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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.
1

The structure of liquid ammonium chloride as determined by x-ray diffraction

Harris, Robert Laurence, January 1950 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1950. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
2

Influence of varying levels of ammonium chloride on urine pH and specific gravity, overall feed conversion, and water consumption in mature wether goats.

Kennedy, Matthew joseph 15 May 2009 (has links)
The objective of this study was to evaluate the effect of orally administered ammonium chloride (NH4CL) on pH and specific gravity of urine, overall gain, and water consumption in mature wethers on a grower/finisher ration. Obstructive urolithiasis, or urinary calculi, is a common problem in sheep and goat production systems utilizing a high grain diet, particularly one high in magnesium. Maintaining animals on a 70 to 90% concentrate ration is most conducive to the formation of urinary calculi. Boer cross wethers (n = 24) were stratified by body weight and randomly assigned within strata to one of three treatment groups. Wethers were placed on a common diet containing 2% NH4Cl during the three week collection period. Treatment consisted of daily oral dosages of 0g NH4CL (CON), 5.85 g NH4CL (TRT 1), or 13.8g NH4CL (TRT 2). Urine collected from TRT2 tested more acidic on the second and fourth collections before coming back linear constant with both the control (CON) and TRT1 . There was no effect of treatment (P < 0.001) on specific gravity of urine. Weight gain was greater (P < 0.01) in TRT1 (4.15 kg) and TRT2 (4.48 kg) as compared to CON wethers (2.95 kg). Water consumption was the most variable of all investigated objectives; all groups began with a linear increase for the first 4 d. Treatment 2 (P < 0.001) then showed significant increase at collections 2 and 4. Treatment 1 stayed more linear with the control with minimal increases (P < 0.001) occurring at periods of more acidic urine. This study indicates that administration of NA4Cl had minimal effect on urine pH, water consumption, and overall gain, but no effect on specific gravity.
3

The Effect of Continuous and Pulse Dose Ammonium Chloride Regimens on the Urine pH of Goats

Sprake, Philippa May 2012 August 1900 (has links)
Ammonium chloride (NH4Cl) has been the primary preventive modality for struvite urolithiasis in goats. This study investigated the effect of continuous and pulse dose NH4Cl therapeutic regimens on urine pH in ten goats. The initial regimen (feed additive) consisted of 0.007% NH4Cl as a feed additive. Following this week long regime, the two treatment regimens were designed as a standard ten goat cross-over design. The first treatment regimen (continuous) consisted of daily administration of a titrated dosage of NH4Cl for ten days, followed by four days without treatment. The third treatment regimen (pulse) used daily administration of a titrated dose of NH4Cl for three consecutive days followed by four days without treatment for three treatment periods. Ammonium chloride dosages were titrated to result in a urine pH of < 6.5 (target level) prior to commencing treatment regimens. Urine pH was evaluated once daily during feed additive regimen and twice daily during the treatment regimens. A Bayesian methodology was used to determine the daily odds ratios for production of target urine pH during treatment regimens. The odds ratios were also calculated between pulse dosages during the pulse regimen. The feed additive regimen did not result in target urine pH within 7 days. Treatment with the continuous regimen resulted in target pH, however, pH returned to >6.5 within five days, (odds ratio 0.23-1.56 at Treatment Time 10). The odds ratios for each pulse period of the pulse dose regimen were 2.20-7.45, 0.41-1.68 and 1.59-5.62 respectively. The results of this study indicate that variability in response to therapy warrants titrating individual dosages of NH4Cl, continuous therapy results in a loss of effectiveness, and pulse dosage is effective in repeatedly producing a urine pH of <6.5.
4

An analytical method for the determination of a dialkyl dimethyl quaternary ammonium chloride in beef liver tissue

Schmidt, Robert Charles January 2011 (has links)
Digitized by Kansas Correctional Industries
5

Synthesis and characterisation of polyelectrolytes based on polymers of diallyldimethyl ammonium chloride and poly(styrene-co-butadiene)

Svensson, David January 2012 (has links)
In printed electronics there are many polyelectrolytes to choose from. While polyelectrolytes such as polystyrene sulfonic acid can fulfill many ofthe desired functionalities of a semiconductor, there is a need for other polyelectrolytes with other functionalities, such as functionality at low airhumidity and better cross-linking possibilities, while still functioning as a good semiconductor.Within this thesis, there is a description of general polyelectrolytes, as well as various usages.The synthesis and characterization of new polyelectrolytes that have been developed, based upon diallyldimethyl ammonium chloride (DADMAC)and a derivative of polystyrene sulfonic acid (PSSH) is described.The study and experimental testing of the polymers as polyelectrolytes under different conditions is described.
6

Novel biocidal formulation

Wills, Peter January 2013 (has links)
In this modern age, society has become much more aware of the danger bacteria can have on people's health. Personal and household antimicrobial formulations are commonly used within the home to lower the levels of harmful bacteria such as E. Coli, Salmonella and Pseudomonas. The active which kills the bacteria within the formulation is described as a biocide. This research looks at the often neglected potential of cationic polyelectrolyte as a biocide, firstly within solution and secondly in creating an antimicrobial surface. The solution properties and antimicrobial activity for a range of commercially available cationic polyelectrolytes (polymeric quaternary ammonium compounds (QAC) and biguanides) of differing molecular weights were investigated. All polyelectrolytes were observed to have some level of antimicrobial activity. The second phase of this research investigated polyelectrolyte/surfactant/water mixture of similar charge (cationic). Two QAC surfactants were investigated: Alkyl (C12 70%; C14 30%) dimethyl benzyl ammonium chloride (BAC) and Didecyldimethylammonium chloride (DDQ). At a critical concentration, these mixtures segregatively phase separate into a surfactant rich upper phase and polyelectrolyte rich lower phase. This phase separation phenomenon was investigated in respect of surfactant and polyelectrolyte type as well as polyelectrolyte molecular weight. Surfactant type was observed to be the dominant factor in determining the onset of phase separation and by mixing different ratios of surfactants the ability to tune this phase separation concentration was shown. Dilute solutions of these mixtures well below their respective phase separation concentration were then deposited onto glass substrates via a drop cast or inkjet printer method. The surfactant/polyelectrolyte film composites left after drop evaporation ranged from an amorphous film to nodular like structures. The ability to order/structure actives onto a surface could alter active adhesion and surface roughness properties of the film. This change in surface property could consequently affect antimicrobial performance.
7

Fate and effect of alkyl benzyl dimethyl ammonium chloride in mixed aerobic and nitrifying cultures

Yang, Jeongwoo 27 August 2007 (has links)
Quaternary ammonium compounds (QACs) are widely used in commercial and consumer applications as disinfectants, fabric softeners, hair conditioners, and emulsifying agents. The massive production and utilization of QACs has led to their extensive discharge into the environment, raising concerns globally. Several studies have reported on potential risks and detrimental effects of QACs on the natural environment and public wastewater treatment plants. Biological treatment has been found to be an effective way to remove QACs and especially aerobic treatment processes can provide rapid biodegradation via a consortium of bacteria. Although extensive research has been conducted on the fate and effect of QACs, relatively little is known about their effect on aerobic biological treatment processes, especially on nitrification. Research was conducted on the fate and effect of alkyl benzyl dimethyl ammonium chloride (AB), a QAC widely used as disinfectant, in mixed aerobic and nitrifying cultures. The results of this study demonstrated that up to 50 mg/L AB was efficiently degraded in a mixed aerobic culture fed with dextrin and peptone, although trace residual AB levels were observed. Nitrification of the produced ammonia was complete at an AB concentration of 20 mg/L after an acclimation period, but was almost completely inhibited at 50 mg/L. Mixed aerobic cultures maintained only with AB as external nitrogen and carbon source achieved a high degree of AB degradation at both 20 and 50 mg/L. Ammonia oxidation by a nitrifying culture, enriched with ammonium chloride and sodium bicarbonate, was inhibited with increasing AB concentration and completely ceased at 15 mg/L AB. Degradation or utilization of AB was not observed for all tested AB concentrations between 2 to 20 mg/L. Based on these experimental results, and assuming non-competitive inhibition, a relatively low value of the AB inhibition coefficient was obtained, which indicates a relatively high susceptibility of the ammonia oxidizers to AB. The results of this study have significant implications for both engineered and natural systems relative to the fate and effect of QACs.
8

NÃveis de cloro para codornas japonesas (Coturnix coturnix japonica) nas fases de crescimento e produÃÃo / Chlorine levels for Japanese quails (Coturnix coturnix japonica) during the growing and production

Roseane Madeira Bezerra 05 February 2010 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Com o objetivo de avaliar os efeitos dos nÃveis de cloro da raÃÃo nas fases de crescimento e produÃÃo de codornas japonesas foram realizados dois experimentos, nos quais, foram avaliados os nÃveis de 0,07; 0,12; 0,17; 0,22; 0,27 e 0,32% de cloro. No primeiro experimento (fase de crescimento), 384 codornas com um dia de idade distribuÃdas em um delineamento inteiramente casualizado, com seis tratamentos de oito repetiÃÃes de oito aves cada. Conforme os resultados, no perÃodo de 1 a 42 dias, com o acrÃscimo do nÃvel de cloro na raÃÃo houve aumento linear no consumo de raÃÃo (g/ave) e no ganho de peso (g/ave) e reduÃÃo linear na relaÃÃo consumo de Ãgua/consumo de raÃÃo e na umidade das excretas. Entretanto, a conversÃo alimentar (g/g), a ingestÃo de Ãgua (ml/ave/dia), os coeficientes de digestibilidade da matÃria seca (CDMS), do nitrogÃnio (CDN) e da energia bruta (CDEB) e os valores de energia metabolizÃvel aparente (EMA) e aparente corrigida para nitrogÃnio (EMAn) das raÃÃes nÃo foram influenciados pelo nÃvel de cloro Ainda nesse ensaio, observou-se que os nÃveis de cloro recebido pelas codornas na fase de crescimento nÃo afetaram significativamente o desempenho da fase de postura. No segundo experimento, 288 codornas com dezessete semanas de idade foram distribuÃdas em um delineamento inteiramente casualizado, com seis tratamentos, oito repetiÃÃes e seis aves por unidade experimental. Os nÃveis de cloro nÃo influenciaram significativamente o consumo de raÃÃo (g/ave/dia), o consumo de Ãgua (ml/ave/dia), a percentagem de postura (%), o peso do ovo (g), a massa de ovo (g/ave/dia), a conversÃo alimentar (g/g), a umidade das excretas, os coeficientes de digestibilidade da matÃria seca (CDMS), nitrogÃnio (CDN) e energia bruta (CDEB), os valores de energia metabolizÃvel aparente (EMA) e aparente corrigida (EMAn), as Unidades Haugh, as percentagens de albÃmen, gema e casca. Entretanto, a gravidade especÃfica aumentou linearmente com o acrÃscimo de cloro na raÃÃo. Considerando os resultados, podese recomendar que as raÃÃes para codornas japonesas na fase de crescimento (1 a 42 dias) e de produÃÃo formuladas com milho e farelo de soja podem conter nÃveis de cloro de atà 0,32% sem prejuÃzo para os parÃmetros de desempenho e qualidade dos ovos. / In order to evaluate the effects of chlorine levels in the diet of growing and production of Japanese quails were conducted two experiments in which we assessed the levels of 0.07, 0.12, 0.17, 0.22, 0.27 and 0.32% chlorine. In the first experiment (growing phase), 384 quail on a day-old distributed in a completely randomized design with six treatments of eight replicates of eight birds each. According to the results for the period from 1 to 42 days, with the addition of chlorine level in the diet linearly increased feed intake (g/bird) and weight gain (g/bird) and a linear decrease in the ratio of consumption water/feed intake and excreta moisture. However, feed conversion (g/g), water intake (ml/bird/day), the digestibility of dry matter (CDMS), nitrogen (CDN) and gross energy (GEDC) and the values of metabolizable energy (AME) and apparent nitrogen corrected (AME) of feed were not affected by the level of chlorine still in testing, we found that chlorine levels received by the quails in the growing phase did not significantly affect the performance of phase posture. In the second experiment, 288 quail with seventeen weeks of age were distributed in a completely randomized design with six treatments, eight replicates and six birds per experimental unit. Chlorine levels did not significantly influence feed intake (g/bird/day), water consumption (ml/bird/day), the percentage of stance (%), egg weight (g), the mass of egg (g/bird/day), feed conversion (g/g), the moisture of excreta, the digestibility of dry matter (CDMS), nitrogen (CDN) and gross energy (GEDC), the metabolizable energy apparent (AME) and corrected apparent (AME), Haugh Units, the percentages of albumen, yolk and shell. However, the specific gravity increased linearly with the addition of chlorine in the feed. Considering the results, we can recommend diets for Japanese quails in the growing phase (1 to 42 days) and production made with corn and soybean meal can contain chlorine levels up to 0.32% subject to the parameters performance and egg quality
9

Optimisation of water-in-oil microemulsion formulation stabilised by nonylphenol ethoxylated phosphate ester

Mdhlovu, Johan 06 March 2006 (has links)
Water-in-oil (w/o) microemulsion systems, stabilised by either an anionic surfactant or a cationic surfactant were studied. The anionic system consisted of ethoxylated nonylphenol phosphate esters (Atpol), Shellsol oil and an alcohol. These microemulsions tolerated an increase in ionic strength of the water phase up to a point: Beyond this point no microemulsion could be obtained. However, adding amine salts, e.g. diethanolamine nitrite, improved the emulsification of the aqueous phase. Increasing the alcohol (cosurfactant) chain length up to octanol also increased the uptake of the aqueous phase. Thus octanol yielded the best results in terms of emulsifying large volumes of the water-phase, particularly at high salt concentrations. A key objective was to prepare stable microemulsions with high nitrite content. The maximum microemulsion nitrite contents (expressed as NaNO2equivalent by mass) achieved were: -- About 10% when a 30% NaNO2solution was emulsified -- 23% when neat diethyl ethanolamine nitrite (DEEAN) was solubilized, and -- 23% for mixtures of diethanolamine nitrite (DEtOHAN) and NaNO2 in water. The cationic microemulsion system was based on the double-chain cationic surfactant, didodecyldimethyl ammonium chloride (DDAC). In this case the solubilization of the following acetate salts were investigated: ammonium, sodium, magnesium, zinc and manganese. As with the Atpol system, it was found that increasing the ionic strength is detrimental to microemulsification of the aqueous phase. In the DDAC system, an increase in the alcohol chain length beyond butanol led to reduced aqueous phase uptake. Thus the natures and concentrations of the surfactant and the cosurfactant as well as the ionic strength of the aqueous phase determine the stability and the emulsification of large volumes of aqueous phase. In general there is an optimum ionic strength at which the salt content of the microemulsion formulation is maximised. / Dissertation (MSc (Chemistry))--University of Pretoria, 2007. / Chemistry / unrestricted
10

Enhancing the Residual Efficacy of Wood Phytosanitation using a Silane

Johnson, Todd Ellis 12 May 2012 (has links)
This study investigates use of the organosilane 3-(trimethoxysilyl) propyldimethyl octadecyl ammonium chloride (Si-Quat) as a wood treatment to impart residual moisture and organism control on wood substrates. Study 1, which utilized experimental testing procedures to evaluate mold growth after standardized heat treatment, indicated less surface mold on treated samples. Study 2, which utilized standardized testing procedures to evaluate Si-Quat treated wood’s resistance to subterranean termite attack, indicated greater termite mortality and less feeding on treated wood, as well as increased termite feeding preference for untreated wood. Study 3, which utilized standardized testing procedures to evaluate water repellency, indicated significantly reduced moisture gain at higher silane-based treatment levels in comparison to untreated wood. It is concluded that a silane based treatment utilized in this study can be effective for organism control and the possible supplementation to current phytosanitation of wood packaging materials.

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