence of a fast deposit removal at the beginning of the Wash cycle and a slow deposit removal throughout the entire Wash cycle was inferred. The proposed models matched the experimental data with small root mean square errors (0.23 mg/[(mg) (m2)] and 0.07 mg/[(mg) (m2)] for the upstream and downstream locations, respectively) and satisfactory percent error differences (3.67% and 0.93% for the upstream and downstream locations, respectively). Based on the experimental data and the proposed models, the time duration of the CIP process was shortened by 55% (10 s warm water rinse, 3 min alkaline Wash and 6 min Acid Wash) and validated, which yielded an average deposit of 0.28 mg/[(mg) (m2)] at the end of the CIP as compared with that of 0.29 mg/[(mg) (m2)] at the end of the original CIP, to achieve a satisfactory CIP performance for the simulator.
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evaluation of blended electrolyzed oxidizing water based cleaning in place cip technique using a laboratory scale milking system
Transactions of the ASABE, 2016Co-Authors: X Wang, Ali Demirci, Virendra M Puri, Robe E GravesAbstract:Abstract. Milk safety is a food safety concern in the U.S., and the cleanliness of on-farm milking systems directly affects raw milk quality. The conventionally accepted four-step procedure for milking system cleaning-in-place (CIP) includes: (1) warm water rinse, (2) alkaline Wash, (3) Acid Wash, and (4) sanitizing rinse prior to the next milking event. Electrolyzed oxidizing (EO) water is an emerging technology that generates Acidic and alkaline EO water by electrodialysis of a dilute sodium chloride solution. Previous studies have shown that EO water can be an alternative for conventional milking system CIP, both in pilot-scale milking systems and on commercial dairy farms. Recently, a one-step cleaning process has been adopted on an increasing number of dairy farms that combines the alkaline Wash and Acid Wash to save chemical expenditure, water usage, energy cost, and time. By blending Acidic EO water with alkaline EO water, a less corrosive but still effective blended EO water solution can be produced. Therefore, this study was undertaken to evaluate the blended EO water solution for one-step CIP using a pilot-scale milking system and compare the CIP effectiveness and cost with commercial one-step CIP chemicals. A Box-Behnken three-factor response surface method was used to determine the optimal cleaning time, the starting temperature of the blended EO water solution, and the Acidic EO water percentage. Two commercial one-step CIP chemicals were used for comparisons of CIP effectiveness and cost. Results showed that a cleaning time of 17 min, a starting temperature of 59°C, and an Acidic EO water percentage of 60% in the blended EO water solution could achieve the required 100% CIP performance and was comparable to the commercial one-step cleaning chemicals. Moreover, it was determined that the operating cost of one complete cleaning cycle, including the material cost and energy consumption, using blended EO water was 80% lower than using the commercial one-step cleaning chemicals. Overall, this study demonstrated that blended EO water has potential to be adapted as an alternative for one-step CIP for milking systems and possibility other food processing equipment.
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evaluation of electrolyzed oxidizing water for cleaning in place of on farm milking systems
American Society of Agricultural and Biological Engineers Annual International Meeting 2013, 2013Co-Authors: X Wang, Ali Demirci, Robe E Graves, S R S Dev, Virendra M PuriAbstract:Abstract. The cleanliness and sanitation of the on-farm milking system directly affects raw milk quality. A four-step procedure is generally accepted for cleaning-in-place (CIP) of milking systems, which involves water rinse, hot alkaline Wash, warm Acid Wash and sanitizing Wash. The electrolyzed oxidizing (EO) water is a technology in which Acidic EO water and alkaline EO water solutions are generated separately by electrolyzing weak sodium chloride solution. As these two solutions match the basic requirements for the CIP of milking systems, it was proposed that the EO water can be used as a cleaning and sanitizing agent for CIP of milking systems. Previous studies demonstrated that the utilization of the EO water CIP provided equal or better results than the conventional CIP in a pilot-scale milking system. This research was undertaken to evaluate, assess, and validate the EO water technology on a commercial dairy farm compared with the conventional CIP. Results from the Adenosine Tri-Phosphate (ATP) bioluminescence method showed that the EO water CIP provided equal to or better results compared with conventional CIP for most of the sampling locations and other system components. Moreover, results for bacterial presence corresponded with the ATP bioluminescence results, indicating the capability of using EO water for the cleaning and sanitizing of on-farm milking systems. For one complete CIP operational process, it was estimated that the cost of using the EO water CIP is lower than using the conventional CIP by about 25%. Based on the technical performance and economic analyses, this study showed that the EO water has the potential to be adapted as an alternative CIP of on-farm milking systems.
