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Silage And Silage Fermentation, A. R. Lamb 2017 Iowa State College

Silage And Silage Fermentation, A. R. Lamb

Bulletin (Iowa Agricultural Experiment Station)

There would be much less spoilage and waste of silage if the more than 22,000 farmers in Iowa who put up this valuable feed understood just what happens in the fermentation process, instead of following directions in “cook book” style. There would also be more use of other crops than corn for silage, especially in cases of emergency, if the merits of some of them for this purpose were known. Conditions are not always normal and favorable for the best results in making silage, and a knowledge of the principles upon which the proper preservation of silage depends is ...


Crystal Engineering Of Active Pharmaceutical Ingredients With Low Aqueous Solubility And Bioavailability, Jenna M. Skieneh 2017 The University of Western Ontario

Crystal Engineering Of Active Pharmaceutical Ingredients With Low Aqueous Solubility And Bioavailability, Jenna M. Skieneh

Electronic Thesis and Dissertation Repository

Approximately 75% of new molecular entities approved by the Food and Drug Administration (FDA) for use in the pharmaceutical industry are found to have poor aqueous solubility. This undesirable attribute leads to consequences such as higher doses required to reach therapeutic levels, greater vulnerability to food effects, lesser fraction absorbed in the small intestine and damage to the environment due to increased quantity of excretion. The addition of an excipient (i.e. a FDA approved inactive ingredient) to the molecular structure of an active pharmaceutical ingredient (API) through intermolecular bonding is of growing interest because the properties of the API ...


Pasteurization Of Cream For Buttermaking, M. Mortensen, W. G. Gaessler, W. H. Cooper 2017 Iowa State College

Pasteurization Of Cream For Buttermaking, M. Mortensen, W. G. Gaessler, W. H. Cooper

Bulletin (Iowa Agricultural Experiment Station)

In some European countries the pasteurization of cream for buttermaking is extensively practiced. Butter manufacturers in the United States have long recognized that this is a desirable procedure and they have written numerous letters to the experiment stations seeking information regarding it. In many cases it has been more or less difficult to answer these inquiries because of the comparatively small amount of experimental work which has been done along this line.

The purpose of the experiments herein reported was to determine the value of pasteurization to those engaged in the manufacture of butter. In this connection the effect of ...


Influence Of Condimental Stock Foods On The Digestibility Of A Corn Ration Fed To Swine., Louis G. Michael, W. J. Kennedy 2017 Iowa State College

Influence Of Condimental Stock Foods On The Digestibility Of A Corn Ration Fed To Swine., Louis G. Michael, W. J. Kennedy

Bulletin (Iowa Agricultural Experiment Station)

Every stock food manufacturer claims that his particular brand of food will give greater gains or cheaper gains when fed in addition to a ration than that ration will give when fed alone. This claim is based upon the assumption that the spices, seeds, barks, roots, and herbs of which each food is said to be “scientifically compounded,” either directly stimulate the glands of the stomach and intestines which have to do the work of digesting and assimilating the ration; or else that the compounds act indirectly on these glands by toning up the entire animal system, purifying the blood ...


The Influence Of Feeding Sugar Beets And Mangels To Breeding Animals, With Special Referance To The Formation Of Renal And Urinary Calculi., Louis G. Michael 2017 Iowa State College

The Influence Of Feeding Sugar Beets And Mangels To Breeding Animals, With Special Referance To The Formation Of Renal And Urinary Calculi., Louis G. Michael

Bulletin (Iowa Agricultural Experiment Station)

In the fall of 1904, Doctor White, a Short-horn bull owned by the Iowa State College, died. A post mortem examination showed his kidneys to contain a large number of calculi, some of which are shown in figure 1.

These calculi are composed principally of lime phosphate but contain larger or smaller amounts of all the urinary constituents as acculusions.

Up to the time of his death Doctor White had received a normal hay and grain ration to which roots (mangel wurtzels) had been added. Reference has from time to time been made in farm journals both in this country ...


Anti-Biofilm Activity Of A Self-Aggregating Peptide Against Streptococcus Mutans, Julia Ansari, Nabil M. Abraham, Jenna Massaro, Kelsey Murphy, Jillian E. Smith-Carpenter, Erol Fikrig 2017 Fairfield University

Anti-Biofilm Activity Of A Self-Aggregating Peptide Against Streptococcus Mutans, Julia Ansari, Nabil M. Abraham, Jenna Massaro, Kelsey Murphy, Jillian E. Smith-Carpenter, Erol Fikrig

Jillian Smith-Carpenter

Streptococcus mutans is the primary agent of dental cavities, in large part due to its ability to adhere to teeth and create a molecular scaffold of glucan polysaccharides on the tooth surface. Disrupting the architecture of S. mutans biofilms could help undermine the establishment of biofilm communities that cause cavities and tooth decay. Here we present a synthetic peptide P1, derived from a tick antifreeze protein, which significantly reduces S. mutans biofilm formation. Incubating cells with this peptide decreased biofilm biomass by approximately 75% in both a crystal violet microplate assay and an in vitro tooth model using saliva-coated hydroxyapatite ...


How Strongly Do Oysters Stick?, Nicolás M. Morato, Andrés M. Tibabuzo, Jonathan J. Wilker 2017 Universidad de Los Andes - Colombia

How Strongly Do Oysters Stick?, Nicolás M. Morato, Andrés M. Tibabuzo, Jonathan J. Wilker

The Summer Undergraduate Research Fellowship (SURF) Symposium

Biological adhesives are a type of interfacial material that has incredible potential to generate new biomimetic compounds that can replace current strong, but toxic, adhesives. Therefore, a study of the chemical composition and mechanical properties of those bio-adhesives is necessary. However, in the case of oysters, despite known chemical characterization of the adult’s adhesive, there are almost no studies on its mechanical properties. Furthermore, there is no available information on the adhesive properties of spat (oysters in their larvae state). Herein, we present the first mechanical characterization of the spat adhesive, measuring its adhesion strength by hydrodynamic determination using ...


Applying Machine Learning To Computational Chemistry: Can We Predict Molecular Properties Faster Without Compromising Accuracy?, Hanjing Xu, Pradeep Gurunathan, Lyudmila Slipchenko 2017 Purdue University

Applying Machine Learning To Computational Chemistry: Can We Predict Molecular Properties Faster Without Compromising Accuracy?, Hanjing Xu, Pradeep Gurunathan, Lyudmila Slipchenko

The Summer Undergraduate Research Fellowship (SURF) Symposium

Non-covalent interactions are crucial in analyzing protein folding and structure, function of DNA and RNA, structures of molecular crystals and aggregates, and many other processes in the fields of biology and chemistry. However, it is time and resource consuming to calculate such interactions using quantum-mechanical formulations. Our group has proposed previously that the effective fragment potential (EFP) method could serve as an efficient alternative to solve this problem. However, one of the computational bottlenecks of the EFP method is obtaining parameters for each molecule/fragment in the system, before the actual EFP simulations can be carried out. Here we present ...


Mobility Characteristics Of Azithromycin In Soil, Ryan Minter, Jihyun Kim, Linda Lee 2017 Purdue University

Mobility Characteristics Of Azithromycin In Soil, Ryan Minter, Jihyun Kim, Linda Lee

The Summer Undergraduate Research Fellowship (SURF) Symposium

The presence of pharmaceutical and personal care products (PPCPs) in the environment has become a widespread problem in recent decades. Azithromycin, a macrolide antibiotic commonly prescribed for infections in humans, has been detected in waste treatment plant discharge and surface waters across the world. Data on the mobility characteristics of azithromycin in soil is scarce, and further studies must be performed to explore the potential for azithromycin leaching to groundwater or becoming available for plant uptake. In this study, azithromycin sorption isotherms were measured on eight soils varying in pH, organic carbon content, and clay content. Soil was equilibrated with ...


Exploration Of A Unique Uranium Mediated Carbon-Carbon Radical Coupling Reaction, Zhengjia Tong, Caleb J. Tatebe, John J. Kiernicki, Matthias Zeller, Suzanne C. Bart 2017 Purdue University

Exploration Of A Unique Uranium Mediated Carbon-Carbon Radical Coupling Reaction, Zhengjia Tong, Caleb J. Tatebe, John J. Kiernicki, Matthias Zeller, Suzanne C. Bart

The Summer Undergraduate Research Fellowship (SURF) Symposium

Designing an efficient nuclear fuel cycle has motivated decades of research on aqueous phase uranium chemistry. As such, studies are often limited by the formation of unreactive uranium oxides and/or solubility issues. Carrying out reactions in non-aqueous solvents addresses said problems and enables explorations into previously unattainable reactivity and fundamental properties of uranium. One such feat is the syntheses of uranium alkyls, as they permit research into bond interactions between uranium and carbon. Considering uranium’s oxophilicity, we investigated the relatively understudied uranium(III) alkyls—both their reactivity and reaction mechanism—towards oxygen-containing reagents. In an inert atmosphere, various ...


Parallelization Of Molecular Docking Algorithms Using Cuda For Use In Drug Discovery, Brandon Stewart, Jonathan Fine, Gaurav Chopra PhD 2017 Purdue University

Parallelization Of Molecular Docking Algorithms Using Cuda For Use In Drug Discovery, Brandon Stewart, Jonathan Fine, Gaurav Chopra Phd

The Summer Undergraduate Research Fellowship (SURF) Symposium

Traditional drug discovery methodology uses a multitude of software packages to design and evaluate new drug-like compounds. While software packages implement a wide variety of methods, the serial (i.e. single core) implementation for many of these algorithms, prohibit large scale docking, such as proteome-wide docking (i.e. thousands of compounds with thousands of proteins). Several docking algorithms can be parallelized, significantly reducing the runtime of the calculations, thus enabling large-scale docking. Implementing algorithms that take advantage of the distributed nature of graphical processing units (GPUs) via the Compute Unified Device Architecture (CUDA) enables us to efficiently implement massively parallel ...


Temperature-Dependent Exciton Dynamics Of Superacid Treatment In Monolayers Of The Metal Dichalcogenide Mos2, Mingwei Zhou, Long Yuan, Jordan Snaider, Libai Huang 2017 Purdue University

Temperature-Dependent Exciton Dynamics Of Superacid Treatment In Monolayers Of The Metal Dichalcogenide Mos2, Mingwei Zhou, Long Yuan, Jordan Snaider, Libai Huang

The Summer Undergraduate Research Fellowship (SURF) Symposium

To improve optoelectronic semiconductor materials, one of the most efficient research areas is the two-dimensional (2D) transition-metal dichalocogenides (TMDCs). It has been shown that organic nonoxidizing superacid bis(trifluoromethane)sulfonamide (TFSI) treatment of molybdenum disulfide (MoS2) monolayer could uniformly enhance its photoluminescence by more than two orders of magnitude and also extend the lifetime of excitons. This could greatly improve the efficiency of the solar energy usage, but the mechanism behind it has not been fully understood. Extreme low temperatures (approximately 7K), which slow the surface exciton mobility, were applied to investigate the changes of treated MoS2 monolayer ...


Synthesis Of Healable Organic Semiconductor Through Dioxaborolane Bond, Junchen Liu, William W. Mcnutt, Jianguo Mei 2017 Purdue University

Synthesis Of Healable Organic Semiconductor Through Dioxaborolane Bond, Junchen Liu, William W. Mcnutt, Jianguo Mei

The Summer Undergraduate Research Fellowship (SURF) Symposium

The field of organic semiconductors have gained enormous attention the past few decades. Organic materials offer numerous advantages over their inorganic counterparts. Recently a number of works have demonstrated organic semiconductors with healable properties. We aim to investigate the healable ability of an organic semiconductor by mimicking a vitrimer system through the reversible dioxaborolane bond. Vitrimers are polymers with reversible crosslink system. It has been reported that the use of the borane-oxygen bond as the crosslink showed good mechanical performance. The electrical properties will be inspected for the vitrimer-like polymer. In this report we describe a Diketopyrrolopyrrole base polymer incorporating ...


Condimental Stock Foods And Tonics., Louis G. Michael, H. O. Buckman 2017 Iowa State College

Condimental Stock Foods And Tonics., Louis G. Michael, H. O. Buckman

Bulletin (Iowa Agricultural Experiment Station)

During the past eighteen months the Chemical Section has received for examination 43 different brands of Condimental Stock Foods. Nearly every drug store and every feed store, in addition to a large number of agents, are offering this class of foods to the consuming public. The amount annually expended for these commodities runs into thousands of dollars. The “virtue” lying in the drugs of which such foods and tonics are compounded is so varied that (if the statements of some Condimental Food Companies are reliable) almost any one of these products will cure Texas Fever” which is caused by a ...


Investigation Of Concentrated Commercial Feed Stuffs As Sold In Iowa., Louis G. Michael 2017 Iowa State College

Investigation Of Concentrated Commercial Feed Stuffs As Sold In Iowa., Louis G. Michael

Bulletin (Iowa Agricultural Experiment Station)

In March, 1905, a circular letter over the signature of Director Charles F. Curtiss was sent to five thousand dealers in the state, including feed and grain dealers, druggists, merchants and millers. The letter called attention to the condition in which the feed-stuffs of the state were believed to be; and asked for information relative to the classes and.amounts of feed-stuffs sold. The request was also made that samples of feeds be submitted for analysis. In response to these five thousand letters, we received only three hundred and six replies, and a few over a hundred samples most of ...


Breakfast Foods., J. B. Weems, C. E. Ellis 2017 Iowa State College

Breakfast Foods., J. B. Weems, C. E. Ellis

Bulletin (Iowa Agricultural Experiment Station)

In the last few years various cereal products known as Breakfast Foods have been- placed on the market. Many of these foods have been prepared in an excellent manner, placed in clean boxes and are attractive to the consumer. The breakfast foods are regarded by many as a very expensive form of food material, while others, considering the palatableness of these preparations and the amount of milk and sugar consumed as part of the meal say that they are economical when everything is considered.


Octahedral Ruthenium(Ii) Complexes For C-H Bond Activation And Olefin Hydroarylation, Patrick Z. Zdunek 2017 University of Tennessee at Chattanooga

Octahedral Ruthenium(Ii) Complexes For C-H Bond Activation And Olefin Hydroarylation, Patrick Z. Zdunek

Honors Theses

The study of inert C-H bond activation of hydrocarbons has been gaining interest. As these hydrocarbons are used in the production of many consumables such as fuel, plastics, and detergents, it is necessary to efficiently utilize the finite quantity of petroleum feedstocks. Transition metal complexes are incorporated as catalysts into synthetic routes to create new C-X (X = C, N, O) bonds in order to increase the chemical value of organic molecules. The complex [Ru(η6-p-cymene){P(OCH2CF3)3}(Ph)(OTf)] (1) (P{OCH2CF3}3 = tris(2,2,2-trifluoroethyl) phosphite, Ph = phenyl, OTf = trifluoromethanesulfonate) was prepared and tested for functionality as ...


Synthesis And Catalytic Evaluation Of Novel C-Alpha-Methyl-Beta-Proline Analogues, And Concise Synthetic Approach To Nh-Fmoc-S-Trityl-C-Alpha-Methyl Cysteine, Hari Kiran Kotapati 2017 University of Southern Mississippi

Synthesis And Catalytic Evaluation Of Novel C-Alpha-Methyl-Beta-Proline Analogues, And Concise Synthetic Approach To Nh-Fmoc-S-Trityl-C-Alpha-Methyl Cysteine, Hari Kiran Kotapati

Dissertations

In the field of chemistry there is a growing demand for small molecule organocatalysts such as amino acids, more specifically proline and its analogues, which could catalyze various key chemical reactions in the synthesis of several biologically important molecules. Even though natural proline is reported to catalyze various chemical reactions, its use as organocatalyst is limited mainly due to the solubility issues in the reaction media and high catalyst loadings, which is not very ideal for bulk scale manufacturing. To address these limitations we planned to develop unnatural analogues of proline that could catalyze the reactions with lower catalyst loadings ...


Enantioselective Γ- And Δ -Borylation Of Unsaturated Carbonyl Derivatives: Synthesis, Mechanistic Insights, And Applications., Gia L. Hoang 2017 University of Nebraska-Lincoln

Enantioselective Γ- And Δ -Borylation Of Unsaturated Carbonyl Derivatives: Synthesis, Mechanistic Insights, And Applications., Gia L. Hoang

Student Research Projects, Dissertations, and Theses - Chemistry Department

Chiral boronic esters are valuable synthetic intermediates widely used in a variety of stereospecific transformations. Transition metal-catalyzed asymmetric hydroboration (CAHB) of alkenes is among the most popular methods for their preparation. Enantioselective hydroboration of activated alkenes (i.e., vinyl arene derivatives or conjugated carbonyl compounds) have been extensively studied by many research groups. We, on the other hand, are interested in enantioselective hydroboration of unactivated alkenes utilizing coordinating functional groups (e.g., carbonyl derivatives) to give functionalized, chiral boronic esters. While conjugate addition and C–H activation methodologies provide efficient alternatives to CAHB for enantioselective beta-borylation of carbonyl compounds, direct ...


Miniaturization Of Linear Ion Traps And Ion Motion Study In A Toroidal Ion Trap Mass Analyzer, Ailin Li 2017 Brigham Young University

Miniaturization Of Linear Ion Traps And Ion Motion Study In A Toroidal Ion Trap Mass Analyzer, Ailin Li

All Theses and Dissertations

I describe the miniaturization of a linear-type ion trap mass spectrometer for possible applications in portable chemical analysis, and demonstrate the advantages of using lithographically patterned electrode plates in realizing an ion trap with dimension r0 less than 1 mm. The focus of the work was to demonstrate the viability and feasibility of the patterned electrode approach to trap miniaturization, and also to discover potential obstacles to its use. Planar ceramic substrates were patterned with metal electrodes using photolithography. Plates that were originally used in a linear trap with a half-spacing (r0) of 2.19 mm were positioned ...


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