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Split gauge-boson mass in SU(N)×SU(M)theories
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作者 Julia Gómez Concejo Felipe J.Llanes-Estrada +1 位作者 Diego María-Almazán Alexandre Salas-Bernárdez 《Communications in Theoretical Physics》 2025年第9期61-71,共11页
We extend a well-known mass-gap equation for pure gluodynamics in global colour models(formulated in equal-time quantization in Coulomb gauge)to one in which gluons are split into two sets,each exhibiting different ma... We extend a well-known mass-gap equation for pure gluodynamics in global colour models(formulated in equal-time quantization in Coulomb gauge)to one in which gluons are split into two sets,each exhibiting different masses.If the theory is SU(N)×SU(M)with gluons in both groups having identical couplings(as suggested by Grand Unification arguments at large scales)it is immediate to see that different masses are generated for each subgroup.This global symmetry is not broken,but the split masses erase accidental symmetries that might be present due to the two couplings being the same at a large scale,such as SU(N×M)or similar.We also numerically explore a couple of low-dimensional examples of simple Lie groups,but in spite of the system of equations having a form that would seem to allow spontaneous symmetry breaking,it is not triggered for these groups whose algebra has no ideal,and the dispersion relations for the various gluons converge to the same form. 展开更多
关键词 global symmetry breaking gap equation CHROMODYNAMICS hamiltonian QCD
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Soil resilience assessment using soil profile descriptions and Analytic Hierarchy Process in Mediterranean mountains considering diverse fire occurrences
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作者 Jesús RODRIGO-COMINO 《Journal of Mountain Science》 SCIE CSCD 2024年第8期2517-2532,共16页
Wildfires are complex natural phenomena that exert significant impacts on landscapes,societies,and economies.Understanding the concept of resilience is crucial in mitigating its possible negative impacts,as it involve... Wildfires are complex natural phenomena that exert significant impacts on landscapes,societies,and economies.Understanding the concept of resilience is crucial in mitigating its possible negative impacts,as it involves preparing for,responding to,and recovering from wildfires.This research aims to demonstrate the utility of in situ soil profile description in assessing land use resilience using an Analytic Hierarchy Process(AHP)through an expert panel survey.The study examines a catchment located in the Balearic Islands,considering two fire occurrences(once and twice),comparing abandoned agricultural terraces and natural hillslopes.The results demonstrated that the priority ranking of variables to assess soil profile resilience against wildfires,determined by a panel of 10 experts,identified horizon depth(25.1%),slope inclination(21.5%),and hydrological connectivity(16.6%)as the most crucial factors.Other variables,such as number and size of roots,structure of pedal soil material,size class structure,and rock fragments,also contributed to resilience but to a lesser extent,with scores ranging from 5.7%to 9.6%.Analyzing the priorities established by the experts using AHP,the results showed that the least resilient soil horizon was H1 of the control hillslope,especially under high and low connectivity processes,which aligned with the loss of superficial soil horizons after one and two wildfires.Hillslopes showed greater changes in resilience after occurring wildfires compared to terraces,with the most significant alterations occurring after the second wildfire event.This study addresses a significant knowledge gap in the field by highlighting the interconnectedness of wildfires,resilience,and land use,providing insights into land management strategies for wildfire-prone regions. 展开更多
关键词 Soil profiles Soil geography WILDFIRES AHP Land management Expert panel survey
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Single atom Cu-N-C catalysts for the electro-reduction of CO_(2) to CO assessed by rotating ring-disc electrode
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作者 S.Pérez-Rodríguez M.Gutiérrez-Roa +6 位作者 C.Giménez-Rubio D.Ríos-Ruiz P.Arévalo-Cid M.V.Martínez-Huerta A.Zitolo M.J.Lázaro D.Sebastián 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期169-182,I0004,共15页
The electrochemical CO_(2) reduction reaction(CO_(2)RR) to controllable chemicals is considered as a promising pathway to store intermittent renewable energy. Herein, a set of catalysts based on copper-nitrogendoped c... The electrochemical CO_(2) reduction reaction(CO_(2)RR) to controllable chemicals is considered as a promising pathway to store intermittent renewable energy. Herein, a set of catalysts based on copper-nitrogendoped carbon xerogel(Cu-N-C) are successfully developed varying the copper amount and the nature of the copper precursor, for the efficient CO_(2)RR. The electrocatalytic performance of Cu-N-C materials is assessed by a rotating ring-disc electrode(RRDE), technique still rarely explored for CO_(2)RR. For comparison, products are also characterized by online gas chromatography in a H-cell. The as-synthesized Cu-NC catalysts are found to be active and highly CO selective at low overpotentials(from -0.6 to -0.8 V vs.RHE) in 0.1 M KHCO_(3), while H_(2) from the competitive water reduction appears at larger overpotentials(-0.9 V vs. RHE). The optimum copper acetate-derived catalyst containing Cu-N_(4) moieties exhibits a CO_(2)-to-CO turnover frequency of 997 h^(-1) at -0.9 V vs. RHE with a H_(2)/CO ratio of 1.8. These results demonstrate that RRDE configuration can be used as a feasible approach for identifying electrolysis products from CO_(2)RR. 展开更多
关键词 Cu-N-C Carbon xerogel Rotating ring disc electrode Carbon dioxide reduction reaction Carbon monoxide
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Isothermal hydrogen absorption process of Pd-capped Mg films traced by ion beam techniques and optical methods
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作者 D.Abejón P.Prieto +6 位作者 J.K.Kim A.Redondo-Cubero M.L.Crespillo F.Leardini I.J.Ferrer G.García J.R.Ares 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第9期3675-3684,共10页
Pd-capped nanocrystalline Mg films were prepared by electron beam evaporation and hydrogenated under isothermal conditions to inves-tigate the hydrogen absorption process via ion beam techniques and in situ optical me... Pd-capped nanocrystalline Mg films were prepared by electron beam evaporation and hydrogenated under isothermal conditions to inves-tigate the hydrogen absorption process via ion beam techniques and in situ optical methods.Films were characterized by different techniques such as X-ray diffraction(XRD)and scanning electron microscopy(SEM).Rutherford backscattering spectrometry(RBS)and elastic recoil detection analysis(ERDA)provided a detailed compositional depth profile of the films during hydrogenation.Gas-solid reaction kinetics theory applied to ERDA data revealed a H absorption mechanism controlled by H diffusion.This rate-limiting step was also confirmed by XRD measurements.The diffusion coefficient(D)was also determined via RBS and ERDA,with a value of(1.1±0.1)·10^(−13)cm^(2)/s at 140℃.Results confirm the validity of IBA to monitor the hydrogenation process and to extract the control mechanism of the process.The H kinetic information given by optical methods is strongly influenced by the optical absorption of the magnesium layer,revealing that thinner films are needed to extract further and reliable information from that technique. 展开更多
关键词 Magnesium hydride Hydrogen absorption Ion beam techniques Optical tracing Absorption mechanism
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Heart Failure Registries in Asia-What Have We Learned?
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作者 Jayagopal Pathiyil Balagopalan Jabir Abdullakutty 《Cardiovascular Innovations and Applications》 2024年第1期516-528,共13页
Heart Failure(HF)is one of the leading problems in cardiology practice today.Acute decompensated heart failure(ADHF)is a significant cause of mortality and morbidity worldwide,and this is more relevant in the Asian su... Heart Failure(HF)is one of the leading problems in cardiology practice today.Acute decompensated heart failure(ADHF)is a significant cause of mortality and morbidity worldwide,and this is more relevant in the Asian subcontinent with a high population burden.Various regional registries in Asia have given us valuable insight into the aetiology and outcomes in this context.Though there are regional differences,it is clear from the review carried out in this paper that HF affects a much younger population.The comorbidities like diabetes and hypertension are high.Chronic kidney disease and atrial fibrillation are higher compared to the Western cohort.Heart failure with preserved ejection fraction is less often seen.The in-hospital mortality ranges from 2.8%to 8.4%.The one-year mortality is higher,and re-hospitalization is very high.Though in many Asian countries,guideline-directed medical therapy is initiated in hospitals,adherence is low.This is the challenge,and the way forward is only a practical team-based heart failure treatment approach.In the modern-day world of digital technology,the onus is on us to develop an integrated system of care in HF.This is by using available resources and opening up HF clinics.This review compares the strengths and limitations of various heart failure registries conducted in Asia and also gives a direction to plan effective strategies for improving heart failure care. 展开更多
关键词 Heart failure Asian HF registry Acute Decompensated Heart failure Heart Failure Registry
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The Beneficial Effects of Components of Garlic (Allium sativum L.) in the Poultry Industry
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作者 Alejandra Meza-Rios Gilberto Velazquez-Juarez +9 位作者 Inkar Castellanos-Huerta Rocio Ivette Lopez-Roa Luis A. Anguiano-Sevilla Xochitl Hernanez-Velasco Xochitl Hernanez-Velasco Saeed El-Ashram Ebtsam Al-Olayan Billy Hargis Guillermo Tellez-Isaias Adelaida Sara Minia Zepeda-Morales 《Food and Nutrition Sciences》 CAS 2024年第1期27-57,共31页
Plant-based antimicrobial agents are readily available, cost-effective, and exhibit low toxicity, making them promising alternatives in combatting microbial infections. Among these plants, garlic (Allium sativum) stan... Plant-based antimicrobial agents are readily available, cost-effective, and exhibit low toxicity, making them promising alternatives in combatting microbial infections. Among these plants, garlic (Allium sativum) stands out for its traditional medicinal use in effectively combating various microorganisms. In the poultry industry, preventing avian virus and bacterial infections is paramount for chicken husbandry. However, using conventional drugs poses potential risks to human health. Garlic, a widely used Asian plant in traditional medicine for various pathologies, has shown potential as an herbal prophylactic remedy against viral and bacterial infections. Recently, researchers explored garlic and its derivatives as a scientific strategy in veterinary practices for diverse purposes, such as improving poultry production characteristics and acting as antibiotic growth promoters. This comprehensive review delves into garlic and its derivatives as preventive and corrective treatments for viral diseases in laying hens and broilers. The paper highlights their potential effectiveness and safety as a natural means to enhance poultry health and welfare while mitigating the risks associated with conventional drug usage in the food industry. 展开更多
关键词 GARLIC ANTIVIRAL VETERINARY CHICKENS Allium sativum
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Telomerase activity in colorectal cancer,prognostic factor and implications in the microsatellite instability pathway 被引量:8
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作者 M Vidaurreta ML Maestro +4 位作者 S Rafael S Veganzones MT Sanz-Casla J Cerdán M Arroyo 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第28期3868-3872,共5页
AIM: To determine whether the telomerase activity is related to the Microsatellite instability (MSI) genetic pathway and whether it means a difference in the survival.METHODS: The population consisted of 97 colore... AIM: To determine whether the telomerase activity is related to the Microsatellite instability (MSI) genetic pathway and whether it means a difference in the survival.METHODS: The population consisted of 97 colorectal cancer patients. MSI determination was performed in accordance with the NCI criteria using PCR and Genescan. Telomerase activity was determined by the TRAP-assay, an ELISA procedure based on the amplification of telomeric repeat sequences.RESULTS: 6.2% showed high MSI (MSI-H), 10.3% showed low MSI (MSI-L) and 83.5% did not show this alteration (MSS). Positive telomerase activity was detected in 92.8% of the patients. 83.3% of MSI-H tumors showed positive telomerase against 93.8% of MSS tumors. In the overall survival analysis the absence of telomerase activity conferred a better prognosis.CONCLUSION: Previous works have shown that tumors which develop via the MSI pathway present a better prognosis. No link between telomerase activity and MSl status is observed, although sample sizes are small. Patients with telomerase negative tumors had better overall survival than patients with telomerase positive tumors. 展开更多
关键词 Microsatellite instability TELOMERASE Colorectal cancer PROGNOSIS
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Recent progress on bimetallic NiCo and CoFe based electrocatalysts for alkaline oxygen evolution reaction: A review 被引量:7
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作者 Gebrehiwet Abrham Gebreslase Maria Victoria Martínez-Huerta Maria Jesus Lázaro 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第4期101-137,共37页
The deployment of hydrogen as an energy carrier is found to be a vital alternative fuel for the future. It is expected that water electrolysis, powered by renewable energy sources, be able to scale-up hydrogen product... The deployment of hydrogen as an energy carrier is found to be a vital alternative fuel for the future. It is expected that water electrolysis, powered by renewable energy sources, be able to scale-up hydrogen production. However, the reaction kinetic of oxygen evolution reaction(OER) is a sluggish process, which predominantly limits the efficiency of water electrolysis. This review recapitulates the recent progress and efforts made in the design and development of two selected earth-abundant bimetallic electrocatalysts(Ni Co and Co Fe) for alkaline OER. Each bimetal electrocatalyst is thoroughly outlined and discussed in five sub-sections, including bimetal(oxy) hydroxides, Layered double hydroxides(LDHs) structures,oxides, composites, alloy and nanostructured electrocatalysts, and assembled with heteroatoms.Furthermore, a brief introduction to an in situ/operando characterization techniques and advantages for monitoring the structure of the electrocatalysts is provided. Finally, a summary outlining the challenges and conceivable approaches to advance OER performance is highlighted and discussed. 展开更多
关键词 Water electrolysis Oxygen evolution reaction Bimetallic electrocatalyst Nickel Cobalt and iron
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CONTROLLABILITY AND OPTIMALITY OF LINEAR TIME-INVARIANT NEUTRAL CONTROL SYSTEMS WITH DIFFERENT FRACTIONAL ORDERS 被引量:3
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作者 丁小丽 Juan J.NIETO 《Acta Mathematica Scientia》 SCIE CSCD 2015年第5期1003-1013,共11页
Control systems governed by linear time-invariant neutral equations with different fractional orders are considered. Sufficient and necessary conditions for the controllability of those systems are established. The ex... Control systems governed by linear time-invariant neutral equations with different fractional orders are considered. Sufficient and necessary conditions for the controllability of those systems are established. The existence of optimal controls for the systems is given. Finally, two examples are provided to show the application of our results. 展开更多
关键词 CONTROLLABILITY OPTIMALITY neutral equations different fractional orders
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Supporting IrO2 and IrRuOx nanoparticles on TiO2 and Nb-doped TiO2 nanotubes as electrocatalysts for the oxygen evolution reaction 被引量:3
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作者 Radostina V.Genova-Koleva Francisco Alcaide +4 位作者 Garbine Alvarez Pere L.Cabot Hans-Jürgen Grande María V.Martínez-Huerta Oscar Miguel 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第7期227-239,共13页
IrO2 and IrRuOx(Ir:Ru 60:40 at%),supported by 50 wt%onto titania nanotubes(TNTs)and(3 at%Nb)Nb-doped titania nanotubes(Nb-TNTs),as electrocatalysts for the oxygen evolution reaction(OER),were synthesized and character... IrO2 and IrRuOx(Ir:Ru 60:40 at%),supported by 50 wt%onto titania nanotubes(TNTs)and(3 at%Nb)Nb-doped titania nanotubes(Nb-TNTs),as electrocatalysts for the oxygen evolution reaction(OER),were synthesized and characterized by means of structural,surface analytical and electrochemical techniques.Nb doping of titania significantly increased the surface area of the support from 145(TNTs)to 260 m2g-1(Nb-TNTs),which was significantly higher than those of the Nb-doped titania supports previously reported in the literature.The surface analytical techniques showed good dispersion of the catalysts onto the supports.The X-ray photoelectron spectroscopy analyses showed that Nb was mainly in the form of Nb(IV)species,the suitable form to behave as a donor introducing free electrons to the conduction band of titania.The redox transitions of the cyclic voltammograms,in agreement with the XPS results,were found to be reversible.Despite the supported materials presented bigger crystallite sizes than the unsupported ones,the total number of active sites of the former was also higher due to their better catalyst dispersion.Considering the outer and the total charges of the cyclic voltammograms in the range 0.1–1.4 V,stability and electrode potentials at given current densities,the preferred catalyst was Ir O2 supported on the Nb-TNTs.The electrode potentials corresponding to given current densities were between the smallest ones given in the literature despite the small oxide loading used in this work and its Nb doping,thus making the Nb-TNTs-supported IrO2 catalyst a promising candidate for the OER.The good dispersion of IrO2,high specific surface area of the Nb-doped supports,accessibility of the electroactive centers,increased stability due to Nb doping and electron donor properties of the Nb(IV)oxide species were considered the main reasons for its good performance. 展开更多
关键词 Nb-doped TIO2 NANOTUBES IrO2 CATALYST IrRuOx CATALYST Oxygen evolution reaction PEMWE
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Reagent-free determination of amikacin content in amikacin sulfate injections by FTIR derivative spectroscopy in a continuous flow system 被引量:1
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作者 José F.Ovalles Máximo Gallignani +2 位作者 María R.Brunetto Rebeca A.Rondón Carlos Ayala 《Journal of Pharmaceutical Analysis》 SCIE CAS 2014年第2期125-131,共7页
The quantitative estimation of amikacin (AMK) in AMK sulfate injection samples is reported using FTIR-derivative spectrometric method in a continuous flow system. Fourier transform of mid-IR spectra were recorded wi... The quantitative estimation of amikacin (AMK) in AMK sulfate injection samples is reported using FTIR-derivative spectrometric method in a continuous flow system. Fourier transform of mid-IR spectra were recorded without any sample pretreatment. A good linear calibration (r40.999, %RSDo 2.0) in the range of 7.7-77.0 mg/mL was found. The results showed a good correlation with the manufacturer's and overall they all fell within acceptable limits of most pharmacopoeial monographs on AMK sulfate. 展开更多
关键词 AMIKACIN FlrIR derivative spectro-metry Continuous flow system Pharmaceuticalpreparation INJECTION SULFATE
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Exergy Analysis of a Double-Effect Solar Absorption Refrigeration System in Ngaoundere 被引量:2
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作者 Maurice Tenkeng Paiguy Armand Ngouateu Wouagfack Réné Tchinda 《World Journal of Engineering and Technology》 2019年第1期158-174,共17页
Solar energy is replacing more and more traditional sources of energy because of the fact that it’s also fighting about global warming. This study is based on exergy analysis of a double-effect series flow absorption... Solar energy is replacing more and more traditional sources of energy because of the fact that it’s also fighting about global warming. This study is based on exergy analysis of a double-effect series flow absorption refrigeration system powered by solar energy in Ngaoundere. The simulation is done on the basis of a half hourly analysis for the first time, from 6.30 AM to 6.30 PM, using water-lithium bromide as working pair. The main parameters for the performance of an absorption cycle, which are the COP and the ECOP, have been analyzed and the results show that this two parameters increase while increasing the temperature of the main generator. The exergy loss of each component of the system and the total exergy loss of the system have been analyzed and their effectiveness calculated, using the first and second law of thermodynamics. The highest exergy loss occurs in the main generator GI and in the absorber, making these components more important in an absorption cycle. This analysis is based on a mathematical model using FORTRAN?language. The results obtained may be useful for the optimization of solar absorption refrigeration systems. 展开更多
关键词 DOUBLE Effect REFRIGERATION HALF Hourly EXERGY LOSS
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Reduction of NO by CO using Pd–CeTb and Pd–CeZr catalysts supported on SiO_2 and La_2O_3–Al_2O_3 被引量:7
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作者 Victor Ferrer Dora Finol +2 位作者 Roger Solano Alexander Moronta Miguel Ramos 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2015年第1期87-96,共10页
The catalytic activity of Pd catalysts supported on Ce0.73Tb0.27Ox/SiO2, Ce0.6Zr0.4Ox/Si O2,Ce0.73Tb0.27Ox/La2O3–Al2O3and Ce0.6Zr0.4Ox/La2O3–Al2O3was studied using the reduction of NO by CO. The catalysts were chara... The catalytic activity of Pd catalysts supported on Ce0.73Tb0.27Ox/SiO2, Ce0.6Zr0.4Ox/Si O2,Ce0.73Tb0.27Ox/La2O3–Al2O3and Ce0.6Zr0.4Ox/La2O3–Al2O3was studied using the reduction of NO by CO. The catalysts were characterized by X-ray fluorescence, surface area, X-ray diffraction, temperature-programmed reduction, CO chemisorption and oxygen storage capacity. Temperature-programmed reduction results indicated that Tb or Zr incorporation improves the reducibility and oxygen storage capacity. CO chemisorption data suggested the presence of large Pd O particles due to the low CO/Pd ratio. No significant differences were obtained in light off temperatures(T Light off) for all Pd catalysts and the most active was1.5%Pd/Ce0.6Zr0.4Ox/SiO2. 展开更多
关键词 Mixed oxides OSC Reduction of NO by CO Three way catalysts
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Energy Analysis and Exergy Utilization in the Residential Sector of Cameroon 被引量:1
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作者 Talla Konchou Franck Armel Aloyem Kazé Claude Vidal Tchinda René 《Energy and Power Engineering》 2015年第3期93-104,共12页
In this paper, we present an analysis of energy and exergy utilization in the residential sector of Cameroon by considering the sectoral energy and exergy flows for the years of 2001-2010. Exergy analysis of Cameroon ... In this paper, we present an analysis of energy and exergy utilization in the residential sector of Cameroon by considering the sectoral energy and exergy flows for the years of 2001-2010. Exergy analysis of Cameroon residential sector utilisation indicates a less efficient picture than that obtained by the energy analysis. Cooking stands out as the most inefficient end use in the Cameroon’s residential sector. In 2010, the energy and exergy efficiency are determined and were respectively 58.74% and 22.63%. Energy and exergy flows diagrams for the overall efficiencies of Cameroon residential sector are illustrated and a comparison with the residential sector of other countries is also done. To carry out this study, a survey of 250 households was conducted and the sharing of the end uses of energy was done and data were gathered. 展开更多
关键词 EXERGY EFFICIENCY Energy FLOW RESIDENTIAL SECTOR
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Use of Graphene and Cucurbit[7]uril Electrodes for the Determination of Amantadine in Biological Fluids 被引量:2
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作者 C. S. H. Domínguez P. Hernández 《American Journal of Analytical Chemistry》 2015年第7期623-630,共8页
A differential pulse voltammetry (DPV) method for amantadine (AT) determination is developed. To this end, all the chemical and instrumental variables affecting the determination of amantadine are optimized. These stu... A differential pulse voltammetry (DPV) method for amantadine (AT) determination is developed. To this end, all the chemical and instrumental variables affecting the determination of amantadine are optimized. These studies have used three types of glassy-carbon electrode, first electrode which has not undergone surface modification or coating, to then modify the working electrode surface with two kinds of suspensions: graphene and graphene-cucurbit[7]uril (CB[7]). From studies of the mechanisms governing the electrochemical response of amantadine, it was concluded that it is an electrochemically system with a diffusive reduction phenomenon. Under optimal conditions and with the appropriate electrode modification, we proceed to study the relation between the peak intensity with the analyte concentration. Thus, we find that when the electrode surface is covered with graphene-CB[7], two linear sections are obtained, the first one in the concentration range of between 0.05 μg·mL﹣1 and 0.75 μg·mL﹣1;and the second one between 1.00 μg·mL﹣1 and 6.00 μg·mL﹣1, with Er (%) = 87 and R.S.D. = 0.94% (n = 10 at 0.5 μg·mL﹣1 level). The minimum detectable amount was 15 ng·mL﹣1 while a concentration of 44 ng·mL﹣1 was calculated as determination limit. The optimized method was applied to the determination of amantadine in biological fluids. 展开更多
关键词 GLASSY-CARBON Electrode AMANTADINE Differential Pulse VOLTAMMETRY Human URINE
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Mersenne Numbers, Recursive Generation of Natural Numbers, and Counting the Number of Prime Numbers 被引量:1
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作者 Ramon Carbó-Dorca 《Applied Mathematics》 2022年第6期538-543,共6页
A simple recursive algorithm to generate the set of natural numbers, based on Mersenne numbers: M<sub>N</sub> = 2<sup>N</sup> – 1, is used to count the number of prime numbers within the preci... A simple recursive algorithm to generate the set of natural numbers, based on Mersenne numbers: M<sub>N</sub> = 2<sup>N</sup> – 1, is used to count the number of prime numbers within the precise Mersenne natural number intervals: [0;M<sub>N</sub>]. This permits the formulation of an extended twin prime conjecture. Moreover, it is found that the prime numbers subsets contained in Mersenne intervals have cardinalities strongly correlated with the corresponding Mersenne numbers. 展开更多
关键词 Mersenne Numbers Recursive Generation of Natural Numbers Mersenne Natural Number Intervals Counting the Number of Prime Numbers in Mersenne Natural Intervals Correlation between Prime Number Set Cardinalities and Mersenne Numbers Extended Twin Prime Number Conjecture
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Stability Estimation for Markov Control Processes with Discounted Cost 被引量:1
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作者 Jaime Eduardo Martínez-Sánchez 《Applied Mathematics》 2020年第6期491-509,共19页
This article explores controllable Borel spaces, stationary, homogeneous Markov processes, discrete time with infinite horizon, with bounded cost functions and using the expected total discounted cost criterion. The p... This article explores controllable Borel spaces, stationary, homogeneous Markov processes, discrete time with infinite horizon, with bounded cost functions and using the expected total discounted cost criterion. The problem of the estimation of stability for this type of process is set. The central objective is to obtain a bounded stability index expressed in terms of the Lévy-Prokhorov metric;likewise, sufficient conditions are provided for the existence of such inequalities. 展开更多
关键词 Discrete-Time Markov Control Process Expected Total Discounted Cost Stability Index Probabilistic Metric Lévy-Prokhorov Metric
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Electrical Power Losses in a Photovoltaic Solar Cell Operating under Partial Shading Conditions 被引量:1
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作者 Abdouramani Dadjé Noel Djongyang Réné Tchinda 《Journal of Power and Energy Engineering》 2017年第10期19-33,共15页
The aim of this paper is to determine the power losses recorded by a PV generator operating under partial shading conditions. These losses are evaluated through two distinct methods. The first method is based on mathe... The aim of this paper is to determine the power losses recorded by a PV generator operating under partial shading conditions. These losses are evaluated through two distinct methods. The first method is based on mathematical modeling, while the second is based on Simulink’s physical model. The losses recorded are considerable and increase as a function of the increase in the percentage of shading up to a limit value where they become constant in the case where an ideal by-pass diode is connected in parallel with the modules. This limit value is non-existent in the case where the bypass diode is not ideal, which in fact corresponds to the real model. However, it emerges that the power losses are minimized in a PV system comprising bypass diodes, in particular in the case where the partial shading is considerable. 展开更多
关键词 Electrical Power Losses PV Generator Partial Shading Conditions Mathematical Modeling Simulink’s Physical Model
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New approaches to identification and characterization of tioconazole in raw material and in pharmaceutical dosage forms 被引量:1
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作者 Natalia L.Calvo Vera A.Alvarez +1 位作者 María C.Lamas Darío Leonardi 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2019年第1期40-48,共9页
Tioconazole(TCZ), a broad-spectrum antifungal agent, has significant activity against Candida albicans and other Candida species, and therefore, it is indicated for the topical treatment of superficial mycoses.The mai... Tioconazole(TCZ), a broad-spectrum antifungal agent, has significant activity against Candida albicans and other Candida species, and therefore, it is indicated for the topical treatment of superficial mycoses.The main goal of this work is to report an exhaustive identification and characterization procedure to improve and facilitate the online quality control and continuous process monitoring of TCZ in bulk material and loaded in two different dosage forms: ovules and nail lacquer. The methodologies were based on thermal(differential scanning calorimetry(DSC), melting point, and thermogravimetry(TG)),spectroscopic(ultraviolet(UV), Raman, near infrared(NIR), infrared spectroscopy coupled to attenuated total reflectance(FTIR-ATR), and nuclear magnetic resonance(NMR)), microscopic and X-ray diffraction(XRD). The TCZ bulk powder showed a high crystallinity, as observed by XRD, with a particles size distribution(3–95 mm) resolved by microscopic measurements. TCZ melting point(82.8 °C) and a degradation peak centered at 297.8 °C were obtained by DSC and DTG, respectively. An unambiguous structure elucidation of TCZ was obtained by mono-and two-dimensional1 H and13 C NMR spectral data analysis. The FTIR-ATR, Raman and NIR spectra of both the raw material and the commercial products were analyzed and their characteristic bands were tabulated. The best methods for TCZ identification in ovules were DSC, TG, XRD, NIR and Raman, while NIR and FTIR-ATR were the most appropriate techniques to analyze it in the nail lacquer. DSC, TG, DRX, Raman, FTIR-ATR and NIR spectroscopy are effective techniques to be used in online process analysis, because they do not require sample preparation, and they are considerably sensitive to analyze complex samples. 展开更多
关键词 Tioconazole IDENTIFICATION CHARACTERIZATION PHARMACEUTICAL DOSAGE FORMS SPECTROSCOPIC methods
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Assessing vegetation community distribution characteristics and succession stages in mountainous areas hosting coming Winter Olympics Games 被引量:1
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作者 ZHANG Heng-shuo ZHA Tong-gang +2 位作者 YU Yang JI Xiao-dong JESÚS Rodrigo-Comino 《Journal of Mountain Science》 SCIE CSCD 2021年第11期2870-2887,共18页
Alpine mountain ecosystem shows strong interactions between abiotic and biotic parameters.They also receive high attention from human activities(natural tourism,trekking,skiing,etc.).However,as the potential disturban... Alpine mountain ecosystem shows strong interactions between abiotic and biotic parameters.They also receive high attention from human activities(natural tourism,trekking,skiing,etc.).However,as the potential disturbance risk areas in alpine mountains are increasing,it is necessary to understand the relationship between environmental factors and plant communities.This is also the key consideration for the coming international events such as the Winter Olympic Games,which could generate uncontrolled ecosystem issues not previously studied.The Yin Mountains in Chongli district,Zhangjiakou City,Hebei Province,China will be the core area of the 2022 Winter Olympic Games.We hypothesize that disturbances will be caused,therefore,the previous relationships between the habitat factors and plant community and the main environmental limiting factors before hosting them must be assessed to design future restoration plans.Therefore,we used the two-way indicator species analysis(TWINSPAN)and market basket analysis(MBA)for vegetation classification in 91 sampling plots.Plant community and relationships among environmental variables(altitude,slope position,aspect,direction,inclination,soil porosity,soil bulk density,organic matter content and soil pH)were investigated through the trend correspondence(DCA)and canonical correspondence analyses(CCA).Also,the TWINSPAN was used to classify the vegetation into 6 different groups.CCA analysis showed that i)the spatial variation of soil moisture and the content of soil organic matter are the main factors limiting the development of shrub and herb communities;ii)the distribution of different forest communities was mainly affected by terrain factors(altitude,aspect and slope position);iii)the dynamic changes of vegetation communities in different altitudes were affected by the fluctuation of environmental factors and human disturbance,and the shrubs and herbaceous plants in mid-to-high altitude areas(above 1400 m)generally show the process of transformation from the pioneer community to transitional community in the competition.We concluded that under the strong interference of human activities in the core construction area of the Olympic venues,higher damage intensity and lower resilience in the low altitude area is observed compared with the pioneer community.Whereas in the low altitude area(below 1400m)with a fragile ecological environment,although the plant diversity and coverage are poor,the potential impact and damage degree of the Olympic Games are greatly reduced due to the distance from the construction area of the core venues and good resilience.This information can help land managers and policymakers to anticipate human disturbances on plant communities and support guiding the most efficient ecological restoration after the Winter Olympic Games in 2022. 展开更多
关键词 Vegetation classification Topographic factors Community distribution Winter Olympic Games
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