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Articles 31591 - 31620 of 294453

Full-Text Articles in Physical Sciences and Mathematics

Herding Livestock – The Phoenix Rises From The Ashes? Digital Herding As A Future Tool For Grazing Livestock, J. Horn, R. Reisch, M. Komainda, P. Riedel, J. Isselstein Feb 2024

Herding Livestock – The Phoenix Rises From The Ashes? Digital Herding As A Future Tool For Grazing Livestock, J. Horn, R. Reisch, M. Komainda, P. Riedel, J. Isselstein

IGC Proceedings (1977-2023)

Today, sustainable management of grazing livestock requires high efforts in management and fencing. Nowadays, several developments in digital technologies for herding grazing animals are arising. We conducted a systematic review on current developments in digital technologies for managing grazing animals within the landscape. We mainly focused on cattle (Bos taurus) and sheep (Ovis aries). We highlight the most promising developments of virtual fencing used in recent research to evaluate effectiveness, animal behaviour and welfare. Moreover, we highlight current research in digital herding by drones and robots. We discuss the potential and current limitations of digital tools …

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Development Of Megathyrsus Maximus Genotypes For Intensification Of Cattle Rearing In Brazil, Liana Jank, M. F. Santos, Sanzio Carvalho Barrios, Cacilda Borges Do Valle, Rosangela Maria Simeão Feb 2024

Development Of Megathyrsus Maximus Genotypes For Intensification Of Cattle Rearing In Brazil, Liana Jank, M. F. Santos, Sanzio Carvalho Barrios, Cacilda Borges Do Valle, Rosangela Maria Simeão

IGC Proceedings (1977-2023)

Megathyrsus maximus is a forage species used over 30 million hectares in Brazil and in the surrounding countries for intensification of the cattle production systems. Due to the large area and distinct biomes in which it is used, there is a need to continuously develop more productive and adapted cultivars to each biome and use. Three apomictic accessions were crossed with five sexual plants at Embrapa Beef Cattle in Campo Grande, MS, Brazil in 2014. More than 1100 hybrids were planted in a spaced-plant field and evaluated visually for regrowth after cuts and for disease and pest damage. In 2016, …

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Scaled Datasets Through Leveraging Technology Better Represent Plant Communities Classified Within National Land Cover Database (Nlcd), D. M. Johnston, D. B. Murray, Y. Y. Tsang Feb 2024

Scaled Datasets Through Leveraging Technology Better Represent Plant Communities Classified Within National Land Cover Database (Nlcd), D. M. Johnston, D. B. Murray, Y. Y. Tsang

IGC Proceedings (1977-2023)

Technological advances in remote sensing have allowed for access to and application of large- scale datasets of plant communities using cover classification and chlorophyll content measurement with the use of multispectral sensors and vegetation indices. The United States’ primary remote sensing platform Landsat Thematic Mapper is a series of satellites providing 30-meter resolution imagery of the Earth’s surface. Efforts have been made to best utilize Landsat derivative National Land Cover Database (NLCD) datasets and provide spatial resolution commensurate with the needs of plant ecologists and range managers. However, usage of 30-meter spatial resolution imagery and indices does not allow detection …

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Heavy Grazing Significantly Reduced The Temporal Stability Of Aboveground Biomass, X. Ju, T. T. Shen, Q. Wu, G. D. Han Feb 2024

Heavy Grazing Significantly Reduced The Temporal Stability Of Aboveground Biomass, X. Ju, T. T. Shen, Q. Wu, G. D. Han

IGC Proceedings (1977-2023)

The stability of a plant community is the embodiment of the dynamic balance achieved by the interaction between populations in the form of competition or mutual benefit. Temporal stability refers to the ratio of the average value to the variance of the biomass of the population or community. For grassland ecosystems, the stability of the grassland plant community is the basis for its survival and functional performance, and is the key factor affecting its structure and function. In order to study the impact of grazing on the temporal stability of aboveground biomass of desert steppe, this study used a completely …

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Migration And Colonization Characteristics Of Endophytic Tracer Rhizobia To The Reproductive Organs Of Alfalfa, W. J. Kang, S. L. Shi, Y. T. Zhang, L. Y. Chen Feb 2024

Migration And Colonization Characteristics Of Endophytic Tracer Rhizobia To The Reproductive Organs Of Alfalfa, W. J. Kang, S. L. Shi, Y. T. Zhang, L. Y. Chen

IGC Proceedings (1977-2023)

Legume seeds are the product of long-term natural selection and the co-evolution of rhizobia and seeds. They are more competitive than the native rhizobia in constructing symbiotic nitrogen-fixing systems with host plants. However, the paths and impact factors of rhizobia invasion and migration in plants, as well as colonization in seeds, are unclear. Here, alfalfa cultivars WL343HQ and Gannong 5, and three cyan fluorescent protein-tagged rhizobia (FTR), 3436f, 12531f and gn5f were used as materials. The effects of potassium dihydrogen phosphate (KH2PO4) and fulvic acid (FA) on the migration and colonization of FTR in the reproductive organs of field plants …

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Spring Grass Availability And Silage Supplementation Impact On Dry Matter Intake And Enteric Methane Emissions In Grazing Dairy Cattle, M. Kennedy, S. Walsh, T. M. Boland, M. Egan Feb 2024

Spring Grass Availability And Silage Supplementation Impact On Dry Matter Intake And Enteric Methane Emissions In Grazing Dairy Cattle, M. Kennedy, S. Walsh, T. M. Boland, M. Egan

IGC Proceedings (1977-2023)

Enteric methane (CH4) emissions were measured in forty spring calving cows offered one of two (n=20) contrasting diets (High Grass; HG, Low Grass; LG) over 10 weeks in early lactation (8th February – 18th April 2021). All cows were blocked for breed and parity and balanced on milk production, economic breeding index (EBI), bodyweight and body condition score and randomly allocated to treatments. The HG grazing treatment cows were offered their full daily nutrient requirement from grazed grass and concentrate with no silage supplementation. The LG grazing treatment cows were offered a restricted (~60%) amount of their daily nutrient requirement …

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Role Of Social Media And Digital Resources In Extension, L. L. Baxter Feb 2024

Role Of Social Media And Digital Resources In Extension, L. L. Baxter

IGC Proceedings (1977-2023)

Social media and digital resources can be powerful tools for Extension personnel as they can enable forage-livestock researchers and Extension specialists to connect with a wide audience of producers, Extension personnel, colleagues, and industry partners. Online platforms that provide a space for Extension personnel to deliver timely information and digital resources have been critical for continuing producer education in today’s environment. This presentation in the thematic session on “Understanding the role of social media and digital resources in forage education and promotion” will focus on the role social media and digital resources play in Extension. There are a host of …

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Creating An Educational Experience That Fosters Diversity And Inclusion, M. M. Kohmann Feb 2024

Creating An Educational Experience That Fosters Diversity And Inclusion, M. M. Kohmann

IGC Proceedings (1977-2023)

Demographic, intellectual, and individual diversity have been linked to increase in innovation, problem-solving, critical thinking, and economic gains. However, there are multiple challenges associated with recruiting, retaining, and advancing underrepresented groups in Science, Technology, Engineering, and Mathematics (STEM). Studies have indicated negative implicit bias against women and minorities in terms of their perceived competence, worthiness to be hired, and payment irrespective to their qualification. Additionally, lack of mentoring and access to personal capital often hinder students’ academic advancement in STEM. However, there have been multiple intentional, recent efforts to increase and foster diversity in sciences. Some of the most effective …

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Modeling The Biomass Production Of Grasslands Of Wallonia According To Their Functional Type, U. Kokah Essomandan, D. Knoden, B. Dumont, J. Bindelle Feb 2024

Modeling The Biomass Production Of Grasslands Of Wallonia According To Their Functional Type, U. Kokah Essomandan, D. Knoden, B. Dumont, J. Bindelle

IGC Proceedings (1977-2023)

Permanent grasslands are complex ecosystems which respond with a great variability - in terms of specific richness - to soil type and management strategies. Modelling is a valuable tool to explore these relationships. Our work consisted in adapting the Moorepark St Gilles grass growth model (MoSt GG) designed to model Lolium perenne plant functional type (PFT) pastures (PFT A) to a different PFT (Dactylis glomerata, PFT B) through literature-based parametrization. The model was evaluated under Walloon (Belgium) conditions using growth trials from 2014 to 2018 in two sites with contrasting pedo-climatic conditions. Three to five cuts were performed …

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Assessment Of Soil Structure And Root Patterns By Means Of Micro-X-Ray Computed Tomography In Temperate Grassland Sites, K. Kuka, M. Joschko Feb 2024

Assessment Of Soil Structure And Root Patterns By Means Of Micro-X-Ray Computed Tomography In Temperate Grassland Sites, K. Kuka, M. Joschko

IGC Proceedings (1977-2023)

Grassland sites are important ecosystems delivering essential ecosystem services such as carbon storage and filtering of water. Adequate management necessitates a better understanding of soil ecological processes in grassland ecosystems. Of special interest is the relationship between soil structure and root development. In a project within the Biodiversity Exploratory Initiative (http://www.biodiversity-exploratories.de), undisturbed soil cores from 31 grassland plots from Swabian Alb Biodiversity exploratory in Germany were investigated by means of X-ray micro computed tomography. This allows the simultaneous determination of soil physical and root parameters in one sample. VG StudioMax® version 2.1 was used to apply a combination of histogram …

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Spatio-Temporal Dynamics Of The Dual-Purpose Cattle Value Chain In The Colombian Amazonas, A. Leinert, S. Burkart Feb 2024

Spatio-Temporal Dynamics Of The Dual-Purpose Cattle Value Chain In The Colombian Amazonas, A. Leinert, S. Burkart

IGC Proceedings (1977-2023)

The cattle sector plays an important role in the economy of the Caquetá department, located in the Colombian Amazon. However, the predominantly extensive production system is associated with low productivity and negative environmental impacts, such as land degradation, greenhouse gas emissions, and deforestation. Efforts to introduce improved practices (e.g., improved forages or silvopastoral systems) have been made over the last decades, but adoption rates remain low. Though several studies have analyzed the cattle value chain (VC) to enhance the understanding of adoption barriers, the heterogeneity of farmers has been considered only marginally when trying to explain their adoption behavior. To …

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Predicting Forage Provision Of Grasslands Across Climate Zones By Hyperspectral Measurements, F. A. Männer, J. Muro, J. Ferner, S. Schmidtlein, A. Linstädter Feb 2024

Predicting Forage Provision Of Grasslands Across Climate Zones By Hyperspectral Measurements, F. A. Männer, J. Muro, J. Ferner, S. Schmidtlein, A. Linstädter

IGC Proceedings (1977-2023)

The potential of grasslands’ fodder production is a crucial management measure, while its quantification is still laborious and costly. Remote sensing technologies, such as hyperspectral field measurements, enable fast and non-destructive estimation. However, such methods are still limited in transferability to other locations or climatic conditions. With this study, we aim to predict forage nutritive value, quantity, and energy yield from hyperspectral canopy reflections of grasslands across three climate zones. We took hyperspectral measurements with a field spectrometer from grassland canopies in temperate, tropical and semi-arid grasslands, and analyzed corresponding biomass samples for their quantity (BM), metabolizable energy content (ME) …

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Themeda Triandra As A Perennial Seed Crop In South-Eastern Australia: What Are The Agronomic Possibilities And Constraints, And Future Research Needs?, D. Male, J. Hunt, C. Celestina, J. Morgan, D. Gupta, Dja Dja Wurrung People Feb 2024

Themeda Triandra As A Perennial Seed Crop In South-Eastern Australia: What Are The Agronomic Possibilities And Constraints, And Future Research Needs?, D. Male, J. Hunt, C. Celestina, J. Morgan, D. Gupta, Dja Dja Wurrung People

IGC Proceedings (1977-2023)

In Australia, the development of native perennial seed crops is an area of increasing interest. Reasons for this include the production of high-value seed, the significance of native plants to Aboriginal people and the importance of diversified cropping in building more resilient farming systems. One species of interest is Themeda triandra, a C4 perennial tussock grass that dominated grasslands and woodlands across Australia prior to European invasion. Djaara, the traditional owner group representing the Dja Dja Wurrung people of Djandak (Dja Dja Wurrung country in central Victoria), is one group who seek to return T. triandra to the landscape …

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Quality Of Life In Orthodontics, Claudia Eisenhuth, Gabriel Eisenhuth, Connor Schwartz, Amir Mohajeri, Man Hung, Tiffany Nelson, Ryann Glenn Feb 2024

Quality Of Life In Orthodontics, Claudia Eisenhuth, Gabriel Eisenhuth, Connor Schwartz, Amir Mohajeri, Man Hung, Tiffany Nelson, Ryann Glenn

Annual Research Symposium

Orthodontic treatment goes beyond mere cosmetic enhancement; it significantly impacts various aspects of an individual's quality of life. Beyond the physical benefits of improved oral function and prevention of dental issues, orthodontics also yields profound psychological benefits. Aligned teeth enhance self-confidence, reduce social anxiety, and contribute to better relationships and professional opportunities. Moreover, addressing dental concerns through orthodontic treatment reduces psychological distress and promotes overall happiness and satisfaction. Real-life case studies vividly illustrate the transformative effects of orthodontic interventions, emphasizing the importance of considering quality of life outcomes in dental care.

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Subaqueous Carbonate Speleothems As Paleotemperature Archives – Clumped Isotope Thermometry And Stable Isotope Compositions Of Inclusion-Hosted Water, Attila Demeny, Ágnes Berentés, László Rinyu, Ivett Kovács, Gergely Surányi, Magdolna Virág Feb 2024

Subaqueous Carbonate Speleothems As Paleotemperature Archives – Clumped Isotope Thermometry And Stable Isotope Compositions Of Inclusion-Hosted Water, Attila Demeny, Ágnes Berentés, László Rinyu, Ivett Kovács, Gergely Surányi, Magdolna Virág

International Journal of Speleology

Clumped isotope measurements of carbonates and stable isotope analyses of water trapped in fluid inclusions are both promising techniques to determine carbonate formation temperatures. Cave-hosted carbonate deposits (speleothems) are excellent targets for such studies, but kinetic fractionations and diagenetic influences frequently deteriorate the temperature data obtained from these methods. However, subaqueous carbonate deposits may provide reliable data, as kinetic fractionations are less significant in underwater environments. In this study, subaqueous speleothems, whose formation temperatures were directly measured in the water, were investigated. Additionally, temperatures calculated from the oxygen isotope fractionations between calcite and fluid inclusion-hosted water were compared with clumped …

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Heavy Metal Movement Through Insect Food Chains In Pristine Thermal Springs Of Yellowstone National Park, Braymond Adams, John Bowley, Monica Rohwer, Erik Oberg, Kelly Willemssens, Wendy Wintersteen, Robert K.D. Peterson, Leon G. Higley Feb 2024

Heavy Metal Movement Through Insect Food Chains In Pristine Thermal Springs Of Yellowstone National Park, Braymond Adams, John Bowley, Monica Rohwer, Erik Oberg, Kelly Willemssens, Wendy Wintersteen, Robert K.D. Peterson, Leon G. Higley

School of Natural Resources: Faculty Publications

Yellowstone National Park thermal features regularly discharge various heavy metals and metalloids. These metals are taken up by microorganisms that often form mats in thermal springs. These microbial mats also serve as food sources for invertebrate assemblages. To examine how heavy metals move through insect food webs associated with hot springs, two sites were selected for this study. Dragon-Beowulf Hot Springs, acid-sulfate chloride springs, have a pH of 2.9, water temperatures above 70 oC, and populations of thermophilic bacterial, archaeal, and algal mats. Rabbit Creek Hot Springs, alkaline springs, have a pH of up to 9, some water temperatures …

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A Case For Hope In A Warming World, Noreen L. Herzfeld Feb 2024

A Case For Hope In A Warming World, Noreen L. Herzfeld

Reuter Professorship of Science and Religion Publications

It is difficult to feel hopeful in a rapidly warming world. But hope is not just a feeling. It is an active verb, one that calls for courage, solidarity, a clear vision, and hard work. First, knowing that each fraction of a degree counts, humanity is called not to despair but to use every technology and means, technologies we already have. Second, we can be encouraged by a vision of a new world and society that works for everyone. Third, we can be heartened by nature’s resilience and an evolutionary theology that looks toward the future.

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Recent Advances And Applications Of Nanostructured Membranes In Water Purification, Didem Aydin, İlkay Hilal Gübbük, Mustafa Ersöz Feb 2024

Recent Advances And Applications Of Nanostructured Membranes In Water Purification, Didem Aydin, İlkay Hilal Gübbük, Mustafa Ersöz

Turkish Journal of Chemistry

In recent years, water pollution caused by hazardous materials such as metals, drugs, pesticides, and insecticides has become a very serious environmental and health problem that needs to be addressed urgently. The nutritional needs associated with the increasing population also increase the demand for water use and rapidly increase the rate of freshwater consumption. Since most of the water in the universe is in the form of sea water, which cannot be directly used, freshwater resources are limited ,compared to the existing available water. When addressing the purification of all kinds of pollution in environmental research, nanostructured membranes attract attention …

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Chromium Speciation In Water Using Magnetic Polyaniline Nanoparticles Coupled With Microsampling Injection-Flame Atomic Absorption Spectroscopy, Osman Çaylak Feb 2024

Chromium Speciation In Water Using Magnetic Polyaniline Nanoparticles Coupled With Microsampling Injection-Flame Atomic Absorption Spectroscopy, Osman Çaylak

Turkish Journal of Chemistry

The chromium speciation procedure was optimized using magnetic polyaniline nanoparticles (Fe3O4@PANI NPs) solid-phase extraction coupled with microsampling injection-flame atomic absorption spectrometry (MIS-FAAS). Chromium speciation was successfully achieved by Fe3O4@PANI NPs at pH 8.0. The recoveries obtained for Cr(III) and Cr(VI) were above 95% and under 5%, respectively. Recoveries of over 95% for Cr(III) from 40.0 mL of the sample were obtained using 25 mg Fe3O4@PANI NPs and 500 µL of 0.2% (w/v) thiourea (TU) solution prepared in 2 mol L–1 HCl as eluent. Total chromium as Cr(III) was extracted quantitatively after reducing the Cr(VI) to Cr(III). The linear range, detection …

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Sustainable Bio-Based Solid Phase Extraction Adsorbent For The Determination Of Various Types Of Organic Compounds, Mustafa Zafer Ozel, James H. Clark, Avtar S. Matharu Feb 2024

Sustainable Bio-Based Solid Phase Extraction Adsorbent For The Determination Of Various Types Of Organic Compounds, Mustafa Zafer Ozel, James H. Clark, Avtar S. Matharu

Turkish Journal of Chemistry

A sustainable, bio-based, mesoporous material, Starbon A800, was explored for use as an adsorbent in solid phase extraction (SPE). A solution containing seven nitrosamines was first used as a standard to optimise conditions for extraction efficiency with Starbon A800. After optimising conditions, 25 compounds of varying polarity (terpenes, phenolics, pesticides, PAHs, amines, and nitrosamines) were extracted with SPE using either Starbon® A800, C18 or Porous Graphitic Carbon (PGC) as the adsorbent, for comparison purposes. At the same time, 3 different elution solvents (heptane, dichloromethane, and ethanol) were used for each type of adsorbent. Hansen solubility parameters can be used to …

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Synthesis And Characterization Of Surface-Modified Magnetic Mesoporous Silicate Materials For Phosphate Adsorption, Ayşegül Gençer, Burcu Uysal Karataş, Önder Topel, Nadir Ki̇raz Feb 2024

Synthesis And Characterization Of Surface-Modified Magnetic Mesoporous Silicate Materials For Phosphate Adsorption, Ayşegül Gençer, Burcu Uysal Karataş, Önder Topel, Nadir Ki̇raz

Turkish Journal of Chemistry

The magnetic mesoporous silica material, Mag-MCM-41, was synthesized by coating magnetite (Fe3O4) nanoparticles with a mesoporous material called MCM-41. Mag-MCM-41 and modified nanomaterials Mag-MCM-41-NN and Mag-MCM-41-NN-Fe+3 which were modified with aminopropyl functional groups. In water and wastewater, phosphate anions are considered significant contaminants due to their detrimental impact on the environment. They promote the growth of algae, leading to eutrophication. The purpose of this study is to investigate the removal of phosphate anions from aqueous solutions using modified magnetic silica particles. The Mag-MCM-41 material exhibits hexagonal properties and belongs to the class of “mesoporous” materials. It has a surface area …

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The Effect Of Partial Substitution Of Noble Metal (Pd) At The B Site Of La0.6sr0.4feo3 As A Supercapacitor Electrode Material, Nagihan Deli̇baş, Turgut Süleymanoğlu Feb 2024

The Effect Of Partial Substitution Of Noble Metal (Pd) At The B Site Of La0.6sr0.4feo3 As A Supercapacitor Electrode Material, Nagihan Deli̇baş, Turgut Süleymanoğlu

Turkish Journal of Chemistry

Sol-gel combustion was used to produce the perovskite-type La0.6Sr0.4FeO3 (LSF) and La0.6Sr0.4Fe0.9Pd0.1O3 (LSFP) materials and assessed as supercapacitor electrodes. The synthesized materials’ crystal structure, morphology, and electrochemical performance were thoroughly analyzed. The partial substitution of Pd in the B site of the LSF structure affected the electrochemical properties of this compound and improved its performance. In fact, the greatest effect of Pd substitution was on the content of oxygen vacancies, which are known as the active sites of the perovskite surface in the supercapacitor cell. The specific capacitance obtained for the sample containing Pd was about 80 F.g–1 at a …

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Detection And Characterization Of The Pichia Manshurica Biofilm On The Traditionally Produced Homemade Apple Vinegar, Zeynep İşlek Koklu, Pınar Akkuş Süt, Esra Eskihoran Üçüncüoğlu, Sadık Kalayci, Fikrettin Şahi̇n Feb 2024

Detection And Characterization Of The Pichia Manshurica Biofilm On The Traditionally Produced Homemade Apple Vinegar, Zeynep İşlek Koklu, Pınar Akkuş Süt, Esra Eskihoran Üçüncüoğlu, Sadık Kalayci, Fikrettin Şahi̇n

Turkish Journal of Chemistry

Pichia yeasts are capable of forming biofilms during vinegar production and causing spoilage in various beverages. In addition, there exists a significant likelihood of encountering yeast contamination which can prevent vinegar production. The present study investigates the detection and characterization of the Pichia manshurica (P. manshurica) biofilm on traditionally produced homemade apple vinegar. The unique characteristics of vinegar were analyzed with a focus on the constituent, known as the “mother of vinegar”, whose composition is comprised of cellulosic biofilm and acetic acid bacteria, including Gluconobacter oxydans (G. oxydans) Briefly, P. manshurica was isolated from apple vinegar and characterized in terms …

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Hydroxyl- Terminated Dendrimers With Sulfonimide Linkers As Binders For Metals Of Industrial Significance, Khaleel Abu Sbeih, Mohammad Al Harahsheh Feb 2024

Hydroxyl- Terminated Dendrimers With Sulfonimide Linkers As Binders For Metals Of Industrial Significance, Khaleel Abu Sbeih, Mohammad Al Harahsheh

Turkish Journal of Chemistry

First- and second-generation hydroxyl- terminated dendrimers were prepared starting from a 1,3-diaminopropane core and sulfonimide linkers. A first-generation mesitylene-derived dendrimer was also prepared with the same terminals. The dendrimers were then reacted with Fe3+, Al3+, and UO22+ separately in order to apply the dendrimers for binding these metals, which have important industrial applications and pose environmental problems simultaneously. The prepared dendrimers were also shown to bind Fe3+ selectively from mixtures with Al3+.

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N-(2-Aminobenzoyl)Benzotriazole Mediated Synthesis Of 3- Acyl-2-Alkyl(Aryl)-4-Hydroxyquinolines And 3-Acylamino-4(3h) Quinazolinones, İlbilge Merve Şenol, Sevtem Gökbulut Satioğlu, İlhami Çeli̇k Feb 2024

N-(2-Aminobenzoyl)Benzotriazole Mediated Synthesis Of 3- Acyl-2-Alkyl(Aryl)-4-Hydroxyquinolines And 3-Acylamino-4(3h) Quinazolinones, İlbilge Merve Şenol, Sevtem Gökbulut Satioğlu, İlhami Çeli̇k

Turkish Journal of Chemistry

New methods have been developed for the synthesis of the substituted quinolines and quinazolinones derivatives by utilizing N-(2-aminobenzoyl)benzotriazoles under mild reaction conditions. 3-Acyl-2-alkyl(aryl)-4-hydroxyquinolines were obtained in modarete yields by the reaction of N-(2-aminobenzoyl)benzotriazoles and diketones in the presence of tert-BuOK. 3-Acylamino-4(3H) quinazolinones were obtained in good yields via N-(2-aminobenzoyl)benzotriazoles, orthoester and hyrazides in one-pot.

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Exploration Of Novel 6,8,9-Trisubstituted Purine Analogues: Synthesis, In Vitro Biological Evaluation, And Their Effect On Human Cancer Cells, Muhammed Fatih Polat, İrem Durmaz Şahi̇n, Rengül Atalay, Meral Tunçbi̇lek Feb 2024

Exploration Of Novel 6,8,9-Trisubstituted Purine Analogues: Synthesis, In Vitro Biological Evaluation, And Their Effect On Human Cancer Cells, Muhammed Fatih Polat, İrem Durmaz Şahi̇n, Rengül Atalay, Meral Tunçbi̇lek

Turkish Journal of Chemistry

Cancer, a leading global cause of mortality, demands continuous advancements in therapeutic strategies. This study focuses on the design and synthesis of a novel series of purine derivatives, specifically 6-(substituted phenyl piperazine)-8-(4-phenoxyphenyl)-9-cyclopentyl purine derivatives (5–11). The motivation behind this endeavor lies in addressing acquired resistance mechanisms in cancer cells, a significant hurdle in current treatment modalities. The synthesis, starting from 4,6-dichloro-5-nitropyrimidine, involves a multi-step process, resulting in seven new purine derivatives. Biological evaluation against human liver, colon, and breast cancer cells (Huh7, HCT116, and MCF7, respectively) was performed using the SRB assay. Among the synthesized analogs, compounds 5 and 6, …

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Copolymerization Of Pyrrole And Carbazole Onto Polyester Textile, Mehmet Akif Küçükkaya, Utku Ustamehmetoğlu, Esma Sezer, Belkıs Ustamehmetoğlu Feb 2024

Copolymerization Of Pyrrole And Carbazole Onto Polyester Textile, Mehmet Akif Küçükkaya, Utku Ustamehmetoğlu, Esma Sezer, Belkıs Ustamehmetoğlu

Turkish Journal of Chemistry

The purpose of this study was the polymerization of carbazole (Cz), pyrrole (Py) and copolymerization of them onto polyester (PES) textile with chemical oxidative method by using FeCl3. First, in order to determine the optimum conditions, the effect of polymerization steps, the immersion order of the PES to the oxidant and monomer solutions, time, monomer, oxidant, and surfactant concentrations and types on the conductivities of PES/PCz composite were investigated and at this conditions, conductive composite, PES/P[Py-co-Cz] was obtained. The highest conductivities were obtained as 12.4 mS/cm and 9.0 mS/cm for PES/PCz and PES/P[Py-co-Cz], respectively. Further characterization of PES/P[Py-co-Cz] was performed …

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Influence Of Convective Heat Transfer Coefficients On Thermal Behaviour Of A Lithium-Ion Cell: A Numerical Study, Uğur Morali Feb 2024

Influence Of Convective Heat Transfer Coefficients On Thermal Behaviour Of A Lithium-Ion Cell: A Numerical Study, Uğur Morali

Turkish Journal of Chemistry

In the current study, the impact of C-ratio, convective heat transfer coefficient, and free stream temperature on the maximal cell temperature and temperature uniformity was computationally and statistically examined. Results revealed that the free stream temperature was the main influential factor for the maximal cell temperature for both natural and forced convection conditions while the C-ratio was the most effective parameter for the temperature uniformity for both natural and forced convections. On the other hand, the contribution of the free stream temperature to the maximum battery temperature increased from 63% to 94% when the conditions were changed from natural convection …

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Palladium (0) Nanoparticles Distributed On Lanthanum (Iii) Oxide As An Effective Catalyst For The Methanolysis Of Hydrazine-Borane To Produce Hydrogen, Adem Rüzgar, Lokman Şener, Yaşar Karataş, Mehmet Gülcan Feb 2024

Palladium (0) Nanoparticles Distributed On Lanthanum (Iii) Oxide As An Effective Catalyst For The Methanolysis Of Hydrazine-Borane To Produce Hydrogen, Adem Rüzgar, Lokman Şener, Yaşar Karataş, Mehmet Gülcan

Turkish Journal of Chemistry

Pd (0) nanoparticles (NPs) distributed on lanthanum (III) oxide were ex situ generated from the reduction of Pd2+ ions using NaBH4 as reducing agent. The Pd/La2O3 displayed good catalytic activity in H2(g) releasing from the hydrazine-borane (HB) methanolysis reaction and it was identified by advanced techniques. Pd/La2O3 was found to be an active catalyst procuring three equiv. H2(g) per mole of HB. The results from TEM images represent the formation of Pd (0) NPs with an average particle size of 1.94 ± 0.1 nm on the surface of La2O3. Moreover, Pd/La2O3 with various Pd loadings were prepared and tested as …

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Nonoxidative Dehydrogenation Of Propane Using Boron-Incorporated Silica-Supported Pt Sites Synthesized By Atomic Layer Deposition, Gokhan Çeli̇k Feb 2024

Nonoxidative Dehydrogenation Of Propane Using Boron-Incorporated Silica-Supported Pt Sites Synthesized By Atomic Layer Deposition, Gokhan Çeli̇k

Turkish Journal of Chemistry

Nonoxidative dehydrogenation of propane to propylene using Pt-based supported catalysts is an active research area in catalysis because catalyst attributes of Pt sites can be controlled by careful design of active sites. One way to achieve this is by the addition of a second metal that may impart a change in the electron density of active sites, which in turn affects catalytic performance. In this study, bimetallic Pt and B sites were deposited on powder SiO2 using atomic layer deposition (ALD). Boron was first deposited on SiO2 via half-cycle ALD using triisoproplyborate as the B source. Following calcination, Pt deposition …

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