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Neural Computing and Applications - Lung cancer is a deadly disease if not diagnosed in its early stages. However, early detection of lung cancer is a challenging task due to the shape and size of...  相似文献   
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To study the ion exchange kinetics of heavy metal ions on the organic–inorganic composite cation exchanger poly-o-toluidine Zr(IV) tungstate, Nernst–Planck was computer simulated. Simulated numerical results for counter ions (Cu, Zn, Cd and Pb) of equal valence and four different ionic mobilities are presented to understand the ionic diffusion process. These results are based on the fractional attainment of equilibrium U(τ), of the counter ions under study. The forward (M2+–H+) and reverse (H+–M2+) ion exchange processes are justified as the particle diffusion phenomenon. The self-diffusion coefficient (D o ), energy of activation (E a ), and entropy of activation (?S*) have also been estimated to understand the ion exchange process occurring over the surface of this cation exchanger and indicated that the ion exchange process is feasible and spontaneous. It is concluded that the difference in activation energies and entropy of activation may facilitate the separation of metal ions. The regeneration capability of this cation exchanger was also explained.  相似文献   
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目的 提高D16T铝合金的耐磨损性能。方法 通过向硅酸盐和磷酸盐混合电解液体系中添加2 g/L纳米TiO2添加剂,利用微弧氧化技术在其表面制备微弧氧化陶瓷膜。采用X射线衍射仪(XRD)、扫描电镜(SEM)、能谱分析仪(EDS)、显微硬度计、厚度测试仪、摩擦磨损试验机等,研究了纳米TiO2添加剂对D16T铝合金微弧氧化膜的结构和耐磨损性能的影响及机理。结果 纳米TiO2的添加使得微弧氧化膜层的表面变得更加平整、致密,具有更少的微孔和裂纹,大大改善了膜层结构。相比于未添加纳米TiO2的电解液中制得的微弧氧化膜,在含纳米TiO2的电解液中所制得的微弧氧化膜中有新相TiO2生成,并且促使更多的α-Al2O3相和γ-Al2O3相生成,使膜层厚度得到明显增加,膜厚达31.2 μm,显微硬度也得到显著提高,达510HV。纳米TiO2的添加,降低了D16T微弧氧化膜层试样的摩擦系数,平均摩擦系数为0.45,明显低于不含纳米TiO2的D16T微弧氧化膜层试样的摩擦系数(0.75)。结论 加入到电解液中的纳米TiO2在微弧氧化反应过程中已进入到所形成的氧化膜层,并且填充了膜层中的微孔和裂纹,改善了膜层结构,增加了膜层厚度,显著提高了微弧氧化膜层的显微硬度和耐磨损性能。  相似文献   
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Surghar mountain belt has comparatively less natural resources of floral diversity because it is composed of minerals of different kinds making it less favorable for the growth of different vegetation. The pollen morphology of some selected plants from Surghar belt Mainwali has been evaluated. The pollen grains were measured and demonstrated using scanning electron microscopy (SEM). The examined plant specimens have a difference in size, shape, polarity, and their exine ornamentation. The pollen taxa show a huge variation in size and sculpture. Pollen fertility has also been estimated, shows that the selected plants are well‐known in the Surghar belt. The need of the hour is to conserve these plants having a higher fertility rate to cope with the deforestation in an area. The conclusion does not favor theories in which deforestation results in fast growth in population. It shows that the irrational management and unlawful cutting down of woods neglected by the forest department are the main causes of deforestation in the mountain belt of Mianwali. The findings show the importance of morphological characteristics in the identification of natural resource species in the area.  相似文献   
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Journal of Applied Electrochemistry - Large area MoS2 ultra-thin film deposition is one of the big challenges in the recent years. Electrodeposition provides an opportunity to grow such ultra-thin...  相似文献   
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This research was aimed at processing of metallic fiber hybrid spun yarns consisting of polyester/stainless steel and viscose/stainless steel staple fibers to achieve better electrical conductivity. Conventional ring spinning machine and ring twister machine were used to produce the single and plied yarns respectively. The linear electrical resistance of yarns was analyzed with reference to the three levels of twist multiplier (TM) for same yarn count, three levels of yarn fineness (Ne) at the same TM level, and number of plies for the same final yarn count. These results showed that by increasing twist, the electrical conductivity of yarn was increased. However, yarn fineness was in inverse relation with the electrical conductivity of yarns. The effect of yarn plying and twisting to produce the Ne 10s yarn was also found critical in governing the electrical properties. The electrical conductivity of viscose and stainless steel hybrid yarn was found more sensitive to increase with an increase in relative humidity contrary to that of polyester and stainless steel hybrid yarns. The findings of the study are significant to produce the hybrid spun conductive yarns for their potential applications in a variety of tailor-made functional, protective and smart textiles.  相似文献   
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Wireless Personal Communications - The number of aged and disabled people has been increasing worldwide. To look after these people is a big challenge in this era. However, scientists overcome the...  相似文献   
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Piezoelectric energy harvesting from mechanical vibrations is a reliable technology to charge low power electronic equipment. It has been reported in the literature that low frequency broadband vibrations cannot be harvested effectively using linear piezoelectric energy harvester (PEH). In this paper a bistable nonlinear PEH with two distinct energy wells generated using repulsive magnetic interactions between a cantilever magnetic proof mass and an external magnet is considered. It has been modeled using finite element method and validated with experimental results. Experimental results verify that, for our study, distance between magnetic proof mass and external magnet of 1.32 T flux density should be less than or equal to 8.5?mm for maintaining bistability. This distance also affects to the resonance frequency of harvester. Maximum efficiency of the harvester has been noticed at 8.5mm. Further it has been shown experimentally that the bistable nonlinear piezoelectric energy harvester takes almost half of the time taken by its linear counterpart to charge a 20 mAh battery.  相似文献   
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The large-scale multiple input multiple output (LS-MIMO) systems are equipped with a large number of antennas at the base station. These systems are capable of serving a larger number of user terminals, with massive gains in the form of energy and bandwidth efficiency. The energy efficiency of LS-MIMO system depends on the overall power consumption and data rate. In this paper, we have improved the energy efficiency of the LS-MIMO system by using maximum ratio transmission/combining and zero forced linear pre-coding schemes in single and multi-cell scenarios. We have jointly considered the uplink and downlink communications to propose an improved, more practical and more realistic power consumption model. The proposed model deliberates the power required for the power amplifier, linear processing and the circuit components at the base stations and user terminals. The outcome of this work provides a significant improvement in terms of energy efficiency and area throughput. The analytical results illustrate that the LS-MIMO systems achieve the maximum energy efficiency and area throughput wherein larger number of transmit antennas are installed at the base station to serve comparatively greater number of users terminals. The mathematical results depict the similar performance for imperfect channel state information in multi-cell setups. All aspects of power consumption during bidirectional communication are considered to provide precise results. Hence, the improvements in simulations results support the accuracy of the proposed model.  相似文献   
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