A Finite Element Analysis of the Effects of Graphene and Carbon Nanotubes on Thermal Conductivity of Co Phase in WC–Co Carbide

In engineering practice, the service life of cemented carbide shield tunneling machines in uneven soft and hard strata will be seriously reduced due to thermal stress. When carbon nanotubes (CNTs) and graphene nano-platelets (GNPs) are added to WC–Co carbide as enhanced phases, the thermal conductivity of carbide is significantly improved. Research should be performed to further understand the mechanism of enhancement in composites and to find ways to assist the design and optimization of the structure. In this paper, a series of finite element models were established using scripts to find the factors that affect the thermal conduction, including positions, orientations, interface thermal conductivity, shapes, sizes, and so on. WC–Co carbide with CNTs (0.06%, 0.12%, and 0.18% vol.), GNPs (0.06%, 0.12%, and 0.18% vol.) and hybrid CNTs–GNPs (1:1) were prepared to verify the reliability of finite element simulation results. The results show that the larger the interface thermal conductivity, the higher the composite phase thermal conductivity. Each 1%vol of CNTs increased the thermal conductivity of the composite phase by 7.2%, and each 1% vol. of GNPs increased the thermal conductivity of the composite phase by 5.2%. The proper curvature (around 140°) of CNTs and GNPs with a proper diameter to thickness ratio is suggested to lead to better thermal conductivity.

Curvature Measurement of Thin Plates with the Help of Digital Image Processing

The verification of different plate bending problems require a punctual measurement method of the bent shape. However, with a proper curvature measurement procedure the calculations can be made more accurate. This is due to the workaround this method provides by neglecting the inaccuracies of the beam theory and the tensile tests, measuring directly the function between the curvature and bending moment for a given sheet metal. The measurements in this paper are made with the help of a digital camera and telephotographic lens. The evaluations of these images are compared to the results obtained from the Euler-Bernoulli beam theory. While the results regarding the curvature measurements have a significant deviation, the shape of the plate is in good agreement with the numerical calculations.

Structural Basis for Capsid Recruitment and Coat Formation during HSV-1 Nuclear Egress

During herpesvirus infection, nascent viral capsids egress the nucleus into the cytoplasm by an unusual mechanism whereby capsids bud at the inner nuclear membrane. This process is mediated by the conserved heterodimeric nuclear egress complex (NEC), anchored to the inner nuclear membrane, that deforms the membrane around the capsid by forming a hexagonal array. However, how the NEC coat interacts with the capsid and how proper curvature of the coat is achieved to enable budding are yet unclear. Here, we show that the binding of a capsid protein, UL25, promotes the formation of a pentagonal rather than hexagonal NEC arrangement. Our results suggest that during nuclear budding interactions between the UL25 bound to the pentagonal capsid vertices and the NEC introduce pentagonal insertions into the hexagonal NEC array to yield an NEC coat of the appropriate size and curvature, leading to the productive budding and egress of UL25-decorated capsids.

Analiza porównawcza postawy uczniów nauczania początkowego Szkoły Podstawowej w Białych Błotach

Introduction. This research thesis analyses the screening results of Grade 1 students, beginning their education in 2013, in three consecutive years. Aim. The aim of the thesis was: to establish the incidence of abnormal curvature in the three consecutive years among elementary school students, starting school in 2013; to determine the tendencies in the development of abnormal curvature. Material and methods. The research was conducted in the Primary School in Białe Błota. It is a retrospective thesis, consisting of 120 result specimens of screening of Grade 1 students in School Year 2013/14, 118 results of Grade 2 students in 2014/15 and 119 results of Grade 3 students in 2015/16. Results. The results were presented in one group: all classes (120 students), using general statistics. Within two years of school education, most abnormal curvature occurred in Grade 2. Out of 119 students, only two were of proper curvature. Conclusions. The asymmetries in the frontal plane in most cases were preceded by other abnormal curvature types. The highest percentage refers to spine defects in the sagittal plane and the defects of legs. The most common groups of defects occurring with the two years of school education are asymmetries in the frontal plane and flat-and-claw feet. The analysis of results did not confirm the relation between the number pf sports classes and the development of abnormal curvature. Abnormal curvature developed in a similar way both among children from the sports class and the general classes.

A note on proper curvature symmetry in general cylindrically symmetric four-dimensional Lorentzian manifolds

We considered the most general form of non-static cylindrically symmetric space-times for studying proper curvature symmetry by using the rank of the [Formula: see text] Riemann matrix and direct integration techniques. Studying proper curvature symmetry in each case of the above space-times, we show that when the above space-times admit proper curvature symmetry, they form an infinite dimensional vector space. It is important to note that here we also find the case when the rank of the [Formula: see text] Riemann matrix is one and no covariantly constant vector fields exist.

PROPER CURVATURE COLLINEATIONS IN NONSTATIC SPHERICALLY SYMMETRIC SPACE–TIMES

A study of nonstatic spherically symmetric space–times according to their proper curvature collineations is given by using the rank of the 6×6 Riemann matrix and direct integration techniques. Studying proper curvature collineations in each case of the above space–times it is shown that when the above space–times admit proper curvature collineations, they turn out to be static spherically symmetric and form an infinite dimensional vector space. In the nonstatic cases curvature collineations are just Killing vector fields.