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Author's abstract: Studies have shown that the use of peptide in the synthesis of some inorganic materials can help control their size, shape and structure. In this research, magnetic carbon nanotubes were synthesized using co-precipitation method in the presence of M6A-B1 peptide and characterizations such as; Scanning Electron Microscopy (SEM), Fourier Transform Infrared spectroscopy (FT-IR), X- ray Diffraction (XRD) and Thermogravimetric analysis (TGA) were carried out. Remediation studies were conducted with the aim of studying the effect of adsorbate concentration, pH and adsorbent concentration on the removal of TBO (Toluidiene Blue O) dye from an aqueous solution. Pseudo second order kinetics model was used in describing the rate of adsorption while the Langmuir isotherm model was used to study the interaction between the peptide functionalized material and the adsorbate. The separation factor, RL calculated for the studied dye concentrations showed that adsorption in the peptide functionalized material was favorable.

Author's abstract: Explicitly correlated coupled cluster singles, doubles, and perturbative triples level [CCSD(T)-F12] and second-order closed-shell Møllar-Plesset perturbative theory (MP2-F12) anharmonic vibrational frequencies are compared with gas phase experiment and higher-level computations. These involve CCSD(T) with the complete basis set limit extrapolation along with, an additive factor for the energy difference between core and noncore electrons and a similar additive difference for scalar relativity to give the CcCR approach. One hundred and sixty-nine vibrational frequencies are computed using CCSD(T)-F12 with the aug-cc-pVTZ basis set. For MP2-F12 twenty-five molecules are examined under aug-cc-pVDZ basis set. The CCSD(T) computational analysis of the closed-shell molecules' anharmonic vibrational frequencies resulted in a mean absolute error of 7.5 cm-1 between the CCSD(T)-F12 and CcCR. Comparison of the CCSD(T)-F12 with gas phase experiment gave mean absolute error of 5.8 cm-1 for twenty-nine closed-shell vibrational frequencies. However, the total computational time is reduced by more than 4 orders of magnitude when utilizing CCSD(T)-F12 as opposed to CcCR. From the computation, it is clear CCSD(T)-F12 correlated wave function is superior to MP2-F12, that this approach is a viable means of computing anharmonic vibrational frequencies of molecules when CcCR is not feasible to use.

Author's abstract: Metals are a large part of our daily lives, so studies must be carried out in order to improve the shelf life. Improving the lifetime of the metal is necessary due to the ever increasing uses as a natural resource. This has led to our research into corrosion inhibitors. Triazole heterocycles have been applicable in the world of science. Research into triazole-ion interaction has been carried out in the field of metal corrosion. The synthesized 1,2,3 triazole based core structures were studied for application in steel corrosion inhibition due to their ability to interact with ions. A mixture of 1M HCl and the triazole at increasing concentrations were tested in order to see the effect on resistivity. The impedance was tested on a potentiostat as the concentration was steadily increased. The resistivity of the solution shows there are interactions between the triazole compounds and the electron flow between electrodes. These interactions can be tested using Electrical Impedance Spectroscopy (EIS). The steel plates were submerged in the HCl mixed with different concentrations of the inhibitor in order to view differences in the surface area using Scanning Electron Microscopy (SEM). The Energy Dispersive Spectroscopy (EDS) analyzed the elemental composition of the steel in order to see the changes during the process. The study showed that the resistance to corrosion was greatest at the highest concentration that was tested (50 ppm). The surface area of the submerged steel was less corroded for the 50 ppm which suggests that corrosion slows down with a higher presence of the triazole inhibitor. Electrical Impedance Spectroscopy (EIS), Energy Dispersive Spectroscopy (EDS), Scanning Electron Microscopy (SEM) were used to characterize each triazole of interest.

Chirality (or handedness) is the property that a structure is "different" from its mirror image. Topology can be used to provide a rigorous framework for the notion of chirality. This project examines various types of chirality and discusses tools to detect chirality in graphs and knots. Notable theorems that are discussed in this work include ones that identify chirality using properties of link polynomials (HOMFLY polynomials), rigid vertex graphs, and knot linking numbers. Various other issues of chirality are explored, and some specially unique structures are discussed. This paper is borne out of reading Dr. Erica Flapan's book, When Topology Meets Chemistry. It follows the structure of the book closely, and in a sense, tells the same story, but as a modern adaptation. Every uncited theorem and definition and fact is from this book. The second part of this work focuses on using graph theory to better span molecular graphs. This part is significantly less explored, but nevertheless, presents some interesting prospects.

For the first time in Africa, studies investigating the polycyclic aromatic hydrocarbons (PAHs) levels in lichens (species Parmotrema austrosinense (Zalhbr.) Hale) was performed successfully using various sample preparation techniques. Sampling campaigns were conducted at 5 different sites across South Africa. Different sample preparation techniques were explored, and it was found that a quick, easy, cheap, effective, rugged and safe (QuEChERS) technique using n-Ư- hexane:acetone (1:1, v/v), never before applied to lichens, provided the best recoveries of internal standards (deuterated phenanthrene and pyrene), the highest total peak area for all PAHs of interest and relative standard deviations (%RSDs) comparable with the other preparation techniques explored (ultrasound assisted extraction, Soxhlet and microwave assisted extraction). Statistical analysis confirmed that QuEChERS performed significantly better than the other sample preparation techniques. The optimized sample preparation technique met the study's requirements, since it was a fast method, with good recoveries, using less solvents and minimal energy. It was determined that the internal standard needs a prolonged equilibration time (12 hr) on the lichen matrix for optimal recoveries, a new finding. Matrix matched standards were prepared and strong matrix effects were found; both strong enhancement (for the lighter PAHs) and strong suppression (for the heavier PAHs) were observed. The use of matrix matched standards were found to be imperative for the accurate determination of PAH concentrations in the samples, described for the first time in this study, since the matrix effects were found to be PAH and lichen specific and are crucial for accurate quantitation. Varying chlorophyll contents of the extracts was observed using fluorescence spectroscopy, despite being prepared in an identical manner and being of the same lichen species. Therefore, the chlorophyll content needs to be given along with determined PAH concentrations in lichens, based on a dried weight basis to allow for comparison between studies. All the lichen samples contained naphthalene, acenaphthylene, acenaphthene, fluorene, phenanthrene and benzo[a]pyrene. It was seen that a full range of PAHs in terms of mass was extracted and identified, thus Parmotrema austrosinense (Zalhbr.) Hale was an appropriate choice of lichen species. The order of most impacted sites to least impacted was found to be Pretoria Industrial Area (total PAH concentration 1001 ng.g-Ư-1)> Daspoort 2 (737 ng.g-Ư-1)> Daspoort 3 (693 ng.g-Ư-1)> Bulk urban site (633 ng.g-Ư-1)> Cathedral Peak (547 ng.g-Ư-1)> Cape Point Nature Reserve 1 (525 ng.g-Ư-1)> Cape Point Nature Reserve 2 (514 ng.g-Ư-1)> Cape Point Nature Reserve 3 (425 ng.g-Ư-1). The PAH profiles and PAH ring-Ư-size profile were used for source diagnostics and was seen to vary according to the types of pollution sources.

The biogeochemical cycles of both iodine and ozone are strongly linked to human health and global climate and are tightly coupled through chemical processes occurring in the surface ocean and troposphere. The concentration and distribution of these compounds have the potential to drive the oxidizing capacity and suite of chemical reactions occurring in the marine boundary layer. However, modeling coupled ocean-atmosphere systems involving them is challenging because of a limited understanding of the magnitude and dominant mechanisms controlling the fluxes of both species, in addition to temporally and spatially heterogeneous distributions of ozone and iodine in the sea surface and lower troposphere. Recent modeling studies have suggested a 30% contribution of halogen chemistry to overall oceanic ozone deposition, which is equivalent to an average annual cooling of 0.1 W m-2, or 30% of the warming effect of tropospheric ozone. This has the potential to appreciably alter the radiative balance of the atmosphere, with broad implications for global climate. A laboratory-based experimental approach was used to explore the role of organic microlayers at the air-water interface in mediating the sea-surface reaction between ozone and iodide. Films of stearic acid, an insoluble fatty acid, were shown to significantly reduce the rate of ozone deposition to both phosphate-buffered solutions and natural seawater. Taken in conjunction with the proportionality between iodide concentration and ozone deposition velocity, regional variability in the concentrations of iodide and insoluble organics have the potential to influence global fluxes of ozone and volatile iodinate compounds, and thus impact tropospheric chemistry and radiative forcing.

Recognition of structural features of DNA such as gaps, nicks and abasic sites is critical for many DNA-binding proteins, such as those involved in DNA damage repair. This study explores a novel strategy to model these protein-DNA interactions using phage display. Phage display has been commonly used to identity zinc fingers that bind to DNA sequences, but selection of peptides that binding to specific DNA structures has not been reported in the literature. A phage library of 109 variants was created based on one of three zinc finger domains of the DNA repair protein poly (ADP-ribose) polymerase I. The library, engineered at the DNA level using synthetic oligonucleotides and containing eight randomized codons in the "loop" region of the zinc finger, was cloned into a commercial T7 phagemid vector. Four rounds of selection against an immobilized nicked DNA target were carried out, the last of which resulted in 62% retention of phage. Sequencing of selected phage from this highly enriched library revealed convergence to a single 39-mer peptide, a truncated version of the designed 85-mer zinc finger. This peptide will be purified from transformed bacterial culture and its binding activity will be measured using fluorescence polarization. This project seeks to provide insight into the structure-function relationship of proteins that bind specific DNA structures and could possibly lead to a small peptide with diagnostic or therapeutic applications.

Polyoxometalates (POMs), which are inorganic metal oxide cluster anions with discrete structures, have been extensively studied in recent years due to their large variety of applications such as medicine, biology, catalysis, material sciences and chemical analysis. Ruthenium polypyridyl complexes have been extensively studied for their applications as photosensitizers in solar energy conversion and photoelectronic materials. Recently, ruthenium heterocyclic ligand complex-based building blocks have been used for the synthesis of hybrid organic-inorganic solids through the self-assembly. We are interested in the synthesis of ruthenium polypyridyl complexes and polyoxometalate anions through different ways such as coordination bonds, hydrogen bonds and ionic bonds to form hybrid organic-inorganic solids. Here, we report four novel hybrid organicinorganic compounds.

The first part of this manuscript deals with fundamental theories behind surface enhanced resonant Raman spectroscopy (SERRS). Optical absorption, resonant Raman and surface enhanced Raman spectra of chromophores bound to small isolated spherical gold or silver nanoparticles in colloidal solutions are collected, presented and SERRS excitation profiles are constructed. The goal of this project is to devise a chromophore-nanoparticle system such that chromophores bind to the nanoparticles but do not aggregate them. The spectra of such a system are analyzed to give clues about two enhancement mechanisms of SERRS-- a chemical enhancement mechanism and an electromagnetic one. In the second part of this manuscript, influences of metal nanoparticles on components of an organic polymer solar cell based on poly(3-hexylthiophene)/ (6,6)-phenyl-C61-butyric acid methyl ester active layer and poly(3,4-ethylenedioxy-thiophene):polystyrene-sulfonate supporting layer are studied. Different kinds of metal nanoparticles, such as silver and gold nanospheres, silver and gold nano-sputtered films, and silver nanoprisms, are incorporated in different geometries around the organic polymer layers and resulting extinction and surface enhanced Raman spectra are studied to give clues of possible solar efficiency enhancement mechanisms achieved by the nanoparticle incorporation.

The central premise of this thesis surrounds the effects of smoothing out the interface between core and shell of a nanoparticle system on the multi-exciton auger recombination kinetics as measured by transient absorption spectroscopy. Current research suggests smoothing out the interface between core and shell by alloying at high temperature reduces the auger rate [1], the rate at which multiexcitons combine down to a single exciton, and therefore increases the viability of the system for solar energy devices incorporating multiple exciton generation (MEG) technology. Auger recombination is so detrimental to these technologies because it occurs on a timescale of picoseconds, whereas radiative recombination, the primary mechanism for capturing energy in a nanoparticle and reemitting it, occurs on the nanosecond timescale. If multiexcitons were to be created in a nanocrystal sample with no means of controlling auger recombination, the auger mechanism would reduce these excitons down to one, and subsequent cooling of the hot carrier by phonon release would result in the loss of all of the extra energy that was stored in these excitons. In order to study this phenomenon multiple experimental techniques were performed on the nanoparticle samples, most notably UV-Vis, static fluorescence, Raman and transient absorption spectroscopies. As a result of this research, it is clear that alloying a core/shell particle has little effect on transient absorption kinetics, and that current theory on the subject needs to be reformulated. The experimental data contained herein is compared with calculations using a FORTRAN program developed by Professor David. F. Kelley, and confirms the process of alloying has little to no effect on auger rates of nanoparticles for this system. The calculations were also able to reproduce the UV-Vis and Raman spectra almost quantitatively if given the correct parameters, increasing confidence in the interpretation of the experimental results. This thesis does not aim to discuss what exactly controls the auger rate in nanoparticle systems, but a few conjectures based on sound observation and rooted in solid theory are presented.

Blood glucose homeostasis is tightly regulated in mammals. Insulin and exercise both stimulate glucose uptake into muscle cells via the GLUT4 transporter protein by independent pathways. Insulin triggers a tyrosine kinase pathway, but the mechanism stimulated by exercise is unknown. Discovering the mechanism may provide new therapeutic techniques for people with diabetes mellitus. While mammals have been studied extensively, research on a different model may elucidate aspects of this lesser known pathway. Reptiles rapidly deplete glycogen stores during bursts of activity and produce lactate as a byproduct of anaerobic metabolism. Lactate undergoes gluconeogenesis within muscle tissue, rather than liver tissue, to quickly replenish glycogen stores. Lactate is a preferred substrate for gluconeogenesis; thus, glucose uptake is inhibited. Since exercise has a significantly different effect on metabolism in reptiles, a reptilian model may provide novel information as to how exercise stimulates glucose uptake in mammals. Anolis sagrei were treated with combinations of exogenous insulin and exercise. Blood glucose, blood lactate, muscle glycogen, liver glycogen and muscle GLUT4 were measured. There was no significant treatment effect on levels of post-exercise blood glucose, however, levels of blood lactate increased significantly following exercise. Muscle glycogen was generally lower following exercise, though liver glycogen was not significantly different. GLUT4 was not detected. Finally, there was no difference in the level of any monitored metabolite following insulin injection. It appears that (1) gluconeogenesis occurs in muscle rather than liver tissue; (2) muscle contractions do not stimulate glucose uptake; (3) insulin may not affect glucose metabolism; (4) an isoform of the GLUT4 transporter protein may not exist. Future studies should compare the relative activities of effectors in reptiles and mammals following exercise to help elucidate the mechanism of the c.

Diepoxybutane (DEB), epichlorohydrin (ECH), and 1-(chloroethenyl)oxirane (COX) are small molecules that can form DNA interstrand cross-links. All three of these compounds are, or are metabolites of, industrial chemicals linked to cancer. Additionally, DEB is a metabolite of treosulfan, an anti-cancer drug. We are trying to determine why some of these compounds cause cancer and some can also cure cancer. To do so, we are attempting to link cytotoxicity, cross-linking efficiency, and apoptotic potential of the three compounds to see if any correlations exist. The purpose of this project was to quantify apoptotic potential of DEB, ECH and COX. This was done first by determining caspase activity. These studies showed that in terms of apoptotic potential, DEB>ECH>COX. Later studies quantified apoptosis using flow cytometry with Annexin V/propidium iodide staining. It was determined from these studies that DEB has the strongest apoptotic potential, and while it seems COX>ECH, more work must be done to be sure. If it is determined that DEB>COX>ECH, this would correlate directly to crosslinking efficiency as determined in other studies. Future work may use this correlation to mechanistically explain how some compounds cure cancer while others cause cancer.

This paper deals with two synthetic routes designed to yield carbon nucleosides. The C-nucleosides are compounds of potential antibiotic utility. The first approach, designed to yield 4-(2'-deoxyribofuranosyl )-1 ,2,3-triazole (1), consisted of silylation of methyl vinyl ketone (4) to give 2-trimethylsilylosy-l,3-butadiene (6), followed by a crossed aldol condensation with a heteroaromatic aldehyde to yield the aldol l. Epoxidation and cyclization of l was expected to yield the target molecule ~. The initial step, silylation of methyl vinyl ketone (4), was successful. Using model compounds the second step of the synthesis was attempted. Numerous attempts to condense (6) with 2-pyridinecarboxaldehyde (12) using a TiC1 4 catalyst proved to be unsuccessful with only unreacted 12 being recovered. The unreactivity of this system suggested a stable bidentate chelate between TiC1 4 and 2-pyridinecarboxaldehyde. Benzaldehyde (15) was used as a simpler model system. TiC1 4 promoted reaction between 15 and 6 resulted in a mixture of products, which proved very difficult to identify and separate. Fluoride ion was then exchanged for the TiC1 4 catalyst. Using phase transfer catalysts such as crown ethers and quartenary ammonium fluorides complex mixtures of reaction products were again obtained. Some of the isolated products indicated that 6 had undergone Diels-Alder reactions. The second approach towards synthesis of C-nucleosides involved elaboration of the heterocyclic unit from a protected sugar moiety . D-ribose was isopropyl ;dated to di-2,3,0-isopropylidene-D-ribofuranose (19). Tritylation of 19 yielded 2,3-di-0-isopropylidene-5-0-trityl-D-ribofuranose (20). The chloro sugar 2,3-di-0-isopropylidene-5-0-trityl-?-D-ribofuranosylchloride (21) was prepared from 20. We then planned to make the acid chloride of 21 which was expected to react with an aziridine to yield the l-acylaziridine (26). The l-acylaziridine was expected to undergo iodide catalyzed isomerization

"The hydrolysis of formamide, acetamide, propionamide and benzamide and of hydrocyanic acid, acetonitrile, propionitrile and cyanoacetic acid has been studied over a temperature range in concentrated hydrochloric acid solutions of concentration 1-1ON. Propionitrile hydrolysis was also investigated over a range of temperatures in concentrated sulphuric, hydrobromic and nitric acid solutions. The hydrolysis of propionitrile in sodium hydroxide solutions of concentration 0.3-4N has been studied. The products of thermal pyrolysis of acetonitrile and propionitrile were determined at different reaction times. The reaction of hydrogen atoms with propylene has been investigated by the Wood-Bonhoeffer method over the temperature range 30-250°C. The detection of vesicants has been studied. Means for improvement of existing paper detectors have been shown. New detectors employing dyestuffs and resin surfaces over a suitable background - customarily an aluminium foil surface - have been developed. A night detector has been devised. Heats of sorption on charcoal have been examined."

A Historical Introduction is given as background material to the problem of the existance of an ?-hydroxy-?-substituted tetronic acid as the intermediate in the oxidation of tetronic acids to ?-diketones. Three schemes are proposed by which this intermediate may be synthesized, starting with ethyl acetoacetate. In the first scheme the ?-substituted tetronic acid is oxidized by lead tetraacetate to the ?-acetoxy-?-substituted compound. In the second and third schemes, the lead tetraacetate oxidation can be applied to the ?-substituted acetoacetic ester, or the ?-substituted acetoacetic ester can be chlorinated with sulfuric chloride and then converted to the ?-acetoxy ester. Experimental work dealing with the lead tetraacetate oxidation is described, and the difficulties encountered discussed. The yields of ethyl ?-acetoxy-?-methylacetoacetate were low and thus more work is necessary before the proposed synthetic procedures are tested further.

In recent years two new experimental methods for the biologist, biochemist, chemist and medical researcher have been slowly making their way into science as important tools of research. They are paper chromatography and paper electrophoresis (also called zone electrophoresis). Both are methods of separating complex mixtures into their component parts, thereby enabling identification of each of their component fractions, or comparison of patterns of different mixtures. The biologist has utilized these tools to determine differences in the plasma, body fluids and tissues of different species and also to determine differences within the species itself. The chemist and the biochemist have used these methods to separate and identify new chemical compounds and their constituent parts. In recent years these methods have become valuable diagnostic aids in medicine and much work is being done in medical research utilizing these two tools.

According to Chemical Abstracts, the alkaloid content of Amyris elemifera has not been studied. An alcoholic extract of this plant was made and an acidified aqueous solution was purified with ether and chloroform. This aqueous extract was fractionated on an ion exchange column and the spectra of the eluates were investigated. From the spectra it appears that pteridine and purine structures are indicated for the alkaloids.

"An apparatus of original design based on scattering of light by smoke was constructed to measure the penetration of smoke filters. Methods of obtaining a suitable testing cloud for use tn the e.pparatus were investigated. Various carbon smokes were investigated and the effects of several factors, involved in the production of these smokes, on the penetretion of' the filters were determined. An oleic acid smoke generator was constructed which yielded smokes of homogeneous particle size. The stabilty of various filters to this smoke was investigated. The optimum conditions for the Manufacture of rayon-asbestos filters were determined."

Mercury contamination of food products results from contact with soil, water, and air polluted with mercury from industrial sources, as well as from the use of mercury-containing pesticides and fungicides on plants. A method was developed for extracting mercury from tobacco products. The mercury content of various tobacco products was determined, using an atomic absorption spectrophotometer.

Acid hydrolysis of an aqueous mixture of tryptophan and serine yields a spectrophotometrically constant product suitable for a quantitative analysis of tryptophan. Tschesche claims to have produced pyruvic acid from the acid hydrolysis of serine. Therefore, the direct hydrolysis of pyruvic acid with tryptophan should produce the same spectrophotometrically constant product found by the former procedure . Tschesche's hydrolysis of serine produced a dubious product and the tryptophan-pyruvate product was found to be unsuitable for a spectrophotometric quantitative technique.

The investigation of renal hypertension has led to the enzyme renin. At present renin can only be properly assayed by bioassay with a live animal which as been fitted in some manner with a device for measuring blood pressure. One common method is the rat assay. This assay requires careful anaesthesia, skilled surgical preparation of the animal, and several hours in which to complete the procedure, Even so, the assay in the hands of the most practiced technician has a precision of only 5 to 15%. It was the purpose of this senior scholar project to study several possible chemical methods of assay.

Vapor pressure determinations in a vacuum line were made first on varied compositions of acetone and pyridine and second on varied compositions of acetone and trimethylamine. These experiments were conducted in the hope of noting a negative deviation from Raoult's Law, which is indicative of adduct formation between the two substances. No such deviation was found in either case. Vapor pressure determinations were then made on varied compositions of 1) acetone and chloroform, 2) 4-heptanone and chloroform, 3) dicyclopropyl ketone and chloroform, and 4) diisopropyl ketone and chloroform. In each of these systems a negative deviation from Raoult's Law was found, and from these data values for the relative electronegatities of the propyl groups were obtained.

"A very interesting reaction was discovered by Japp (1) and his co-workers in the condensation of benzil and various aliphatic ketones of the type RCH2COCHR'R''. By isolating the intermediate products the authors were able to trace the reaction from the primary aldol condensation to the ultimate cyclopentenone ring; the reaction is represented as follows. ..."

"Cellulose is the basic constituent of all plant life, and the most important of all organic industrial raw materials. In line with the great diversity of its sources, cellulose or different origins was formerly considered to vary somewhat in its constitution, but largely through the investigations of Heuser (1) and other workers, it is now generally accepted that cellulose is the same chemical individual, irrespective of its source. Previous to a review of the work pertaining to specific volume measurements it might be well to give a survey of the physical properties of cellulose, especially those which concern the relationships existing between cellulose and liquids. ..."

"The critical temperature has been defined as that temperature beyond which a gas cannot be liquified regardless of the pressure, and, according to the old classical theory, the change from liquid to gas at the critical temperature could be made to follow a smooth transition in all physical properties such as density, viscosity, surface tension. This conclusion arises from the idea that a gas possesses no structure but a purely chaotic and random distribution and that, in the liquid, the molecules are merely under greater attractive forces due to their closer proximity. Accordingly the transition from the liquid to the gaseous state at the critical temperature should be smooth and the density of the system should be everywhere the same in the system after the critical temperature has been passed. ..."

"A. Results of analyses of tumors produced on beets by Phytomonas turnefaciens confirm the values of previous workers and show that the tumors utilize sucrose for the synthesis of protoplasm and cell wall material rather than for storage as is the case of the normal tissue. B. The first known studies on the metabolism of living slices of plant tumors have been made. c. Comparison of the metabolism of the tumor and normal tissue (of the beet root) shows striking differences in the mode and rate of sugar metabolism. Special attention has been paid to the Pasteur Effect which is found to be markedly different in the two tissues. D.A study has been made on the effect of sodium bisulphite on the respiration and fermentation of beet tissue slices. It is found to completely inhibit respiration, partially inhibit fermentation, and to cause acetaldehyde and glyceraldehyde to accumulate."

"Activated Morden Bentonite has been investigated as a vapour-phase catalyst for the decomposition of three butanediols and butanediol-2,3 diacetate. Butanediol-2,3 at low temperatures gave 85 per cent yields of butanone-2, with isobutyraldehyde and the isobutyral of butanediol-2,3 as by-products. At high temperatures, gaseous decomposition occurred producing small yields of butadiene increasing to 14.9 per cent in the presence or water vapour. Butanedlol-2,3 diacetate gave chiefly acetic acid, butanone-2, and butadiene. Highest yields (57.5 per cent) of the diene were obtained at low temperatures and at fast feed-rates. Butanediol-1,4 at low temperatures gave practically theoretical yields of tetrahydrofuran. At high temperatures, propene, butene and formaldehyde were formed with a small amount of n-butyraldehyde and condensation products. Butanediol-1,3 gave butadiene (maximum yield 28.8 per cent), propene and butene. Increase in temperature and dilution with water increased gaseous decomposition but decreased the butadiene content of the gas. n-Butyraldehyde, 1-butenol-4, n-butyral of butanediol-1,3 and formaldehyde were also formed."

"The compound l, l-di(4-chlorophenyl)-2,2,2-trichloroethane.(DDT I) has assumed great imrortanca with the discovery by the Geigy Chemical Company that it is a vary potent contact insecticide. Their results are surrnnarized in a paper by Lauger, Martin and Muller (1). Patents were issued to cover this work (2). To most cow~cn insects, it is the most powerful contact insecticide known. The Geigy paper is chiefly concerned with the testing of a large number of chemicals on various insects. DDT is included in a list of contact insecticides. These materials are effective only when the insect's body mnkes.contact with the chemical ..."