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Meta-magnetic shape memory alloys (MMSMAs) display an abrupt change in magnetization across the martensitic transformation. Simultaneous detection and statistical analysis of the emitted acoustic and magnetic noises, accompanied with martensitic transformations are important for better understanding of the magneto-structural coupling, and for utilization of well-characterized acoustic and magnetic signals for practical applications. In the present work, characteristics of thermal, acoustic and magnetic noises, detected during martensitic transformation in the Ni45Co5Mn36.6In13.4 MMSMA single crystals, were investigated for the first time. Statistical analysis of the thermal spikes, appeared during the calorimetric measurements at low cooling rates (typically below 1 K/min) showed that the energy distributions followed a power law with e = 2.0 ± 0.3 exponent, which is in good agreement with the exponents of energy distribution of acoustic and magnetic emission events (e = 1.7 ± 0.1 and e = 1.7 ± 0.2, respectively). The above exponents were independent of the external magnetic field between B = 0 and 230 mT. Interestingly, the acoustic and magnetic exponents during cooling and heating were the same in contrast to the expected asymmetry based on the fact that the transformation demonstrates an isothermal character during cooling and an athermal one for heating. Upon interrupting cooling, and dwelling at a temperature above the martensite finish temperature, practically no acoustic and magnetic noises were detected, while upon continued cooling the noise appeared again, with the same critical exponents. This indicates that the main discontinuous events, leading to noise emissions, should be the same before and after dwelling as well as during cooling and heating. In magnetic noise measurements, under zero external field, the magnetic noise packets contained voltage peaks in the detector coils in both (positive and negative) directions. Under small external magnetic fields (between 20 and 230 mT), the activity of magnetic signals increased and the magnetic peaks, during both heating and cooling, appeared more and more unidirectional (i.e. peaks only in one direction were observed) which can be attributed to the increased magnetization of the austenite.

Chromatographic media play a crucial role in the downstream processing of biotechnology products. The physical and chemical properties of these processing aids are mostly monitored by expensive and time-consuming preparative tests, but spectroscopic techniques may also be used to measure chromatographic media samples. In this study, chromatographic media formulations used in downstream processes were investigated using attenuated total reflection Fourier transform infrared (ATR FT-IR) spectroscopy. Samples were measured both in original suspension form and after drying to examine the possibilities of a potential spectroscopic method without sample preparation. Principal component analysis (PCA) was employed to identify the spectral differences among the formulations with distinct support matrices and functional groups and soft independent modeling of class analogy (SIMCA) was performed to creating classification models for identification of chromatography media. To increase the number of samples in the SIMCA, simulated spectra were generated based on the experimental spectra. PCA models indicated that spectra of samples in original suspension form and after drying contained similar information about the chemical properties of chromatographic media samples. Moreover, during the classification of spectra based on SIMCA, both measurement techniques gave high sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) results. These results show that ATR FT-IR could be applied as a simple alternative method for monitoring the chromatography media samples. This technique is also feasible without sample preparation. Thereby the multi-hours drying steps may be omitted, the measurements can be performed in a few minutes, and the potential effects of sample preparations can be eliminated.

The Budapest Neutron Centre (BNC) is a consortium of institutes to co-ordinate research activities carried out at the Budapest Research Reactor. It hosts two neutron imaging facilities (RAD and NORMA) operated by the Centre for Energy Research, Hungarian Academy of Sciences and offers access to this scientific infrastructure for the domestic and international users. The radiography station (RAD) at the thermal neutron beamline of the reactor gives a possibility to study relatively large objects by thermal neutron-, gamma- and X-ray radiography, and to benefit from the complementary features of the different radiations. RAD is being extended in 2014 with digital imaging and tomographic capabilities. The image detection is based on suitable converter screens. The static radiography and tomography images are acquired by a new, large area sCMOS camera, whereas the dynamic radiography is accomplished by a low-light-level TV camera and a frame grabber card. The NORMA facility is designed to perform neutron radiography and tomography on small samples using guided cold neutrons. Here two non-destructive techniques are coupled to determine the chemical composition and to visualize the internal structure of heterogeneous objects. The position-sensitive element analysis with prompt-gamma activation analysis (PGAA) and the imaging with neutron radiography/tomography (NR/NT) are integrated into a unique facility called NIPS-NORMA. The goal of such a combination of these methods is to save substantial beam time in the so-called NR/NT-driven PGAI (Prompt Gamma Activation Imaging) mode, in which the interesting regions are first visualized and located, and subsequently the time-consuming prompt-gamma measurements are made only where it is really needed. The paper will give an overview about the technical details of the facilities, and the latest results of selected applications from the fields of archaeometry, engineering and material science.

The article, at first, focuses on the newly developed method for grinding of hard and brittle materials, called ELID (electrolytic in- process dressing). The secondary objective is the presentation of the Expert System (ES). ES is based on a Question-Answer format in which the system prompts the user to a series of questions about the material to be machined, manufacturing(grinding) methods, required surface roughness, etc. The answers given by the user identify a situation, and this situation will conduct to an action, finally the system offering the solution for grinding method, processing parameters, etc. The real-time measurement of key grinding process parameters as grinding forces (x, y, and z components) may be collected, displayed, stored and analysed using a PC and specialised Lab View programs.