A1 A2 A3 Research Articles

Preparation and study the behavior of blend (Ep+ PMAA) reinforced by SiC and B nanopartieles

Composite materials (A, A1, A2, A3) were prepared from blend (Ep95%+PMAA 5%) reinforced by silicon carbide (SiC) of a grain size less than ( 80 nm ) and boron ( B ) of grain size ( 70 nm ) with weight fraction of 20% , using the hand layup method. Composites materials of which have been prepared are: * Blend of ( Ep 95% + PMAA 5% ) is symbol A.* Blend ( Ep + PMAA ) 80% +SiC 10% +B 10% with weight fraction of 20% is symbol A1.* Blend ( Ep + PMAA ) 80%+ B 20% with weight fraction of 20% is symbol A2.** Blend ( Ep + PMAA) 80% + SiC 20% with weight fraction of 20% is symbol A3. Study involved some mechanical tests, such as Tensile, bending (3-point test), compression and hardness tests. Also some physical test, thermal conductivity and electrical conductivity (dielectric constant).as well as the effect of the environment on the behavior of the composites. The result shows that the addition of SiC and boron nanoparticles powder to the blend (Epoxy + PMAA) enchained the mechanical properties for sample A1 A2 A3 at normal condition. By comparison it was found.

An extended π-backbone for highly efficient near-infrared thermally activated delayed fluorescence with enhanced horizontal molecular orientation.

Near-infrared thermally activated delayed fluorescence (NIR-TADF) materials with emission over 700 nm have been insufficiently investigated mainly due to the limited choice of strong donor/acceptor units for molecular construction and the limited electronic coupling between the donors and acceptors. Herein, a novel D-A1-A2-A3 configuration was developed for the design of a NIR-TADF material (TPA-CN-N4-2PY), in which three types of sub-acceptor units (CN: cyano; N4: dipyrido[3,2-a:2',3'-c]phenazine; PY: pyridine) were incorporated into a molecular skeleton to reinforce the electron-accepting strength. The attachment of two pyridine units on TPA-CN-N4 produced TPA-CN-N4-2PY with an extended π-backbone, which shifted the electroluminescence (EL) emission into the NIR region and enhanced the horizontal ratio of emitting dipole orientation (Θ//) simultaneously. TPA-CN-N4-2PY-based OLEDs demonstrated a record-high external quantum efficiency (EQE) of 21.9% with an emission peak at 712 nm and Θ// = 85% at the doping ratio of 9.0 wt%. On the contrary, the parent compound TPA-CN-N4-based OLEDs at the same doping ratio achieved an EQE of 23.4% at 678 nm with Θ// = 75%. This multiple sub-acceptors approach could enrich the design strategy of the NIR-TADF materials, and the large conjugated system could improve the Θ// for achieving efficient emitters.

Correlation between functional and radiological outcome of distal femur fractures treated with minimally invasive percutaneous plate osteosynthesis locking compression plate

Aims: To prospectively study the functional outcome of extra articular and intra articular distal femur fractures treated with minimally invasive percutaneous plate osteosynthesis using modified Rasmussen criteria and correlation with radiological outcome described by Handolin et al.Materials and Methods: Total 25 patients with distal femur fractures [A1 A2 A3 B1 B2 B3] were treated in our institution. They were operated with minimally invasive percutaneous plate osteosynthesis [mippo] lcp between december 2019 to june 2021 and examined according to protocol clinically and radiologically. Followed up regularly by clinical examination, rasmussens clinical scoring and xrays taken immediately after operation, at 6weeks, 12 weeks, and 24 weeks after surgery and ct scan in 3rd to 5th postoperative day or at immediate follow up.Results: Total 25 patients were evaluated postoperatively thoroughly for functional and radiological outcome using modified Rasmussen’s criteria and criteria described by Handolin et al. which showed excellent and good results of functional outcome in 65% (16) and 35% (9) patients respectively and no poor results. Coronal and sagittal alignments were satisfactory in 92% and 96% of subjects. Rotational alignment was satisfactory in 56% of patients. According to Handolin et al. classification excellent results in 16% (4) of patients good in 40% (10) fair in 32% (8) poor in 12%(3) of subjects. Leg length discrepancy was satisfactory in 92% (23) of patients. Conclusion: Minimally invasive percutaneous plate osteosynthesis (MIPPO) showed an excellent option in treating the distal femoral fractures due to minimal soft tissue distruption. But regardless of the fracture pattern, rotational malalignment may occur at an extremely high rate after mippo for distal femoral fractures whereas satisfactory alignment is obtained for coronal and sagittal alignments and limb length.

Investigation of the effect ofpolymer‐basednovel grinding aids on cement grinding efficiency

AbstractGrinding aids, primarily amine group chemicals, are used to reduce agglomeration and increase concrete strength in order to ensure an efficient comminution process in the modern cement industry. This paper aims to investigate polymer‐based novel grinding aids on cement grinding efficiency. It is hereby conventional grinding aids such as triethanolamine, triisopropanolamine, and other polymer‐based novel chemicals are examined to reveal their effects on cement grains in grinding process. The physical, chemical, and mechanical properties of the final product in concrete were also compared to each other within the study. The experimental results showed that using polymer‐based grinding aids (A1–A2–A3) increased the fineness of the cement by up to 15%, the cement strength by up to 5% and reduced the water requirement by up to 8%. In the grinding process, the polymer‐based grinding chemicals (A1–A2–A3) also reduced agglomeration and surface energies on cement grains. Furthermore, the energy consumption was reduced by 7%–9% while the grinding performance was increased by 30%–32%. The flocculation on the mill's internal walls was also observed, resulting in a decrease in ball surface area. Finally, these results suggest that polymer‐based chemical additives may outperform conventional grinding chemicals in the cement comminution process.

Corrigenda: Universal inelastic electron scattering cross‐section including extrinsic and intrinsic excitations in XPS

Surface and Interface AnalysisVolume 52, Issue 8 p. 530-530 CORRIGENDUMFree Access Corrigenda: Universal inelastic electron scattering cross-section including extrinsic and intrinsic excitations in XPS This article corrects the following: Universal inelastic electron scattering cross-section including extrinsic and intrinsic excitations in XPS Eustache Gnacadja, Nicolas Pauly, Sven Tougaard, Volume 52Issue 7Surface and Interface Analysis pages: 413-421 First Published online: January 24, 2020 First published: 23 June 2020 https://doi.org/10.1002/sia.6858AboutSectionsPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinked InRedditWechat The authors of Gnacdja et al.1 have identified the following error in their paper. In Table 4, the values of a2 and a3 were reversed. The corrected Table 4 is provided here: B C a1 a2 a3 2192.8 1643.1 0.082 0.0695 0.8217 REFERENCE 1Gnacadja E, Pauly N, Tougaard S. Universal inelastic electron scattering cross-section including extrinsic and intrinsic excitations in XPS. Surf Interface Anal. 2020; 52(7): 413- 421. https://doi.org/10.1002/sia.6749Wiley Online LibraryCASWeb of Science®Google Scholar Volume52, Issue8August 2020Pages 530-530 ReferencesRelatedInformation

GEOLOGICAL CHARACTERISTICS OF THE REGION GEREDE (BOLU)

The study area covers an area of approximately 600km 2 in the Gerede district of the Province of Bolu, which is located in 1/25.000 scale G28 a1 a2 a3 a4 topographical sheets showing north-west of Turkey. This study tried to reveal the general geology of the study region, which is bound by the Mengen district on the north and Gerede district on the southeast. The study area includes various rocks with similar lithology and stratigraphic sequence with ages ranging from the Paleozoic to Quaternary period. Although the base complex, which constitutes the oldest, rocks of the region, cannot be observed in the mapped geographical area in Gerede, though it's known to exist at the base. The limestones developed on the tithonic facies of Late Jurassic-Early Cretaceous age on the base complex of Permo-Triassic period are incompatible. It is determined that the Upper Jurassic-Lower Cretaceous aged limestones are rich in titonic facies and rich in calpionel contents. As a result of detailed paleontological and biostratigraphic studies on the samples; 3 calpionel species and 7 species of these species, including Tintinnopsella carpathica (Murgeanui & Filipescu), Crassicollaria brevis Remane, Crassicollaria intermedia (Durand Delga), Crassicollaria parvula Remane, Crassicollaria massutiniana (Colom), Calpionella alpina Lorenz, Calpionella elliptica Cadisch. It was determined in the study area, the lower levels of Upper Cretaceous are composed of sandstone-shale-marl intercalated flysch and clayey limestones containing agglomerate intercalations and the Maastrichtian level are composed of rocks and felsic intrusive rocks in the volcano-flysch facies. Among Maestrichtian age-giving units; Globotruncana arca Cushman, Globotruncanita conica White, Rosita contusa (Cushman) and Globotruncana sp. planktonic foraminifera were detected. Considering the relationship between the rocks in the region, the presence of a gradual transgression along the Mesozoic is noteworthy. It is composed of Tertiary, Paleocene aged sandstone shales, agglomerate, Lutetian, Miocene and Neogene aged terrestrial formations with volcanic activities, occurred in a marine environment and particularly observed in the western part.

Effect of selected “desirable difficulty” learning strategies on the retention of physiology information

The purpose of this study was to examine the effects of interleaving and expanding retrieval on the retention of physiology concepts. Participants (n = 189) read and then reread 30 immunology and reproductive physiology passages. Half of the participants read and then reread the passages in a blocked manner (e.g., a(1)a(2)a(3)b(1)b(2)b(3)), and the other half did so in an interleaved manner (e.g., a(1)b(1)b(2)a(2)a(3)b(3)). Participants were then repeatedly assessed, without feedback, after either a uniform or an expanding series of intervals. Half of the students from both the blocked and interleaved groups completed the assessments 1, 2, and 3 days after rereading the passages (uniform), whereas the other half completed the assessments immediately and 1 and 3 days after rereading the passages (expanding). All participants completed a final assessment 10 days after rereading the passages. There were no significant differences between the blocked and interleaved groups on any of the assessments, nor were there any significant interactions between the groups on any of the assessments. Those in the expanding retrieval group scored significantly higher than those in the uniform group on all four assessments (ANOVA; assessment 1: F = 35.12, P = 0.00; assessment 2: F = 13.88, P = 0.00; assessment 3: F = 10.87, P = 0.00; and assessment 4: F = 6.79, P = 0.01). Mean final assessment scores were 47.58 ± 19.81 and 40.50 ± 17.17 for the expanding and uniform groups, respectively. The results indicate that participants benefited more from expanding retrieval practice.

Zur Beziehung zwischen Verbund Qualität und Impact-Echo Frequenzspektrum / On the Relation between Bond Quality and Impact-echo Frequency Spectrum

According to EN 1504-10 and ACI Concrete Repair Manual, bond strength and interface quality are the main features of repair system necessary to be assessed. Pull-off test is most commonly used for bond strength evaluation but growing interest in nondestructive techniques (NDT) is recently noted. Impact-echo (IE) is treated as the most promising one for this purpose. The aim of this paper is to analyze an effect of bond quality on stress wave propagation in repair systems. A group of samples has been prepared in order to obtain repair systems of different bond quality. Prior to repair, quality of concrete substrates has been characterized according different techniques: compressive strength, superficial cohesion, surface roughness index and cracking quantification. Than a polymer-modified repair mortar has been applied. After hardening, IE signals have been recorded and pull-off bond strength determined. The relationships between parameters characterizing surface quality, bond strength, IE frequency spectrum and results of wavelet analysis of IE signal have been analyzed. 2 ICPIC 2010 – 13 International Congress on Polymers in Concrete Table 1: Characteristic of tested repair systems Group A Group B Concrete substrate C30 C40 C45 C25 C35 C50 Compressive strength classes C30/37 C40/50 C45/55 C25/30 C35/45 C50/60 Surface preparation PL, SB-D, JH, HD NT, SB-W, SC, LC Sample dimensions 80x60x10 cm 50x50x7cm Repair material PCC (A), Dmax = 2,0mm PCC (B), Dmax = 0,25mm Repair layer thickness 3cm 3cm 2.2 Results of substrate characteristics The quality of substrates was characterized from point of view of their roughness, microcracking and surface tensile strength. The roughness was measured by sand patch test according to EN 1766 resulting Surface Rough Index SRI (Fig.1a). Substrates of Group A can be ranked from polished smooth surface (PL), by dry sandblasted (SB-D) and jack hammered (JH) to very irregular hydrodemolitioned one (HD). In Group B low-pressure waterjetting (LC) has no big influence on profile in comparison to brushed surface (NT), while wet sandblasting (SB-W) and scarification (SC) increase roughness a little. Microcracking of samples of Group A was observed on the cross-section of the 8 cm cores on the near-to-surface layer in the area of 2 cm depth. Density of microcracks was calculated (Fig.1b). It can be concluded, that more aggressive surface preparation technique influence more on microcracking: it was observed two times higher density of microcracks after jack hammering (JH) and hydrodemolition (HD) than after dry sandblasting (SB-D) and polishing (PL). As the aggressiveness of surface treatment of samples of Group B was small, the microcracking was not observed here, although it can be expected a little higher level for scarification. a) 0.0 1.0 2.0 3.0 4.0 5.0 P L SB -D JH H D L C N T SB -W S C surface treatment SR I [m m ] Group A Group B b) Group A 0.00 0.01 0.02 0.03 0.04 0.05 P L SB -D JH H D surface treatment L A [ m m /m m 2 ] Figure 1: Surface Roughness Index, SRI (a) and density of microcracks, LA (b) depending on the method of surface treatment The pull-off test according EN 1542 and ASTM C 1583 04 commonly used for evaluation of bond strength (Fig.2b) was applied for surface tensile strength (fhs) measurement (Fig.2a) including type of failure registration. In case of samples of Group A the concrete quality did not have a major influence on the surface tensile strength after surface treatment as it was for samples of Group B (Fig.3). It can be also observed (Fig.4) that for surfaces jack hammered (Group A) and scarified (Group B), more that 50 % of failures appeared near in the superficial zone (type A1, see Fig.2a). It is probably due to microcracking already mentioned. a) b) A A /B B 15 mm repair material concrete substrate Figure 2: Pull-off for evaluation of surface tensile strength (a) and bond strength (b) A1 A2 A3 15 mm T. Piotrowski, A. Garbacz, A. van der Wiellen, L. Courard, F. Nguyen 3

Clearance mechanisms of von Willebrand factor and factor VIII.

Clearance mechanisms of von Willebrand factor and factor VIII.

Factor VIIIa Decay Due to A2 Subunit Dissociation Is Regulated by the A1 Domain.

FVIII contains three homologous A domains, two homologous C domains and a single B domain. The B domain and an activation peptide between the B and A3 domains are released during the activation of fVIII by thrombin. The resulting fVIIIa molecule has a heterotrimeric A1/A2/A3-C1–C2 subunit structure. FVIIIa is unstable at physiological concentrations and pH due to dissociation of the A2 subunit from the A1/A3-C1–C2 dimer, which is three-fold faster in human fVIIIa than porcine fVIIIa. Fine regulation of fVIII activity appears to be important because plasma fVIII levels are positively correlated with a risk of arterial and/or venous thrombosis. Additionally, mutations in the fVIII gene have been identified that result in fast A2 dissociation and a hemophilia phenotype. To characterize structural determinants involved in A2 subunit dissociation, we constructed and purified recombinant human, porcine and hybrid human/porcine fVIII molecules corresponding to all eight combinations of human and porcine fVIII A1–A2–A3 domains (HHH, HHP, HPH, HPP, PHH, PHP, PPH and PPP). All of the constructs contained the human C1 and C2 domains. The rate of A2 subunit dissociation was studied at pH 7.4 by measuring decay of fVIIIa activity in an assay system using purified intrinsic fXase components and displayed first-order kinetics in all cases. Constructs containing the porcine A1 domain behaved similarly to porcine fVIIIa (Table 1). In contrast, constructs containing the human A1 domain behaved similarly to human fVIII, except for the HPH construct, which displayed intermediate behavior.Table 1A domain hybrid fVIIIIa decay ratesConstructk (min− 1)aHHP0.317 ± 0.018HHH (human)0.275 ± 0.013HPP0.262 ± 0.011HPH0.193 ± 0.012PPH0.128 ± 0.005PHP0.118 ± 0.003PPP (porcine)0.109 ± 0.003PHH0.105 ± 0.002a mean and estimated s.d. from nonlinear least-squares analysisThe fVIII A domains contain two azurin-like subdomains. Additionally, the A1 domain contains a COOH-terminal 37 amino acid acidic region. To further characterize the involvement of the A1 domain in fVIIIa decay, we prepared constructs that contained the combinations hhp, phh, pph, hpp or hph of the three A1 subdomains in an otherwise human background. Comparison of their fVIIIa decay rates indicated that the acidic region is not involved in A2 dissociation (Table 2, cf. hhp versus pph). Substitution of either azurin-like porcine subdomain produced relatively stable fVIIIa molecules.Table 1A1 subdomain hybrid fVIIIIa decay ratesConstructk (min− 1)ahhp0.263 ± 0.012phh0.167 ± 0.005pph0.157 ± 0.008hpp0.133 ± 0.005hph0.134 ± 0.010a mean and estimated s.d. from nonlinear least-squares analysisThese results indicate that porcine-specific amino acid side chains in both azurin-like A1 subdomains are responsible for differential fVIIIa decay rates. A1 domain mutations may represent adaptations to differences in hemostatic requirements between species.

Atrioventricular nodal reentry tachycardia with multiple AH jumps: electrophysiological characteristics and radiofrequency ablation.

This article describes the additional use of incremental atrial burst pacing (A1A1) and double atrial extrastimulation with a predefined fast pathway conducted A2 (A1A2A3), rather than single atrial extrastimulation (A1A2) only, to characterize typical atrioventricular nodal reentrant tachycardia (AVNRT). The authors noted an additional 32% of patients had multiple anterograde AV nodal physiology demonstrated when A1A1 or A1A2A3 protocols were deployed compared to more conventional A1A2 protocols. The A2H2max (449 +/- 147 vs 339 +/- 94 ms) and A3H3max (481 +/- 120 vs 389 +/- 85 ms) were higher in 31 patients where multiple jumps in the AV nodal conduction curve were obtained (group 1) compared to 192 patients where only single jump was obtained (group 2) (both P < 0.01). Postablation, the degree of reduction of A2H2max (49%) and A3H3max (50%) in group 1 was greater than in group 2 (38% and 42%, respectively, P < 0.05). In seven of group 1 patients in whom A1A2A3 stimulation was required to reveal multiple jumps, the A2H2max remained unchanged after ablation (237 +/- 89 vs 214 +/- 59, P > 0.05). A3H3max was the only parameter that shortened significantly after ablation. Generally, successful ablation resulted in loss of multiple discontinuities in A1A1/A1H1 or A2A3/A3H3 curves. In conclusion, a combination of A1A2, A1A1, and A1A2A3 are required to fully elucidate AVNRT. Significant shortening of AHmax or loss of multiple jumps after ablation indicates successful elimination of AVNRT in these patients.

蛭子井氏の定理と (15&lt;SUB&gt;4&lt;/SUB&gt;, 20&lt;SUB&gt;3&lt;/SUB&gt;) コンフィグレイション

A simple geometric proof of Ebisui's theorem, if two triangles A1A2A3 and B1B2B3 are perspective and C3 = A1B2∩A2B1, C1=A2B3∩A3B2, C2=A3B1∩A1B3 then A1A2 A3 and C1C2C3 are also perspective, is given, which is using Desargues's theorem and its converse. With the theorem and an additional theorem, a (154, 203) configuration can be constructed, which is transitive both on points and lines.

Identities on Point-Line Figures in the Euclidean Plane

Introduction In [3] Larry Hoehn gave a proof of a theorem that is known as the Theorem of Pratt-Kasapi [1]. This note collects some ideas on how to generalize the theorem so that it holds not only for the pentagram but also for many other figures of the Euclidean plane and their duals. THEOREM 1. In a pentagrarn A1 A2 A3 A4 A5 with B1, B2, B3, B4, B5 as the points of intersection of its sides (FIGURE 1), the Pratt identity holds:

Contribuição para o estudo de tabelas de classificação

O presente trabalho estabelece um método geral para se construir tabela de classificação de grãos ou outros produtos por tipo, isto é, baseado no número de defeitos contidos numa determinada amostra de produto. A teoria é formulada impondo-se a condição de que as amostras devem representar com igual precisão os tipos. É apresentada uma fórmula matemática que permite construir uma escala de classificação por tipos, partindo-se de um único ponto da escala, isto é, de um tipo cujo número de defeitos é escolhido a priori. A fórmula permite construir escalas com a precisão que se queira. Na aplicação prática, as escalas construídas matemàticamente de acôrdo com êste trabalho, devem satisfazer à condição de que os tipos estabelecidos devem ser fàcilmente diferenciáveis. O trabalho dá um exemplo de aplicação no estudo das tabelas de classíficação, por tipo, do café beneficiado.

A Criterion for the Reality of Cyclic Variations

IN investigations of natural phenomena the question may arise whether cyclic variations which appear in a series of s experimental (or observational) quantities a1 a2 a3... a8 are real or not. Let k be the number of extrema in this series, where by extremum is meant such a quantity am which is. either greater or smaller than both its neighbours, am–1 and am+1. If in the above series long sequences of increasing values alternate with long sequences of decreasing values (that is, if k is very small in comparison with s), the existence of cyclic variations is obvious, and no criterion for their reality is needed. But if these sequences are not very long, such a criterion may be useful; for it seems possible that in a series of quantities distributed at random short sequences of increasing or decreasing values will be found.

Geometrical Interpretation of a few concomitants of the cubic in the Argand Plane

be the binary cubic whose coefficients a1, are complex numbers represented on the Argand Plane. Then if its roots are z1, z2, z3, the three corresponding points form the vertices of a triangle A1 A2 A3. Let this triad of points be said to represent the cubic. Then its Hessianis represented by a certain pair of other points; likewise every first polarassociates a definite pair of points (z) with any given point (y).