A series of cadmium sulfide materials have been prepared using microwave-assisted hydrolysis of cadmium-thiourea complexes in water and nonaqueous solvents. Materials are characterized using X-ray diffraction, scanning electron microscopy, diffuse reflectance spectroscopy, and various photoelectrochemical techniques. Sulfur-doped samples of CdS exhibit a pronounced photoelectrochemical photocurrent switching effect within low-energy tails of their absorption spectra. A mechanism of the photocurrent switching process is presented on the basis of experimental investigations and quantum-chemical calculations.

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One of the most common methods of carbon nanotubes (CNTs) synthesis is application of an electric-arc plasma. However, the final product in the form of cathode deposit is composed of carbon nanotubes and a variety of carbon impurities. An assay of carbon nanotubes produced in arc discharge systems available on the market shows that commercial cathode deposits contain about 10% CNTs. Given that the quality of the final product depends on carbon–plasma jet parameters, it is possible to increase the yield of the synthesis by plasma jet control. Most of the carbon nanotubes are multiwall carbon nanotubes (MWCNTs). It was observed that the addition of catalysts significantly changes the plasma composition, effective ionization potential, the arc channel conductance, and in effect temperature of the arc and carbon elements flux. This paper focuses on the influence of metal components on plasma-jet forming containing carbon nanotubes cathode deposit. The plasma jet temperature control system is presented.

In this paper, a novel approach to the synthesis of the carbon nanotubes (CNTs) in reactors operating at atmospheric pressure is presented. Based on the literature and our own research results, the most effective methods of CNT synthesis are investigated. Then, careful selection of reagents for the synthesis process is shown. Thanks to the performed calculations, an optimum composition of gases and the temperature for successful CNT synthesis in the CVD (chemical vapor deposition) process can be chosen. The results, having practical significance, may lead to an improvement of nanomaterials synthesis technology. The study can be used to produce CNTs for electrical and electronic equipment (i.e., supercapacitors or cooling radiators). There is also a possibility of using them in medicine for cancer diagnostics and therapy.

Medium molecular weight poly(L,L-lactide)s (PLA) containing at one chain end ionic group derived from imidazolium ionic liquid (IL) were synthesized by cationic polymerization using hydroxylated IL as initiator. matrix assisted laser desorption/ionization time-of-flight analysis confirmed the structure of products (PLA-IL). Carbon nanotubes (CNT) were dispersed in solution of PLA-IL in 1,4-dioxane and significant improvement of stability of suspension was observed by measurements of suspension absorbance. Similar effect was, however, observed also for solutions of PLA which did not contain terminal IL group. CNT samples treated with PLA-IL and PLA were isolated, thoroughly washed with 1,4-dioxane and stability of suspensions was again measured. Sample treated with PLA after washing behave similarly to untreated CNT. Stability of suspension of CNT treated with PLA-IL after washing was considerably higher than that of untreated CNT and the presence of polymer bound to CNT was clearly detectable in scanning electron microscopy images. Results indicate that there is indeed an interaction between end-group derived from IL and CNT surface as postulated earlier but to observe solely this effect an excess of polymer should be removed, otherwise factors such as increase of viscosity of solution or weak interactions of PLA ester groups with CNT may obscure results.

In this study, three independent methods were used to identify short fragment of both chains of human insulin which are prone for aggregation. In addition, circular dichroism (CD) research was conducted to understand the progress of aggregation over time. The insulin fragments (deca- and pepta-peptides) were obtained by solid-phase synthesis using 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium toluene-4-sulfonate (DMT/NMM/TosO-) as a coupling reagent. Systematic studies allowed identification of the new fragments, expected to be engaged in triggering aggregation of the entire structure of human insulin under physiological conditions. It was found that the aggregation process occurs through various structural conformers and may favor the formation of a fibrous structure of aggregate.

Despite the development of pharmacy, there are still incurable diseases for which the medicine has not been found yet. Because many diseases are asymptomatic in their first stage of development, often early detection is the crucial factor in combating them. The article describes the process of synthesis of carbon nanotubes (CNTs) which can be useful in medical diagnostics. CNTs were synthesized by chemical vapor deposition. The obtained material was subjected to functionalization – attaching fluorescent markers. In order to check the usefulness of the obtained structures in diagnostics, their fluorescent properties were examined. The results of fourier transform infrared spectroscopy thermogravimetric analysis and scanning electron microscopy prove that, after proper functionalization, CNTs could be used as fluorescents markers.