Correlation Between Cutting Data Selection and Chip Form in Stainless Steel Turning

This article presents investigations related to the turning of stainless steel as a representative of difficult-to-cut materials and the effectiveness of selected chip breakers working in the local machining environment. Martensitic steel AISI 416 was used to test two commercially available types of chip breaker. The efficiency of a chip breaker working in the range of cutting conditions recommended (by the tool manufacturers) was the aim of the turning tests. As a result of the investigations an algorithm of cutting condition selection, combining both the cutting tests and the simulation procedure for the efficiency of the chip breaker was created. The vision system, equipped with a high-speed camera was used for chip form estimation. Simultaneously, the cutting force components were measured to check if the simulation calculation was correct. The FEM simulation was applied to estimate the manner in which the chip groove was filled. The article presents certain recommendations for cutting condition correction in the local machining environment for the purpose of achieving an acceptable chip form.     

Analysis of the intake of sodium with cereal products by the population of Poland

The study aimed to analyse the intake of Na with cereal products by the population of Poland. In addition, based on available literature, changes in the content of Na in bread sold in the Polish market from 2009 to 2018 were analysed with regard to Na intake reduction campaigns held in Poland since 2009 popularising information about the adverse effect of sodium on the human cardiovascular system. The results led to the conclusion that the analysed products contained 3.042 ± 3.4 g of Na per 1 kg of fresh product. The content of Na in the analysed products was bread > bread rolls > grains > pasta > rice. Cereal products provide 48.3 % of an adult’s intake of Na, where as much as 48.2 % is covered by bread, with only 0.04 % by grains, 0.04 % by pasta, and 0.01 % by rice. According to information available in reference literature from 2009–2017 the content of Na in baked goods has not been subject to significant modifications. In Poland, with regard to an excessive consumption of Na, efficient strategies must be developed to increase the awareness of consumers and to reduce the use of table salt in the most popular products, and in particular in baked goods. One of the ways to reduce the intake of Na would be consumers’ selection of an adequate range of foodstuffs naturally poor in this element or having its content reduced by means of a suitable technology. This can be a significant component of practices preventing the development of hypertension. However, the fact that information about the content of Na in cereal products is often missing from product labels makes consumer choice difficult.     

Expression of multiple apoptosis-regulatory genes in human breast cancer cell lines and primary tumors

Low molecular mass polypeptides (LMP) 2 and LMP7 and transporter associated with antigen processing (TAP) subunits TAP1 and TAP2 play a crucial role in antigen processing and cell surface expression of HLA class I molecules. Since monoclonal antibodies (mAb) to these molecules will facilitate the analysis of their expression, structure and function in normal and transformed cells, in the present study we have developed these reagents. Specifically anti-LMP2 and LMP7 mAb were generated from BALB/c mice immunized with specific peptides, and anti-TAP1 and TAP2 mAb from BALB/c mice immunized with respective recombinant proteins. mAb VF101-39F7 and VF101-39G5 were shown to be specific for LMP2, mAb VF103-5D5 and VF103-8C2 for LMP7, mAb VF108-1B3 and VF108-12D6 for TAP1 and mAb VF118-1E4 and VF118-2C5 for TAP2, since they reacted specifically with the corresponding immunogens in ELISA and with the corresponding LMP and TAP subunits when tested in Western blotting with human lymphoid cell extracts. Furthermore, the mAb immunoprecipitated components with the characteristic electrophoretic mobility from lymphoid cells. Both anti-LMP and anti-TAP mAb stained keratinocytes and infiltrating lymphocytes in frozen and formalin-fixed, paraffin embedded sections of normal skin in indirect immunoperoxidase reactions. Furthermore, all the mAb except mAb VF103-5D5 stained the cytoplasm of lymphoid cells in an intracytoplasmic staining reaction. The specificity and reactivity pattern of the mAb we have characterized indicate that they will be valuable reagents to analyze the cellular expression and tissue distribution of LMP and TAP subunits.     

Using association rules to assess purchase probability in online stores

The paper addresses the problem of e-customer behavior characterization based on Web server log data. We describe user sessions with the number of session features and aim to identify the features indicating a high probability of making a purchase for two customer groups: traditional customers and innovative customers. We discuss our approach aimed at assessing a purchase probability in a user session depending on categories of viewed products and session features. We apply association rule mining to real online bookstore data. The results show differences in factors indicating a high purchase probability in session for both customer types. The discovered association rules allow us to formulate some predictions for the online store, e.g. that a logged user who has viewed only traditional, printed books, has been staying in the store from 10 to 25 min, and has opened between 30 and 75 pages, will decide to confirm a purchase with the probability of more than 92 %.

     

Influence of aluminium electrode preparation on PCE values of polymeric solar cells based on P3HT and PCBM

The main goal of the paper was investigation of influence of aluminum electrode preparation via thermal evaporation (TE) and the magnetron sputtering (MS) on power conversion efficiency (PCE) of polymeric solar cells. The photovoltaic properties of such three kinds devices based on poly(3-hexylthiophene-2,5-diyl) (P3HT) as ITO/P3HT/Al, ITO/P3HT:PCBM (1:1, w/w)/Al and ITO/PEDOT:PSS/P3HT:PCBM (1:1, w/w)/Al were investigated. For the constructed devices impedance spectroscopy were analyzed. For devices lack of PEDOT:PSS layer or lack of PCBM, photovoltaic parameters were very low and similar to the parameters obtained for device with Al electrode prepared by magnetron sputtering. The devices comprising PEDOT:PSS with P3HT:PCBM showed the best photovoltaic parameters such as a V_OC of 0.60 V, J_SC of 4.61 mA/cm², FF of 0.21, and PCE of 5.7 × 10^?1%.     

Experimental determination of grain density function of AZ91/SiC composite with different mass fractions of SiC and undercoolings using heterogeneous nucleation model

The grain density,Nv,in the solid state after solidification of AZ91/SiC composite is a function of maximum undercooling,ΔT,of a liquid alloy.This type of function depends on the characteristics of heterogeneous nucleation sites and number of SiC present in the alloy.The aim of this paper was selection of parameters for the model describing the relationship between the grain density of primary phase and undercooling.This model in connection with model of crystallisation,which is based on chemical elements diffusion and grain interface kinetics,can be used to predict casting quality and its microstructure.Nucleation models have parameters,which exact values are usually not known and sometimes even their physical meaning is under discussion.Those parameters can be obtained after mathematical analysis of the experimental data.The composites with 0,1,2,3 and 4wt.% of SiC particles were prepared.The AZ91 alloy was a matrix of the composite reinforcement SiC particles.This composite was cast to prepare four different thickness plates.They were taken from the region near to the thermocouple,to analyze the undercooling for different composites and thickness plates and its influence on the grain size.The microstructure and thermal analysis gave set of values that connect mass fraction of SiC particles,and undercooling with grain size.These values were used to approximate nucleation model adjustment parameters.Obtained model can be very useful in modelling composites microstructure.     

Recommendation of RILEM Technical Committee 250-CSM: Test method for Textile Reinforced Mortar to substrate bond characterization

Textile Reinforced Mortar (TRM), also known as Fabric Reinforced Mortar or Fabric Reinforced Cementitious Matrix, composites are an emerging technology for the external repair and strengthening of existing structures. For most applications, the effectiveness of the TRM reinforcement relies on its bond performance. This recommendation identifies the best practice to characterize the bond behaviour of TRM. A shear bond test method is proposed to determine the peak axial stress (associated with the maximum load that can be transferred from the structural member to the externally bonded TRM reinforcement), the stress–slip relationship and the failure mode that controls the TRM-to-substrate load transfer capacity. Guidelines on specimen manufacturing, experimental setup, test execution, and determination of test results are provided.     

The Construction of Minimal DNA Expressions

We describe a formal language/notation for DNA molecules that may contain nicks and gaps. The elements of the language, DNA expressions, denote formal DNA molecules. Different DNA expressions may denote the same formal DNA molecule. We analyse the shortest DNA expressions denoting a given formal DNA molecule. We determine lower bounds on their lengths and explain how we construct these minimal DNA expressions.     

MRPC: A high performance RPC system for MPMD parallel computing

MRPC is an RPC system that is designed and optimized for MPMD parallel computing. Existing systems based on standard RPC incur an unnecessarily high cost when used on high‐performance multi‐computers, limiting the appeal of RPC‐based languages in the parallel computing community. MRPC combines the efficient control and data transfer provided by Active Messages (AM) with a minimal multithreaded runtime system that extends AM with the features required to support MPMD. This approach introduces only the necessary RPC overheads for an MPMD environment. MRPC has been integrated into Compositional C++ (CC++), a parallel extension of C++ that offers an MPMD programming model. Basic performance in MRPC is within a factor of two from those of Split‐C, a highly tuned SPMD language, and other messaging layers. CC++ applications perform within a factor of two to six from comparable Split‐C versions, which represent an order of magnitude improvement over previous CC++ implementations. Copyright © 1999 John Wiley & Sons, Ltd.     

Microstructural characterization of plasma sprayed Ln2Zr2O7 thermal barrier coatings by electron microscopy methods

The presented article characterized microstructural aspects of thermal barrier coatings (TBCs) analysis using methods of electron microscopy such as electron backscatter diffraction (EBSD), transmission/scanning electron microscopy (S/TEM), and TEM. The analyzed TBC system is based on gadolinium zirconate deposited by air plasma spraying method, and additionally, it was subjected to an oxidation test for 500 hr at a temperature of 1,100°C. Moreover, the morphological characterization of feedstock powder was showed. EBSD analysis revealed the inhomogeneity of feedstock materials in the form of complex phase composition. In the case of deposited coating, this method was used to characterize the crystallite size of zirconate coating and phase composition of thermally grown oxide zone. S/TEM and TEM analysis showed morphological details of this zone but not revealed such phase as perovskite oxide of GdAlO₃ type.