Chemistry Commons^™

The Development Of An Electrochemistry Experiment For Analytical Chemistry, Kaitlin Hickman

2024 Student Academic Showcase

The analytical chemistry course at Lindenwood University discusses the use of electrochemistry as part of the course curriculum. Much of the course content has practical lab experiments that teach the students the skills that they need if they enter the workforce as analytical chemists. The current lab curriculum does not have an experiment in electrochemistry. Dr. Delgado and Ms. Hickman are working on the redesign of an experiment that was intended for a physical chemistry class as a new lab that uses available technology and analytical techniques that can be written for the use in future semesters of the analytical …

Unlocking The Secret To Weight Loss: Discovering The Most Effective Green Tea Products, Seoyeon Kim

SACAD: John Heinrichs Scholarly and Creative Activity Days

To find the most effective green tea product that can replace

weight loss drugs, we compared the amount of catechin in six

different green tea products. The result was green tea latte

powder contained a significantly small amount of catechin

compared to other products, and the dried pearl green tea leaves

had the highest amount of catechin. Also, the unexpected result

was that green tea supplements had less amount of catechin

compared to dried leaves or even tea bags that are commonly

sold in markets.

Extraction Of Sandalwood Essential Oil: Isolating Α/Β-Santalol, Maeren Horton

Dr. Jay W. Boland Undergraduate Research Symposium

Sandalwood oil is a high-value essential oil extracted from the heartwood of East Indian Sandalwood (Santalum album) and Australian Sandalwood (Santalum Spicatum) and is prominent in numerous luxury perfume brands due to its exotic, versatile, and pleasant fragrance. α-Santalol, the main aromatic constituent in S. album and S. spicatum, exhibits anti-aging, antioxidant, anti-inflammatory, and potential anti-cancer properties, accounting for the oil’s medicinal and dermatologic applications. High demand of the oil resulted in excessive harvesting of sandalwood trees, necessitating a need to develop more efficient and sustainable extraction methods. This study investigates the efficiency of traditional extraction methods of sandalwood oil …

Structural, Spectroscopic, And Computational Insights From Canavanine-Bound And Two Catalytically Compromised Variants Of The Ethylene-Forming Enzyme, Shramana Chatterjee, Matthias Fellner, Joel A. Rankin, Midhun George Thomas, Simahudeen Bathir Jaber Sathik Rifayee, Christo Christov, Jian Hu, Robert P. Hausinger

Michigan Tech Publications, Part 2

The ethylene-forming enzyme (EFE) is an Fe(II), 2-oxoglutarate (2OG), and l-arginine (l-Arg)-dependent oxygenase that either forms ethylene and three CO2/bicarbonate from 2OG or couples the decarboxylation of 2OG to C5 hydroxylation of l-Arg. l-Arg binds with C5 toward the metal center, causing 2OG to change from monodentate to chelate metal interaction and OD1 to OD2 switch of D191 metal coordination. We applied anaerobic UV-visible spectroscopy, X-ray crystallography, and computational approaches to three EFE systems with high-resolution structures. The ineffective l-Arg analogue l-canavanine binds to the EFE with O5 pointing away from the metal center while promoting chelate formation by 2OG …

Advanced Electroanalysis For Electrosynthesis, Monica Brachi, Wassim El Housseini, Kevin Beaver, Rohit Jadhav, Ashwini Dantanarayana, Dylan G. Boucher, Shelley D. Minteer

Chemistry Faculty Research & Creative Works

Electrosynthesis is a Popular, Environmentally Friendly Substitute for Conventional Organic Methods. It Involves using Charge Transfer to Stimulate Chemical Reactions through the Application of a Potential or Current between Two Electrodes. in Addition to Electrode Materials and the Type of Reactor Employed, the Strategies for Controlling Potential and Current Have an Impact on the Yields, Product Distribution, and Reaction Mechanism. in This Review, Recent Advances Related to Electroanalysis Applied in Electrosynthesis Were Discussed. the First Part of This Study Acts as a Guide that Emphasizes the Foundations of Electrosynthesis. These Essentials Include Instrumentation, Electrode Selection, Cell Design, and Electrosynthesis Methodologies. …

Chiral Recognition Of Chiral (Hetero)Cyclic Derivatives Probed By Tetraaza Macrocyclic Chiral Solvating Agents Via ¹H Nmr Spectroscopy, Yu Wang, Hongmei Zhao, Chunxia Yang, Lixia Fang, Li Zheng, Hehua Lv, Pericles Stavropoulos, Lin Ai, Jiaxin Zhang

Chemistry Faculty Research & Creative Works

In the Field of Chiral Recognition, Chiral Cyclic Organic Compounds, Especially Heterocyclic Organic Compounds, Have Attracted Little Attention and Have Been Rarely Studied as Chiral Substrates by Means of 1H NMR Spectroscopy. in This Paper, Enantiomers of Thiohydantoin Derivatives, Representing Typical Five-Membered N,N-Heterocycles, Have Been Synthesized and Utilized for Assignment of Absolute Configuration and Analysis of Enantiomeric Excess. All Enantiomers Have Been Successfully Differentiated with the Assistance of Novel Tetraaza Macrocyclic Chiral Solvating Agents (TAMCSAs) by 1H NMR Spectroscopy. Surprisingly, Unprecedented Nonequivalent Chemical Shift Values (Up to 2.052 Ppm) of the NH Proton of Substrates Have Been Observed, a New …

Impact Of Pulsed Electric Field Treatment On Barley Germination For Malting, Rose Saxton, Caitlin Lahey, Brianna Smith, Emily Hibberd, Joshua Bevan, Cini Baumhoff, Ashley Galant, Jerry Young, Brian Meyer, Owen M. Mcdougal

Chemistry and Biochemistry Faculty Publications and Presentations

The malting process takes one week to steep, germinate, and kiln barley to make malt. Making quality malt is critically important to achieve the desired attributes of the finished beer, and the process is time-intensive and costly. Malt quality is assessed by indicators including β-glucan quantity, α-amylase activity, Free Amino Nitrogen (FAN) content, and overall extract concentration in the finished malt. Here, we report Pulsed Electric Field (PEF) treatment of barley to accelerate malt production. A small-scale trial of 250 g to 1.00 kg barley, was evaluated for germination at two PEF treatment conditions, generically referred to as “low” and …

Synthesis Of An Anti-Lysozyme Antibody Tagged With Gold Or Silver Nanoparticle For Faster Western Blot, Harunobu Kato

Chemistry Senior Theses

Western blot is an important protein analysis assay enabling protein detection by visualizing the antibody specific antigen-antibody interaction. As a commonly used assay, western blot is taught in upper-level biochemistry and molecular biology students. However, due to its exhaustive process and high cost of antibodies, a modification to western blot is proposed using gold or silver nanoparticles as a tag to the primary antibody for lysozyme. In this experiment, invisible anti-lysozyme antibodies were conjugated to colloidal gold and silver nanoparticles via photochemical immobilization technique, effectively facilitating a physically observable band on the western blot. To eliminate false positives by interactions …

Structure, Dynamics, And Redox Reactivity Of An All-Purpose Flavodoxin, Sharique Khan, Ahmadullah Ansari, Monica Brachi, Debarati Das, Wassim El Housseini, Shelley Minteer, Anne Frances Miller

Chemistry Faculty Research & Creative Works

The Flavodoxin Of Rhodopseudomonas Palustris CGA009 (Rp9Fld) Supplies Highly Reducing Equivalents To Crucial Enzymes Such As Hydrogenase, Especially When The Organism Is Iron-Restricted. By Acquiring Those Electrons From Photodriven Electron Flow Via The Bifurcating Electron Transfer Flavoprotein, Rp9Fld Provides Solar Power To Vital Metabolic Processes. To Understand Rp9Fld's Ability To Work With Diverse Partners, We Solved Its Crystal Structure. We Observed The Canonical Flavodoxin (Fld) Fold And Features Common To Other Long-Chain Flds But Not All The Surface Loops Thought To Recognize Partner Proteins. Moreover, Some Of The Loops Display Alternative Structures And Dynamics. To Advance Studies Of Protein–protein Associations …

Finding The Perfect Purple: An Exploration Of Glaze Making And Chemical Safety In The Pottery Studio, Kara Eppard, Michael Hough

ASPIRE 2024

This project was undertaken as an IDS-100H course linkage between ceramics and chemistry. Through time spent reviewing literature and time in the studio, a project was developed that allowed the application of technical skills of each discipline in a creative fashion. The creative focus of the project was to find a suitable purple glaze to utilize on a previously thrown pottery collection. During the project techniques in glaze making were explored. Over 25 glazes were tested, and two firing techniques were explored. Additionally, safety within the pottery studio was increased through aspects such as the development of an MSDS, and …

Comparison Of Emissions Across Tobacco Products: A Slippery Slope In Tobacco Control, Ahmad El-Hellani, Ayomipo Adeniji, Hanno C. Erythropel, Thomas Lamb, Qixin Wang, Vladimir Mikheev, Robert Strongin, Multiple Additional Authors

Chemistry Faculty Publications and Presentations

In this narrative review, we highlight the challenges of comparing emissions from different tobacco products under controlled laboratory settings (using smoking/ vaping machines). We focus on tobacco products that generate inhalable smoke or aerosol, such as cigarettes, cigars, hookah, electronic cigarettes, and heated tobacco products. We discuss challenges associated with sample generation including variability of smoking/vaping machines, lack of standardized adaptors that connect smoking/vaping machines to different tobacco products, puffing protocols that are not representative of actual use, and sample generation session length (minutes or number of puffs) that depends on product characteristics. We also discuss the challenges of physically …

Accurate Characterization Of Binding Kinetics And Allosteric Mechanisms For The Hsp90 Chaperone Inhibitors Using Ai-Augmented Integrative Biophysical Studies, Chao Xu, Xianglei Zhang, Lianghao Zhao, Gennady M. Verkhivker, Fang Bai

Mathematics, Physics, and Computer Science Faculty Articles and Research

The binding kinetics of drugs to their targets are gradually being recognized as a crucial indicator of the efficacy of drugs in vivo, leading to the development of various computational methods for predicting the binding kinetics in recent years. However, compared with the prediction of binding affinity, the underlying structure and dynamic determinants of binding kinetics are more complicated. Efficient and accurate methods for predicting binding kinetics are still lacking. In this study, quantitative structure–kinetics relationship (QSKR) models were developed using 132 inhibitors targeting the ATP binding domain of heat shock protein 90α (HSP90α) to predict the dissociation rate …

Spectroscopy Of Atmospheres, Randika Dodangodage

Physics Theses & Dissertations

Spectroscopic methods are used to study planetary and stellar atmospheres. The information obtained from spectroscopic studies provides insight into atmospheric compositions and dynamics, which can be used to model and characterize atmospheres and climates. Laboratory-recorded absorption cross-sections are needed to interpret the recorded spectra of planets and stars. High resolution ethane, neopentane, propene, and n-butane spectra have been recorded, and absorption cross-sections have been provided for different temperatures and total pressures with different broadening gases, including hydrogen, helium, and nitrogen. The Atmospheric Chemistry Experiment (ACE) satellite orbits Earth and records spectra through solar occultation limb observations. HOCl is a chlorine …

Broadband Dielectric Spectroscopic Detection Of Volatile Organic Compounds With Zinc Oxide And Metal-Organic Frameworks As Solid-State Sensor Materials, Papa Kojo Amoah

Electrical & Computer Engineering Theses & Dissertations

The industrial revolution drove technological progress but also increased the release of harmful pollutants, posing significant risks to human health and the environment. Volatile organic compounds (VOCs), which have various anthropogenic and natural sources, are particularly concerning due to their impact on public health, especially in urban areas. Addressing these adverse effects requires comprehensive strategies for mitigation as traditional gas sensing techniques have limitations and there is a need for innovative approaches to VOC detection.

VOCs encompass a diverse group of chemicals with high volatility, emitted from various human activities and natural sources. These compounds play a crucial role in …

Exploring Cation Exchange: Unveiling Its Significance In Biochar And Bioenergetics Applications, Gyanendra Kharel

Chemistry & Biochemistry Theses & Dissertations

Cation exchange, a cornerstone of soil chemistry and nutrient cycling, is a fundamental chemical process that occurs in soils, sediments, membranes, and other solid materials. It involves the interchange of positively charged ions, or cations, between a solid matrix and a surrounding solution. This process is crucial in various natural and engineered systems, leading to a range of applications across different fields.

This dissertation presents an extensive investigation into the applications of cation exchange in the fields of biochar and bioenergetics, encompassing three distinct aims. The first aim concentrates on the surface oxygenation of biochar through ozonization, aiming to achieve …

Analyzing The Influence Of Design And Operating Conditions On Combustion And Emissions In Premixed Turbulent Flames: A Comprehensive Review, Medhat Elkelawy Prof. Dr. Eng., E. A. El Shenawy Prof. Dr., Hagar Alm-Eldin Bastawissi, Ibrahim Ali Mousa Eng., Mohamed M. Abdel-Raouf Ibrahim Dr. Eng.

Journal of Engineering Research

Recently, premixed combustion has dominated the field of combustion research worldwide. The current work is a review that addresses the effects of design and operating regimes on the combustion and emission characteristics of premixed turbulent flames. The study accounts for recent developments aimed at overcoming combustor operability issues that influence emissions and flame stability. Various experimental setups have been utilized in investigations, with results pertaining to performance and emissions concerning premixed turbulent flames. Thus, the objective of this paper is to provide a comprehensive review of the effects of swirl vane angles and equivalence fuel-air ratios for tests conducted both …

Accurate Estimation Of Ethanol Content In Fruit Juices Using Cielab Color Space And Chemometrics Via Smartphone-Based Digital Image Colorimetry, Chairul Ichsan, Yasir Amrulloh, Desti Erviana

Makara Journal of Science

This study aims to investigate the optimal color space and chemometric technique for digital image colorimetry to determine ethanol content (% v/v) in apple, orange, and grape juices, using potassium dichromate (K₂Cr₂O₇) under acidic conditions. The accuracy of colorimetric–chemometric integration across various color spaces (RGB, HSV, CIELab, CMYK, CIELuv, CIEXYZ, and CIELch) was benchmarked against UV–Vis spectrophotometry using metrics such as coefficient of determination (R²), mean absolute percentage error (MAPE), and root–mean–squared error (RMSE). Various chemometric techniques (PLS, PCR, MLR, multivariable–SVR, and multivariable NN regression) were evaluated. Results demonstrate that combining the CIELab color …

Synthesis, Molecular Characteristics, And Antibacterial Assessment Of Marine Hydroid Aqueous Extract-Based Silver Bio-Nanoparticles, Fredryk Mandey, Aulia Rhamdani Arfan, Rugaiyah Andi Arfah

Makara Journal of Science

This investigation aims to synthesize, analyze the molecularity, and test the ability of bacterial inhibition capability of silver nanoparticles that have been synthesized by simply mixing silver nitrate and aqueous extracts of marine natural products with and without the addition of amylum as a stabilizing agent. This research, with and without the addition of amylum as a stabilizing agent, obtained 39.0 and 55.2 mg of solids of round-shaped morphology silver nanoparticles with diameters of 87.9 and 103.0 nm., respectively. In addition, the antibacterial testing assay against Staphylococcus aureus and Escherichia coli showed some considerably good results. S. aureus with the …

Advancements In Characterization Of Ancient Potteries From Southeast Asia: A Review Of Analytical Techniques, Chitnarong Sirisathitkul

Makara Journal of Science

Ancient potteries offer valuable information regarding technological advancements, life dynamics, cultural diversity, and trade routes in the past. Earthenware, stoneware, and porcelain from Southeast Asia have been characterized using several analytical techniques, as reviewed in this article. Fluorescent and diffracted X-rays give rise to elemental and phase compositions, respectively. Examination of molecular bonds requires vibrational spectroscopy, which is useful for the identification of organic materials in ancient potteries. With the advent of portable X-ray fluorescence and Raman spectrometry, on-site analysis of archeological ceramics is now possible. For in-depth analysis, synchrotron light sources can provide new insights into artifacts through X-ray …

Micropatterning And Functionalization Of Single Layer Graphene: Tuning Its Electron Transport Properties, Miao-Miao Cui, Lian-Huan Han, Lan-Ping Zeng, Jia-Yao Guo, Wei-Ying Song, Chuan Liu, Yuan-Fei Wu, Shi-Yi Luo, Yun-Hua Liu, Dong-Ping Zhan

Journal of Electrochemistry

As a promising 2D material, graphene exhibits excellent physical properties including single-atom-scale thickness and remarkably high charge carrier mobility. However, its semi-metallic nature with a zero bandgap poses challenges for its application in high-performance field-effect transistors (FETs). In order to overcome these limitations, various approaches have been explored to modulate graphene's bandgap, including nanoscale confinement, external field induction, doping, and chemical micropatterning. Nevertheless, the stability and controllability still need to be improved. In this study, we propose a feasible method that combines electrochemical bromination and photolithography to precisely tune the electron transport properties of single layer graphene (SLG). Through this …

The Determination Of Pzc And Differential Capacitance Curve Of Platinum-Alkaline Polymer Electrolyte Interfaces, Chen-Xi Liu, Ze-Ping Zou, Mei-Xue Hu, Yu Ding, Yu Gu, Shuai Liu, Wen-Jing Nan, Yi-Chang Ma, Zhao-Bin Chen, Dong-Ping Zhan, Qiu-Gen Zhang, Lin Zhuang, Jia-Wei Yan, Bing-Wei Mao

Journal of Electrochemistry

Alkaline polymer electrolyte (APE) is the core component of modern alkaline hydrogen and oxygen fuel cells, and its single ion conductor nature makes the "electrode/APE" interfaces different from the conventional "electrode/solution" interfaces in terms of ion distribution, electrical double layer structure and polarization behavior. Due to the complexity of the APE and the associated solid-solid interfaces, fundamental investigations are challenging and deeper understanding of the structures and properties of such interfaces is in the infant stage. In this work, we aim to investigate the double layer structure from the aspects of differential capacitance curve and potential of zero charge (PZC) …

Recent Advances In Solar Photo(Electro)Catalytic Nitrogen Fixation, Jun-Bo Ma, Sheng Lin, Zhiqun Lin, Lan Sun, Chang-Jian Lin

Journal of Electrochemistry

Ammonia (NH₃) is an essential chemical in modern society. It is currently produced in industry by the Haber-Bosch process using H₂ and N₂ as reactants in the presence of iron-based catalysts at high-temperature (400–600 ^oC) and extremely highpressure (20–40 MPa) conditions. However, its efficiency is limited to 10% to 15%. At the same time, a large amount of energy is consumed, and CO₂ emission is inevitably. The development of a sustainable, clean, and environmentally friendly energy system represents a key strategy to address energy crisis and environmental pollution, ultimately aiming to achieve carbon neutrality. …

Dynamic Fibrillar Assembly Of Αb-Crystallin Induced By Perturbation Of The Conserved Nt-Ixi Motif Resolved By Cryo-Em, Russell Mcfarland, Steve Reichow

Chemistry Faculty Publications and Presentations

αB-crystallin is an archetypical member of the small heat-shock proteins (sHSPs) vital for cellular proteostasis and mitigating protein misfolding diseases. Gaining insights into the principles defining their molecular organization and chaperone function have been hindered by intrinsic dynamic properties and limited high-resolution structural analysis. To disentangle the mechanistic underpinnings of these dynamical properties, we mutated a conserved IXI-motif located within the N-terminal (NT) domain of human αB-crystallin. This resulted in a profound structural transformation, from highly polydispersed caged-like native assemblies into a comparatively well-ordered helical fibril state amenable to high-resolution cryo-EM analysis. The reversible nature of the induced fibrils facilitated …

Commemorating Women Nobel Prize Laureates In Chemistry, Jordan Smith

Arkansas Women in STEM Conference

In this review study we describe contributions of women chemists who earned a Nobel Prize in Chemistry, notably the most prestigious award in the field. Based on our analysis of data, the number of women Nobel laureates in Chemistry is increasing with time. However, women still are the minority group compared to men in a pool of Nobel Prize winners in Chemistry.

In the current study we also compared women’s representation in chemistry to women’s representation in two other science fields of a Nobel Prize award: (i) Physics and (ii) Physiology or Medicine. Based on our analysis, the numbers of …

Computer Aided Design Of Aromatic Foldamer Targeting Protein-Protein Interaction, Bamidele Towolawi

Graduate Student and Postdoctoral Fellow Symposium

With the computational tools developed in our lab for accurate prediction of structures and solution dynamics of aromatic foldamers, we now target protein-protein interaction (PPI) by appending proteinogenic side chains on the external surfaces of the helical aromatic foldamers. Particularly, the activation of a regulatory protein NF-κB, a key player in the inflammatory response and cell proliferation, involves binding of NEMO (NF-κB Essential Modulator) with linear di-ubiquitin. In this study, we designed various sequences based on established protocols and investigated, by utilizing molecular dynamics (MD) simulations, their potential binding to di-ubiquitin, specifically targeting the NEMO binding interface. This study complements …

Multi-Scale Simulations Of Dynamic Protein Structures And Interactions, Yumeng Zhang

Doctoral Dissertations

Intrinsically disordered proteins (IDPs) are functional proteins that lack stable tertiary structures in the unbound state. They frequently remain dynamic even within specific complexes and assemblies. IDPs are major components of cellular regulatory networks and have been associated with cancers, diabetes, neurodegenerative diseases, and other human diseases. Computer simulations are essential for deriving a molecular description of the disordered protein ensembles and dynamic interactions for mechanistic understanding of IDPs in biology, diseases, and therapeutics. However, accurate simulation of the heterogeneous ensembles and dynamic interactions of IDPs is extremely challenging because of both the prohibitive computational cost and demanding force field …

High Resolution Mass Spectrometry As A Platform For The Analysis Of Polyoxometalates, Their Solution Phase Dynamics, And Their Biological Interactions., Daniel T. Favre

Doctoral Dissertations

Polyoxometalates (POMs) are a class of inorganic molecule of increasing interest to the inorganic, bioinorganic and catalytic communities among many others. While their prevalence in research has increased, tools and methodologies for the analysis of their fundamental characteristics still need further development. Decavanadate (V10) specifically has been postulated to have several unique properties that have not been confirmed independently. Mass spectrometry (MS) and its ability to determine the composition of solution phase species by both mass and charge is uniquely well suited to the analysis of POMs. In this work we utilized high-resolution mass spectrometry to characterize V10 in aqueous …

Methionyl-Trna Synthetase Synthetic And Proofreading Activities Are Determinants Of Antibiotic Persistence, Whitney N. Wood, Miguel Angel Rubio, Lorenzo Eugenio Leiva, Gregory J. Phillips, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Bacterial antibiotic persistence is a phenomenon where bacteria are exposed to an antibiotic and the majority of the population dies while a small subset enters a low metabolic, persistent, state and are able to survive. Once the antibiotic is removed the persistent population can resuscitate and continue growing. Several different molecular mechanisms and pathways have been implicated in this phenomenon. A common mechanism that may underly bacterial antibiotic persistence is perturbations in protein synthesis. To investigate this mechanism, we characterized four distinct metG mutants for their ability to increase antibiotic persistence. Two metG mutants encode changes near the catalytic site …

Size Limits And Fission Channels Of Doubly Charged Noble Gas Clusters, Ianessa Stromberg, Stefan Bergmeister, Lisa Ganner, Fabio Zappa, Paul Scheier, Olof Echt, Elisabeth Gruber

Faculty Publications

Small, highly charged liquid droplets are unstable with respect to spontaneous charge separation when their size drops below the Rayleigh limit or, in other words, their fissility parameter X exceeds the value 1. The absence of small doubly charged atomic cluster ions in mass spectra below an element-specific appearance size n_a has sometimes been attributed to the onset of barrierless fission at X = 1. However, more realistic models suggest that n_a marks the size below which the rate of fission surpasses that of competing dissociative channels, and the Rayleigh limit of doubly charged van der Waals clusters …

In Silico Analysis Of C-Type Lectins As Co-Infection Receptors Of Dengue And Chikungunya Viruses In Aedes Aegypti, Munawir Sazali, R. C. Hidayat Soesilohadi, Nastiti Wijayanti, Tri Wibawa, Arif Nur Muhammad Ansori

Makara Journal of Science

Aedes aegypti is a primer vector of dengue virus (DENV) and chikungunya virus (CHIKV). The susceptibility of mosquitoes to DENV and CHIKV depends on their recognition receptor of pathogens. C-type lectins (CTLs) are an important mediator of virus infection in A. aegypti. This study aims to identify potential receptors and determine the binding affinity between ligand–receptor interaction, CTLs and virus envelopes (DENV-1, 2, 3, and 4 and CHIKV) interaction based on in silico analysis. Sample sequences were obtained from GenBank (NCBI), and 10 CTLs were acquired from VectorBase. Homology modeling based on a minimum standard of 20% was processed …