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991.
Community detection can effectively mine the characteristics of the network as well as the hidden information.Local expansion is a commonly used method of community detection,and it can be divided into two steps:the selection of seeds and the local expansion.Therefore,in order to analyze the advantages and disadvantages of the existing methods and their application,these methods about the selection of seeds,local expansion and evaluation were summarized,compared and analyzed.Then,the application and the research difficulties of community detection based on local extension were summarized.Finally,the research directions of community detection based on local expansion were given. 相似文献
992.
The insecticidal efficacy of ozone was evaluated against the adults of Callosobruchus maculatus (F.) and C. chinensis L. on stored cowpea seeds under laboratory conditions. Ozone was assessed at concentrations of 0.25, 0.5, 1.0, 1.5, and 2.0 g/m3. The effect of ozone treatments on the adult mortality after 1, 3, 5 and 7 days of treatment, progeny production after 45 days, cowpea seed weight loss, seed germination and chemical constituents of cowpea seeds were determined. Adult mortality of C. maculatus and C. chinensis was improved with the increase in ozone concentration. Thus, all tested concentrations caused complete adult mortality of C. chinensis after 7 days of treatment, while the concentrations of 1.0, 1.5, and 2.0 g/m3 caused complete adult mortality of C. maculatus after the same periods. Progeny of both species was significantly decreased in all ozone concentrations after 45 days of treatment. Nevertheless, strong suppression in progeny production was achieved at the highest concentration of ozone (2.0 g/m3). Also, the ozone treatment at the highest concentration protected the cowpea seeds from damage caused by C. maculatus and C. chinensis for 45 days. In addition, there was no significant effect of ozone treatments on the cowpea seed germination compared with untreated seeds. Moreover, the chemical analysis of treated cowpea seeds showed a slight decrease in protein, fat, carbohydrate, moisture, total phenolics, total flavonoids and tannins contents, and a slight increase in fiber and ash contents compared with untreated cowpea seeds. Our findings suggest the ozone can be effectively used for the control C. maculatus and C. chinensis and can provide sufficient protection of stored cowpea seeds. 相似文献
993.
Aqsa Aziz Mushtaq Ahmad Riaz Ullah Ahmed Bari Muhammad Yahya Khan Muhammad Zafar Shazia Sultana Rozina Maria Ameen Maryam Anar 《Microscopy research and technique》2022,85(3):900-916
Investigation of alternative energy sources is need of current time due to growing power crisis and associated environmental issues. Biodiesel is considered as sustainable power source and promising alternative to fossil fuels. Therefore, our current investigation aimed to identify micromorphological characters of 10 novel nonedible oil-yielding seeds through scanning electron microscopy. It was revealed from light microscopic study that there is variation in seed size from 3 to 15 mm in length and 2 to 11 mm in width. Likewise, a huge variation in color was observed such as light green, greenish yellow, blackish brown, and various shades of brown. Presence and absence of Hilum was observed, and compression of seeds varied from depressed, lateral, and dorsoventral. Seed's shape differs from ovate, clavate, triangular ovate, cuneiform, ovoid, and elliptical shape. Seed oil content fall in range of 18–58% (wt/wt). Free fatty acid content of the seeds varies from 0.3 to 3.1 mg KOH/g. Ultrastructure of seeds exhibited huge variation in shape, size, periclinal wall, anticlinal wall, and surface ornamentation. Nonedible seeds varied in wall structure from angular, wavy, dentate entire, irregular, puzzled, elongated, even, and polygonal. The periclinal wall arrangements show alteration from flat, looped, raised, depressed, lofty, even, pentagonal, polygonal, and undulate seed margins. Outcomes of this investigation recommended that scanning electron microscopy could act as a helpful tool in disclosing the hidden micromorphological characters among nonedible oil-yielding seeds and subsequently helping in correct, authentic seed identification and classification as potential feedstock for biodiesel. 相似文献
994.
无溶剂法合成沸石法在多个方面优于常规水热合成法, 近年来引起广泛关注, 但是采用该方法合成的微孔SAPO-34沸石催化剂的催化寿命较短, 无法满足甲醇制烯烃工业应用的要求。本研究中开发了一种改良的无溶剂法, 使用该法合成了具有优异甲醇制烯烃反应性能的SAPO-34催化剂。该法在合成体系中引入酸活化晶种, 通过调节沸石晶化动力学来调控催化剂的物理化学性质。采用不同技术对无溶剂法合成的系列SAPO-34催化剂的结构性质进行了分析表征。结果表明:与未引入晶种合成的父代样品相比, 添加晶种得到的子代SAPO-34样品具有更高的结晶度、比表面积及低的强酸中心密度, 对甲醇制烯烃反应的催化寿命可延长到480 min, 远远优于对应的父代样品(40 min)。这一结果证实了无溶剂合成中晶种的使用可有效调节沸石的性质, 可见该方法在提高沸石催化性能方面具有巨大潜力。 相似文献
995.
Sumreen Dawood Mushtaq Ahmad Muhammad Zafar Muhammad I. Ali Khalid Ahmad Shazia Sultana Anwer Usma Moona Nazish Maryam A. Butt Fethi A. Ozdemir Omer Kilic 《Microscopy research and technique》2020,83(2):165-175
Exploration of substitute energy feed‐stocks is the much‐debated topic in the scientific society due to increasing power crises and related ecological concerns. As a source of sustainable energy, biodiesel turns out to be the best alternative to petro fuels. In this context, nonedible oil‐producing seeds might be a potential source for biodiesel production owing to their environment‐friendly nature and cost‐effectiveness. The current study, consequently, deals with the investigation and identification of micro‐morphological characters between six novel nonedible oil‐bearing seeds employing scanning electron microscopy as possible biodiesel feed‐stocks. Light microscopic examinations show that seed size varies from 0.3 to 1.3 cm in width and 0.5 to 1.5 cm in. Additionally, a large difference in seed color ranges from dark brown, black, and various shades of light brown was also witnessed. The FFA content of the seeds ranges in 0.3–4.1 mg KOH/g, and the seed oil content fall in 30–65% (w/w) range. SEM‐mediated seed ultrastructure investigations displays greater variation in seed size, shape, color, periclinal wall shape, and sculpturing and so on. All the seeds differ from rounded, ovoid, ovate, oblong, flattened, and elliptical shape. Greater variation in seed wall structure has been seen from angular, entire, irregular, straight, elongated, smooth, and polygonal. The periclinal wall arrangements show alteration from flat, depressed, elevated, smooth, pentagonal, bullate, and coarse seed margins. The results obtained from the current study suggest that scanning electron microscopy could be a beneficial tool in vitalizing the hidden micromorphological characters among various nonedible oil producing seeds, which eventually helps in exploration, correct identification, seed classification, and authentication in future. 相似文献
996.
997.
998.
Francisco J. Rivero Maria Lourdes González-Miret María José Jara-Palacios Ignacio García-Estévez María Teresa Escribano-Bailón Francisco J. Heredia Belén Gordillo 《International Journal of Food Science & Technology》2020,55(1):389-396
Overripe seeds are wine by-products from grapes submitted to postharvest sun drying, which induce phenolic biosynthesis and polymerisation. Overripe seeds from Pedro Ximénez (PX) and Moscatel (MO) sun-dried grapes were compared as copigments sources to modulate grape anthocyanin (GA) colour and stability in simulated wine conditions. RRLC/MS analysis proved that overripe seeds contain specific phenolic mixtures capable of inducing positive quantitative and qualitative colour changes in GAs, evidenced by differential colorimetry. Copigmentation effects significantly varied depending on the overripe seed variety, related to their qualitative phenolic composition and content. MO extracts richer in gallic acid, catechin and procyanidin B1 led to the stronger colour intensification and perceptible qualitative changes. PX extracts richer in epicatechin, procyanidins B2, B2-GAL and B7 behaved as weak copigments. Overripe seed copigments preserved better GAs colour stability during storage leading to the formation of new anthocyanin-derived pigments, being the stabilising effect stronger with those of MO variety. 相似文献
999.