Papers by Keyword: Diameter

Abstract: This scientific work justifies imaging and visualization methods for analyzing heterogeneous PA-1 structures at micro- and nanoscales. It explores a key aspect of studying heterogeneous materials, namely the relationship between their microstructure and macroscopic behavior. Using Smart-EYE software, the microstructure and heterogeneous structure of PA-1 aluminum powders are justified through a range of factors. Among them, the extended functionality of the program allows for detailed analysis of particle sizes, shapes, and distribution, ensuring high accuracy and reliability of the analysis results. The capability for quick and efficient analysis of large volumes of data is also highlighted. Additionally, the software enables visualization of analysis results, simplifying their interpretation. Furthermore, the obtained results based on the histogram of particle size distribution, such as normal distribution, skewness, and modality, help avoid minor data defects and ensure proper interpretation.

Abstract: Whispering gallery mode (WGM) resonance is used for the diameter measuring method of a microsphere smaller than φ 1 mm. It is aimed to achieve measurement accuracy better than 10 nm. There are two electromagnetic modes for WGMs, and then mis-detection of the electromagnetic mode expands measurement errors more than 100 nm, so it is indispensably to distinguish the electromagnetic mode. As theoretical simulation implies, polarization mode of WGMs can be selectively excited by controlling polarization of the incident light in optical coupling. Based on the analysis, it was proofed experimentally that the polarization of WGMs could be classified. As a result, the diameter measurement for a microsphere was performed with measurement error of ± 1 nm.

Abstract: In this study, electrospun nanofibers of polyurethane were prepared utilizing a new solvent system made of chloroform/methanol. Also, we planned to assess effects of four important parameters on diameter of electrospun polyurethane nanofibers using Artificial Neural Networks (ANNs). The parameters investigated included flow rate of syringe pump, distance of spinneret to collector, applied voltage and concentration of polymer solution. Diameter of obtained electrospun nanofibers was measured using scanning electron microscopy (SEM). Results showed that flow rate and distance had reverse relation with fiber diameter, while applied voltage and concentration of polymer solution directly affected the diameter. Also, polymer concentration was shown to be the dominant factor here.

Abstract: Objective: To evaluate the fracture resistance of endodontically treated teeth reinforced with cast titanium posts and prefabricated glass-fiber posts with different diameters. Materials and Methods: 50 recently extracted human maxillary central incisors were endodontically treated and randomly divided into 5 groups of 10 specimens each: Group A: 1.35mm diameter of cast titanium post; Group B: 1.5mm diameter of cast titanium post; Group C: 1.375mm diameter of prefabricated fiber post; Group D: 1.5mm diameter of prefabricated fiber post; Group E: resin restoration. All specimens were subjected to fracture resistance testing in a universal testing machine, statistical analysis was performed and the fracture modes were analyzed. Results: The mean fracture resistance of five groups as follows: 404.22±73.92N for group A, 488.17±78.68N for group B, 280.32±45.23N for group C, 317.53±50.87N for group D, 222.76±38.67N for group E. The fracture resistance of restored teeth between group C and group D had no significant difference (P>0.05). The fracture resistance of the rest pairwise group comparisons had significant difference (P<0.05). Most of cast post samples fractured at the root middle or apical portion, while most of the fiber post samples fractured at the root cervical or post fracture, which could be retreated. Conclusion: Human maxillary central incisors restored with cast posts could bear higher fracture load and fiber post could protect the root from fracture preferably.

Abstract: This paper presents conclusions the machined surface precision of holes for steel DIN 1.4301. Based on the cutting tests, cutting speeds of 40 to 100 m/min, feed rate of 0.05 to 0.5 mm and screw drill carbide monolite. The results of the article are conclusions for working theory and practice for drilling of steel DIN 1.4301.

Abstract: Based on the working principle of the capacitive sensor, according to the requirements of deep hole diameter measuring, a capacitance probe sensor was designed, and then the design and type-selection of probe structure, cable inner structure to the capacitance probe sensor were done. At the same time, in order to overcome the measurement error caused by eccentricity, the capacitance sensor probe and inner hole of the corresponding fastener both are designed to a taper, taper positioning is relatively accurate positioning way. The design is to avoid the measurement position offset, and ensures the coaxality on the mechanical structure. The equipotential ring technology effectively overcomes the problem of edge effect of capacitance sensor, and makes the probe’s effective measurement electrode under the condition of limited long, can effectively guarantee the measure precision. By moving the capacitance probe in the hole to the different position, we will realize the deep hole diameter measurement in different cross section.

Abstract: Economical, technical and environmental advantages justify the substitution of glass fiber for lignocellulosic fibers in polymeric composites. However the uniformity of the glass fiber dimensions and composition contrast to the lignocellulosic fibers heterogeneity. In this work, a statistical analysis of the correlation between the diameter and the density of coir fiber using the Weibull methodology was performed. The diameter was obtained by profile projector measurements, while the density used precise determinations of the fibers mass and volume. The results revealed an inverse dependence between the coir fiber diameter and its density.

Abstract: According to the structure optimization of combined extrusion die, using finite element method to establish parametric model and optimize the combination die, compare the results with the result of Lame formula to prove the correctnesss of finite element method; and adjust the structure of concave of die basing the optimal result, so as to reduce the stress concentration and the maximum equivalent stress value on the concave mould, and thus the life-span of the die is prolonged.

Abstract: Used equivalent tree to construct the minimum distance diagram of triple loop networks and found the relationships between the layer of the equivalent tree and the shortest path of any two points in triple loop networks, and provided a formula to compute its average diameter. The experimental results show that average diameter approaches to a half of the diameter at the same network, in one infinite family, the diameter must obtain minimum value when average diameter obtains the minimum value, but the inverse is not. Studies also show that average diameter is the better parameter to measure transmission efficiency about loop networks instead of diameter.

Abstract: A biodegradable co-polymer, Poly (butylene succinate-co-butyene terephthalate) (PBST) was fabricated into nanofibers by electrospinning. A 4-factor 3-level L 9(3⁴) orthogonal experimental design was employed to examine the effects of process parameters on morphologies of PBST nanofibers. The results showed that the weight concentration = 13wt%, the applied voltage = 20kV, the spinning speed = 0.5ml/h, the electrode distance = 10cm and the diameter of needle = 0.7mm were identified as the optimum conditions.