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Fine bamboo strips (BSs) have been laid on polypropylene (PP) web, stacked, and compression molded to prepare unconsolidated light-weight (0.312 g/cm3) composites. Composite properties are superior compared with jute-based composites and bamboo strips show potential to replace fiberglass or polyurethane in composites. Flexural strength, modulus, offset yield load, and Noise Reduction Coefficient (NR) of the BS–PP composites are 5.8×, 2.9×, 6.5×, and 1.4× higher, respectively, compared to jute–PP composites. Bamboo-based non-consolidated composites with excellent mechanical and sound absorption properties utilizing the methods described in this research provide an opportunity to manufacture functional composites with bio-based materials leading to reduction of environmental pollution and sustainable manufacturing. 相似文献
34.
Suman Devi Prakash Korake S.N. Achary Narendra M. Gupta 《International Journal of Hydrogen Energy》2014
A series of CdS/Nix nanocomposite photocatalysts, containing ca. 0.6–15 wt% Ni, were synthesized using a one-step hydrothermal method and characterized for their crystallographic, morphological, interfacial, and optical properties. Rietveld refinement of powder XRD data revealed the coexistence of wurtzite (hexagonal) and zinc blende (cubic) phases of CdS in ratios dependent on Ni content. Only a fraction of Ni existed as a secondary phase of NiS while the majority occupied the lattice positions of hexagonal CdS. Whereas up to 10-fold enhancement in H2 evolution compared with pure CdS was observed for samples containing ∼1.5–4.5 wt% Ni, samples with smaller or larger Ni content displayed poor activity for visible-light-induced splitting of water in presence of sulfide–sulphite ions as sacrificial electron donors. In contrary to recent findings, our study reveals that the enhanced CdS photoactivity is not a result of charge transfer between p-type NiS and n-type CdS, Ni-induced visible-region absorbance, or the coating of CdS particles by non-photoactive NiS. Instead, the preparation-dependent hexagonal/cubic CdS phase boundaries and particle morphology may play a crucial role. Additionally, certain Ni-doping-induced sub-bandgap shallow energy levels contribute to charge carrier separation. 相似文献
35.
S. K. Bajpai Pradeep Daheriya Sonam Ahuja K. Gupta 《Designed Monomers and Polymers》2016,19(7):630-642
In the present study, poly(vinyl alcohol) (PVA)/Carrageenan(Car) composite films have been prepared by ionic cross-linking of the two polymers with Borax (Bx) and K+ ions, respectively, in aqueous medium at room temperature. The films were characterized by FTIR, SEM, TGA, and AFM analysis. The equilibrium percent swelling (EPS) of PVA/Carr films, so produced, exhibited negative dependence on the amount of cross-linkers. A detailed investigation of their water absorption and moisture permeation behavior has been carried out. The films showed non-thrombogenic and non-cytotoxic behaviors. Finally, drug minocycline-loaded films showed excellent antimicrobial behavior. 相似文献
36.
Hang Liu Xiaofeng Zhao Yuancheng Teng Yuxiang Li Xiayu Zheng Shanlin Wang Lang Wu Pritam Kumar Panda Rajeev Ahuja 《Journal of the American Ceramic Society》2022,105(7):4974-4985
LnPO4 · 0.667H2O rhabdophane has been considered as a potential material for the precipitation of actinides from radioactive waste liquid, owing to its outstanding characteristics of high actinide bearing and easy synthesis in acid solutions. However, a comprehensive understanding of the actinide occupation and the precipitation response of rhabdophane to remove actinides has yet to be established. In this study, the effect of ions concentration and pH values on the detailed precipitation reaction of CexNd1-xPO4 · 0.667H2O rhabdophane in acid solutions are systematically investigated. Some specific issues such as structural distortion and flexibility, and occupation mechanism are discussed by combining with experiments and density functional theory (DFT) calculation. The results reveal that ions concentration and pH values have a significant impact on the crystallization nucleation step before 12 h. The obtained removal rate of Nd3+ is more than 99% in pH 1–5 solutions with the ions concentration of 0.05–0.1 mol/L. Moreover, incorporating Nd in CePO4 · 0.667H2O rhabdophane will easily result in the lattice distortion in b-axis. DFT calculation and X-ray photoelectron spectroscopy (XPS) results reveal that Nd is preferentially incorporated in nonhydrated site to form a weaker binding energy of NdO8 polyhedron. 相似文献
37.
Sravani Sadhu Satya Balaji B. Rao K. Srinivasa Babu A. Narendra Aditya M. Sravani K. Girja 《SILICON》2022,14(15):9263-9273
Silicon - Tunnel Field Effect Transistor (TFET) has become one of the promising devices to be part of Integrated circuits as the technology advances to the nanoscale. A TFET has many advantages... 相似文献
38.
Flow and temperature patterns in an inductively coupled plasma reactor: Experimental measurements and CFD simulations 下载免费PDF全文
Sangeeta B. Punjabi Sunil N. Sahasrabudhe S. Ghorui A. K. Das Narendra K. Joshi Dushyant C. Kothari Arijit A. Ganguli Jyeshtharaj B. Joshi 《American Institute of Chemical Engineers》2014,60(10):3647-3664
Measurements of temperature patterns in an inductively coupled plasma (ICP) have been carried out experimentally. Plasma torch was operated at different RF powers in the range of 3–14 kW at near atmospheric pressure and over a wide range of sheath gas flow rate (3–25 lpm). Measurements were made at five different axial positions in ICP torch. The chordal intensities were converted into a radial intensity profile by Abel Inversion technique. Typical radial temperature profile shows an off‐axis temperature peak, which shifts toward the wall as the power increases. Temperatures in the range of 6000–14,000 K were recorded by this method. The temperature profiles in the plasma reactor were simulated using computational fluid dynamics (CFD). A good agreement was found between the CFD predictions of the flow and temperature pattern with those published in the literature as well as the temperature profiles measured in the present work. © 2014 American Institute of Chemical Engineers AIChE J, 60: 3647–3664, 2014 相似文献
39.
Dendrimers are novel three dimensional, hyperbranched globular nanopolymeric architectures. Attractive features like nanoscopic size, narrow polydispersity index, excellent control over molecular structure, availability of multiple functional groups at the periphery and cavities in the interior distinguish them amongst the available polymers. Applications of dendrimers in a large variety of fields have been explored. Drug delivery scientists are especially enthusiastic about possible utility of dendrimers as drug delivery tool. Terminal functionalities provide a platform for conjugation of the drug and targeting moieties. In addition, these peripheral functional groups can be employed to tailor-make the properties of dendrimers, enhancing their versatility. The present review highlights the contribution of dendrimers in the field of nanotechnology with intent to aid the researchers in exploring dendrimers in the field of drug delivery. 相似文献
40.
S. Narendra Babu A. Siddeshwar K. Srinivas S. V. Suryanarayana T. Bhimasankaram 《Journal of Materials Science》2009,44(15):3948-3951
A composite material when placed under the external magnetic/electric fields exhibits voltage/induced magnetization is known
as magnetoelectric (ME) composite. Such composite materials should have ferroelectric and ferro/ferri magnetic phases as constituents.
The magnetoelectric output is exhibited as a product property. Magnetoelectric composites are being used for variety of applications
including resonators, filters, phase shifters, optical isolators, actuators and magnetic field sensors. Metal/ferroelectric/metal
magnetoelectric composite using Ni and PZT as constituent phases has been fabricated in 2-2 composite pattern to study its
product property. The paper presents magnetoelectric studies of Ni/PZT/Ni composite using low dc magnetic field magnetoelectric
set-up. Using this ME set-up ME output of Ni/PZT/Ni composite is studied as a function of dc magnetic field. The results were
analyzed to identify the useful magnetic field (dc and ac) range in which Ni/PZT/Ni sensor can be utilized for applications. 相似文献