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91.
92.
Lilan Zhang Yali Guo Anam Iqbal Bo Li Deyan Gong Wei Liu Kanwal Iqbal Weisheng Liu Wenwu Qin 《International Journal of Hydrogen Energy》2018,43(3):1251-1260
In this work, a facile one-step hydrothermal method was developed to fabricate three types different of nanomaterials: the two-dimension (2D) of MoS2 nanosheets; 3D spherical CuS nanoparticles; and 3D flower-like heterostructure of MoS2/CuS nanohybrid, respectively. The as-synthesized MoS2, CuS and MoS2/CuS were characterized by transmission electron microscopy (TEM), field emission scanning electron microscopy (SEM) and X-ray diffraction (XRD) etc. The morphology of the MoS2/CuS nanohybrid is different from the MoS2 nanosheets and CuS nanoparticles. The hydrogen evolution reaction (HER) activity of MoS2 nanosheets, CuS nanoparticles and MoS2/CuS nanohybrid, were investigated by the Linear Sweep Voltammetry (LSV) and Tafel slope. The HER activity of MoS2/CuS nanohybrid is better than those of MoS2 nanosheets and CuS nanoparticles, which can be attributed to the good electron-transport ability of CuS and the strong reduction ability of hydrogen ions by MoS2. Thus, MoS2/CuS nanohybrid exhibited excellent activity for HER with a small onset potential of 0.15 V, a low Tafel slope of 63 mV dec?1, and relatively good stability. However, the MoS2 nanosheets and CuS nanoparticles respectively shows a bigger onset potential of 0.25 V and 0.35 V, a higher Tafel slope of 165 and 185 mV dec?1. This 3D flower-like heterostructure of MoS2/CuS nanohybrid catalyst exhibits great potential for renewable energy applications. 相似文献
93.
Nain Tara Mazhar Iqbal Qaisar Mahmood Khan Muhammad Afzal 《Water and Environment Journal》2019,33(1):124-134
This pilot study evaluated the effects of bacterial augmentation on the efficiency of floating treatment wetlands (FTWs) to remediate textile wastewater. Two wetland plants, Phragmites australis and Typha domingensis, were used to develop FTWs, which were then augmented with a bacterial consortium of three strains (Acinetobacter junii, Pseudomonas indoloxydans, and Rhodococcus sp.). Results showed that both plant species removed colour, organic matter, toxicity, and heavy metals from textile wastewater and their removal efficiency was further enhanced by augmentation with bacteria. The maximum removal efficiencies of colour, COD and BOD after an 8‐day period were 97, 87 and 92%, respectively, by FTWs carrying P. australis inoculated with the bacterial consortium. Furthermore, the same combination showed 87–99% reduction of heavy metals in the textile wastewater as well. These results indicate that FTWs can be used for the treatment of textile effluent and their working efficiency can be improved by plant‐bacterial synergism. 相似文献
94.
Abdul Rehman Yasin Muhammad Ashraf Aamer Iqbal Bhatti Ali Arshad Uppal 《Asian journal of control》2019,21(4):2074-2086
The rising cost of fossil fuels, their high depleting rate and issues regarding environmental pollution have brought the attention of the researchers towards renewable energy technologies. Different renewable energy resources like wind turbines, fuel cells and solar cells are connected to DC micro grid through controllable power electronic converters. In presence of these diverse generation units, robust controllers are required to ensure good power quality and to regulate grid voltage. This paper presents a sliding mode control based methodology to address the above mentioned challenges. The proposed technique keeps the switching frequency constant so that electromagnetic compatibility (EMC) issues can be solved with conventional filter design. Parallel operation of converter in DC micro gird is considered. Chattering reduction and power quality improvement by harmonic cancellation is proposed. A scaled down hardware for unregulated 11.5 V to 17.5 V input and 24V output is designed and tested. The experimental results show good performance of the controller under different loads and uncertain input voltage conditions. Moreover, the results show the robustness of the closed loop system to sudden variations in load conditions. Furthermore, a significant improvement in power quality is achieved by harmonic cancellation of chattering in the output of the converters. 相似文献
95.
Zeming Mu Qi Zheng Ruping Liu Muhammad Wasim Iqbal Malik Dongsheng Tang Weichang Zhou Qiang Wan 《Advanced Electronic Materials》2019,5(4)
Semiconductor heterostructure nanowires (HNWs) are excellent candidates for application in compact optoelectronics devices with high performance due to the heterojunction interface effect. However, the controllable fabrication of high‐quality nano‐heterostructures is elusive. In this paper, the controllable growth and optoelectronics device application of high‐quality ZnS0.49Se0.51/ZnSe axial HNWs are reported. The as‐synthesized HNWs are straight with uniform diameter distribution of 50–100 nm. Microstructural characterization reveals single crystal and abrupt heterojunction interface in these HNWs. The micro‐photoluminescence of single component region and heterojunction zone show one and integrated two near bandgap emission of ZnS0.49Se0.51 and ZnSe, respectively, further demonstrating the abrupt heterojunction interfaces nature in the as‐grown nanowires. Moreover, photodetectors based on single HNW are fabricated and the responsivity, external quantum efficiency, response speed, and detection wavelength range are superior to that of single component nanowire photodetectors at room temperature. These results show that the ZnS0.49Se0.51/ZnSe HNWs and corresponding high‐performance photodetectors are prospective candidates for photonics and optoelectronics applications. 相似文献
96.
Muhammad Iqbal Yusuf Valentino Kaneti Jeonghun Kim Brian Yuliarto Yong‐Mook Kang Yoshio Bando Yoshiyuki Sugahara Yusuke Yamauchi 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(6)
Palladium (Pd) plays an important role in numerous catalytic reactions, such as methanol and ethanol oxidation, oxygen reduction, hydrogenation, coupling reactions, and carbon monoxide oxidation. Creating Pd‐based nanoarchitectures with increased active surface sites, higher density of low‐coordinated atoms, and maximized surface coverage for the reactants is important. To address the limitations of pure Pd, various Pd‐based nanoarchitectures, including alloys, intermetallics, and supported Pd nanomaterials, have been fabricated by combining Pd with other elements with similar or higher catalytic activity for many catalytic reactions. Herein, recent advances in the preparation of Pd‐based nanoarchitectures through solution‐phase chemical reduction and electrochemical deposition methods are summarized. Finally, the trend and future outlook in the development of Pd nanocatalysts toward practical catalytic applications are discussed. 相似文献
97.
Muhammad Ali Raza Ling Yang Feng Wopke van der Werf Gao Ren Cai Muhammad Hayder Bin Khalid Nasir Iqbal Muhammad Jawad Hassan Tehseen Ahmad Meraj Muhammd Naeem Imran Khan Sana ur Rehman Muhammad Ansar Mukhtar Ahmed Feng Yang Wenyu Yang 《Food and Energy Security》2019,8(3)
Planting arrangements affect radiation use efficiency (RUE) and competitiveness of intercrop species in intercropping systems. Here, we reveal that narrow‐wide‐row planting arrangement in maize‐soybean relay‐intercropping system increases the dry matter and competitiveness of soybean, increased the RUE of maize and soybean, and compensates the yield loss of maize by substantially increasing the yield of soybean. In this field study, maize was planted with soybean in different planting arrangements (P1, 20:180, P2, 40:160; P3, 60:140, and P4, 80:120) of relay intercropping, all the relay‐intercropping treatments were compared with sole crops of maize (SM) and soybean (SS). Results showed that P1 improved the total RUE 3.26 g/MJ (maize RUE + soybean RUE) of maize and soybean in relay‐intercropping system. Compared to P4, treatment P1 increased the soybean competition ratio (CR) values (by 55%) but reduced the maize CR values (by 29%), which in turn significantly improved the yield of soybean by maintaining the maize yield. Generally, in P1, soybean produced 82% of SS yield, and maize produced 88% of SM yield, and it achieved the land equivalent ratio of 1.7. These results suggest that by maintaining the appropriate planting distances between maize and soybean we can improve the competitiveness and yield of intercrop species in relay‐intercropping system. 相似文献
98.
Amal Bouazizi Ghada Zaibi Amjad Iqbal Abdul Basir Mounir Samet Abdennaceur Kachouri 《国际射频与微波计算机辅助工程杂志》2019,29(8)
In this article, a novel 3D meandered planar inverted‐F antenna (PIFA) is proposed for dual band application targeting Wireless Body Area Network (WBAN). The proposed antenna is printed on the casing of a 3D‐base‐station model having a size of 88 × 95 × 10.2 mm3. The proposed PIFA covers two bands including medical implant communication service (MICS) (402‐405 MHz), as well as the industrial, scientific, and medical (ISM) (2.4‐2.48 GHz) bands. Each of the two bands can be controlled independently. The 3D configuration contains two linked meandered resonators to downsize the structure. Due to its conformal shape, omnidirectional radiation pattern, and low‐profile nature, the proposed PIFA is a potential candidate for targeting the WBAN applications. The proposed antenna, covering the MICS and ISM bands, works with an optimally matching (VSWR<2) at the aforementioned bands. The design concept was validated by fabricating the antenna prototype and measuring its characteristics. 相似文献
99.
Refined and deodorized rapeseed oil was hydrogenated using Girdler nickel catalyst at a starting temperature of 140 C and
at 25 and 30 psig hydrogen gas pressures. The studies revealed that the hydrogenation was more effective, as determined by
rate of decrease in iodine value (Wi js) and increase in the melting point, at 25 psig than at 30 psig. The rate of effectiveness
was, however, not significant. The rate of hydrogenation was compared to cottonseed oil subjected to hydrogenation under identical
conditions. Cottonseed oil showed a better, though insignificant, rate of increase in melting point per unit increase in time. 相似文献
100.
The occurrence of thermally stimulated currents in thin evaporated films of polypropylene was demonstrated and an analysis of the curves gave an electron trap depth of 0.33 eV in this material. 相似文献