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1.
Int J Environ Sci Technol (Tehran) ; 20(2): 1513-1526, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36405244

RESUMO

One of the greatest environmental risks in the cement industry is particulate matter emission (i.e., PM2.5 and PM10). This paper aims to develop descriptive-analytical solutions for increasing the accuracy of predicting particulate matter emissions using resample data of Kerman cement plant. Photometer instruments DUST TRAK and BS-EN-12341 method were used to determine concentration of PM2.5 and PM10. Sampling was performed on 4 environmental stations of Kerman cement plant in the four seasons. In order to accurate assessment of particulate matter concentration, a new model was proposed to resample cement plant time series data using Pandas in Python. The effect of meteorological parameters including wind speed, relative humidity, air temperature and rainfall on the particulate matter concentration was investigated through statistical analysis. The results indicated that the maximum annual average of 24-h of PM2.5 belonged to the east side (opposite the clinker depot) in 2019 (31.50 µg m-3) and west side (in front of the mine) in 2020 (31.00 µg m-3). Also, maximum annual average of 24-h of PM10 belonged to the west side (in front of the mine) in 2020 (121.00 µg m-3) and east side (opposite the clinker depot) in 2020 (120.75 µg m-3). The PM2.5 and PM10 concentrations are more than the allowable limit. The results demonstrate that particulate matter concentration increases with increasing relative humidity and rainfall. Finally, the SARIMA model was used to predict the particulate matter concentration. Supplementary Information: The online version contains supplementary material available at 10.1007/s13762-022-04645-3.

2.
Langmuir ; 38(22): 6911-6922, 2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35611863

RESUMO

Superhydrophobic surfaces (SHSs) and lubricant-infused surfaces (LISs) are two classes of nonwetting surfaces that have drawn attention due to their advanced functional properties including corrosion inhibition. Yet there is a conspicuous lack of corrosion study of SHSs and LISs with respect to their fabrication and material parameters, especially at high temperatures and under dynamic flow conditions over long durations, which is sought to be addressed in this article. Considering copper SHSs and LISs, a full factorial combinatorial study of two facile texturing processes, electrodeposition and etching, two different functionalization agents, stearic acid and mercaptan, and two types of infused lubricants, Krytox 104 and DOWSIL 510, is presented, encompassing over 650 measurements on 90 tested surfaces. All fabricated surfaces demonstrated water repellency with a contact angle above 150° and a sliding angle below 7°. For the first time, the study examines high-temperature corrosion stability and long-term corrosion durability of the nonwetting surfaces in both static fluid and dynamic turbulent flow conditions over a period of 30 days. LISs and SHSs are shown to provide excellent corrosion inhibition over all tested corrosion conditions, with negligible presence of corrosion species on the surfaces and no deterioration of the texturing. The surfaces are also shown to rejuvenate easily to the initial wettability and corrosion resistance values. This study provides valuable insights into the selection of materials and processing parameters for the fabrication of nonwetting surfaces for the application of interest.

3.
J Environ Manage ; 307: 114470, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35085967

RESUMO

A green and resilient (G-Resilient) supply chain network is designed for perishable products under disruption risks and epistemic uncertainties. This study aims to minimize effects of the disruption by presenting new strategies, such as multiple sourcing, financial suppliers, horizontal collaboration, route risk, and coverage radius, in designing a new multi-objective mixed-integer linear programming model for multi-product, multi-period, multi-modal G-Resilient supply chain. Then, a novel robust possibilistic programming (RPP) approach is presented using credibility measure and membership functions of generalized interval-valued type-2 fuzzy variables to face the epistemic uncertainties, such as supply capacity of facilities, customer demand, transportation cost, and CO2 emission factor, in the proposed mathematical model. An improved version of augmented ε-constraint method (AUGMECON2) is also employed to produce separate Pareto-optimal solutions. Moreover, the study compares the proposed RPP with possibilistic chance-constrained programming model and illustrates its advantages; in the standard deviation of CO2 emission objective function, its performance has improved by about 44.91%. Finally, the model's performance has been verified by a real case study in the food industry, and managerial implications have been provided.


Assuntos
Modelos Teóricos , Meios de Transporte , Indústria Alimentícia , Lógica Fuzzy , Probabilidade , Incerteza
4.
Nutr Metab Cardiovasc Dis ; 29(5): 432-439, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30940490

RESUMO

BACKGROUND AND AIM: Given the contradictory results of previous randomized controlled trials (RCTs), we performed a systematic review and meta-analysis to quantify and summarize the effects of folic acid supplementation on C-reactive protein (CRP). METHODS AND RESULTS: We performed a systematic search of all available RCTs conducted up to October 2018 in the following databases: PubMed, Scopus, and Cochrane. RCTs that investigated the effect of folate on CRP were included in the present study. Data were combined with the use of generic inverse-variance random-effects models. Statistical heterogeneity between studies was evaluated using Cochran's Q-test. Ten RCTs (1179 subjects) were included in the present meta-analysis. Pooled analysis results showed that folate supplementation significantly lowered the serum CRP level (weighted mean difference (WMD): -0.685 mg/l, 95% CI: -1.053, -0.318, p < 0.001). However, heterogeneity was significant (I2 = 96.7%, p = 0.000). Stratified analyses indicated that sex, intervention period, and type of study population were sources of heterogeneity. Following analysis, results revealed that the greatest impact was observed in women (WMD: -0.967 mg/l, 95% CI: -1.101, -0.833, p = 0.000), patients with type 2 diabetes mellitus (WMD: -1.764 mg/l, 95% CI: -2.002, -1.526, p = 0.000), and intervention period less than 12 weeks (WMD: -0.742 mg/l, 95% CI: -0.834, -0.650, p = 0.000). CONCLUSION: This meta-analysis suggested that folic acid supplementation could significantly lower the serum CRP level. Folic acid leads to greater CRP lowering effect in women, patients with T2DM, and those with less than 12-week intervention.


Assuntos
Anti-Inflamatórios/administração & dosagem , Proteína C-Reativa/metabolismo , Suplementos Nutricionais , Ácido Fólico/administração & dosagem , Mediadores da Inflamação/sangue , Anti-Inflamatórios/efeitos adversos , Biomarcadores/sangue , Suplementos Nutricionais/efeitos adversos , Regulação para Baixo , Feminino , Ácido Fólico/efeitos adversos , Humanos , Masculino , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
5.
Clin Otolaryngol ; 43(3): 904-911, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29451359

RESUMO

OBJECTIVE: Previous studies have highlighted that narrative skill is critical to the development of the literacy skills by children. Children with cochlear implants (CI) and hearing aids (HA) may have problems in narrative development compared to peers with healthy hearing (HH). There is no exact data about the narrative writing ability of Persian-speaking students who are hearing-impaired. This study was undertaken to compare the microstructure and macrostructure scores for narrative writing of Persian-speaking students who are hearing-impaired and peers with HH. DESIGN: This was a cross-sectional descriptive-analytical study. SETTING: The subjects were recruited from elementary schools in the city of Tehran. PARTICIPANTS: A total of 144 elementary school students were participated. OUTCOME MEASURES: The written narratives were elicited using a wordless pictorial storybook story. Three-way ANOVA with post hoc adjusted Bonferroni test was applied to determine the main effects and interactions of grounded variables on the microstructure and macrostructure components of narrative writing. RESULTS: No significant differences were observed in the macrostructure components of narrative writing between hearing-impaired and HH students. Factors analysis showed that the 4th grade HH students had significantly the highest scores, and the 3rd grade HA students had significantly the lowest scores in microstructure components of narrative writing. CONCLUSION: The findings revealed that hearing-impaired students similarly to their HH peers can transmit the main idea (macrostructure) of narrative writing, but show critical difficulties when using complete grammatical elements (microstructures) to form sentences to convey the idea in the narrative.


Assuntos
Perda Auditiva/psicologia , Desenvolvimento da Linguagem , Narração , Redação , Estudos de Casos e Controles , Criança , Estudos Transversais , Feminino , Humanos , Irã (Geográfico) , Masculino
6.
Opt Lett ; 42(13): 2571-2574, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28957287

RESUMO

We report the fabrication and characterization of Kagome hollow-core antiresonant fibers, which combine low attenuation (as measured at ∼30 cm bend diameter) with a wide operating bandwidth and high modal purity. Record low attenuation values are reported: 12.3 dB/km, 13.9 dB/km, and 9.6 dB/km in three different fibers optimized for operation at 1 µm, 1.55 µm, and 2.5 µm, respectively. These fibers are excellent candidates for ultra-high power delivery at key laser wavelengths including 1.064 µm and 2.94 µm, as well as for applications in gas-based sensing and nonlinear optics.

7.
Anim Genet ; 47(4): 463-70, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26953226

RESUMO

Iranian livestock diversity is still largely unexplored, in spite of the interest in the populations historically reared in this country located near the Fertile Crescent, a major livestock domestication centre. In this investigation, the genetic diversity and differentiation of 10 Iranian indigenous fat-tailed sheep breeds were investigated using 18 microsatellite markers. Iranian breeds were found to host a high level of diversity. This conclusion is substantiated by the large number of alleles observed across loci (average 13.83, range 7-22) and by the high within-breed expected heterozygosity (average 0.75, range 0.72-0.76). Iranian sheep have a low level of genetic differentiation, as indicated by the analysis of molecular variance, which allocated a very small proportion (1.67%) of total variation to the between-population component, and by the small fixation index (FST  = 0.02). Both Bayesian clustering and principal coordinates analysis revealed the absence of a detectable genetic structure. Also, no isolation by distance was observed through comparison of genetic and geographical distances. In spite of high within-breed variation, signatures of inbreeding were detected by the FIS indices, which were positive in all and statistically significant in three breeds. Possible factors explaining the patterns observed, such as considerable gene flow and inbreeding probably due to anthropogenic activities in the light of population management and conservation programmes, are discussed.


Assuntos
Variação Genética , Genética Populacional , Carneiro Doméstico/genética , Alelos , Animais , Teorema de Bayes , Genótipo , Heterozigoto , Endogamia , Irã (Geográfico) , Repetições de Microssatélites
8.
Water Environ Res ; 88(4): 355-66, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27131059

RESUMO

This paper reports tests on a lab-scale surface aeration vessel was equipped with a Rushton turbine to examine its performance in terms of standard aeration efficiency (SAE), mixing time, and void fraction characteristics. These characteristics were investigated by tests using variations of rotor speed, impeller immersion depth, and water level. Results showed that variation of impeller immersion depth had a greater effect on the SAE compared to variation of water level. Moreover, the SAE increased with rotor speeds up to about 150 to 200 rpm and then decreased. In addition, void fraction improved by impeller immersion depth and rotor speed enhancement; however, mixing time and power number were reduced as rotor speed increased. According to the response surface methodology statistical optimizations, optimum values for rotor speed, impeller immersion depth, and water level were 168.90 rpm, 25 mm, and 30 cm, respectively, to achieve the maximum value of SAE.


Assuntos
Reatores Biológicos , Oxigênio/química , Eliminação de Resíduos Líquidos/instrumentação , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Purificação da Água
9.
Prep Biochem Biotechnol ; 46(2): 150-6, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25807048

RESUMO

Growth of Chlorella vulgaris and its lipid production were investigated under autotrophic, heterotrophic, and mixotrophic conditions. Cheap agricultural waste molasses and corn steep liquor from industries were used as carbon and nitrogen sources, respectively. Chlorella vulgaris grew remarkably under this agricultural waste medium, which resulted in a reduction in the final cost of the biodiesel production. Maximum dry weight of 2.62 g L(-1) was obtained in mixotrophic growth with the highest lipid concentration of 0.86 g L(-1). These biomass and lipid concentrations were, respectively, 140% and 170% higher than autotrophic growth and 300% and 1200% higher than heterotrophic growth. In mixotrophic growth, independent or simultaneous occurrence of autotrophic and heterotrophic metabolisms was investigated. The growth of the microalgae was observed to take place first heterotrophically to a minimum substrate concentration with a little fraction in growth under autotrophic metabolism, and then the cells grew more autotrophically. It was found that mixotrophic growth was not a simple combination of heterotrophic and autotrophic growth.


Assuntos
Agricultura , Biotecnologia/métodos , Chlorella vulgaris/crescimento & desenvolvimento , Processos Autotróficos , Biotecnologia/instrumentação , Chlorella vulgaris/metabolismo , Chlorella vulgaris/fisiologia , Meios de Cultura , Processos Heterotróficos , Lipídeos/química , Microalgas/crescimento & desenvolvimento , Microalgas/metabolismo , Pigmentos Biológicos/metabolismo , Saccharum/química , Resíduos , Zea mays/química
10.
Prep Biochem Biotechnol ; 46(4): 368-75, 2016 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-25844976

RESUMO

Chlorella vulgaris (C. vulgaris) microalga was investigated as a new potential feedstock for the production of biodegradable lubricant. In order to enhance microalgae lipid for biolubricant production, mixotrophic growth of C. vulgaris was optimized using statistical analysis of Plackett-Burman (P-B) and response surface methodology (RSM). A cheap substrate-based medium of molasses and corn steep liquor (CSL) was used instead of expensive mineral salts to reduce the total cost of microalgae production. The effects of molasses and CSL concentration (cheap substrates) and light intensity on the growth of microalgae and their lipid content were analyzed and modeled. Designed models by RSM showed good compatibility with a 95% confidence level when compared to the cultivation system. According to the models, optimal cultivation conditions were obtained with biomass productivity of 0.123 g L(-1) day(-1) and lipid dry weight of 0.64 g L(-1) as 35% of dry weight of C. vulgaris. The extracted microalgae lipid presented useful fatty acid for biolubricant production with viscosities of 42.00 cSt at 40°C and 8.500 cSt at 100°C, viscosity index of 185, flash point of 185°C, and pour point of -6°C. These properties showed that microalgae lipid could be used as potential feedstock for biolubricant production.


Assuntos
Lipídeos/química , Microalgas/química , Modelos Biológicos , Biomassa , Meios de Cultura , Microalgas/crescimento & desenvolvimento
11.
Opt Express ; 23(21): 27960-74, 2015 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-26480455

RESUMO

Current optical reflectometric techniques used to characterize optical fibers have to trade-off longitudinal range with spatial resolution and therefore struggle to provide simultaneously wide dynamic range (>20dB) and high resolution (<10cm). In this work, we develop and present a technique we refer to as Optical Side Scattering Radiometry (OSSR) capable of resolving discrete and distributed scattering properties of fibers along their length with up to 60dB dynamic range and 5cm spatial resolution. Our setup is first validated on a standard single mode telecoms fiber. Then we apply it to a record-length 11km hollow core photonic band-gap fiber (HC-PBGF) the characterization requirements of which lie far beyond the capability of standard optical reflectometric instruments. We next demonstrate use of the technique to investigate and explain the unusually high loss observed in another HC-PBGF and finally demonstrate its flexibility by measuring a HC-PBGF operating at a wavelength of 2µm. In all of these examples, good agreement between the OSSR measurements and other well-established (but more limited) characterization methods, i.e. cutback loss and OTDR, was obtained.

12.
Opt Express ; 22(21): 26181-92, 2014 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-25401650

RESUMO

Specialty optical fibers, in particular microstructured and multi-material optical fibers, have complex geometry in terms of structure and/or material composition. Their fabrication, although rapidly developing, is still at a very early stage of development compared with conventional optical fibers. Structural characterization of these fibers during every step of their multi-stage fabrication process is paramount to optimize the fiber-drawing process. The complexity of these fibers restricts the use of conventional refractometry and microscopy techniques to determine their structural and material composition. Here we present, to the best of our knowledge, the first nondestructive structural and material investigation of specialty optical fibers using X-ray computed tomography (CT) methods, not achievable using other techniques. Recent advances in X-ray CT techniques allow the examination of optical fibers and their preforms with sub-micron resolution while preserving the specimen for onward processing and use. In this work, we study some of the most challenging specialty optical fibers and their preforms. We analyze a hollow core photonic band gap fiber and its preforms, and bond quality at the joint between two fusion-spliced hollow core fibers. Additionally, we studied a multi-element optical fiber and a metal incorporated dual suspended-core optical fiber. The application of X-ray CT can be extended to almost all optical fiber types, preforms and devices.


Assuntos
Tecnologia de Fibra Óptica/instrumentação , Fibras Ópticas , Refratometria/instrumentação , Tomografia Computadorizada por Raios X/métodos , Desenho de Equipamento , Fótons
13.
Sci Rep ; 14(1): 7939, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38575741

RESUMO

This study discusses an evacuated tube collector-type solar water heater (ETCSWH) using a phase change material (PCM) chamber with fins, nanofluid, and nano-enhanced phase change material (NEPCM). First, the charging phenomena in a horizontal triplex tube heat exchanger (TTHX) equipped with fins, natural convection, and an ETCSWH system without PCM is simulated to validate the solution. The impact of adding fins and nanoparticles with a volume fraction of 3% of Al2O3 and Cu to paraffin wax and water-based fluid, respectively, on the unit's efficiency has been examined. The proposed system for the PCM melting process, heat storage, fluid flow behavior in the system, and velocity distribution and temperature contour in the storage tank and three parts of the absorber tube have been evaluated using ANSYS FLUENT software in a three-dimensional and transient simulation. The results show that Case 8 has improved by 39.7% compared to Case 1 and Case 4 by 5.2% compared to Case 1 within 4 h of the melting process. Also, Case 8 with a 43% and 6.4% shorter melting time than Cases 1 and 5 has the best performance and the greatest heat transfer rate. The productivity of the ETCSWH system is considerably enhanced by the use of fins, NEPCM, and nanofluid.

14.
J Imaging Inform Med ; 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38844717

RESUMO

Artificial intelligence-enhanced identification of organs, lesions, and other structures in medical imaging is typically done using convolutional neural networks (CNNs) designed to make voxel-accurate segmentations of the region of interest. However, the labels required to train these CNNs are time-consuming to generate and require attention from subject matter experts to ensure quality. For tasks where voxel-level precision is not required, object detection models offer a viable alternative that can reduce annotation effort. Despite this potential application, there are few options for general-purpose object detection frameworks available for 3-D medical imaging. We report on MedYOLO, a 3-D object detection framework using the one-shot detection method of the YOLO family of models and designed for use with medical imaging. We tested this model on four different datasets: BRaTS, LIDC, an abdominal organ Computed tomography (CT) dataset, and an ECG-gated heart CT dataset. We found our models achieve high performance on a diverse range of structures even without hyperparameter tuning, reaching mean average precision (mAP) at intersection over union (IoU) 0.5 of 0.861 on BRaTS, 0.715 on the abdominal CT dataset, and 0.995 on the heart CT dataset. However, the models struggle with some structures, failing to converge on LIDC resulting in a mAP@0.5 of 0.0.

15.
Arch Razi Inst ; 78(6): 1738-1745, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-38828162

RESUMO

Bacteriocins are a kind of antimicrobial peptides that kill or inhibit the growth of bacterial strains. The purpose of this study was to investigate the antibacterial effect of Serratia marcescens on several pathogenic bacterial strains. Bacteriocin produced by S. marcescens was purified by chromatography with Sephadex G-75 column, and its antibacterial effect on gram-negative bacteria, including Escherichia coli ATCC 700928, Pseudomonas aeruginosa PTCC 1707, S. marcescens PTCC 1621, Vibrio fischeri PTCC 1693, and Vibrio harveyi PTCC 1755, were evaluated by the disk diffusion method. The structure of bacteriocin was determined by nuclear magnetic resonance spectroscopy. The interaction of bacteriocin with the antigen 43 (Ag43) of E. coli was evaluated by the molecular docking method. Bacteriocin extracted from bacterial isolates had antibacterial activity on E. coli strains but not on other studied strains. Bioinformatics analysis also showed bacteriocin docking with Ag43 with an energy of -159.968 kJ/mol. Natural compounds, such as bacteriocin, can be an alternative to common chemical compounds and antibiotics. To reach a definite conclusion in this regard, there is a need for further research and understanding of their mechanism of action.


Assuntos
Antibacterianos , Bacteriocinas , Escherichia coli , Serratia marcescens , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/isolamento & purificação , Bacteriocinas/farmacologia , Bacteriocinas/química , Bacteriocinas/isolamento & purificação , Escherichia coli/efeitos dos fármacos , Simulação de Acoplamento Molecular , Serratia marcescens/química
16.
MethodsX ; 10: 102137, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37035525

RESUMO

Solute transport is one of the major topics in geological studies. Fracture is a significant characteristic of natural porous media, where the solute can transport due to its higher density with respect to the density of fluid. As the solute migrates in the medium, the density of the fluid changes with time. In this paper, the mass transport problem in the fractured porous media is modeled using the extended finite element method (X-FEM). An advection-diffusion equation is adopted to define the transport phenomenon in conjunction with the continuity equation of fluid. Transport regimes including diffusion, dispersion and advection are taken into the computational model. The presence of fractures within a porous medium substantially affects the transport behavior. In order to resolve the issue of discontinuity in the field variables, the X-FEM is implemented to discretize the discontinuity of medium. The Newmark integration scheme is adopted to discretize the governing equations in time domain. The nonlinear equations are solved by the Newton-Raphson iterative technique in a fully coupled manner. Finally, in order to illustrate the performance of the proposed computational model, two conventional problems, including the Schincariol problem and the Elder problem as well as the fractured Elder problem are solved numerically. Different patterns of fractures including horizontal and vertical intersecting cracks are adopted to study the effect of fracture density as well as the capability and versatility of the proposed computational model. The method is described in details and the pitfalls of the whole approach are demonstrated. •The density-driven fluid flow in naturally fractured porous media is modeled using an enhanced-FEM technique.•The effect of fractures (faults) in the porous medium is investigated by modeling the transport of saltwater in the fractured Elder problem.•The proposed computational model provides an accurate prediction of subsurface hydrology for a field-scale closed desert basin.

17.
Braz J Biol ; 84: e270680, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36921158

RESUMO

Currently, sweet corn is considered an important crop due to its high sugar content and low starch content. Important sugars in sweet corn include sucrose, fructose, glucose, and maltose. The purpose of the present study was to use the yield indices of the eight examined sweet corn hybrids and the correlation of the yield indices together. Concentration is important for consumers in terms of yield indices. The research site was located at the Látókép Experimental Station of the University of Debrecen. The small plot experiment had a strip plot design with four replications. The previous crop was sweet corn; the plant density was 64 thousand/ha. The obtained result indicates that Biplot AMMI based on IPCA1 showed that the DB, NO, GS, and GB hybrids had stability and high performance in terms of yield indices. At the same time, fructose and glucose had stable parameters for the hybrids involved in the study. IPCA1 AMMI biplot showed that the ME hybrid had stability and high performance in terms of iron and zinc as well. IPCA2 AMMI biplot showed that DE, GB, and GS hybrids had stability and the highest performance on yield parameters in the scope of the research. Fructose, glucose, and sucrose had stable parameters on hybrids based on IPCA2. The DB and SE hybrids had desirable performance in Lutein and Zeaxanthin based on the biplot. The DE hybrid had a maximum performance on iron and zinc parameters.


Assuntos
Zea mays , Glucose , Ferro , Sacarose , Verduras , Zinco
18.
Braz J Biol ; 84: e272093, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37283408

RESUMO

This study aimed to identify the best genotypes using the genotype × yield × trait (GYT) method. To investigate the relationships was performed between yield × traits in four regions of Karaj, Birjand, Shiraz and Arak in two cropping years in a randomized complete block design (RCBD) with three replications. The average grain yield in four regions and two years of the experiment was calculated as 5966 kg/ha, and GYT was obtained based on the multiplication of grain yield with different traits. Comparing the average effect of genotype × year in different environments showed that KSC703 and KSC707 hybrids are among the most productive hybrids among the studied genotypes in grain yield. By examining the correlation coefficients between yield × traits in the tested areas, Y × TWG with Y × GW, Y × NRE, Y × NGR and Y × EL, Y × ED with Y × NGR, Y × NRE with Y × GW and the combination of Y × GW with Y × GL had a positive and significant correlation in all regions. The correlation diagrams were drawn on the evaluated areas' data and showed the correlation of most compounds except Y × GT with each other. Based on the analysis of the main components, the first three components explained the greatest diversity in the population. They were named the component ear grain profile, grain thickness component and plant height profile component.


Assuntos
Grão Comestível , Zea mays , Grão Comestível/genética , Genótipo , Fenótipo , Zea mays/genética
19.
Water Environ Res ; 84(5): 460-72, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22852432

RESUMO

Volatile fatty acids (VFAs) are key intermediates in anaerobic digestion. Enriched acetogenic and methanogenic cultures were used for the syntrophic anaerobic digestion of VFAs in a continuous fixed-bed reactor at mesophilic conditions. The interactive effects of propionic (HPr), butyric (HBu), and acetic (HAc) acids were analyzed. Furthermore, hydraulic retention time (HRT) and methanogen-to-acetogen ratios (M/As) were investigated as the key microbiological and operating variables of VFA anaerobic degradations. Experiments were carried out based on central composite design (CCD) and results were analyzed using response surface methodology (RSM). Effluent concentrations of HPr, HBu, HAc, and biogas production rate (BPR) were directly measured as responses. The optimum conditions were found to be HPr = 1122.9 mg/L, HBu = 1792.4 mg/L, HAc = 1735.4 mg/L, HRT = 21 hours, and M/A = 2.4 (corresponding to the maximum VFA removal and BPR). The results of verification experiments and predicted values from fitted correlations were in close agreement at a 95% confidence interval.


Assuntos
Reatores Biológicos , Ácidos Graxos Voláteis/isolamento & purificação , Ácido Acético/metabolismo , Anaerobiose , Biofilmes , Biocombustíveis , Ácido Butírico/metabolismo , Propionatos/metabolismo
20.
Water Sci Technol ; 66(10): 2229-36, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22949256

RESUMO

Peroxidase from soybean seed coats catalyzes the oxidation and polymerization of aromatic compounds in the presence of H(2)O(2). The present study investigated the optimization of the phenol removal from wastewaters by direct using of soybean seed coats that can be extended to large scale, as a cost-effective option in comparison to pure enzyme. A central composite design was used to evaluate the effect of the following factors on the phenol removal: H(2)O(2) concentration (1-40 mmol/L), polyethylene glycol (PEG) concentration (0-1 g/L) and the amount of soybean seed coats (10-60 g/L). The results showed that PEG concentration had no significant effect on phenol conversion. Additionally, by increasing the amount of soybean seed coats, the extent of phenol conversion was increased and a higher concentration of H(2)O(2) was required to reach the maximum phenol conversion. Under optimum conditions for 1 mmol/L initial phenol, 50 g/L soybean seed coats, 14 mmol/L H(2)O(2) and 0.8 g/L PEG, the phenol conversion after 30 min was 78%. After 2 h, the catalyzed process was capable of achieving 90-92% removal of the total phenol from synthetic wastewater. A cubic model was also developed that was verified by predicting some independent experimental results.


Assuntos
Glycine max/química , Peroxidase/metabolismo , Fenol/química , Sementes/química , Eliminação de Resíduos Líquidos/métodos , Peróxido de Hidrogênio , Peroxidase/química , Fenol/metabolismo , Proteínas de Plantas , Poluentes Químicos da Água/química , Poluentes Químicos da Água/metabolismo
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