Μm Thickness Research Articles

Enhancing Anti-Blast Capabilities of Pipelines with High-Performance Composite CFRP Laminate: Computational Fluid Dynamics-Based Predictive Analysis

Abstract Recent explosions highlighted the need for a thorough investigation to understand the impact of these explosions on critical infrastructural systems and networks like pipelines. This paper provides an essential understanding for developing safety protocols and interventions, strengthening resilience, enhancing public safety, mitigating socio-economic consequences, and ensuring sustained progress. Shallow buried conduits, crucial for transporting water, oil, and gas over long distances, face explosion risks due to conflicts, sabotage, terrorism, corrosion, and accidental damage. Recent blast incidents in San Francisco and Lagos underscore the devastating effects of conduit malfunctions, necessitating rigorous safety measures and technological innovations. In this research, an empty pipeline measuring 26.20 mm in thickness and subjected to a detonation initiated upon its uppermost surface is emulated, utilising the sophisticated computational capabilities of Abaqus software, integrating principles of computational fluid dynamics. Following a meticulous validation process achieved via mesh refinement analysis, the study expands to scrutinise two additional detonation scenarios — positioned above and below the pipe’s surface — while adhering to a steadfast standoff distance of 25mm. The primary objective of this scholarly endeavour is to ameliorate the deleterious repercussions inflicted upon the conduit by explosive forces, envisioning a scenario where deformation occurs without immediate rupture. To this end, a 0.15 mm thick and 200mm wide laminate composed of composite CFRP with 0°/90° fibre orientation is strategically affixed onto the upper half segment of each pipe model at the impacted region, serving as a fortification measure aimed at bolstering areas of susceptibility and potentially diminishing the magnitude of ensuing blast-induced impairment. Comparative analysis of the pipe’s performance, both with and without the applied laminate, is meticulously conducted to discern the effectiveness of this intervention. The results demonstrate a significant reduction in plastic damage with the utilisation of laminate, with models integrating CFRP experiencing an average decrease of approximately 39.94% compared to those without it. It highlights the efficacy of CFRP in protecting pipeline structural integrity against blast events.

Histological and morphometrical evaluation of the urethral wall after bioresorbable stent implantation in male New Zealand White Rabbits: A preliminary study.

The aim of the study was the histological and morphometrical evaluation of the urethral wall at three time points after bioresorbable stent implantation in male New Zealand White Rabbits. The research was performed on 26 male New Zealand White rabbits aged 3-4 months and weighing 2.1-3.0 kg. Two models of bioresorbable sodium alginate-based stents were developed and implanted into the urethral lumen for one (T1), three (T3), and six weeks (T6). Sections of 5 µm thickness were cut from the urethra at intervals of 2 mm. The sliced sections were stained with hematoxylin-eosin (H&E), Van Gieson's (VG), Von Kossa, and Movat-Russell modified pentachrome (MOVAT) staining methods. The study provided valuable information for future models of urethral stents. The first model of the stent failed to fit the requirements due to inadequate mechanical properties. It curled up on itself losing the ability to adhere to the animals' urethra and was bioresorbed three weeks after implantation. The more rigid no. 2 stent was effective in widening the urethral lumen but did not biodegrade during the experiment. A comprehensive assessment of the second model's properties of biosorption and biointegration requires an extended observation of at least 12 months for an in depth morphological analysis. Stent migration is not likely to be caused solely by the mechanical properties of the urethra or urinary flow but mainly by muscle contraction of the organ wall.

Solar spectral response of photochromic YHO films

Photochromic yttrium oxyhydride, YHO, has excellent properties as a responsive solar control material, in particular due to its color-neutral darkening. In this work, we have investigated YHO’s spectral response to the solar AM 1.5 spectrum to evaluate how the total photon activation flux changes as a function of thickness and wavelength. The calculations are based on ellipsometry measurements in the 240–2000 nm range. Our results show that the UV light absorption saturates at around 400 nm thick film, while blue light (>400 nm) continues to provide photoactivation well beyond 1 μm thickness. Understanding the spectral response and absorption per unit time of activating photons as a function of material thickness is important for evaluating the material or coating for applications.

Coercivity mechanism and magnetization reversal of anisotropic La-Nd-Dy-Fe-B micron-sized films

The coercivity mechanism and magnetization reversal process of anisotropic La-Nd-Dy-Fe-B micron-sized films have been investigated. By varying the thickness of the single-layer film from 500 nm to 6 μm, the highest coercivity of 1.88 T in the film with 3 μm thickness is achieved at 300 K, due to the large dipole interaction and domain pinning effect. When the thickness is further increased to 6um, the coercivity decreases sharply to 1.11T due to the microstructure and phase formation in the film. In the 6 μm multilayer film, the addition of a Ta spacer layer further enhances perpendicular magnetic anisotropy, the dipole interaction, and adjusts the phase distribution, collectively boosting the coercivity of the micron-sized film (1.63 T). As thickness of the film increases, the dominant mechanism of coercivity shifts from a pinning mechanism to a nucleation mechanism. This study contributes to the understanding of the coercivity mechanism and magnetization reversal process in La-Nd-Dy-Fe-B permanent magnet micron-sized films.

Renewable Nanocellulose/rGO film with a dense brick-and-mortar structure for electromagnetic interference and energy storage

Considering the high requirements for robust and flexible power supplies, the green and sustainable fiber-based supercapacitor is suitable to accommodate the inevitable serious deformation and low radiation issues in wearable electronic energy storage devices due to its easy integration. Compatible natural nanocellulose (NFC) as a framework and the two-dimensional conductive graphene (GO) nanosheets constructed a dense brick-and-mortar structure, which the dispersing effect of NFC avoided GO aggregation. The utilization of the green-reducing agent and the obtained NFC/reduced graphene oxide (rGO) composite film endowed the composite film with a continuous conductive network by the self-assembly behavior of NFC and GO, that the lightweight flexible electrode NFC/50rGO with 13 μm thickness had high conductivity (883.70 S m−1), a total electromagnetic shielding efficiency of 27.1 dB at 8.2 GHz frequency, electrochemical behavior (mass-specific capacitance up to 170.6F g−1), and reversible charge–discharge behavior. Developing a green and portable small electronic device with such a flexible and high-strength electrode symbolizes the critical development direction in the future electronic equipment field.

ИССЛЕДОВАНИЕ ВЛИЯНИЯ ПОСТТЕРМООБРАБОТКИ НА СТРУКТУРУ АЛИТИРОВАННОГО СЛОЯ НА ТИТАНЕ ВТ1-0

The study results of the post-heat treatment effect on the structure of the aluminized layer on VT1-0 titanium are presented. It is shown that the coating after heat treatment at 700 and 850 °C for 20 h consists of two layers. In the outer layer, rounded TiAl3 particles are separated by aluminum oxide Al2O3. A continuous diffusion zone of ~10 μm thickness is formed at the boundary with titanium, consisting of several layers representing TiAl2, TiAl and Ti3Al aluminides.

Hard antireflection coatings with enhanced mechanical properties based on gradient structure

Antireflection (AR) coatings with sapphire-like hardness are highly desired in various applications. Traditionally, hard AR coatings resist penetration, scratching, and abrasion by depositing a hard layer, such as silicon nitride (Si3N4), with a 1 to 2 µm thickness. However, thick Si3N4 thin films, fabricated by high-energy inductively coupled plasma assisted (ICP-assisted) sputtering, often introduce high residual stress, leading to severe buckling problems when the surface is scratched. To address these challenges, we employ a "Step up-step down" design method, integrating a hardness gradient structure with a series of SiOxNy films. This approach achieves high optical transmittance (Tave > 98.7 % at 420–720 nm), low residual stress (∼680 MPa), improved scratch resistance, and strong adhesion at the film-substrate interface (LC3 ∼180 mN). Our findings demonstrate significant potential for various mechanical and optical applications, including automotive and consumer electronics devices.

A comparative characterization analysis of electrode materials for optimal deposition on copper by advancing electrical discharge coating

This research explores the efficiency of Electrical Discharge Coating (EDC) as an advanced surface modification technique using powder suspension, conventional electrodes, and 3D printed electrodes (3DPE), focusing on Ti6Al4V alloys. Conventional Ti electrodes resulted in 100% titanium content with a thickness of 110 µm, while the powder suspension coating was inadequate. The use of 3D printed electrodes showed promising results, with uniform deposition of 61.20 µm thickness and enhanced surface properties under 10 A current. Further analysis of 3D printed Ti6Al4V EDC revealed a higher Ti percentage of 44.20%, TiC formation of 84.17%, and enhanced microhardness with lower surface roughness. Thorough optimization of 3D printed electrode EDC has been undertaken. The study suggests the potential replacement of traditional electrodes such as powder metallurgy with 3D printed counterparts, advancing surface modification techniques and opening new avenues for materials engineering and manufacturing processes.

Surface morphology evolution, microstructural response and mechanical property variation of Au-ion irradiated CrNbZrMoV, TiCrZrMoV, TiNbCrMoV, TiNbZrCrV and TiNbZrMoCr high-entropy alloy coatings

In this work, the CrNbZrMoV, TiCrZrMoV, TiNbCrMoV, TiNbZrCrV and TiNbZrMoCr refractory high-entropy alloy (RHEA) coatings (1.67∼2.77 μm of thickness) were prepared by magnetron sputtering. Then, 6 MeV Au-ion irradiations with 2.5 × 1015 to 1.0 × 1016 ions/cm2 fluences were performed on these coatings at 473 K, and the surface morphology, microstructure and mechanical property were investigated. The peak damage of the CrNbZrMoV, TiCrZrMoV, TiNbCrMoV, TiNbZrCrV and TiNbZrMoCr coatings under 1.0 × 1016 ions/cm2 fluence are 48, 48, 44, 48 and 48 dpa, respectively. The peak Au concentration of the CrNbZrMoV, TiCrZrMoV, TiNbCrMoV, TiNbZrCrV and TiNbZrMoCr coatings under 1.0 × 1016 ions/cm2 fluence are 4.27 × 103, 4.12 × 103, 4.13 × 103, 4.16 × 103 and 4.37 × 103 appm, respectively. The surface morphology of the CrNbZrMoV, TiCrZrMoV, TiNbZrCrV and TiNbZrMoCr coatings were smoothed obviously. For BCC TiNbCrMoV coating, irradiation caused the growth of the nanocrystalline. For amorphous coatings, the crystallization occurred in the CrNbZrMoV, TiCrZrMoV and TiNbZrMoCr coatings after 2.5 × 1015 fluence irradiation (≥12 dpa), while the TiNbZrCrV coating remain mainly amorphous structure after all irradiation. It was found that irradiation induced continuous crystallization occurred not only at the surface but also in the peak damage zone of the coating, and then grew inside the irradiated region. Apparent irradiation hardening was observed in all the coatings except the TiNbZrCrV coating. The structural stability of these coatings under the current irradiation condition was discussed. Preliminary study shows that the great irradiation tolerance of amorphous TiNbZrCrV coating may be related to the lowest electronegativity difference (Δχ = 0.121) and large atomic size difference (δ = 9.042 %) that stabilize the structure and inhibit atomic diffusion, respectively. These findings provide the guidance for the development of high irradiation tolerance materials for future nuclear energy applications with great structural stability.

A Comparison of the Shear Bond Strength between a Luting Composite Resin and Both Machinable and Printable Ceramic–Glass Polymer Materials

This study aims to compare the shear bond strength (SBS) and Weibull characteristics between a luting composite resin and both printable and two different machinable ceramic–glass polymer materials. A total of 36 substrates were prepared, with 12 in each group. Printable substrates (12 mm × 12 mm × 2 mm) were printed by using permanent crown resin (3D-PR). Machinable substrates were obtained from Cerasmart 270 (CS) and Vita Enamic (VE) blocks (2 mm in thickness). The bonding surfaces of substrates were polished and airborne abraded (50 µm Al2O3). A self-adhesive luting composite resin (RelyX U200, 3M ESPE, St. Paul, MN, USA, SLC) was applied on substrates with the help of a cylindrical (Ø3 × 3 mm) mold. The SBS test was conducted using a universal test machine. The SBSs of three materials were compared using a one-way analysis of variance (ANOVA) (α = 0.05). The Weibull modulus was calculated for each material. The Kruskal–Wallis and chi-square tests were carried out for the failure mode analysis. There was no significant difference between the SBSs of the three materials (p = 0.129). The Weibull modulus was 3.76 for the 3D-PR, 4.22 for the CS, and 6.52 for the VE group. Statistical analysis showed no significant difference between the failure modes of the groups (p = 0.986). Mixed-failure fractures were predominantly observed in all three groups. The results show that the SBS of the SLC to printable 3D-PR is comparable to that of CS and VE material. Failure modes of printable 3D-PR show similar results with two different machinable ceramic–glass polymers.

Achieving excellent properties of laser tailor-welded thin Al-Si coated press-hardened steel joint via controlling dilution rate

In laser tailor welded traditional 25 μm thick Al-Si coated press-hardened steel (PHS), a lot of ferrite was easily formed in the weld, so filling with expensive high-alloys wire is usually necessary. In this work, a new thin Al-Si coated PHS with 18 μm thickness was laser tailor welded, and a cheap low alloy wire was attempted to fill into the weld to via control the dilution rate. At a high dilution rate of 94%, the weld contained a ferrite fraction of 38%, resulting in the fracture occurring in the weld during tension and bending. At a medium dilution rate of 85%, the ferrite fraction in the weld decreased to 18%, obtaining excellent tensile and bending properties. The tensile strength and elongation of the joint reached 1528 MPa and 5.6%, respectively, with fracture being in the base metal (BM). The maximum bending load and displacement were 1291 N and 7.0 mm, respectively, and cracks initiated and propagated in the BM. This is attributed to the small amount of ferrite and stress concentration in the narrow weld. At a low dilution rate of 76%, the ferrite reduced to 6%, and the bending cracks initiated and propagated in the BM. However, the tensile specimen fractured in the weld, which should be related to the relatively low C concentration and the stress concentration at the weld toe due to the weld reinforcements.

SUB-6 5G NETWORKS: DESIGN OF BUTTON MUSHROOM MIMO ANTENNA AND IT’S INVESTIGATION

The unlicensed National Information Infrastructure radio band (n77, n78, and n46) is taken into consideration for this research work's "Multiple-input-multiple-output (MIMO)" antenna with dual band features. Gradually, the form design of simple single-patch MIMO antennas gives way to four-element MIMO antennas. Four microstrip antennas are integrated using button-like circular caps on the main patches. Reduced ground is also used in the construction of many band characteristics. Excellent isolation can be achieved by using Rectangular Metallic Strip (RMS). The suggested MIMO antenna has the advantage of covering two significant frequency bands. At 3.07 GHz and 6.31 GHz, the antenna system resonates with a total bandwidth of 2.43 GHz. The antenna design uses a FR4 substrate measuring 35 mm by 49 mm by 1.6 mm in thickness. For simulation purposes, Teflon and a specially made SMA connector with a perfect electrical conductor (PEC) are used to enhance impedance matching. An 8.2 mm feed line with an inset feed is also utilized. Research and investigation are conducted on radiation properties, including mean effective gain, envelope correction coefficient, reflection coefficient, and more. Both the reflection and isolation coefficients have values of less than -10 dB, with the former being less than -15 dB. It is a 16.30 dB increase overall. 5G applications will greatly benefit from having this smaller, four-element MIMO antenna.

Deconvolving organogenesis in space and time via spatial transcriptomics in thick tissues.

Organ development is guided by a space-time landscape that constraints cell behavior. This landscape is challenging to characterize for the hair follicle - the most abundant mini organ - due to its complex microscopic structure and asynchronous development. We developed 3DEEP, a tissue clearing and spatial transcriptomic strategy for characterizing tissue blocks up to 400 µm in thickness. We captured 371 hair follicles at different stages of organogenesis in 1 mm 3 of skin of a 12-hour-old mouse with 6 million transcripts from 81 genes. From this single time point, we deconvoluted follicles by age based on whole-organ molecular pseudotimes to animate a stop-motion 3D atlas of follicle development along its trajectory. We defined molecular stages for hair follicle organogenesis and characterized the order of emergence for its structures, differential signaling dynamics at its top and bottom, morphogen shifts preceding and accompanying structural changes, and series of structural changes leading to the formation of its canal and opening. We further found that hair follicle stem cells and their niche are established and stratified early in organogenesis, before the formation of the hair bulb. Overall, this work demonstrates the power of increased depth of spatial transcriptomics to provide a four-dimensional analysis of organogenesis.

SUB-6 5G NETWORKS: DESIGN OF BUTTON MUSHROOM MIMO ANTENNA AND IT’S INVESTIGATION

The unlicensed National Information Infrastructure radio band (n77, n78, and n46) is taken into consideration for this research work's "Multiple-input-multiple-output (MIMO)" antenna with dual band features. Gradually, the form design of simple single-patch MIMO antennas gives way to four-element MIMO antennas. Four microstrip antennas are integrated using button-like circular caps on the main patches. Reduced ground is also used in the construction of many band characteristics. Excellent isolation can be achieved by using Rectangular Metallic Strip (RMS). The suggested MIMO antenna has the advantage of covering two significant frequency bands. At 3.07 GHz and 6.31 GHz, the antenna system resonates with a total bandwidth of 2.43 GHz. The antenna design uses a FR4 substrate measuring 35 mm by 49 mm by 1.6 mm in thickness. For simulation purposes, Teflon and a specially made SMA connector with a perfect electrical conductor (PEC) are used to enhance impedance matching. An 8.2 mm feed line with an inset feed is also utilized. Research and investigation are conducted on radiation properties, including mean effective gain, envelope correction coefficient, reflection coefficient, and more. Both the reflection and isolation coefficients have values of less than -10 dB, with the former being less than -15 dB. It is a 16.30 dB increase overall. 5G applications will greatly benefit from having this smaller, four-element MIMO antenna.

Rolling contact fatigue property of gradient rare earth addition M50 bearing steel with surface nano-grains and its inhibited martensite decay

A gradient nanostructured surface layer of ∼600 μm in thickness was prepared on M50 steel with rare earth additions by a surface mechanical rolling treatment. The initial microstructure was refined into nanosized grains (∼29 nm in diameter) in the top surface layer, causing a significant increase of surface hardness. Meanwhile, the grain size increases, and the microhardness decreases gradually to the matrix values with increasing depth. Rolling contact fatigue tests showed that the fatigue lives are significantly increased by the gradient nanostructured surface layer. Analysis of failure mechanism revealed that both softening in the near surface layer and hardening in the subsurface occur under rolling contact testing. And surface spalling is the predominant failure mode, of which the cracks initiate from primary carbides in the top surface layer owing to surface softening. In gradient nanostructured samples, the nano-grains inhibit carbon migration by impeding dislocation movement in the near surface layer, so that martensite decay is suppressed. Consequently, the crack initiation is inhibited, and the fatigue property is enhanced.

Design and Fabrication of Motorized Paint Spatula Scraper

In light of the increasing demand for construction globally, this study emphasizes the importance of painters' well-being in achieving structural aesthetics. The goal of the study is to enhance the ergonomic design of the widely used Paint Spatula Scraper, promoting comfort and productivity for painters. Currently, painters still rely on manually operated tools, which can cause strain on their hands and neck from constant use. Recognizing this challenge, we aim to improve the painter's experience by replacing the conventional paint spatula scraper with a state-of-the-art Slider Crank Mechanism integrated into a DC motor. The basic idea of this innovative design is to use a DC motor, which guarantees longevity, low maintenance, and efficiency. The paint spatula scraper's functionality is improved by the sophisticated mechanism known as the Slider Crank Mechanism, which is integrated with this motor and scraper is made of premium stainless steel, its durability and corrosion resistance are guaranteed. The blade, with dimensions of 200 mm in width and 0.5mm in thickness, guarantees excellent performance while maintaining a lightweight profile for ease of use. This cutting-edge instrument promises painters a future where their work becomes more enjoyable, sustainable.

Plasmonic effect of gold nanoparticles on rear side of flexible black silicon wafer fabricated by aluminum-assisted chemical etching

In this work, we investigate the effects of the different sizes of gold (Au) plasmonic nanoparticles (NPs) on the rear surface of flexible black silicon (b-Si) wafer. The flexible b-Si (65 μm thickness) is fabricated by aluminum-assisted chemical etching (AACE) process, utilizing aluminum (Al) as the catalyst. After the b-Si fabrication, nanopores are produced on the flexible wafer surface. Then, gold nanoparticles (Au NPs) are spin-coated on the rear side of the flexible b-Si, followed by surface morphological and optical characterizations. The Au NPs with sizes of 24–92 nm have been deposited on the rear surface of the b-Si wafer. Based on the optical characterization, light absorbance increases above wavelength 800 nm due to enhanced light scattering by the Au NPs at the back surface. The average reflectance (Rave) is calculated in the 300 nm–1100 nm wavelength range for flexible crystalline silicon (c-Si) reference and compared with flexible b-Si surface and flexible b-Si/Au NPs. The lowest Rave of 15.4% is achieved for Au NPs with average size of 92 nm.

3D printed microcrystalline CsI:Tl composite scintillating thin films for X-ray imaging

The utilization of additive manufacturing techniques, especially Digital Light Printing (DLP), in fabricating CsI:Tl scintillator films demonstrates considerable potential for streamlining the production of scintillators tailored for X-ray imaging applications. This research focuses on the fabrication of CsI:Tl-based composite plastic scintillator thin films. In this study, circular films measuring 1-inch in diameter and 0.1 mm & 0.2 mm in thickness are being produced and tested for gamma photon counts under alpha and gamma radiation. To establish the stopping power range of the films, a Monte Carlo based GEANT4 simulation has been carried out. Additionally, investigations into their suitability for X-ray imaging applications are being conducted, revealing the spatial resolution of the films (0.2 and 0.1 mm) between 100 and 130 μm and 1.26 lp/mm with a contrast range of 4.0–12.3 %. The observed decrease in spatial resolution and contrast for the 0.2 mm thick film is attributed to the thickness increase exacerbating the scattering phenomenon while simultaneously enhancing the X-ray stopping power. This highlights the significance of inherent trade-off between maximizing spatial resolution and compromising light yield of 0.1 mm films compared to the 0.2 mm thick film. By utilizing 3D printing, this approach offers a cost-effective and time-efficient method for producing thin-film scintillators with enhanced flexibility and customization options compared to conventional methods.

Wear-Resistant Boronizing for 17-4PH Components of Fluid Pump

The fluid pump was the key component of the formation tester; the pump cylinder, piston, and piston rod of the fluid pump often suffer from wear scratches and seal failure, which greatly reduces the service reliability of the instrument. To improve the wear resistance of the fluid pump, 17-4PH steel specimens were treated by boronizing at 750 °C for 20 h. Specimens with and without boronizing were studied by OM, SEM, XRD, microhardness test, and wear resistance test. Layers of about 60 μm thickness formed during boronization contain a mixture of FeB, CrB, and α(B)-Fe phases, which leads to a significant improvement in microhardness (from 336 to 980 HV) and wear rate (from 16.4 × 10−5 mm3/Nm to 3.3 × 10−5 mm3/Nm). The pump cylinder and the fluid-pump piston rod were boronized and assembled into the pumping module, which passed the indoor durability test for 90 h and did not show obvious surface wear after 60 h of field experience. For the first time, the boronization process extends the service time of the fluid pump, improving the wear resistance of the pump cylinder and piston rod.

Evaluation of the cytotoxicity of new formulations of cariostatic agents containing nano silver fluoride: an in vitro study.

The objective of the study was to assess the indirect cytotoxicity of 600ppm and 1500ppm nano silver fluoride (NSF) compared to other commercial cariostatic agents. 56 dentin discs with 0.4mm in thickness were obtained from intact human molars and adapted to artificial pulp chambers (APCs). The discs were divided into seven groups according to treatment (n = 8): no treatment (positive control-PC), 29% hydrogen peroxide (negative control-NC), 30% Cariestop (CS30), 38% Riva Star (RS38), 38% Advantage Arrest (AA38), 600ppm NSF (NSF600), and 1500ppm NSF (NSF1500). The cariostatic agents were applied on the occlusal surface of the dentin discs (facing upward), and the pulp surface (facing downward) remained in contact with the culture medium. Immediately after the treatments, the extracts (DMEM + cariostatic agent components diffused through the discs) were collected and applied to MDPC-23 cells, which were assessed for viability (CV-alamarBlue, live/dead), adhesion/spreading (F-actin), alkaline phosphatase (ALP) activity, and mineralization nodule (MN) formation. The data were statistically analyzed by ANOVA/Games-Howell (p = 0.05). CV and ALP activity in CS30, RS38, AA38, and NSF600 were similar to PC (p > 0.05). MN formation significantly decreased only in NC, CS30, RS38, and AA38 compared to PC (p < 0.001). Only NSF600 and NSF1500 did not differ from PC (p > 0.05) with mineralization nodules, and this specific cell activity significantly decreased in all other groups (p < 0.05). NSF solutions (600ppm and 1500ppm) did not cause transdentinal toxicity on MDPC-23 cells.