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Synthesis And In-Vitro Cell Viability/Cytotoxicity Studies Of Novel Pyrrolobenzodiazepine Derivatives, John M. Jarrett 2017 East Tennessee State University

Synthesis And In-Vitro Cell Viability/Cytotoxicity Studies Of Novel Pyrrolobenzodiazepine Derivatives, John M. Jarrett

Undergraduate Honors Theses

Pyrrolobenzodiazepines (PBDs) are a group of naturally occurring compounds that were discovered in the cultures of Streptomyces in the 1960s. Some natural PBDs discovered in these cultures, such as anthramycin and sibiromycin, were shown to possess a broad spectrum of anti-tumor activity. Since cancer is still a leading cause of death globally, the development of novel anti-proliferative derivatives of PBDs is essential for human welfare worldwide. Further synthesis and structure-activity relationship (SAR) studies of the parent natural products and their tetracyclic analogs will lead to the discovery of drug candidates. In this work, thirteen PBD analogues were synthesized using no ...


Effect Of Chain Rigidity On Network Architecture And Deformation Behavior Of Glassy Polymer Networks, Kyler Reser Knowles 2017 University of Southern Mississippi

Effect Of Chain Rigidity On Network Architecture And Deformation Behavior Of Glassy Polymer Networks, Kyler Reser Knowles

Dissertations

Processing carbon fiber composite laminates creates molecular-level strains in the thermoset matrix upon curing and cooling which can lead to failures such as geometry deformations, micro-cracking, and other issues. It is known strain creation is attributed to the significant volume and physical state changes undergone by the polymer matrix throughout the curing process, though storage and relaxation of cure-induced strains remain poorly understood. This dissertation establishes two approaches to address the issue. The first establishes testing methods to simultaneously measure key volumetric properties of a carbon fiber composite laminate and its polymer matrix. The second approach considers the rigidity of ...


Session E-1: Sharing Analogies And Demonstrations To Reinforce Chemistry Concepts, Dave DeVol, Angela Ahrendt 2017 Illinois Mathematics and Science Academy

Session E-1: Sharing Analogies And Demonstrations To Reinforce Chemistry Concepts, Dave Devol, Angela Ahrendt

Professional Learning Day

Chemistry concepts can often be difficult for students to understand, in part due to the fact that we are discussing with students things that cannot be seen (atoms and molecules!). Analogies that relate chemistry concepts to things that students are more familiar with can be a powerful way to help them understand concepts, as can demonstrations that make concepts come to life visually. We will share a few of our favorite analogies/demos, and ask that each participant share one of their favorite analogies or demos. As we realize it would be difficult for visiting teachers to bring what they ...


Session C-1: Modeling Stem Activities Into Classroom Practice, Sowmya Anjur 2017 Illinois Mathematics and Science Academy

Session C-1: Modeling Stem Activities Into Classroom Practice, Sowmya Anjur

Professional Learning Day

Students understand concepts better when they have had a chance to work hands on with relevant material. Examples will be presented from my classroom where difficult concepts have been modeled into simple experiments with considerable success in enhancing student understanding. Special focus will be given to selected topics that students seem to have the most difficulty grasping. The objective is to enable students to transfer their understanding to solve complex problems with considerable ease and apply their understanding to real world scenarios on assessments. Suggestions will also be provided for implementation of various concepts into the high school classroom.


Session A-1: Bca Method, Focusing On Mole Ratios In Stoichiometry, Carmela Jones, Deb Scarano, Anita White 2017 Illinois Mathematics and Science Academy

Session A-1: Bca Method, Focusing On Mole Ratios In Stoichiometry, Carmela Jones, Deb Scarano, Anita White

Professional Learning Day

Traditionally stoichiometry is done using dimensional analysis. Although effective, it is confusing, messy, and does not focus on mole ratios. On the other hand, the BCA method (Before-Change-After), is clear, clean, and highlights the mole ratios in a chemical reaction. Participants will collect mass data in an experiment and learn how to use a BCA table. Teachers will bring the BCA method back to their classrooms and provide an extremely useful tool for the next generation of chemistry savvy students.


Modeling And Design Of Polythiophene Gate Electrode Chemfets For Environmental Pollutant Sensing, T. V. Krishna, Jeffrey R. Jessing, Dale D. Russell, Jonathan Scaggs, Lisa R. Warner, Joe A. Hartman 2017 Boise State University

Modeling And Design Of Polythiophene Gate Electrode Chemfets For Environmental Pollutant Sensing, T. V. Krishna, Jeffrey R. Jessing, Dale D. Russell, Jonathan Scaggs, Lisa R. Warner, Joe A. Hartman

Lisa R. Warner

Water-borne pollutants such as volatile organic compounds are a serious environmental concern, which has increased the demand for chemical sensing elements. Solidstate sensors based on catalytic gate devices are a subject of current research, however they are restricted in practical applications because of their inability to operate at room temperature. Conducting polymer FETs, which employ a conducting gate polymer, have received much attention due to their unique electronic and optical properties. Polythiophene is chosen as the semi-conductive gate polymer in this work. A functional group attached to the polythiophene is used to detect analytes (i.e., mercury in this work ...


Triple Pulse Amperometry: A Method Of Detection Of Carbohydrates And Alcohols For Liquid Chromatography , Scott Hughes 2017 Iowa State University

Triple Pulse Amperometry: A Method Of Detection Of Carbohydrates And Alcohols For Liquid Chromatography , Scott Hughes

Scott Hughes

Application of a triple pulse waveform is described for the anodic detection of simple alcohols and carbohydrates at a platinum electrode. The execution of the waveform incorporates the cleaning and reactivation of the platinum electrode, by alternate anodic and cathodic polarization, with measurement of the faradaic signal for the analyte at the reduced electrode surface. The waveform is completed within 0.5-1.5 s and the sampled faradaic signal exhibits no decay with time as would be the case for amperometric detection at a constant applied potential. Calibration curves made by plotting -1/I vs. 1/C are linear. This ...


Line Of Chemical Work: Fodder, G. E. Patrick 2017 Iowa State College

Line Of Chemical Work: Fodder, G. E. Patrick

Bulletin (Iowa Agricultural Experiment Station)

The chemical laboratories being the last rooms in the Station building to be completed, were not fully equipped and ready for work until the middle of the present month (August), hence the amount of work yet accomplished is but small; and, as it is only the beginning of a line of work to be continued through several months, report upon it will be reserved for a future bulletin.


Studies On The Determination Of Sulfur As Barium Sulfate, Philip L. Blumenthal, S. C. Guernsey 2017 Iowa State College

Studies On The Determination Of Sulfur As Barium Sulfate, Philip L. Blumenthal, S. C. Guernsey

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

1. The conditions affecting the accuracy of sulfur determination by barium chloride precipitation have been studied, using potassium and sodium sulfates.

2. The effect of sodium, calcium and magnesium salts has been investigated, under conditions approximating those of insecticide analysis.

3. A definite set of conditions is quoted, which if strictly observed, will yield fairly accurate analyses. For more accurate work, a method of checking by analysis of a synthetic solution is advocated.

4. The theory of the contamination of barium sulfate by extraneous substances is discussed, and the experimental data throw further light upon the nature of the adhesion ...


Chemical Changes During Silage Formation, Ray E. Neidig 2017 Iowa State College

Chemical Changes During Silage Formation, Ray E. Neidig

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

Examination of the contents of the three types of silo in use at the Iowa Agricultural Experiment Station showed the following chemical changes during the actual period of silage formation.

1. Non-reducing sugar was rapidly changed to reducing sugar , and the latter then decreased in amount but did not disappear completely.

2. The amount of volatile acids increased daily.

3. In the concrete silo, as already demonstrated for the hollow tile and wooden stave silos, the racemic lactic acid produced showed a daily increase.

4. Alcohol was formed in small amounts in each silo.

5. Carbon dioxide developed very rapidly ...


Scitech News Volume 71, No. 1 (2017), 2017 Thomas Jefferson University

Scitech News Volume 71, No. 1 (2017)

Sci-Tech News

Columns and Reports

  • From the Editor 3

Division News

  • Science-Technology Division 5
  • Chemistry Division 8
  • Engineering Division
  • Aerospace Section of the Engineering Division 9
  • Architecture, Building Engineering, Construction and Design Section of the Engineering Division 11

Reviews

  • Sci-Tech Book News Reviews 12

Advertisements

  • IEEE 4


Chemical Studies Of The Lime-Sulfur Lead Arsenate Spray Mixture, W. E. Ruth 2017 Iowa State College

Chemical Studies Of The Lime-Sulfur Lead Arsenate Spray Mixture, W. E. Ruth

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

Mixing lead arsenate with lime sulfur results in:

1. A decrease of sulfur in solution.

2. A decrease of calcium in solution.

3. Increase of thiosulfate in solution.

4. Increase of thiosulfate in the residue.

5. Increase of sulfite in solution.

6. Formation of lead sulfide.

7. Formation of a compound containing arsenic and sulfur but insoluable in the lime-sulfur solution,—probably lead thioarsenate.


Lactic Acid In Corn Silage, Arthur W. Dox, Ray E. Neidig 2017 Iowa State College

Lactic Acid In Corn Silage, Arthur W. Dox, Ray E. Neidig

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

In a previous bulletin of this series a study of the volatile aliphatic acids of corn silage was reported in detail. It was shown that acetic and propionic acids are normally present in considerable amount, while higher members of the series, as butyric, seemed to impart undesirable qualities, and their presence might be taken as evidence of incipient spoiling. The total volatile acid recovered by distillation did not, however, in any case account for all of the acidity observed by direct titration of the original silage juice. The difference represents therefore non-volatile acid, which heretofore has been assumed to consist ...


Amino Acids And Acid Amides As Sources Of Ammonia In Soils, S. L. Jodidi 2017 Iowa State College

Amino Acids And Acid Amides As Sources Of Ammonia In Soils, S. L. Jodidi

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

l'he nitrogen recognized as one of the most important elements for plants, if not the most necessary, is being studied and discussed by many investigators ana among them the opinion is quite general that there is a considerable difference between the various forms of nitrogen. this is particularly true of soil nitrogen. Wile in some soils the nitrogen is readily ammonified and furter ifled and further oxidized to nitrites and nitrates, it does not undergo those processes in other soils. In other words, soil nitrogen is available or can easily be made available for plants in some cases, in ...


Volatile Aliphatic Acids Of Corn Silage, Arthur W. Dox, Ray E. Neidig 2017 Iowa State College

Volatile Aliphatic Acids Of Corn Silage, Arthur W. Dox, Ray E. Neidig

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

1. Volatile aliphatic acids were found in considerable amount in all samples of good silage which we examined.

2. Acetic acid comprised about nine tenths of the total volatile acid present.

3. Propionic acid was next in importance to acetic.

4. Butyric acid was found in considerable amounts only in samples where some slight indications of spoiling were otherwise apparent.

5. Alcohols were found in appreciable quantities, but esters only in traces.

6. As far as volatile acids and alcohols are concerned, no differences were noted which could be attributed to differences in the type and construction of the silo.


Two Homologous Intermetallic Phases In The Na–Au–Zn System With Sodium Bound In Unusual Paired Sites Within 1d Tunnels, Saroj L. Samal, Qisheng Lin, John D. Corbett 2017 Iowa State University

Two Homologous Intermetallic Phases In The Na–Au–Zn System With Sodium Bound In Unusual Paired Sites Within 1d Tunnels, Saroj L. Samal, Qisheng Lin, John D. Corbett

Qisheng Lin

The Na–Au–Zn system contains the two intermetallic phases Na0.97(4)Au2Zn4 (I) and Na0.72(4)Au2Zn2 (II) that are commensurately and incommensurately modulated derivatives of K0.37Cd2, respectively. Compound I crystallizes in tetragonal space group P4/mbm (No. 127), a = 7.986(1) Å, c = 7.971(1) Å, Z = 4, as a 1 × 1 × 3 superstructure derivative of K0.37Cd2 (I4/mcm). Compound II is a weakly incommensurate derivative of K0.37Cd2 with a modulation vector q = 0.189(1) along c. Its structure was solved in superspace group P4/mbm(00g)00ss, a = 7 ...


Superconducting Properties Of Rh 9 In 4 S 4 Single Crystals, Udhara S. Kaluarachchi, Qisheng Lin, Weiwei Xie, Valentin Taufour, S. L. Bud’ko, Gordon J. Miller, Paul C. Canfield 2017 Iowa State University

Superconducting Properties Of Rh 9 In 4 S 4 Single Crystals, Udhara S. Kaluarachchi, Qisheng Lin, Weiwei Xie, Valentin Taufour, S. L. Bud’Ko, Gordon J. Miller, Paul C. Canfield

Qisheng Lin

The synthesis and crystallographic, thermodynamic, and transport properties of single crystalline Rh9In4S4 were studied. The resistivity, magnetization, and specific heat measurements all clearly indicate bulk superconductivity with a critical temperature, Tc∼2.25 K. The Sommerfeld coefficient γ and the Debye temperature (ΘD) were found to be 34 mJ mol−1 K−2 and 217 K, respectively. The observed specific heat jump, ΔC/γTc=1.66, is larger than the expected BCS weak coupling value of 1.43. Ginzburg-Landau (GL) ratio of the low-temperature GL-penetration depth, λGL≈5750 Å, to the GL-coherence length, ξGL≈94 Å, is large: κ ∼60 ...


Synthesis, Structure, And Bonding Of Sc4mgxcu15-Xga~7.5 (X = 0, 0.5): Two Incommensurately Modulated Scandium Substitution Derivatives Of Cubic Mg2cu6ga5, Qisheng Lin, Sven Lidin, John D. Corbett 2017 The Ames Laboratory

Synthesis, Structure, And Bonding Of Sc4mgxcu15-Xga~7.5 (X = 0, 0.5): Two Incommensurately Modulated Scandium Substitution Derivatives Of Cubic Mg2cu6ga5, Qisheng Lin, Sven Lidin, John D. Corbett

Qisheng Lin

The substitution of scandium for magnesium in Mg2Cu6Ga5 (Mg2Zn11-type) yields an irrational superstructure phase that includes the refined compositions, Sc4Mg0.50(2)Cu14.50(2)Ga7.61(2) and Sc4Cu14.76(2)Ga7.51(2). These crystallize in Cmmm, a = ∼8.31 Å, b = ∼21.72 Å, c = ∼8.30 Å. The structures feature Sc2 dimers, Cu6 octahedra, a 3D CuGa (Cu12Ga2) framework, and arachno gallium-centered Cu4Ga6 icosahedra that are condensed into zigzag chains. The arrangement of these building blocks exhibits a topologic relationship to Mg2Cu6Ga5. Further studies reveal that the quaternary compound exhibits incommensurate modulations along a, with q ...


M3(Au,Ge)19 And M3.25(Au,Ge)18 (M = Ca, Yb): Distinctive Phase Separations Driven By Configurational Disorder In Cubic Ycd6-Type Derivatives, Qisheng Lin, John D. Corbett 2017 The Ames Laboratory

M3(Au,Ge)19 And M3.25(Au,Ge)18 (M = Ca, Yb): Distinctive Phase Separations Driven By Configurational Disorder In Cubic Ycd6-Type Derivatives, Qisheng Lin, John D. Corbett

Qisheng Lin

Exploratory syntheses in the M−Au−Ge (M = Ca, Yb) systems have led to the discovery of two cleanly separated non-stoichiometric phases M3Au∼14.4Ge∼4.6 (I) and M3.25Au∼12.7Ge∼5.3 (II). Single crystal X-ray studies reveal that both (space group Im3̅) feature body-centered-cubic packing of five-shell multiply endohedral clusters that resemble those in the parent YCd6 (= Y3Cd18) and are akin to approximate phases in other quasicrystal systems. However, differences resulting from various disorders in these are distinctive. The innermost cluster in the M3Au∼14.4Ge∼4.6 phase (I) remains a disordered tetrahedron, as ...


Li14.7mg36.8cu21.5ga66: An Intermetallic Representative Of A Type Iv Clathrate, Qisheng Lin, John D. Corbett 2017 The Ames Laboratory

Li14.7mg36.8cu21.5ga66: An Intermetallic Representative Of A Type Iv Clathrate, Qisheng Lin, John D. Corbett

Qisheng Lin

Synthetic explorations in the quaternary Li−Mg−Cu−Ga system yield the novel intermetallic Li14.7(8)Mg36.8(13)Cu21.5(5)Ga66 [P6̅m2, Z = 1, a = 14.0803(4) Å, c = 13.6252 (8) Å] from within a limited composition range. This contains a unique three-dimensional anionic framework consisting of distinct interbonded Ga12 icosahedra, dimerized Li@(Cu,Mg)10Ga6 icosioctahedra, and 15-vertex Li@(Cu,Mg)9Ga6 and Li@Cu3Ga12 polyhedra. These polyhedral clusters are hosted by M20 (512), M24 (51262), and M26 (51263) (M = Li/Mg) cages, respectively. The geometries and arrangements of these cages follow those ...


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