scholarly journals The Development of the Cuticular Wax Layer in Prune Plums and the Changes Occurring in it During Drying

1969 ◽  
Vol 22 (1) ◽  
pp. 101 ◽  
Author(s):  
Joan M Bain ◽  
D Mcg Mcbean

The development of the wax layer or bloom has been observed on prune plums throughout the growing season (177 days), using the carbon replica and thin�sectioning techniques of electron microscopy. Changes in their average fresh weight, surface area, percentage of total and soluble solids, and the amount of wax per fruit and per square centimetre were determined also at 12 intervals during their growth.

1967 ◽  
Vol 20 (5) ◽  
pp. 895 ◽  
Author(s):  
Joan M Bain ◽  
D Mcg Mcbean

Wax on the surface of prune plums, sampled from 2 weeks before fruit was mature until 2 weeks after, was shown by electron microscopy, using the carbon� replica technique, to occur in a two-layer structure. The iruier layer consisted of a matrix of thin platelets, while the outer layer was composed of fragile projections, many of which appeared tubular. The incidence and complexity of the projections in the outer layer increased as the fruit matured.


Author(s):  
J.R. Walton

In electron microscopy, lead is the metal most widely used for enhancing specimen contrast. Lead citrate requires a pH of 12 to stain thin sections of epoxy-embedded material rapidly and intensively. However, this high alkalinity tends to leach out enzyme reaction products, making lead citrate unsuitable for many cytochemical studies. Substitution of the chelator aspartate for citrate allows staining to be carried out at pH 6 or 7 without apparent effect on cytochemical products. Moreover, due to the low, controlled level of free lead ions, contamination-free staining can be carried out en bloc, prior to dehydration and embedding. En bloc use of lead aspartate permits the grid-staining step to be bypassed, allowing samples to be examined immediately after thin-sectioning.Procedures. To prevent precipitation of lead salts, double- or glass-distilled H20 used in the stain and rinses should be boiled to drive off carbon dioxide and glassware should be carefully rinsed to remove any persisting traces of calcium ion.


Author(s):  
J. L. Farrant ◽  
J. D. McLean

For electron microscope techniques such as ferritin-labeled antibody staining it would be advantageous to have available a simple means of thin sectioning biological material without subjecting it to lipid solvents, impregnation with plastic monomers and their subsequent polymerization. With this aim in view we have re-examined the use of protein as an embedding medium. Gelatin which has been used in the past is not very satisfactory both because of its fibrous nature and the high temperature necessary to keep its solutions fluid. We have found that globular proteins such as the serum and egg albumins can be cross-linked so as to yield blocks which are suitable for ultrathin sectioning.


Author(s):  
Michio Ashida ◽  
Yasukiyo Ueda

An anodic oxide film is formed on aluminum in an acidic elecrolyte during anodizing. The structure of the oxide film was observed directly by carbon replica method(l) and ultra-thin sectioning method(2). The oxide film consists of barrier layer and porous layer constructed with fine hexagonal cellular structure. The diameter of micro pores and the thickness of barrier layer depend on the applying voltage and electrolyte. Because the dimension of the pore corresponds to that of colloidal particles, many metals deposit in the pores. When the oxide film is treated as anode in emulsion of polyelectrolyte, the emulsion particles migrate onto the film and deposit on it. We investigated the behavior of the emulsion particles during electrodeposition.Aluminum foils (99.3%) were anodized in either 0.25M oxalic acid solution at 30°C or 3M sulfuric acid solution at 20°C. After washing with distilled water, the oxide films used as anode were coated with emulsion particles by applying voltage of 200V and then they were cured at 190°C for 30 minutes.


2020 ◽  
Vol 12 (3) ◽  
Author(s):  
Alaa Suhiel Ibrahim

Abstract. This investigation was conducted during 2014, 2015 and 2016 in the field of the citrus experimental station in Ciano, the general corps of scientific agricultural researches. The growth and yield of orange trees (Washington navel 141) budded on seven citrus rootstocks (Sour orange, Troyer citrange, Carrizo citrange, Citrumelo 4475, Citrumelo 1452, Macrophylla and Cleopatra mandarin) and farmed since 1989 have been studied. The results for the average of yield showed that the trees grafted on Cleopatra mandarin (58.33 kg. tree-1) were significantly superior to those grafted on Macrophylla (34.17 kg. tree-1). Orange trees grafted on Citrumelo 4475 and Citrumelo 1452 were significantly superior to other treatments in trunk section area of the rootstock (922.41 and 841.02 cm2, respectively). The greatest fruit fresh weight was in trees grafted on Citrumelo 4475 (284.85 g. fruit-1) which were significantly superior to those grafted on Carrizo and Troyer citrange (232.49 and 236.06 g. fruit-1, respectively). The biggest total soluble solids (%) was in trees grafted on Carrizo and Troyer citrange (12.83% for both treatments) which were significantly superior to those grafted on Sour orangе and Macrophylla (11.5% for both treatments), while the greatest total acids (%) was by Sour orange (2.08%) without significant differences.


Nanomaterials ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1068
Author(s):  
Xinyue Zhang ◽  
Yani Guo ◽  
Wenjun Li ◽  
Jinyuan Zhang ◽  
Hailiang Wu ◽  
...  

The treatment of wastewater containing heavy metals and the utilization of wool waste are very important for the sustainable development of textile mills. In this study, the wool keratin modified magnetite (Fe3O4) powders were fabricated by using wool waste via a co-precipitation technique for removal of Cu2+ ions from aqueous solutions. The morphology, chemical compositions, crystal structure, microstructure, magnetism properties, organic content, and specific surface area of as-fabricated powders were systematically characterized by various techniques including field emission scanning electron microscopy (FESEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), vibrating sample magnetometer (VSM), thermogravimetric (TG) analysis, and Brunauer–Emmett–Teller (BET) surface area analyzer. The effects of experimental parameters such as the volume of wool keratin hydrolysate, the dosage of powder, the initial Cu2+ ion concentration, and the pH value of solution on the adsorption capacity of Cu2+ ions by the powders were examined. The experimental results indicated that the Cu2+ ion adsorption performance of the wool keratin modified Fe3O4 powders exhibited much better than that of the chitosan modified ones with a maximum Cu2+ adsorption capacity of 27.4 mg/g under favorable conditions (0.05 g powders; 50 mL of 40 mg/L CuSO4; pH 5; temperature 293 K). The high adsorption capacity towards Cu2+ ions on the wool keratin modified Fe3O4 powders was primarily because of the strong surface complexation of –COOH and –NH2 functional groups of wool keratins with Cu2+ ions. The Cu2+ ion adsorption process on the wool keratin modified Fe3O4 powders followed the Temkin adsorption isotherm model and the intraparticle diffusion and pseudo-second-order adsorption kinetic models. After Cu2+ ion removal, the wool keratin modified Fe3O4 powders were easily separated using a magnet from aqueous solution and efficiently regenerated using 0.5 M ethylene diamine tetraacetic acid (EDTA)-H2SO4 eluting. The wool keratin modified Fe3O4 powders possessed good regenerative performance after five cycles. This study provided a feasible way to utilize waste wool textiles for preparing magnetic biomass-based adsorbents for the removal of heavy metal ions from aqueous solutions.


1983 ◽  
Vol 61 (3) ◽  
pp. 917-943 ◽  
Author(s):  
Silvano Scannerini ◽  
Paola Bonfante-Fasolo

Electron microscopy is a powerful tool in understanding functional mechanisms in symbiosis (i.e., recognition and transfer of nutrients between partners), but mycorrhizal associations are not yet so well known as host–pathogen and host – mutualistic bacterial associations. However, the study of mycorrhizal ultrastructure has provided some interesting information. In fact unknown symbionts can be recognized with electron microscopy and mycorrhizae can be classified according to a sequence linking intercellular and intracellular interactions between host and fungus. General conclusions can be drawn from this ultrastructural sequence. (i) The most significant cytological feature in mycorrhizae is the presence of an interface through which partners communicate along a vast surface area. This is the key area for symbiotic interactions (both recognition and nutrient transfer) and can vary a great deal mostly in intracellular interactions. (ii) The ultracytochemical aspects of those interfaces, mostly as regards the components of the interfacial matrix, appear quite different from those of host–pathogen associations and suggest a compatibility mechanism. (iii) As regards the transfer of nutrients, even though it has been claimed that transfer of nutrient in all intracellular interactions is achieved by a digestion mechanism of the fungus by the host, available ultrastructural data are not consistent with this hypothesis.


1956 ◽  
Vol 2 (4) ◽  
pp. 445-448 ◽  
Author(s):  
Marie H. Greider ◽  
Wencel J. Kostir ◽  
Walter J. Frajola

An electron microscope study of the nuclear membrane of Amoeba proteus by thin sectioning techniques has revealed an ultrastructure in the outer layer of the membrane that is homologous to the pores and annuli observed in the nuclear membranes of many other cell types studied by these techniques. An inner honeycombed layer apparently unique to Amoeba proteus is also described.


1991 ◽  
Vol 70 (4) ◽  
pp. 1544-1549 ◽  
Author(s):  
D. Negrini ◽  
S. Mukenge ◽  
M. Del Fabbro ◽  
C. Gonano ◽  
G. Miserocchi

In seven anesthetized rabbits we measured the size, shape, and density of lymphatic stomata on the peritoneal and pleural sides of the diaphragm. The diaphragm was fixed in situ and processed for scanning electron microscopy. Results are from 2,902 peritoneal and 3,086 pleural fields (each 1,620 microns 2) randomly chosen from the various specimens. Stomata were seen in 9% of the fields examined, and in 30% of the cases they appeared grouped in clusters with 2-14 stomata/field. Stoma density was 250 +/- 242 and 72 +/- 57 (SD) stomata/mm2 on peritoneal and pleural sides, respectively, and it was similar over the muscular and tendinous portion of the two surfaces. The maximum diameter ranged from less than 1 to approximately 30 microns, with an average value of 1.2 +/- 3.1 micron. The ratio of the maximum to the minimum diameter and the surface area averaged 2 +/- 1.4 and 0.7 +/- 2.4 micron 2, respectively. The maximum and minimum diameter and surface area values followed a lognormal frequency distribution, suggesting that stomata geometry is affected by diaphragmatic tension.


Sign in / Sign up

Export Citation Format

Share Document