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This study presents multiphysics analyses of the electron target cooling system of the accelerator-driven system (ADS) of the Kharkiv Institute of Physics and Technology (KIPT) using MCNP and Fluent computer programs. MCNP has been used to transport electrons, gammas, and neutrons, and to calculate the energy deposition in the target materials. The MCNP mesh-tally data have been imported into Fluent by a C subroutine that has been compiled and linked to Fluent as a user-defined function. The KIPT ADS is located in Ukraine and was in operation until February 2022. The Fluent model is based on the computer-aided design files from the manufacturing process of the target assembly. The Fluent results for the reference case match very well the literature results obtained by STAR-CCM+ during the design phase. Other cases that differ from the reference one have been analyzed; in these cases, it is assumed a malfunction of the electron accelerator or of the water cooling system. The target cooling system operates normally for all the analyzed cases except when the inlet water mass flow rate is decreased. The transient analysis showed that the target cooling system can operate for 180 s with full power when the inlet water mass flow rate is decreased down by 75%. [ABSTRACT FROM AUTHOR]

CHF3/Ar plasma was used to etch LiTaO3 crystal by inductively coupled plasma technology. The etched crystals under different process parameters were analyzed by surface profilometer and characterized by atomic force microscopy and scanning electron microscope. It was shown that ICP power, RIE power, and total gas flow rate had similar effects on etching rate and selectivity, while Ar/(Ar + CHF3) gas ratio had opposite effects on etching rate and selectivity, with better etching rate and selectivity at the ratio of 0.2. Our work gives a fundamental instruction for the fabrication of LiTaO3 based devices. [ABSTRACT FROM AUTHOR]

Randomized clinical trials (RCTs) have often been considered as the gold standard in drug development, but they may not be fully powered due to limited patient population and can even lead to ethical concerns in rare disease studies. In situations like this, real-world data (RWD)/historical data can be utilized to augment or possibly serve as the control arm for the current trial. If a subset of subjects from the RWD/historical trial could be matched to the concurrent control arm subjects and they are deemed comparable following certain criteria, then pooling the matched subjects from the historical control arm and the concurrent control arm can boost the power. In this paper, we propose two matching methods of borrowing historical control data that not only balance key observed baseline covariates but also ensure the comparability of responses between the historical and concurrent controls. Close similarity in response variables among controls reduces Type I error inflation and provides further protection against unmeasured confounding bias, which is a major challenge in using RWD. Simulation studies are conducted to evaluate the empirical performance of the two matching methods in terms of Type I error rate and power, and an illustrative description of a planned study is presented. [ABSTRACT FROM AUTHOR]

Bent Laue monochromator HEX is designed with a high-energy non-focusing X-ray monochromator for full-field imaging. The following design ideas apply to the imaging monochromator: The HEX center branch, which the monochromator serves, is white-beam compatible. The monochromator is located in the first optical enclosure with the following parameters: source to monochromator distance is 31 m; monochromator to sample distance is 73 m. Diffraction Enhanced Imaging (DEI) or Analyzer Based Imaging (ABI) uses a perfect crystal monochromator and matching analyzer to achieve sensitivity to X-ray refraction and ultra small-angle scattering on the order of 0.01 micro-radians. [Extracted from the article]

CHF3/Ar plasma was used to etch LiTaO3 crystal by inductively coupled plasmas technique. X-ray photoelectron spectroscopy was performed to investigate the etching mechanism. It was found that chemical reactions had occurred between the F plasma and the Li and Ta metal species, forming the corresponding fluorides. Some fluorides are nonvolatile, and remained on the surface during the etching period. In order to get higher etching rate, it is important to remove these metal fluorides. The combination of chemical reaction and sputtered etching was performed and could effectively remove the remaining residues. [ABSTRACT FROM AUTHOR]

A Fe-based multi-component alloy, 60Fe-12Cr-10Mn-15Cu-3Mo, which presents higher yield stress than typical stainless steels (such as 304, 316, and 340), was used to investigate the thermal stability of irradiation-induced defects. Neutron irradiation was carried out at approximately 323 and 643 K using up to 1.3 × 10−3 and 4.5 × 10−4 dpa (displacements per atom), respectively. While no defects were accumulated at the high temperature of 643 K, single vacancies were formed after irradiation at the low temperature of 323 K to 1.3 × 10−3 dpa, and the vacancies became mobile at 423 K. As a result, vacancy clusters were formed. However, as the annealing temperature increased the size of vacancy clusters decreased. Coincidence Doppler broadening measurements indicated that Cu precipitates were the sites of vacancy cluster formation, and the recovery of vacancy clusters became prominent while annealing the irradiated sample at temperatures higher than 423 K. Recovery of vacancy clusters at 573 K, which was not a high temperature, was also observed even in the sample that was irradiated using 2.5 MeV Fe ions at room temperature to 0.6 dpa at damage peak. [ABSTRACT FROM AUTHOR]

Recent technological advancement in flexographic printing has allowed flexography to catch up with other R2R processes such as gravure printing in the printed electronics field. However, there are many process parameters involved in flexography that can affect the print quality. This work attempted to achieve finer line printing compared to the current 45–100 µm printed line width range of flexography by manipulating and studying these process parameters. A design of experiments was conducted to investigate the influence and interaction of various process parameters such as anilox volume, anilox force and printing force on the printed line width. After identifying the key process parameter from the design of experiments, another in-depth study of the key process parameter was conducted to further investigate how printed line width was affected. The results showed that the printing plate was elastically deformed with a range of 50–400 N printing forces. Beyond the 400-N printing force, the printing plate experienced plastic deformation. [ABSTRACT FROM AUTHOR]

Compatibility between the transformer oil and construction material should be considered in real transformer operation for equipment safety. In this study, we investigated the characteristics of the two types of naphthenic transformer oil and self-developed hydrogenated transformer oil by means of aging experiment with solid component of transformer, for instance, construction material, rubber seals, insulating varnish and insulating paper. It was suggested that the hydrogenated transformer oil performed much better in all of the compatibility tests, while the naphthenic transformer oil delivered detrimental results in rubber seal, paper degradation test and insulating varnish test. In addition, thermal stability experiment of the oil also indicated the better performance of hydrogenated oil than the naphthenic oil. This research study not only suggested the better compatibility of hydrogenated oil, but also provided the theoretical data for the potential use of hydrogenated oil in transformers. [ABSTRACT FROM AUTHOR]

Objectives: Potential gene therapy application of single and co-expression of interleukin 1 (IL-1) receptor antagonist (IL-1Ra) and transforming growth factor-β1 (TGF-β1) to alter disease progression was investigated in an in-vivo rabbit model of osteoarthritis (OA).Method: Sixteen young adult rabbits were randomly and equally divided into four groups: blank control group, IL-1Ra transfection group, TGF-β1 transfection group, and IL-1Ra/TGF-β1 double transfection group. Histological examinations were performed to monitor disease progression after haematoxylin and eosin (H&E) staining of articular cartilage. Immunohistochemistry was used to detect IL-1Ra and TGF-β1 in synovial membrane tissues. Exogenous IL-1Ra and TGF-β1 content was assessed in joint lavage fluid using an enzyme-linked immunosorbent assay (ELISA).Results: ELISA measurements from the joint lavage fluid showed high expressions of IL-1Ra and TGF-β1 in the single and double transfection groups. Remarkably, concomitant reductions in IL-1β and tumour necrosis factor alpha (TNF-α) levels were observed in these single and double transfection groups. Radioimmunoassay (RIA)-based detection showed that IL-1β and TNF-α levels in the gene transfection groups were significantly lower compared to the blank control group, in parallel experiments. Importantly, injection of IL-1Ra and TGF-β1 expressing cartilage cells into joints led to a significant inhibition of cartilage matrix degradation. Finally, IL-1Ra and TGF-β1 expression in tissues correlated with disease reversal in the experimental group, with improved tissue architecture and collagen deposition.Conclusions: Our results reveal that both single- and double-gene transfection of IL-1Ra and TGF-β1 promote extensive repair of damaged cartilage, and double transfections showed better recovery than single transfections, suggesting that co-expression of IL-1Ra and TGF-β1 inhibits degeneration and improves repair of articular cartilage in OA. [ABSTRACT FROM AUTHOR]

FeCoHfO thin films with soft magnetic properties were deposited on Si (100) substrates using radio frequency reactive magnetron sputtering in Ar+O2 gases. During the deposition process, the partial pressure of oxygen was fixed at 3%. Sputtering power and sputtering pressure varied from 50 to 350 W and from 0·2 to 1 Pa respectively. In the condition of stationary sputtering gases pressure of 0·4 Pa, it was found that the film electrical resistivity ρ decreases steeply with the increasing sputtering power, and the natural ferromagnetic resonant frequency fr and static anisotropy field Hk increase with increase in power from 50 to 250 W, and then decrease when power exceeded 250 W. The coercivity of films had a contrary trend compared with fr. At 250 W sputtering powers, the optimal properties with fr≈3·02 GHz, saturation magnetisation 4π Ms≈19·6 kGs, coercivity Hc≈2 Oe and ρ≈2200 μΩ cm were obtained. In the condition of fixed sputtering power of 250 W, fr, 4π Ms and Hk decreased with the increases in sputtering pressure; Hc and ρ had an opposite trend. The physical nature of the effect was suggested to be related to the structure and composition changes in films. [ABSTRACT FROM AUTHOR]

Diffraction enhanced imaging (DEI), also called analyzer-based imaging (ABI), cultivated within the synchrotron community, has the potential to revolutionize medical imaging through reduced dose and enhanced contrast imaging. [ABSTRACT FROM AUTHOR]

This article presents an investigation of antiadhesive coatings for nanoimprinting lithography. To get the optimum parameters of the coating process, a surface-contact angle goniometer and an atomic force microscope were used for detailed comparison of the coated surfaces produced with different process parameters. With the antiadhesive coating, the contact angle of deionized water on the mold surfaces changed from 30°-90°. The relationships between the coated surface characteristics and the coating parameters were experimentally studied. Under certain conditions, before it reached ∼90°the contact angle increased significantly with increased coating time, baking time and solution concentration. The nanoimprinting process was then performed using the mold coated with selected parameters, and the imprinting results showed that the coating was effective to reduce the interfacial forces between the mold and the polymer for nanoimprinting. The contact angle measurements and the atomic force microscope investigation showed that the antiadhesive layer had no obvious degradation after the imprinting process. [ABSTRACT FROM AUTHOR]

This work investigates the environmental impacts of three manufacturing processes for a promising biodegradable polymeric material: polyhydroxyalkanoate (PHA). The processes studied are microbial PHA manufacturing using glucose as the carbon substrate, microbial PHA manufacturing using cheese whey as the carbon substrate, and microbial PHA manufacturing using genetically engineered plants. A lifecycle model is established for each of the processes, and the Eco-indicator 99 methodology is used in the study. Results with 10 indicators under human health, ecosystem quality, and resources are obtained and compared. Because the processes are still largely under development, many lifecycle data are rare and insufficient. A number of reference sources and reasonable assumptions are used in the calculations. The study has identified the major contributors to environmental impacts, and can quantitatively explain how each impact indicator is affected by a particular process. The study provides the information for technical decision-making for the development of environmentally-friendly PHA manufacturing processes. [ABSTRACT FROM AUTHOR]

This paper presents a two-stage methodology for the optimisation of layout and path planning that can be used in flame cutting of sheet metals. The main objective of this paper is to minimise the total travel distance of the flame gun that will not only reduce the cutting time but also the heat effect. The first stage is to use a heuristic to cluster a set of small rectangular items (called workpieces) into one or more large rectangular objects (called blocks) and then best fit these blocks into a given stock. By allowing clustered small items to be cut along common borderlines, the travel distance within blocks is minimised. The second stage is to use genetic algorithms (GAs) to determine an optimal path in consideration of multiple start points for each block. The proposed path planning method provides an advantage by minimising the travel distance between blocks. The combination of the two solutions leads to minimisation of the total travel distance. To demonstrate the effectiveness of the proposed method, a number of cases are studied with results showing a 20% average reduction in the total travel distance in comparison to conventional methods. [ABSTRACT FROM AUTHOR]

We explored diffraction enhanced imaging (DEI) in both planar and computed tomography (CT) modes for early detection of beta amyloid deposition, a hallmark feature in Alzheimer's disease (AD). Since amyloid plaques precede clinical symptoms by years, their early detection is of great interest. These findings were correlated with results from synchrotron infrared microspectroscopic imaging and X-ray fluorescence microscopy, to determine the secondary structure of the amyloid beta protein and metal concentration in the amyloid plaques, respectively. [ABSTRACT FROM AUTHOR]

This article discusses the recent advances in polishing of advanced materials. Ninety-five journal articles published in 2005-2007 are briefly introduced. The topics are advances in chemical mechanical polishing (CMP), fluids for polishing, modeling of polishing, polishing of brittle materials, robotic polishing, polishing with vibrations or beams, and friction in polishing processes. CMP is perhaps the hottest research topic in the articles reviewed. Many “noncontact” processes are developed using magnetic fluids, electrorheological fluids, and abrasive flow for polishing of complicated geometries or difficult-to-approach regions. Modeling of polishing processes helps to understand the polishing mechanisms and is thus increasingly performed worldwide. More research on simulations of polishing processes can be expected in the near future. Polishing of brittle materials is also highly demanded. Automatic polishing of curved surfaces using robots and CNC machines, and polishing with vibrations and beams are promising. Investigations of friction in polishing processes help to understand the polishing mechanisms or control the polishing processes. [ABSTRACT FROM AUTHOR]

The effects of key process conditions on the protrusion of via conductors and warpage of low temperature co-fired ceramic (LTCC) substrates were investigated using the design of experiments and analysis of variance. The results revealed that tape thickness, via size and coining pressure had highly significant effects and the interaction of via size and coining pressure had a significant effect on the via protrusion heights of the LTCC samples. A combination of via size of 0.12 mm, raw tape thickness of 0.254 mm and coining pressure of 50 MPa produced minimized protrusion. Tape thickness, coining pressure and the interaction of them had highly significant effects on the warpage of the LTCC samples. A combination of tape thickness of 0.127 mm and coining pressure of 50 MPa produced minimized warpage. A combination of the factor settings was also recommended for obtaining low heights of both protrusion and warpage. [ABSTRACT FROM AUTHOR]

Turning experiments, measurements of surface roughness of the turned surfaces, and neural network computing were conducted to predict surface finish or cutting parameters for carbide and diamond turning processes. A systematic approach to obtain an optimal network was adopted with the consideration of the effects of the network architecture and activation functions on the prediction accuracy of neural networks. Analysis of variance was conducted to evaluate the significance of the effects of 3- and 4-layer networks with sigmoid and hyperbolic tangent activation functions. Trial networks were further generated for searching the optimal number of neurons in the hidden layers. The versatility of neural networks was further explored by retraining the networks by including a surface roughness parameter as one of the inputs and placing depth of cut and feed rate as the outputs, and the results were promising. [ABSTRACT FROM AUTHOR]

The effects of four key process variables on the size shrinkages of low temperature co-fired ceramic substrates were investigated using the methods of design of experiments (DOE), analysis of variance (ANOVA), and multivariable regression. The process variables investigated were raw tape thickness, laminating pressure, coining pressure, and coining time. The results revealed that coining pressure had the most significant effect on the size shrinkages of the low temperature co-fired ceramic samples under the process conditions set in this study. The average lateral size shrinkage and thickness shrinkage of the LTCC samples produced with a coining pressure of 320 MPa were significantly lower and higher than those produced with a coining pressure of 50 MPa with shrinkage differences of 3.6% and 6.2%, respectively. The effects of tape thickness, the interaction of tape thickness, laminating pressure, and coining pressure, the interaction of tape thickness and coining pressure, and the interaction of tape thickness and laminating pressure were also significant. Two regression equations were obtained and the shrinkage values could be estimated using them. The coefficients of determination R2 were 99.9% and 98.9%, respectively, and the P values were smaller than 0.001 for the two regression equations. This can allow engineers to calculate the dimensions especially lateral dimensions and features such as pad pitches at the design stage and to set the process parameters at the manufacturing stage. [ABSTRACT FROM AUTHOR]

The effects of sintering process conditions on the size shrinkages of low-temperature co-fired ceramic (LTCC) substrate were investigated. The process variables investigated were thickness of the stacked raw tapes, lamination pressure, lamination-pressure holding time, pre-heating time, debinding time, sintering dwell time, and sintering temperature ramp. Results revealed that the size shrinkage percentage of the LTCC samples in the lateral directions was always smaller than that in the thickness direction. The lateral shrinkage deviations were less than 2.1% for all the experiments conducted in this study. Pre-heating time, lamination-pressure holding time, debinding time, sintering dwell time and sintering temperature ramp had almost no effects on the lateral size shrinkage of the LTCC samples, and the average of the lateral shrinkage values was 15.3%, with a standard deviation of 0.17%. Lamination pressure and stacked raw-tape thickness had effects on the lateral size shrinkage of the LTCC samples, and empirical equations for calculation of the size shrinkage values were obtained by curve fitting. [ABSTRACT FROM AUTHOR]

In this article, a neural network procedure is suggested to inversely determine the variable binder force in U-shaped forming from the deforming shape of the part. The finite element method (FEM) is used to simulate the forming process. The inputs of the neural network (NN) model come from the deformation shape of the part. The outputs of the NN are the stepped variable binder force parameters. To reach the desired deformation, the NN model will go through a progressive retraining process. A constant binder force simulation method is also recommended to obtain the desired deformation shape. The numerical result for model NUMISHEET'93 demonstrates the efficiency of the present procedure. [ABSTRACT FROM AUTHOR]

A computational inverse technique is presented for identification of geometric parameters of drawbead in sheet forming processes. The explicit dynamic finite element method (FEM) is employed as the forward solver to calculate the maximal effective stress, maximal effective strain and maximal thinning ratio of sheet thickness for known drawbead geometric parameters. A neural network (NN) is adopted as the inverse operator to determine the geometric parameters of circular drawbead. A sample design method with the strategy of updating training sample set is developed for the fast convergence in the training process of NN model. Once the training sample set is updated, the NN structure will be optimized using the genetic algorithm (GA). The numerical examples are presented to demonstrate the efficiency of the technique. [ABSTRACT FROM AUTHOR]

It has become of paramount importance to be able to perform failure analysis of defects on hard disk surfaces quickly and accurately. In this study, ultrasonic pitting defects on hard disk surfaces were investigated. A new electrical tagging pattern system, which directly translated the channel bits to magnetic transitions during writing of the magnetic pattern around a defect, was used in the failure analysis of magnetic recording disks to mark defective sectors. With the help of the Kerr magneto-effect, the defective sectors were effectively located for further failure analysis. Results of the failure analysis revealed that there was 30% to 40% loss of the recorded magnetic bit signal due to an increase in the gap between a recording head and a hard disk surface with ultrasonic pitting defects. The experiments performed indicated that low ultrasonic power for disk cleaning could reduce the ultrasonic pitting defects significantly. The maximum failure rate due to single-type ultrasonic pitting defects was reduced from 33.4% to 16.7%, while the maximum failure rate due to cluster-type ultrasonic pitting defects was reduced from 11.1% to 5%. [ABSTRACT FROM AUTHOR]

Experiments were designed and conducted to evaluate the effects of cooling and dressing methods and five other factors on the grinding of glass. Surface roughness of the ground samples was measured and microscopic studies of the ground glass surfaces were performed. The column effect method and plotting method were applied to analyze and interpret the experimental results. The results showed that the average surface roughness heights of ground glass were improved by 5–36% and 42–52%, respectively, when an improved coolant system and dressing device were employed. The average surface roughness heights decreased by 52–58% and 30–37%, when smaller grit sizes and a resin-bond grinding wheel rather than a metal-bond grinding wheel were used, respectively. In addition, the surface roughness averages decreased by 18–23% and 13–18% when a smaller table-feed rate was used and truing of grinding wheels was performed, respectively. Moreover, compared with the surface roughness heights of the sample that was ground using the existing coolant system and manual dressing method, the surface roughness heights of the sample ground using both the improved coolant system and device-dressing method were improved by 46–70%, because of the positive interaction of these two factors. [ABSTRACT FROM AUTHOR]

The objectives of this study are to develop an ultrasonic vibration device, investigate diamond turning of an aluminium-based metal matrix composite (MMC) reinforced with SiC particles with ultrasonic vibrations applied to the cutting tool, and evaluate effects of cutting parameters on the surface finish of turned MMC samples. A low-cost, small-size vibration device was designed to mount a piezoelectric transducer and cutting tool onto a low-end CNC machine. Cutting experiments were carried out using a fractional factorial design to investigate the effects of cutting parameters. The experimental results show that surface roughness of the MMC samples cut with ultrasonic vibrations is better than that of the MMC sample cut without ultrasonic vibrations. Depth of cut and cutting speed also affect the surface finish significantly. A light dispersion phenomenon, which is not reported in other articles, is observed and explained. [ABSTRACT FROM AUTHOR]

This study aimed to develop a device to facilitate grinding experiments with microvibration for analyzing the vibration effect on surface finish of ground surfaces. A microvibration device was designed and fabricated. It can be used to provide microvibration to the workpiece vertically and/or horizontally during grinding. The relationship of the driving voltage, vibration displacement, and frequency was established. The vibration displacement of the device developed is proportional to the driving voltage amplitude for both vibration directions. The vibration frequency and displacement can be adjusted during the grinding process. Grinding experiments were carried out to compare the surface finish of silicon samples ground with and without microvibration. The results verified that microvibration of the workpiece along a certain direction during grinding can affect the surface finish of the ground workpiece. [ABSTRACT FROM AUTHOR]

This article discusses configurations of light-emitting diode (LED) light sources for visual inspection of integrated circuit (IC) packages. A package visual inspection (PVI) system with multiple LED light sources used for inspection of IC packages was designed. The image contrast changes of the sample IC packages are explained using the Torrance-Sparrow (TS) model. A few conclusions on appropriate lighting configurations for inspection of various IC packages are achieved. The TS model can be used to represent the specular lobe component. The contrast between two surfaces with different surface roughness values increases with increasing θi (incident light angle). Lighting C (θi = 75°) is recommended for packages with high surface roughness heights and resin materials. Lighting B (θi = 60°) is recommended for packages with moderate surface roughness heights and metal materials. If the background is white, the use of light sources A (θi = 15°) and B simultaneously is recommended. Light sources A and C are recommended to be chosen for packages with low surface roughness values and transparent materials. The experimental results with the actual gray-level values of the images are compared to support the conclusions. The PVI system is part of an inspection machine. All images of the sample IC packages reported in this article were obtained from an actual production line. Therefore, the results are close to those of the actual inspection situation in the manufacturing industry. [ABSTRACT FROM AUTHOR]

The deposition rate and the thickness uniformity of chemical vapor deposition (CVD) titanium nitride films depend on wafer temperatures. The heater surface conditions, such as flatness, roughness, and surface imperfections, can greatly affect heat transfer efficiency from the heater surface to the wafer, and the process performance. Because heater surface imperfections or “hot spots” that caused poor uniformity had to be eliminated, the origin of “hot spots” was identified by a detailed study of heater surface profiles. A better visualization of “hot spots” could be obtained by comparing wafer-chucking patterns with deposition patterns. Thus, the time needed to locate “hot spots” could be shortened. The manufacturing process was revised to prevent “hot spots” and improve heater performance. [ABSTRACT FROM AUTHOR]

This article presents the results of laboratory tests on four waterjet-cleaning nozzles for industrial use. The nozzles selected for the tests included standard cone-jet and fan-jet nozzles, a cavitating jet nozzle and a resonating jet nozzle. A series of cleaning and erosion tests were conducted to compare the performance of the nozzles in terms of erosion rates and jet coverage, based on the same amount of energy input. The fan-jet nozzle was extremely sensitive to small variations in standoff distance. The cavitating jet nozzle gave similar performance over a large range in standoff distance. The cavitating jet and fan-jet nozzles were more efficient at an angle of incidence of 0° and 40°, respectively. For the same settings, the cone-jet and resonating jet nozzles gave an overall poorer performance than the fan-jet and cavitating jet nozzles. The cavitating jet nozzle exhibited even better erosion rate, erosion depth, and footprint covered than the fan-jet nozzle. [ABSTRACT FROM AUTHOR]

This article studies the effect of grinding along crystallographic directions on the surface finish of single-crystal silicon. It also discusses new and/or improved processes for precision machining brittle materials, including silicon. Silicon samples were cut from (100) silicon wafers. These samples were then subjected to grinding along different crystallographic directions under the same experimental conditions. The surface roughness and the surface texture of these samples were then analyzed. The Ra and Rq values and the microphotographs of the ground silicon surfaces showed the dependency of surface finish on the grinding direction. Better surface finish was achieved when (100) silicon was ground along 〈110〉 directions. Samples ground along these directions also showed more ductile streaks on the silicon surfaces, compared with surfaces ground along the other directions. [ABSTRACT FROM AUTHOR]

The article focuses on the instrumentation, mechanism and applicability of Diffraction Enhanced Imaging (DEI) in soft tissue imaging. It offers brief information on principles and concepts of DEI including the preparation of an imaging beam, the refraction and extinction as two sources of image contrast to radiography, and the stages of scanning. It also explores the DEI imaging in breast, cartilage, and lungs.

This article reports research results on abrasive waterjet (AWJ) turning of glass. Glass rods, 25 mm in diameter, were turned by using AWJ to investigate the effects of several process parameters on the surface quality of the machined glass surfaces. The parameters studied are rotational speed, stand-off distance, water pressure, nozzle traverse speed, and abrasive flow rate. The results were also compared with those obtained from conventional machining of glass. The results showed that higher traverse rates were associated with an increase in material removal rate and thus an increase in surface roughness and waviness values. The sensitivity of surface quality to rotational speed was more than that to the traverse speed. Good surface finish was achieved at lower traverse speeds and higher turning speeds. Higher stand-off produced rougher surface finish. The best finish was generated when the nozzle consumed 300 g min-1 of abrasives. Higher pressures did not produce smoother surface finish. [ABSTRACT FROM AUTHOR]

In this study, super-smooth surfaces of oxygen-free high-conductivity copper mirrors obtained by single point diamond turning were characterized with an atomic force microscope from the three-dimensional (3D) point of view. The machining conditions were also studied. A program developed in this study for a unified approach to 3D surface finish assessment proposed by the Commission of European Community was used to obtain the 3D parameters. In two experiments, the feed rate was changed from 0.2 to 2.0 μm per revolution and 0.3 to 3.0 μm per revolution, respectively. By 3D roughness characterization of these surfaces, the optimal feed rate was found to be 1.4 μm per revolution when the cutting depth was 1 μm or 0.9–1.2 μm per revolution at a cutting depth of 2 μm, where an Sq of 2.6 and 2.3 nm could be obtained, respectively. The suggested 3D roughness characterization parameters may include Sq, Ssk, Sku, Str, Sal, SΔq, and one functional parameter, such as Sbi. [ABSTRACT FROM AUTHOR]