bluuebunny/crossref_metadata_2025 huggingface dataset:
Microstructural Stability of M5™ Alloy Irradiated up to High Neutron Fluences
Authors: Doriot S , Gilbon D , Béchade J-L , Mathon M-H , Legras L , Mardon J-P
Published: August 2005

The present paper is focused on the microstructural stability of the Framatome-ANP M5™ (Zr-1%NbO) alloy. Thin foils were cut from M5 cladding tubes irradiated from 1 to 6 annual cycles in EDF PWRs, and examined by analytical transmission electron microscopy (TEM). The results show that within the wide range of irradiation conditions investigated, the initial β-Nb particles undergo no amorphisation and only minor evolutions in size distribution, number density, and composition. Finally, very few c component basal loops were detected, so that no sign of accelerated growth regime has to be feared for the fuel burn-ups currently considered (∼70 GWd/t) for PWRs.

In the second part of this paper, other industrial or experimental alloys (Zy-4, M4, Zr-2.5%Nb, ZrNbSnFe) are considered to improve our knowledge about the irradiation-induced evolution of β-Nb and other minor SPP. Thin foils were cut from specimens irradiated in PWRs or MTRs (OSIRIS, SILOE) and also examined by transmission electron microscopy. In addition, Small Angle Neutron Scattering (SANS) was used to provide quantitative and statistical information on the radiation-enhanced precipitation of β-Nb needles and possible other defects or solute clusters. All these results allow a general discussion of evolution of SPP with regard to their initial structure and composition, and of the noteworthy irradiation stability of the M5™ up to high neutron fluence with respect to other alloys.
In-Core Tests of Effects of BWR Water Chemistry Impurities on Zircaloy Corrosion
Authors: Shimada S , Cheng B , Lutz D , Kubota O , Ichikawa N , Ibe H
Published: August 2005

There have been several cases of fuel failures resulting from localized corrosion acceleration of the Zircaloy-2 cladding in BWRs over the last 25 years [1–3]. Some of the failures resulted from localized crud deposition, but others appear to be related to accelerated corrosion of the cladding, possibly due to certain chemical attacks of the cladding. The corrosion variability of Zircaloy-2 in BWRs has been attributed to a synergistic effect of Zircaloy-2 material variability, water chemistry impurities, and in-core service duty. Through extensive research efforts, the susceptibility of Zircaloy-2 cladding to nodular corrosion has been mitigated through improvements in the thermo-mechanical processing and surface finish since the mid-1980s. However, isolated cases of enhanced nodular corrosion have been reported recently in US BWRs [3]. Since such corrosion variability of Zircaloy-2 is undesirable, particularly for high burnup fuel components, candidate new Zr-alloys that are expected to have better nodular corrosion resistance than Zircaloy-2 have been developed [4–6].
Atomic-Scale Simulation of Defect Cluster Formation in High-Energy Displacement Cascades in Zirconium
Authors: Voskoboinikov RE , Osetsky YN , Bacon DJ
Published: August 2005

A systematic study of damage in high-energy cascades in Zr with primary knock-on-atom (PKA) energy up to 25 keV has been carried out by molecular dynamics (MD) over a temperature range from 100–600 K. The high number of simulations for each condition of temperature and energy has revealed the wide variety of defect clusters that can be created in cascades. Mobile or sessile, two-dimensional (2D) or three-dimensional (3D) clusters of both vacancy and interstitial type can be formed. The population statistics of clusters of each type and the fraction of vacancies and self-interstitial atoms (SIA) in clusters, were obtained, and their dependence on the temperature and PKA energy were investigated. Both vacancy and SIA clusters can be mobile. However, depending on their type, self-interstitial clusters exhibit one-dimensional, planar, or three-dimensional motions, whereas vacancy clusters of only one type can glide in one dimension only. We have also performed separate MD simulations of some SIA and vacancy clusters to study their thermal stability and possible transformations.
Effects of Proton Irradiation on Reactor Pressure Vessel Steel and Its Model Alloys
Authors: Shibamoto H , Kimura A , Hasegawa M , Matsui H , Yamaguchi S
Published: August 2005

Effects of proton irradiation on the reactor pressure vessel steel (RPVS), A533B cl. 1 have been investigated by means of positron lifetime and Vickers hardness measurement in comparison with those of the iron-copper model alloys. The specimens were irradiated with 1 MeV proton up to a fluence of 3 × 1017 ions/cm2 (0.2 dpa, displacement per atom, at a peak) at temperature below 80°C. The recovery behavior of the irradiation effects was also investigated during isochronal annealing for 30 min with a 25°C step from 100°C to 650°C. By positron annihilation technique, it was recognized that microvoids, which consist of about 5 vacancies with the number density of the order of 1016 /cm3, were formed by the irradiation. The number of microvoids decreased after a low temperature annealing and completely annihilated at 250°C, although irradiation hardening still remained. A large portion of the hardening recovered by the annealing up to 300°C and almost annealed out at 450°C. Irradiation response and its recovery behavior of A533B RPVS were discussed compared to the result of Fe-based model alloys.
Injury Rates and Injury Types in Alpine Skiing, Telemarking, and Snowboarding
Authors: Ekeland A , Sulheim S , Rodven A
Published: August 2005

A central ski patrol-based registration of skiing and snowboarding injuries was performed by the Norwegian Ski Lift Association during the winter seasons 2000/2001 and 2001/2002. A control material of 3002 randomly sampled uninjured skiers was collected from the same ski resorts throughout the 2001–2002 season.

6138 injured skiers/snowboarders and 4 167 476 skier/snowboarder days were recorded during the two seasons, giving an injury rate of 1.5 injured per 1000 skier/snowboarder days. Most of the injuries occurred during alpine skiing (49%) and snowboarding (45%), whereas telemark skiing accounted for 6% of the injuries. The injury rate for snowboarders (2.3 injuries per 1000 skier days) was significantly higher than that of alpine skiers (1.1) and telemarkers (0.7) (P < 0.001). Wrist injuries were common among injured snowboarders (26%) compared to only 4% for alpine and telemark skiers (P < 0.001). Snowboarders also suffered more arm and back injuries than alpine skiers and telemarkers (P < 0.001). The knee was the main injury location in alpine skiers (28%) compared to 13% among telemarkers and only 6% among snowboarders (P < 0.001), but the percentage of knee injuries was almost twice as high for females compared to males in alpine skiers and snowboarders (P < 0.001).

As percent of all injuries injured snowboarders suffered more fractures (33%) than alpine (20%) and telemark skiers (19%) (P < 0.001), but fracture of the lower leg was uncommon among snowboarders (1%) and telemarkers (3%) compared to alpine skiers (6%) (P < 0.001). Lower leg fractures accounted for 3% of the injured alpine skiers 20 years and older compared to 5% for adolescents aged 13–19 years and 17% for children 12 years and younger (P < 0.001).

Beginners had an injury rate 3 times that of expert skiers/snowboarders (P < 0.001), and use of a protective helmet reduced the injury rate P < 0.001).

In conclusion, snowboarders had a higher injury rate then alpine skiers and telemarkers. Beginners had an injury rate 3 times that of experts, and use of protective helmet reduced the injury rate. Injured alpine skiers were most prone to knee injuries, and lower leg fractures were still a common injury in children. Injured snowboarders were most prone to suffer wrist, arm, and back injuries. The percentage of knee injuries among females was almost twice that of males in alpine skiers and snowboarders.
Residual Stress Measurements in Welded and Plastically Deformed Target Structural Materials
Authors: Roy AK , Venkatesh A , Dronavalli S , Marthandam V , Wells D , Selim F , Rogge R
Published: August 2005

Transmutation of spent nuclear fuels (SNF) is currently being considered to transform long-lived isotopes to species with relatively short half-lives and reduced radioactivity through capture and decay of minor actinides and fission products. This process is intended for geologic disposal of SNF for shorter durations in the proposed repository at the Yucca Mountain site. The structural material (Type 304L stainless steel/Alloy EP-823) surrounding the transmutation target will be subjected to welding operation and plastic deformation during fabrication, which could induce residual stresses in it. Destructive ring-core, and nondestructive x-ray diffraction, neutron diffraction, and positron annihilation spectroscopic techniques were used to evaluate residual stresses in welded and cold-worked specimens of both materials. The results indicate that, in general, for a welded specimen consisting of Alloy EP-823 and Type 304L stainless steel on opposite sides, compressive and tensile residual stresses were observed in the former and latter materials, respectively. However, a welded specimen consisting of only Alloy EP-823 on both sides showed tensile residual stresses. The extent of residual stresses in cold-worked specimens was enhanced with increased level of cold-reduction. In case of a bent specimen, compressive and tensile residual stresses were noticed in the convex and concave sides, respectively.
Effect of Surface Reaction Layer on Three-Point Flexure Bond Strength of Resin Composite to Cast Ti and Ti-6Al-7Nb
Authors: Watanabe I , Liu J , Saimoto A , Griggs J , Okabe T
Published: August 2005

This study investigated the effect of the α-case on the three-point flexure bond strength of resin composite to different thicknesses of cast CP Ti and Ti-6Al-7Nb. Cast plates (0.3, 0.5, and 0.7 mm thick) were prepared for each metal. Plates without α-case were also prepared for the 0.5 and 0.7 mm-thick CP Ti and Ti-6Al-7Nb. After resin composite was polymerized on the plates, the resin/metal specimens were subjected to three-point bending testing. The fracture force (N) and deflection (mm) at fracture were recorded. The fracture force of the specimens increased with increasing specimen thickness. Specimens without α-case withstood greater fracture force than specimens of either metal with α-case. CP Ti and Ti-6Al-7Nb without α-case deflected more than with α-case. The results suggested that the bonding between the veneer composite and thin cast structures (<0.5 mm) is likely to fail and that the surface reaction layer (α-case) should ideally be removed.
Comparison of the Corrosion Fatigue Characteristics of CP Ti-Grade 4, Ti-6Al-4V ELI, Ti-6Al-7Nb, and Ti-15Mo
Authors: Roach MD , Williamson RS , Zardiackas LD
Published: August 2005

The purpose of this study was to evaluate and compare the corrosion fatigue (CF) characteristics of a series of titanium alloys including Grade 4 CP Ti (ASTM F 67), Ti-6Al-4V (ASTM F 136), Ti-6Al-7Nb (ASTM F 1295), and Ti-15 Mo (ASTM F 2066). Evaluation of alloy composition, microstructure, and Vicker's microhardness was performed to ensure that each material met the required specification. Smooth and notched CF tensile samples of each alloy were machined using low stress grind techniques and tested at 1Hz according to ASTM F 1801 in both Ringer's solution and distilled/deionized water at 37°C. Smooth CF samples had a 10 mm gauge length and a 2.5 mm gauge diameter, and notched CF samples had a 2.5 mm notch root diameter (Kt=3.2). A minimum of three samples was tested at five tension-tension sinusoidal load levels including a run-out level at 106 cycles. SEM analysis was performed on the fractured surfaces of representative samples of each alloy to characterize and compare the failure mechanisms.

Fatigue results revealed no differences between the smooth and notched samples of each alloy run in distilled water and those run in Ringer's solution. Results indicated corrosion fatigue mechanisms were not contributing to the fractures under these conditions. However, a significant reduction of fatigue strength was observed for the notched samples of each alloy compared to the smooth samples in identical solutions. These results suggest that even though there is no notch sensitivity in these alloys under static conditions, a notch under dynamic fatigue mechanisms may cause a substantial reduction in cycles to implant fracture. SEM analysis showed typical fatigue fracture morphologies on both the smooth and notched samples. Notch samples, however, did show more defined fluting in terracing due to the higher tri-axial stress state at the root of the notch. In conclusion, corrosion fatigue mechanisms were not contributing to the fracture of these alloys under the given conditions, but the presence of a notch significantly reduced the fatigue strength of all alloys tested.
A Methodology to Fabricate Titanium and Stainless Steel Wear Debris for Experimental Use: A Comparison of Size, Shape, and Chemistry
Authors: Sprecher CM , Kunze J , Burian B , Villinger N , Jacobs JJ , Schneider E , Wimmer MA
Published: August 2005

It is well established that particulate debris can cause osteolysis. The current paper describes a simple procedure to generate titanium and stainless steel particulates for in vitro and in vivo use.

The ‘wear generator’ consisted of three pins out of titanium or stainless steel fixed onto a stir “bar.” The bar was rotated in a beaker filled with Ringer's solution against a disk of the same metal. The extracted particles were described using scanning electron microscopy, X-ray diffraction analyses, and inductively coupled plasma - optical emission spectroscopy. In addition, the chemical stability of the generated particles was tested.

The Equivalent Circle Diameter of stainless steel particles was smaller than that of titanium. Titanium particles contained pure titanium metal and titanium oxides. In contrast, stainless steel particles contained soluble corrosion products (e.g., nickel) and other elements from the salty lubricant.
ASTM Symposium on the Recovery and Enumeration of Mycobacteria from the Metalworking Fluid Environment
Authors: Passman FJ
Published: August 2005

Since 1994, when the first documented hypersensitivity pneumonitis cluster was reported at a metalworking plant, there have been approximately 200 diagnosed cases of hypersensitivity pneumonitis within the metalworking industry. Although there are a variety of bacterial and fungal etiologic agents associated with hypersensitivity pneumonitis, metalworking industry stakeholders have focused their attention on a hypothesis that links Mycobacterium immunogenum exposure to the disease.

A number of barriers confound attempts to test this hypothesis. Today's symposium opens a dialogue on two significant barriers. There is no consensus practice for sampling and recovering Mycobacterium immunogenum from either bulk metalworking fluids or metalworking fluid aerosols. There is no consensus method for quantifying mycobacteria that may be present in either bulk fluid or aerosol samples.

This paper provides a context for the symposium's other presentations. After offering a brief overview of the history of hypersensitivity pneumonitis in the metalworking environment, the author will address the current state of knowledge regarding Mycobacterium immunogenum distribution in metalworking fluids. Finally, the author will summarize the three primary strategies for enumerating mycobacteria: microscopic examination of acid-fast stained preparations, viable counts, and non-conventional methods.
Evaluation of Fatigue Crack Thresholds Using Various Experimental Methods
Authors: Forth SC , Newman JC , Forman RG
Published: August 2005

The accurate representation of fatigue crack threshold, the region defining crack growth as either very slow or nonexistent, is extremely important. If the experimentally measured threshold is unconservatively high, a structural component designed with this data may fail long before the fatigue analysis predicts. The fatigue crack growth threshold is experimentally defined using ASTM standard E 647, which has been shown to exhibit anomalies. Alternate test methods have been proposed, such as the constant Kmax test procedure, to define the threshold regime without ambiguity. However, only the current test method defined by ASTM is designed to produce the range of fatigue crack thresholds (e.g., low and high R) needed to characterize an acrospace loading environment. It is the scope of this paper to determine the fatigue crack growth threshold of a well characterized aerospace alloy, 7075-T7351 aluminum, using different methods, to compare the results, and to draw conclusions.
High Throughput Flammability Characterization Using Gradient Heat Flux Fields
Authors: Gilman JW , Davis RD , Shields JR , Harris RH
Published: August 2005

The quest for small-scale flammability tests useful for predicting large-scale fire test performance is an enduring undertaking. Often, this work is motivated by limited access to larger quantities of samples, in the case of materials development efforts, and by the slow turn-around and high cost of large scale flammability testing. Use of Cone calorimeter data such as heat release rate (HRR) and ignition data has been coupled with various models to attempt to predict the performance of materials in medium and large scale fire tests. In some instances this has been successful; however, the extensive amount of data that needs to be acquired has motivated the High Throughput (HT) Flammability program at the National Institute of Standards and Technology (NIST) to develop flammability characterization methods which significantly increase the rate of data generation. The goal is to keep pace with our sample preparation rate, which is a significant challenge since our capability to produce samples, either extruded rod, or gradient coatings, has developed to a rate of one sample per minute! The efforts described here are those specifically focused at developing HT flammability analysis methods. The method of evaluating the flammability of a sample at a variety of fluxes simultaneously involves use of a radiant panel to create a gradient heat flux field. Samples are ignited in the high flux region and burned until they self-extinguish. The local flux at this position is termed the minimum flux for flame spread (MFFS). The same general technique has also been accomplished on a smaller scale using the Cone calorimeter. Here MFFS and HRR can be measured concurrently.
Reference Impact Specimens Made from Low Carbon Steel: Report on Production and Use
Authors: Heping L , Xing Z
Published: August 2005

This paper describes a method of producing reference specimens from low carbon steel and reports the results of a national proficiency testing by 45 laboratories. The reference impact specimens of low carbon steel are much cheaper than the traditional ones, and the proficiency testing proved that the specimens are valid for finding out the problems of impact machines. Furthermore, the data showed that an impact machine would represent the similar relative bias at a different energy level of reference specimen, so it is sufficient to use reference specimens with one absorbed energy level to verify impact machines annually.
Impact Characterization of Sub-Size Charpy V-Notch Specimens Prepared from Full-Size Certified Reference Charpy V-Notch Test Pieces
Authors: Lucon E , Puzzolante J-L , Roebben G , Lamberty A
Published: August 2005

To investigate the feasibility of the production of sub-size Charpy reference test pieces, tests were performed on sub-size samples (3 × 4 × 27 mm3) carefully machined from full-size (10 × 10 × 55 mm3) Charpy V-notch certified reference test pieces. The measured absorbed energy (KV) values indicate a highly satisfactory homogeneity of the sub-size specimens. Sub-size specimens were prepared from full-size reference test pieces of 30, 60, 80, 120, and 150 J nominal absorbed energy; and values between 2 J and 7.2 J were obtained, covering almost fully the range of interest for sub-size Charpy tests. A linear relationship is observed between the KV values of sub-size and full-size samples of the same material.
Extrapolation of Fracture Toughness Data for HT9 Irradiated at 360–390°C
Authors: Gelles DS , Kurtz RJ
Published: August 2005

Following irradiation in the FFTF-AC01 test at 360°C to 5.5 × 1022 n/cm2, two HT9 samples tested at 30°C were measured to have fracture toughness levels of 28.2 and 31.9 MPa m1/2, respectively, whereas a third identical specimen tested at 205°C gave 126 MPa m1/2. Based on testing of notched tensile specimens from the same irradiation test, the low toughness was a result of brittle fracture. A similar low level of toughness has also been demonstrated in HT9 following irradiation at 250°C, and therefore such behavior is reproducible. Using ASTM Standard E 1921-02, which characterizes the fracture toughness of ferritic steels that experience onset of cleavage cracking at instabilities, it is shown that these data can be analyzed by a Master Curve approach, and that the trend of the fracture toughness over a wider range of temperatures can be estimated. Master Curve analysis demonstrates that toughness will remain low over a wide range of temperatures near 30°C, but will degrade only slightly when temperatures drop to −10°C.
Protective Window Safety Films: A Case Study in ASTM All-Hazard Building Code Standards
Authors: Grosskopf KR
Published: August 2005

As the most vulnerable component in the building envelope, fragmentation failure of glazing systems is among the leading cause of injury and death during terrorist and storm events. As a result, safety films have gained popularity as a cost-effective alternative to high-strength or laminated glass, especially for building retrofits. Various combinations of wet glazed films and mechanical attachment systems, including those satisfying ASTM F 1642 for glazing systems subject to airblast loadings, have been shown to meet windload and debris impact standards, including ASTM E 1996 standards adopted by the International Building Code (IBC). Defining these and other synergies that may exist between ASTM F -series security standards and more traditional ASTM standards that address natural hazards such as wind and seismic loading may be key in introducing anti-terrorism provisions to the commercial building industry. Such an “all-hazards” approach may compliment efforts underway to introduce meaningful terrorism resistant building standards into the IBC and minimize potential code duplication.
Ethylenediamine Alkoxylates and Their Use as Adjuvants in Glyphosate Formulations
Authors: Elsik CM , Stridde HM
Published: August 2005

N-phosphonomethylglycine (glyphosate) is firmly established as the preeminent herbicide of choice in a wide range of applications for the crop protection industry. It is well known that the efficacy of glyphosate can be enhanced with the use of surfactant adjuvants. Surfactants based on amine chemistry seem to work especially well, and an adjuvant that has found widespread use in glyphosate is the tallowamine ethoxylate. While tallowamine ethoxylates provide excellent efficacy, they also have several limitations. They raise irritancy concerns and limit the maximum loading of glyphosate in the formulation concentrate.

It has been found recently that ethylenediamine alkoxylates can be used as effective adjuvants in glyphosate formulations. Specifically, they can be used in blended adjuvants for several functions. They allow a higher glyphosate loading over that provided by tallowamine ethoxylates alone. They also reduce the toxicity profile of the glyphosate formulation significantly. Ethylenediamine alkoxylates have passed EPA inert reassessment and are listed on the new 40CFR 180.960 “Polymers; Exemptions from the Requirement of a Tolerance.” This paper will discuss the utility of this new class of glyphosate surfactants.
Effects of Proposed Well-Graded Aggregate Gradations on Frost Durability of Concrete
Authors: Dilek U , Leming ML
Published: August 2005

More stringent gradation requirements than found in ASTM C 33 are sometimes specified to provide a more well-graded particle size distribution, presumably reducing voids, improving workability, thereby reducing water demand, and requiring less cement. Little information is available regarding the effects of gradation on frost durability. A two-phase study examined the effects of selected aggregate gradations on water demand, selected mechanical properties, and deicer salt scaling resistance. In the first phase, the effects of the “8-to-18” combined aggregate gradation, using crushed stone and natural sand, were examined. In the second phase, the effects of fine aggregate gradation were examined for manufactured sands with different angularities. This study found that water demand and deicer salt scaling were both compromised using the “8-to-18” approach. Little, if any, real difference in water demand and scaling resistance between well-graded and uniformly graded manufactured sands was found, however, angularity did have a significant effect.
Adhesive Bonding and Performance Testing of Bonded Wood Products
Authors: Frihart CR
Published: August 2005

Despite the importance of durable wood bonds, the factors that lead to durability are not well understood, and the internal forces exerted upon the bondline are often overlooked. Durability requires that the bonded assembly resist dimensional changes of wood with fluctuation of wood moisture levels. Both bonding and bond breaking steps need to be understood at cellular and nanoscale, in addition to the larger spatial scales normally examined. With both internal and external forces being significant, interphase and bulk adhesive properties need to be better understood. Systematic studies of the bonding process, the forces upon the bondline, and the locus of failure using different types of adhesives and wood species should improve our ability to design wood adhesives. Modifications of wood surfaces, along with spectroscopic and microscopic analyses, are important tools to understand bond formation and failure.
Characterizing Dynamic Fracture Behavior of Adhesive Joints under Quasi-Static and Impact Loading
Authors: Simón JC , Johnson E , Dillard DA
Published: August 2005

An experimental evaluation of the dynamic fracture properties of an automotive epoxy is presented. Pronounced stick-slip behavior was observed in both quasi-static and impact tests of aluminum and composite adherends bonded with this adhesive. An experimental technique for conducting low speed impact of adhesively bonded automotive composite joints is presented. Based on the use of a modified drop tower, mode I, II, and mixed mode values for critical energy release rate were determined to create a fracture envelope for the composite/epoxy system. Because load measurements are erratic and unreliable at higher test rates, displacement-based relationships were used to quantify these energy release rates. Displacement data were collected with an imaging system that utilizes edge detection to determine displacement profiles, end displacements, and opening displacements where applicable. Because of the resolution of the image-based approach being used, determining crack length experimentally is difficult. As a result, numerical methods based on edge detection algorithms were developed to objectively determine the crack length based on the available experimental data in mode I, II, and mixed mode I/II configurations.
Rapid Determination of Sulfur in Liquid Hydrocarbons for At-Line Process Applications Using Combustion/Oxidation and UV-Fluorescence Detection
Authors: Tarkanic S , Crnko J
Published: August 2005

With the reduction in sulfur levels in gasoline and diesel products, it is necessary to have a method available which can precisely and accurately measure the very low levels of sulfur in these fuels. ASTM test method D 5453, Sulfur by Combustion and Ultraviolet Fluorescence (UVF), is a laboratory-based technology that has been widely used in the industry for such purposes for more than a decade. An on-line/at-process version of this technique is described which can complete a fast analysis in less than one minute. Thus, near real-time data can be obtained when refineries and terminals need to make rapid determinations of sulfur levels for process control and pipeline distribution decisions involving the new generation “clean” hydrocarbon fuels. Particularly discussed is the advantage gained for decision making involving detection of transport boundaries and related custody transfer issues.
Wear Behavior of Niobium Boride Coatings
Authors: Ingole S , Liang H , Usta M , Bindal C , Ucisik AH
Published: August 2005

Boride coatings on corrosion resistant refractory metals are potentially used as implanting materials. In this research, we investigated wear mechanisms of boride coatings on pure niobium using a pin-on-disk tribometer. Surface morphology studied using scanning electron microscope shows the compressed boride layer with indistinguishable regions such as coating intermediate transition layer and the substrate. The surface analysis after wear tests was conducted using an atomic force microscope (AFM). It was found that the boride coating underwent deformation wear, and debris formed and accumulated at both ends of the track due to adhesion.
Determination of Crushing Strength of Cenospheres
Authors: Bartake PP , Singh DN
Published: August 2005

Cenospheres are being used in various industrial applications mainly due to their low density, high crushing strength and good thermal and electrical insulation properties. However, for better and most effective usage of cenospheres as a filler material, it is essential to determine their crushing characteristics. With this in view, efforts were made to develop a methodology which can be employed for determining crushing strength of cenospheres easily. Details of the methodology are presented in this technical note, and its efficiency has been demonstrated by conducting pycnometric studies on cenospheres.
Fatigue Testing of Bone Cements — Comparison of Testing Arrangements
Authors: Soltész U , Schäfer R , Jaeger R , Gopp U , Kühn K-D
Published: August 2005

Bone cements are a common tool for the fixation of high load bearing endoprostheses. One of the most important requirements for their safe function is sufficient strength under long-term loading conditions. Therefore, fatigue investigations are being performed increasingly in addition to the usual characterization by quasistatic tests. Meanwhile, such fatigue testing methods are also discussed by the responsible ISO-committee. Three testing procedures are considered: a 4-point-bending arrangement, a pure tensile test with flat tapered specimens, and a uniaxial tension/compression test with cylindrical tapered samples. Until now, a direct comparison of these three methods has not been conducted. The aim of this study is to compare the three procedures with respect to their applicability for the assessment of the fatigue properties of bone cements. Whereas tension/compression leads to uncertainties in the interpretation of the results, it turns out that bending and pure tension deliver consistent evaluations. With respect to practicability, simplicity, and costs, the bending test method, which is already standardized for the quasistatic testing of bone cements, is the preferred fatigue testing method.
Protein C Inhibitor Expression by Adult Rat Sertoli Cells: Effects of Testosterone Withdrawal and Replacement
Authors: Anway Matthew D. , Show Matthew D. , Zirkin Barry R.
Published: August 2005

ABSTRACT: Protein C inhibitor (PCI), a member of the plasma serine protease inhibitor family, has been reported to be abundantly expressed in the seminal vesicles and testes. In this study, we examine the localization and regulation of the PCI gene and protein expression in testes and freshly isolated Sertoli cells from control rats, rats treated with luteinizing hormone‐suppressive testosterone/estradiol (TE)‐containing Silastic capsules for 7, 14, 28, and 56 days, and rats treated with TE for 56 days, followed by high levels of testosterone for 7 or 14 days. The administration of the TE capsules for 56 days resulted in reduced testicular testosterone, from approximately 100 ng/mL in the controls to approximately 10 ng/mL, accompanied by a 73% reduction in testicular weight. PCI mRNA levels in freshly isolated Sertoli cells were reduced by 30% and 54% following TE treatment for 28 and 56 days, respectively. When rats that had received TE capsules for 56 days were provided replacement testosterone, there was a 40% increase in PCI mRNA levels within 7 days in the absence of any change in testicular weight, and PCI mRNA levels returned to control values by 14 days. The decrease in PCI mRNA levels in TE‐treated rats was paralleled by a decrease in PCI protein levels in whole testis lysates and in seminiferous tubule fluid (STF). Protease activity was significantly increased in STF following 56 days of TE treatment. Taken together, these results indicate that 1) PCI in the testis is expressed by Sertoli cells; 2) the testicular expression of PCI is responsive to intratesticular testosterone levels; and 3) protease activity within the seminiferous epithelium is elevated when intratesticular concentration is decreased, perhaps as a consequence of decreased PCI.
Maculopathy in a 52-Year-Old Patient With Diabetes
Authors: Kwok Alexander , Ercanbrack Carson , Uwaydat Sami
Published: February 2024

A 52-year-old woman with severe nonproliferative diabetic retinopathy had decreased vision and macular edema in both eyes that was not responding to treatment. What would you do next?
Development of an algorithm for biomedical image analysis of the spatial organization of collagen in breast cancer tissue of patients with different clinical status
Authors: Lukianova Nataliia , Mushii Oleksandr , Zadvornyi Taras , Chekhun Vasyl
Published: February 2024

Collagen, the main component of the tumor microenvironment, plays a key role in the development of breast cancer (BCa); however, the specific changes in its spatial organization during tumor progression have not been definitively elucidated. The existing and available methods for assessing the morphometric parameters of the stroma's fibrous component are insufficient for a detailed description of the state of collagen fibers and for assessing its changes to evaluate the aggressiveness of the BCa course. The aim of the work was to develop an algorithm for microphoto analysis to assess the spatial organization of collagen in BCa tissue of patients with different clinical statuses. The study was conducted on 60 tissue samples of stage I‐II BCa. The processed images were analyzed using the software packages CurveAlign v4.0 and imagej. We established that the increase in BCa stage and the decrease in tumor differentiation grade are associated with decreased length, width, and straightness of collagen fibers, as well as their increased density. The formation of an aggressive basal molecular BCa subtype was accompanied by an increase in tumor‐stroma ratio. The obtained results indicate the possibility of practical application of the developed algorithm for evaluating the spatial organization of collagen in BCa tissue to predict the aggressiveness of the disease course.
Microstructure Characterization and Mechanical Properties of Polymer‐Derived (HfxTa1−x)C/SiC Ceramic Prepared upon Field‐Assisted Sintering Technique/Spark Plasma Sintering
Authors: Thor Nathalie , Winkens Georg , Bernauer Jan , Petry Nils‐Christian , Beck Katharina , Wang Jin , Schwaiger Ruth , Riedel Ralf , Kolb Ute , Lepple Maren , Pundt Astrid
Published: February 2024

The high‐temperature microstructural evolution and mechanical properties of two SiC‐based polymer‐derived ceramics with different Hf:Ta molar ratios are investigated using electron microscopy techniques and manipulated by nanoindentation. The as‐pyrolyzed ceramic powder consists of an amorphous Si(HfxTa1−x)C(N,O) structure (where x = 0.2, 0.7) with localized nanocrystalline transition metal carbides (TMCs). Subsequent application of the field‐assisted sintering technique (FAST) for high‐temperature consolidation results in a crystalline (HfxTa1−x)C/SiC ultra‐high temperature ceramic nanocomposite. The microstructure contains powder particle‐sized grains and sinter necks between the former powder particles. The powder particles consist of a β‐SiC matrix and small TMCs. Large TMCs are observed on the internal surfaces of former powder particles. This is due to the pulsed direct current and the resulting Joule heating that facilitates diffusion as well as oxygen impurities. Sinter necks of large β‐SiC grains form during the FAST process. The microstructural regions are assessed using high‐throughput nanoindentation. The hardness for SiC/(Hf0.7Ta0.3)C is measured on the formed grains and the sinter necks giving mean hardness values of about 27 and 37 GPa, respectively.
Organohydrogel‐Based Soft SEMG Electrodes for Algorithm‐Assisted Gesture Recognition
Authors: Xu Yixin , Deng Lianjun , Lu Yuyao , Zhang Jianhuan , Xu Zhouyi , Xu Kaichen , Zhang Chentao
Published: February 2024

Epidermal electronics that can monitor physiological signals such as surface electromyogram (sEMG) signals attract widespread attentions in personalized healthcare, human–machine interfaces (HMI) and virtual/augmented reality (AR/VR). However, conventional electromyographic electrodes suffer from skin discomfort, susceptibility to motion artifact interference, and short service lifetime. Here, an organohydrogel‐based sEMG electrode endows with high conductivity, low modulus and long‐term stability is developed by doping partially reduced graphene oxide (pRGO) into highly cross‐linked organohydrogel network. The as‐fabricated polyacrylamide/sodium alginate/tannic acid/partially reduced graphene oxide (PAM/SA/TA/pRGO) organohydrogel possesses farewell conductivity (4.22 S m−1) while preserving tissue‐like compliance (Young's modulus ≈32 KPa), excellent stretchability (≈600%), high adhesion as well as superior anti‐drying properties. In addition, a stretchable sEMG electrode for long‐term reliable service is fabricated via immobilizing the organohydrogel electrodes onto a flexible very high bond (VHB) substrate. As a result, the integrated electrodes show high signal‐to‐noise ratio (SNR) (35.15 db) comparable to that of the commercial electrodes. Furthermore, with assistance of deep learning, the proposed sEMG electrodes obtain high identification accuracy of 97.11% in distinguishing sophisticated gestures. This system can be further exploited for real‐time tele‐operations and offers broad prospects in human–machine immersive interactive application.
Electro‐field alignment in a novel metal–organic framework for benchmark separation of ethylene from a ternary gas mixture
Authors: Wang Lingmin , Zhang Yan , Zhang Peixin , Liu Xing , Xiong Hanting , Krishna Rajamani , Liu Junhui , Shuai Hua , Wang Pengxiang , Zhou Zhenyu , Chen Jingwen , Chen Shixia , Deng Shuguang , Wang Jun
Published: February 2024

One‐step separation of C2H4 from ternary gas mixtures containing acetylene (C2H2), ethylene (C2H4), and carbon dioxide (CO2) represents a great challenge in chemical industry. Herein, we report the electro‐field alignment in a novel anion‐pillared MOF (SIFSIX‐TEPE‐Cu) for benchmark C2H4 separation from C2H2/CO2/C2H4 gas mixtures. The semi‐cage cavities featuring capped facets generated negative potentials along anion pillars and compensatory positive‐charged electro‐fields along organic ligands (TEPE) that facilitate specific recognitions of C2H2 and CO2 over C2H4. As a result, SIFSIX‐TEPE‐Cu exhibits high adsorption capacities for C2H2 (123 cm3 g−1) and CO2 (65 cm3 g−1) at 1.0 bar and 298 K. Notably, the record‐high C2H2 uptake (78 cm3 g−1) at 0.01 bar and remarkable C2H2/C2H4 selectivity (615.2) renders benchmark trace C2H2 removal ability. Dynamic breakthrough experiments demonstrate the benchmark productivity for high‐purity C2H4 (>99.995%) of 194.7 mol kg−1 and 5.96 mol kg−1 from binary C2H2/C2H4 (1/99, v/v) and ternary C2H2/CO2/C2H4 (1/9/90, v/v/v) gas mixtures.
Zinc ion Batteries: Bridging the Gap from Academia to Industry for Grid‐Scale Energy Storage
Authors: Liu Sailin , Zhang Ruizhi , Wang Cheng , Mao Jianfeng , Chao Dongliang , Zhang Chaofeng , Zhang Shilin , Guo Zaiping
Published: February 2024

Zinc ion batteries (ZIBs) exhibit significant promise in the next generation of grid‐scale energy storage systems owing to their safety, relatively high volumetric energy density, and low production cost. Despite substantial advancements in ZIBs, a comprehensive evaluation of critical parameters impacting their practical energy density (Epractical) and calendar life is lacking. Hence, we suggest using formulation‐based study as a scientific tool to accurately calculate the cell‐level energy density and predict the cycling life of ZIBs. By combining all key battery parameters, such as the capacity ratio of negative to positive electrode (N/P), into one formula, we assess their impact on Epractical. When all parameters are optimized, we urge to achieve the theoretical capacity for a high Epractical. Furthermore, we propose a formulation that correlates the N/P and Coulombic efficiency of ZIBs for predicting their calendar life. Finally, we offer a comprehensive overview of current advancements in ZIBs, covering cathode and anode, along with practical evaluations. This Minireview outlines specific goals, suggests future research directions, and sketches prospects for designing efficient and high‐performing ZIBs. It aims at bridging the gap from academia to industry for grid‐scale energy storage.
Recombinant production of a highly efficient photolyase from Thermus thermophilus
Authors: Torres‐Obreque Karin , Gonçalves Felipe Gobbi , Ferraro Rafael Bertelli , Fuentes‐León Fabiana , Menck Carlos Frederico Martins , Costa‐Silva Tales Alexandre , Monteiro Gisele , Perego Patrizia , Rangel‐Yagui Carlota de Oliveira
Published: February 2024

Ultraviolet (UV) radiation from sunlight can damage DNA, inducing mutagenesis and eventually leading to skin cancer. Topical sunscreens are used to avoid the effect of UV irradiation, but the topical application of DNA repair enzymes, such as photolyase, can provide active photoprotection by DNA recovery. Here we produced a recombinant Thermus thermophilus photolyase expressed in Escherichia coli, evaluated the kinetic parameters of bacterial growth and the kinetics and stability of the enzyme. The maximum biomass (𝑋𝑚𝑎𝑥) of 2.0 g L−1 was reached after 5 h of cultivation, corresponding to 𝑃X = 0.4 g L−1 h. The µ𝑚𝑎𝑥 corresponded to 1.0 h−1. Photolyase was purified by affinity chromatography and high amounts of pure enzyme were obtained (3.25 mg L−1 of cultivation). Two different methods demonstrated the enzyme activity on DNA samples and very low enzyme concentrations, such as 15 µg mL−1, already resulted in 90% of CPD photodamage removal. We also determined photolyase kM of 9.5 nM, confirming the potential of the enzyme at very low concentrations, and demonstrated conservation of enzyme activity after freezing (‐20°C) and lyophilization. Therefore, we demonstrate T. thermophilus photolyase capacity of CPD damage repair and its potential as an active ingredient to be incorporated in dermatological products.
Unlocking Quercetin's Neuroprotective Potential: A Focus on Bee‐Collected Pollen
Authors: Kostić Aleksandar Ž. , Arserim‐Uçar Dılhun Keriman , Materska Małgorzata , Sawicka Barbara , Skiba Dominika , Milinčić Danijel D. , Pešić Mirjana B. , Pszczółkowski Piotr , Moradi Donya , Ziarati Parisa , Bienia Bernadetta , Barbaś Piotr , Sudagıdan Mert , Kaur Preetinder , Sharifi‐Rad Javad
Published: February 2024

In the quest to evade side effects associated with synthetic drugs, mankind is continually exploring natural sources. In recent decades, neurodegenerative disorders (NDDs) have surged dramatically compared to other human diseases. Flavonoids, naturally occurring compounds, have emerged as potential preventers of NDD development. Notably, quercetin and its derivatives demonstrated excellent antioxidant properties in the fight against NDDs. Recognizing bee‐collected pollen (BP) as a well‐established excellent source of quercetin and its derivatives, this review seeks to consolidate available data on the prevalence of this flavonoid in BP, contingent upon its botanical and geographical origins. It aims to advocate for BP as a superb natural source of “drugs” that could serve as preventative measures against NDDs. Examination of numerous published articles, detailing the phenolic profile of BP, suggests that it can be a great source of quercetin, with an average range of up to 1000 mg/kg. In addition to quercetin, 24 derivatives (with rutin being the most predominant) have been identified. Theoretical calculations, based on the recommended dietary intake for quercetin, indicate that BP can fulfil from 0.1 to over 100 % of the requirement, depending on BP's origin and bioaccessibility/bioavailability during digestion.
Fragment‐Based Design, Synthesis, and Characterization of Aminoisoindole‐Derived Furin Inhibitors
Authors: Lange Roman W. , Bloch Konstantin , Heindl Miriam Ruth , Wollenhaupt Jan , Weiss Manfred S. , Brandstetter Hans , Klebe Gerhard , Falcone Franco H. , Böttcher‐Friebertshäuser Eva , Dahms Sven O. , Steinmetzer Torsten
Published: February 2024

A 1H‐isoindol‐3‐amine was identified as suitable P1 group for the proprotein convertase furin using a crystallographic screening with a set of 20 fragments known to occupy the S1 pocket of trypsin‐like serine proteases. Its binding mode is very similar to that observed for the P1 group of benzamidine‐derived peptidic furin inhibitors suggesting an aminomethyl substitution of this fragment to obtain a couplable P1 residue for the synthesis of substrate‐analogue furin inhibitors. The obtained inhibitors possess a slightly improved picomolar inhibitory potency compared to their benzamidine‐derived analogues. The crystal structures of two inhibitors in complex with furin revealed that the new P1 group is perfectly suited for incorporation in peptidic furin inhibitors. Selected inhibitors were tested for antiviral activity against respiratory syncytial virus (RSV) and a furin‐dependent influenza A virus (SC35M/H7N7) in A549 human lung cells and demonstrated an efficient inhibition of virus activation and replication at low micromolar or even submicromolar concentrations. First results suggest that the Mas‐related G‐protein coupled receptor GPCR‐X2 could be a potential off‐target for certain benzamidine‐derived furin inhibitors.
An Indole‐based Chromofluorogenic Probe for Detection of Trivalent Al3+, Ga3+, In3+ and Fe3+ Ions
Authors: Heena  , Yadav Vikas , Saini Saakshi , Roy Partha , Layek Samar , Goswami Tapas , Kumar Sushil
Published: February 2024

An easily synthesizable indole‐derived chromofluorogenic probe InNS has been demonstrated for recognition of trivalent metal ions (i. e., Al3+, Ga3+, In3+ and Fe3+). Both UV‐Vis and emission spectral studies have been employed to assess the cation sensing ability of InNS in semi‐aqueous medium. This probe exhibited a chromogenic response for these metal ions, and the related change was accompanied with the appearance of a new absorption near 376 nm. An obvious color change from pale yellow to dark yellow could also be noticed upon addition of the aforementioned metal ions to the probe's solution. Distinctively from the UV‐Vis analysis, the fluorescence behavior of InNS was completely different; it displayed a ‘turn‐on’ fluorescence response for only Al3+ among all the studied cations. The detection limit and the association constant (Ka) for Al3+ were determined to be 12.5 nM and 6.85×106 M−1, respectively. A potential 1 : 1 binding mode of Al3+‐InNS has been established based on Job's plot, 1H NMR and DFT analyses. The reversibility experiment was conducted using strongly chelating EDTA ion, and a corresponding logic gate has been devised. In terms of practical applications, the InNS has been utilized to detect Al3+ in human breast carcinoma (MCF‐7) cell lines displaying promising ‘turn‐on’ bioimaging experiments.