jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Özden KOR | Cengiz KAYACAN
Source: DergiPark (Istanbul University) (article, 2022-01-21)
Field: Materials Science — Materials Chemistry

AN INTERNAL STRUCTURE PROPERTY INVESTİGATİON OF BİNDER JETTİNG ADDİTİVE MANUFACTURİNG PRODUCTS BY BRONZE INFİLTRATİON Bu çalışma, eklemeli imalat yöntemlerinden bağlayıcı püskürtmeli metal eklemeli imalat ile 316L toz malzemesinin iki farklı bağlayıcıya sahip deney numunelerinin mekanik dayanımı ve mikro içyapı incelemesini kapsamaktadır. Bağlayıcı püskürtmeli eklemeli imalat yöntemiyle farklı katman kalınları dikkate alınarak iki farklı bağlayıcının değişen bağlayıcı yüzdeleri ile metal tozlarının serilmesiyle silindirik numuneler imal edilmiştir. Çalışmada kullanılan iki farklı bağlayıcı şu şekildedir. İlk bağlayıcı, Stereolithography (SLA) reçine ve İzo Propil Alkol (IPA) metal tozlar üzerine püskürtülmesi ve Ultraviyole (UV) ışıkla kürlenmesidir. İkinci bağlayıcı ise, Para Toluen Sülfonik Asit (PTSA) metal tozlarıyla karıştırılmış ve üzerine Furfuril Alkol (FA) püskürtülmesiyle metal tozlarının bağlanması sağlanmıştır. Numunelerin ısıl işlem öncesi ve sonrası özkütle ölçümleri yapılmıştır. Mekanik özellikleri belirlenmesi için mikro sertlik ölçümü ve basma testi uygulanmıştır. Elektron mikroskop (SEM) ve optik mikroskop ile numunelerin mikro içyapısı incelenmiştir. Bronze ; Property (philosophy) ; Archaeology ; Ancient history ; Art ; Geography ; History ; Philosophy Metal Alloys Wear and Properties
Authors: Mustapha Bouatia | Aimen El Orche | Amine Cheikh | H Mefetah | Miloud El Karbane | A El Orche | C Adade | A Cheikh | K Karrouchi | M El Karbane | M Bouatia | H Labjar | M Maaouni | M Mbarki | A Mamad | O Elhamdaoui | A Orche | H Bouchafra | M Karbane | A Janoly-Dumenil | S Rochegude | C Chauvet | F Heim | H Constant | J Johnson | M Naiker | M Madakyaru | F Harrou | Y Sun | M Mecozzi | E Sturchio | T Nengsih | F Bertrand | M Maumy-Bertrand | N Meyer | B Zoukeni | (n.D | S Schabrun | L Chipchase | R Wenzel | M Edmond | J Westerhuis | H Hoefsloot | S Smit | D Vis | A Smilde | E Van Velzen | J Van Duijnhoven | F Van Dorsten
Source: Journal of Pharmaceutical Negative Results (article, 2022-01-01)
Field: Chemistry — Analytical Chemistry

Evaluation of FTIR and multivariate data analysis for the control of medical devices Verification of sterilization number of medical devices is one of the main objectives to control its quality and ensure the protection of patients. The objective of this study is to investigate the capability of an automatic tool based on the combination of mid-infrared spectroscopy with a mathematical and statistical algorithm to estimate the number of sterilization cycles of medical pipes. Data analysis is performed by three main methods of pattern recognition: principal component analysis (PCA), support vector learning regression (SVR), and partial least squares regression (PLSR). The result obtained shows high performance capabilities for the prediction of sterilization cycle number. These technologies could be successfully applied in hospitals to ensure the quality of medical devices. Fourier transform infrared spectroscopy ; Multivariate analysis ; Multivariate statistics ; Control (management) ; Computer science ; Statistics ; Mathematics ; Engineering ; Artificial intelligence ; Chemical engineering Spectroscopy and Chemometric Analyses
Authors: Yao Xin
Source: Digital Archive @ GSU (article, 2022-04-12)
Field: Chemistry — Physical and Theoretical Chemistry

Electrokinetic Modeling of Free Solution Electrophoresis Modeling electrophoresis of peptides, proteins, DNA, blood cells and colloids is based on classical electrokinetic theory. The coupled field equations-Poisson, Navier-Stokes or Brinkman, and ion transport equations are solved numerically to calculate the electrophoretic mobilities. First, free solution electrophoretic mobility expressions are derived for weakly charged rigid bead arrays. Variables include the number of beads (N), their size (radius), charge, distribution (configuration), salt type, and salt concentration. We apply these mobility expressions to rings, rigid rods, and wormlike chain models and then apply the approach to the electrophoretic mobilities and translational diffusion constants of weakly charged peptides. It is shown that our bead model can predict the electrophoretic mobilities accurately. In order to make the method applicable at higher salt concentrations and/or to models consisting of larger sized subunits, account is taken of the finite size of the beads making up the model structure. For highly charged particles, it is also necessary to account for ion relaxation. This ion relaxation effect is accounted for by correcting "unrelaxed" mobilities on the basis of model size and average electrostatic surface, or "zeta" potential. With these corrections our model can be applied to the system with absolute electrophoretic mobilities exceeding approximately 0.20 cm2/kV sec and also models involving larger subunits. This includes bead models of duplex DNA. Along somewhat different lines, we have investigated the electrophoresis of colloidal particles with an inner hard core and an outer diffusive layer ("hairy" particles). An electrokinetic gel layer model of a spherical, highly charged colloid particle developed previously, is extended in several ways. The charge of the particle is assumed to arise from the deprotonation of acidic groups that are uniformly distributed over a portion (or all) of the gel layer. Free energy considerations coupled with Poisson-Boltzmann theory is used to calculate the change of the local pKa of the acidic groups depending on the local electrostatic environment. Based on the modeling of electrophoresis and viscosity, we predict that the thickness of the gel layer decreases as the salt concentration increases. And only the outermost portion of the gel layer is charged. Electrokinetic phenomena ; Electrophoresis ; Electrophoretic light scattering ; Chemistry ; Zeta potential ; Hydrodynamic radius ; Diffusion ; Colloid ; Chemical physics ; Surface charge ; Relaxation (psychology) ; Analytical Chemistry (journal) ; Chromatography ; Materials science ; Thermodynamics ; Aqueous solution ; Dynamic light scattering ; Nanotechnology ; Micelle ; Nanoparticle ; Physics ; Physical chemistry Electrostatics and Colloid Interactions ; Microfluidic and Capillary Electrophoresis Applications ; Nanopore and Nanochannel Transport Studies
Authors: M. Merced Montero‐Campillo | Otília Mó | Manuel Yáñez
Source: Sci (article, 2022-02-13)
Field: Chemistry — Physical and Theoretical Chemistry

Malonaldehyde-like Systems: BeF2 Clusters—A Subtle Balance between Hydrogen Bonds, Beryllium Bonds, and Resonance The stability of malonaldehyde is governed by intramolecular hydrogen bonds (IMHBs) as well as in malonaldehyde-like systems where oxygen is replaced by N or S at any of the basic sites. As beryllium bonds have been shown to strongly cooperate with hydrogen bonds, this work explores at the high level ab initio G4 level of theory the effect of including this non-covalent interaction in the system through its association with BeF2. Although malonaldehyde follows the expected trends, where the formation of a pseudocyclic form is favored also when IMHB and Be bonds are present, the subtle balance between both non-covalent interactions leads to some surprising results when other heteroatoms are involved, to the point that interaction energies can be much larger than expected or even cyclization is not favored. A complete analysis using different computational tools gives an answer to those cases escaping the predictable trends. Hydrogen bond ; Chemistry ; Covalent bond ; Intramolecular force ; Heteroatom ; Beryllium ; Computational chemistry ; Resonance (particle physics) ; Chemical physics ; Crystallography ; Molecule ; Stereochemistry ; Ring (chemistry) ; Atomic physics ; Organic chemistry ; Physics Crystallography and molecular interactions ; Advanced Chemical Physics Studies ; Molecular Spectroscopy and Structure
Authors: Güray Kılınççeker | Farhad Zarifi
Source: Eurasian Journal of Biological and Chemical Sciences (article, 2022-12-21)
Field: Chemistry — Inorganic Chemistry

Perilen bazlı serin pigmentlerin moleküler dinamik simulasyonu ve NIR bölgesinin yansımasında yapısal özelliklerin incelenmesi Güneş ışığının etkisini azaltan özel boyalarda kullanılan serin pigmentler genellikle perilenler yardımıyla üretilir. Beyaz boyalar güneş ışığını geniş bir yelpazede yansıtırken, siyah ve diğer koyu renkler geniş bir spektrumu absorbe ettikleri için uygulandıkları malzemelerin ısınmasına etki ederler. “Serin pigmentler” (boyalar) olarak adlandırılan moleküller, koyu renkli olmalarına rağmen güneş ışınlarının NIR bölgesinde çok düşük absorpsiyon göstermeleri nedeniyle ilgi görmektedir. Bu çalışmada, 12 farklı perilen bazlı pigment kuantum hesaplamaları ile analiz edilmiş, yansımaları ve özellikleri arasındaki korelasyonlar incelenmiştir. Hesaplamalarda Hartree-Fock hesaplama yöntemi ve 3-21G temel seti kullanılarak Gaussian 9 Revision D.01 de yapılmıştır. Yardımcı ara yüzey yazılımı olarak Gaussview 5.0.8 kullanılmıştır. Sentezlenen perilenlerin karakterizasyonu Ft-IR, NMR, XRD ile yapılmış ve daha önceki çalışmalarda yayınlanmıştır. Simülasyondan elde edilen entalpi, HOMO.LUMO aralığı, simetri ve dipol momentleri karşılaştırılmış ve sonuç olarak NIR yansımasının pigmentlerin dipol momentleri ile ilişkili olduğu tespit edilmiştir. Physics ; Nuclear chemistry ; Chemistry ; Stereochemistry Pigment Synthesis and Properties ; Dyeing and Modifying Textile Fibers ; Transition Metal Oxide Nanomaterials
Authors: Y. Doğan Daldal | Ebru Demıralay
Source: Afyon Kocatepe University Journal of Sciences and Engineering (article, 2022-10-27)
Field: Chemistry — Spectroscopy

Determination of Thermodynamic Protonation Constants of Some Selective Serotonin Reuptake Inhibitors in Water-Acetonitrile Binary Mixtures Bu çalışmada, trisiklik antidepresanlara alternatif olarak kullanılan selektif serotonin geri alım inhibitörleri (SSRİ)’nden sitalopram, fluvoksamin ve sertralinin su-asetonitril ikili karışımında, ters faz sıvı kromatografik (RPLC) yöntemle alıkonma davranışı incelenmiştir. Kromatografik analizler, mobil faz pH’sı 6,5 ila 10,5 arasında değişen, %45-%55 (h/h) arasında asetonitril içeren asetonitril-su ikili karışımlarında gerçekleştirilmiştir. Çalışma boyunca, kolon sıcaklığı ve akış hızı sırasıyla, 30 oC ve 0,8 mL/dakika’da sabitlenmiştir. Bu çalışmada, mobil faz pH değerlerine karşı bileşiklerin alıkonma değerlerinin lineer solvasyon enerjisi ilişkisi (LSER) yaklaşımıyla değerlendirilmesiyle teorik alıkonma değerleri hesaplanmıştır. Ayrıca farklı pH değerlerindeki mobil fazların aktivite katsayıları değerleri hesaba katılarak doğrusal olmayan regresyon programıyla bileşiklerin termodinamik protonasyon sabitleri ((_s^s)〖pK〗_a) belirlenmiştir. Hidrofobik özellikteki bileşiklerin (_s^s)〖pK〗_a değerleri kullanılarak iki farklı yaklaşımla su ortamındaki protonasyon sabiti değerleri hesaplanmıştır. Çalışma sonunda her iki ekstrapolasyon yönteminden elde edilen sonuçların birbiriyle uyumlu olduğu görülmüştür. Protonation ; Chemistry ; Acetonitrile ; Nuclear chemistry ; Chromatography ; Medicinal chemistry ; Mathematics ; Organic chemistry Analytical Chemistry and Chromatography ; Analytical Methods in Pharmaceuticals ; Thermodynamic properties of mixtures
Authors: Chinar Mustafa Mohammed
Source: Advances in Animal and Veterinary Sciences (article, 2022-01-01)
Field: Chemistry — Analytical Chemistry

Cardio-protective Effects of Bradykinin and Tetraethyleamonium on the Arrhythmia Induced by Barium Chloride in Male Rat A cute myocardial ischemia and infarction are frequent- ly the outcomes of the underlying etiology, coronary artery blockage (AMI) which is a notable cause of death in developed nations The identification of a possible "cardio-safe" new chemical entity (NCE) depends heavily on cardiac electrophysiology in the animal model as well as in vitro and silico studies It is well known that the infusion of BaCl 2 promotes the development of arrhythmia by causing prolonged depolarization and triggering activity via rises in Na + and Ca 2+ influx to the heart. The presence of K + in the external solution may be impeded by the penetration of Ba 2+ through the K + channel, which could increase the auto-rhythmicity of the heart and result in ventricular arrhythmia, according to electrophysiological investigations. This is the most important finding The therapeutic advantages of nonapeptide BK have been demonstrated in several clinical and experimental trials, and they extend beyond the treatment of hypertension and congestive heart failure Since BK circulates at extremely low concentrations (1 to 50 fmol/mL) and is quickly digested by kininases, research Barium chloride ; Bradykinin ; Barium ; Chemistry ; Internal medicine ; Pharmacology ; Anesthesia ; Endocrinology ; Medicine ; Inorganic chemistry ; Receptor Analytical Methods in Pharmaceuticals ; Renal function and acid-base balance ; Vitamin K Research Studies
Authors: Kedan He | Djenerly G. Massena
Source: Research Square (preprint, 2022-09-07)
Field: Chemistry — Analytical Chemistry

Unsupervised Ensemble Learning Using High-dimensional Spectroscopy Data of Organic Compounds Abstract Cluster ensemble (CE) is an ensemble learning strategy for unsupervised learning (clustering) that uses a set of clustering solutions to achieve more comprehensive clustering results than traditional single clustering approaches. This meta-learning formalism helps users overcome the dilemma of choosing the appropriate clustering algorithm and parameters for a given data set. Unfortunately, not all clustering solutions in the ensemble contribute to the final data partition. Cluster ensemble selection (CES) aims at selecting a subset from a large library of clustering solutions to form a smaller cluster ensemble that performs as well as or better than the set of all available clustering solutions. In this paper, we investigate four CES methods for the categorization of structurally distinct organic compounds using high-dimensional IR and Raman spectroscopy data. Single quality selection (SQI) forms a subset of the ensemble by selecting the highest quality ensemble members. The Single Quality Selection (SQI) method is used with various quality indices to select subsets by including the highest quality ensemble members. The Bagging method, usually applied in supervised learning, ranks ensemble members by calculating the normalized mutual information (NMI) between ensemble members and consensus solutions generated from a randomly sampled subset of the full ensemble. The hierarchical cluster and select method (HCAS-SQI) uses the diversity matrix of ensemble members to select a diverse set of ensemble members with the highest quality. Furthermore, a combining strategy can be used to combine subsets selected using multiple quality indices (HCAS-MQI) for the refinement of clustering solutions in the ensemble. The IR + Raman hybrid ensemble library is created by merging two complementary “views” of the organic compounds. This inherently more diverse library gives the best full ensemble consensus results. Overall, the Bagging method is recommended because it provides the most robust results that are better than or comparable to the full ensemble consensus solutions. Cluster analysis ; Ensemble learning ; Computer science ; Consensus clustering ; Data mining ; Artificial intelligence ; Pattern recognition (psychology) ; Machine learning ; Ensemble forecasting ; Correlation clustering ; CURE data clustering algorithm Spectroscopy and Chemometric Analyses ; Advanced Chemical Sensor Technologies ; Advanced Clustering Algorithms Research
Authors: Utary Nur Rachmani Fauzan | Astrinida Rizkina Dwi Pancani | Fitria Yulistiani | Nancy Siti Djenar
Source: Jurnal Kimia Riset (article, 2022-06-30)
Field: Chemistry — Inorganic Chemistry

UTILIZATION OF ANTHOCYANIN IN EDIBLE FILM AS COCONUT MILK FRESHNESS INDICATOR Technology in smart packaging continues to evolve, one of which is packages equipped with food freshness indicators to monitor food safety and quality. These indicators can be formed by immobilizing anthocyanin into edible film and then changing its color to pH changes. The research aims to determine the immobilization time, test the color stability of the edible film indicator to temperature changes, determine the characterizations of the edible film indicator based on the %relative standard deviation (%RSD) value, and apply the edible film indicators as coconut milk freshness indicators. The best immobilization time was in the 90th minute with %RSD=0%. The edible film indicators did not change color from 10 to 50°C with %RSD=0%. The characterizations of edible film indicators on pH 6, 7, 8, and 10 had response times of 6.68 minutes; 9.49 minutes; 3.57 minutes; and 4.37 minutes; periods of 14 days, 13 days, 14 days, and 16 days; and good reproducibility at pH 6 and 10 and not good at pH 7 and 8. Overall, based on anthocyanin color changes, an edible film indicator can be used as a freshness indicator in coconut milk but cannot indicate the pH value of coconut milk. Anthocyanin ; Food science ; Chemistry ; Relative standard deviation ; Liquid food ; Mathematics ; Pulp and paper industry ; Chromatography Coconut Research and Applications ; Food and Agricultural Sciences
Authors: Y. Doğan Daldal | Ebru Demıralay
Source: DergiPark (Istanbul University) (article, 2022-06-04)
Field: Chemistry — Physical and Theoretical Chemistry

Bazı Selektif Serotonin Geri Alım İnhibitörlerinin Termodinamik Protonasyon Sabitlerinin Su-Asetonitril İkili Karışımlarında Belirlenmesi Bu çalışmada, trisiklik antidepresanlara alternatif olarak kullanılan selektif serotonin geri alım inhibitörleri (SSRİ)’nden sitalopram, fluvoksamin ve sertralinin su-asetonitril ikili karışımında, ters faz sıvı kromatografik (RPLC) yöntemle alıkonma davranışı incelenmiştir. Kromatografik analizler, mobil faz pH’sı 6,5 ila 10,5 arasında değişen, %45-%55 (h/h) arasında asetonitril içeren asetonitril-su ikili karışımlarında gerçekleştirilmiştir. Çalışma boyunca, kolon sıcaklığı ve akış hızı sırasıyla, 30 oC ve 0,8 mL/dakika’da sabitlenmiştir. Bu çalışmada, mobil faz pH değerlerine karşı bileşiklerin alıkonma değerlerinin lineer solvasyon enerjisi ilişkisi (LSER) yaklaşımıyla değerlendirilmesiyle teorik alıkonma değerleri hesaplanmıştır. Ayrıca farklı pH değerlerindeki mobil fazların aktivite katsayıları değerleri hesaba katılarak doğrusal olmayan regresyon programıyla bileşiklerin termodinamik protonasyon sabitleri ((_s^s)〖pK〗_a) belirlenmiştir. Hidrofobik özellikteki bileşiklerin (_s^s)〖pK〗_a değerleri kullanılarak iki farklı yaklaşımla su ortamındaki protonasyon sabiti değerleri hesaplanmıştır. Çalışma sonunda her iki ekstrapolasyon yönteminden elde edilen sonuçların birbiriyle uyumlu olduğu görülmüştür. Psychology Various Chemistry Research Topics
Authors: Sri Agustina | Ramayanty Bulan | Agustami Sitorus
Source: Computer Science and Information Technologies (article, 2022-11-01)
Field: Chemistry — Analytical Chemistry

Prediction of mango firmness by near infrared spectroscopy tandem with machine learning The firmness of the mango fruit is one of the internal physical properties that can show its quality. Unfortunately, non-destructive methods to measure this are not yet available. In the current study, we develop a calibration model using near infrared spectroscopy to predict the physical properties (firmness) of the mango cultivar Arumanis (Mangifera indica cv. Arumanis) via machine learning. Spectral data were acquired using the fourier transform near-infrared (FTNIR) benchtop with a wavelength range of 1000 to 2500 nm. Multivariate spectra analysis based on machine learning, including principal component regression (PCR), partial least squares regression (PLSR), and support vector machine regression (SVMR), was utilized and compared to estimate the firmness of fresh mangos. The results obtained show that the prediction of machine learning by PLSR is better than that of SVMR and PCR for the prediction of mango firmness. The coefficient correlation of calibration (rc) and validation (rcv), the root means square error of calibration (RMSE-C) and validation (RMSE-CV), and the ratio of prediction to deviation (RPD) were 0.941, 0.382 kgf, 0.920, 0.472 kgf, and 2.556, respectively. The general results satisfactorily indicate that near infrared spectroscopy technology integrated with an appropriate machine learning algorithm has optimistic results in determining the firmness of mango non-destructively. Tandem ; Infrared spectroscopy ; Infrared ; Spectroscopy ; Materials science ; Computer science ; Chemistry ; Composite material ; Optics ; Physics Spectroscopy and Chemometric Analyses ; Spectroscopy Techniques in Biomedical and Chemical Research ; Smart Agriculture and AI
Authors: Shibang Ma | Guo Ailing | Xing Wang
Source: Journal of Engineering Science and Technology Review (article, 2022-01-01)
Field: Chemistry — Analytical Chemistry

Comprehensive Identification of Beef Freshness with Multi-index Using Visible/Near-Infrared Spectroscopy Freshness is an important quality attribute that affects the quality and safety of meat. Spectral technology has been widely used to detect the attributes of agricultural products. However, the selected freshness indexes and the accuracy of prediction models are the main factors that affect their practical application. Visible (Vis)-near-infrared (NIR) (Vis-NIR) spectroscopy with multi-index was used to realize the rapid and nondestructive detection of beef freshness and improve the accuracy of prediction. The laboratory Vis-NIR spectroscopy system was constructed to collect the reflectance spectrum range of 400-1700 nm of 56 beef samples stored 4 C for 1-17 days. The changes in the physical and chemical indexes of beef color, total volatile basic nitrogen (TVB-N), pH value, and total bacterial count with time were studied, and which could be taken as the indexes for the comprehensive assessment of beef freshness was studied. The different spectrum pretreatment methods and prediction models of indexes were investigated. Results reveal that the five indexes of meat color (L * for bright index, a * for green and red), TVB-N, pH value, and total bacterial count are taken as indexes to evaluate beef freshness. The linear discriminant analysis (LDA) model refers to the comprehensive identification model of beef freshness. The best spectrum pretreatment methods and spectral prediction models of the five indexes are determined. The correlation coefficients of the five aforementioned indexes' prediction model in the verification set are 0.900, 0.890, 0.862, 0.902, and 0.875, and their standard deviations are 2.025, 3.027, 0.183, 7.502 mg(100g) -1 , and 0.447 logCFUg -1 , respectively. The multi-index comprehensive identification LDA model of beef freshness is verified, and its discriminating rate is verified for 100%. The proposed algorithm provides evidences for the further development of the device for the rapid and nondestructive determination of beef freshness. Identification (biology) ; Index (typography) ; Spectroscopy ; Infrared spectroscopy ; Infrared ; Materials science ; Analytical Chemistry (journal) ; Chemistry ; Computer science ; Chromatography ; Optics ; Physics ; World Wide Web ; Organic chemistry ; Biology ; Botany Spectroscopy and Chemometric Analyses ; Water Quality Monitoring and Analysis