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101.
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A cauliflower-like ternary nanocomposite of poly(3,4-ethylenedioxythipohene)/nanocrystalline cellulose/manganese oxide (PEDOT/NCC/MnO2) was synthesized using one-step electropolymerization technique. The effect of manganese (Mn) concentration on the supercapacitive performance was investigated. The structural and morphology studies were conducted using field emission scanning electron microscope, Fourier transform infrared spectroscopy, Raman spectroscopy, and X-ray diffraction. The morphology of ternary nanocomposite at an optimized concentration of Mn resembles the cauliflower-like structure. The two-electrode electrochemical analysis of a ternary nanocomposite PEDOT/NCC/MnO2 exhibited a higher specific capacitance of 144.69 F/g at 25 mV/s in 1.0 M potassium chloride compared to PEDOT/NCC(63.57 F/g). PEDOT/NCC/MnO2 ternary nanocomposite was able to deliver a specific power of 494.9 W/kg and 10.3 Wh/kg of specific energy at 1 A g−1 and retained 83% of initial capacitance after 2,000 cycles. These promising results from the incorporation of Mn displayed great prospective in developing PEDOT/NCC/MnO2 as an electrode material for supercapacitor.  相似文献   
103.
Sense codon recoding is the basis for genetic code expansion with more than two different noncanonical amino acids. It requires an unused (or rarely used) codon, and an orthogonal tRNA synthetase:tRNA pair with the complementary anticodon. The Mycoplasma capricolum genome contains just six CGG arginine codons, without a dedicated tRNAArg. We wanted to reassign this codon to pyrrolysine by providing M. capricolum with pyrrolysyl‐tRNA synthetase, a synthetic tRNA with a CCG anticodon (${{\rm tRNA}{{{\rm Pyl}\hfill \atop {\rm CCG}\hfill}}}$ ), and the genes for pyrrolysine biosynthesis. Here we show that ${{\rm tRNA}{{{\rm Pyl}\hfill \atop {\rm CCG}\hfill}}}$ is efficiently recognized by the endogenous arginyl‐tRNA synthetase, presumably at the anticodon. Mass spectrometry revealed that in the presence of ${{\rm tRNA}{{{\rm Pyl}\hfill \atop {\rm CCG}\hfill}}}$ , CGG codons are translated as arginine. This result is not unexpected as most tRNA synthetases use the anticodon as a recognition element. The data suggest that tRNA misidentification by endogenous aminoacyl‐tRNA synthetases needs to be overcome for sense codon recoding.  相似文献   
104.
The tremendous increase in human population and industrialization has exacerbated the existing problem of water pollution to a great extent. The textile industry is the major cause of this problem due to its significant use of organic synthetic dyes as coloring materials during the dyeing process. The presence of color in wastewater is a major environmental concern, as these dyes are resistant to degradation by physio-chemical treatments. Bioremediation is an attractive method that can completely degrade these dyes while also being cost-effective. This comprehensive review aims to provide a brief insight into bioremediation based on some of the latest emerging wastewater treatment technologies for the removal of synthetic dyes. Starting with the importance of decolorization of synthetic dyes and their environmental impacts, different physio-chemical treatment technologies are analyzed with a special emphasis on their limitations. The bioremediation of textile wastewater with detailed biodegradation mechanisms using different bacterial species (bacteria, fungal, algae, enzyme, and mixed culture) under aerobic and anaerobic conditions is thoroughly discussed. In this article, the major factors affecting the implementation of biological treatment are explained. In addition, the latest emerging treatment technologies, such as nano-bio materials, genetic engineering, phytoremediation, electro-bioremediation (microbial electrochemistry technology, MET), and integrated/hybrid technologies (such as biological processes with physio-chemical processes, electro-coagulation, adsorption, ultra-filtration, membrane, and advanced oxidation) are critically reviewed; their challenges and the future perspectives in textile wastewater treatment are also highlighted. © 2021 Society of Chemical Industry (SCI).  相似文献   
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Kulkarni GU  Radha B 《Nanoscale》2010,2(10):2035-2044
Metal nanowire patterning in the form of grating structures has been carried out using a wide range of lithography techniques, and many hybrid methods derived from them. The challenge is to achieve sub-100 nm linewidths with controllable spacing and thickness over large areas of substrates with high throughput. In particular, the patterns with linewidth and spacing of a few tens of nm offer properties of great interest in optoelectronics and plasmonics. Crossbar grating structures--two gratings patterned perpendicular to each other--will play an important role as ultra-high density electrode grids in memristive devices for non-volatile memory.  相似文献   
107.
A simple, one‐step process to synthesize Pd4S films is reported here along with their characterization using X‐ray diffraction, electron microscopy, and electrical measurements. The synthesis involves thermolysis of a single‐source precursor, namely palladium alkanethiolate, in H2 atmosphere at 250 °C for 3 h. The films are highly conducting and resistant to strong acidic, alkali, and oxidizing environments. The precursor allows patterning of the Pd4S films by electron beam lithography and micromolding, an attribute that has been employed in making chemically resistant electrodes and etch masks. The conversion of palladium thiolate to other sulfide phases is also achieved.  相似文献   
108.
Different amounts of Co-doped TiO2 powders and thin films were prepared by following a conventional co-precipitation and sol–gel dip coating technique, respectively. The synthesized powders and thin films were subjected to thermal treatments from 400 to 800 °C and were thoroughly investigated by means of X-ray diffraction, X-ray photoelectron spectroscopy, energy dispersive analysis with X-rays, FT-infrared, FT-Raman, diffuse reflectance spectroscopy, ultraviolet–visible spectroscopy, BET surface area, zeta potential, flat band potential measurements, band-gap energy, etc. The photocatalytic ability of the powders was evaluated by methylene blue (MB) degradation studies. The thin films were characterized by photocurrent and ultraviolet–visible (UV–Vis) spectroscopy techniques. The characterization results suggest that the Co-doped TiO2 powders synthesized in this study consist mainly anatase phase, and possess reasonably high specific surface area, low band gap energy and flat band potentials amenable to water oxidation in photoelectrochemical (PEC) cells. The photocatalytic degradation of MB over Co-doped TiO2 powders followed the Langmuir–Hinshelwood first order reaction rate relationship. The 0.1 wt.% Co-doped TiO2 composition provided the higher photocurrent, n-type semi-conducting behavior and higher photocatalytic activity among various Co-doped TiO2 compositions and pure TiO2 investigated.  相似文献   
109.
Cloud computing (CC) is an advanced technology that provides access to predictive resources and data sharing. The cloud environment represents the right type regarding cloud usage model ownership, size, and rights to access. It introduces the scope and nature of cloud computing. In recent times, all processes are fed into the system for which consumer data and cache size are required. One of the most security issues in the cloud environment is Distributed Denial of Service (DDoS) attacks, responsible for cloud server overloading. This proposed system ID3 (Iterative Dichotomiser 3) Maximum Multifactor Dimensionality Posteriori Method (ID3-MMDP) is used to overcome the drawback and a relatively simple way to execute and for the detection of (DDoS) attack. First, the proposed ID3-MMDP method calls for the resources of the cloud platform and then implements the attack detection technology based on information entropy to detect DDoS attacks. Since because the entropy value can show the discrete or aggregated characteristics of the current data set, it can be used for the detection of abnormal data flow, User-uploaded data, ID3-MMDP system checks and read risk measurement and processing, bug rating file size changes, or file name changes and changes in the format design of the data size entropy value. Unique properties can be used whenever the program approaches any data error to detect abnormal data services. Finally, the experiment also verifies the DDoS attack detection capability algorithm.  相似文献   
110.
Journal of Materials Science: Materials in Electronics - Solid polymer electrolytes (SPE) are an important field of research. Creation of environmentally friendly SPEs is essential. In this...  相似文献   
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