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The FurnaSEM microfurnace was installed in the chamber of a scanning electron microscope to carry out in situ experiments at high temperatures and test its limits. The microfurnace was used in combination with different types of detectors (Everhart–Thornley for the collection of secondary electrons in a high vacuum, gas secondary electron detector for the specific collection of secondary electrons in the presence of gas, and Karmen© detector for the collection of backscattered electrons at high temperature). Experiments carried out on various samples (metal alloys and ceramics) show that the microfurnace operates in both high-vacuum and low-vacuum modes. Temperature ramp rates during temperature cycles applied to the sample range from 1 to 120 °C/min (temperature rise) and 1 to 480 °C/min (controlled and natural cooling). The maximum temperature at which images were recorded up to 25 k × magnification was 1340 °C, with a residual air atmosphere of 120 Pa. The choice of a flat furnace with the sample placed directly above it has enabled innovative experiments to be carried out, such as low-voltage imaging (using a shorter working distance—up to 10 mm—than is possible with conventional furnaces), 3D imaging (by tilting the stage by up to 10°), and high-temperature backscattered electron imaging (using a dedicated detector). [ABSTRACT FROM AUTHOR]

This paper describes the methodology of combining experimental measurements with mathematical–physics analyses in the investigation of flow in the aperture and nozzle. The aperture and nozzle separate the differentially pumped chamber from the specimen chamber in an environmental scanning electron microscope (ESEM). Experimental measurements are provided by temperature and pressure sensors that meet the demanding conditions of cryogenic temperature zones and low pressures. This aperture maintains the required pressure difference between the chambers. Since it separates the large pressure gradient, critical flow occurs on it and supersonic gas flow with the characteristic properties of critical flow in the state variables occurs behind it. As a primary electron beam passes through the differential pumped chamber and the given aperture, the aperture is equipped with a nozzle. The shape of the nozzle strongly influences the character of the supersonic flow. The course of state variables is also strongly influenced by this shape; thus, it affects the number of collisions the primary beam's electrons have with gas molecules, and so the resulting image. This paper describes experimental measurements made using sensors under laboratory conditions in a specially created experimental chamber. Then, validation using mathematical–physical analysis in the Ansys Fluent system is described. [ABSTRACT FROM AUTHOR]

The specific features of application of a low-energy atomic-force microscope (AFM) for studying the dynamic process of face growth in terms of the fluctuation model of crystal growth are discussed. It is shown that the probe interaction with an area of growing crystal surface on the time scale characteristic of a sequence of free energy fluctuations is a limiting factor for constructing an image of growing face surface. Agreement between the phenomenological and quantum (according to the uncertainty relation) descriptions of the effect of limiting magnification for a growing crystal face in an AFM is demonstrated. Specific features of detecting a growth stage on a crystal face using a transmission/scanning high-resolution electron microscope in a gas medium are also discussed. The effect of ultimate magnification when observing crystal growth in an АFМ is a basis for discussing the concept of the transient state of matter in the topochemical reaction of crystal growth and the phenomenon of building particle. [ABSTRACT FROM AUTHOR]

• Additive effect of thyme and betel leaf oil for C. gloeosporioides inhibition. • PVA nanofibres had oil loading capacity upto 75.88 %. • Developed nanofibres showed inhibition zone upto 24 cm in vitro. • Packing inoculated sapota with nanofibres reduced disease severity to 6.7 %. Control of anthracnose disease caused by Colletotrichum gloeosporioides by use of essential oils encapsulated in nanofibres made of polyvinyl alcohol has been attempted in this study. Essential oils from plants of subtropical origin, thyme oil and betel leaf oil were incorporated in electrospun mats at different levels. The Scanning Electron Microscope analysis revealed size of the nanofibers between 180 and 302 nm. Effective Dose (ED 50) values for the pure oils and their blends (1:3; 1:1; 3:1) ranged from 77 to 148 ppm. The blended essential oils demonstrated additive effect for inhibition of the pathogen with Abbott index >0.5. Oil loading capacity, determined using Gas Chromatography Electron Capture Detector ranged from 40.15–75.88% and was found proportional to feed content. No major effect of incorporation of thyme oil and betel oil on polymeric structure was observed in Fourier-transform infrared spectra. A Band near 876cm−1 and 1250 cm−1 signified the presence of both thyme and betel oil respectively. The composite nanofibers with blended oils at three levels showed inhibition zone from 6.6 mm to 11.6 mm on 3rdday of incubation, which increased further upto 24 mm on the 6th day. Sapota fruits inoculated with Colletotrichum gloeosporioides recorded disease severity of 83.33 %, 8.39 % and 6.72 % when packed in corrugated fiber board boxes with composite nanofibers as compared to control fruits (100 %) on the 6th day of incubation at 28 °C. Burning symptoms on skin were observed on fruits kept in contact with same level of essential oil infused sterile cotton balls highlighting the importance of encapsulated oils for disease control. [ABSTRACT FROM AUTHOR]