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The action of stannous chloride on ligninKinzer, Glenn Wilson January 1947 (has links)
This investigation was undertaken to further the work of Wagner who isolated coniferyl aldehyde by the treatment of wood with stannous chloride. An attempt has been made to determine whether or not coniferyl aldehyde can be obtained by the action of stannous chloride on two different lignin preparations, and thus answer the question as to whether Wagner’s coniferyl aldehyde came from the lignin of the wood or existed free in the wood.
1. It is unlikely that white pine lignin will yield coniferyl aldehyde when isolated and treated with stannous chloride according to the methods described in this investigation.
2. It is probable that Wagner’s coniferyl aldehyde existed free in the wood. / M.S.
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<i>Phlox paniculata</i> 'Blue Boy' and <i>Rudbeckia hirta</i> 'Indian Summer': Cultural Guidelines for Greenhouse Growth and Powdery Mildew ControlHill, Shannon 16 September 2004 (has links)
Little information is available about greenhouse production requirements of <i>Phlox paniculata</i> 'Blue Boy' and <i>Rudbeckia hirta</i> 'Indian Summer', both of which are extremely susceptible to powdery mildew. Some plant growth regulators (PGRs) have been reported to reduce severity of certain plant diseases. The objectives of these experiments were to: 1) define optimal fertilizer, irrigation rates, and media types for these cultivars; 2) determine optimal PGR rates for size control; and 3) determine effects of PGRs on powdery mildew severity on inoculated plants grown under optimal greenhouse conditons.
When looking at the variables height, average width, quality rating, and shoot dry weight, <i>Phlox paniculata</i> 'Blue Boy' grew best at 200 mg·L⁻¹ N in Fafard 3B medium and was not responsive to irrigation rate. Also, when looking at the same variables mentioned above, <i>Rudbeckia hirta</i> 'Indian Summer' grew best at 300 mg·L⁻¹ N in Scott's Sierra Perennial Mix at a high irrigation rate. The PGRs chlormequat chloride, daminozide/chlormequat chloride, and paclobutrazol were effective in controlling size of <i>Phlox</i>. During the first <i>Rudbeckia</i> experiment, paclobutrazol and uniconazole were effective in controlling plant size; in the second experiment daminozide, uniconazole and flurprimidol were effective.
In the fall experiment, 160 mg·L⁻¹ paclobutrazol was effective in reducing disease severity in Phlox; in the spring experiment, 4000 mg·L⁻¹ chlormequat chloride and 60 mg·L⁻¹ uniconazole were effective in reducing disease severity. In the <i>Rudbeckia</i> fall experiment, 160 mg·L⁻¹ of two forms of paclobutrazol were effective in reducing disease severity; in the spring experiment, only one of those forms (Bonzi) was effective. / Master of Science
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Solid-Solid Phase Transformation During the Reduction of Titanium Dioxide (Anatase) to Produce High-Grade Titanium PowderEphraim, Jeya, Patel, Rajnikant 11 March 2015 (has links)
No / Production of titanium is challenging and expensive due to the energy energy-intensive and time-consuming processes used at present. Current commercial production method reduces titanium tetrachloride with magnesium or sodium to produce titanium metal. Several researchers have attempted electro-deposition of titanium from ionic solutions but have faced difficulties in eliminating multivalent titanium ions and highly reactive dendrite products. In this paper, we report, for the first time, the solid-solid phase transformation of titanium dioxide with calcium metal, under suitable conditions, to form solid titanium metal powder (>98% pure) without any oxygen impurity. On phase characterisation, it was found that homogeneous alpha-titanium was produced. The paper also includes the results and interpretations obtained using quantitative analysis, X-ray diffraction (XRD), scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX) and phase diagram. The process is simple, green, rapid and cheap compared to the existing methods.
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Informovanost o nahrazení kuchyňské soli v potravinách / Knowledge of substitutes of salt in foodVaňková, Marie January 2016 (has links)
The diploma thesis deals with the issue of salt and possibility of its replacement in food. The chosen is topical because healthy nutrition is one of current modern trends. Table salt is an entire part of a diet of every person. As the compound of two biogenic elements - sodium and chlorine - it has unsubstitutable function in human body. However, an increased intake of sodium can be associated with health risks, especially hypertension. The World Health Organization recommends a maximum daily intake of salt 5 g. According to current statistics, nevertheless the salt intake in the Czech republic is up to three times higher. Therefore, it is appropriate to reduce the consumption of salt and attempt to its replacement without cutting down the taste of food. One of the goals of this thesis was find out possibilities of replacing the salt and what is their availability. The practical part deals with the results of survey, within these was examined the awareness of salt and the posibility of its replacement among different group of our population (students, pedagogical workers, heads of school canteens). In terms of established facts there was suggested a project called The salt is beneficial and dangerous which aids to raise awareness of students about this topic. These outputs can be put into the...
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Avaliação do método de extração eletroquímica de cloretos para reabilitação de estruturas de concreto com problemas de corrosão de armaduras. / Evaluation of the method of electrochemical extraction of chlorides ions for the rehabilitation of concrete structures with reinforcement corrosion problems.Monteiro, Eliana Cristina Barreto 11 October 2002 (has links)
O presente trabalho avalia o método de extração eletroquímica de íons cloreto na reabilitação de estruturas de concreto com problemas de corrosão de armaduras. Essa metodologia pode ser utilizada para evitar as desvantagens da recuperação tradicional do reparo localizado. No procedimento experimental foram realizados ensaios de laboratório em corpos-de-prova de forma prismática com dimensões reduzidas, moldados com diferentes relações água/cimento. A penetração de cloretos nos corpos-de-prova foi realizada de maneiras distintas: câmara de névoa salina e semiciclos de secagem e imersão parcial. Entre outros aspectos, foi avaliada a influência da espessura de cobrimento e da relação água/cimento na resposta do método através da determinação do teor inicial e final dos íons cloreto.Nas conclusões observa-se que a eficiência desse método foi até superior à encontrada em outros trabalhos da literatura. Nas séries cuja penetração de cloretos se deu através da câmara de névoa salina em média foram removidos 78% dos íons cloreto inicialmente presentes no concreto, nas séries onde a penetração de cloretos foi por semiciclos de secagem e imersão parcial obteve-se 91% de eficiência de remoção. / This present project evaluates the method of electrochemical extraction of chloride ions for the rehabilitation of concrete structures with reinforcement corrosion problems. This methodology can be used to prevent the disadvantages of traditional repair strategies in the patch repair. In the experimental procedure, tests performed in laboratory with specimens of prismatic form with reduced dimensions had been carried through, molded with different water/cement ratio. The chloride penetration in the specimens was carried through in distinct ways: salt spray chamber and semi cycles of drying and partial immersion. Among others aspects, the influence of the concrete cover and the water/cement ratio has been evaluated in the efficiency of method by determining the initial and the final chloride content. In the conclusions it is noticed that not only the test results did verify that this method successfully extracted chloride ions but it was much more efficient than previously reported in the literature. In the series where chloride penetration comes through the salt spray chamber, on average, this method removed 78% of the content of initial chloride ions in the concrete, in the series where the chloride penetration was done by semi cycles of drying and partial immersion, 91% of removal efficiency was obtained.
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Novel biocidal formulationWills, 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.
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Growth and Nutrition of Plants as Affected by Different Osmotic Concentrations of Calcium Chloride and Sodium Chloride in the SubstrateKhan, Mumtaz Ali 01 May 1956 (has links)
Considerable experimental evidence supports the concept that the growth of plants generally decreases progressively as the salt concentration of the substrate increases, but certain relationships between plant and substrate are still not fully understood. The chemistry of salt toxicity to plants involves many interactions both as to the quantity and kind of ions presented to the roots and those accumulated in the plants. Many plant species have shown sensitivity to excess accumulation of specific salts frequently encountered in saline soils. Thus Eaton (1942), Wadleigh, Hayward, and Ayers (1951 ) have shown most of the fruit trees to be susceptible to injury as a result of the accumulation of chloride ion. Wadleigh, et al. (1951) have reported orchard grass to be sensitive to calcium salts. Recently, Brown, Wadleigh, and Hayward (1953) have found calcium chloride more toxic to some fruit trees than isosmotic levels of sodium chloride. These and other studies have indicated a greater influence of specific ions than of the osnotic pressure of the solution.
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Evaporative drying of cupric-chloride droplets in a thermo-chemical cycle of hydrogen productionMarin, Gabriel 01 April 2008 (has links)
This thesis develops analytical and numerical solutions that predict behavior of Cupric-Chloride droplets undergoing spraying and drying processes. Cupric-Chloride (CuCl2) is present as molten salt and slurry within the Copper-Chlorine thermo-chemical cycle for generation of hydrogen. Utilizing low-grade heat from nuclear or industrial sources to assist drying of Cupric-Chloride can increase efficiency of the overall process. Analytical correlations for heat and mass transfer are developed and applied to the analysis of a solution of Cupric-Chloride, subject to various drying conditions. The study provides new information on effects of different concentrations of water in CuCl2 slurry drying at low air temperatures. / UOIT
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Environmental and Energy Saving Technologies of Vinyl Chloride ProductionKurta, Mykola 11 February 2013 (has links)
Recently, because of the increase of environmental concerns in process design, the need to enhance conversion to product and prevent generation of wasteful byproducts in the reactor network has become urgent. This prevents high cost treatment and separation costs downstream in the process. Therefore, in this thesis I focus on making production of vinyl chloride monomer (VCM) more efficient and on possible ways of industrial organochlorine waste (OCW) recycling. In particular, in the first experiment, we investigate how catalyst and its structure can affect product output.
Infrared spectroscopy and X-ray diffraction analysis were utilized to investigate the structure of the γ-Al2O3 carrier with CuCl2 catalyst on its surface. Structure of the two catalysts, HarshowX1 and MEDC-B, and their effect on the mechanism of ethylene oxidative chlorination reaction into 1,2-dichlorethane were studied. Differential thermal analysis and mass spectroscopy were applied to study the structure and the mechanism differences between the deposited and permeated CuCl2 catalysts.
The second experiment deals with ecological processing and recycling methods of wasteful byproduct that can be called chlororganic wastes. Typical waste products are 1,2-dichloroethane, 1,1,2-trichloroethane, vinylidene, and vinyl chloride monomer. Polymerization and copolymerization of typical waste products with their C5-C9 fraction resulted in non-toxic polymer products that can be used in construction and road-building industries. The possibility of joint chlorine and sulfide-containing chemical wastes recycling into polysulfide oligomeric products is discussed. This comprehensive recycling allows utilizing 80-90% of all wastes generated during synthesis of chlorinated products in the chemical industry.
The results of the studies aim to improve the conversion of ethylene to vinyl chloride and minimize the formation of byproducts.
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Chloride Ingress into Submerged Concrete Under Sustained LoadKaram, Andrew 24 January 2014 (has links)
A harsh, cold, and icy environment is of no surprise to the conditions of a winter climate, where the wide use of de-icing salts on roads and highways allows for the initiation of chloride-induced corrosion of the reinforcement of concrete structures; a reduced service life, loss of structural integrity, visible damages, and ultimately structural failure are among the many unwanted effects of rebar corrosion. Chloride ingress into concrete has been extensively studied for the last four decades; however, most of the relevant research to date does not take into account the effects of sustained loading on chloride transport properties. Therefore, the objectives of this study were to investigate the influence of sustained compressive and tensile stresses on chloride ingress into concrete, and ultimately to understand what the effect of sustained stress is on chloride penetration depth, on chloride concentration by % weight of concrete, and on apparent diffusion coefficients by comparing results to those of unloaded control specimens.
To achieve these objectives, six post-tensioned and four non-reinforced control concrete beams were constructed with different water-to-cement (w/c) ratios and completely submerged in a 4-5% de-icing salt (NaCl) solution for 12 weeks, allowing chloride transfer to be completely governed by continuous diffusion. The effects of supplementary cementing material on chloride ingress are also studied. Concrete beams were post-tensioned to induce variable sustained compressive and tensile stresses along the beam. After 12 weeks of exposure, beams were fractured at specific locations and sprayed with a 0.1N silver nitrate (AgNO3) solution to determine average penetration depths; chloride concentration profiles were obtained from potentiometric titration of grinded powder samples.
Apparent chloride diffusion coefficients were then obtained from the results of spraying AgNO3 and titration, the latter by non-linear regression curve-fitting to Fick’s second law of diffusion. A good agreement between results from both methods reveals that the use of AgNO3 in field is acceptable in predicting the rate of chloride ingress in concrete sustaining stress. The chloride diffusivity for each profile, relative to that of the unstressed section, was related to the compressive and tensile stresses in the concrete section. The experimental results indicate the dependence of chloride ingress and concentration on the type and level of sustained stress. An analysis of the results to study the effects of the w/c ratio using colourimetric (silver nitrate spray) and potentiometric titration methods was also completed.
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