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1.
Environ Res ; 224: 115432, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36791837

RESUMO

Uncontrolled emissions, massive price increases, and other factors encourage searching for a suitable diesel engine fuel alternative. In its processed form, vegetable oil biodiesel is an appealing green alternative fuel for compression ignition engines. Vegetable oil esters have qualities comparable to those of standard diesel fuel. As a result, biodiesel may be utilized to run a diesel engine without any further alterations. This article analyses the potential of Phoenix sylvestris oil, which may be found in forest belts across the globe, as a viable feedstock for biodiesel extraction. Phoenix sylvestris oil is found to be abundant in different forest belts worldwide. The free fatty acid must first be transformed into esters using catalytic acid esterification before proceeding to alkaline catalytic esterification. The molar ratio (6:1), catalyst concentration (1 wt%), reaction temperature (60 °C), and reaction time (2 h) have all been optimized for biodiesel extraction. Biodiesel produced had characteristics that were similar to standard biodiesel specifications. The biodiesel yield from Phoenix sylvestris oil was 92.3% under optimum conditions. The experimental results revealed that the Phoenix sylvestris oil biodiesel performed better than neat Phoenix sylvestris oil and its blends. Phoenix sylvestris oil blend produced better brake thermal efficiency with lower smoke, hydrocarbon, and CO emissions. The biodiesel produced from non-edible Phoenix sylvestris oil has the potential to be employed as a viable alternative to diesel fuel.


Assuntos
Biocombustíveis , Gasolina , Gasolina/análise , Biocombustíveis/análise , Emissões de Veículos/análise , Hidrocarbonetos , Óleos de Plantas , Ésteres
2.
3 Biotech ; 11(12): 500, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34881163

RESUMO

Small- and medium-scale farmer's typically follow polyculture or diverse crop cultivation. However, cultivation of diverse crops in small area can cause cross infection leading to disease spreading across crops. A microplot-based field study was conducted to understand the disease susceptibility and disease mobility across various crops, including tomato, chilli, mungbean, and bitter gourd. The mungbean yellow mosaic virus (MYMV) incidence was noted first in the mungbean crop followed by tomato leaf curl New Delhi virus (ToLCNDV) in tomato and chilli leaf curl virus (ChLCV) in chilli crop. Interestingly, bitter gourd crop was infected lastly with symptoms including yellow and green mottling, severe leaf curling, and stunted growth. However, in bitter gourd crop symptoms, like typical leaf curl virus, could not be conclusively related to a certain type of begomovirus. Molecular diagnosis using begomovirus specific deng primers and coat protein (CP) gene primers specific to begomovirus species revealed the presence of ToLCNDV in bitter gourd samples. The phylogenetic analysis of CP gene sequences revealed 98 per cent nucleotide identity with ToLCNDV. Further cross infectivity assays confirmed the transmission of ToLCNDV from tomato to bitter gourd and vice versa. The cryptic species of whiteflies isolated from the bitter gourd fields were sequence confirmed to belong to Asia-I genetic group that were reported to transmit ToLCNDV previously. Overall, our study suggests the vulnerability of bitter gourd crop for ToLCNDV infection when cultivated by the side of tomato plots. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13205-021-02975-6.

3.
Int J Biol Macromol ; 161: 1358-1370, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32750473

RESUMO

In this study, a new natural fiber obtained from the stem of Cissus vitiginea has been studied for the first time. Chemical composition results confirmed that the proposed fiber has a rich amount of cellulose (65.43 wt%) and lower quantity of hemicellulose compounds (14.61 wt%),which in turn leads to better mechanical characteristics. Various chemical groups distributed over the fiber surface were predicted and reported with the help of Fourier transform infrared spectroscope and nuclear magnetic response spectroscopy. The crystalline nature of the fiber surface was examined using X-ray diffraction spectroscopy and the crystallinity index value was calculated to be 30.5% with 12.69 nm crystallite size. Morphological study was conducted on the fiber using a scanning electron microscope. The thermal stability of the fiber was found to be 304 °C with 68.72 kJ/mol kinetic activation energy. Hence C. vitiginea fiber can be suggested as reinforcement for the thermoplastic green composite.


Assuntos
Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Celulose/química , Celulose/isolamento & purificação , Cissus/química , Fibras na Dieta , Extratos Vegetais/química , Fenômenos Químicos , Espectroscopia de Ressonância Magnética , Fenômenos Mecânicos , Compostos Fitoquímicos/química , Casca de Planta/química , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica , Termogravimetria , Difração de Raios X
4.
Phys Chem Chem Phys ; 16(45): 24691-6, 2014 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-25315711

RESUMO

Organic-inorganic hybrid perovskite solar cells with fluorine doped tin oxide/titanium dioxide/CH3NH3PbI3-xClx/poly(3-hexylthiophene)/silver were made in air with more than 50% humidity. The best devices showed an open circuit voltage of 640 mV, a short circuit current density of 18.85 mA cm(-2), a fill factor of 0.407 and a power conversion efficiency of 5.67%. The devices showed external quantum efficiency varying from 60 to 80% over a wavelength region of 350 nm to 750 nm of the solar spectrum. The morphology of the perovskite was investigated using scanning electron microscopy and it was found to be porous in nature. This study provides insights into air-stability of perovskite solar cells.

5.
J Clin Diagn Res ; 8(4): ZC07-10, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24959507

RESUMO

BACKGROUND: Age estimation is an important factor in the identification of an individual in forensic science. The hard tissues of the human dentition are able to resist decay and degradation, long after other tissues are lost. This resistance has made teeth useful indicators for age calculation. Recent research has indicated that Tooth Cementum Annulations (TCA) may be used more reliably than any other morphological or histological traits of the adult skeleton, for age estimation. AIMS: The purpose of this study was to examine the correlation between age and the number of incremental lines in human cementum and to correlate age with thickness of secondary dentin. MATERIALS AND METHODS: The study sample consisted of 100 teeth. Teeth which were extracted because of periodontal disease and orthodontic, and prosthetic reasons were used in the study. The exclusion criterion was teeth with carious lesions. The age of the individuals at the time of tooth extraction ranged from 25-60 years. Longitudinal ground sections of each tooth were prepared and examined. STATISTICAL ANALYSIS: Correlation between estimated age, which was calculated by using cemental lines and thicknes s of secondary dentin and actual age, was found by using Pearson's correlation coefficient. Correlation of increase in thickness of secondary dentin in different age groups was analyzed by ANOVA test. RESULTS: A strong positive correlation was found between the estimated age, which was calculated by using cemental lines and thickness of secondary dentin and actual age. Correlation of increase in thickness of secondary dentin in different age groups was found to be non significant. CONCLUSION: Countable cemental annulations are present in human teeth. Quantification of cementum annuli is a moderately reliable means which is used for age estimation in humans. As the age advances, the thickness of the secondary dentin also increases; hence, the amount of secondary dentin can also be an indicator of age of an individual.

6.
Dent Res J (Isfahan) ; 10(4): 434-9, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24130576

RESUMO

BACKGROUND: Considering the role of matrix metalloproteinase-3 (MMP-3) and tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) in the pathogenesis of periodontitis, the present study is to estimate the levels of MMP-3 and TIMP-1 in gingival crevicular fluid (GCF) in periodontal health, disease and to evaluate the effect of periodontal therapy on MMP-3 and TIMP-1 concentrations in GCF. MATERIALS AND METHODS: A periodontal examination and collection of GCF by extra-crevicular method was performed in 30 subjects selected randomly and categorized into 3 groups. Group I consists of 10 subjects Group II consists of 20 patients and Group III consists of 20 patients of Group II. Non surgical periodontal therapy was performed, and GCF was collected after 8 weeks from the same site of 20 chronic periodontitis patients who are considered as Group III. MMP- 3 and TIMP-1 levels were estimated in GCF-samples by using enzyme-linked immunosorbent assay. The findings were analyzed using the software and descriptive statistical methods such as Mann- Whitney U-test and Kruskal-Wallis test. P value < 0.001 was considered significant. RESULTS: MMP-3 and TIMP-1 was detected in all samples. Highest mean MMP-3 concentrations in GCF were obtained for Group II (7.490 ng/ml) while the lowest concentrations were seen in Group I (0.344 ng/ml) and Group III (2.129 ng/ml). This suggests that MMP-3 levels in GCF increases proportionally with the progression of periodontal disease and decreases after treatment. Lowest mean TIMP-1 concentrations in GCF were obtained for Group-II (1.592 ng/ml), while the highest concentrations were seen in Group-I (8.78 ng/ml) and Group-III (6.40 ng/ml). This suggests that TIMP-1 levels in GCF decreases proportionally with progression of periodontal disease and increases after treatment. CONCLUSION: There is a substantial increase in the concentrations of MMP-3 and decrease in TIMP-1 as periodontal disease progress. Since MMP-3 and TIMP-1 levels in GCF are positively correlated with gingival index, probing pocket depth, and clinical attachment loss, MMP-3, and TIMP-1 may be considered as a Novel Biomarkers in periodontal disease. However, controlled, longitudinal studies are needed to confirm this possibility.

7.
J Indian Soc Periodontol ; 16(4): 549-52, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23493467

RESUMO

BACKGROUND: Initial research has shown a positive correlation between the severity of periodontal disease and matrix metalloproteinase-3 (MMP-3) concentrations in gingival crevicular fluid (GCF). However, there are no enough reports to correlate the MMP-3 concentrations in GCF in periodontal health, disease and after treatment. Hence, the present study is to estimate the levels of MMP-3 in GCF in periodontal health, disease and to evaluate the effect of periodontal therapy on MMP-3 concentrations in GCF. MATERIALS AND METHODS: Periodontal examination and collection of GCF by extracrevicular method was performed in 30 subjects selected randomly and categorized into three groups. Group I (Healthy, n=10), group II (Chronic periodontitis, n=20) and group III (After treatment group, n=20). Scaling and root planing (SRP) was performed and GCF was collected after 8 weeks of treatment. MMP-3 levels were estimated in GCF samples using enzyme linked immunosorbent assay (ELISA). RESULTS: MMP-3 was detected in all samples. Highest mean MMP-3 concentrations in GCF were obtained for group II (7.490 ng/ml), while the lowest concentrations were seen in group I (0.344 ng/ml) and group III (2.129 ng/ml). This suggests that MMP-3 levels in GCF increases proportionally with the progression of periodontal disease and decreases after treatment. CONCLUSION: There is a substantial increase in the concentrations of MMP-3 as periodontal disease progresses. Since MMP-3 levels in GCF are positively correlated with gingival index, probing pocket depth and clinical attachment level, MMP-3 may be considered as a "novel biomarker" in periodontal disease progression. However, controlled, longitudinal studies are needed to confirm this possibility.

8.
Gen Dent ; 59(3): e87-95, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21903535

RESUMO

This study presents case reports of patients with osseous defects who were treated with autogenous bone grafts from the symphysis region, alloplast grafts with barrier membrane, and the use of free gingival onlay grafts for alveolar ridge augmentation. The patients were followed for a period of six months.


Assuntos
Aumento do Rebordo Alveolar/métodos , Adulto , Parafusos Ósseos , Substitutos Ósseos/uso terapêutico , Transplante Ósseo/métodos , Feminino , Seguimentos , Gengiva/transplante , Humanos , Arcada Parcialmente Edêntula/cirurgia , Masculino , Maxila/cirurgia , Membranas Artificiais , Procedimentos Cirúrgicos Pré-Protéticos Bucais , Osteotomia/instrumentação , Osteotomia/métodos , Retalhos Cirúrgicos , Resultado do Tratamento
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