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2021

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Articles 2881 - 2910 of 27885

Full-Text Articles in Physical Sciences and Mathematics

Smart Contract Development: Challenges And Opportunities, Weiqin Zou, David Lo, Pavneet Singh Kochhar, Xuan-Bach D. Le, Xin Xia, Yang Feng, Zhenyu Chen, Baowen Xu Oct 2021

Smart Contract Development: Challenges And Opportunities, Weiqin Zou, David Lo, Pavneet Singh Kochhar, Xuan-Bach D. Le, Xin Xia, Yang Feng, Zhenyu Chen, Baowen Xu

Research Collection School Of Computing and Information Systems

Smart contract, a term which was originally coined to refer to the automation of legal contracts in general, has recently seen much interest due to the advent of blockchain technology. Recently, the term is popularly used to refer to low-level code scripts running on a blockchain platform. Our study focuses exclusively on this subset of smart contracts. Such smart contracts have increasingly been gaining ground, finding numerous important applications (e.g., crowdfunding) in the real world. Despite the increasing popularity, smart contract development still remains somewhat a mystery to many developers largely due to its special design and applications. Are there …


Themes, Communities And Influencers Of Online Probiotics Chatter: A Retrospective Analysis From 2009-2017, Santosh Vijaykumar, Aravind Sesagiri Raamkumar, Kristofor Mccarty, Cuthbert Mutumbwa, Jawwad Mustafa, Cyndy Au Oct 2021

Themes, Communities And Influencers Of Online Probiotics Chatter: A Retrospective Analysis From 2009-2017, Santosh Vijaykumar, Aravind Sesagiri Raamkumar, Kristofor Mccarty, Cuthbert Mutumbwa, Jawwad Mustafa, Cyndy Au

Research Collection Lee Kong Chian School Of Business

We build on recent examinations questioning the quality of online information about probiotic products by studying the themes of content, detecting virtual communities and identifying key influencers in social media using data science techniques. We conducted topic modelling (n = 36,715 tweets) and longitudinal social network analysis (n = 17,834 tweets) of probiotic chatter on Twitter from 2009–17. We used Latent Dirichlet Allocation (LDA) to build the topic models and network analysis tool Gephi for building yearly graphs. We identified the top 10 topics of probiotics-related communication on Twitter and a constant rise in communication activity. However the number of …


Taxthemis: Interactive Mining And Exploration Of Suspicious Tax Evasion Group, Yating Lin, Kamkwai Wong, Yong Wang, Rong Zhang, Bo Dong, Huamin Qu, Qinghua Zheng Oct 2021

Taxthemis: Interactive Mining And Exploration Of Suspicious Tax Evasion Group, Yating Lin, Kamkwai Wong, Yong Wang, Rong Zhang, Bo Dong, Huamin Qu, Qinghua Zheng

Research Collection School Of Computing and Information Systems

Tax evasion is a serious economic problem for many countries, as it can undermine the government’s tax system and lead to an unfair business competition environment. Recent research has applied data analytics techniques to analyze and detect tax evasion behaviors of individual taxpayers. However, they have failed to support the analysis and exploration of the related party transaction tax evasion (RPTTE) behaviors (e.g., transfer pricing), where a group of taxpayers is involved. In this paper, we present TaxThemis, an interactive visual analytics system to help tax officers mine and explore suspicious tax evasion groups through analyzing heterogeneous tax-related data. A …


Tradao: A Visual Analytics System For Trading Algorithm Optimization, Ka Wing Tsang, Haotian Li, Fuk Ming Lam, Yifan Mu, Yong Wang, Huamin Qu Oct 2021

Tradao: A Visual Analytics System For Trading Algorithm Optimization, Ka Wing Tsang, Haotian Li, Fuk Ming Lam, Yifan Mu, Yong Wang, Huamin Qu

Research Collection School Of Computing and Information Systems

With the wide applications of algorithmic trading, it has become critical for traders to build a winning trading algorithm to beat the market. However, due to the lack of efficient tools, traders mainly rely on their memory to manually compare the algorithm instances of a trading algorithm and further select the best trading algorithm instance for the real trading deployment. We work closely with industry practitioners to discover and consolidate user requirements and develop an interactive visual analytics system for trading algorithm optimization. Structured expert interviews are conducted to evaluateTradAOand a representative case study is documented for illustrating the system …


The Influence Of Bottom Type And Water Column Stratification On Reef Fish Community Structure At Gray’S Reef National Marine Sanctuary, Bridget Campbell Oct 2021

The Influence Of Bottom Type And Water Column Stratification On Reef Fish Community Structure At Gray’S Reef National Marine Sanctuary, Bridget Campbell

Honors Theses

Understanding the physical and oceanographic differences across reef habitats can help researchers assess how those differences influence fish distribution and community structure, which leads to a better understanding of what a healthy reef system looks like. The traditional methods used to assess fish communities on temperate reefs are limited and often focus solely on either the reef structure or water column conditions alone. An assessment of both data sets yields a more complete understanding of the ecosystem as a whole. In this study, Gray’s Reef National Marine Sanctuary (GRNMS) was surveyed both inside and outside a Marine Protected Area (MPA) …


Socio-Ecological Analysis Of Artisanal Gold Mining In West Africa: A Case Study Of Ghana, Richard Takyi, Rasha Hassan, Badr El Mahrad, Richard Adade Sep 2021

Socio-Ecological Analysis Of Artisanal Gold Mining In West Africa: A Case Study Of Ghana, Richard Takyi, Rasha Hassan, Badr El Mahrad, Richard Adade

Journal of Sustainable Mining

The surge in artisanal gold mining (AGM) activities and the associated environmental impact in Ghana have elicited several stakeholders' attempts to curb the problem. However, due to little understanding of the underlying issues, these efforts have been ineffective. This study aims to use a socio-ecological framework to analyze drivers of AGM activities, the environmental pressures, the state change, their impact on human welfare, and the management response as measures (DAPSI(W)R(M)) to the problem. Evaluate AGM's impact on Ghana's ability to achieve the United Nations Sustainable Development Goals (SDGs). Data were collected from relevant literature on the subject and analyzed with …


Characterization Of Extracellular Vesicles By Surface-Enhanced Raman Spectroscopy, Nina M. Culum Sep 2021

Characterization Of Extracellular Vesicles By Surface-Enhanced Raman Spectroscopy, Nina M. Culum

Electronic Thesis and Dissertation Repository

Extracellular vesicles (EVs), which are nanoscale vesicles secreted by cells into biofluids, are of research interest due to their roles in intercellular communication. EVs released from mesenchymal stromal cells (MSCs) have tremendous potential in cell-free regenerative medicine, while EVs released from diseased cells are being studied as biomarkers for minimally invasive and early disease detection. Presented in this thesis are gold nanohole arrays for the capture and sensitive detection of EVs by surface-enhanced Raman spectroscopy (SERS), a plasmonic technique capable of single molecule detection. Herein, we have characterized EVs released from MSCs and ovarian cancer cells, with a focus on …


Internet Of Things Software And Hardware Architectures And Their Impacts On Forensic Investigations: Current Approaches And Challenges, Abel Alex Boozer, Arun John, Tathagata Mukherjee Sep 2021

Internet Of Things Software And Hardware Architectures And Their Impacts On Forensic Investigations: Current Approaches And Challenges, Abel Alex Boozer, Arun John, Tathagata Mukherjee

Journal of Digital Forensics, Security and Law

The never-before-seen proliferation of interconnected low-power computing devices, patently dubbed the Internet of Things (IoT), is revolutionizing how people, organizations, and malicious actors interact with one another and the Internet. Many of these devices collect data in different forms, be it audio, location data, or user commands. In civil or criminal nature investigations, the data collected can act as evidence for the prosecution or the defense. This data can also be used as a component of cybersecurity efforts. When data is extracted from these devices, investigators are expected to do so using proven methods. Still, unfortunately, given the heterogeneity in …


The Survey On Cross-Border Collection Of Digital Evidence By Representatives From Polish Prosecutors’ Offices And Judicial Authorities, Paweł Olber Dr Sep 2021

The Survey On Cross-Border Collection Of Digital Evidence By Representatives From Polish Prosecutors’ Offices And Judicial Authorities, Paweł Olber Dr

Journal of Digital Forensics, Security and Law

Dynamic development of IT technology poses new challenges related to the cross-border collection of electronic evidence from the cloud. Many times investigators need to secure data stored on foreign servers directly and then look for solutions on how to turn the data into a legitimate source of evidence. To study the situation and propose solutions, I conducted a survey among Polish representatives of public prosecutors' offices and courts. This paper presents information from digital evidence collection practices across multiple jurisdictions. I stated that representatives from the prosecution and the judiciary in Poland are aware of the issues associated with cross-border …


Spatial And Time Distribution Of Dairy Cattle Manure In An Intensive Pasture System, S. L. White, S. P. Washburn, L. D. King, R. E. Sheffield, J. T. Green Jr. Sep 2021

Spatial And Time Distribution Of Dairy Cattle Manure In An Intensive Pasture System, S. L. White, S. P. Washburn, L. D. King, R. E. Sheffield, J. T. Green Jr.

IGC Proceedings (1993-2023)

This study determined distribution of feces and urine from dairy cattle managed in a rotationally grazed pasture. Lactating Holsteins (n=18) and Jerseys (n=18) were grazed on a .74 ha endophyte-free fescue (Festuca arundinacea)/white clover (Trifolium repens) pasture. All cows were constantly observed for 24 h 6 times over 12 mo. Cows had access to about 54% of the paddock during the first grazing period (12 h) and had access to the entire paddock during the second grazing period (8 h). Data included: (1) all feces and urine events from eight cows, observed while in the pasture, …


Response Of Mixed C4 Grasses To Various Multiple Paddock Grazing Strategies, B. E. Anderson, W. H. Schacht Sep 2021

Response Of Mixed C4 Grasses To Various Multiple Paddock Grazing Strategies, B. E. Anderson, W. H. Schacht

IGC Proceedings (1993-2023)

The botanical composition of mixed grass pastures may change during grazing due to the various grazing period/recovery period lengths associated with multiple-paddock grazing strategies. This 4-year study compared changes in relative species composition and basal plant cover of a C4 grass mixture grazed using a nested paddock design to simulate 2, 4, 6 and 12- paddock grazing cells in eastern Nebraska. Total basal plant cover declined from 11.6% prior to grazing to 7.3% after one year of grazing and then remained nearly constant thereafter. Neither relative species composition nor basal density were affected greatly by grazing strategy. Within grazing …


Test Of A Conversion Equation To Increase The Accuracy Of Microhistological Analysis Of Herbivore Diets In The Pantanal, S. A. Santos, C. Costa, A. Pott, J. M. Alvarez Sep 2021

Test Of A Conversion Equation To Increase The Accuracy Of Microhistological Analysis Of Herbivore Diets In The Pantanal, S. A. Santos, C. Costa, A. Pott, J. M. Alvarez

IGC Proceedings (1993-2023)

Forty forage species samples were collected in September 1999, including grass, sedges, forbs, shrubs and trees. Seven hand-compounded mixtures of known botanical composition and dry weight were prepared. Five slides of each mixture were made and 20 frequency observations were recorded per slide. Two procedures were used to determine percent composition on a dry weight basis and their values were converted to correct the proportion of the unidentifiable fragments amongst species. Estimated and actual values differed significantly (P < 0.05) in 31.7%, 34.1%, 12.2% and 12.2% of the species for frequency addition (FA), density convertion (DC), frequency addition converted (FAC) and density convertion converted (DCC), respectively. The average similarity values between estimated and observed mixture were 90.2, 86.0, 94.2 and 93.3 for FA, DC, FAC and DCC, respectively. In conclusion, food habits by microscopic analysis may be described using any of the procedures tested because they rank important forage species for herbivores.


Effects Of Herbage Allowance Upon Animal Performance And Grazing Behavior Of Strip-Grazed Heifers, Claudio F. Machado, F. Di Croce, F. Gonzalez, H. Zeballos, N. J. Auza, M. H. Wade, S. T. Morris, J. Hodgson Sep 2021

Effects Of Herbage Allowance Upon Animal Performance And Grazing Behavior Of Strip-Grazed Heifers, Claudio F. Machado, F. Di Croce, F. Gonzalez, H. Zeballos, N. J. Auza, M. H. Wade, S. T. Morris, J. Hodgson

IGC Proceedings (1993-2023)

A trial was designed to test the effect of herbage allowance (HA) on live-weight gain (LWG) and grazing behavior of heifers during spring as part of a combined field-modeling research programme. Low HA (L) and high HA (H) of 2.5 and 5.0 kg DM herbage mass 100 kg animal LW-1day-1 were fed respectively. H animals grazed longer and achieved a higher LWG than L (P < 0.05). H animals left a higher residual pasture (P < 0.051) with a significantly (P < 0.05) higher content of green, clover, non-lamina and petiole of a higher digestibility and NSC, with a lower NDF content. The significance of some factors involved in these results on intake and diet selection are discussed in relation to the predictability of animal performance.


Hydrocracking Of Octacosane And Cobalt Fischer–Tropsch Wax Over Nonsulfided Nimo And Pt-Based Catalysts, Wenping Ma, Jungshik Kang, Gary Jacobs, Shelley D. Hopps, Burtron H. Davis Sep 2021

Hydrocracking Of Octacosane And Cobalt Fischer–Tropsch Wax Over Nonsulfided Nimo And Pt-Based Catalysts, Wenping Ma, Jungshik Kang, Gary Jacobs, Shelley D. Hopps, Burtron H. Davis

Center for Applied Energy Research Faculty and Staff Publications

The effect of activation environment (N2, H2 and H2S/H2) on the hydrocracking performance of a NiMo/Al catalyst was studied at 380 °C and 3.5 MPa using octacosane (C28). The catalyst physical structure and acidity were characterized by BET, XRD, SEM-EDX and FTIR techniques. The N2 activation generated more active nonsulfided NiMo/Al catalyst relative to the H2 or H2S activation (XC28, 70–80% versus 6–10%). For a comparison, a NiMo/Si-Al catalyst was also tested after normal H2 activation and showed higher activity at the same process …


Tectonic Transport Directions, Shear Senses And Deformation Temperatures Indicated By Quartz C-Axis Fabrics And Microstructures In A Nw-Se Transect Across The Moine And Sgurr Beag Thrust Sheets, Caledonian Orogen Of Northern Scotland, Richard D. Law, J. Ryan Thigpen, Sarah E. Mazza, Calvin A. Mako, Maarten Krabbendam, Brandon M. Spencer, Kyle T. Ashley, Robin A. Strachan, Ella F. Davis Sep 2021

Tectonic Transport Directions, Shear Senses And Deformation Temperatures Indicated By Quartz C-Axis Fabrics And Microstructures In A Nw-Se Transect Across The Moine And Sgurr Beag Thrust Sheets, Caledonian Orogen Of Northern Scotland, Richard D. Law, J. Ryan Thigpen, Sarah E. Mazza, Calvin A. Mako, Maarten Krabbendam, Brandon M. Spencer, Kyle T. Ashley, Robin A. Strachan, Ella F. Davis

Earth and Environmental Sciences Faculty Publications

Moine metasedimentary rocks of northern Scotland are characterized by arcuate map patterns of mineral lineations that swing progressively clockwise from orogen-perpendicular E-trending lineations in greenschist facies mylonites above the Moine thrust on the foreland edge of the Caledonian Orogen, to S-trending lineations at higher structural levels and metamorphic grades in the hinterland. Quartz c-axis fabrics measured on a west to east coast transect demonstrate that the lineations developed parallel to the maximum principal extension direction and therefore track the local tectonic transport direction. Microstructures and c-axis fabrics document a progressive change from top to the N shearing in the hinterland …


Percy Julian And The Rise In Inclusive Pedagogy In The Department Of Chemistry And Biochemistry, Jeff Hansen, Jacqueline Roberts, Richard Martoglio Sep 2021

Percy Julian And The Rise In Inclusive Pedagogy In The Department Of Chemistry And Biochemistry, Jeff Hansen, Jacqueline Roberts, Richard Martoglio

President Lori S. White Inauguration Symposium

As a research fellow at DePauw, Dr. Percy L. Julian included undergratuate students in his research to synthesize physostigmine. Building on that legacy, the Department of Chemistry and Biochemistry continues a longstanding history of supporting undergraduate research. Recongnizing tht there is inequity in who participates in research, our department recently initiated an application process open to all students in our courses to equalize the way in which stuents learn about and get started in research. Students in our structure and propterties of organiz molecules course view and reflect on the Forgotten Genius documentary and the recently awarded HHMU Inclusive Excellence …


Methodology For Solving The Radiation Problem Proposed By Planck In Physics On The Basis Of The Principle Of Consistency, Raygul Khozhanazarova Sep 2021

Methodology For Solving The Radiation Problem Proposed By Planck In Physics On The Basis Of The Principle Of Consistency, Raygul Khozhanazarova

Karakalpak Scientific Journal

  1. www.quantumphysics.iop.org
  2. М. Planck. Verhandl. Dtsch. phys. Ges., 1900, 2, 237-245. М. Planck. Ann. Phys., 1901, 4, 553-563.
  3. M. Planck, Zur Theorie des Gesetzes der Energieverteilung im Normalspektrum, ibid., 237-245 (1900)/
  4. M. Planck. Uber des Gesetz der Energieverteilung im Normalspektrum, Ann. d.Phys. 4, 553—563 (1901).
  5. Maks Plank. 1858-1958: Sb. k stoletiyu so dnya rozhdeniya Maksa Planka / Pod red. A. F. Ioffe i A. T. Grigor'yana. M.: Izd-vo AN SSSR, 1958. 276 p.
  6. L. Boltzmann. Populare Schriften. Leipzig 1905, p. 227.
  7. M.Plank. Vvedeniye v teoreticheskuyu fiziku. Chast' pyataya. Teoriya teploty. Ob"yedinennoye nauchno-tekhnicheskoye izdatel'stvo NKTP SSSR. Glavnaya redaktsiya obshchetekhnicheskoy literatury i nomografii. …


Fe-Catalyzed Sulfide Oxidation In Hydrothermal Plumes Is A Source Of Reactive Oxygen Species To The Ocean, Timothy J. Shaw, George W. Luther Iii, Richard Rosas, Véronique E. Oldham, Nicole R. Coffey, John L. Ferry, Dewamunnage M. C. Dias, Mustafa Yücel, Aubin Thibault De Chanvalon Sep 2021

Fe-Catalyzed Sulfide Oxidation In Hydrothermal Plumes Is A Source Of Reactive Oxygen Species To The Ocean, Timothy J. Shaw, George W. Luther Iii, Richard Rosas, Véronique E. Oldham, Nicole R. Coffey, John L. Ferry, Dewamunnage M. C. Dias, Mustafa Yücel, Aubin Thibault De Chanvalon

Faculty Publications

Historically, the production of reactive oxygen species (ROS) in the ocean has been attributed to photochemical and biochemical reactions. However, hydrothermal vents emit globally significant inventories of reduced Fe and S species that should react rapidly with oxygen in bottom water and serve as a heretofore unmeasured source of ROS. Here, we show that the Fe-catalyzed oxidation of reduced sulfur species in hydrothermal vent plumes in the deep oceans supported the abiotic formation of ROS at concentrations 20 to 100 times higher than the average for photoproduced ROS in surface waters. ROS (measured as hydrogen peroxide) were determined in hydrothermal …


Neural Network Learning Of Improved Compressive Sensing Sampling And Receptive Field Structure, Victor J. Barranca Sep 2021

Neural Network Learning Of Improved Compressive Sensing Sampling And Receptive Field Structure, Victor J. Barranca

Mathematics & Statistics Faculty Works

While the theory of compressive sensing (CS) in modern signal processing typically indicates that uniformly random sampling facilitates the efficient recovery of sparse signals, such measurements are infeasible in many engineering applications and are not well reflected by the constraints of natural systems, including neuronal networks in the brain. Uniformly random sampling also does not leverage the underlying structure of many classes of signals, and may therefore be suboptimal in these cases. We address these issues by formulating a novel neural network framework for learning improved CS sampling based on the intrinsic structure present in classes of training signals. Beyond …


Mgrre_Pureoilscouttickets_Phillips_1_21127016170000, Mgrre Sep 2021

Mgrre_Pureoilscouttickets_Phillips_1_21127016170000, Mgrre

Legacy Scout Tickets from Pure Oil Company

No abstract provided.


Rapid Quantitative Analysis Of Toxic Norditerpenoid Alkaloids In Larkspur (Delphinium Spp.) By Flow Injection - Electrospray Ionization – Mass Spectrometry, Dale R. Gardner, Stephen T. Lee, Daniel Cook Sep 2021

Rapid Quantitative Analysis Of Toxic Norditerpenoid Alkaloids In Larkspur (Delphinium Spp.) By Flow Injection - Electrospray Ionization – Mass Spectrometry, Dale R. Gardner, Stephen T. Lee, Daniel Cook

Poisonous Plant Research (PPR)

A rapid flow injection - electrospray ionization – mass spectrometry (FI-ESI-MS) method for the quantitative and qualitative analysis of norditerpenoid alkaloids in larkspur plants was developed. The FI-ESI-MS method was calibrated for alkaloid concentrations with larkspur plant samples against an existing Fourier transform infrared spectroscopy FTIR method. There was a strong correlation (r = 0.9926, r = 0.9891) between the FTIR and FI-ESI-MS methods. The relative standard deviation (RSD) for all measurements were ≤ 6.2 % except for the sample with the lowest concentration which was 19%. The sample throughput of the FI-ESI-MS method is much higher than the FTIR …


Analysis On The Crystal Structure Of The Piezoelectric Nanocrystal Ceramic Of Pr-Doped Bi1/2na1/2tio3 Using Molten-Salt Synthesis, Syahfandi Ahda, Vita Ambarwati, Mardiyanto Mardiyanto, Engkir Sukirman, Bambang Sugeng Sep 2021

Analysis On The Crystal Structure Of The Piezoelectric Nanocrystal Ceramic Of Pr-Doped Bi1/2na1/2tio3 Using Molten-Salt Synthesis, Syahfandi Ahda, Vita Ambarwati, Mardiyanto Mardiyanto, Engkir Sukirman, Bambang Sugeng

Makara Journal of Science

One of the future technologies in nuclear reactors is the ability of piezoelectric materials to monitor reactor cores as sensors. Particularly, Pb-free piezoelectric materials, such as Bi1/2Na1/2TiO3, have been examined to improve the ability of their piezoelectric properties. In this study, we attempted to add Pr6O11 dopant material with mole ratios of 0, 0.3, 0.5, and 0.7 mol%. The synthesis process used in this study is the molten-salt synthesis method with a NaCl and KCl salt mole ratio of 1:1. The crystal structure analysis using the refinement process of the Rietveld …


Synthesis And Characterization Of Cellulose Acetate Membrane From Cotton Spinning Waste, Silvy Djayanti, Syarifa Arum Kusumastuti, Januar Fatkhurrahman, Agus Purwanto, Agung Budiarto, Alex Lukmanto Suherman Sep 2021

Synthesis And Characterization Of Cellulose Acetate Membrane From Cotton Spinning Waste, Silvy Djayanti, Syarifa Arum Kusumastuti, Januar Fatkhurrahman, Agus Purwanto, Agung Budiarto, Alex Lukmanto Suherman

Makara Journal of Science

Cellulose acetate membrane (CAM) was successfully synthesized and characterized from the cotton spinning waste of the textile industry. The membrane was produced through the isolation, acetylation, and phase inversion stages. The highest yields of cellulose fiber and α-cellulose contents were obtained using 3.0% and 6.0% v/v NaClO, respectively. The C–O acetyl bond detected by Fourier Transform Infrared (FTIR) analysis indicates the formation of the CAM. The resulting membrane can be potentially applied as an ultrafiltration membrane for water desalination purposes in water and wastewater treatment facilities. Furthermore, the utilization of cotton spinning waste as raw material aims to produce inexpensive …


Synthesis And Complexation Of Monotosylated 4-Aminopyridine With Nickel (Ii) And Iron (Ii) Ions, Kingsley John Orie, Remy Ukachukwu Duru, Raphael I-Oro Ngochindo Sep 2021

Synthesis And Complexation Of Monotosylated 4-Aminopyridine With Nickel (Ii) And Iron (Ii) Ions, Kingsley John Orie, Remy Ukachukwu Duru, Raphael I-Oro Ngochindo

Makara Journal of Science

Tosylated 4-aminopyridine and other sulfonylated compounds of amines comprise a substantial class of pharmaceutical drugs used as antibiotics in the field of medicine. This research aimed at the synthesis of tosylated 4-aminopyridine and the complexation of the tosyated 4-aminopyridine with Ni(II) and Fe(II) ions. The sulfonamide was prepared by the action of tosyl chloride on 4-aminopyridine in an aqueous alkaline medium. The complexes were synthesized by the reaction of Ni(NO3)2.6H2O /Fe(NO3)2.6H2O with sulfonamide derivative. These compounds were characterized through Ultraviolet Visible spectroscopy (UV–Vis), Fourier Transform Infer-Red (FTIR) spectroscopy, …


Effects Of Different Extraction Solvents On The Extractive Removal And Properties Of Oil Palm Empty-Fruit Bunch Cellulosic Nanofibers, Achmad Solikhin, Yusuf Sudo Hadi, Muh Yusram Massijaya, Siti Nikmatin Sep 2021

Effects Of Different Extraction Solvents On The Extractive Removal And Properties Of Oil Palm Empty-Fruit Bunch Cellulosic Nanofibers, Achmad Solikhin, Yusuf Sudo Hadi, Muh Yusram Massijaya, Siti Nikmatin

Makara Journal of Science

In this study, the effect of different extraction solvents on the isolation and properties of cellulosic nanofibers (CNFs) were investigated. The unextracted and different solvent-extracted CNFs formed horn-like features and irregularly aggregated nanofibers after oven drying. Scanning electron microscopy at 10000× magnification revealed the smooth external surfaces of all extracted CNFs; this finding is attributed to the limited deposition of amorphous lignocellulosic components on the fibers. All resultant CNF solutions revealed aggregation, with a particle size distribution and zeta average of 21.39–513.00 nm and 162.26–342.13 nm, respectively. Extraction with different solvents and chemical treatment yielded CNF solutions with good transparency. …


Hemoglobin-Modified Core–Shell Fe3o4@Au Nanostructures For The Electrochemical Detection Of Acrylamide, Endang Saepudin, Tri Yuliani, Mochammad Arfin Fardiansyah Nasution, Munawar Khalil, Jong Wook Hong, Tribidasari Anggraningrum Ivandini Sep 2021

Hemoglobin-Modified Core–Shell Fe3o4@Au Nanostructures For The Electrochemical Detection Of Acrylamide, Endang Saepudin, Tri Yuliani, Mochammad Arfin Fardiansyah Nasution, Munawar Khalil, Jong Wook Hong, Tribidasari Anggraningrum Ivandini

Makara Journal of Science

In this study, electrochemical detection of acrylamide using hemoglobin (Hb)-modified core–shell Fe3O4@Au nanostructures was conducted. Fe3O4 nanoparticles (~4.9 nm) and core–shell Fe3O4@Au (5.0–6.4 nm) nanostructures were successfully synthesized by the thermal decomposition method. Electrochemical investigation revealed that the optimum amount of Hb of 2 mg/mL could be immobilized in 0.1 M acetate buffer solution (pH = 6). Moreover, the detection of acrylamide using Fe3O4@Au/Hb was evaluated by the cyclic voltammetry technique. A linear calibration curve (R2 = 0.98) in the concentration range of …


Thermal Analysis Of Benzotriazolium Perrhenate And Its Implication To Rhenium Metal, James Louis-Jean, Harry Jang, Andrew J. Swift, Frederic Poineau Sep 2021

Thermal Analysis Of Benzotriazolium Perrhenate And Its Implication To Rhenium Metal, James Louis-Jean, Harry Jang, Andrew J. Swift, Frederic Poineau

Chemistry and Biochemistry Faculty Research

The thermal analysis behavior of C6H6N3[ReO4] was studied by simultaneous thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC) up to 700 °C under argon. Such analysis afforded rhenium metal, which was characterized by powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), and energy-dispersive X-ray (EDX) spectroscopy. XRD peak broadening due to crystallite size and lattice strain was analyzed by both Williamson-Hall (W-H) and Debye-Scherrer (D-S) methods. Efforts to isolate Re metal from the thermal treatment of benzotriazole (BTA = C6H5N3) with NH4ReO4 and Re2O7 under various atmospheres and temperatures are also reported. The results provide a significant insight into …


Prevention And Preparedness Of The Messina-Reggio Calabria Strait: An Earthquake Forecasting And Didactic Project, Francesco Di Stefano, Gioacchino Giampaolo Giuliani, Dimitar Ouzounov, Daniele Cataldi, Cristiano Fidani, Angelo D'Errico, Giulia Fioravanti Sep 2021

Prevention And Preparedness Of The Messina-Reggio Calabria Strait: An Earthquake Forecasting And Didactic Project, Francesco Di Stefano, Gioacchino Giampaolo Giuliani, Dimitar Ouzounov, Daniele Cataldi, Cristiano Fidani, Angelo D'Errico, Giulia Fioravanti

Mathematics, Physics, and Computer Science Faculty Articles and Research

This contribution is addressed to an introductive university course on the correlation existing between radon emission and earthquakes processes held following a flipped-class approach where students receive didactic materials prior to face-to-face lessons. This research was initially started to investigate the real correlation between Radon emission from the Earth and the occurrence of strong earthquakes by using measurements of hourly Radon flow variation. During quiet seismogenic conditions, we observe an unvarying level of Radon emission in the air. Before a strong earthquake, substantial variations of Radon (222Rn) concentration have been observed in the air, probably because of the …


Factors Influencing The Yield Proportions Of Plantago Lanceolata L. And Taraxacum Officinale Web. In Lolium Perenne L. Swards, Harald Laser Sep 2021

Factors Influencing The Yield Proportions Of Plantago Lanceolata L. And Taraxacum Officinale Web. In Lolium Perenne L. Swards, Harald Laser

IGC Proceedings (1993-2023)

Diaspores of Plantago lanceolata and Taraxacum officinale respectively were sown in established Lolium perenne swards to determine the dynamics of their yield proportions during five years. The experimental factors were forb species, variety of the grass species (= early or late flowering), N-fertilization, and sward density. The amount of nitrogen fertilizer had the most important effect on yield proportions of the forb species and also on the total dry-matter (= DM) yield. The single creation of gaps in grass swards before sowing forbs had a lasting positive effect on the Plantago lanceolata and Taraxacum officinale proportions. Peak proportions of Taraxacum …


Dynamic Of Native Pasture Influenced By Deferment Of Grazing And Fertilization, K. E. Gomes, G. E. Maraschin, J. Riboldi Sep 2021

Dynamic Of Native Pasture Influenced By Deferment Of Grazing And Fertilization, K. E. Gomes, G. E. Maraschin, J. Riboldi

IGC Proceedings (1993-2023)

Native pastures of southern Brazil cover 12 million ha and are the main forage feed resource for most domestic livestock. However, their heavy and continuous use has reduced standing biomass and the presence of good forage species, reducing animal performance and jeopardizing the ecosystem sustainability. An alternative for better use of these pastures and their preservation is grazing deferment that allow natural reseeding. The objective of this research was evaluate native pasture dynamic after six years of grazing deferments (GD) periods and soil fertilization effects by point-quadrat method every season. All pasture components were affected by GD, with prostrate grasses …