Textural characteristics,surface chemistry and oxidation of activated carbon

Numerous researches were reviewed and interpreted to depict a comprehensive illustration of activated carbon and its behavior towards oxidation.Activated carbon as one of the most important adsorbents is tried to be described in this review paper by terms of its＂Textural Characteristics＂and＂Surface Chemistry＂.These two terms,coupled with each other,are responsible for behavior of activated carbon in adsorption processes and in catalytic applications.Although as-prepared activated carbons are usually nonselective and their surfaces suffer from lack of enough reactive groups,their different aspects may be improved and developed by diverse types of modifications.Oxidation is one of the most conventional modifications used for activated carbons.It may be used as a final modification or as a pre-modification followed by further treatment.In this paper,methods of oxidation of activated carbon and other graphene-layer carbon materials are introduced and wet oxidation as an extensively-used category of oxidation is discussed in more detail.

Sedimentary facies and textural characteristics of Cretaceous sandstones in the southern Bida Basin,Nigeria:Implication for reservoir potential and depositional environment

A study of sedimentary facies,mineral and textural characteristics of sections of conglomerates/pebbles and sandstone facies found within the Lokoja and Patti Formations in southern Bida Basin,Nigeria,is carried out to evaluate the paleo-environment and reservoir quality of the sandstones of the formations through field observations and textural and mineralogical(using X-Ray Diffractogram)analyses.Nine lithofacies are identified and grouped into three main facies associations.These sedimentary facies suggest deposition in both foreshore and estuaries.The mineral analysis(XRD)shows that the quartz content in sandstone facies of the Lokoja Formation ranges between 49%and 67%,and that of the Patti Sandstone between 43%and 56%,indicating a quartz dominance.The granulometric studies reveal that the Lokoja Formation comprises coarse-to medium-grained(-0.63 to 1.30φ)sandstone with moderatepoor sorting of 0.72e1.824.On the other hand,medium to fine-grained sandstones dominate the Patti Formation,which is averagely poorly sorted(1.29-1.54φ).The sandstones are coarsely skewed to finely skewed,with the kurtosis ranging from very platykurtic to leptokurtic.Morphological results of the pebbles from both Lokoja and Patti Formations indicate that the study areas are mainly characterized by the interplay of both wave and fluvial processes,which suggests that the environment of deposition of sandstone facies is predominantly of the fluvial to the shallow marine environment with the indication of tidal influence.Integrating sedimentary facies and textural results suggests subtidal sand ridge/foreshore,estuarine mudflat,and estuarine delta environments with fluvial influences.Evidence from the textural and mineral characteristics indicate that the sandstone facies of the Lokoja and Patti Formations are fairly matured and can act as potential hydrocarbon reservoirs in the formations.The facies,XRD mineral,and textural results have revealed potential hydrocarbon reservoir areas and paleo-depositional features of the Lokoja and Patti Formations.

Textural Characteristics and Depositional Environment of Ngrayong Sandstone (Middle Miocene) from Rembang Area, Northeast Java, Indonesia

Granulometric analysis of Ngrayong sandstone samples from Rembang area of NE Java (Indonesia) has been carried out to examine the textural characteristics and elucidate depositional environment. The result data from the grain size analysis indicates that the Ngrayong sediments are classified as sand or muddy sands. They are very fine- to medium-grained (phi values: 1.67 to 3.35), moderately- to well-sorted (standard deviation: 0.19 to 0.57), strongly fine-skewed to strongly coarse-skewed (skewness values: 4.82 to −5.97), and very platykurtic to very leptokurtic (kurtosis values: 0.36 to 2.41). Sandstone samples show unimodal grain size distribution. The sediments are interpreted to be transported in all three modes-traction, saltation and suspension, however, suspension and rolling are the major processes during transportation. Discriminant functions indicate diversity in the depositional environment for the sandstones. However, shallow marine is regarded as the dominant depositional environment. The preponderance of fine-grained sediments and lack of coarse sands suggest low to moderate energy conditions during deposition of Ngrayong sediments.

Texture Characteristics of Thin Grain Oriented Silicon Steel Sheet Produced by Cross Shear Rolling

Commercial grain oriented silicon steel was cold rolled to thickness from 0.06 to 0.10 mm by cross shear rolling, then annealed in vacuum or a hydrogen atmosphere furnace. Deformation textures of the sheets were researched by ODF method and reverse pole figure quantitative analyses. The results indicate that: in the condition of the cross shear rolling, the deformation texture of rolled sheet is generally similar to that of conventional rolled sheet, however, the texture distribution through the thickness is asymmetrical. With mismatch speed ratio increasing, the amount of Goss texture increases. With reduction ratio increasing, the intensity of γ-fiber becomes strong.

Study on Nutrients and Texture of Pickled Huangzhou Radish

[Objectives]The changes in the nutrient contents and texture of pickled Huangzhou radish with pickling time were studied to further improve its edible value and improve its sensory evaluation.[Methods]Huangzhou radish as a raw material was pickled,and exploration was conducted through the following aspects:with the extension time of pickling time,the changes in nutrient contents such as reducing sugars,free amino acids and ascorbic acid were detected in pickled Huangzhou radish,and the changes in the texture characteristics of pickled Huangzhou radish such as hardness,viscosity,elasticity,recoverable deformation,compression power and chewiness were detected.[Results]As the pickling time became longer,the reducing sugar content in pickled Huangzhou radish gradually increased,and when the pickling time exceeded 13 d,the reducing sugar content showed a downward trend;the ascorbic acid content gradually decreased,and the decreasing rate was relatively lower after the pickling time exceeded 7 d;and the amino acid content first increased and then decreased,and when the pickling time exceeded 13 d,the content exhibited basically no change.The hardness of the radish gradually decreased;the viscosity first decreased and then slowly increased;the recoverable deformation first increased and then decreased;the elasticity first increased and decreased;and the chewiness first increased and then decreased.Through this experiment,it is concluded that the pickled Huangzhou radish has richer nutrients and the best taste when the pickling time is 7-10 d.[Conclusions]This study provides a theoretical reference for producing and processing pickled Huangzhou radish,improving the quality of pickled Huangzhou radish and increasing the nutritional value of the product.

Fast Sub-Pixel Motion Estimation Algorithm For H.264

A novel fast sub-pixel search algorithm is proposed to accelerate sub-pixel search. Based on the features of predicted motion vector (PMV) and texture direction observed, the proposed method effectively filters out impossible points and thus decreases 11 searched points in average during the sub-pixel search stage. A threshold is also adopted to early terminate the sub-pixel search. Simulation results show that the proposed method can achieve up to 4.8 times faster than full sub-pixel motion search scheme (FSPS) with less than 0.025 dB PSNR losses and 2.2% bit-length increases.

Influences of the Texture Characteristic and Interdendritic LPSO Phase Distribution on the Tensile Properties of Mg–Gd–Y–Zn–Zr Sheets Through Hot Rolling

The Mg–Gd–Y–Zn–Zr alloy sheets with different texture characteristics and distribution of the interdendritic long periodstacking ordered(LPSO) phases were fabricated through altering the final rolling reduction(FRR). The results showed that the texture characteristic was closely related to FRR and affected the tensile properties of the resulted sheets to some extent. The Schmid factor(SF) of the basal 〈a〉 slip improved with further FRR, which was ascribed to that the dynamic recrystallization(DRX) grains expand into the deformed grains with basal texture. However, the improvement of the tensile yield strength(TYS) with further FRR indicates that the strengthening effect from DRX grains surpasses the weakening effect from the elevated SF. The formation of the line-distributed interdendritic 14 H-LPSO phases can also affect the tensile properties of the resulted sheets. The line-distributed interdendritic 14 H-LPSO phases along rolling direction(RD) can act as reinforcing fiber and contribute to the higher TYS along RD and 45° to some extent, which resulted in the higher TYS along 45° compared with that along transverse direction(TD) for each resulted sheet under the circumstance of approximate basal 〈a〉 and pyramid 〈c + a〉 friction stress. Thus, the tensile yield strength is not only related to the texture, but also depends on the grain size and line-distributed interdendritic LPSO phases. The micro-cracks spread perpendicular to the tension direction, and thus, the larger cracks form within the line-distributed 14 H-LPSO phases during tension along TD, which accounts for the lower fracture elongation along TD.

Identification of Chinese Materia Medicas in Microscopic Powder Images

This paper describes an identification system for Chinese Materia Medicas （CMMs） in microscopic powder images. The imaging processing of the microscopic powder image is very complex because of the low contrast, blurry boundaries, overlapping objects, and messy background. Therefore, the object detection must segment the significant microscopic structures from the complex image. The objects are detected in these images using an adaptable interactive method. After identifying the significant microscopic structures, the system identifies 14 features belonging to three main characteristics. These features form a 14-dimensional vector that represents the microscopic structures. The multi-dimensional vector is then analyzed using a feature assignment algorithm that picks the most notable features to construct a decision tree with thresholds. The identification system consists of a coarse classifier based on the decision tree and a fine classifier using similarity measurements to rank the possible results. Tests on 528 images from 24 different kinds of microscopic structures show the system effectiveness and applicability.