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Ki Won Song - One of the best experts on this subject based on the ideXlab platform.
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rheological evaluation of Petroleum Jelly as a base material in ointment and cream formulations linear viscoelastic behavior
2011Co-Authors: Eun Kyoung Park, Ki Won SongAbstract:ABSTRACT − The objective of the present study is to systematically characterize a linear viscoelastic behavior of petro-leum Jelly in small amplitude oscillatory shear flow fields correspondent to the rheological ground state. With this aim, usinga strain-controlled rheometer, the dynamic viscoelastic properties of commercially available Petroleum Jelly have been mea-sured at 37 o C (body temperature) over a wide range of angular frequencies at an extremely small strain amplitude of 0.1%. In this article, the linear viscoelastic behavior was reported in detail and then explained from a structural view-point ofPetroleum Jelly and discussed in depth with respect to the consumer’s requirements. Main findings obtained from this studycan be summarized as follows : (1) The storage modulus is always greater than the loss modulus over an entire range ofangular frequencies studied, meaning that the linear viscoelastic behavior of Petroleum Jelly is dominated by an elastic naturerather than a viscous nature. (2) Petroleum Jelly shows a desirable linear viscoelastic behavior with respect to the consumer’srequirements because it is undesirable for the product to flow down from the skin at an initial stage upon contact with thehuman skin. (3) A fractional derivative model shows an excellent applicability to describe a linear viscoelastic behavior ofPetroleum Jelly. However, this model should be used with a special caution because there exists no physical meaning forthe model parameters. (4) A modified form of the Cox-Merz rule gives a good ability to predict the relationship betweensteady shear flow properties (nonlinear behavior) and dynamic viscoelastic properties (linear behavior) for Petroleum Jelly.Key words
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original articles rheological evaluation of Petroleum Jelly as a base material in ointment and cream formulations linear viscoelastic behavior
2011Co-Authors: Eun Kyoung Park, Ki Won SongAbstract:The objective of the present study is to systematically characterize a linear viscoelastic behavior of Petroleum Jelly in small amplitude oscillatory shear flow fields correspondent to the rheological ground state. With this aim, using a strain-controlled rheometer, the dynamic viscoelastic properties of commercially available Petroleum Jelly have been measured at 37oC (body temperature) over a wide range of angular frequencies at an extremely small strain amplitude of 0.1 %. In this article, the linear viscoelastic behavior was reported in detail and then explained from a structural view-point of Petroleum Jelly and discussed in depth with respect to the consumer`s requirements. Main findings obtained from this study can be summarized as follows: (1) The storage modulus is always greater than the loss modulus over an entire range of angular frequencies studied, meaning that the linear viscoelastic behavior of Petroleum Jelly is dominated by an elastic nature rather than a viscous nature. (2) Petroleum Jelly shows a desirable linear viscoelastic behavior with respect to the consumer`s requirements because it is undesirable for the product to flow down from the skin at an initial stage upon contact with the human skin. (3) A fractional derivative model shows an excellent applicability to describe a linear viscoelastic behavior of Petroleum Jelly. However, this model should be used with a special caution because there exists no physical meaning for the model parameters. (4) A modified form of the Cox-Merz rule gives a good ability to predict the relationship between steady shear flow properties (nonlinear behavior) and dynamic viscoelastic properties (linear behavior) for Petroleum Jelly.
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rheological evaluation of Petroleum Jelly as a base material in ointment and cream formulations steady shear flow behavior
2010Co-Authors: Eun Kyoung Park, Ki Won SongAbstract:The objective of the present study is to systematically characterize a nonlinear rheological behavior of Petroleum Jelly (petrolatum) in steady shear flow fields correspondent to the spreading condition onto the human body. With this aim, using a strain-controlled rheometer, the steady shear flow properties of commercially available Petroleum Jelly have been measured at 37°C (body temperature) over a wide range of shear rates. In this article, the shear rate dependence of steady shear flow behavior was reported from the experimentally obtained data. In particular, the existence of a yield stress and a non-Newtonian flow behavior were discussed in depth with a special emphasis on their importance in actual application onto the human body. In addition, several inelastic-viscoplastic flow models including a yield stress parameter were employed to make a quantitative description of the steady shear flow behavior, and then the applicability of these models was examined in detail. Main findings obtained from this study can be summarized as follows: (1) Petroleum Jelly exhibits a finite magnitude of yield stress. The appearance of a yield stress is attributed to its three-dimensional network structure that can show a resistance to flow and plays an important role in determining a storage stability and sensory feature of the product. (2) Petroleum Jelly demonstrates a pronounced non-Newtonian shear-thinning flow behavior which is well described by a power-law equation and may be interpreted by the disruption of a crystalline network under the influence of mechanical shear deformation. This rheological feature enhances sensory qualities of pharmaceutical and cosmetic products in which Petroleum Jelly is used as a base material during their actual usage. (3) The Casson, Mizrahi-Berk, Heinz-Casson and Herschel-Bulkley models are all applicable and have almost an equivalent ability to quatitatively describe the steady shear flow behavior of Petroleum Jelly whereas the Bingham model does not give a good validity. Among these flow models, the Herschel-Bulkley model provides the best applicability.
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rheological evaluation of Petroleum Jelly as a base material in ointment and cream formulations with respect to rubbing onto the human body
2010Co-Authors: Eun Kyoung Park, Ki Won SongAbstract:The objective of the present study is to systematically characterize a nonlinear viscoelastic behavior of Petroleum Jelly in large amplitude oscillatory shear flow fields correspondent to the rubbing condition onto the human body. With this aim, using a strain-controlled rheometer, the dynamic viscoelastic properties of commercially available Petroleum Jelly have been measured at 37 o C (body temperature) over a wide range of strain amplitudes at several fixed angular frequencies. In this article, the strain amplitude dependence of the dynamic viscoelastic behavior was firstly reported in detail from the experimentally obtained data and then the results were explained from a structural view-point of Petroleum Jelly. Nextly, a comparison of elastic and viscous properties was made in small and large strain amplitude ranges and then these results were discussed in depth with a special emphasis on their importance in actual usage situations (i.e., rubbing onto the human body or skin). Main findings obtained from this study can be summarized as follows : (1) Both the storage modulus and loss modulus show a linear behavior only within an extremely small strain amplitude range ( ) and exhibit almost an equivalent strain limit of linear response ( ). (2) Both the storage modulus and loss modulus demonstrate a qualitatively similar strain-dependent nonlinear behavior (i.e., strain-thinning feature), even though the storage modulus shows a stronger dependence on strain amplitude than does the loss modulus. (3) As the strain amplitude is increased, the difference between the storage modulus and loss modulus is gradually decreased and subsequently a viscous property becomes superior to an elastic property at sufficiently large strain amplitude range. (4) A large amplitude oscillatory shear flow behavior can provide a plentiful information for a better understanding of the complicated rheological behavior of semi-solid ointment-like materials in their actual application onto the human body or skin.
Eun Kyoung Park - One of the best experts on this subject based on the ideXlab platform.
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rheological evaluation of Petroleum Jelly as a base material in ointment and cream formulations linear viscoelastic behavior
2011Co-Authors: Eun Kyoung Park, Ki Won SongAbstract:ABSTRACT − The objective of the present study is to systematically characterize a linear viscoelastic behavior of petro-leum Jelly in small amplitude oscillatory shear flow fields correspondent to the rheological ground state. With this aim, usinga strain-controlled rheometer, the dynamic viscoelastic properties of commercially available Petroleum Jelly have been mea-sured at 37 o C (body temperature) over a wide range of angular frequencies at an extremely small strain amplitude of 0.1%. In this article, the linear viscoelastic behavior was reported in detail and then explained from a structural view-point ofPetroleum Jelly and discussed in depth with respect to the consumer’s requirements. Main findings obtained from this studycan be summarized as follows : (1) The storage modulus is always greater than the loss modulus over an entire range ofangular frequencies studied, meaning that the linear viscoelastic behavior of Petroleum Jelly is dominated by an elastic naturerather than a viscous nature. (2) Petroleum Jelly shows a desirable linear viscoelastic behavior with respect to the consumer’srequirements because it is undesirable for the product to flow down from the skin at an initial stage upon contact with thehuman skin. (3) A fractional derivative model shows an excellent applicability to describe a linear viscoelastic behavior ofPetroleum Jelly. However, this model should be used with a special caution because there exists no physical meaning forthe model parameters. (4) A modified form of the Cox-Merz rule gives a good ability to predict the relationship betweensteady shear flow properties (nonlinear behavior) and dynamic viscoelastic properties (linear behavior) for Petroleum Jelly.Key words
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original articles rheological evaluation of Petroleum Jelly as a base material in ointment and cream formulations linear viscoelastic behavior
2011Co-Authors: Eun Kyoung Park, Ki Won SongAbstract:The objective of the present study is to systematically characterize a linear viscoelastic behavior of Petroleum Jelly in small amplitude oscillatory shear flow fields correspondent to the rheological ground state. With this aim, using a strain-controlled rheometer, the dynamic viscoelastic properties of commercially available Petroleum Jelly have been measured at 37oC (body temperature) over a wide range of angular frequencies at an extremely small strain amplitude of 0.1 %. In this article, the linear viscoelastic behavior was reported in detail and then explained from a structural view-point of Petroleum Jelly and discussed in depth with respect to the consumer`s requirements. Main findings obtained from this study can be summarized as follows: (1) The storage modulus is always greater than the loss modulus over an entire range of angular frequencies studied, meaning that the linear viscoelastic behavior of Petroleum Jelly is dominated by an elastic nature rather than a viscous nature. (2) Petroleum Jelly shows a desirable linear viscoelastic behavior with respect to the consumer`s requirements because it is undesirable for the product to flow down from the skin at an initial stage upon contact with the human skin. (3) A fractional derivative model shows an excellent applicability to describe a linear viscoelastic behavior of Petroleum Jelly. However, this model should be used with a special caution because there exists no physical meaning for the model parameters. (4) A modified form of the Cox-Merz rule gives a good ability to predict the relationship between steady shear flow properties (nonlinear behavior) and dynamic viscoelastic properties (linear behavior) for Petroleum Jelly.
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rheological evaluation of Petroleum Jelly as a base material in ointment and cream formulations steady shear flow behavior
2010Co-Authors: Eun Kyoung Park, Ki Won SongAbstract:The objective of the present study is to systematically characterize a nonlinear rheological behavior of Petroleum Jelly (petrolatum) in steady shear flow fields correspondent to the spreading condition onto the human body. With this aim, using a strain-controlled rheometer, the steady shear flow properties of commercially available Petroleum Jelly have been measured at 37°C (body temperature) over a wide range of shear rates. In this article, the shear rate dependence of steady shear flow behavior was reported from the experimentally obtained data. In particular, the existence of a yield stress and a non-Newtonian flow behavior were discussed in depth with a special emphasis on their importance in actual application onto the human body. In addition, several inelastic-viscoplastic flow models including a yield stress parameter were employed to make a quantitative description of the steady shear flow behavior, and then the applicability of these models was examined in detail. Main findings obtained from this study can be summarized as follows: (1) Petroleum Jelly exhibits a finite magnitude of yield stress. The appearance of a yield stress is attributed to its three-dimensional network structure that can show a resistance to flow and plays an important role in determining a storage stability and sensory feature of the product. (2) Petroleum Jelly demonstrates a pronounced non-Newtonian shear-thinning flow behavior which is well described by a power-law equation and may be interpreted by the disruption of a crystalline network under the influence of mechanical shear deformation. This rheological feature enhances sensory qualities of pharmaceutical and cosmetic products in which Petroleum Jelly is used as a base material during their actual usage. (3) The Casson, Mizrahi-Berk, Heinz-Casson and Herschel-Bulkley models are all applicable and have almost an equivalent ability to quatitatively describe the steady shear flow behavior of Petroleum Jelly whereas the Bingham model does not give a good validity. Among these flow models, the Herschel-Bulkley model provides the best applicability.
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rheological evaluation of Petroleum Jelly as a base material in ointment and cream formulations with respect to rubbing onto the human body
2010Co-Authors: Eun Kyoung Park, Ki Won SongAbstract:The objective of the present study is to systematically characterize a nonlinear viscoelastic behavior of Petroleum Jelly in large amplitude oscillatory shear flow fields correspondent to the rubbing condition onto the human body. With this aim, using a strain-controlled rheometer, the dynamic viscoelastic properties of commercially available Petroleum Jelly have been measured at 37 o C (body temperature) over a wide range of strain amplitudes at several fixed angular frequencies. In this article, the strain amplitude dependence of the dynamic viscoelastic behavior was firstly reported in detail from the experimentally obtained data and then the results were explained from a structural view-point of Petroleum Jelly. Nextly, a comparison of elastic and viscous properties was made in small and large strain amplitude ranges and then these results were discussed in depth with a special emphasis on their importance in actual usage situations (i.e., rubbing onto the human body or skin). Main findings obtained from this study can be summarized as follows : (1) Both the storage modulus and loss modulus show a linear behavior only within an extremely small strain amplitude range ( ) and exhibit almost an equivalent strain limit of linear response ( ). (2) Both the storage modulus and loss modulus demonstrate a qualitatively similar strain-dependent nonlinear behavior (i.e., strain-thinning feature), even though the storage modulus shows a stronger dependence on strain amplitude than does the loss modulus. (3) As the strain amplitude is increased, the difference between the storage modulus and loss modulus is gradually decreased and subsequently a viscous property becomes superior to an elastic property at sufficiently large strain amplitude range. (4) A large amplitude oscillatory shear flow behavior can provide a plentiful information for a better understanding of the complicated rheological behavior of semi-solid ointment-like materials in their actual application onto the human body or skin.
John W. Nicholson - One of the best experts on this subject based on the ideXlab platform.
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the effect of Petroleum Jelly light cured varnish and different storage media on the flexural strength of glass ionomer dental cements
2016Co-Authors: Kristina Gorseta, Domagoj Glavina, Tomislav Skrinjaric, Beata Czarnecka, John W. NicholsonAbstract:This study determined the influence of coating with either Petroleum Jelly or light-cured varnish and storage medium on the flexural strength of glass-ionomer cements (GIC). The flexural strength of two glass-ionomer cements (Fuji Equia Fil and Ketac Molar Aplicap) was measured. Specimens (2 × 2 × 25 mm) were prepared in three groups: uncoated, coated with Petroleum Jelly, or coated with light-cured varnish (EquiaCoat) cured for 20 s using a cure lamp (Bluephase G2, Ivoclar Vivadent, Schaan, Liechtenstein). Specimens were stored for 1 week at 37 °C in water, artificial saliva or 20 mmol dm-3 lactic acid, then flexural strength was determined in 3-pont bend. Data were analyzed by ANOVA and Tukey HSD post hoc test (p < 0.05). In addition, the mold was filled with water and the temperature change caused by the cure lamp was measured with a thermocouple. For both materials, storage in water gave the lowest flexural strength. It was slightly higher in either saliva or lactic acid, and was improved by coating in Petroleum Jelly. Specimens coated with light-cured varnish, that also involved heating with a cure lamp, gave the highest flexural strength. The heating effect of the lamp was demonstrated by the temperature rise in the water in the mold after light exposure from 21.9 (± 1.0) °C to 26.8 (± 1.0) °C. hence, sealing of GIC from aqueous media improves flexural strength. The cure lamp emitted heat, which may enhance the flexural strength of specimens coated with light-cured varnish.
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The effect of Petroleum Jelly, light-cured varnish and different storage media on the flexural strength of glass ionomer dental cements
2016Co-Authors: Kristina Gorseta, Domagoj Glavina, Tomislav Skrinjaric, Beata Czarnecka, John W. NicholsonAbstract:This study determined the influence of coating with either Petroleum Jelly or light-cured varnish and storage medium on the flexural strength of glass-ionomer cements (GIC). The flexural strength of two glass-ionomer cements (Fuji Equia Fil and Ketac Molar Aplicap) was measured. Specimens (2 × 2 × 25 mm) were prepared in three groups: uncoated, coated with Petroleum Jelly, or coated with light-cured varnish (EquiaCoat) cured for 20 s using a cure lamp (Bluephase G2, Ivoclar Vivadent, Schaan, Liechtenstein). Specimens were stored for 1 week at 37 °C in water, artificial saliva or 20 mmol dm−3 lactic acid, then flexural strength was determined in 3-pont bend. Data were analyzed by ANOVA and Tukey HSD post hoc test (p
N K Geddes - One of the best experts on this subject based on the ideXlab platform.
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a prospective single blind randomized controlled trial of Petroleum Jelly vaseline for recurrent paediatric epistaxis
2004Co-Authors: S Loughran, Ekaterini Spinou, W A Clement, R Cathcart, Haytham Kubba, N K GeddesAbstract:The aim of the study was to determine if Petroleum Jelly was an effective treatment for paediatric epistaxis. A single-blind, prospective, randomized controlled trial was undertaken in an otolaryngology outpatient clinic of a paediatric hospital from March 2001 to March 2002. A total of 105 children referred with recurrent epistaxis were randomized into the study, 52 into the treatment arm and 53 into the control arm. Children in the treatment arm applied Vaseline twice a day bilaterally for 4 weeks and were monitored for any bleeds for the next 4 weeks. Children in the control arm were simply given an 8-week appointment and the number of bleeds were monitored for the 4 weeks prior to their appointment. The outcome measure was the proportion of children in each group without nosebleeds in the preceding 4 weeks. Both groups were equally distributed in age, duration of symptoms and duration of each bleed. Fourteen of 51 (27.5%) patients of the treatment arm and 18 of 53 (34%) of the control arm did not bleed in the 4 weeks before review (chi-square test, P = 0.472). It can be concluded that Vaseline alone confers no benefit over simple observation in recurrent childhood epistaxis.
Gabor Cserni - One of the best experts on this subject based on the ideXlab platform.
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Petroleum Jelly induced penile paraffinoma with inguinal
2013Co-Authors: Istvan Sejben, Andras Racz, Mihaly Svebis, Marta Patyi, Gabor CserniAbstract:Chronic granulomatous inflammation may develop after injecting foreign oily substances into the penis. The disorder affects mainly the site of administration, but regional lymphadenopathy or even systemic disease can occur. We present a 39-year-old man with Petroleum Jelly-induced penile lesion and unilateral inguinal lymphadenitis mimicking incarcerated inguinal hernia. At hernioplasty no hernial sac was found, but enlarged lymph nodes suspicious for malignancy were identified. The histopathologic findings of these nodes were consistent with mineral oil granuloma. Paraffinoma of the male genitalia can cause various clinical features posing a differential diagnostic dilemma. Regional lymphadenitis may be the main clinical characteristic. Patient’s history, physical and histopathological examination are required to establish the diagnosis.
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Petroleum Jelly induced penile paraffinoma with inguinal lymphadenitis mimicking incarcerated inguinal hernia
2012Co-Authors: Istvan Sejben, Andras Racz, Mihaly Svebis, Marta Patyi, Gabor CserniAbstract:Chronic granulomatous inflammation may develop after injecting foreign oily substances into the penis. The disorder affects mainly the site of administration, but regional lymphadenopathy or even systemic disease can occur. We present a 39-year-old man with Petroleum Jelly-induced penile lesion and unilateral inguinal lymphadenitis mimicking incarcerated inguinal hernia. At hernioplasty no hernial sac was found, but enlarged lymph nodes suspicious for malignancy were identified. The histopathologic findings of these nodes were consistent with mineral oil granuloma. Paraffinoma of the male genitalia can cause various clinical features posing a differential diagnostic dilemma. Regional lymphadenitis may be the main clinical characteristic. Patient’s history, physical and histopathological examination are required to establish the diagnosis.