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Carbon nano fibers (CNFs) were synthesized at high temperature using natural linseeds oil.

There are enormous methods such as physical, chemical, and biological, for the synthesis of metallic nanoparticles (MNPs), which has become a matter of focus among material scientists. Green chemistry-based MNP synthesis is an area, which has gained much importance presently due to their non-toxicity and monodispersed nanoparticle preparation methodologies. Among green synthesis methods, plants are considered as efficient candidates for nanoparticle synthesis. The meticulous formation of different sizes and shapes of the nanoparticles using plants has spurred encouraging interest. The rate kinetics and stability of nanoparticle synthesis are well studied as well as appreciated in the arena of materials. Their capability to sequester metal ions and fastidiously define the dimensions using a plethora of capping proteins such as glutathione and phytochelatins is intriguing giving it a monodispersed size. This review is a comprehensive understanding of the metal nanoparticles synthesized by plants and apprehends the mechanism of nanoparticle synthesis exhaustively.

In radiochemical work, our interests are to identify the isotope, as well as measure the activity accurately present in the sample.

This chapter is devoted to discussing a few special types of counters and techniques for the measurement and detection of radioactive isotopes present in either small quantity (for example, radioactivity present in food and measurement of activity slightly greater than background activity or low activity of \(\alpha \)-particulate radiation).

In the previous chapter, we realized the importance of source preparation for getting meaningful results. However, in addition to source preparation, there are many other factors, like geometrical factors, scattering of radiation, selection of radiation emitted by the isotope etc., that also need to be considered for measuring the activity of the radioactive sample. It is necessary to consider these factors, especially when an absolute count rate is required. In this chapter, we shall discuss these factors to a greater depth.

Radioactive nuclides separated by any radiochemical techniques will probably need to be counted. The separated material cannot be simply put near the counter and counted. A special technique is required to prepare a suitable source for counting. In this chapter, various modes under which a radioactive material can be counted and importance of source preparation for counting activity of the radioactive sample is presented.

There are many good books dealing with Nuclear chemistry but very few deal with nuclear reactions which can be of interest to chemists, especially the effect of nuclear transformation on the chemical nature of the product formed during a nuclear reaction. In this chapter, we shall mainly be discussing this type of nuclear reaction.

Practically every book on radiochemistry deals with the statistics of numbers and it will be beyond the scope of this book to deal with this subject in much detail.

In this chapter, efforts are made to give a brief outline of a few techniques, which are routinely followed in radiochemical experiments. It is important to realize that in radiochemical separation techniques, emphasis is given to the purity of radioactive material and not much to their chemical purity. This is mainly because the amount of activity is measured with the help of the various radiations emitted by the radioactive isotopes.

While handling radioactive isotopes, mere knowledge of radiochemical techniques to perform some specific chemical reaction/separation, or to detect, measure the activity etc., are not enough. It is equally important to be aware of the health hazards associated with radioactive isotopes. Moreover, it is also important to realize that the laboratory where such work is expected to be carried out, should take care of the disposal and contamination problems associated with some of the hazardous radioactive isotopes like \(^{137}\)Cs.

Castor seeds are non-edible oil rich plant product, with many medicinal properties. Carbon nano flakes being a new type carbon material were synthesized from castor seeds (as biological precursor) by single zone CVD method. During pyrolysis, Argon gas was used as a carrier gas, and temperature was maintained 8000C for an hour. Scanning Electron Microscopic (SEM) images confirmed the morphology of nano sized carbon flakes along with some nano-carbon fragments while XRD peaks showed the crystallinity of the carbon nano flake and RAMAN spectra of obtained carbon nano flakes revealed the presence of defects on its surface thus confirming its amorphous nature.

Carbon dots (C-dots) are one of the most highlighted carbon-based materials for biological applications such as delivery of therapeutic payloads for cancer treatment mainly due to their biocompatibility and unique optical properties. In this work, we have explored the drug carrying capacity of highly fluorescent sorbitol-derived C-dots for targeted delivery of doxorubicin (DOX). We have used folic acid (FA) as a navigational molecule due to its high expression in most cancer cells. Before attachment of the DOX, the surfaces of the C-dots were protected with bovine serum albumin (BSA) to make them more biocompatible and able to hold a high amount of drugs. The release profile of DOX was studied using standard statistical models and confirmed to be first order at pH 7.2. Cellular imaging was performed using epifluorescence microscopy, which showed bright green coloured fluorescence due to internalization of C-dots specifically targeted with FA in HeLa cells.

Azadirachta indica as a biological sink for fabrication of gold nanoparticles (GNPs) and its applications in efficient delivery of doxorubicin (DOX) are presented here. Sucrose density gradient centrifugation was used to isolate the spherical GNPs of

Correction for ‘CNFs from linseeds oil: a potential source of X-band microwave absorbers’ by Dattatray E. Kshirsagar et al., Mater. Adv., 2022, DOI: https://doi.org/10.1039/d1ma01252e.

This review encompasses properties and applications of polycrystalline or amorphous, Transparent Conducting Oxides (TCO) semiconductors. Coexistence of electrical conductivity and optical transparency in TCO depends on the nature, number and atomic arrangements of metal cations in oxides, on the resident morphology and presence of intrinsic or introduced defects. Therefore, TCO semiconductors that are impurity-doped as well as the ternary compounds and multi-component oxides consisting of combinations are discussed. Expanding use of TCO is endangered by scarcity, cost of In, fragility of glass, limited transparency to visible light, instability above >200 °C, non-flexible for application of flexible solar cell; thus driving search for alternatives such as graphene or CNT, that are more stable under acidic, alkaline, oxidizing, reducing and elevated temperature. There are reasons to conclude that there is need to develop large area deposition techniques to produce TCO films with high deposition rate. TCOs are mostly n-type semiconductors, but p-type are also being researched

Chain of carbon micro beads (CMBs) molded by interconnection of micro carbon beads were synthesized using pyrolysis of brassica nigra oil vapour at 850 °C in hydrogen atmosphere. Return loss and conductivity of arbitrarily oriented CMBs film reveals ability as a potential microwave absorber in 8 to 12 GHz range with return loss between −21 dB to −30 dB. Study of electrical resistance and EMI shielding effectiveness (SE) shows that CMBs films also has competency to obstruct the passage of microwave frequency with shielding effectiveness of −29 dB to −45 dB.

An economical green-chemistry approach was used for the synthesis of aqueous soluble graphene quantum dots (GQDs) from cow milk for simultaneous imaging and drug delivery in cancer. The GQDs synthesized using one-pot microwave-assisted heating were multi-fluorescent, spherical in shape having a lateral size of ca. 5 nm. The role of processing parameters such as heating time and ionic strength showed a profound effect on photoluminescence properties of GQDs. The GQDs were N-doped and oxygen-rich as confirmed by X-ray photoelectron spectroscopy (XPS) analysis. Cysteamine hydrochloride (Cys) was used to attach an anti-cancer drug berberine hydrochloride (BHC) on GQDs forming GQDs@Cys-BHC complex with c.a. 88% drug loading efficiency. In vitro drug release was studied at the acidic-basic environment and drug kinetics was studied using pharmacokinetic statistical models. The GQDs were biocompatible on L929 cells whereas theranostic GQDs@Cys-BHC complex showed a potent cytotoxic effect on different cancerous cell line models: cervical cancer cell lines such as HeLa cells and breast cancer cells such as MDA-MB-231 confirmed by Trypan blue and MTT-based cytotoxic assays. Furthermore, multi-excitation based cellular bioimaging was demonstrated using confocal laser scanning microscopy (CLSM) and fluorescence microscopy using GQDs as well as GQDs@Cys-BHC complex. Thus, drug delivery (therapeutic) and bioimaging (diagnostic) properties of GQDs@Cys-BHC complex are thought to have a potential in vitro theranostic application in cancer therapy.

Corn cob, an agricultural waste, is paralyzed at different temperatures (700oC, 800oC and 900oC). Microwave absorption of carbon in the frequency range of 2 GHz to 8 GHz is reported. Carbon activated  with 5% nickel nitrate showed more than 90% absorption of microwave in the frequency range from 6 GHz to 8 GHz, while carbon activated  with 10% Nickel nitrate treated corn cob showed 90% absorption in the frequency range of 2.5 GHz to 5 GHz. Carbon showing the best absorption are characterized by XRD, Raman spectra and SEM . It is suggested that corn cob treatment  alone with KOH did not improve the microwave absorption, whereas treatment along with nickel nitrate improved the absorption property much better. It is proposed that treatment with nickel nitrate helps in creating suitable pores in carbon  which improved the absorption behavior because while treating carbon with 1N HCl helps to leach out nickel creating equivalent amount of pores in the carbon.

Thin film of carbon was synthesized from camphor (C10H16O) by CVD technique in hydrogen atmosphere. For the first time it is confirmed the presence of almost zero indirect band gap in addition to its direct band gap.. Carrier concentration with intrinsic carbon is found to be around 1021 n/cm3. It is suggested that unless the zero indirect band gap is  increased carbon thin film   cannot be used for making a p:n junction. XRD, Raman and SEM analysis are performed.

Titanium dioxide or Titania is a semiconductor compound having remarkable dielectric, electronic and physico-chemical surface properties. It has excellent photocatalytic efficiency in presence of UV light. The curious grey matter of scientists has forced them to focus their attention to make Titania capable of utilizing the whole visible spectrum of light also. The hurdle that they faced was larger band gap of 3 eV and more, for this, efforts were directed towards adding other materials to Titania. The present article reviews the recent advances in the synthesis of different Titanium-based nanocomposite materials and their photocatalytic efficiency so as to apply them for several applications such as removal of dyes, other water pollutants, microbes and metals. A brief explanation of the photocatalytic process and the structural properties of TiO2 are also touched upon. Various past and recent approaches made in these directions of utilizing Titania based nanocomposites for photocatalytic activities are reviewed. It is suggested that there is a need to establish the kinetics of photo-corrosion and thermodynamic part of the photo-corrosion of various composites developed by different group across the globe, so that Titania based nanocomposites could be commercially utilized.

In this paper hydrogen adsorption capacity of carbon fibers is presented. These fibers are synthesized by pyrolysis of cotton fibers. Forty five varying parameters are applied for the pyrolysis of cotton to get carbon fiber of varied specific densities. Specific densities are calculated by (i) water displacement method and (ii) tapping method. Maximum hydrogen adsorption capacity is found to be 1.246 wt% if specific density value obtained by water displacement method is considered; whereas specific density obtained from tapping method showed 7.076 wt% hydrogen adsorption by the same carbon fibers. This paper imposes a question that since the measurement of density of carbon by these two method give different results which one should be accepted or is there a need to develop another method.