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21.
The usage of ultrasound has gained popularity in the recent years. Ultrasonic processing means blasting liquids, usually water, with very intense sound at high frequency, producing very well mixed powerful chemical and physical reactions. This paper deals with the investigation of the effect of ultrasonic energy on the conversion fraction of sulfur in the production reaction of sodium thiosulfate which was obtained from sulfur and Na2SO3 solution. Concentration of Na2SO3 solution parameter was chosen as the constant parameter. The experiments were performed with various amplitudes of ultrasound power and in the absence and presence of ultrasound energy in various temperatures with various particle sizes. The results indicate that the conversion fraction values increase in the presence of ultrasound energy and increase at high amplitude values.  相似文献   
22.
BACKGROUND: Mechanization of Rosa damascena flower harvest is limited because of the asynchronous flowering period, the necessity for the harvest operation to take place in the early hour of the morning, and a lack of knowledge regarding the physical–mechanical properties of R. damascena. This study investigated the effect of harvesting hour on some physical–mechanical properties of R. damascena. RESULTS: The terminal velocity of the rose flower ranged from 4.00 to 2.38 m s?1. The highest picking force was found to be 6.29 N for the harvesting hour of 06:00 am. Tear forces of petal changed from 1.54 to 0.97 N for the harvesting hour of 06:00 am and 12:00 pm, respectively. The tension force of pedicel varied between 8.25 and 7.76 N. The weight of the rose flower was measured as an average of 1.61 and 1.50 g at 06:00 am and 12:00 pm, respectively. Horizontal and vertical projection areas of rose flowers were positively correlated with harvesting hour, with an R2 of 0.97 and 0.75, respectively. Results showed that there was a minor loss in colour for both inner and outer surfaces of petals. CONCLUSION: The results of physical–mechanical properties of R. damascena obtained from this study should be considered for the operation of flower harvest mechanization. Copyright © 2011 Society of Chemical Industry  相似文献   
23.
The adsorption process is largely a surface-action phenomenon. In this study, sorption capacities for heavy metals on a solid waste matrix were investigated. Five heavy metals (iron, copper, zinc, nickel and cadmium) were chosen because of their availability in any landfill site. The conditions during all the experimental runs were pH 7.0, temperature 32 degrees C and suppressed microbial degradation. For adsorption isotherm (Freundlich and Langmuir) calculations, fixed quantities of heavy metal ions were mixed with variable quantities of solid waste. The ratio of mass of adsorbate per unit mass of adsorbent was changed five times, by changing only the adsorbent amount. The results showed that the time required to reach equilibrium varied from metal to metal but all reached equilibrium within the first 32 h. The relative potential of sorption of the individual metals and mixed metals on the solid waste matrix is Fe > Zn > Cu > Ni > Cd. The sorption capacity of domestic solid waste matrix for heavy metals is quite significant and this property might prove helpful for the in situ removal of heavy metals in landfill operation.  相似文献   
24.
The present study is insight into pollen morphology for characterizing species and their utility in the taxonomic separation of certain taxa of subfamily Nepetoideae (Lamiaceae) from Pakistan. The pollen micromorphology of 11 species of the Nepetoideae was analyzed and documented using light microscopy and scanning electron microscopy (SEM) for both qualitative and quantitative characteristics. Most species have hexazonocolpate pollen grains but trizonocolpate and tetrazonocolpate pollen with circular and oval amb were also rarely observed in Mentha spicata. The basic pollen shape in most of the studied species was subspheroidal but prolate grains were also observed in M. spicata, S. coccinea, and S. plebeia. The exine sculpturing of Nepetoideae pollen was taxonomically very informative particularly at subfamily level. Observations of exine sculpturing with SEM revealed various types of pollen grains: reticulate, bireticulate, microreticulate, perforate, aerolate, and gammate. The bireticulate type further subdivided into three subtypes based on the number of secondary lumina in each primary lumen and is characterized by varying characteristics of the secondary reticulum and primary muri. A significant variation was observed in colpus surface ornamentation. The maximum polar diameter was found in O. americanum (58 ± 5.8 μm) and the maximum equatorial diameter observed in O. basilicum (50.25 ± 1.37 μm). Pollen features of the studied species were discussed and compared based on the current taxonomical concepts. The results showed that pollen traits of the subfamily Nepetoideae was found significant to classify the taxa. Furthermore, pollen features provide additional evidence to distinguish macromorphologically similar taxa from each other.  相似文献   
25.
In present study, multiple microscope techniques were used for the systematics identification of the species Asplenium dalhousiae. The plant was collected from different phytogeographical and its natural habitat of Pakistan, where it shows higher diversity. Morphology, foliar epidermal anatomy, and spore morphological characters of the species were studied in detailed using multiple microscopic techniques through light microscopy (LM) and scanning electron microscopy (SEM). LM and SEM were used for the systematics identification of the species. Traditionally, the species is used in the ailment of many diseases, so the spore morphology, anatomical features, and morphological characters are relevant to describe the species taxonomy. The importance of multiple methods of taxonomic study (e.g., documentation and morphological characteristics) for characterizing herbs are important step in systematic certification to maintain the efficacy of herbal medicines. The aim of the present study is to examine the morphological, anatomical, and spore morphology of the species A. dalhousiae in more detailed for the correct taxonomic identification and their medicinal validation from Pakistan.  相似文献   
26.
Iris L. is one of the important genus of family Iridaceae, consist of 56 taxa naturally occurred in Turkey. The similarities and variations in the subgenus overlapping the taxonomic positions of the species in the subgenera and needs anatomical assessment especially by microscopic techniques. In this study, the taxonomic significance of leaf anatomical characters of 10 Iris subgenus Scorpiris taxa were studied in detail and the relationship among these taxa were evaluated using microscopy techniques. Fresh leaf samples of species were fixed in 70% alcohol solution for anatomical observation under microscope. Eleven different micromorphological features were statistically analyzed to delimit the species in subgenus. Based on morphological and anatomical similarities, we studied relationships among; (1) ssp. turcica, ssp. caucasica, I. nezahatiae and I. pseudocaucasica; (2) correlation between ssp. turcica and ssp. caucasica; (3) association of I. galatica, I. persica, ssp. margaretiae and ssp. stenophylla with each other; (4) relationship between ssp. stenophylla and ssp. margaretiae; and (5) relevance between I. aucheri and I. peshmeniana. Moreover, the taxonomy of subgenus Scorpiris has been discussed in detail with novel and diagnostic features based on micromorphological physiognomies. We found that four species in this study are endemic to Turkey, while seven are critically endangered geophytes in the country. The leaf anatomical characteristics of 10 taxa were divided into three groups. Main aim of this research was to study the taxonomy of the complex subgenus Scorpiris through microscopic techniques.  相似文献   
27.
Foliar and stem epidermal anatomical features of the tribe Cynoglosseae have been studied in detail for the taxonomic identification using light microscopy (LM) and scanning electron microscopic (SEM) techniques. A comparative study was conducted on different plant parts (leaf and stem epidermal anatomy) of 25 species belonging to eight genera of the tribe Cynoglosseae (Boraginaceae) collected from different phytogeographical regions of Iran for the first time. Different qualitative and quantitative characteristics were observed in detail using LM and SEM. Results showed that although generally the stem and leaf anatomical traits were similar, but some diagnostic features were examined for distinguishing the closely related genera in the tribe. The ratio of cortex/diameter of stem and phloem/xylem, the average row number of collenchyma, palisade and spongy cells, structure of trichomes, type of indumentum and palisade arrangement were found taxonomically important. The anatomical characters were statistically analyzed using cluster analysis and principal component analysis. The study found that stem and leaf eccentrics are variable in the genus but constant within species of the same genus. Most species had typical isobilateral leaves, but some showed an incipient dorsoventrally symmetry with a layer of abaxial palisade tissue. Eglandular trichomes were observed found in all the studied species, which were recognized based on structure and function. In present study some novel characters have been observed which are of great interest to the taxonomist for the correct identification some genera delimitations. The characters studied here are of less taxonomic value and delimitating at species level.  相似文献   
28.
In this decade, the use of nano particles (NPs) against bacterial growth is increasing day by day due to remarkable alternative properties compared to molecular antibiotics. Thus, the use of iron oxide nanoparticles (IONPs) has proven one of the most important transition metals oxide‐based remedy in nanotechnological advances and biological applications due to enriched biocompatibility of iron. In this study synthesis of IONPs was carried out via co‐precipitation method. The crystallographic morphology of the synthesized particles was studied via X‐ray diffraction which revealed cubic structure of the particles, whereas, the spinal shaped morphology of the prepared NPs was confirmed from scanning electron microscopy. Likewise, the presence of the major elements in the sample was determined through energy dispersive X‐ray analysis characterization. Bactericidal effect of the NPs was assessed at pre‐defined concentrations (50 and 100 μg/ml) against Gram +ve bacteria Staphylococcus aureus, Gram ?ve bacteria Shigella dysentry and Escherichia coli . Bacterial strains, which demonstrate the potential of NPs. The purpose of this study was assessing the structure of the synthesized NPs for protective effect against harmful bacterial activity.  相似文献   
29.
Spore morphology of Thelypteridaceae species growing in Malakand Division, Northern Pakistan, was studied using both light microscopy and scanning electron microscopy. The taxa are Christella dentata and Glaphyropteridopsis erubescens in the subfamily Thelypteridoideae, and Phegopteris connectilis, Pseudophegopteris pyrrhorhachis, and Pseudophegopteris levingei in the subfamily Phegopteridoideae. The studied species exhibit differences in spore size, exospore thickness, color, and ornamentation. Spores of the studied species are monolete and medium‐sized, and shape is ellipsoidal in both polar and equatorial views. The average measurement of the polar diameter ranges from 27 μm to 31 μm, whereas in the equatorial direction it varied from 20 μm to 40 μm. The exospore thickness ranges from 1.2 μm to 2.4 μm. Reticulate, laevigate with microgranules, cristate, and coarsely echinate surface ornamentation are observed among the species. Multivariate analysis including unweighted pair group method with arithmetic mean and principal component analysis was used for the grouping and discrimination of species and genera.  相似文献   
30.
The International Journal of Advanced Manufacturing Technology - Beside machining condition and parameters, coating properties is one of the main factors affecting tool performance and wear...  相似文献   
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