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排序方式: 共有381条查询结果,搜索用时 15 毫秒
51.
Shalini Gaur Rudra Sunita Singh Harish H. Haritha Bollinedi Kamalesh Narain Singh Lata Nain Surender Singh Om Prakash Awasthi 《International Journal of Food Science & Technology》2022,57(7):4566-4574
Grewia is a tropical berry rich in anthocyanins and antioxidants but highly perishable in nature. In this study, desirable composite blend of overripe Grewia (Phalsa) berries and cantaloupe was sought for conversion to acetic acid. Composition of raw macerate, and the alcoholic and acetic ferments was analysed for sugars, alcohol and acetic acid. The primary alcohol yield varied significantly (5.75–99.44%) with blend composition. Vinegar from select blend attained 4.98% acidity with 138.57 mg mL−1 of phenols and high anthocyanins retention (74.77%). Gompertz model was used to fit the growth curves of S. cerevisiae and A. aceti (R2> 0.92) during fermentation. Presence of ethyl acetate, iso-pentyl alcohols explained pleasant sweet fruity aroma of resulting vinegar. Thus, high quality functional red fruit vinegar can be obtained to prevent spoilage and utilise the functional potential of this delicate and nutritious berry. 相似文献
52.
Yifei Li Akshay Singh Kate Reidy Seong Soon Jo Frances M. Ross Rafael Jaramillo 《Advanced functional materials》2020,30(36)
The synthesis of large‐area TiS2 thin films is reported at temperatures as low as 500 °C using a scalable two‐step method of metal film deposition followed by sulfurization in an H2S gas furnace. It is demonstrated that the lowest‐achievable sulfurization temperature depends strongly on the oxygen background during sulfurization. This dependence arises because Ti? O bonds present a substantial kinetic and thermodynamic barrier to TiS2 formation. Lowering the sulfurization temperature is important to make smooth films, and to enable integration of TiS2 and related transition metal dichalcogenides—including metastable phases and alloys—into device technology. 相似文献
53.
Kothaplamoottil Sivan Saranya Padinjareveetil Akshay K.K. Padil Vinod V. T. Pilankatta Rajendra George Bini Senan Chandra Černík Miroslav Varma Rajender S. 《Clean Technologies and Environmental Policy》2019,21(8):1549-1561
Clean Technologies and Environmental Policy - An economical and easy one-step method for the biosynthesis of highly stable molybdenum trioxide (MoO3) nanoparticles was developed using gum arabic as... 相似文献
54.
The present paper reports on a recently developed rotary tool micro-ultrasonic drilling (RT-MUSD) process. The RT-MUSD process was utilized for machining of micro-holes in zirconia, silicon and glasswork materials. The effects of work material properties on the performance characteristics (material removal rate (MRR), depth of hole and hole overcut) of RT-MUSD process were investigated by varying the power rating, rotation speed, abrasive size and slurry concentration. Additionally, machined micro-holes and tool surface were analyzed considering microscopic images. The experimental results revealed that the MRR and depth of hole increased by increasing the power rating. An increase in rotation speed up to 300 rpm, abrasive size up to #1200 mesh and concentration up to 20% increased the MRR, depth of hole and decreased hole overcut. The maximum machining rate and hole overcut were observed during machining of silicon followed by glass and zirconia. The fracture toughness and hardness of the work material affected the MRR and tool wear, respectively. Pure brittle fracture mode of material removal was observed in all the work materials during RT-MUSD process. Eventually, the RT-MUSD process was optimized using desirability approach and a micro-hole of depth 4355 µm was achieved using optimal parameter settings. 相似文献
55.
The present research paper is based on a comparative study of stationary tool micro-ultrasonic machining (STMUSM) and rotary tool micro-ultrasonic machining (RTMUSM). Microchannels were developed on glass work material by using both processes. The effect of tool rotation on the performance of micro-USM was investigated. The performance of both processes was compared on the basis of material removal rate (MRR) and depth of channel (DOC) as response characteristics. The power rating, work feed rate, concentration of abrasive slurry, and abrasive mesh size were chosen as variable input process parameters in this investigation. The form accuracy of the fabricated microchannels was analyzed with the help of imaging technique. Also, a qualitative analysis of tool wear was carried out with the help of microscopic images. The experimental results revealed that the tool rotation significantly improved the performance of micro-USM. The RTMUSM resulted in 155% and 147% higher MRR and DOC as compared to STMUSM. The tool wear was also found to be lesser in RTMUSM as compared to STMUSM and as a result of that form accuracy of machined microchannels improved. 相似文献
56.
Accelerating Detailed Tissue-Scale 3D Cardiac Simulations Using Heterogeneous CPU-Xeon Phi Computing
Johannes Langguth Qiang Lan Namit Gaur Xing Cai 《International journal of parallel programming》2017,45(5):1236-1258
We investigate heterogeneous computing, which involves both multicore CPUs and manycore Xeon Phi coprocessors, as a new strategy for computational cardiology. In particular, 3D tissues of the human cardiac ventricle are studied with a physiologically realistic model that has 10,000 calcium release units per cell and 100 ryanodine receptors per release unit, together with tissue-scale simulations of the electrical activity and calcium handling. In order to attain resource-efficient use of heterogeneous computing systems that consist of both CPUs and Xeon Phis, we first direct the coding effort at ensuring good performance on the two types of compute devices individually. Although SIMD code vectorization is the main theme of performance programming, the actual implementation details differ considerably between CPU and Xeon Phi. Moreover, in addition to combined OpenMP+MPI programming, a suitable division of the cells between the CPUs and Xeon Phis is important for resource-efficient usage of an entire heterogeneous system. Numerical experiments show that good resource utilization is indeed achieved and that such a heterogeneous simulator paves the way for ultimately understanding the mechanisms of arrhythmia. The uncovered good programming practices can be used by computational scientists who want to adopt similar heterogeneous hardware platforms for a wide variety of applications. 相似文献
57.
The catalytic oxidation of volatile organic compounds (VOCs) into mainly CO2 and H2O appears promising in the context of the abatement of atmospheric gaseous pollutants and is the subject of this paper. The catalytic oxidation of toluene and m-xylene was carried out in a tubular reactor on a phenolic resin based activated carbon fiber (ACF) impregnated with nitrates of Co, Cr, Ni, and Cu at the reaction temperatures below 300 °C. The extent of the removal (i.e. conversion) of toluene and m-xylene was examined through the breakthrough curves and was found to strongly depend on the types and loading of the metal precursors. The experimental results showed that the reaction rate was significantly affected by O2 concentration below 3% (v/v). The performance of the ACFs impregnated with 5% (w/w) of Ni oxide was found to be superior to that of other metal oxides at reaction temperature between 170 and 290 °C. A surface kinetic mechanism for the catalytic oxidation of volatile organic compound was proposed and incorporated in a transport model developed to explain the experimental breakthrough data. 相似文献
58.
Conductivity of molten Mg(NO3)2. 6H2O + NH4NO3 system containing up to 80 mole percent of the latter was measured in the temperature range 320–400 K. Temperature dependence of conductivity exhibited Arrhenian behaviour. Conductivity—composition isotherms were non-linear indicating weak ordering tendencies. Equivalent conductivity data did not obey Markov equation; deviations have been interpreted in terms of the Tobolsky parameter (θ). Constancy of θ indicate that the water of hydration in the system remains with Mg2+ ions and is unaffected by the addition of NH+4 ions. 相似文献
59.
We have investigated carbon fiber/resin debonding mechanisms using wetting force scanning to examine the fracture surfaces. The wettability of the site of a resin microdroplet (50-150 μm long) on a fiber after debonding is compared with that of the original fiber surface by scanning along the fiber with an appropriate probe liquid. For an HMS/Epon828 system, debonding seems to involve removal of a layer of carbon fiber, while for an AS4/Epon828 system, there is evidence for adhesive failure as well as cohesive failures in both fiber and resin. These contrasting failure mechanisms are consistent with the morphological structures of the carbon fibers studied. 相似文献
60.
In recent research, link stability is getting tremendous attention in mobile adhoc networks (MANETs), because of several impediments that occur in a reliable and robust network. Link stability metric is used to improve network performance in terms of end-to-end delay, data success delivery ratio (DSDR) and available route time (ART). Energy consumption, bandwidth and communication delay of major concern in ad hoc networks. A high mobility of MANET nodes reduces the reliability of network communication. In a dynamic networks, high mobility of the nodes makes it very difficult to predict the dynamic routing topology and hence cause route/link failures. Multicast in MANETs is an emerging trend that effectively improves the performance while lowering the energy consumption and bandwidth usage. Multicast routing protocol transmits a packet to multicast a group at a given time instant to achieve a better utilization of resources. In this paper, node mobility is considered to map better their movement in the network. So, the links with long active duration time can be identified as a stable link for route construction. Variation in signal strength is used to identify whether the direction of the node is towards or away from estimating node. We consider signal strength as QoS metric to calculate link stability for route construction. Efforts are made to identify the link with highly probable longer lifetime as the best suitable link between two consecutive nodes. We predict the movement time of nodes that define the route path to the node destination. Exata/cyber simulator is used for network simulation. The simulation results of the proposed routing protocol are compared with on-demand multicast routing protocol and E-ODMRP, which works on minimum hop count path. Analysis of our simulation results has shown improvement of various routing performance metrics such as DSDR, ART, routing overhead and packet drop ratio. 相似文献