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1.
Aniruddha Nag Mohammed Asif Ali Jiabei Zhou Makoto Ogawa Tatsuo Kaneko 《大分子材料与工程》2021,306(11):2100459
Aromatic and functional polymers with processibility derived from biobased starting materials are prerequisite considering sustainable society. Poly(2,5-benzimidazole)s are rigid-rod polymers to show ultrahigh thermal stability such as flame retardance, while usually suffer from poor solubility. Here, poly(benzimidazole-co-amide)s are synthesized from two biobased monomers, 3,4-diaminobenzoic acid and a semirigid comonomer, 4-aminohydrocinnamic acid. The copolymers with an amide composition of 80 mol% and higher are soluble in widely used polar solvents to fabricate the films keeping high flame retardance, which is comparable with popular high-performance polymers such as aromatic polyimides, polyetheretherketone, polyphenylene sulfide, etc. 相似文献
2.
Bukhari Muhammad Adnan Ahmad Zahoor Ashraf M. Yasin Afzal Muhammad Nawaz Fahim Nafees Muhammad Jatoi Wajid Nasim Malghani Naveed Aslam Shah Adnan Noor Manan Abdul 《SILICON》2021,13(12):4757-4772
Silicon - Feeling prone to stress differs with plant production stage, water scarcity near commencement of grain filling phase has a significant reduced grain yield through fewer endosperm and sink... 相似文献
3.
Mohammad Ali Mousavi Mahsa Baghban Salehi 《Polymer-Plastics Technology and Engineering》2021,60(1):47-59
ABSTRACT The hydrophobic polyether sulfone membranes were prepared by the sol-gel method to be applied in an air gap membrane distillation setup for desalination. The surface modifications were carried out using Trimethylsilyl chloride (TMSCl) and Methyltrimethoxysilane (MTMS) solutions. The membranes were characterized using Attenuated Total Reflection Infrared (ATR-IR) spectroscopy, Scanning Electron Microscopy (SEM), and Optical Contact Angle (OCA) methods. The effects of membrane preparation as well as operating conditions such as temperature difference, salt concentration, feed rotation speed, and cold-side temperature on membrane performance were investigated using central composite design method. It was found that feed temperature has the largest effect among the parameters on the permeation flux. The flow rate and salt rejection of the membrane in the optimum conditions were 4.47 Kg m?2 h?1 and 99.37%, respectively. 相似文献
4.
Iqbal Ahmad Syed Mujtaba Shah Muhammad Nadeem Zafar Muhammad Naeem Ashiq Wei Tang Uzma Jabeen 《Ceramics International》2021,47(3):3760-3771
Ferrites are materials of interest due to their broad applications in high technological devices and a lot of research has been focused to synthesize new ferrites. In this regard, an effort has been devoted to synthesize spinel Pr–Ni co-substituted strontium ferrites with a nominal formula of Sr1-xPrxFe2-yNiyO4 (0.0 ≤ x ≤ 0.1, 0.0 ≤ y ≤ 1.0). The cubic structure of pure and Pr–Ni co-substituted strontium ferrite samples calcinated at 1073 K for 3 h has been confirmed through X-ray diffraction (XRD). Average sizes of crystallites (18–25 nm) have been estimated from XRD analysis and nanometer particle sizes of synthesized ferrites have been further verified by scanning electron microscopy (SEM). SEM results have also shown that particles are mostly agglomerated and all the samples possess porosity. It has been observed that at 298 K, the values of resistivity (ρ) increase, while that of AC conductivity, dielectric loss, and dielectric constants decrease with increasing amounts of Pr3+ and Ni2+ ions. The values of dielectric parameters initially decrease with frequency and later become constant and can be explained on the basis of dielectric polarization. Electrochemical impedance spectroscopy (EIS) studies show that the charge transport phenomenon in ferrite materials is mainly controlled via grain boundaries. Overall, synthesized ferrite materials own enhanced resistivity values in the range of 1.38 × 109–1.94 × 109 Ω cm and minimum dielectric losses, which makes them suitable candidates for high frequency devices applications. 相似文献
5.
Kamyabi Mohammad Ali Moharramnezhad Mohsen 《Journal of Applied Electrochemistry》2021,51(10):1371-1385
Journal of Applied Electrochemistry - In this paper, a novel signal-off electrochemiluminescence sensor based on a ternary nanocomposite of ruthenium nanobeads/silver nanoparticles/graphene oxide... 相似文献
6.
Muhammad Atta Jatoi Abdul Sattar Mazari Shaukat Ali Abro Rashid Mubarak Nabisab Mujawar Ahmed Shoaib Shah Asif Memon Abdul Qayoom Akhter Faheem Wahocho Shafique Ahmed 《Journal of Porous Materials》2021,28(6):1945-1960
Journal of Porous Materials - Compared with traditional battery and super capacitor materials, nanomaterials can significantly improve ion transport and electron conductivity. There are many... 相似文献
7.
This study proposes a multiperiod mixed integer linear programming model for the management of a single municipal solid waste (MSW) treatment plant with sustainability as the objective. Discrete and continuous variables define the capacity selections for diverse MSW technologies, and the operation of the MSW network, respectively. The economic target is considered to maximize the net present value. The environmental impact is the minimization of a normalized environmental objective function (NEOF). The social target is the maximization of jobs. An interesting feature about the research work is the requirement of biodrying technologies for MSW moisture content control. Due to the conflicted nature among the sustainability components, a multiobjective optimization (MO) is carried out to find the Pareto optimal solutions. The MO results show that the Pareto optimal solutions vary around profit range of $4.9–8.5 billion, NEOF impact range of 3.2–3.6 units, and social benefit range of 2700–4828 jobs. 相似文献
8.
Silicon - A novel hybrid silicon Single Electron Transistor Metal Oxide Semiconductor (SETMOS) logic is evaluated for its functionality and usability. Emphasis is given on obtaining functionality... 相似文献
9.
Naser Hosseini Ali Fazili Mohammad Reza Derakhshandeh Leila Nikzad Milad Bahamirian Mansour Razavi 《Ceramics International》2021,47(11):15771-15782
In this study, the effect of Co addition on microstructural and mechanical properties of WC-B4C–SiC composites sintered by spark plasma sintering (SPS) method was investigated. For this purpose, three batches of WC-B4C–SiC with different contents of Co (10 vol%, 15 vol%, and 20 Vol %) were sintered at 1400 °C. The results of X-ray diffraction (XRD) analysis of the samples indicated the formation of W2B5, W3CoB3 as well as the remained C phases and unreacted SiC phase. It was observed that by increasing the Co content, the amount of W2B5 phase reduces and W3CoB3 and C contents increase. Therefore, W2B5 peaks were not detected in the sample containing 20vol% Co. Relative density values above 97% were obtained for all the composites. However, a decrease was observed in relative density by increasing the Co content in the composites. The highest flexural strength (510 ± 42 MPa), fracture toughness (10.34 ± 0.82 MPa m1/2), and hardness (20.63 ± 0.75 GPa) were also obtained for the sample containing 10vol% Co compared to the other samples. In addition, Transgranular fracture of SiC as well as pulling out of W3CoB3 and W2B5 particles were observed in the fracture surface micrographs of the samples. The presence of micro-cracks in the SiC grains, fracture of W3CoB3 grains, and crack deflection was reported as dominant toughening mechanisms. 相似文献