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761.
Different preparation routes for Ti O_2-supported natural and synthetic clinoptilolite(Ti O_2/CP) composites were thoroughly investigated on the basis of sol–gel, hydrothermal, and in-situ hydrothermal methods.The micro-structural features and physicochemical properties of resultant Ti O_2/CPs were characterized via X-ray diffraction patterns, scanning(transmission) electron microscope images, Fourier transform infrared spectra, inductively coupled plasma-optical emission spectrometry methods, BET-isotherms,UV–visible spectra, and surface charge potential distributions. The results showed that in-situ hydrothermal method led to well dispersions of loaded-Ti O_2 particles on the surface of leaf-like CP, while obviously aggregated Ti O_2 on a relatively distorted structure of CP was obtained using sol–gel and hydrothermal methods. Their adsorptive and photocatalytic efficiencies for removal of crystal violet(CV) dye in aqueous solution were also explored under UV-irradiations. The results demonstrated that Ti O_2/CPs synthesized via sol–gel and in-situ hydrothermal methods presented the excellent performances with 98%removal efficiencies as compare to the bare commercial Ti O_2 which achieved 53% removal of CV dye.While, the in-situ hydrothermally synthesized Ti O_2/CPs were the best due to their moderate energy cost,highest adsorption capacities and removal efficiencies. Particularly, the synthetic CPs as supports exhibited synergetic photocatalytic activities for the degradation of CV dye, which is attributed to their high surface areas, better adsorption capability, and fine dispersion of Ti O_2 particles. Adsorption and degradation kinetics of CV dye were found to follow the pseudo-second and pseudo-first order models,respectively. 相似文献
762.
Assessing of energy policies based on Turkish agriculture:: current status and some implications 总被引:1,自引:0,他引:1
In this study, the current energy status of Turkey and the effects of national energy policies on Turkish agricultural support policies are discussed for both current and future requirements. Turkey is an energy-importing country producing 30 mtoe (million tons of oil equivalent) energy but consuming 80 mtoe. The energy import ratio of Turkey is 65–70% and the majority of this import is based on petroleum and natural gas. Furthermore, while world energy demand increases by 1.8% annually, Turkey’s energy demand increases by about 8%. Although energy consumption in agriculture is much lower than the other sectors in Turkey, energy use as both input and output of agricultural sector is a very important issue due to its large agricultural potential and rural area. Total agricultural land area is 27.8 million hectares and about 66.5% of this area is devoted for cereal production. On the other hand, Turkey has over 4 million agricultural farm holdings of which 70–75% is engaged in cereal production. Machinery expenses, mainly diesel, constitute 30–50% of total variable expenses in cereal production costs. It is observed that energy policies pursued in agriculture have been directly affected by diesel prices in Turkey. Therefore, support policy tools for using diesel and electricity in agriculture are being pursued by the Turkish government. 相似文献
763.
Ullah SAIF Zailin GUAN Baoxi WANG Jahanzeb MIRZA Shiyang HUANG 《Frontiers of Mechanical Engineering》2014,9(2):95-105
Assembly lines are useful for mass production of standard as well as customized products. Line balancing is an important issue, in this regard an optimal or near optimal balance can provide a fruitful savings in the initial cost and also in the running cost of such production systems. A survey of different problems in different types of assembly lines and some of the critical and on going research areas are highlighted here. The provided research information is momentous for the research community in assembly line area to proceed further in the presented issues of assembly lines. 相似文献
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765.
Farm to Consumer: Factors Affecting the Organoleptic Characteristics of Coffee. II: Postharvest Processing Factors
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Ahsan Hameed Syed Ammar Hussain Muhammad Umair Ijaz Samee Ullah Imran Pasha Hafiz Ansar Rasul Suleria 《Comprehensive Reviews in Food Science and Food Safety》2018,17(5):1184-1237
The production and consumption of coffee are increasing despite the roadblocks to its agriculture and global trade. The unique, refreshing, and stimulating final cupping quality of coffee is the only reason for this rising production and consumption. Coffee quality is a multifaceted trait and is inevitably influenced by the way it is successively processed after harvesting. Reportedly, 60% of the quality attributes of coffee are governed by postharvest processing. The current review elaborates and establishes for the first time the relationship between different methods of postharvest processing of coffee and its varying organoleptic and sensory quality attributes. In view of the proven significance of each processing step, this review has been subdivided into three sections, secondary processing, primary processing, and postprocessing variables. Secondary processing addresses the immediate processing steps on the farm after harvest and storage before roasting. The primary processing section adheres specifically to roasting, grinding and brewing/extraction, topics which have been technically addressed more than any others in the literature and by industry. The postprocessing attribute section deals generally with interaction of the consumer with products of different visual appearance. Finally, there are still some bottlenecks which need to be addressed, not only to completely understand the relationship of varying postharvest processing methods with varying in‐cup quality attributes, but also to devise the next generation of coffee processing technologies. 相似文献
766.
Muhammad Attique Khan Tallha Akram Muhammad Sharif Tanzila Saba Kashif Javed Ikram Ullah Lali Urcun John Tanik Amjad Rehman 《Microscopy research and technique》2019,82(6):741-763
Skin cancer is being a most deadly type of cancers which have grown extensively worldwide from the last decade. For an accurate detection and classification of melanoma, several measures should be considered which include, contrast stretching, irregularity measurement, selection of most optimal features, and so forth. A poor contrast of lesion affects the segmentation accuracy and also increases classification error. To overcome this problem, an efficient model for accurate border detection and classification is presented. The proposed model improves the segmentation accuracy in its preprocessing phase, utilizing contrast enhancement of lesion area compared to the background. The enhanced 2D blue channel is selected for the construction of saliency map, at the end of which threshold function produces the binary image. In addition, particle swarm optimization (PSO) based segmentation is also utilized for accurate border detection and refinement. Few selected features including shape, texture, local, and global are also extracted which are later selected based on genetic algorithm with an advantage of identifying the fittest chromosome. Finally, optimized features are later fed into the support vector machine (SVM) for classification. Comprehensive experiments have been carried out on three datasets named as PH2, ISBI2016, and ISIC (i.e., ISIC MSK‐1, ISIC MSK‐2, and ISIC UDA). The improved accuracy of 97.9, 99.1, 98.4, and 93.8%, respectively obtained for each dataset. The SVM outperforms on the selected dataset in terms of sensitivity, precision rate, accuracy, and FNR. Furthermore, the selection method outperforms and successfully removed the redundant features. 相似文献
767.
The major aroma components in grapes and wine include free volatile compounds and glycosidic nonvolatile compounds. The latter group of compounds is more than 10 times abundant of the former, and constitutes a big aroma reserve in grapes and wine. This review summarizes the research results obtained recently for the identification of aroma glycosides in grapes and wine, including grape glycoside structures, differences in aroma glycosides among grape varieties, hydrolysis mechanisms, and the factors that influence them. It also presents the analytical techniques used to identify the glycosidic aroma precursors. The operational strategies, challenges, and improvements of each step encountered in the analysis of glycosidic aroma precursors are described. This review intends to provide a convenient reference for researchers interested in the methods used for the determination of the aroma glucosides composition and the recognition of their chemical structures. 相似文献
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770.
Rahim Ullah Gowhar Ali Ajmal Khan Sajjad Ahmad Ahmed Al-Harrasi 《International journal of molecular sciences》2021,22(17)
Alzheimer’s disease (AD) is a chronic neurodegenerative disorder. This study was designed to investigate the effects of cyclopentanone derivative i.e., 2-(hydroxyl-(3-nitrophenyl)methyl)cyclopentanone (3NCP) on behavior, amyloid β (Aβ) plaque deposition, and βAPP cleaving enzyme-1 (BACE-1) expression in the 5xFAD mouse brain. In this study, computational studies were conducted to predict the binding mode of the 3NCP with target sites of the β-secretase. In vivo studies were performed on the 5xFAD mice model of AD using different behavioral test models like light/dark box, elevated plus maze (EPM), and the Barnes maze tests for the assessment of anxiety, spatial learning and memory. The thioflavin-S staining, immunohistochemistry (IHC), and RT-PCR studies were carried out to find the effect of the 3NCP on the β-amyloid plaques formation and BACE-1 expression. The results of the computational studies showed that the 3NCP has excellent binding affinities for beta-secretase. The light/dark box study depicted that the 3NCP does not cause anxiety. The 3NCP treatment effects in the EPM and Barnes maze tests showed a significant effect on learning and memory. Furthermore, the results of the thioflavin staining and IHC revealed that the 3NCP significantly reduced the formation of the beta-amyloid plaques in brain tissues. Moreover, the RT-PCR study showed that 3NCP significantly reduced the BACE-1 expression in the brain. Conclusively, the results of the current study demonstrate that the 3NCP may be a potential candidate for AD treatment in the future. 相似文献