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101.
A dense nanostructured 1.5Ti-Al2O3 composite (volume fraction of Al2O3; 0.62) was simultaneously synthesized and consolidated in a high-frequency induction heated combustion synthesis method within 2 min in one step from mechanically activated powders of 1.5 TiO2 and 2 Al. Simultaneous combustion synthesis and consolidation were accomplished under the combined effects of an induced current and mechanical pressure. Highly dense 1.5Ti-Al2O3 with a relative density of up to 99.8 % was produced under simultaneous application of 60 MPa of pressure and an induced current. The average hardness and fracture toughness values of the composite were 1513 kg/mm2 and 7 MPa·m1/2, respectively.  相似文献   
102.
Mushrooms have been previously investigated for their immune‐modulating and anti‐inflammatory properties. We examined whether the anti‐inflammatory properties of Sarcodon aspratus ethanol extract (SAE) could elicit protective effects against dextran sulfate sodium (DSS)‐induced colitis in vivo. Male C57/BL6 mice were randomly assigned to 1 of 4 treatment groups: control (CON; n = 8), DSS‐treated (DSS; n = 9), DSS+SAE at 50 mg/kg BW (SAE50; n = 8), and DSS+SAE at 200 mg/kg BW groups (SAE200; n = 9). DSS treatment induced significant weight loss, which was significantly recovered by SAE200. Although SAE did not affect DSS‐mediated reductions in colon length, it improved diarrhea and rectal bleeding induced by DSS. SAE at 200 mg/kg BW significantly attenuated IL‐6 and enhanced IL‐10 expression in mesenteric lymph nodes (MLN), and significantly reduced IL‐6 levels in splenocytes. SAE200 also significantly attenuated DSS‐induced increase in IL‐6 and IL‐1β, and reductions in IL‐10 in colon tissue. High levels of SAE were also observed to significantly decrease inflammatory COX‐2 expression that was upregulated by DSS in mice colon. These findings may have relevance for novel therapeutic strategies to mitigate inflammatory bowel disease‐relevant inflammatory responses, via the direct and indirect anti‐inflammatory activity of SAE. We also found that SAE harbors significant quantities of total fiber and β‐glucan, suggesting a possible role for these components in protection against DSS‐mediated colitis.  相似文献   
103.
回顾了2016年底在悉尼召开的国际正渗透研讨会的主要内容,概括了近年来正渗透技术研究和应用的最新进展。在膜材料方面,提高水通量应着重于降低支撑层结构参数,而不是提高分离层的渗透性能。提高分离层的截留率和耐污染性是提高膜性能的关键。对于各种类型的驱动溶质而言,无机盐很可能是最为现实可靠的驱动溶质。正渗透技术在渗透稀释和与其他分离技术的耦合过程处理高含盐污染水源中有潜在应用,然而渗透能发电在短期很难成为主流的新兴能源。  相似文献   
104.
Nanopowders of Ni and Al2O3 were synthesized from 3NiO and 2Al powders by high energy ball milling. Nanocrystalline Al2O3 reinforced composite was consolidated by high frequency induction heated sintering method within 2 min from mechanically synthesized powders of Al2O3 and 3Ni. The relative density of the composite was 96%. The average hardness and fracture toughness values obtained were 645 kg/mm2 and 6.3 MPa m1/2, respectively.  相似文献   
105.
Dense nanostructured 4ZrSi2-Si3N4 composite was synthesized by high frequency induction heated combustion synthesis (HFIHCS) method within 1 min in one-step from mechanically activated powders of 4ZrN and 11Si. Simultaneous combustion synthesis and consolidation were accomplished under the combined effects of an induced current and mechanical pressure. Highly dense 4ZrSi2-Si3N4 with relative density of up to 98% was produced under simultaneous application of a 60 MPa pressure and the induced current. The average grain size and mechanical properties of the composite were investigated.  相似文献   
106.
Peer-to-Peer Networking and Applications - The application of IT in all industrial facilities has led to the use of special-purpose systems in diverse areas. As such, special-purpose systems have...  相似文献   
107.
Currently, most records are produced and stored digitally using various types of media storage and computer systems. Unlike physical records such as paper-based records, identifying, collecting, and analyzing digital records require technical knowledge and tools that are not found in archival institutions. As a result, archival institutions face challenges in their attempt to collect digital archives. One approach to overcome this problem is for archival institutions to use digital forensic knowledge and technologies. In this paper, we propose the Digital Archive Management System that integrates digital forensic technologies and archival information management systems to acquire, identify, analyze, and manage digital records in archival intuitions.  相似文献   
108.
A molecular dynamics simulation study of friction in boundary lubrication was conducted in order to investigate the atomic-scale behavior of lubricant molecules during sliding motion. The simulated system consisted of two silicon (001) semi-infinite substrates lubricated by a three-layer film of dodecane. Silicon was modeled using the Stillinger–Weber potential, and the dodecane with the Consistent Force Field function; a novel scheme was used to generate the silicon–dodecane interaction potentials. The simulations show that dodecane molecules strongly prefer to adsorb into the ledges on the silicon surface. The orientation of the adsorbed molecules depends, however, on the concentration of the lubricant at the surface, showing a tendency to stand up at high lubricant concentrations. In sliding, the dodecane layers adsorbed on the surfaces behave as a solid, whereas the middle layer exhibits liquid-like characteristics. The friction coefficient of this well-lubricated case was calculated to be 0.08.  相似文献   
109.
The presence of zearalenone (ZEN) in Korean foods such as barley, barley-based foods, corn, corn-based foods, fruits and vegetables was investigated by direct competitive enzyme-linked immunosorbent assay (dcELISA) and the liquid chromatography (LC) method. A total of 164 samples was collected from Seoul, Korea, in 1998 and 1999 including 30 barley, 32 barley-based foods, 18 corn, 47 corn-based foods, 19 dried red pepper, nine dried jujube, and nine dried persimmon. Average recoveries of ZEN from barley and corn by dcELISA were 138 and 145%, and by LC were 91 and 83% respectively at spiking levels of 5- 500ngg -1 . The detection limit for ZEN was 3ngg -1 by dcELISA and 4ngg -1 by LC. From 164 samples analysed, ZEN was found by dcELISA in 35 samples (21%) with a mean level of 30ngg -1 . Barley-based foods had the highest incidence of ZEN (38%) followed by barley (33%), corn-based foods (26%) and corn (22%). No ZEN was detected in any red pepper, jujube or persimmon samples. A high degree of correlation (r 2 = 0.86) was observed between the 35 positive samples detected by dcELISA and 31 samples by LC.  相似文献   
110.
In the proposed scheme, micro Unmanned Aerial Vehicle (micro UAV) is used to find the target and the UAV group is controlled to constantly provide location information to the base while the target is moving. UAVs have a limited communication range and information transmission is only possible through communication among the UAVs. After locating the target within the search area, the UAVs move toward the base station in order to transmit the information to the base station using multihop connectivity. In the proposed scheme, when communication is not possible among the UAVs because the target moves too far away from the base station, UAVs retain the information of the target and move toward the base station, deliver the information to another UAV, return to the target, and repeat the process. The base station calculates the range of target’s location upon receiving the information, and determines whether target tracking is possible with the current number of UAVs. The performance of the proposed scheme was evaluated by a simulation using NS-2.  相似文献   
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