Scientific Program

Conference Series Ltd invites all the participants across the globe to attend 3rd World Chemistry Conference Dallas, Texas, USA.

Day :

Speaker

Chair

Zdzisław M Migaszewski

Jan Kochanowski Univ., Poland

Speaker

Co-Chair

Jochen Balbach

Martin-Luther-University Halle-Wittenberg, Germany

Speaker
Biography:

Iason Rusodimos has completed his BS in Electrical Engineering (1976), MS in Electrical Engineering (1977), MS in Math (1983), MS in Physics (1984), all of which are from the Georgia Institute of Technology. Since 1986, he joined the Faculty of Georgia Perimeter College, which has been recently consolidated with Georgia State University, teaching mostly Calculus, Differential Equations, and Linear Algebra courses. In addition to developing various instructional methods associated with STEM education, he has long been interested in effective applications of Math to Science and Engineering. Recently, he has been interested in application of derivatives approach in Science and Engineering, in kinetic processes, as illustrated in this presentation. Major area of research has been solving partial differential equations on a physical or mechanical system associated with elasticity, and on chemical systems of heterogeneous electron-transfer kinetics.

Abstract:

Theoretical expressions for the first, second and third derivatives of voltammetric curves are analytically derived for reversible, quasi-reversible, and irreversible processes under spherical diffusion. The shapes of the curves are analyzed in terms of peak-potentials, peak-currents, and peak-widths, and the differences and ratios among them. The results obtained with spherical electrodes are compared with those with the planar electrodes, which exhibits striking differences between two electrodes. Derived parameters – such as ratios of peak-currents (iap/icp), and ratios of half-peak-widths (Wa½/Wc½), and ratios of the differences in peak potentials (ΔEap/ΔEcp), for various derivatives are analyzed. As electrode sphericity increases, these ratios (i.e., measures of symmetry in the curves) for a quasi-reversible and irreversible electron transfer process approaches to one, which is the same as that for a simple reversible electrode process on a planar electrode. Namely, the asymmetry which was exhibited on planar electrodes for quasi and irreversible processes disappears on a spherical electrode. This suggests that the planar electrode is better suited for kinetic study of slower electron transfer than spherical electrodes for this derivative approach.

Speaker
Biography:

Agnieszka Gałuszka is an Environmental Geochemist specializing in Geochemical background assessment. Her research interests focus on determination of trace elements in different environmental samples (e.g. waters, soils, sediments, plants etc.) and on pinpointing possible sources and the fate of these elements in the environment with the emphasis on anthropogenic pollution. Her publications cover a wide range of topics from case studies on environmental quality oriented issues, acid mine drainage, mineralogy, to green analytical chemistry.

Abstract:

The acid mine drainage areas represent a type of environment enriched in rare earth elements (REE) caused by an increased mobility of REE at a low pH of water and soil. Rare earth elements are not essential to plants and may cause reduced biomass in native plants. A typical total REE concentration in a reference plant is 1131 µg/kg. However, there are substantial differences in REE levels among the plant species. The purpose of this study was to compare the REE concentrations in plant samples collected at different sites in the acid mine drainage area in south-central Poland with typical REE content in plant material and to assess their REE accumulation potential. Twenty-six samples of above-ground parts of four vascular plant species (Juncus effusus, Matricaria chamomilla, Salix alba and Tussilago farfara) and two moss species (Pleurozium schreberi and Drepanocladus aduncus) were collected in 2015 and 2016 in the study area. The samples were rinsed with distilled water, air-dried, ground and digested in a closed microwave system using HNO3 (1:1)/H2O2 solution in the ratio of 8 ml/1 ml. The digested samples were analyzed for REE using ICP-QMS instrument (model ELAN DRC II, PerkinElmer). Accuracy of the measurement was assessed with two plant-matrix reference materials: NIST 1573a (Tomato leaves) and NIST 1575a (Pine needles). Most of the plant samples showed total REE concentrations in the range of 69–3413 µg/kg. Only two moss samples and one sample of vascular plant (T. farfara) were extremely enriched in REE (23, 066-28, 133 µg/kg). The study showed that plants growing in temporary submerged conditions more efficiently took up and accumulated an excessive amount of REE. High levels of REE in moss species showing high ion adsorption/desorption capacities may be important for reclamation of abandoned tailings piles by revegetation or REE recovery.

Ajay Sharma

Fundamental Physics Society, India

Title: Inconsistencies in theoretical analysis of archimedes principle

Time : 12:10-12:35

Speaker
Biography:

Ajay Sharma started his career as Lecturer Physics at DAV College Chandigarh. Currently, he is research scholar ( having passed BSc. And Msc. Degree with first division) at Central University of Himachal Pradesh Dharmashala. His natural field of interest is fundamental law of science. In one of his papers, he had generalized Archimedes Principle from its theoretical calculation which is part of both physical chemistry and basic physics. He has proved systematically that effects of the shape of body and viscosity of fluid are missing from Archimedes Principle. He is trying to confirm his theoretical predictions experimentally at National Physical Laboratory, New Delhi. He has already published about 60 articles in international journals, conferences and peer review scientific magazines. His recent conference was in Moscow in the year 2014. Currently is secretary of the Fundamental Physics Society, Shimla.

Abstract:

The consistency of mathematical equation requires if values of (n-1) variables are given then the value of nth variable can be calculated. The value of nth variable must turn out definite and logical, otherwise, there is serious mathematical inconsistency in the law or equation it is based. The predictions of the equation are experimentally checked for final confirmation. Under some feasible conditions from Archimedes principle in case of completely submerged balloons, the nth variable is not determined if (n-1) variables are given. Under these conditions, for example, the density of material filled inside the balloon (and that of the sheath) is equal to the density of the fluid (say water) in which balloon floats is the same. Under these conditions, the density of the medium (Dm), the volume of the sheath, density of sheath etc. are correctly determined mathematically. But the volume of material filled in the sheath comes out be indeterminate i.e. V =0/0. Thus the principle is generalized i.e. upthrust is proportional to the weight of fluid displaced (U=fVDg). Then repeating the same calculations with identical values of parameters, then exact value of volume filled inside the balloon i.e. V=V is obtained. Thus the generalized form is theoretically justified. Further analysis finds that the where f is the coefficient of proportionality accounts for the shape of body, the viscosity of the medium, the magnitude of medium and body or particle, nature of interactions, surface tension, and other relevant elusive effects etc. Archimedes principle excludes these values. Some specific experiments are suggested to experimentally measure the value of f. Such specific and diverse experiments have not been conducted in the existing literature, which is novelty and significance of the experiments. These experiments have nobility as never reported in the literature; nonetheless, the principle is 2267 years old. The contradictory results from Archimedes principle have been found in ultracentrifugation experiments involving nanoparticles.

Hanseul Kim

Korea Institute of Industrial and Technology

Title: Production of oil and wax blends from fast pyrolysis of plastic wastes using a fluidized bed reactor

Time : 12:35-13:00

Speaker
Biography:

Hanseul Kim has completed his Bachelor’s degree in Chemical Engineering at the Kwangwoon University in Seoul, Korea. He has worked for a Lead frame manufacturing company for 6 months. He has completed his Master’s degree from University of Science and Technology (UST). Currently, he is working for Korea Institute of Industrial Technology (KITECH) as a Researcher.

Abstract:

The use of plastics is increasing, and the disposal of plastic waste is becoming a serious problem. Plastic wastes are not only poorly decomposable but also cause various pollution problems. Therefore, effective treatment of waste plastics is needed. In the case of waste plastics whose constituents are not uniform, it is best to make hydrocarbons using pyrolysis reactions.

In this paper, the pyrolysis characteristics of waste plastics were investigated using a fluidized bed pyrolysis reactor. First, thermal decomposition characteristics and trends of the waste plastics were analyzed through TGA, elemental analysis, proximity analysis of samples and XRF (X-ray fluorescence) analysis of ash. In the pyrolysis fluidized bed reactor(Fig1), the effects of various reaction parameters, like reaction temperature, the feed rate of waste plastics, and residence time after the reaction was investigated. And the complexed organic compounds between the product oils on the different experimental parameters and a detailed analysis of the oils were also investigated.

Chih-Chieh Hsu

National Yunlin University of Science and Technology, Taiwan

Title: Interface-Controlled resistive switching behavior of molybdenum oxide semiconductor

Time : 13:50-14:25

Speaker
Biography:

Chih-Chieh Hsu has his expertise in semiconductor process and semiconductor device physics. He has much experience in thin film transistors, resistive memories, and sol-gel processes. He has published 15 SCI journal papers in the past three years. This approach will be applicable to future high-performance semiconductor devices.

Abstract:

Floating gate memory has been widely used in non-volatile data storage, because it has fast data write/read capability, high-capacity storage, low-power consumption, and high endurance. However, recently, resistive random access memory (RRAM) has been proposed to be a new candidate for nonvolatile memory device technology, because it not only has the advantages that are mentioned above but also has a lower production cost than that of a floating gate memory due to its simple metal semiconductor metal (MSM) structure. This study demonstrated a high-performance interface-controlled MoOx RRAM fabricated by using a radio-frequency (RF) sputter. A glass substrate was firstly cleaned by ultrasonic agitation in acetone, ethanol and de-ionized water, respectively. Then, Pt was deposited as a bottom electrode and a molybdenum oxide thin film was subsequently deposited by RF sputtering a MoO3 target at oxygen flow rates of 0, 6, 9, 12,15 sccm. The argon flow rate was 12 sccm, the RF power was 40 W, and the working pressures was 3×10-3 torr. Finally, Al top electrodes were deposited on the MoOx layer by evaporation and patterned by a shadow mask. The MoO3 RRAM exhibits a significant memory window of 102 for 500 operations. The resistive switching mechanism was found to be dominated by formation/dissociation of an interfacial AlOx layer between Al electrode and MoOx active layer. The carrier transport mechanism was also investigated. The morphologies and thicknesses of the MoOx films were measure by using a scanning electron microscope (SEM). An X-ray diffraction (XRD) was employed to examine the crystallinity of the MoOx films. A UV-visible spectroscopy was used to study the transparency and the optical band gap. chemical structures of MoOx films were clarified by using X-ray photoelectron spectroscopy (XPS). This approach can be applied to future high-performance RRAM technology.

Biography:

Abstract:

When using a sol-gel process to synthesize semiconductor thin films, toxic solvents and high-temperature sintering processes were usually required. Although toxic solvents are generally chemical active and solutes normally have higher solubilities to these solvents, they are harmful to human bodies and environmentally unfriendly. Besides, high-temperature sintering processes will arise high manufacturing cost, much time consumption and low process compatibility. This study synthesized tin oxide (SnOx) semiconductor thin films by using a sol-gel process. The precursor solution was obtained by using a non-toxic solvent of C2H5OH. After Cl2Sn2, H2O was dissolved in the C2H5OH, this mixed solution was continuously stirred at 80℃ for 24 hours and it was aged at room temperature for 1-2 days. The solution was opaque initially and turned into transparent after stirring and the aging process. A SnOx thin film was deposited on the ITO substrate by using a spin coating process. Then, the deposited SnOx film was cured on a hotplate at 70℃ for 60s to remove the solvent. We also investigated concentration effects on SnOx characteristics. Current-voltage curves of the optimal SnOx thin film exhibit significant bipolar resistive switching behavior and highly stable endurance characteristic. The carrier transport mechanism was also studied. An X-ray photoelectron spectroscopy (XPS) was used to examine chemical structures of the deposited SnOx films. The oxidation number of Sn and concentrations of lattice oxygen and non-lattice oxygen were explored. The crystallinity of the SnOx film was examined by using X-ray diffraction (XRD) analysis. Fourier transform infrared (FTIR) was utilized to obtain chemical bonds. A UV-visible spectroscopy was employed to study the transparency and the optical band gap. This approach has advantages of simplicity, low-cost and high throughput, and it can be applied to future flexible electronics. 

Speaker
Biography:

Elham Shafik Aazam has completed her PhD from Sussex University, UK and is a Professor at King Abdulaziz University at the Science College and Chemistry department. She is the Head of the Chemistry department at the female campus. She has published 43 papers in reputed journals.

Abstract:

Natural biodegradable polymeric starch capped Ag-nanoparticles (AgNPs) were prepared by using extract of Dioscorea deltoidea in the presence of starch. UV-visible spectroscopy, transmission electron microscopy (TEM), X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), Fourier-transform infrared (FT-IR) spectroscopy, and digital images were used to determine the morphology and chemical composition of the as prepared AgNPs. The kinetics and morphology of the nano-materials (spherical, rod, triangular, irregular, truncated triangular, hexahedral, mono-ispersed, and aggregated) were discussed in terms of the extract, Ag+ and starch. Iodometric titration was used to confirm the reversible encapsulation of the AgNPs inside the helical structure of amylose. TEM images also suggest that the morphology of the encapsulated AgNPs entirely changes in comparison with the non-encapsulated AgNPs. The starch functionalized AgNPs could be used for drug delivery, with the nucleation and aggregation controlled through fusogenic behaviour.

Speaker
Biography:

Lucas C Grosche has completed his BSc in Chemical Engineering Chemistry at Oswaldo Cruz University, Brazil, and MSc in Chemical Engineering Chemistry at São Paulo University. Currently, he is pursuing his Ph.D. in Technology Materials at Nuclear and Energy Research Institute, Brazil.

Abstract:

Semi-dry flue gas desulfurization ash (SDA) is a byproduct generated from the desulfurization system of the coal-fired power station. The beneficial reuse application for SDA material is relatively undeveloped and this residue is underutilized. SDA was used as raw material for the synthesis of zeolitic material by alkaline hydrothermal treatment. Different experimental conditions, such as reaction time, temperature, alkali hydroxide concentration and solid/liquid ratio were studied. Raw ash material and synthesis products were characterized by XRD, XRF, particle size analyzer, TG-DTG-DTA and SDA were classified according to Brazilian Environmental Regulations. The results show that SDA has a higher CaO and SO3 content. The major minerals present in SDA are hannebachite, anhydrite, calcite, portlandite, gehlenite and sodium carbonate. The size of SDA particles is around 0.399-355.656 µM with a median diameter of 7.63 µM. Thermal behavior of SDA was characterized by the existence of six and four stages under air and inert atmosphere, respectively. SDA can be classified as Class II A (non-dangerous/non-inert) materials. The presence of zeolite hydroxysodalite confirms successful conversion of SDA into zeolitic material after activation in NaOH solutions. Along with the zeolitic product were obtained katoite, hydrocalumite, and Al-substituted tobermorite. All the compounds formed present ionic exchange capacity. SDA utilization minimizes the environmental impact of disposal problems and further enables an application for treatment of wastewater.

Speaker
Biography:

Lucas C Grosche has completed his BSc in Chemical Engineering Chemistry at Oswaldo Cruz University, Brazil, and MSc in Chemical Engineering Chemistry at São Paulo University. Currently, he is pursuing his Ph.D. in Technology Materials at Nuclear and Energy Research Institute, Brazil.

Abstract:

Semi-dry flue gas desulfurization ash (SDA) is a byproduct generated from the desulfurization system of the coal-fired power station. The beneficial reuse application for SDA material is relatively undeveloped and this residue is underutilized. SDA was used as raw material for the synthesis of zeolitic material by alkaline hydrothermal treatment. Different experimental conditions, such as reaction time, temperature, alkali hydroxide concentration and solid/liquid ratio were studied. Raw ash material and synthesis products were characterized by XRD, XRF, particle size analyzer, TG-DTG-DTA and SDA were classified according to Brazilian Environmental Regulations. The results show that SDA has a higher CaO and SO3 content. The major minerals present in SDA are hannebachite, anhydrite, calcite, portlandite, gehlenite and sodium carbonate. The size of SDA particles is around 0.399-355.656 µM with a median diameter of 7.63 µM. Thermal behavior of SDA was characterized by the existence of six and four stages under air and inert atmosphere, respectively. SDA can be classified as Class II A (non-dangerous/non-inert) materials. The presence of zeolite hydroxysodalite confirms successful conversion of SDA into zeolitic material after activation in NaOH solutions. Along with the zeolitic product were obtained katoite, hydrocalumite, and Al-substituted tobermorite. All the compounds formed present ionic exchange capacity. SDA utilization minimizes the environmental impact of disposal problems and further enables an application for treatment of wastewater.

Speaker
Biography:

Jianyong (Jerry) Wang received his Ph.D. from the Department of Biochemistry and Molecular Biology at Medical University of Ohio (Toledo, OH). After postdoctoral studies at University of Michigan Medical Center, Jerry began his industry career as a pharmacologist. He is currently a scientist in the Department of Biochemical and Cellular Pharmacology at Genentech. His group supports the therapeutic antibody programs during research and early development phases. His main responsibilities include antibody screening and characterization by in vitro and in vivo studies to select clinical candidates. Dr. Wang has worked in the biopharmaceutical industry for more than fifteen years including ten years at Genentech for biotherapeutics R&D.

Abstract:

As many of therapeutic biologics (including monoclonal antibodies and antibody-drug conjugates) enter the frontline of disease treatment, tracking their stability in vivo, is a critical step in development of these therapeutics. Unstable antibody therapeutics (including unstable antibody-drug conjugates) may cause decreased drug activity, fast clearance, increased immunogenicity, and safety issues (toxicities). Non enzyme mediated deamidation is a common protein degradation that normally occurs on asparagine (and to a lesser extent, glutamine residues), resulting in a conversion to aspartic and isoaspartic acids with a mass shift of +0.984 Da. To monitor the deamidation of therapeutic antibodies dosed in vivo, we developed analytical methods with the combination of immunoassay and LC/MS using peptide level MS detection. We further optimized the process and established an automated high throughput method allowing for high fidelity deamidation analysis of human antibodies from in vivo study samples. Similarly, we were also able to characterize the stability of antibody-drug conjugates in vivo, by using the combination of affinity-capture and intact protein MS analysis. These procedures will help to exclude unstable drug candidates at early development phase, and select stable antibody-based therapeutics for clinical applications.

Speaker
Biography:

He completed his Ph.D. at University of Cambridge, the UK in the year of 1980. He is working as Professor, American University of Beirut, Lebanon. His research interests are Membrane fusion in vitro, Plant cell wall biosynthesis, and assembly, Biologically active oligosaccharides.

Abstract:

Biotransformation is an efficient approach for structural alteration of all classes of organic compounds. This technique is effectively employed in green chemistry, particularly in drug discovery and development, as it involves a variety of enzymes during transformation which results in regio-, chemo-, and stereo-selective products. In the current study, biotransformation of an orally active contraceptive drugs, drospirenone and etonogestrel was carried out at pH 7.0 and 26±2°C. Transformation of drospirenone with Cunninghamella elegans resulted in four new metabolites, 14α-hydroxy-drospirenone, 11-oxo-drospirenone, 12-oxo-drospirenone and 11β, 14α-dihydroxy-drospirenone, along with a known metabolite and 11α-hydroxy-drospirenone. While transformation of etonogestrel with Cunninghamella blakesleeana and C. echinulata yielded three new metabolites 6β-hydroxy-11, 22-epoxy-etonogestrel, 11, 22-epoxy-etonogestrel, 10β-hydroxy-etonogestrel, along with two known metabolites 6β-hydroxy-etonogestrel, and 14α-hydroxy-etonogestrel.

Roya Rafiee

Post Doctoral Associate at University of Florida

Title: Small Molecules Approach for Conversion into the Neuronal Lineage

Time : 16:50-17:15

Speaker
Biography:

Roya Rafiee is a Post Doctoral Associate at University of Florida.

Abstract:

Over the past years, manipulation of cell identity to derive a desired organ specific cell type has become a major research interest since efficient reprogramming via forced expression of transcription factors had been achieved. The major aim of these studies is to obtain any somatic cell type that can be used in drug discovery and regenerative medicine, but genetic manipulation of cells by the use of tissue-specific transcription factors poses unknown risks and is therefore associated with safety concerns.

Recent work showed that trans differentiation can be also achieved with a gene-free approach using small,   chemically defined molecules. In my work presented here, it can be shown for the first time that human fibroblast cells can be converted into cells of the dopaminergic lineage with a cocktail of small molecules containing epigenetic modifiers targeting histone acetylation and histone methylation, kinase inhibitors, and a regulator of cAMP levels. The converted fibroblasts exhibit neuron specific gene expression pattern at the mRNA and protein level, and also produced dopamine indicating this fundamental functional property. A crucial part in the protocol is the inhibition of TGFβ, BMP and GSK3β signaling in order to convert fibroblast into the neurons, which could be modulate by the small molecule inhibitor E738. High levels of AKT1 and GSK3β phosphorylation in the absence of CREB activation indicated an important new cross talk between AKT1 and GSK3β signaling for the neuronal lineage. Activation of Chk2 and HSP27 did not differ significantly from non-induced fibroblast, confirming low toxicity of the cocktail used.

Induced fibroblasts did not exhibit a transient progenitor cells phase. On the other hand, postnatal mouse glia cells treated with a similar cocktail of small molecules as used for fibroblast trans differentiation, were converted into semi-functional neurons through a proliferative, “de-differentiated”, stage via adding the small molecules BIX. We observed that de-differentiated glia cells possessed neuronal stem cell like properties indicated by gene expression, self-renewal and neurerosphere generation properties, other neuronal specific markers and half Na+ channel current.

Taken together, the results presented here clearly show that using well defined combinations of small chemical molecules can be sufficient to obtain functional neurons of the dopaminergic lineage by reprogramming from human fibroblast. Moreover, with minor adjustments, a similar cocktail of small molecules was sufficient to obtain semi-functional neurons starting with postnatal glia cells without the introduction of exogenous genetic factors.

Biography:

Abstract:

liver fibrosis is the wound healing response to a variety of acute or chronic stimuli, for instance, viral infection, toxins, and metabolic diseases. The pattern of hepatic stellate cell activation provides an important framework to pinpoint sites of anti-fibrotic therapy. IFN exhibit a wide spectrum of biological activities in target cells including antiviral, immunomodulatory, anti angiogenic and growth-inhibitory effects. The antiproliferative effects of IFN are the rational basis for their use in the treatment of metastatic malignant melanoma and renal cell carcinoma. The food use of S.oleraceus is justified by the high content of vit.C, flavonoids, and phenolics. The previous studies discussed the antifibrotic effect of IFN and S.oleraceus individually on liver fibrosis but in this study, the combination treatment has been studied well in the induced liver fibrosis models. Using different immunoassays, Histopathology, colorimetric and PCR techniques the results obtained showed that TAA causes hepatic fibrosis by induction of free radical production and decrease cellular antioxidant stores. The different treatment ways including combination treatment group showed a significant inhibitory effect in targeting hepatic fibrosis by reducing oxidative stress, increasing the activity of antioxidant enzymes and by inhibiting HSCs inflammation, activation and proliferation through increasing the levels of anti-fibrotic co-transcription factor PPAR-γ and decrease the levels of the main HSCs fibrogenic cytokines TGFβ1 and PDGF-BB.

In conclusion, biochemical, molecular and histopathological findings demonstrated that the combination treatment improved the antifibrotic effect better than the individual one,  the prophylactic usage of  SE protected against hepatic fibrosis and  SE had no side effect.

Petr Čársky

J. Heyrovský Institute of Physical Chemistry, Czech Republic

Title: Theory in service of nanochemistry induced by electron impact

Time : 17:40-18:05

Speaker
Biography:

Petr ÄŒársky has completed his Ph.D. in 1968 from the Czechoslovak Academy of Sciences. He served two terms as the Director of Heyrovský Institute. Presently, he is continuing his work at Heyrovský Institute as a Senior Researcher. He has published more than 180 papers in reputed journals. He is a member of the International Academy of the Quantum Molecular Science and a WATOC board member and has been serving as an Editorial Board Member of several reputed journals.

Abstract:

The aim of this presentation is to show the recent progress in applications of quantum chemistry and theory of electron scattering to the needs of nanofabrication of chips by deposition of metallic structures on the surface. Over the past decade, a new method called Focused Electron Beam Induced Processing has gained increasing attention as a fast and versatile lithography with sub-5 nm features. However, the advantages of FEBID, such as high spatial resolution and accessibility, are currently overset by insufficient control of the purity and shape of the desired end product. If control of the process is to be improved, it is necessary to understand the parameters that dominate electron-induced chemistry. Here comes the help from the side of theory. We can calculate the cross sections for dissociative electron attachment, i.e., the probabilities of metal-ligand bond fission on electron impact, and consequently to predict suitable precursors and optimum electron energies.  The calculations are based on the ab inito treatment of the Lippmann-Schwinger equation for vibrationally inelastic scattering and a quantum-chemical approach for a direct evaluation of dissociative attachment by a local resonance model. Possible benefits for general quantum chemistry will also be noted: use of graphics processing units, use of hybrid Gaussian and plane-wave basis sets, and efficient evaluation of two-electron exchange integrals.

Speaker

Chair

Bruce M Novak

The University of Texas, USA

Speaker

Co-Chair

John George Hardy

Lancaster University, UK

Session Introduction

Mihaela C. Stefan

The University of Texas, USA

Title: Donor-acceptor polymers for organic photovoltaics

Time : 10:00-10:25

Speaker
Biography:

Mihaela C Stefan received her Ph.D. degree in Chemistry from Politehnica University Bucharest. She joined the Department of Chemistry at the University of Texas at Dallas in 2007 and was promoted to Associate Professor in 2013. She has received a joint appointment in the Bioengineering Department in 2014. She received the NSF Career Award in 2010, the NS&M Outstanding Teacher Award in 2009 and 2017, the Inclusive Teaching Diversity Award in 2012, President’s Teaching Excellence Award in 2014, and the Provost’s Award for Faculty Excellence in Undergraduate Research Mentoring in 2015. Her research group is developing novel polymeric materials for organic electronics and drug delivery applications.

Abstract:

Furan and its derivatives are promising alternative building blocks for the synthesis of semiconducting polymers due to their properties such as smaller heteroatom size, a more electronegative heteroatom, and larger dipole moment. Conjugated polymers synthesized from furan show a higher degree of conjugation with reduced twisting between adjacent units, smaller π-stacking distance, and improved solubility in organic solvents. Despite research on polymers constructed from furan derivatives gaining attention, conjugated polymers from furan only are still scarce. We reported a conjugated polymer, poly(4,8-bis(5-(2-ethylhexyl)furan-2-yl)benzo[1,2-b:4,5-b']difuran-alt-2,5-didodecyl-3,6-di(furan -2-yl)pyrrolo[3,4-c]pyrrole-1,4(2H,5H)-dione), P(BDF-FDPP), for organic solar cells. The smaller oxygen atom in furan of P(BDF-FDPP) resulted in a planar conjugated backbone with negligible torsion (dihedral angle < 0.10) determined by density functional theory. P(BDF-FDPP) exhibited broad absorption up to 940 nm with HOMO and LUMO located at -5.19 eV and -3.63 eV, respectively. Power conversion efficiency (PCE) of 5.55% with a high fill factor (FF) of 0.73 was measured for the devices fabricated using diphenyl ether (DPE) as an additive. The considerable change in photovoltaic performance of the devices fabricated with or without additives was investigated with grazing incident wide-angle X-ray scattering, and transmission electron microscopy experiments. The preferential face-on orientation of P(BDF-FDPP) and sophisticated interpenetrated network for P(BDF-FDPP)/PC71BM blend films enabled relatively good PCEs and high FF in solar cell devices.

Speaker
Biography:

John Hardy undertook his undergraduate and doctoral studies chemistry in Bristol and York in the UK. Thereafter he undertook 10 years of interdisciplinary postdoctoral research (in Pharmacy, Biomedical/Chemical Engineering and  Materials Science ) in France, Germany, Northern Ireland and the USA before returning to the UK for a 50th Anniversary lectureship in materials chemistry at Lancaster University. He has received a variety of awards from charities, governmental bodies and industry, and serves on the editorial board of a number of journals including Future Science OA and the International Journal of Molecular Sciences.

Abstract:

Stimuli-responsive instructive biomaterials are particularly attractive for the treatment of a variety of conditions either via the controlled delivery of precise quantities of drugs at specific locations and times, or indeed delivery of a cue (e.g. chemical, electrical, light, mechanical, topographical) to the cells interacting with the material (e.g. in the form of a medical device or tissue scaffold).

Materials responding to stimuli such as enzymes, light, pH, temperature, ultrasound and electric/magnetic fields have been developed for use as drug delivery devices, medical devices and tissue scaffolds. An interesting research area is the development of materials capable of controlling either cell behavior or the delivery of drugs in response to electricity, light and magnetism.

Here we report the development of polymer-based materials that enable the delivery of drugs in response to electrical fields, light and magnetism; the tuneable properties of the materials make them attractive components of electroactive/photoresponsive biomaterials that when non-degradable have potential application for long term medical devices (e.g. bioactive coatings, electrodes, tools), and when degradable have potential application for short term applications (e.g. drug delivery or tissue engineering). An overview of these developments will be presented.

Speaker
Biography:

Melikhan Tanyeri has received his PhD in Physics from University of California, Davis, where he developed chemical and biological sensor platforms based on optical resonances in microcavities. He has moved to University of Illinois at Urbana-Champaign for his Postdoctoral training, where he has developed a new class of microfluidic tools for trapping and manipulating micro and nanoscale particles. During 2013-2016, he was an Assistant Professor in the Department of Electrical Engineering at Istanbul Sehir University in Turkey, where his group was pursuing research at the interface of applied Physics, Engineering and Medical Sciences. He is currently working as a Research Scientist at the Institute of Molecular Engineering at the University of Chicago, developing tools for single cell analysis towards applications in Immunology. His research interests include optical biosensors, imaging and spectroscopy, molecular and cellular biophysics, microfluidics and bioMEMS.

Abstract:

We present a novel flow-based method to study the dissolution of individual microdroplets in aqueous solutions. For most two-phase systems, liquid-liquid miscibility is characterized by a small and often negligible quantity, thereby leading to the assumption that many emulsion systems are immiscible. Similarly, during emulsion generation, vast quantities of aqueous microdroplets are produced in host oil-based solutions and are considered stable for long periods of time. A careful study of oil-water miscibility at the micro scale will provide valuable insight into these systems. In this work, we report a new method enabling quantitative analysis of dissolution of an individual microdroplet in the immiscible medium. We observed that micro droplets, normally immiscible in host medium, dissolve substantially under planar extensional flow conditions. Furthermore, we developed a model accurately capturing the dissolution dynamics of individual droplets in the immiscible medium. We observed dissolution of individual oil micro droplets in aqueous solutions under planar extensional flow. Specifically, we confined single microdroplets at the stagnation point of a planar extensional flow generated at the junction of two perpendicular microchannels. We quantitatively analyzed micro droplet dissolution by acquiring consecutive images of a hydrodynamically-trapped microdroplet, and by measuring the change in average droplet diameter as a function of time. We demonstrated that dissolution of the oil phase in host aqueous solution could be substantial under laminar flow. In the absence of flow, the size of the oil microdroplets does not significantly change over a long period of time, as expected. We developed a model to explain flow-enhanced dissolution of micro droplets under planar extensional flow. This study demonstrates flow-induced dissolution of immiscible fluid-fluid systems at the micro scale and shows that the dynamics of dissolution can be predicted accurately by a numerical model. This novel method will enable fast and precise measurement of solubility and diffusion coefficients for immiscible two-phase (liquid-liquid and gas-liquid) fluid systems with potential applications towards food, cosmetic and pharmaceutical industries.

Speaker
Biography:

Yixin Ren is a McNair scholar. He received his BS degree in Chemistry & Medicinal Chemistry from the University at Buffalo in 2012. He subsequently completed his M.S. degree in chemistry from the Illinois State University in 2014 under the supervision of Lisa F. Szczepura. He is currently working on his Ph.D. in chemistry at the University of Texas at Dallas under supervision of Mihaela C. Stefan. His current research endeavors are focused on neodymium-based catalysts for polymerization of dienes and vinyl monomers and ring opening polymerization of cyclic esters.

Abstract:

Neodymium-based catalysts bearing phosphate ligands NdCl3·3L (L = triethyl phosphate (TEP) or tris(2-ethylhexyl) phosphate (TEHP) were successfully synthesized. The ring opening polymerization (ROP) of ε-caprolactone (ε-CL) initiated with these catalysts in the presence of a series of alcohols were performed yielding polymers with the narrow polydispersity index (PDI = 1.22 to 1.55) and controllable molecular weight. An important result from the kinetic studies revealed that the sterically bulkier ligand TEHP, as compared to TEP ligand significantly increased the rate for ROP of ε-CL. Di-block copolymers poly(ε-CL)-block-poly(D,L-lactide) via sequential monomer addition were successfully synthesized demonstrating the living nature of the catalytic system. 

Speaker
Biography:

Celyna K Rackov has completed her PhD degree in Chemical Engineering at the University of Sao Paulo (USP-Brazil) in 2014, in Environmental Technologies, with a scholarship from a Brazilian Program. Meanwhile, she has participated in a Doctorate fellowship at the University of Texas at Arlington. Between December 2015 to May 2016, she has worked as Postdoctoral researcher at USP in environmental area. She is remotely advising students from Chemical Engineering Department of the Federal University of Rio Grande do Norte, Brazil. From October to December 2016, she was teaching Chemistry classes in the Natural Sciences Department of the Dickinson State University (DSU - North Dakota, USA), as a special Faculty appointment. Since January 2017, she is working as Faculty in Chemistry at El Centro College, Dallas - TX.

 

Abstract:

Emerging pollutants have been subject of a worldwide study because they present a potential threat to the environment and human health, because of their continuous entry into the environment. In this context, researches are being developed with the aim of improving the methods for these pollutants elimination or reduction. Through the Advanced Oxidative Process (AOP) radicals are generated to oxidize the chemicals present in effluents. Thus, this work focuses on the treatment of the synthetic hormone 17α-ethinylestradiol in aqueous systems, using traditional methods: activating the oxidant through pH, temperature and iron ions compared to the innovative method that activated the persulfate by the catalyst (Modified Diatomite). According to the results, it can be concluded that the innovative activation method, using modified diatomite, was more efficient than the traditional methods, achieving a 98% removal of EE2 in 90 minutes of reaction.

Speaker
Biography:

Beena Jose has completed her Ph.D. in Chemistry from the University of Calicut in 2005. She has published 36 papers in various reputed national and international journals and authored one book. Her area of specialization is Natural Products Chemistry. Currently, she is working as an Assistant Professor in Chemistry, Vimala College, Thrissur, Kerala, India. She has presented papers in India and abroad. As a part of International Fellowship Program, she has been selected as an International Visiting Research Scholar at the Jesuit School of Theology (JST) of Santa Clara University, the USA for the year 2014-15. She is the recipient of University Grants Commission’s (UGC) Major and Minor research projects. Her area of interests are phytochemical analysis and structural elucidation of the compounds isolated from plants.

Abstract:

Wrightia tinctoria R. Br. belongs to family Apocynaceae commonly called as “Jaundice curative tree” in South India. In Siddha system of medicine, it is used for psoriasis and other skin diseases. In the present study various secondary metabolites from the leaf and bark of Wrightia tinctoria (Pala Indigo) were isolated by column chromatography and characterized by spectral analysis (1H NMR, 13C NMR, IR, Mass Spectrum). The antibacterial and antifungal activities of the plant extracts against various pathogenic bacteria such as Bacillus cereus, Enterobacter faecalis, Salmonella paratyphi, Staphylococcus aureus, Escherichia coli, Proteus vulgaris, Klebsiella pneumoniae, Pseudomonas aeruginosa and Serratia marcescens and antifungal activity against two fungi namely Aspergillus niger and Penicillium chrysogenum were evaluated by agar well diffusion method. The anticancer potential of Wrightia tinctoria was studied both in vitro and in vivo. Anti-tumor properties of Wrightia tinctoria could be linked with the presence of antioxidants and cytotoxic activity. These outcomes indicate the possible potential use of Wrightia tinctoria as anti-tumor agent.

Biography:

Abstract:

 Double layered one-by-one imprinted hollow core-shells@ pencil graphite electrode was fabricated for sequential sensing of anti-HIV drugs. For this, two eccentric layers were developed on the surface of vinylated silica nanospheres to obtain double layered one-by-one imprinted solid core-shells, which on treatment with hydrofluoric acid yielded hollow core-shells. Whereas modified hollow core-shells (single layered dual imprinted) evolved competitive diffusion of probe/analyte molecules, the corresponding double layered one-by-one imprinted hollow core-shells (outer layer imprinted with Zidovudine, and inner layer with Lamivudine) were found relatively better owing to their bilateral diffusions into molecular cavities without any competition. Therefore, entire work in this article is based on differential pulse anodic stripping voltammetry at double layered one-by-one imprinted hollow core-shells, which imparted indirect detection of electro inactive targets with limits of detection as low as 0.91 and 0.12 (aqueous sample), 0.94 and 0.13 (blood serum), and 0.99 and 0.20 ng mL-1 (pharmaceutics) for lamivudine and zidovudine, respectively in anti-HIV drug combination. 

Biography:

Abstract:

The pharmaceutical demand for plant-based colchicine is increasing because it is an effective FDA-approved gout medicine that also has potential for cancer therapeutics due to its ability to bind to microtubules and halt cell division. Understanding the biorhizome developmental genes are necessary to improve the biomanufacturing of colchicine. RNA-Seq was used to identify the rhizome developmental genes from Gloriosa superba and Colchicum autumnale. The transcriptome of both species were compared against NCBI and Swissprot protein databases. Python scripts were utilized to parse the transcriptome. Bioinformatics analysis revealed 60927 assembled multiple-tissue transcripts of C. autumnale represented 21948 unigenes and G. superba has 32312, which represented 15089 unigenes in known plant specific gene ontology (GO). Further GO analysis was used to identify known rhizome-specific and developmental genes in G. superba. This study could provide a foundation to enhance the biorhizome-based colchicine biomanufacturing in G. superba

Biography:

Abstract:

Colchicine is a FDA-approved plant-based alkaloid that is commonly used to treat gout. It has also been proven to be beneficial in cardiovascular diseases and its antimitotic properties make it a promising cancer treatment. Traditionally, the natural isomer of colchicine is exacted from Gloriosa superba, which was initially isolated from Colchicum autumnale. The biosynthetic pathway of colchicine is not yet characterized, and the pathway genes and mechanisms must be elucidated to improve colchicine production.  G. superba and C. autumnale transcriptomes were analyzed and compared against NCBI and Swissprot protein databases to identify the biosynthetic pathway genes. The annotation data of these transcriptomes revealed that there were 60927 assembled multi-tissue transcripts of C. autumnale, which represented 21945 unigenes. Additionally, G. superba has 32312 assembled multi-tissue transcripts which represented 15088 unigenes in known plant-specific Gene Ontology (GO). Gene annotation and pathway mapping data will be presented. 

Biography:

Abstract:

Gloriosa superba is a commercial source of the pharmaceutical colchicine. Colchicine is one of the primary sources of treatment for gout. The balloon type bubble reactor (BTBR) has been successfully used to biomanufacture bioactive small molecules. Colchicine production can be improved by understanding the fluid mechanics inside this reactor, which primarily depends on several parameters such as reactor working volumes, diameter of the sparger, flow rate, viscosity, surface tension, density of the fluids, and nutrient volume fractions. Our initial bioimaging study suggests that in 4L BTBR at low air injection rate the flow ascends up a fairly straight vertical path, concentrating mostly toward the center of the reactor. However, at higher injection rates, a more chaotic flow forms. The post processed images reveal that the flow patterns inside the reactor vary, as positive and negative vorticity zones. We will present the clockwise/counter-clockwise directions of the dimensionless mapping of fluid dynamics data. This analysis will not only address the geometric patterns of mixing, but will also apply to the nature of liquids, solutions, and injection gases with various combinations of density, viscosity, and surface tension that will eventually improve the colchicine biomanufacturing design process. 

Biography:

Xuyi Cai has his expertise in Groundwater Chemistry and Atmospheric Chemistry. His research is involved in aerosol thermodynamics, secondary organic aerosol formation from biogenic and authropogenic volatile organic compounds, groundwater pollution in north China, and geochemical modelling. He has published his papers in several journals.

Abstract:

Statement of the Problem: Riparian vegetated buffer strips (RVBS) are widely constructed in the world to reduce the nutrient flux in surface runoff into surface water bodies to curb the development of eutrophication. However, which kinds of vegetation composition may reduce the nutrient flux in surface runoff more effectively is still an open problem. The purpose of this study is to determine whether plant species significantly influences its floor soil denitrification potentials for a planted forest.

Methodology & Theoretical Orientation: Two planted forests with different compositions in similar soil conditions in Zhushan Bay, in the buffer zone of Taihu Lake were chosen as the vegetation buffer strips for the comparison of their soil denitrification potentials. One is a composite forest composed of poplar trees, shrubs and herbs, named the poplar and shrub forest (PSF), and the other is composed of poplar and herbaceous plants, named the poplar forest (PF). Their floor surface runoff, the soil water and groundwater below their floor were monitored for one-year, and their soil denitrification potentials were compared. Laboratory DOC (dissolved organic carbon) leaching experiments of plant leaf and root were conducted which occurs in the study area.

Findings: The research results show that: There is a maximum value for the measured denitrification potentials around the depth of 40 cm in the vertical soil profiles for both planted forests, coincided with lower values for DO concentration and Eh at the same depth, proving the existence of a coupled nitrification-denitrification layer; in the vertical soil profiles for both planted forests, all the maximum values for the soil denitrification potentials and the numbers of denitrification bacteria in these two forests occur around the depth of 40 cm, demonstrating the existence of an active denitrification layer (composed of biogeochemical hot-spots) around the depth of 40 cm, which is closely related to the root system of grass vegetation for both forests; at the same depth, the soil denitrification potentials for PSF are twice of those for PF, however, there is no significant difference for the actual denitrification rates for the soils in both forests, which are limited by the concentration of nitrate in soil water and plant species have important influence on soil denitrification potentials.

Conclusion & Significance: Vegetation composition is an important influence factor for RVBS systems to remove nitrate in surface runoff and groundwater.