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Biodiesel telah menjadi sumber energi alternaltif yang terus dikembangkan. Pada penelitian ini telah dilakukan sintesis biodiesel dari minyak ampas tahu menggunakan katalis lempung termodifikasi Kalsium Oksida (CaO) dengan pemanasan microwave untuk menghasilkan biodiesel. Sintesis Katalis lempung termodifikasi CaO menggunakan metode impregnasi basah. Sistesis biodiesel dari minyak ampas tahu melalui reaksi transesterifikasi dengan variasi jumlah katalis lempung termodifikasi CaO 1, 2, 3, 4, 5 % (b/b) dan variasi daya microwave 150, 300, 450, 600, dan 800 watt. Katalis Lempung termodifikasi CaO dikarakterisasi SEM EDX (Scanning Electron Microscopes/Energy Dispersive X-Ray) dan uji kebasaannya dengan metode Hammet. Produk biodiesel dikarakterisasi dengan Gas Chromatography-Mass Spectroscopy (GC-MS). Hasil karakterisasi menunjukkan bahwa biodiesel minyak ampas tahu telah berhasil disintesis. Biodiesel optimum dicapai pada jumlah katalis lempung termodifikasi CaO sebesar 3% dan daya microwave 600 watt dengan waktu reaksi 15 menit sebesar 90%. Terbentuknya biodiesel dibuktikan dengan beberapa puncak metil ester yaitu metil oleat (59,88%), metil palmitat (36,74%), metil stearat (2,94%), dan metil miristat (0,28%). Biodiesel has become an alternative energy source that continues to be developed. In this study, biodiesel was synthesized from tofu dregs oil using a clay modified calcium oxide (CaO) catalyst with microwave heating to produce biodiesel. Synthesis of clay modified CaO catalyst using wet impregnation method. Synthesis of biodiesel from tofu dregs oil through transesterification reaction with variations in the amount of modified clay catalyst CaO 1, 2, 3, 4, 5 % (w/w) and variations in microwave power 150, 300, 450, 600, and 800 watts. The CaO-modified clay catalyst was characterized by SEM EDX (Scanning Electron Microscopes/Energy Dispersive X-Ray) and tested for basicity using the Hammet method. The biodiesel products were characterized by Gas Chromatography-Mass Spectroscopy (GC-MS). The characterization results show that the tofu dregs oil biodiesel has been successfully synthesized. Optimum biodiesel was achieved at 3% CaO-modified clay catalyst and 600 watt microwave power with a reaction time of 15 minutes by 90%. The formation of biodiesel was evidenced by several peaks of methyl esters, namely methyl oleate (59.88%), methyl palmitate (36.74%), methyl stearate (2.94%), and methyl myristate (0.28%).

The diversity of the science of electron microscopy (EM) is difficult to compare with any other instrument-supported science. Not only the multitude of methods but also the variety of electron beam instruments preclude a clear definition of the boundary of electron microscopy fields of application and most likely it will touch and influence other branches of science which are at first glance, unrelated to the subject. This thesis is devoted to developments in electron microscopy and X-ray microanalysis and their utilisation as key research tools in applied science. The work presented here has been performed on various electron beam instruments such as transmission electron microscopes (TEM), scanning electron microscopes (SEM), scanning electron microscopes with X-ray microanalytical attachments and dedicated electron probe microanalysers (EPMA). The respective methods and techniques which have been developed to satisfy the requirements of the general scientific community are also presented. This dissertation demonstrates the need for electron microscopy and outlines the advantages of using new, customer-induced methods within the campus of research institutions and beyond. Bearing in mind the multidisciplinary aspects of electron microscopy, the development and application of methods and techniques as presented in the following chapters cover a vast area of interest. It can be said that practically almost all branches of science may benefit from these in one way or another. Developments presented here are divided into the results obtained within the existing instrument configurations and the results procured after some modifications and extensions of the existing EM instrument capabilities. A new approach to the preparative techniques used to compensate for a lack of more sophisticated and expensive associated equipment spells out possibilities of achieving the same results with a minimum of financial outlay and maximum scientific gain. Some specimen modifications that were achieved by an ion etching method show how to obtain more information from a specimen which may be obscured by undesirable and difficult to remove outer layers of biological or foreign origin. In the field of X-ray microanalysis, suitability of standards is assessed by calculating a mean atomic number of standards in relation to microanalysed material. The same approach is used quantitatively to estimate a backscattered electron coefficient and an atomic number contrast in the phases of mineralogical samples. Experimental problems with trace element analysis and interferences from major elements are discussed and example of such a case is presented. The recipes are given for quantitative analysis of light elements such as oxygen, carbon and carbon-based synthetic materials (polymers). In the course of quantitative analysis of oxygen it is demonstrated that in mineralogy, stoichiometry may no longer be an ironclad guarantee. In some instances new standards, specially for quantitative work on specimens of organic origin are created, their usefulness is assessed and thoroughly examined for homogeneity. Also, it becomes evident that the well described and easily available polymers can be used as reliable standards in the light elements analysis. For the first time low magnification phenomena in EPMA have been investigated and quantified with the full benefit determined for a minimum of specimen damage and electron optics contamination. Some application programs have been written and their merits in the field of microanalysis explained and presented in full in Appendices. It is postulated that peak performance of an electron beam instrument depends on many factors, some of which, e.g. contamination may be practically beyond control of the operator. Further, some means of minimising the problems are provided. It is also shown that a very recent introduction of an environmental SEM (ESEM) is making a substantial impact on the conventional ways of specimen preparation and observation and is providing a new insight into X-ray microanalysis and related phenomena at elevated pressures (low vacuum) in a specimen chamber. The educational and aesthetic aspects of electron microscopy are considered and the ways of efficient dissemination of electron microscopy science are presented with special regard to computer-based and related technologies. Finally, certain procedures for successful assessment of a new electron beam instrument and its purchase, based on the ESEM acquisition process are recommended.

In the present study, drilling tests were carried out on Custom 450 stainless steel workpieces. The influences of control factors (cutting speed-Vc, feed rate-f and drill bit geometry-D) on the drilled holes’ surface roughness (Ra) and on the size of adhering workpiece (AW) to the drill bit was examined. The results obtained from tests designed based on the Taguchi’s L16 orthogonal array were analysed using ANOVA and grey relational analyses (GRA). Therefore, the control factors and their levels were optimised simultaneously for the quality characteristics (Ra and AW). In addition, mathematical models were also developed using Response Surface Methodology (RSM) in order to estimate the quality characteristics. The used drill bits were examined under digital and scanning electron microscopes and EDX analysis was also carried out on the drill bits. The experimental results showed that the Ra and AW increased with increasing the f. It was also seen that increasing the Vc resulted in decrease in the size of adhering layer and that the drill bit wear became clear at the highest Vc of 60 m/min. According to the ANOVA results, the most effective control factor on Ra was f with 93.11% and Vc with 58.14% on AW. GRA analysis revealed that the most influential control factor was the f and that the optimum levels were 60 m/min Vc, 0.005 m/min f and drill bit 4.

Актуальность. В наши дни особое внимание уделяется бассейнам, которые считаются потенциальными на наличие нефте- и газопроявлений. В этом отношении особый интерес проявляется к осадочным бассейнам Намкомсон и Фухань (Южно-Китайское море). В них установлены косвенные признаки глубинной дегазации по рифтовому разлому. Формирование нефти и газа тесно связано с образованием аутигенной сульфидной минерализации. Поэтому все больше вопросов возникает по поводу индикации проявлений нефтегазоностности провинций ассоциациями аутигенных минералов. В связи с этим изучение сульфидов от континентальных до океанических до сих пор является актуальной темой для исследований по всему миру. Цель: исследовать геохимические особенности пиритных образований из донных отложений осадочных бассейнов Намконсон и Фухань Южно-Китайского моря. Методы: масс-спектрометрия с индуктивно связанной плазмой; определение потерь после прокаливания и содержания SiO2 выполнено методом гравиметрии; атомно-эмиссионная спектрометрия с индуктивно связанной плазмой; оптическая и сканирующая электронная микроскопия; рентгеновская дифрактометрия; изотопная масс-спектрометрия. Результаты. Сульфидные образования из данного осадочного бассейна представляют собой агрегаты формы полой трубочки, размеры которых достигают максимум 5 см по длине и 5 мм по диаметру. Также обнаружены крупные сростки в виде ксеноморфных сгустков, сфероидальных образований. Сами агрегаты сложены преимущественно пиритом, присутствуют кварц и альбит. Пирит формирует глобулы и кристаллы формы октаэдра. В пиритных образованиях установлены высокие содержания кобальта (16,5...56,8 г/т), никеля (21,4...377 г/т) и молибдена (20,1...117 г/т). Цериевая аномалия составляет 0,90...0,93 г/т. Изотопные значения δ34S составляют от -32,9 до -47,0 ‰. Данные значения и построенные на их основе генетические диаграммы указывают на гидротермальное происхождение пиритных образований. The relevance. Nowadays, special attention is paid to basins that are considered potential for the presence of oil and gas occurrences. In this regard, the Namkomson and Fuhan sedimentary basins (South China Sea) are of interest. They established indirect signs of deep degassing along the rift fault. The formation of oil and gas is closely related to the formation of authigenic sulfide mineralization. Therefore, more and more questions arise about the indication of manifestations of oil and gas content of provinces by associations of authigenic minerals. In this regard, the study of sulfides from continental to oceanic is still a hot topic for research around the world. The aim of this work is to investigate the geochemical features of pyrite formations from bottom sediments of the Namсonson and Fuhan sedimentary basins of the South China Sea. Methods: inductively coupled plasma mass spectrometer; determination of losses after calcination and SiO2 content was performed by gravimetry; atomic emission spectrometer with inductively coupled plasma; optical and scanning electron microscopes; X-ray diffractometry; isotope mass spectrometry. Results. The sulfide formations from this sedimentary basin are hollow tube-shaped aggregates, up to a maximum of 5 cm in length and 5 mm in diameter. Large aggregates in the form of xenomorphic clots, spheroidal formations were also found. The aggregates themselves are composed mainly of pyrite, quartz and albite are also present. Pyrite forms globules and octahedral crystals. High contents of cobalt (16,5...56,8 g/t), nickel (21,4...377 g/t) and molybdenum (20,1...117 g/t) were established in pyrite formations. The Ce anomaly is 0,90...0,93. The isotopic values of δ34S range from -32,9 to -47,0 ‰. These values and the genetic diagrams derived from them indicate a hydrothermal/diagenetic origin for the pyrite formations.

Recently, additive manufacturing is of interest, and there is a trend to study additively manufactured materials such as Inconel 718 and 316L stainless steel. Additive manufacturing brings the easiness of production of complex geometries, avoids expensive tools, helps achieve interesting microstructures and obtaining promising results for future applications. Since the additive procedure is sensitive to many fabrication variables thereby affecting the microstructure and mechanical properties. This motivation promotes investigating the additively manufactured microstructure of 316L stainless steel and Inconel 718. While 316L stainless steel was fabricated using an electron-based powder bed fusion manner, directed energy deposition was preferred for Inconel 718. Samples were examined utilizing optical and scanning electron microscopes. Results suggest processing of 316L stainless steel gives rise to the same porosity rate as Inconel 718. Bimodal equiaxed austenite grain morphology was observed whereas no dendrite presence was detected for 316L stainless steel. Additive manufacturing types do not cause a significant change in the level of porosity for Inconel 718 alloy. Unlike the case of stainless steel, additive manufacturing results in dendritic microstructure formation in Inconel 718 whereas powder bed fusion-type production triggers a better refinement compared to that of directed energy deposition.

Functions of mucin, as the major macromolecular component in saliva or gastric fluids, are drawing increasing attention in the context of understanding the oral processing or digestion of dairy foods at the molecular level. This study was designed to investigate the interactions between β-lactoglobulin (BLG)-lactose, mucin-lactose and BLG-lactose-mucin at the molecular level under different temperature and pH conditions using fluorescence spectroscopy in combination with scanning electron microscopes (sem). It is the first study of its kind. There was no lactose-dependent quenching on BLG fluorophore in the range of 0–10 mM lactose concentration. On the contrary, there was a continuous increase in the fluorescence intensity of the BLG protein when the lactose concentration increased, especially at 25°C. BLG-lactose complex became thermally unstable at 37 and 45°C. Moreover, BLG exhibited a pH dependent conformational change and had higher fluorescence intensity at pH 3 than pH 6.8. The fluorescence result was in correspondence with sem images where we observed lactose crystals gathering around and on the BLG molecule, but lactose molecules could not be seen in the presence of mucin. It was anticipated that mucin molecules interacted with BLG-lactose complex via electrostatic attraction and formed an extra protective layer around the BLG molecules to avoid solvent exposure.

To make use of industrial solid waste from paper mills, namely paper mill sludge (PMS), and to develop green construction materials, the samples were tested by using these methods that include unconfined compressive strength tests, dry density tests, water absorption tests, scanning electron microscopes (SEM), and X-ray diffractometers (XRD). The effects of different dosages, different particle sizes, and different initial water contents of PMS on the strength and microscopic properties of magnesium oxychloride cement were studied. Results show that the compressive strength of the samples decrease with the increasing of particle size and initial water content, and it first increases before decreasing when PMS content increases. PMS can lessen water absorption while having little impact on the dry density. The compressive strength, which can reach 58.47 MPa, is at its highest when the mixing percentage of PMS is 60%. At this point, the composite material's Phase 5 crystal is longer and the water absorption rate is only 6.8%. The obtained conclusions can provide a reference for the engineering application of paper mill sludge-magnesium oxychloride cement composites. Keywords: Magnesium oxychloride cement, Paper mill sludge, Composite materials, Mechanical properties, Microscopic mechanism, Cemento de oxicloruro de magnesio, Lodos de papelera, Materiales compuestos, Propiedades mecánicas, Mecanismo microscópico.

Background and objective: Agricultural plastic waste (APW), which includes various types of plastics and greenhouse film, accounts for the largest volume of annual average incineration of plastic (Korea Environment Corporation, 2021). Open-burning incineration of such APW emits metallic particulate pollutants, the human hazard of which is widely known. As such, the systematic management of incinerable APW is required. Furthermore, basic physicochemical research on particulate pollutants (PPs) is needed for related policy decision-making.Methods: The U.S. EPA particulate test method (Method 5G) was applied to set up the experimental infrastructure for an open-air incineration simulation. Scanning electron microscopes with SEM-EDS and XRF were used for a chemical species analysis of the generated particulate matter (PM). Low-density polyethylene (LDPE), used as a greenhouse material and collected by the Dangjin plastic collection office of the Korea Environment Corporation, was used as samples and subjected to incineration test three times.Results: Chemical speciation by an XRF analysis showed that the major chemical components of LDPE before incineration, listed in order of their content, were Fe (26.87%, SD = 20.67) > Si (25.91%, SD = 11.29) > Al (16.43%, SD = 7.23), which was changed to Si (44.51%, SD = 0.25) > Zn (16.53%, SD = 0.03) > Ba (15.73%, SD = 0.05) after incineration. An SEM-EDS analysis found the PM emitted as rock-like shapes and cotton-like shapes. Regarding the weight ratio, the rock-shaped particles contained less C (8.94 wt%, SD = 1.90) and more Al (11.77 wt%, SD = 3.08) and Fe (9.58 wt%, SD = 7.14), whereas the cotton-shaped particles contained more C (29.44 wt%, SD = 3.97), less Al (2.34 wt%, SD = 0.19), and an untraceable amount of Fe (ND).Conclusion: This study found that PPs emitted through the incineration of APW such as LDPE can be classified into rock-like shapes and cotton-like shapes, which is related to the difference in weight ratio of non-metals (C), transition metals (Fe), and other metals (Al) in unit particulate matter.

This research reports on the microstructural characterization and nanomechanical evaluation of hybrid aluminium-based composite, fabricated by reinforcing pure aluminium matrix with zirconia (ZrO2) and ferrotitanium (TiFe) particles. The composites were consolidated using the spark plasma sintering technique, and the properties of the reinforced composites were examined and compared with pure aluminium samples fabricated using the same sintering parameters. The formation of new phases in the hybrid composites was ascertained using the X-ray diffraction technique, while the morphologies of the starting powders and as-sintered specimens were analysed using optical and scanning electron microscopes. Mechanical tests such as Vickers microhardness and frictional coefficient were determined to ascertain the respective strength and tribological performance. Nanoindentation test was also carried out to evaluate the nanomechanical properties such as penetration depth, elastic modulus, work indentation, and indentation creep. The results from this study revealed that mixing and sintering the admixed powders at sufficiently high temperature resulted in the formation of new phases which contributed to improved mechanical performance of the hybrid composites. The absence of pinning effect in loading and unloading curves from the nanoindentation test conducted confirmed the homogeneous dispersion of the reinforcement particles. Overall, the sample reinforced with 5% TiFe and 5% ZrO2 exhibited the most improved mechanical properties, while the unreinforced aluminium sample recorded the least mechanical and nanomechanical performance.

Correlative microscopy approaches are attracting considerable interest in several research fields such as materials and battery research. Recent developments regarding X-ray computer tomography have made this technique available in a compact module for scanning electron microscopes (SEMs). Nano-computed tomography (nanoCT) allows morphological analysis of samples in a nondestructive way and to generate 2D and 3D overviews. However, morphological analysis alone is not sufficient for advanced studies, and to draw conclusions beyond morphology, chemical analysis is needed. While conventional SEM-based chemical analysis techniques such as energy-dispersive X-ray spectroscopy (EDS) are adequate in many cases, they are not well suited for the analysis of trace elements and low-Z elements such as hydrogen or lithium. Furthermore, the large information depth in typical SEM-EDS imaging conditions limits the lateral resolution to micrometer length scales. In contrast, secondary ion mass spectrometry (SIMS) can perform elemental mapping with good surface sensitivity, nanoscale lateral resolution, and the possibility to analyze even low-Z elements and isotopes. In this study, we demonstrate the feasibility and compatibility of a novel FIB-SEM-based correlative nanoCT-SIMS imaging approach to correlate morphological and chemical data of the exact same sample volume, using a cathode material of a commercial lithium battery as an example.

To investigate the reduction behaviour of different reductants such as charcoal (CC), thermal coal (TC), and carbon black (CB) with HIsarna slag, a series of isothermal reduction experiments were performed in a vertical tube resistance furnace (VTF), coupled with a Quadrupole mass spectrometer (QMS) at 1450 °C, 1475 °C and 1500 °C. The results confirm that the highest overall reduction rate was achieved by CC, followed by TC and CB. The reduction mechanism between FeO containing molten slag and the selected carbonaceous materials is determined by studying the morphology of the water quenched samples at the intervals of 1.5, 3 and 5 minutes, using optical and scanning electron microscopes. The results reveal that the overall reaction is controlled by two main mechanisms: (1) nucleation and growth of CO bubbles, proceeded by the gaseous intermediates CO and CO2; and (2) diffusion of FeO in the molten slag. The initial reduction period in which chemical reaction control is dominant, can be described by the Avrami–Erofeev model, whereas the final period is described by the three-dimensional diffusion model.

Pollen morphology of species from the subgenera Limniris (Tausch) Spach and Scorpiris Spach of the genus Iris L. (Iridaceae) of the flora of Armenia was studied using light and scanning electron microscopes. The results revealed that the main differences between these two subgenera are the shape of pollen grains and the type of pollen apertures. Boat-shaped pollen grains with an monosulcate apertures were found in representatives of the subgenus Limniris, while species of the subgenus Scorpiris are characterized by the spheroidal inaperturate pollen grains.

The paper provides a novel technique for merging graphene nanoplatelets (GNPs) within aluminium matrix (AA 6061) by continuous drive friction welding (CDFW). The welding processes were done at 1400 rpm and 2000 rpm rotational speeds with two different frictional loads 2000 N and 2500 N for 5 sec and 7 sec welding times. The welded joints were subjected to tensile and hardness tests. The heating-cooling cycles through the welding process were monitored. The microstructure investigation was performed using optical and scanning electron microscopes (SEM). The effect of welding conditions on the ultimate tensile strength (UTS) results of AA 6061 and AA 6061/GNPs were completely studied in details. There is no big detectable variation in the mean hardness values due to the GNPs addition. The best welding conditions for achieving the highest mechanical properties were defined. The presence of GNPs in the welded joints results in lower heating at the welded joint at the same welding conditions. Finer grain structure and homogeneous distribution for the GNPs within the welding zone were observed.

Existing techniques for examining the everted vesica (endophallus) of Lepidoptera are based primarily on cuticular preparations macerated with a caustic solution for taxonomic study. These techniques destroy muscles and other soft tissue, thus studies of the functional anatomy of the skeletomuscular apparatus of the phallus are not possible. Injection of formaldehyde solution into the phallus of fresh specimens is proposed as a new approach for studying the intact anatomy of this structure. The new technique results in simultaneously everting and fixing the vesica, resulting in a better approximation of its functional shape. This method produces properly fixed tissues and the whole structure can be processed for various further studies, including histology sectioning, scanning electron microscopy, and confocal laser scanning microscopy. The commonly used stubs for scanning electron microscopes do not allow observation of the sample from all aspects. This problem was solved by the modification of a commercially available stub. The device allows 360° rotation of the phallus, and the concept can be applied for observation of other objects as well.

Scanning electron microscopes (SEMs) are a popular analytical tool due to their high spatial resolution, large depth of field, and analytical capabilities. However, in many cases, the large-scale installation and cost of SEMs can be a barrier to entry for smaller laboratories or facilities. The introduction of a more compact benchtop SEM has changed the landscape, enabling scientists in many fields to adopt the technology and revolutionize research. Benchtop SEMs can be used in a variety of industries including materials science, pharmaceutical research, energy exploration, science education, and academia. These industries require analysis at the nanoscale for quality control, failure analysis, and R&D, for all of which the benchtop SEM is perfectly positioned to provide necessary detail. These advantages and new developments in the technology have made the benchtop SEM a widely available and well-accepted tool.

Aim and Objective: Endodontic retreatment is indicated in the event of a failure of initial treatment of the root canal and of an initial treatment that looks to be correctable with retreatment. This in-vitro study was designed to assess the efficacy of passive ultrasonic irrigation in endodontic retreatment, by employing scanning electron microscopes, on the cleanliness of dentine tubules with and without solvent in curved root channels. Material and method: Sixty human maxillary molar teeth were treated endontically. The protaper rotary instrument was used in root canals in the crown down procedure under copious 3% NaOCl (2 ml) and Glyde irrigation. The saline solution (1 ml) was used for final rinsing. The 10 sample root surfaces of each group were evaluated for SEM pictures. Results: Amongst group I and II here were more open dentinal tubules that were statistically significant (p

As part of the Hitachi High-Tech America Inspire STEM Education Outreach Programme in the UK, a successful STEM (Science, Technology, Engineering and Math) education pilot has seen over 5000 students from 80 schools given the opportunity to use scanning electron microscopes (SEMs) for their own experiments. The collaborative project allowed students to design, propose, and execute experiments to give them hands-on experience with scientific research. Feedback from the project has been resoundingly positive, with many students gaining new skills and an interest in STEM, and it looks set to grow further to allow more students access to high-level scientific equipment.

Austenitic stainless steels are mainly preferred especially for resistance to aggressive oxidizing medias and high temperature applications such as equipments and mechanical parts which are used in defense and conventional industries. In this study; 3 mm thick 304L austenitic stainless steel sheets and rings are joined to each other by using Tungsten Inert Gas welding method under pure argon shielding gas with ER316L and ER2209 filler metals. Weld metals and heat-affected zones of welded joints were examined by metallurgical and scanning electron microscopes. Microhardness, tensile and Charpy impact tests of weld regions are investigated. It has been determined that the filler metals have dominantly changed the microstructure of weld metals. The microhardness values of the welded samples joined with ER2209 filler metal was lower than the sample joined with ER316L filler metal in weld metal regions. Besides, corrosion tests indicated that the corrosion rates of welded samples joined with ER2209 filler metal is lower than the samples joined with ER316L filler metal.

In this study, the female reproductive system of Isotomus speciosus (Cerambycidae) and Mylabris cernyi (Meloidae) species were examined anatomically and histologically under light and scanning electron microscopes. The first of the adult insects was collected from Kömüşini, Kulu, Konya, and the other from Keklikdere, Bingöl, Turkey. According to the results obtained, the female reproductive system in both species consists of a pair of ovaries, lateral oviducts, a common oviduct, spermatheca, bursa copulatrix, and genital chamber. Each ovary has ~ 28 ovarioles in I. speciosus, ~ 50 ovarioles in M. cernyi. In both species, each ovariole consists of a terminal filament, germarium, vitellarium, and pedicel. However, the properties (The number of ovaries, presence-absence of terminal filament, thickness, the length of terminal filament, dimensions of germarium, the number of oocytes in vitellarium, ooplasm content of oocytes, the shape of follicle epithelium surrounding oocytes, the size of oocytes, oocyte surface differentiation) of these parts differ according to the species. In both species, previtellogenesis, vitellogenesis, and choriogenesis stages oocytes were found in the vitellarium. In this study, the similarities and differences in the anatomical and histological structures of the parts of the female reproductive system of I. speciosus and M. cernyi with species belonging to other families were compared.

Purpose The demand for titanium alloys has received massive attention in the aerospace and automotive industry owing to their magnificent electrochemically compatibility and corrosion resistance, high strength at elevated temperatures and high strength-to-weight ratio. Although titanium alloy has impressive mechanical properties, they are challenging to machine or metal form due to its poor heat conductivity, high chemical reactivity, low modulus of elasticity, high friction coefficient and difficult lubricant that limits its application field and increases wear. However, surface treatment coating with the strong metallurgical bond between the titanium alloy matrixes is novel technique to resolve these challenges. This research will illustrate the influence of laser scanning power on the microstructure and tribological behavior of Nickel (NI)-composite claddings fabricated on TC4 titanium alloy to realize the strong metallurgical bond between the titanium alloy and NI-composite coating. Design/methodology/approach In this research, TiC/TC4 alloy nanocomposites were fabricated based on different laser power and temperatures. TC4 has been selected as a base material instead of TiC for the strong metallurgical bond between the titanium alloy matrixes. Then Ni-composite coating was used as the surface treatment coating on TC4 by laser cladding (LC) technique. The Ni-based alloy coating material powder is good self-fluxing, has high-temperature resistance and is analytically pure with 200 mesh, which can easily overcome the various challenges of titanium alloy. The chemical properties of Ni composite coating include 31.2% Chromium, 8%Titenium and 3.6% Carbon. The prepared surface treatment coating characterization and microstructure behavior are analyzed using optical micrograph, X-ray diffraction, scanning electron microscopes, energy dispersive spectroscopy and electron probe micro analyzer methods. Findings It is evident that at the beginning of the experiment, if the laser power increased, the quality of the coating increased. An optimal quality of the coating is found when the laser scanning power about 12.55 kJ/cm2. Further increased laser power diminished the quality of the coating because the material plasticity had deteriorated. The TiC ceramic particle reinforced phase is dispersed into a two-phase solid solution of β-Ti and γ-Ni. The micro-hardness of the used coating is greater than the base alloy. Originality/value This research has practical value in the modern aerospace and automobile industry to increase the application of titanium alloy.

Herein, we describe a new species of turtle blood-feeding leech, Placobdella nabeulensis sp. nov. from Palearctic North Africa (Tunisia and Algeria). The new species is described based on detailed morphological analyses using light and scanning electron microscopes. Apart from the detailed morphology of the atrium, morphological features alone do not sufficiently separate the species from congeners due to the absence of distinct diagnostic characters. Therefore, we turned to molecular data to better distinguish this new species from other members of the genus and establish a basis for its genetic separation. Four DNA fragments were successfully amplified, including mitochondrial COI and 12s rDNA, as well as nuclear 28S rDNA and histone H3. We then provided the molecular descriptor of the taxon, based on redundant diagnostic nucleotide combinations in DNA sequence alignment within the Folmer region. Results of the phylogenetic analysis and species delimitation methods (ABGD, ASAP, and bPTP) based on the COI locus support the species rank of the Tunisian-Algerian Placobdella. The new species is most closely related to the European species Placobdella costata (Fr. Müller, 1846) and the present study indicates that Placobdella nabeulensis sp. nov. has likely been confused with the European counterpart in several previous studies.

In this study, the co-precipitation approach was used to make nanostructured nickel oxide (NiO) commencing with sodium hydroxide (NaOH) and nickel (II) chloride hexahydrate (NiCl2[Formula: see text]6H2O). Through the use of X-ray diffraction (XRD), scanning electron microscopes (SEM), UV-visible (UV–Vis) absorption, and Fourier transform infrared (FTIR) imaging, structural and optical studies were investigated. FTIR, photoluminescence (PL), cyclic voltammetry (CV) studies are taken. The synthesized nanoparticles were annealed at [Formula: see text]C and [Formula: see text]C. The face-centered cubic (FCC) structure of the NiO and highly crystallized nanoparticles were revealed by XRD investigations. Observation of FTIR spectra validated the composition of functional groups. Scanning electron microscopy image shows the average size is 24 nm. NiO optical band gap at [Formula: see text]C (3.37 eV) and [Formula: see text]C (2.7 eV) is revealed from UV studies. From CV graph, the sample annealing at [Formula: see text]C and [Formula: see text]C the specific capacitance was 543.6 and 519.8 F/g, respectively. This study signifies the supercapacitor application of nanosized metal oxide.

Co-precipitation, a minimal technique, was used to successfully create novel (Cr, Cu) dual-doped ZnO nanoparticles (NPs). X-ray diffraction (XRD), energy dispersion X-ray (EDX) analysis, scanning electron microscopes (SEM), and UV-visible absorption spectra had been used to characterize the produced nanoparticle. The produced NPs have a hexagonal wurtzite structure with a high phase purity, according to the XRD pattern. the substitution of Cr increased optical absorption and inducing new absorption peaks in the visible regions that correspond to the transitions from 4A2(4F) to CB and 4A2(4F) to 4T1(4F). Absorption of photon in the visible region led to increase the photo-generated electron-hole pairs and hence RO-species which responsible for photocatalytic activity. Therefore the (Cu, Cr) dual doped ZnO NPs had excellent photocatalytic activity under sun light irradiation. MTT assay was employed to analyze the in vitro cytotoxicity of Cr-doped Zn0.98Cu0.02O NPs on human normal PBMC. The toxicity is enhanced by an increase in Cr concentration in very small amounts at low concentrations and significantly at high concentrations. The antibacterial characteristics of the produced NPs was examined against the bacterial strains P. putida and B. subtilis.

A statistical optimization based on experimental work was conducted to consider ultimate tensile strength (UTS) and elongation of dissimilar joints between AA5454 and AA7075 by friction stir weld (FSW). The goal of this work is to develop a comparative study of the optimization of FSW parameters using different orthogonal arrays, i.e., L12 and L16. Four parameters correlated to softening and forging requirements (rotational speed, traverse speed, tilt angle, and plunge depth), one parameter associated with the location of base metal in the dissimilar joint, and two parameters related to an FSW tool (pin profile and Dshoulder/dpin ratio) were considered and arranged in the employed arrays. Moreover, the investigation explored the microstructure and fractography of dissimilar joints and base metals by using optical and scanning electron microscopes. The results showed that the L16OA is more accurate than L12OA for the optimization of seven parameters due to the small statistical errors. For UTS, the errors range from 0.78 to 24% for L16OA and from 27.23 to 44.14% for L12OA. For elongation, the errors run from 11 to 12.9% for L16OA and from 33.77 to 49.73% for L12OA. The accuracies of generated models range from 50 to 99.5% for L16OA and range from 30.7 to 94.9% for L12OA. Tightening the levels (narrow domain) is the main reason for switching some optimum levels between both arrays. The highest UTS obtained is 221 MPa based on the optimum levels attained from L16OA, and the highest elongation is 12.83% according to the optimum levels acquired from L12OA. Despite the deficiency of effective intermixing, the study revealed that FSW acceptably could assemble joints between AA5454 and AA7075, presenting the proficiency of FSW with welding dissimilar aluminum alloys.

The collection of archeological sites of the North Caucasus sometimes contain obsidian artefacts. The question of the sources of this type of raw material, with the use of possibilities of natural science methods for the region under study, has not been raised before. Meanwhile, for such a region as the North-Eastern Caucasus, where there are no natural outcrops of obsidian, the results of a comparative analysis of artifacts from this material will be especially clear in terms of establishing cultural contacts or migrations that took place in the past. This paper presents the results of an analysis of the elemental composition and microstructure of an obsidian piece from the Neolithic site Almalo 1 in Primorsky Dagestan and provides a comparative analysis of the data with the indicators of reference samples from an obsidian deposit in the central part of the North Caucasus. The examination, carried out using optical and scanning electron microscopes with an attachment for energy-dispersive analysis (EDA), led to the conclusion that the obsidian raw material used to make the obsidian plate from the Neolithic collection of the Almalo 1 site comes from the Zayukovo deposit in the Central Caucasus in modern Kabardino-Balkaria. This means that the direction of cultural ties of the population, which inhabited the north of the Caspian lowland of modern Dagestan in one of the segments of the Neolithic Age, was oriented towards the Central Caucasus and the Ciscaucasian steppes. The results obtained do not exclude the possibility of migrations that had a corresponding direction at the indicated time.

The core of the present work concerns the analysis of the failure mode and the fracture process induced by the flexural load in Fibre Metal Laminates (FMLs). The influence of the connection layer placed between the composite ones and the metal sheets on the fracture mode was analysed. The considered FML was made of aluminium sheets interposed with carbon fibre reinforced polymer (CFRP) layers, joined with two different types of interface: by using a structural adhesive, or by relying on the bonding capacity of the prepreg resin. Then, the mechanical performances of the produced laminates were determined through the three-point bending test procedure, and the support span was varied to investigate different loading conditions. Finally, the fracture surface morphology was analysed by using both optical and scanning electron microscopes. The type of interface was found to influence the strength of the studied FML, and different fracture modes were observed, depending on the loading condition.

The paper deals with the burials of the excavation No. 7 of the Lower-Vychegda Chezhtyyag burial ground of the Vym culture of the Vychegda Perm, in which objects indicating the occupation of the population by bronze casting were found. The analytical studies were based on using optical and scanning electron microscopes. Based on the analysis of the grave goods, the belonging of these burials to women is substantiated. The conducted geochemical analysis of scrap metal found in the burials is represented by tin bronzes with lead separations, metallurgical copper, tin and silver-copper alloy. Metallurgical copper, lead-copper, zinc bronze, and tin bronze were used to manufacture adornments and household items. Convincing evidence of local bronze casting was obtained. Tin bronzes, lead and copper were produced mainly locally. Among the non-ferrous metal products, both products of local craftsmen and imported ones are presented. The similarity of the composition of non-ferrous metal and scrap metal products confirms the assumption that the burials in question belong to female casters, whose main field of activity was bronze casting.

International audience; The development of instruments combining multiple characterization and imaging tools drove huge advances in material science, engineering, biology, and other related fields. Notably, the coupling of SEM with microRaman spectrometry (mu Raman) provides the means for the correlation between structural and physicochemical properties at the surface, while dual focused ion beam (FIB)-scanning electron microscopes (SEMs) operating under cryogenic conditions (cryo-FIB-SEM) allow for the analysis of the ultrastructure of materials in situ and in their native environment. In cryo-FIB-SEM, rapid and efficient methods for assessing vitrification conditions in situ are required for the accurate investigation of the original structure of hydrated samples. This work reports for the first time the use of a cryo-FIB-SEM-mu Raman instrument to efficiently assess the accuracy of cryo-fixation methods. Analyses were performed on plunge-freezed highly hydrated calcium phosphate cement (CPC) and a gelatin composite. By making a trench of a defined thickness with FIB, mu Raman analyses were carried out at a specific depth within the frozen material. Results show that the mu Raman signal is sensitive to the changes in the molecular structures of the aqueous phase and can be used to examine the depth of vitreous ice in frozen samples. The method presented in this work provides a reliable way to avoid imaging artifacts in cryo-FIB-SEM that are related to cryo-fixation and therefore constitutes great interest in the study of vitreous materials exhibiting high water content, regardless of the sample preparation method (i.e., by HPF, plunge freezing, and so on).

Zinc oxide nanoparticles (ZnO-NPs) are known for their antioxidant effects. In this study, ZnO-NPs were synthesized using aqueous extract of Maclura pomifera fruit; then, their effects on the quality of ram cauda epididymal spermatozoa were evaluated during storage at 4°C. ZnO-NPs formation was characterized by ultraviolet-visible spectroscopy (UV-vis), energy dispersive spectroscopy (EDX), field emission scanning electron microscopes (FE-SEM) and Fourier transform infrared (FTIR) spectroscopy. Cytotoxicity responses were investigated by 3-[4,5-dimethylthiazole-2-yl]-2,5-diphenyltetrazolium bromide (MTT). Cauda epididymal spermatozoa were obtained from testicles collected from abattoir(s). The sperm samples were pooled. The samples were diluted by extender and supplemented with different concentrations of ZnO-NPs (0, 1, 5 and 25 µg/ml) and cooled to 4°C for 72 hr. Total motility, viability, DNA and membrane integrity, morphological abnormality, malondialdehyde (MDA) and antioxidant activities: superoxide dismutase (SOD) and total antioxidant capacity (TAC) of cooled diluted samples were evaluated. Addition of 1 μg/ml of ZnO-NPs increased sperm viability under normal conditions (p .05). Extender supplementation with 1 μg/ml of ZnO-NPs improved sperm total motility, viability, DNA and membrane integrity during storage periods (p .05). Moreover, using 1 μg/ml of ZnO-NPs improved (p .05) MDA, TAC and SOD activities after 72 hr compared to other treatments. In conclusion, there were some beneficial effects of ZnO-NPs supplementation in ram epididymal sperm extender during oxidative stress conditions and cooled storage.

Research subject. Detailed mineralogical and geochemical studies of rocks of the Tukan gold-quartz deposit (quartz veins, dolerites, gabbro-diorites) were carried out. The deposit is one of numerous small gold-quartz occurrences in the Khudolaz trough of the West Magnitogorsk zone.Methods. The morphology and composition of native gold was studied using an Axios kop 40 A optical microscope and Tescan Vega 3 and JEOL-6390LV scanning electron microscopes. The chemical composition of rocks was determined by X-ray fluorescence (Carl Zeiss VRA-30) and atomic emission (Shimadzu ICPE-9000) analyzes. Fluid inclusions were analyzed using Linkam TMS-600 thermostage equipped with Link-System 32 DV-NC software and an Olympus BX51 optical microscope. The gas composition of fluid inclusions was examined by Raman spectroscopy (Horiba LabRam HR800 Evolution).Results. Gold-bearing quartz veins and dolerites intersect ing the gabbrodiorite intrusion of the Khudolaz complex are associated with submeridional strike-slip faults. Native gold has a various morphology and is confined to cracks in quartz veins and altered dolerites. The composition of gold is stable, with the average fineness of 871 ± 8.3‰. An analysis of fluid inclusions in a gold-bearing quartz vein showed that gold was formed at temperatures of no less than 186–230°С from a fluid with a salinity of 4–8 wt % NaCl-eq. The presence of gases СО2, N2 and CH4 was found in fluid inclusions. Dolerites and gabbrodiorites hosting gold-bearing veins contain sulfides (pyrite, pyrrhotite, chalcopyrite, pentlandite, violarite), sulfoarsenides (cobaltite and its analogs), as well as mine rals of Ag (hessite) and Pb (kuranakhite and phases similar in composition to minerals of the dugganite group and burckhardtite). Conclusions. The sustained composition of native gold and a narrow range of salinity and homogenization temperatures of fluid inclusions indicate the formation of gold during a single stage of mineralization. The main source of gold could have been the dolerite dikes of the Ulugurtau complex. The presence of CO2, N2 and CH4 gases in fluid inclusions from goldbearing quartz indicates that not only magmatic fluid, but also fluid from the host rocks took part in mineral formation. The low value of the ratio X(CO2)/X(CH4) ≤ 0.7 indicates a moderately reduced ore-forming fluid. Low Au concentrations (0.1– 0.4 ppm) in quartz veins, dolerites, and gabbro-diorites, including those containing visible gold, indicate a weak commercial potential of the deposit

The clinical significance of vancomycin-intermediate S. aureus (VISA) infections is intensified by its tendency to develop resistance to antimicrobials and persistent infections. The decreasing effectiveness of the antimicrobials available is now seriously compromised; thus, there is an emergent need to invent new classes of antimicrobial agents that can rapidly and efficiently eradicate infections. Fe3O4@SiO2@chitosan (CS) nanocomposites were successfully synthesized and then decorated with nisin to gain Fe3O4/SiO2/CS/nisin-based magnetic nanostructures (Fe3O4@SiO2@CS-NISIN). The nanomaterials were characterized comparatively via FTIR (Fourier transform infrared spectroscopy), XRD (X-ray diffraction), FE-SEM (field emission scanning electron microscopes), DLS (dynamic light scattering), and VSM (vibrating sample magnetometer) methods. The methyl thiazol tetrazolium (MTT) assay was performed to determine the inhibitory effects of antibacterial agents on the cell viability. The in vitro bactericidal effect of all compounds was characterized using the microdilution assay. Finally, the topical antibacterial efficacy of free nisin, Fe3O4@SiO2@CS, and Fe3O4@SiO2@CS-NISIN nanocomposites against murine superficial wound infection models was determined. The functionalized nanocomposites were more efficient in suppressing bacterial growth in vitro and in vivo compared to the same quantities of untargeted nanocomposites. MTT results showed acceptable biocompatibility of all nanoformulations, and no substantial difference in the cell viability was recorded between treated cells and untreated control. These results suggest that Fe3O4@SiO2@CS-NISIN nanocomposites can be served as an alternative antimicrobial agent in innovative and emerging technologies to treat a variety of staphylococcal infections.

Background. Comparative palynomorphological studies of naturally occurring and introduced Pterocarya Kunth representatives reveal the taxonomic significance of pollen morphological features and pollen characters of cultivated plants. The quality of pollen material and the potential of the plants from the Botanical Garden of BIN RAS for introduction are characterized.Materials and methods.Pollen grains were investigated using light, confocal laser scanning and scanning electron microscopes. Fertility was assessed using the standard acetocarmine method.Results.Comparison of pollen morphology in cultivated and naturally growing plants of this genus was made for the first time. Pollen fertility of two cultivated species (Pterocarya rhoifolia Siebold et Zucc., and P. stenoptera DC.) was very high, generally over 90%. Fertility of P. fraxinifolia (Lam.) Spach grains varied from 28 to 73% in different years, which is a low or medium level of pollen quality. Morphologically, pollen grains of all 12 specimens from five taxa are flattened, medium sized, 21–45 μm in diameter, with 4–8 pores; pores are located mainly at or near the equator. The pores are round or oval, with a limbus. Exine is three-layered, thickened near the pore. The sculpture is microechinate. The low-fertile P. fraxinifolia specimen contains small pollen grains, as well as grains in tetrads and dyads. The data on the introduction of the genus in St. Petersburg are presented.Conclusion.The palynonomophological description is diagnostic for the genus Pterocarya. The Pterocarya pollen is well distinguishable from other wind-pollinated taxa; however, species identification by pollen for spore-pollen analysis is not practicable. Morphologically, the most diverse are the grains of the low fertile specimen P. fraxinifolia. The limited possibility of seed propagation of P. fraxinifolia is probably explained by low pollen fertility. The pollen quality of the introduced P. rhoifolia and P. stenoptera is high.

Aphis gossypii Glover is one of the most important pests in cotton seedling. The specialized mouthpart and short generation time allow them seriously restricted the quality and yield of cotton. With the electrical penetration graph (EPG), optical microscope, and scanning electron microscope, the physical characteristics of trichomes on the cotton leaf surface and their effects on the feeding behaviors of cotton aphids were investigated in this study. Two types of leaf trichomes, glandular trichomes, and asteroid non-glandular trichomes were observed on the surface of cotton leaves under optical and scanning electron microscopes. As a whole, EPG results mainly showed differences in a non-probe waveform which meant searching on the leaf surface, and a potential drop waveform which meant intracellular penetration. Whereas pathway waveform, xylem waveform, and phloem waveform showed inconspicuous differences. Detailed indicators were slightly different at different periods. Our results confirmed that the structure of trichomes may directly affect the searching behaviors of herbivorous insect pests and hence regulate the plant-environment interactions.

Mg-based biomaterials are commonly used as biodegradable orthopedic implants (e.g., bone regeneration applications). However, achieving high biocompatibility and corrosion resistance has remained a challenge to be tackled. In this work, to investigate various fabricated coatings (with and without pre- anodizing), five categories of samples are considered: (a) bare Mg alloy (Mg), (b) Anodized Mg alloy (Mg-A), (c) CS-coated Mg alloy (Mg-C), (d) CS-coated anodized Mg alloy (Mg-AC), and (e) CS-CNT-coated anodized Mg alloy (Mg-ACC). These samples were characterized by using Field Emission Scanning Electron Microscopes (FE-SEM), Energy Dispersive Spectroscopy (EDS), Fourier Transform Infrared Spectroscopy (FT-IR), and Raman Spectroscopy. The adhesion within the coated samples was compared. Then, the effects of the coatings were evaluated by comparing wettability, corrosion behavior, and biocompatibility for bare and coated samples. The adhesion test showed that the coatings exhibited higher adhesion for Mg-AC and Mg-ACC compared to Mg-C. Desired wettability was achieved as the contact angles of coated samples were in the range of 55°– 65°. Electrochemical impedance and polarization as well as immersion tests showed higher corrosion resistance for coated samples. The composite coated sample showed improved cell adhesion since the osteoblast cells covered almost the entire surface of the sample. Moreover, osteoblast cell viability for the sample was around 40% higher than that of the bare sample. Graphical abstract

Purpose This study aims to offer an effective nanocomposite for potential use to consolidate and protect deteriorated archaeological pottery. Design/methodology/approach Three nanocomposites were used in the experimental study. This study used nano Primal AC33, silicon dioxide (SiO2) and montmorillonite (MMT) nanoparticles to protect and consolidate pottery specimens. Pottery specimens were made at 800°C for this investigation. Consolidation materials were applied with a brush. The properties of the treated pottery specimens were assessed using several methods such as digital and scanning electron microscopes, static water contact angle, color alteration, physical properties and compressive strength. Findings Microscopic examination indicated the ability of the nano Primal AC33/MMT nanocomposites to cover the outer surface well and bind the inner granules. Concerning specimens with code F treated with nano Primal AC33 5%/MMT 3% nanocomposites, it achieved an increase in contact angle (120°), density (1.23 g/cm3) and compressive strength (561 kg/cm2), as well as a decrease in color change (ΔE = 2.62), water absorption (4.45%) and porosity (5.46%). The novelty of the results is due to the characteristics of nano Primal AC33 5%/MMT 3% nanocomposites used in the current study. Originality/value This study describes the significant results of the analytical methods used for evaluating consolidation materials used in this study. The findings offer useful information for the protection of archaeological pottery. The investigation indicated that nano Primal AC33 5%/MMT 3% nanocomposites gave the best results. Therefore, it is recommended to use this nanocomposite to consolidate archaeological pottery. As a result, the current work provides a promising first step in conserving archaeological pottery for future studies.

State-of-the-art electron microscopes such as scanning electron microscopes (SEM), scanning transmission electron microscopes (STEM) and transmission electron microscopes (TEM) have become increasingly sophisticated. However, the quality of experimental images is often hampered by stochastic and deterministic distortions arising from the instrument or its environment. These distortions can arise during any stage of the imaging process, including image acquisition, transmission, or visualization. In this paper, we will discuss the main sources of distortion in TEM and S(T)EM images, develop models to describe them and propose a method to correct these distortions using a convolutional neural network. We demonstrate the effectiveness of our approach on a variety of experimental images and show that it can significantly improve the signal-to-noise ratio resulting in an increase in the amount of quantitative structural information that can be extracted from the image. Overall, our findings provide a powerful framework for improving the quality of electron microscopy images and advancing the field of structural analysis and quantification in materials science and biology.

В статье приведены результаты микрозондового анализа сильномагнитных фаз почв и мхов-эпифитов промышленного города Лысьва Пермского края. В качестве объектов исследования были выбраны почвы и эпифитный мох плевроциум шребера (Pleurozium schreberi (Willd. ex Brid.) Mitt.) на стволах тополя черного (Populus nigra L.). В данной работе отражены исследования элементного химического и минералогического составов частиц магнитной фазы почвенных и эпифит -ных образцов. Изученные образцы характеризуются наличием в своем составе магнитных частиц, обогащенных Zn, Pb, Ni, Cu, Cr. Валовой химический состав почв определен на спектрометре Axious Advanced PW 4400/04. Анализ магнитных частиц образцов выполнен с использованием растровых электронных микроскопов: VEGA II LMU, FEI Quanta 650 FEG. Частицы магнитных фаз имеют обломочную и сферическую формы. По результатам исследования выдвинуто предположение, что сферические магнитные частицы аккумулируются в верхних горизонтах почв и в составе мхов-эпифитов в результате их аэрального загрязнения ввиду деятельности промышленных предприятий города Лысьва. Приоритетным загрязнителем почв является Zn, что связано с техно-геохимической специализацией промышленных предприятий города Лысьва., The article presents the results of microprobe analysis of highly magnetic phases of soils and epiphytic mosses in the industrial city of Lysva, Perm region. Soils and epiphytic moss Pleurozium schreberi (Willd. ex Brid.) Mitt. on the trunks of black poplar (Populus nigra L.) were chosen as the objects of study. This paper reflects the study of the elemental chemical and mineralogical compositions of the particles of the magnetic phase of soil and epiphytic samples. The studied samples are characterized by the presence in their composition of magnetic particles enriched in Zn, Pb, Ni, Cu, Cr. The bulk chemical composition of soils was determined on an Axious Advanced PW 4400/04 spectrometer. Analysis of the magnetic particles of the samples was performed using scanning electron microscopes: VEGA II LMU, FEI Quanta 650 FEG. The particles of the magnetic phases have detrital and spherical shapes. Based on the results of the study, it was suggested that spherical magnetic particles accumulate in the upper horizons of soils and in the composition of epiphytic mosses as a result of their aerial pollution due to the activity of industrial enterprises in the city of Lysva. The priority soil pollutant is Zn, which is associated with the techno-geochemical specialization of industrial enterprises in the city of Lysva.

Wadi Aidib lies at the extreme southern part of the Eastern Desert, Egypt, between 22o15'- 22o21' N and Longitudes 36o20'-36o30' E. Landsat ETM+ false color composite image (bands 3, 2, 1) was used for regional discrimination for different rock types and provide an excellent base map for the study area, morphological features of the stream deposits of the study area were known from Landsat ETM images, in addition to several field observations. The studied stream sediments accumulate in the form of alluvial fans. They are mainly composed of sands, gravels, boulders and contain some heavy valuable minerals which are derived from metavolcanics, metasediments, quartz diorite, biotite and alkali feldspar granites. Heavy liquid separation and magnetic separation techniques in addition to microscopic examination for the studied stream sediment samples were applied to identify the heavy minerals in these sediments. These minerals are represented by magnetite, ilmenite, rutile, garnet, zircon, monazite and Green silicates. The distribution of some elements in the study area is clear that they are concentrated near the outcrops of granites. The radionuclide concentrations were measured in different stations using a calibrated gamma-ray portable detector (RS 230) and the heavy minerals causing radioactivity were separated by heavy liquids and determined by binuclear and environmental scanning electron microscopes. Uranium ranges between 5.25 and 32.05 ppm with an average of 16.63 ppm, Th between 4.4 and 17 ppm with 11.34 ppm as an average and potassium fall between 1.8 and 5.15% with an average of 3.4 %. Correlation between soil radioactivity and its mineralogical content indicate that the high radionuclides contents are mainly attributed to the presence monazite which is the principal source of both uranium and thorium. Uranium high concentrations could be related to the metamict zircon. Absorbed Dose Rate (D), annual effective dose equivalent radium equivalent activity, external and internal hazard index, in addition to activity gamma index caused by gamma emitting natural radionuclide are determined from the obtained values of 238U, 232Th and 40K. Fairly, some of the studied stations do not satisfy the universal standards. 40K plays the main and most important role in dose rate contribution.

Biofilms act as physical barriers to the immune system and drugs used by the host, resulting in antimicrobial resistance. Biofilms reduce the chances of eradicating infections and can result in relapses and backsliding after conventional treatment. Biofilms have a big impact on food safety in the food industry; many foodborne outbreaks have been linked to pathogenic bacteria that can form a biofilm. Biofilm-associated infections can cause not only severe symptoms but also serious side effects and even death. The findings of an experimental study of pathogenic bacteria like Pseudomonas aeruginosa, Salmonella enteritidis, and Staphylococcus aureus forming biofilms are presented in this article. The process of biofilm formation and its development phases were displayed with preserved architectonics using light and scanning electron microscopes. The amount of biofilm formed was influenced by the growth medium as well as the incubation conditions and time. Biofilm-forming microbes are a common cause of complicated and recurrent diseases, and they're usually linked to MDR bacteria, which account for nearly 80% of all refractory nosocomial infections. Medical device- and tissue-associated biofilm infections are two types of biofilm infections. Understanding the pathogenesis and factors that contribute to biofilm formation, as well as the disruption and dispersal mechanisms of biofilms, will aid in the development of improved anti-biofilm strategies. Overall, this literature review can serve as a single source of information about microbial biofilm formation and mitigation strategies, which could be extremely useful to biofilm researchers. Keywords: biofilm; pathogenic bacteria; infection; anti-biofilm.

The simulation program “SEM Nano” is introduced to explain and visualize probe formation in field-emission scanning electron microscopes (SEMs). The program offers an easy and intuitive graphical user interface (GUI) to provide input in terms of understandable SEM parameters and visualization of the output. The simulations are based on wave optics treatment of the electron beam in the SEM column. Based on input parameters provided by the user, the spatial intensity distribution of electrons is calculated at the specimen by incorporating the effects of diffraction, aberrations, coherence, and noise. Given the specimen structure signal (So), the program has the capability to produce an image of the specimen using the electron probe intensity distribution. Finally, a feature is provided to reconstruct the electron probe intensity from the noisy image using a Wiener filter-based deconvolution.

Low-voltage scanning electron microscopes (LV-SEMs) are widely used in nanoscience. However, image resolution for SEMs is restricted by chromatic aberration due to energy spread of the electron beam at low acceleration voltage. This study introduces a new monochromator (MC) with offset cylindrical lenses (CLs) as one solution for LV-SEMs. The MC optics, with highly excited CLs in offset layouts, has advantageous high performance and simple experimental setup, making it suitable for field emission LV-SEMs. In a preliminary evaluation, our MC reduced the energy spread from 770 to 67 meV. The MC was integrated into a commercial SEM equipped with an out-lens (a conventional objective lens without immersion magnetic or retarding electric fields) and an Everhart–Thornley detector. Comparing SEM images under two conditions with the MC turned on or off, the spatial resolution was improved by 58% at 0.5 and 1 keV. The filtering effect of the MC decreased the probe current with a ratio (i.e., transmittance) of 5.7%, which was consistent with estimations based on measured energy spreads. To the best of our knowledge, this is the first report on an effective MC with higher-energy resolution than 100 meV and the results offer encouraging prospects for LV-SEM technology.

The micromorphology and anatomy of the epidermis of the abaxial surface of the leaf of Populus tremula L. (sect. Populus) and P. nigra L. (sect. Aigeiros Duby, Salicaceae) using light and scanning electron microscopes. The main cells of the epidermis of P. nigra according to N.A. Aneli are curvilinear curvilinear; the coefficient of tortuosity of the anticline walls is 14.3±0.3 µm/mm2; the area is from 437.5 to 1300.0 mm2 (average 820.9±39.9); P. tremula – sinuous, close to indented; 23.2± 0.4 µm/mm2; from 187.5 to 612.5 mm2 (average 351.7±12.6). The closing cells of the stomata in both species are lentil-shaped, multidirectional, located on the same level with the main ones. In P. tremula they are rather small (their length is 17.9± 0.4 microns), and in P. nigra they are larger (24.6± 0.4 microns). Stomata density in P. tremula ranged from 333 to 571 pcs/mm2, in P. nigra – from 100 to 183 pcs/ mm2. There is a folded (striate) microrelief near the stomata. In P. nigra, straight or sinuous folds ranging from 5 to 25 pieces diverge in different directions at a distance of 10 to 27 microns. Three types of microrelief were found. At P. tremula a small number of periosteal folds (from 3 to 17 pcs.) diverged perpendicular to the stomatal slit in different directions at a distance of ~ 10-20 microns.

This study investigated the microstructure, hardness, tensile and tribological behaviour of a cooling slope Al–Si–Mg alloy following ECAP and T6 heat treatment. The optical and scanning electron microscopes were applied to investigate the microstructure of the as-cast material and heat-treated ECAPed Al–Si–Mg alloy. The dry sliding wear test was tested with three different loads of 10 N, 50 N, and 100 N with constant sliding speed and sliding distance at 1.0 m/s and 9000 m, respectively, using the pin-on-disc tribometer. The hardness and tensile properties were evaluated through microhardness, UTS, and YS measurement for the as-cast Al–Si–Mg alloy, both heat-treated with and without ECAPed alloys. Moreover, wear rate and COF in the Al–Si–Mg alloy with different loads were analysed and linked with microstructural and strength behaviour after the ECAP process. Meanwhile, these analyses of results were correlated with the behaviour of the as-cast Al–Si–Mg aluminium alloy and heat-treated non-ECAPed alloy. Results demonstrated that a combination of ECAP processing and T6 heat treatment improves the mechanical behaviour, while the COF and wear rate are improved at a load of 100 N.

Since various kind of receptors in insects are mainly located on their legs. We estimate the influence of ultraviolet-C on the leg morphology and trichoid sensilla of Tribolium castaneum (Herbst, 1797) (Coleoptera: Tenebrionidae), zero-day-old pupae were irradiated with UV-C at a distance of 35 cm for 1, 2, 4, 8, 16, 32, and 64 min. Changes in leg morphologies and trichoid sensilla were determined using light and scanning electron microscopes. UV-C radiation caused the abnormalities of an adult’s legs that were classified into three levels; mild, moderate, and strong. Legs of the resulting adults were developed into malformed structures that lacked clear segmental identity. The severity of leg abnormalities was recorded in a dose-dependent manner. UV-C significantly decreased the length and width of the femur, tibia, and tarsus. In the strongly affected level, the femur was reduced in size while the tibia and tarsus were completely deleted, and there was no evidence of claws. Scanning electron microscopy showed the wrinkled cuticle on the leg segment, and the sensilla of the resulting adults appeared less in number. After UV-C radiation, the trichoid sensilla on the femur became longer and wider, but the trichoid sensilla on the tibia were shorter and narrower. Taken together, UV-C irradiation during pupal stage interfered development of legs and brought about specific malformation features.

Verbascum × aytachii nothosp. nov. H. Duman & Uzunh. (sect. Bothrospermae) is described and illustrated as a new natural hybrid from the Orhaneli (Bursa Region) area in Western Anatolia, Turkey. This species is identified to have some intermediate morphological and palynological characteristics that place it between the parents which are V. ekicii and V. basivelatum. A comprehensive description, ecology, a distribution map and a detailed illustration are provided. Furthermore, pollen morphological properties of V. × aytachii and its parents are compared via light (LM) and scanning electron microscopes (SEM).

Ceramic microspheres have attracted significant attention, while the preparation of hierarchically porous ceramic microspheres with high porosity, good sphericity, and controllable size or shape in a short time remains a challenge. Herein, we developed a highly adaptable methodology for the preparation hierarchically porous ceramic microspheres with high porosity and favorable shape in a short time. The UV-curing assisted molding method combined with the Pickering emulsion method was utilized to prepare hierarchically porous ceramic microspheres. Under the irradiation of a UV-curing lamp (395 nm, 50 W), the Pickering emulsion can be cured within as short as 10 s. The microstructures of the three microspheres with different shapes were characterized by scanning electron microscopes (SEM). The as-prepared microspheres had a high sphericity, the interconnectivity of pores was as high as 54 %, and its porosity was as high as 73.4 % ± 3.0 %, while the density was quite low at ∼ 1.02 g/cm3.

The paper is focused on the developing a predictive mathematical model for describing thermodynamic processes connected with the moist air depressurization in vacuum chambers. Equations of the mathematical description are based on principles of the energy and mass conservation, which are complemented by the moist air thermodynamics, the state behavior of water and vapor, including principles of the critical flow. The described problem has been solved using the MATLAB software. In the paper, two cases are applied and discussed: the vacuum drying and the specimen chamber of an environmental scanning electron microscope. The specific requirements are especially important for environmental scanning electron microscopes, where it is possible to observe samples, which contain water, in their natural condition. If the air pressure, temperature and humidity do not have suitable values, observed sample may be dried or damaged.

Cement has been well documented to positively affect the early-age strength of the cement asphalt emulsion mixtures (termed as CAEM) without compromising workability. However, the long-term performance of the CAEM incorporating multiple cement combinations is not conclusive. This study explored the effect of the combined usage of ordinary portland cement (OPC) and sulfoaluminate cement (SAC) on the long-term performance and microstructural properties of a CAEM system in detail. Three tasks were conducted, including (1) designing six CAEM formulations by introducing different types (OPC and SAC) and contents (2–6 wt%) of cement; (2) evaluating the long-term performance by moisture susceptibility, frost damage, abrasion resistance, and rutting resistance; and (3) characterizing the microstructural properties by scanning electron microscopes and energy-dispersive spectrometers. The experimental results revealed that the relative dynamic elastic modulus of CAEM was increased to 69.7% when admixing 90 wt% OPC and 10 wt% SAC. The mixture incorporating 90 wt% OPC and 10 wt% SAC demonstrated excellent rutting resistance up to ~ 31,000 cycles/mm of dynamic stability. The improved long-term performance actually originated from the reduced voids and produced a dense microstructure. The outcomes could facilitate tailoring CEAM products with better long-term performance.

With the progress in nanotechnology, the importance of nanodimensional standards is increasing. Realizing nanodimensional standards requires multiple types of high-precision microscopy techniques. The National Metrology Institute of Japan (NMIJ), one of the research domains in the National Institute of Advanced Industrial Science and Technology (AIST), is developing nanodimensional standards using atomic force, transmission electron, and scanning electron microscopes. The current status of nanodimensional standards in NMIJ is introduced herein.

Correlative electron-photon spectroscopy without a laser The multidisciplinary ERC Starting Grant project “Quantum Coherent Control: Self-Interference of Electron Beams with Nanostructures (NanoBeam)” combines experiments and simulations to develop scanning electron microscopes into a practical tool for probing electron dynamics at the nanoscale, opening new vistas for nanotechnology and materials science.