As an absolute method, which does not require standard substances to obtain the molecular weights of a specific polymer, the laser light scattering is an under-exploited method for study of polymers behavior in solution. Therefore, in this study, the variation of physico-chemical parameters in solution of polymers from poly(N-vinylcarbazole)/2, 2’, 4, 4’,-tetranitrodibenzyl (PVK-TNDB) and poly(N-ethyl-3-hydroxymethyl phenothiazinyl methacrylate)/poly(β,-hydroxyethyl-3, 5-dinitrobenzoate methacrylate) (PEHMPtM-PHEDNBM) systems was analyzed by multiangle laser light scattering (MALLS) and correlated with their ability to interact by charge transfer (CT). The confirmation of charge transfer interactions even in solid state was realized by atomic force microscopy (AFM) or differential scanning calorimetry studies (DSC). In case of PVK-TNDB mixtures, two variants for approximation of experimental MALLS data were tested. The Zimm plot and Berry formalism were used, but first-or second-order fitting of the experimental data by scattering angles, θ, , were compared. In both cases, the maximum values of weight averaged molecular weight, M¯, ¯, ¯, ¯, ¯, w�, ¯, �, , and radius of gyration, Rg, for polymer were recorded for 1/1 molar ratio, even that with the second-order fitting these values were overestimated. In solid state, the AFM imaging has shown good compatibility between PVK and TNDB based on charge transfer interactions, preserved after solvent evaporation. In case of PEHMPtM–, PHEDNBM mixtures, the maximum number of CT interactions was established for equimolar ratio of components both in solution, where a maximum value for weight average molecular weight and in solid state for glass transition temperature, respectively were foud.

Foodborne bacteria pose substantial risks to human health and food safety. Scientists worldwide have shown great interest in the development of rapid, reliable, and cost-effective methods for identifying foodborne bacteria. Among these methods, Optical scattering technology (BARDOT) has emerged as the fastest and most efficient technique, offering a unique pattern of scattered light passing through the center of the bacterial colony for identification purposes. In this study, we examined 118 isolates of foodborne pathogenic bacteria, including Escherichia coli, Enterobacter cloacae, Salmonella Enterica, Hafnia alvei, and Proteus mirabilis, derived from various food sources. To identify these isolates, we employed Analytical Profile Index (API) Systems, specifically API 20E and ID 32E, which rely on biochemical tests, in addition to laser light scattering technology. In this method ideal colonies, which exhibited specific characteristics such as a suitable diameter, isolation from neighboring colonies, and a completely circular shape without any irregular edges, were selected to create scatter images. These scatter images revealed a distinct "fingerprint" that can be utilized to differentiate between the species. This "fingerprint" allowed for the successful identification of all isolates belonging to the five species in our current study, achieving a 100% identification accuracy. Our findings demonstrated that laser light scattering technology provided accurate identification cost-effectively and safely. This method eliminated the need to open the plates containing the bacterial colonies, ensuring the colonies remained intact after identification. Furthermore, the laser light scattering technique proved to be much more rapid compared to the API 20E and ID 32E Systems, which were not only significantly more expensive but also time-consuming and labor-intensive.

In this paper, the optical properties of gold nanoparticles investigated. For this purpose the scattering intensity of a laser beam incident on gold nanoparticles has been studied using Mie theory and their respective curves versus different parameters such as scattering angle, wavelength of the laser beam and the size of gold nanoparticles are plotted. Investigating and comparison of the depicted plots show that the scattering intensity increases with increasing gold nanoparticles size up to 100 nm and further increasing of nanoprticles sizes leads to oscillating like behavior in the intensity patterns. Several peaks emerges in the patterns of intensity versus nanoparticle size. It was also found that for particles with sizes less than 100 nm the intensity patterns versus wavelength had a one peak about 520 nm while for the particles bigger than 100 nm there appears other maxima in different wavelength too. Changing the angle of scattering led to change in the intensity pattern of scattered light and its minimum value was detected at 90o. These results can be used in detecting cancerous tumors and in cancer therappy.

Background: Producing the ideal therapeutic electron beams from a clinical linear accelerator (Linac), is crucial to optimize dose delivery in radiotherapy. The aim of this study was to investigate the properties of electron beams with and without the scattering foil. Materials and Methods: Varian Linac 2100CD head was simulated by means of MCNPX-2. 7 program. After validation with measured data, scattering foils were removed and then different dosimetric properties of 6 and 9 MeV electron beams such as depth dose percentage, dose profile, range, surface dose, dose rate and photon contamination were calculated and compared for field sizes ranging from 0. 25×0. 25 to 10×10 cm2 in three states with primary and secondary scattering foil (SF), without primary scattering foil (PSFF) and without primary and secondary scattering foil (SFF). Results: By removing the scattering foils, dose rates and surface doses were increased more than 25 times in 0. 25×0. 25 cm2 field, and in the bigger fields, it was less in 10×10 cm2 field, almost 4 times and the photon contamination is reduced by 20% times in 0. 25×0. 25 cm2 field. Also, Adjacent organs receive a lower dose, Because the dose profile curve was shrieked, it was almost 1cm in field 2×2 cm2 and less than 1cm in other fields. The dose profile flatness was diminished in scattering foil-free (SFF) mode which is not crucial for the small fields. Conclusion: Removing scattering foil improves dosimetric properties of electron beams specially to treat the superficial tumors and for the small field radiotherapy.