Different Types Of Specimens Research Articles

Structural integrity analysis of notched ferritic steels operating within their ductile-to-brittle transition zone: An approach from Failure Assessment Diagrams and the Notch Master Curve

This paper provides a structural integrity assessment methodology for the analysis of ferritic steels containing notch-type defects and operating within their ductile-to-brittle transition zone. The methodology, based on the use of Failure Assessment Diagrams and the novel concept of the Notch Master Curve, has been applied to 323 experimental results performed on four different steels (S275JR, S355J2, S460M and S690Q), six different notch radii (from 0mm up to 2.0mm), two different types of specimens (CT and SENB), and three different temperatures within the corresponding ductile-to-brittle transition zone. The results validate the proposed assessment methodology.

Fibre Reinforced Concrete Class Control via Fib Model Code 2010 Approach

Fibre reinforced concrete (FRC) has wide spectrum of advantages in tunnelling. Post-cracking behaviour of FRC wasn’t taken into account by Russian engineers while structural design led to underestimation of material abilities. New approach is based on fib Model Code 2010, which provides residual tensile strength Class of FRC. Research Center “FRC” (http://rcfrc.com/) carried out tests with specimens of different types of FRC, which supported by Russian Foundation for Basic Research. Research involved different specimens – plain concrete and FRC with macro-synthetic fibre of different dosage and types. The results showed the efficiency of each type of fibre. The Class of FRC was defined for each specimen series according to results.

The effect of nanoparticles in single-lap composite joints studied by experimental and numerical analyses

This study aimed to investigate the effect of nanoparticles on the strength of single-lap nanocomposite joints. Three different types of specimens were studied, each of which contained 1 wt% of carbon nanotube in the adhesive. The adherends included three different percentages of nanoclays, namely 0, 5 and 7 wt%. The material used here was glass fibers/epoxy, with epoxy as the matrix. After fabrication of the laminates, they were stuck together by epoxy resin containing 1 wt% of carbon nanotube. Different tests were also conducted to analyze the specimens. These tests included X-ray diffraction (XRD), scanning electron microscope (SEM) and tensile test. In the XRD test, the presence of glass fiber, epoxy resin and nanoclays was verified and in the SEM test, the distribution of nanoclays into the laminates was investigated and finally the strength of the joints with different nanoparticles was examined by tensile test. In addition, a finite element (FE) analysis was also incorporated and the results of this method were verified by the experimental results. To perform the FE analysis, Young’s modulus of the laminates and the adhesive were both required. Therefore, a tensile test was conducted to obtain the Young’s modulus of the adherends and the elastic modulus of adhesive was obtained from the data existing in the literature. Finally, the results from FE analysis and the experimental tests were compared with each other and a good agreement was observed. It was finally concluded that the specimen comprised of 5 wt% nanoclays had the best performance among the three.

미생물을 활용한 지반개량제의 혼합비율에 따른 사질토의 강도개선 효과

In this study, the objective of the study is to evaluate the effect of calcium carbonate powder, produced by the microbial reactions, on the strength of soft ground (sand). To analyze the cementation effects of calcium carbonate powder produced by microbial reactions on the strength of the sand, six different types of specimens (untreated, calcium carbonate, cement, carbonate + cement (1:9, 3:7, 5:5)) were made. The specimen were tested after curing (7 and 28 days). Uniaxial compressive strengths were measured on D 5 cm × H 10 cm specimens. Based on the test results, as both the weight ratio and the curing period increase, calcium carbonate, cement, and calcium carbonate + cement specimens showed an increase in the strength. In addition, compared with the strength of the specimen with cement, the strengths of the specimens with mixing ratios of 1:9, 3:7, and 5:5 (carbonate : cement) were found to be 93.5~95.8%, 825.%, 65.2~70.6%.

Shear and mode II fracture of PUR foams

Polyurethane (PUR) foam materials are widely used as cores in sandwich composites, for packing and cushioning. They are made of interconnected networks of solid struts and cell walls incorporating voids with entrapped gas. The main characteristics of foams are lightweight, high porosity, high crushability, and good energy absorption capacity. Fracture toughness in mixed mode loading is of particular interest because foam cracking weakens the structure’s capacity for carrying loads.Present paper assesses the shear elastic (shear modulus) and mechanical (shear strength) properties of polyurethane foams. Also, three different types of specimens were used to determine mode I and mode II fracture toughness. The shear modulus, shear strength and fracture toughness increases with increasing foam density. Also the effect of loading direction and loading speed is investigated. The authors propose a micromechanical model to estimate fracture toughness based on the tensile strength of the solid material and the topology of the cellular structure.

다양한 하중경로에서의 DP980 강판의 파단변형률 예측에 관한 연구

Abstract The current study is concerned with the prediction of fracture strains for DP980 steel sheets over a wide range of loading paths. The use of DP980 steel is increasing significantly in automotive industries for enhanced safety and higher fuel efficiency. The material behavior of advanced high-strength steels (AHSSs) sheets sometimes show unpredictable and sudden fracture during sheet metal forming. A modified Lou–Huh ductile fracture criterion is utilized to predict the formability of AHSSs because the conventional forming limit diagram (FLD) constructed based on necking is unable to evaluate the formability of AHSSs sheets. Fracture loci were extracted from three dimensional fracture envelopes by assuming the plane-stress condition to evaluate equivalent plastic strains at the onset of fracture for a wide range of loading paths. Three different types of specimens -- pure shear, dog-bone and plane strain grooved -- were utilized for tensile testing to calibrate the fracture model of DP980 steel sheets. Fracture strains of each loading path were evaluated such that there shows little deviation between fracture strains predicted from the fracture model and the experimental measurements. From the comparison, it is clearly shown that the three dimensional fracture envelopes can accurately predict the onset of the fracture of DP980 steel sheets for complicated loading conditions from compressive loading to shear loading and to equi-biaxial tensile loading.

Engineering behavior and correlated parameters from obtained results of sand–silt mixtures

The results of an experimental study on sands with low-plastic silt content are presented. Flexible wall permeameter tests, drained and undrained triaxial compression tests, one-dimensional consolidation tests, and undrained cyclic triaxial tests were performed on specimens with a low plastic silt content of 0%, 15%, 30%, 40%, 50% and 60% by weight. The soil specimens were tested under three different categories: (1) at a constant void ratio index; (2) at the same peak deviator stress in a triaxial test; and (3) at a constant relative density. The results were observed to be somewhat different from previous studies with non-plastic silt content and plastic fine content. Cyclic triaxial tests showed that an increase in silt content causes a decrease in the cyclic resistance ratio with a silt content up to 40–50% and thereafter causes an increase in the cyclic resistance ratio with further increases in silt content. The results of triaxial tests indicated that the value of the peak deviator stress changed with different types of specimens, and the greater internal friction an angle has, the stronger is the liquefaction resistance. Flexible wall permeameter tests concluded that the saturated hydraulic conductivity slowly decreases with an increase in silt content in the range from 0% to 30% and considerably decreases with a silt content greater than 30%. A one-dimensional consolidation test postulated that increasing silt content decreases the coefficient of consolidation. In addition, the global void ratio did not appear to be a pertinent parameter in explaining the behavior of sand–silt mixtures, while fine content and intergranular void ratio were suitable parameters for explaining the behavior of sand–silt mixtures. Finally, correlated parameters from obtained results were also presented in this study.

Dressing of Structural Cracks using Bio Concrete

Microbiology induced cracks remediation technique is a method that has been proved beyond doubt of its efficiency. The review of literature carried out in this area indicates, that the work related to quantification of repair technique in comparison with conversional methods of repair is scarce. The investigation includes two different types of specimens namely cubes and damaged RC beams subjected to high temperature, that are already available. For the cube specimens two different water cement ratios (0.56) with normal, porous (no compaction) and cracked cubes are included. The cracking of cues is done in a pre determined way by inserting a 0.5mm thick aluminum plate to a depth of 75mm top on a 100mm size of concrete cube of m20 grade mix B. sphaericus is used for investigations. The investigation of damaged beams includes three different digress of damages namely, low medium, and high, determined by rebound hammer and Ultrasonic pulse velocity test. The comparison of results of cubes and rehabilitated beams lead to the conclusion, that the bio concrete application is the most effective one the cement mortar is the least effective method.

J2210403 フレキシブルサーミスタ用(AlTi)N薄膜/ポリイミドフィルム界面の密着強度評価 : (AlTi)N薄膜/ポリイミドフィルム界面密着機構の検討

Wurtzite (AlTi)N with high crystallinity has the NTC (negative temperature coefficient) thermistor property, which is applicable to an ultra thin temperature sensor on a thin polyimide film. The flexible sensor actually requires the mechanical reliability for operation, thus, the mechanical property, especially the toughness of the interface between an (AlTi)N thin film and a polyimide film was quantitatively evaluated by sub-micron scale fracture test. In addition, the effect of the fabrication process on the toughness was investigated with different types of specimens in order to elucidate the mechanism of the interface adhesion.

NEW FERRO-CONCRETE CYLINDRICAL BEARING ELEMENT OF COLUMNS FOR BUILDINGS AND STRUCTURES, THEIR BEARING ABILITY

Non-infringing article solution ferro-concrete cylindrical bearing element of buildings and structures column in mesh holder was proposed. It reduces the weight of the steel holder and keep the required strength values of design. Theoretical calculation of ferro-concrete cylindrical structural were proposed, which consider the bond work of the concrete core and a steel holder. Ferro-concrete design with meshed holder, occupies a middle position in meaning of strength properties, between similarly reinforced concrete and ferro-concrete designs in same time integrating itself their best qualities. Besides the main function, the meshed holder acts as a particulate reinforcement, due to the presence of volume orthorhombic cell. There is a possibility to make the necessary design stiffness characteristics when you change the cell size and tilt angle of element of cylinder. Complex experimental researches, including static and low-cycle central compression of ferro-concrete specimens of different types were conducted to verify the proposed ferro-concrete designs of a new type, as well as the theoretical calculation of a bearing capacity of ferro-concrete designs.

A multicenter prospective trial to asses a new real-time polymerase chain reaction for detection of Treponema pallidum, herpes simplex-1/2 and Haemophilus ducreyi in genital, anal and oropharyngeal ulcers

Treponema pallidum, herpes simplex virus types 1 or 2 (HSV-1/2) and Haemophilus ducreyi are sexually transmitted pathogens that can cause genital, anal and oropharyngeal ulcers. Laboratory evaluation of these pathogens in ulcers requires different types of specimens and tests, increasing the risk of improper specimen handling and time lapse until analysis. We sought to develop a new real-time PCR (TP-HD-HSV1/2 PCR) to facilitate the detection of T. pallidum, HSV-1/2 and H. ducreyi in ulcers. The TP-HD-HSV1/2 PCR was tested (i) in a retrospective study on 193 specimens of various clinical origin and (ii) in a prospective study on 36 patients with genital, anal or oropharyngeal ulcers (ClinicalTrials.gov # NCT01688258). The results of the TP-HD-HSV1/2 PCR were compared with standard diagnostic methods (T. pallidum: serology, dark field microscopy; HSV-1/2: PCR; H. ducreyi: cultivation). Sensitivity and specificity of the TP-HD-HSV1/2 PCR for T. pallidum were both 100%, for HSV-1 100% and 98%, and for HSV-2 100% and 98%, respectively. T. pallidum and HSV-1/2 were detected in 53% and 22% of patients in the prospective study; H. ducreyi was not detected. In the prospective study, 5/19 (26%) specimens were true positive for T. pallidum in the TP-HD-HSV1/2 PCR but non-reactive in the VDRL. The TP-HD-HSV1/2 PCR is sensitive and specific for the detection of T. pallidum and HSV-1/2 in routine clinical practice and it appears superior to serology in early T. pallidum infections.

Behavior of Chopped Strand Mat and Woven Roving under Bending

AbstractIn this study, lamination panels were fabricated using chopped strand mat (CSM) and woven roving fabric (WR) as reinforcement for two different types of specimens, type Eband type Pb, respectively. By a combination of plain materials composite lamination structures were formed, with [CSM/0/90/CSM]2sas an orientation layer for the structures. In this research study, the structural panel was produced by hand lay-up technique with a combination of unsaturated epoxy and polyester resin, separately. Therefore, with this publication, a characteristic combination of chopped strand mat/woven roving fabric, are presented. The experimental work for both types of specimens were performed by bending until the structure fails. The characteristics of different materials, i. e. the chemicals used and the composite lamination structure, were studied, because there are different types of damages in the structure of composite materials, such as delamination, matrix cracking, fiber-matrix damage and fiber pull-out. Furthermore, it can affect the behavior of composite materials in the whole structure. As a result, this process contributes to failure prevention, as the capabilities of the structures are known, before it can be used for any part, component or area. It was also shown that different configuration lamination layers influence the strength properties of the composite materials.

Application of Zach Phase Plates for Phase-Contrast Transmission Electron Microscopy: Status and Future Experiments

Achieving phase contrast for weak-phase objects has been the driving force for the development of physical phase plates (PP) for transmission electron microscopy (TEM). Thin-film PPs have meanwhile reached a well-developed state [1]. However, carbon-based PPs suffer from fast material degradation under intense electron irradiation which has initiated the evaluation of alternative materials [2] and other PP approaches as reviewed in [3]. In contrast to thin-film PPs, electrostatic PPs allow the variation of the phase shift which opens the possibility to optimize phase contrast for different types of specimens and facilitate, e.g., wave-function reconstruction not only of weak-phase objects [4]. Among the different electrostatic PP approaches, the Zach PP [5] appears to be most promising because it minimizes obstructing structures in the back focal plane (BFP) and, hence, artifacts induced by blockade of spatial frequencies. Substantial improvements have been made with respect to contamination and charging which yields phase-contrast TEM images with well-controlled phase shift. This was demonstrated by Frindt et al. [6] where imaging with a Zach PP yielded for the first time in-focus phase-contrast images of weak-phase objects (filamentous actin embedded in vitreous ice) with negligible artifacts.

Evaluation of Pp/Clay Composites as Soundproofing Material

Noise should be disappeared or reduced by using soundproofing materials in our daily life. Polypropylene (PP)/Clay composites are interesting because of their physical and mechanical properties dramatically increased by small quantity of clay filled in PP matrix. In this paper, different types of specimens were made at 0.9, 2.9, 4.8, 6.5, 8.2 and 9.9 wt.% of organically modified clay reinforced PP (100 gram) by solvent based techniques. A heating press and laser cutting process were used to create specimens with thickness 3 mm, diameter 29 mm and 100 mm for high and low sound frequency test, respectively. The soundproofing property was measured by sound transmission loss (TL) through impedance tube method. The measured results showed that about 7∼14.8 dB sound TL was increased for 29 mm diameter PP/Clay (6.5 wt.%) composite specimens compared with pure PP at 3200∼6400Hz. And about 3.3∼5.3 dB sound TL was increased for 100 mm diameter PP/Clay (6.5 wt.%) composite specimens compared with pure PP at 520∼640Hz. In addition, mechanical properties of this composite were measured, and TEM images were taken in order to observe the micro-structure for research on relationship between soundproofing property and micromechanism.

Polarization-Resolved SHG towards Collagen Imaging

Collagen is a triple-helix protein that self-assembles into supramolecular fibrils, essential for the biomechanical integrity and physical properties of biological tissues and organs. Second Harmonic Generation(SHG) microscopy exploits a second order nonlinear coherent optical process to image macromolecules with non-centrosymmetric structure, as collagen fibers(1). Such a label-free approach provides three-dimensional(3D) imaging of the structural organization of the collagen fibers in tissues at a sub-cellular resolution with intrinsic optical sectioning, high deep penetration and reduction of out-of-focus photobleaching and phototoxicity(2). Here, we collected the endogenous SHG signal of the collagen to evaluate the hierarchical structure, organization and orientation of collagen fibers in different types of specimen, from ex-vivo biological tissues to bioengineered samples(3). To conduct this study, we coupled a femtosecond Ti:Sapphire Chameleon Ultra II laser(Coherent, Santa Clara, CA, USA) with a Leica TCS STED-CW confocal microscope(Leica-Microsystems, Mannheim, Germany). This allowed collecting the forward, the backward SHG signal and the TPE autofluorescence of the samples(2). Moreover, we also focused our attention on the SHG signal as function of polarization states of the incoming light to distinguish among different collagen fiber types and orientations(4). Analysis of the polarization of the outcoming light and the ratio FSHG/BSHG was carried out due to its potential in providing more detailed information about the sample, for instance a relationship with the diameter and the functional and structural organization of the collagen fibers variability in various tissues. For example, this allows realizing a set of features useful to evaluate the assembly of artificial tissues depending on the scaffold role in the collagen fibers assembly when mimicking a target tissue.1. Chen X. et al. Nat Protoc. 7(4),654(2012).2. Bianchini P. et al., J. Biophotonics, 1,6(2008).3. Scaglione S. et al. Nature Sci. Rep. 2,(274): 1-6(2012).4. Odin C. et al, Opt.Express, 16,20(2008).

Effect of Strength Enhancement of Soil Treated with Environment-Friendly Calcium Carbonate Powder

This study aims to investigate the effects of the strength improvement of soft ground (sand) by producing calcium carbonate powder through microbial reactions. To analyze the cementation effect of calcium carbonate produced through microbial reaction for different weight ratios, four different types of specimens (untreated, calcium carbonate, cement, and calcium carbonate + cement) with different weight ratios (2%, 4%, 6%, and 8%) were produced and cured for a period of 3 days, 7 days, 14 days, 21 days, and 28 days to test them. The uniaxial compression strength of specimens was measured, and the components in the specimen depending on the curing period were analyzed by means of XRD analysis. The result revealed that higher weight ratios and longer curing period contributed to increased strength of calcium carbonate, cement, and calcium carbonate + cement specimens. The calcium carbonate and the calcium carbonate + cement specimens in the same condition showed the tendency of decreased strength approximately 3 times and two times in comparison with the 8% cement specimens cured for 28 days, but the tendency of increased strength was approximately 4 times and 6 times in comparison with the untreated specimen.

John W.Stirling, AlanCurry and BrianEydenDiagnostic Electron Microscopy – A Practical Guide to Interpretation and Technique (RMS – Royal Microscopical Society)John Wiley & Sons, West Sussex, UK, 2013. 468 pages. Price £71.25 (Hardback, Amazon). ISBN 978‐1‐119‐97399‐7

I first came across a pre-publication copy of this book at a conference on a trade stand and instantly knew that I wanted to read it from just having a quick flick through. This new and exciting book covers a wide range of the most common areas in diagnostic pathology at the ultrastructural level, including chapters on muscle, nerve and CADASIL. There are also extremely informative and helpful chapters about the practicalities of processing, cutting and viewing different types of specimen. Each chapter is written by specialists in that particular field. The book itself has a very pleasing lay out and text which is clear, flowing and easily accessible. The electron micrographs are numerous and high in quality, with clear and concise figure legends which are well referenced within the main body of the text. It is easy to dip in and out of and find the particular area of interest. The editors of this book state that they have not attempted to reproduce previous encyclopaedic texts of TEM in diagnostic pathology. However for a relatively small book a lot of ground is covered. Chapters cover the ultrastructural pathology of renal disease, transplant renal biopsies, skeletal muscle, nerve, tumours, microbial ultrastructure, ciliary disorders and sperm centriolar abnormalities, lysosomal storage diseases, CADASIL, platelet disorders, congenital dyserythropoietic anaemia types I and II, Ehlers-Danlos Syndrome, and occupational and environmental lung disease. I like the fact that where appropriate many of the chapters start by describing and illustrating ‘normal’ tissue, something you never normally see in diagnostic electron microscopy. The book also covers the practical aspects of electron microscopy, including how to cut up and process samples in order to gain the maximum amount of information from them. Detailed protocols are included and, having had to do TEM on a histological section on a slide for the first time recently, I can speak from experience and say that the protocols are clear, easy to follow and really do work. There is also a section on trouble shooting problems with sectioning of blocks which is useful, and a discussion of hot topics in modern diagnostic electron microscopy. This includes chapters covering digital imaging in diagnostic EM, the uncertainly of measurement and the impact of microwave technology and telemicroscopy. From a neuropathological point of view the CADASIL chapter provides a logical and practical approach for how to screen the sample for the presence of the classical GOM deposits that confirm a positive diagnosis of CADASIL. The electron micrographs in this chapter show clear examples of the GOM deposits and also show that they should not be confused with other non-specific electron dense deposits often see in samples that are submitted as possible CADASIL. The chapters on skeletal muscle and nerve cover 64 pages in total and give a good but brief overview of these tissues. The chapters cover practical aspects of how to handle and process these tissues, the ultrastructure of normal tissue, possible artefacts, and pathological changes. The chapter on lysosomal storage diseases is particularly useful for those rare occasions when you see them in clinical practice. The chapter provides a good overview of these diseases, the majority of which have CNS involvement. The chapter contains an array of electron micrographs demonstrating the ultrastructural findings of some of these diseases in skin biopsies, which are the most cost effective first line diagnostic tool in these cases. Overall I feel that this book is a valuable and useful addition to the bookshelf of anyone involved in electron microscopy who works in a diagnostic setting, be they an electron microscopist or a pathologist. It covers a lot of ground in just 468 pages. Priced at £71.25 (http://www.amazon.co.uk), it offers excellent value for money. This book is also available as a kindle edition with a price of £49.88 (http://www.amazon.co.uk). The clear explanations, electron micrographs and practical advice (that really works) make this a good all round diagnostic EM reference book. I would highly recommend it.

Discrepant Results for BRAF V600E Mutation Among Different Specimens in a Case of Hairy Cell Leukemia

Discrepant Results for BRAF V600E Mutation Among Different Specimens in a Case of Hairy Cell Leukemia

Application of BIOMED-2 primers in the detection of T cell receptor T gene rearrangements in patients with mycosis fungoides

Objective To estimate the value of BIOMED-2 primers for the detection of T cell receptor Y （TCR-y） gene rearrangements in different types of specimens from patients with mycosis fungoides （MF）. Methods Totally, 15 paraffin-embedded tissue specimens, 14 fresh tissue specimens and 18 whole blood specimens were obtained from 28 patients with MF, and subjected to DNA extraction. BIOMED-2 multiplex PCR tubes TCRy （A＋B） were used for the analysis of TCRy gene rearrangements. Data were processed by SPSS 13.0 software, and statistical analysis was done by chi-square test and Fisher＇s exact probability test. Results TCRy gene rearrangements were detected in 3 paraffin-embedded tissue specimens, 11 fresh tissue specimens and 12 blood specimens, with significant differences in the detection rate between the three samples （X2 = 13.047, P 〈 0.01 ）. The fresh tissue samples showed a significantly higher detection rate than the paraffin-embedded tissue samples （X2 = 12.523, P 〈 0.01 ）. The detection rate of TCR3＇ gene rearrangements was 3/6 in paraffin-embedded tissue samples collected in 2011, significantly higher than that in the other 9 paraffin-embedded tissue samples collected before 2011 （Fisher＇s exact probability test, P = 0.044）, but similar to that in 14 fresh tissue specimens （12/14, Fisher＇s exact probability test, P = 0.044）. Decreased detection rate of TCRy gene rearrangements was observed in blood samples compared with fresh tissue specimens, but no statistical difference was observed between the two types of specimens （X2 = 2.358, P 〉 0.05）. Conclusions BIOMED-2 multiplex PCR tubes TCRy （A＋B） are suitable for the detection of clonal rearrangements of TCRy gene in different types of specimens, especially in fresh tissue specimens, from patients with MF. Key words: Gene rearrangement, gamma-chain T-cell antigen receptor; Mycosis fungoides; Polymerasechain reaction

Influences of High-Temperature Short-Time Endurance Performance of Heat Resistant Steel for Ultra Supercritical Units

Heat-resistant steel (12%wt. Cr) used in the ultra supercritical set blade was quenched and tempered by vacuum heat treatment furnace, the mechanical properties and metallographic structures at room temperature can meet the specific requirements. However, there are some problems existed on high-temperature short-time lasting performance. To improve the high temperature endurance performance of materials, the experimental testing and analysis were carried out fro different types of specimen. The research showed that short-time rupture is a kind of creep fracture, and short lasting strength was closely related to test temperatures between laths and grain boundary and carbide coarsening. Energy spectrum analysis revealed that cast in the hole had high B element content (19.98%wt.), which meant grain boundaries of the B at high temperature began to migrate and form in the crystal B in that second phase particles are contained, and grain boundary strength was obviously decreased. The enduring high temperature experiment indicated that the strength were declined rapidly and fractured suddenly at high temperature.