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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
511

A Comparison of Sweet Cream Buttermilk Powder with Nonfat Dried Milk Solids in the Manufacture of Ice Cream

Yanasugondha, Davi 01 May 1951 (has links)
Properly dried sweet cream buttermilk, because of its high fat and lecithin contents, should make superior ice cream. Its use as a source of serum solids in ice cream. Its use as a source of serum solids in ice cream mix would open an outlet for this butter by-product and would serve the needs of ice cream manufacturers during nonfat dry milk solids shortage and it may make a higher score ice cream. The demand for milk solids shortage and it may make a higher score ice cream. The demand for milk solids has been increasing so rapidly that today the by-products of the dairy industry are being utilized as sources of human food to a much greater extent than before. In past years the greater bulk of creamery buttermilk has been utilized as animal feeds. Attempts are being made to convert more of this by-product into channels of human consumption. As the manufacture of sweet cream butter is increasing at a rapid pace, a larger supply of buttermilk product of high quality which is fit for human consumption is available in the market. Many previous investigators have used buttermilk products as a source of serum solids in ice cream mix with favorable results. The advantage claimed has been that it tends to improve the whipping ability of ice cream mixes and to impart richer flavor to the product. These beneficial qualities have been attributed to the butterfat and the phospholipids, of which lecithin is predominant. The work of Chapman and Supplee shows that buttermilk and cream contins several times as much licithin as skimmilk. The amounts of total phospholipids reported by Holm et al and Wright et al are approximately 1.77 per cent in dry buttermilk and 1.06 per cent in dry skim milk.
512

Regulated Deficit Irrigation of 'Montmorency' Tart Cherry

Papenfuss, Kylara A. 01 May 2010 (has links)
Regulated deficit irrigation (RDI) is the strategy of reducing irrigation rates during a specific period of growth and development, with the objective of conserving water and managing plant growth while maintaining or improving yield and fruit quality. Mature tart cherry (Prunus cerasus L. 'Montmorency') trees in a commercial orchard were subjected to a range of irrigation deficits from pit hardening to harvest during the 2007 and 2008 seasons. Irrigation treatments replaced from 62% to 96% of ETc, during that period. Midday stem water potential measurements were significantly different among treatments before harvest. However, fresh weight yield at harvest did not differ significantly among irrigation treatments in either year (P-value=0.64). In 2008 the amount of undersized fruit eliminated during packout was significantly higher in the treatments replacing 61% and 68% of ETc than in the control (P-value<0.0001), but only amounted to 2.0% and 1.4% of total yields, respectively. This small increase in undersized fruit did not significantly affect packout. Fruit quality measurements, such as soluble solids concentration and chroma of whole intact fruit, increased with the severity of the irrigation deficit. Visible surface bark damage from mechanical harvesting appeared less severe as deficit levels increased. Return bloom was not significantly affected by irrigation treatments.
513

Using Relevance Vector Machines Approach for Prediction of Total Suspended Solids and Turbidity to Sustain Water Quality and Wildlife in Mud Lake

Batt, Hussein Aly 01 May 2012 (has links)
Mud Lake is a wildlife refuge located in southeastern Idaho just north of Bear Lake that traps sediment from Bear River water flowing into Bear Lake.Very few water quality and sediment observations, if any, exist spatially in Mud Lake. Spatial patterns of sediment deposition may affect Mud Lake flows and habitat; prediction of those patterns should help refuge managers predict water quality constituents and spatial distribution of fine sediment.This will help sustain the purposes of Mud Lake as a habitat and migratory station for species. The main objective of the research is the development of Multivariate Relevant Vector Machine (MVRVM) to predict suspended fine sediment and water quality constituents, and to provide an understanding for the practical problem of determining the amount of data required for the MVRVM. MVRVM isa statistical learning algorithm that is based on Bayes theory.It has been widely used to predict patterns in hydrological systems and other fields. This research represents the first known attempt to use a MVRVM approach to predict transport of very fine sediment andwater quality constituents in a complex natural system. The results demonstrate the ability of the MVRVM to capture and predict the underlying patterns in data.Also careful construction of the experimental design for data collection can lead the Relevant Vectors (RVs is a subset of training observation which carries significant information that is used for prediction) to show locations of significant patterns. The predictions of water quality constituents will be of potential value to US Fish and Wildlife refuge managers in making decisions for operation and management in the case of Mud Lake based on their objectives, and will lead the way for scientists to expand the use of the MVRVM for modeling of suspended fine sediment and water quality in complex natural systems.
514

Estimating Total Phosphorus and Total Suspended Solids Loads from High Frequency Data

Jones, Amber Spackman 01 December 2008 (has links)
Frequently measured turbidity was examined as a surrogate for total phosphorus (TP) and total suspended solids (TSS) loads at two locations in the Little Bear River, Utah, USA. Using regression techniques, equations were developed for TP and TSS as functions of turbidity. The equations accounted for censored data, and additional explanatory variables to represent hydrological conditions were considered for inclusion in the equations. By using the resulting surrogate relationships with high frequency turbidity measurements, high frequency estimates of TP and TSS concentrations were calculated. To examine the effect of sampling frequency, reference loads were determined from the concentration records for two water years. The concentration records were artificially decimated to represent various frequencies of manual grab sampling from which annual loads were calculated and compared to the reference loads.
515

Use of Corn Syrup Solids of Different Dextrose Equivalents in the Manufacture of Frozen Desserts

Axelgard, Wiggo F. 01 May 1954 (has links)
Importance of problem: The ice cream industry continually faces the problem of improving its frozen desserts. At the present time corn syrup solids are being used to supplement milk serum solids to improve the body and texture of these products. One of the problems is to increase the total solids content of frozen desserts without increasing sweetness or developing sandiness in the finished product. There is a limit to the amount of milk serum solids that can be used because of the danger of sandiness and the cost . The use of corn syrup solids helps to overcome these limiting factors. The corn syrup solids product now used contains a dextrose equivalent of 42. The corn products manufacturers are beginning to make a product with different dextrose equivalents with different degrees of sweetness. Modifications of DE 42 contain dextrose equivalents of 24 and 31 and will add corn syrup solids of different dextrose equivalents or degrees of sweetness to these frozen desserts. Robert L. Lloyd defines dextrose equivalent as follows: The percentage of reducing sugars present on a dry basis indicates the degree to which conversion has been carried in the hydrolysis of starch. Dextrose has a DE of 100 and is used as the standard. The lower the dextrose equivalent of a product the less the sweetening power. Purpose of problem: 1. To determine the optimun amounts of corn syrup solids to use in building body and texture in frozen desserts without impairing flavor. 2. To determine the comparative value of different amounts of DE 31, DE 24, and DE42.
516

Effects of Soilless Substrate Systems and Environmental Conditions on Yield, Total Soluble Solids, and Titratable Acidity of Greenhouse Strawberry (Fragaria × ananassa)

McKean, Thomas January 2019 (has links)
No description available.
517

A Collisional Mechanism in the Ion-Solid Interaction Which Enhances Scattering Yields Near 180⁰

Holland, Orin Wayne 12 1900 (has links)
In the course of experiments using uniaxial double alignment channeling to investigate radiation damage in single crystals, an anomalously large ion-scattering yield from the near surface of disordered or simulated disordered solid targets was observed. The chronology of the discovery of this new ion-solid effect and its explanation are presented along with experiments detailing the dependence of the new effect upon ion type and energy, as well as target atomic number and density. Targets included a spectrum of polycrystalline elemental targets in a range Z = 29 to Z = 82. Also, the influence of the effect upon scattering yields from an aligned Au(110) single crystal is demonstrated.
518

Analysis of Aerial Multispectral Imagery to Assess Water Quality Parameters of Mississippi Water Bodies

Irvin, Shane Adison 11 August 2012 (has links)
The goal of this study was to demonstrate the application of aerial imagery as a tool in detecting water quality indicators in a three mile segment of Tibbee Creek in, Clay County, Mississippi. Water samples from 10 transects were collected per sampling date over two periods in 2010 and 2011. Temperature and dissolved oxygen (DO) were measured at each point, and water samples were tested for turbidity and total suspended solids (TSS). Relative reflectance was extracted from high resolution (0.5 meter) multispectral aerial images. A regression model was developed for turbidity and TSS as a function of values for specific sampling dates. The best model was used to predict turbidity and TSS using datasets outside the original model date. The development of an appropriate predictive model for water quality assessment based on the relative reflectance of aerial imagery is affected by the quality of imagery and time of sampling.
519

Bioflocculation of Wastewater Treatment Pond Suspended Solids

Lefebvre, Louis 01 December 2012 (has links) (PDF)
Bioflocculation of Wastewater Treatment Pond Suspended Solids Louis Lefebvre Wastewater treatment lagoons and high rate algae ponds (HRAPs) can provide cost effective wastewater treatment, but they commonly have high effluent concentrations of total suspended solids (TSS). In this thesis algae pond effluent was treated in a beaker testing apparatus (mixed and aerated) with various mixtures of activated sludge and primary effluent simulating differing activated sludge aeration basin compositions then was allowed to settle to assess settleability. Conventionally, microalgal suspended solids are removed by chemical coagulation followed by separation methods that often have a high cost relative to the low cost lagoon or HRAP system where the solids were produced. This separation step is often cost prohibitive or operationally complex for municipalities or too energy intensive for application in algae biofuels production. This research investigates using a small amount of activated sludge material to promote bioflocculation of algae in pond effluent. It was hoped that the findings may demonstrate a path for municipalities to keep their lagoons, while increasing capacity and improving treatment without excessive cost or complexity. Experiments were conducted on microalgae samples from a pilot-scale HRAP and activated sludge and primary effluent samples from a local municipal wastewater plant. The samples were placed in a mixing apparatus and allowed to settle for a given period of time, after which TSS was analyzed for settleability. The experiments investigated the effect of various lab-scale activated sludge reactor operational schemes by varying the volumes (and masses) of activated sludge, algae-rich water, and activated sludge in the beaker. Results in the sorption test (tests with only activated sludge and algae-rich water) demonstrated algae pond effluent treated with activated sludge concentrations of 3000 mg/L or greater produced final effluent TSS concentrations near discharge requirements (40-50 mg/L) with only 30 minutes of settling and without addition of primary effluent. However, such high activated sludge concentrations are not feasible at full scale. Furthermore, beakers with activated sludge concentrations greater than 3000 mg/L reduced TSS concentrations by more than 150 mg/L with only 30 minutes of settling and without addition of primary effluent. Results in the aerobic beaker tests (tests with primary effluent, activated sludge, and algae-rich water) showed greater than 200 mg/L TSS removal and final effluent TSS concentration less than 30 mg/L was achieved using activated sludge to primary effluent volumetric ratios of 1:1 and greater which corresponded to activated sludge concentrations of 730 mg/L and greater. Activated sludge concentrations of 730 mg/L may not be feasible at full scale. This report shows that a PETRO-like process is effective in lowering wastewater pond suspended solids, however not to typical discharge standards.
520

The Study Of Three Different Layered Structures As Model Systems For Hydrogen Storage Materials

Öztek, Muzaffer Tonguç 01 January 2011 (has links)
The strength and success of the hydrogen economy relies heavily on the storage of hydrogen. Storage systems in which hydrogen is sequestered in a solid material have been shown to be advantageous over storage of hydrogen as a liquid or compressed gas. Many different types of materials have been investigated, yet the desired capacity and uptake/release characteristics required for implementation have not been reached. In this work, porphyrin aggregates were investigated as a new type of material for hydrogen storage. The building blocks of the aggregates are porphyrin molecules that are planar and can assume a face to face arrangement that is also known as H-aggregation. The H-aggregates were formed in solution, upon mixing of aqueous solutions of two different porphyrins, one carrying positively charged and the other one carrying negatively charged functional groups. The cationic porphyrin used was meso-tetra(4- N,N,N-trimethylanilinium) porphine (TAP) and it was combined with four different anionic porphyrins, meso-tetra(4-sulfonatophenyl)porphine (TPPS), meso-tetra(4-carboxyphenyl) porphine (TCPP), Cu(II) meso-tetra(4-carboxyphenyl) porphine, and Fe(III) meso-tetra(4- carboxyphenyl) porphine. The force of attraction that held two oppositely charged porphyrin molecules together was electrostatic attraction between the peripheral groups. Solid state aggregates were successfully isolated either by solvent evaporation or by centrifuging and freeze drying. TCPP-TAP and Cu(II)TCPP-TAP aggregates were shown to interact with hydrogen starting from 150 °C up to 250 °C. The uptake capacity was about 1 weight %. Although this value is very low, this is the first observation of porphyrin aggregates absorbing hydrogen. This opened the way for further research to improve hydrogen absorption properties of these iv materials, as well as other materials based on this model. Two other materials that are also based on planar building blocks were selected to serve as a comparison to the porphyrin aggregates. The first of those materials was metal intercalated graphite compounds. In such compounds, a metal atom is placed between the layers of graphene that make up the graphite. Lithium, calcium and lanthanum were selected in this study. Theoretical hydrogen capacity was calculated for each material based on the hydriding of the metal atoms only. The fraction of that theoretical hydrogen capacity actually displayed by each material increased from La to Ca to Li containing graphite. The weight % hydrogen observed for these materials varied between 0.60 and 2.0 %. The other material tested for comparison was KxMnO2, a layered structure of MnO2 that contained the K atoms in between oxygen layers. The hydrogen capacity of the KxMnO2 samples was similar to the other materials tested in the study, slightly above 1 weight %. This work has shown that porphyrin aggregates, carbon based and manganese dioxide based materials are excellent model materials for hydrogen storage. All three materials absorb hydrogen. Porphyrin aggregates have the potential to exhibit adjustable hydrogen uptake and release temperatures owing to their structure that could interact with an external electric or magnetic field. In the layered materials, it is possible to alter interlayer spacing and the particular intercalates to potentially produce a material with an exceptionally large hydrogen capacity. As a result, these materials can have significant impact on the use of hydrogen as an energy carrier.

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