U.S. consumers are the largest contributors to food waste generation (FWG), but few models have e... more U.S. consumers are the largest contributors to food waste generation (FWG), but few models have explained how households waste food. This study examines how discrete-event simulation (DES) can identify areas for reducing FWG through packaging and consumer milk consumption behavioral changes. Household model parameters included: amount and type of consumption, type and number of containers bought, buying behavior, and shelf life of milk. Simulations comparing the purchase of quart, half gallon, and gallon milk containers were run for 10,000 days to identify which package type reduced waste for 50 1, 2 and 4-person households. Based on consumption averages from the U.S. National Dairy Council, results suggest that if 1 and 4-person households change their purchasing behavior from 1 half-gallon to 1 quart and 2 gallons to 3 half-gallons, they can reduce their greenhouse gas (GHG) emissions from milk consumption by 33% and 12%, respectively, without reducing their total milk consumption...
The research on a self-decontaminating surface has received significant attention because of the ... more The research on a self-decontaminating surface has received significant attention because of the growth of pathogenic microorganisms on surfaces. In this study, a novel and simple technique for producing an active surface with antimicrobial functionality is demonstrated. A tethering platform was developed by grafting the biocide ampicillin (Amp) to a nanoclay and dispersing the nanoclay in a UV-curable acrylate coating applied on polypropylene films as the substrate. A coupling agent, [3-(glycidyloxy)propyl]trimethoxysilane, was used as a linker between the nanoclay and Amp. The Amp-functionalized clay was further modified with an organic surfactant to improve the compatibility with the coating. Several characterization assays, such as Fourier infrared transform analysis, thermogravimetric analysis, and X-ray diffraction, were conducted to confirm the presence of Amp in the nanoclay. Transmission electron microscopy images revealed that the clay particles were well dispersed in the coating and had a partial exfoliated morphology. The active coating surface was effective in inhibiting the growth of Gram-positive Listeria monocytogenes and Gram-negative Salmonella Typhimurium via contact. These findings suggest the potential for the development of active surfaces with the implementation of nanotechnology to achieve diverse functionalities.
Container-grown woody ornamentals were irrigated with 4 treatments based on daily water use (DWU)... more Container-grown woody ornamentals were irrigated with 4 treatments based on daily water use (DWU) to study the impact of irrigation regime on plant growth, leachate electrical conductivity and pH, and runoff water volume and nutrient content. Hibiscus syriacus ‘Bricotts’, Euonymus alatus ‘Select’, Weigela florida ‘Alexandra’, and Spiraea japonica ‘Yan’ were grown in 10.2-L (#3) containers and subject to four overhead irrigation treatments: 1) irrigation scheduled to replace 100% DWU per application (100DWU); 2) irrigation alternating every other application with 100% replacement of DWU and 75% DWU the following application (100-75); 3) irrigation scheduled on a three-application cycle replacing 100% DWU followed by two applications replacing 75% DWU (100-75-75); and 4) irrigation scheduled on a four-application cycle replacing 100% DWU followed by three application replacing 75% DWU (100-75-75-75). Container substrate consisted of 85% pine bark: 15% peatmoss (vol: vol). Plants were ...
Containers made from natural fiber and recycled plastic are marketed as sustainable substitutes f... more Containers made from natural fiber and recycled plastic are marketed as sustainable substitutes for traditional plastic containers in the nursery industry. However, growers' acceptance of alternative containers is limited by the lack of information on how alternative containers impact plant growth and water use (WU). We conducted experiments in Michigan, Kentucky, Tennessee, Mississippi, and Texas to test plant growth and WU in five different alternative containers under nursery condition. In 2011, 'Roemertwo' wintercreeper (Euonymus fortunei) were planted in three types of #1 (%1 gal) containers 1) black plastic (plastic), 2) wood pulp (WP), and 3) recycled paper (KF). In 2012, 'Green Velvet' boxwood (Buxus sempervirens · B. microphylla siebold var. koreana) was evaluated in 1) plastic, 2) WP, 3) fabric (FB), and 4) keratin (KT). In 2013, 'Dark Knight' bluebeard (Caryopteris ·clandonensis) was evaluated in 1) plastic, 2) WP, and 3) coir fiber (Coir). Pla...
Ultraviolet-visible (UV-Vis) spectroscopy methodology was developed and utilized for the in situ ... more Ultraviolet-visible (UV-Vis) spectroscopy methodology was developed and utilized for the in situ nanoscale measurement of the size of mineral clay agglomerates in various liquid suspensions. The clays studied were organomodified and unmodified montmorillonite clays (I.44p, Cloisite 93a, and PGN). The methodology was compared and validated against dynamic light scattering (DLS) analysis. The method was able to measure clay agglomerates in solvents in situations where DLS analysis was unsuccessful due to the shapes, polydispersity, and high aspect ratios of the clay particles and the complexity of the aggregates, or dispersion medium. The measured clay agglomerates in suspension were found to be in the nanometer range in the more compatible solvents, and their sizes correlated with the Hansen solubility parameter space distance between the clay modifiers and the solvents. Mass detection limits for size determination were in the range from 1 to 9 mg/L. The methodology thus provides simple, rapid, and inexpensive characterization of clays or particles in the nano- or microsize range in low concentrations in various liquid media, including complex mixtures or highly viscous fluids that are difficult to analyze with DLS. In addition, by combining UV-VIS spectroscopy with DLS it was possible to discern flocculation behavior in liquids, which otherwise could result in false size measurements by DLS alone.
Container grown woody ornamentals were irrigated with four different treatments based on daily wa... more Container grown woody ornamentals were irrigated with four different treatments based on daily water use (DWU) to study the impact on plant growth, leachate electrical conductivity and pH, and runoff water volume and nutrient content. A completely randomized design was used with 4 overhead irrigation treatments: 1) irrigation scheduled to replace 100% DWU per application (100DWU); 2) irrigation alternating every other application with 100% replacement of DWU and 75% DWU the following application (100-75); 3) irrigation scheduled on a three-application cycle replacing 100% DWU followed by two applications replacing 75% DWU (100-75-75); 4) irrigation scheduled on a four-application cycle replacing 100% DWU followed by three applications replacing 75% DWU (100-75-75-75). The substrate volumetric moisture content (SVMC) was determined by soil moisture sensors (Model 10 HS, Decagon Devices, Inc., Pullman, WA 99163) placed in a subset of containers. Plant DWU was calculated as the differe...
The wear behaviors of five different zinc-aluminum (ZA)-based alloys containing silicon, copper, ... more The wear behaviors of five different zinc-aluminum (ZA)-based alloys containing silicon, copper, and 8 and 16 pct on volume of reinforcing silicon carbide (SiC) particles were analyzed. Hardness, dimensional stability, and wear tests were performed on these five alloy samples. Microstructural investigation and semiquantitative chemical analysis of the different alloying characteristics of the cast samples, the wear surface, and the
International Journal of Biological Macromolecules, 2013
The characterization and antimicrobial properties of water chestnut starch-chitosan (WSC) films c... more The characterization and antimicrobial properties of water chestnut starch-chitosan (WSC) films containing Cornus officinalis fruit extract (COE 1% w/w), glycerol monolaurate (GML 1% w/w), nisin (10,000 IU/g), pine needle essential oil (PNEO 0.35% v/v), and their combinations were evaluated. Incorporation of COE decreased pH value of the film-forming solution, the moisture content and the water absorption expansion ability (WAEA). GML-incorporated film had lower WAEA, tensile strength, elongation and puncture strength. However, films with nisin displayed good mechanical properties. All the treated films were less transparent and higher in water vapour permeability values. For film microstructure, the presence of PNEO caused discontinuities with lipid droplets or holes embedded in a continuous network and the incorporation of GML led to abaisse-like structures. The COE, GML, nisin, PNEO and their combinations incorporated in the WSC films are effective in inhibiting the growth of Escherichia coli O157:H7, Staphylococcus aureus and Listeria monocytogenes at different levels. The results showed that WSC films containing COE and GML, GML and nisin, COE and nisin were able to reduce the number of E. coli O157:H7, S. aureus and L. monocytogenes. This research has potential applications to the extension of the shelf life of food products.
Abstract The properties of sheet containing mechanically recycled postconsumer poly (L-lactic aci... more Abstract The properties of sheet containing mechanically recycled postconsumer poly (L-lactic acid) bottle flakes blended with virgin poly (L-lactic acid) resin were assessed. Poly (L-lactic acid) bottles were flaked, cleaned, blended with virgin resin and then extruded and ...
U.S. consumers are the largest contributors to food waste generation (FWG), but few models have e... more U.S. consumers are the largest contributors to food waste generation (FWG), but few models have explained how households waste food. This study examines how discrete-event simulation (DES) can identify areas for reducing FWG through packaging and consumer milk consumption behavioral changes. Household model parameters included: amount and type of consumption, type and number of containers bought, buying behavior, and shelf life of milk. Simulations comparing the purchase of quart, half gallon, and gallon milk containers were run for 10,000 days to identify which package type reduced waste for 50 1, 2 and 4-person households. Based on consumption averages from the U.S. National Dairy Council, results suggest that if 1 and 4-person households change their purchasing behavior from 1 half-gallon to 1 quart and 2 gallons to 3 half-gallons, they can reduce their greenhouse gas (GHG) emissions from milk consumption by 33% and 12%, respectively, without reducing their total milk consumption...
The research on a self-decontaminating surface has received significant attention because of the ... more The research on a self-decontaminating surface has received significant attention because of the growth of pathogenic microorganisms on surfaces. In this study, a novel and simple technique for producing an active surface with antimicrobial functionality is demonstrated. A tethering platform was developed by grafting the biocide ampicillin (Amp) to a nanoclay and dispersing the nanoclay in a UV-curable acrylate coating applied on polypropylene films as the substrate. A coupling agent, [3-(glycidyloxy)propyl]trimethoxysilane, was used as a linker between the nanoclay and Amp. The Amp-functionalized clay was further modified with an organic surfactant to improve the compatibility with the coating. Several characterization assays, such as Fourier infrared transform analysis, thermogravimetric analysis, and X-ray diffraction, were conducted to confirm the presence of Amp in the nanoclay. Transmission electron microscopy images revealed that the clay particles were well dispersed in the coating and had a partial exfoliated morphology. The active coating surface was effective in inhibiting the growth of Gram-positive Listeria monocytogenes and Gram-negative Salmonella Typhimurium via contact. These findings suggest the potential for the development of active surfaces with the implementation of nanotechnology to achieve diverse functionalities.
Container-grown woody ornamentals were irrigated with 4 treatments based on daily water use (DWU)... more Container-grown woody ornamentals were irrigated with 4 treatments based on daily water use (DWU) to study the impact of irrigation regime on plant growth, leachate electrical conductivity and pH, and runoff water volume and nutrient content. Hibiscus syriacus ‘Bricotts’, Euonymus alatus ‘Select’, Weigela florida ‘Alexandra’, and Spiraea japonica ‘Yan’ were grown in 10.2-L (#3) containers and subject to four overhead irrigation treatments: 1) irrigation scheduled to replace 100% DWU per application (100DWU); 2) irrigation alternating every other application with 100% replacement of DWU and 75% DWU the following application (100-75); 3) irrigation scheduled on a three-application cycle replacing 100% DWU followed by two applications replacing 75% DWU (100-75-75); and 4) irrigation scheduled on a four-application cycle replacing 100% DWU followed by three application replacing 75% DWU (100-75-75-75). Container substrate consisted of 85% pine bark: 15% peatmoss (vol: vol). Plants were ...
Containers made from natural fiber and recycled plastic are marketed as sustainable substitutes f... more Containers made from natural fiber and recycled plastic are marketed as sustainable substitutes for traditional plastic containers in the nursery industry. However, growers' acceptance of alternative containers is limited by the lack of information on how alternative containers impact plant growth and water use (WU). We conducted experiments in Michigan, Kentucky, Tennessee, Mississippi, and Texas to test plant growth and WU in five different alternative containers under nursery condition. In 2011, 'Roemertwo' wintercreeper (Euonymus fortunei) were planted in three types of #1 (%1 gal) containers 1) black plastic (plastic), 2) wood pulp (WP), and 3) recycled paper (KF). In 2012, 'Green Velvet' boxwood (Buxus sempervirens · B. microphylla siebold var. koreana) was evaluated in 1) plastic, 2) WP, 3) fabric (FB), and 4) keratin (KT). In 2013, 'Dark Knight' bluebeard (Caryopteris ·clandonensis) was evaluated in 1) plastic, 2) WP, and 3) coir fiber (Coir). Pla...
Ultraviolet-visible (UV-Vis) spectroscopy methodology was developed and utilized for the in situ ... more Ultraviolet-visible (UV-Vis) spectroscopy methodology was developed and utilized for the in situ nanoscale measurement of the size of mineral clay agglomerates in various liquid suspensions. The clays studied were organomodified and unmodified montmorillonite clays (I.44p, Cloisite 93a, and PGN). The methodology was compared and validated against dynamic light scattering (DLS) analysis. The method was able to measure clay agglomerates in solvents in situations where DLS analysis was unsuccessful due to the shapes, polydispersity, and high aspect ratios of the clay particles and the complexity of the aggregates, or dispersion medium. The measured clay agglomerates in suspension were found to be in the nanometer range in the more compatible solvents, and their sizes correlated with the Hansen solubility parameter space distance between the clay modifiers and the solvents. Mass detection limits for size determination were in the range from 1 to 9 mg/L. The methodology thus provides simple, rapid, and inexpensive characterization of clays or particles in the nano- or microsize range in low concentrations in various liquid media, including complex mixtures or highly viscous fluids that are difficult to analyze with DLS. In addition, by combining UV-VIS spectroscopy with DLS it was possible to discern flocculation behavior in liquids, which otherwise could result in false size measurements by DLS alone.
Container grown woody ornamentals were irrigated with four different treatments based on daily wa... more Container grown woody ornamentals were irrigated with four different treatments based on daily water use (DWU) to study the impact on plant growth, leachate electrical conductivity and pH, and runoff water volume and nutrient content. A completely randomized design was used with 4 overhead irrigation treatments: 1) irrigation scheduled to replace 100% DWU per application (100DWU); 2) irrigation alternating every other application with 100% replacement of DWU and 75% DWU the following application (100-75); 3) irrigation scheduled on a three-application cycle replacing 100% DWU followed by two applications replacing 75% DWU (100-75-75); 4) irrigation scheduled on a four-application cycle replacing 100% DWU followed by three applications replacing 75% DWU (100-75-75-75). The substrate volumetric moisture content (SVMC) was determined by soil moisture sensors (Model 10 HS, Decagon Devices, Inc., Pullman, WA 99163) placed in a subset of containers. Plant DWU was calculated as the differe...
The wear behaviors of five different zinc-aluminum (ZA)-based alloys containing silicon, copper, ... more The wear behaviors of five different zinc-aluminum (ZA)-based alloys containing silicon, copper, and 8 and 16 pct on volume of reinforcing silicon carbide (SiC) particles were analyzed. Hardness, dimensional stability, and wear tests were performed on these five alloy samples. Microstructural investigation and semiquantitative chemical analysis of the different alloying characteristics of the cast samples, the wear surface, and the
International Journal of Biological Macromolecules, 2013
The characterization and antimicrobial properties of water chestnut starch-chitosan (WSC) films c... more The characterization and antimicrobial properties of water chestnut starch-chitosan (WSC) films containing Cornus officinalis fruit extract (COE 1% w/w), glycerol monolaurate (GML 1% w/w), nisin (10,000 IU/g), pine needle essential oil (PNEO 0.35% v/v), and their combinations were evaluated. Incorporation of COE decreased pH value of the film-forming solution, the moisture content and the water absorption expansion ability (WAEA). GML-incorporated film had lower WAEA, tensile strength, elongation and puncture strength. However, films with nisin displayed good mechanical properties. All the treated films were less transparent and higher in water vapour permeability values. For film microstructure, the presence of PNEO caused discontinuities with lipid droplets or holes embedded in a continuous network and the incorporation of GML led to abaisse-like structures. The COE, GML, nisin, PNEO and their combinations incorporated in the WSC films are effective in inhibiting the growth of Escherichia coli O157:H7, Staphylococcus aureus and Listeria monocytogenes at different levels. The results showed that WSC films containing COE and GML, GML and nisin, COE and nisin were able to reduce the number of E. coli O157:H7, S. aureus and L. monocytogenes. This research has potential applications to the extension of the shelf life of food products.
Abstract The properties of sheet containing mechanically recycled postconsumer poly (L-lactic aci... more Abstract The properties of sheet containing mechanically recycled postconsumer poly (L-lactic acid) bottle flakes blended with virgin poly (L-lactic acid) resin were assessed. Poly (L-lactic acid) bottles were flaked, cleaned, blended with virgin resin and then extruded and ...
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