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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 1,045 records · Page 58
All sourcesNASA NTRSDOE OSTI
NASA NTRSDate not supplied

Composite Bond Line Measurements Based on A Bayesian Analysis of Flash Thermography Data

For bonded composite materials, an accurate characterization of the adhesive bond line is needed to predict failure modes and fracture toughness. In this paper, bond line thickness was estimated from data obtained using through transmission flash thermography. The forward model that predicts back surface temperature is based on a three layer heat diffusion equation with varying diffusivity and flux boundary conditions. The corresponding inverse problem of estimating bond line thickness from measurement data was solved using a Bayesian approach that assumed Gaussian priors for the bond line thickness and thermal diffusivity of the adherends. Finally, the outputs of the thermography based method were compared to measurements that were collected using a micrometer and ultrasound testing.

Flash thermography↗
NASA NTRSDate not supplied

Composite Bond Line Measurements Based on a Bayesian Analysis of Flash Thermography Data

For bonded composite materials, an accurate characterization of the adhesive bond line is needed to predict failure modes and fracture toughness. In this paper, bond line thickness was estimated from data obtained using through transmission flash thermography. The forward model that predicts back surface temperature is based on a three layer heat diffusion equation with varying diffusivity and flux boundary conditions. The corresponding inverse problem of estimating bond line thickness from measurement data was solved using a Bayesian approach that assumed Gaussian priors for the bond line thickness and thermal diffusivity of the adherends. Finally, the outputs of the thermography based method were compared to measurements that were collected using a micrometer and ultrasound testing.

Flash thermography↗
DOE OSTI2016

Development of an Ultrasonic Phased Array System for Wellbore Integrity Evaluation and Near-Wellbore Fracture Network Mapping of Injection and Production Wells in Geothermal Energy Systems

This paper documents our progress developing an ultrasound phased array system in combination with a model-based iterative reconstruction (MBIR) algorithm to inspect the health of and characterize the composition of the near-wellbore region for geothermal reservoirs. The main goal for this system is to provide a near-wellbore in-situ characterization capability that will significantly improve wellbore integrity evaluation and near well-bore fracture network mapping. A more detailed image of the fracture network near the wellbore in particular will enable the selection of optimal locations for stimulation along the wellbore, provide critical data that can be used to improve stimulation design, and provide a means for measuring evolution of the fracture network to support long term management of reservoir operations. Development of such a measurement capability supports current hydrothermal operations as well as the successful demonstration of Engineered Geothermal Systems (EGS). The paper will include the design of the phased array system, the performance specifications, and characterization methodology. In addition, we will describe the MBIR forward model derived for the phased array system and the propagation of compressional waves through a pseudo-homogenous medium.

MBIR↗
DOE OSTI2020

Stress‐Induced Domain Wall Motion in a Ferroelastic Mn 3+ Spin Crossover Complex

Abstract Domain wall motion is detected for the first time during the transition to a ferroelastic and spin state ordered phase of a spin crossover complex. Single‐crystal X‐ray diffraction and resonant ultrasound spectroscopy (RUS) revealed two distinct symmetry‐breaking phase transitions in the mononuclear Mn 3+ compound [Mn(3,5‐diBr‐sal 2 (323))]BPh 4 , 1. The first at 250 K, involves the space group change Cc → Pc and is thermodynamically continuous, while the second, Pc → P 1 at 85 K, is discontinuous and related to spin crossover and spin state ordering. Stress‐induced domain wall mobility was interpreted on the basis of a steep increase in acoustic loss immediately below the the Pc ‐ P 1 transition

Jakobsen, Vibe B.↗
DOE OSTI2023

Beyond Solvothermal: Alternative Synthetic Methods for Covalent Organic Frameworks

Abstract Covalent organic frameworks (COFs) are crystalline porous organic materials that hold a wealth of potential applications across various fields. The development of COFs, however, is significantly impeded by the dearth of efficient synthetic methods. The traditional solvothermal approach, while prevalent, is fraught with challenges such as complicated processes, excessive energy consumption, long reaction times, and limited scalability, rendering it unsuitable for practical applications. The quest for simpler, quicker, more energy‐efficient, and environmentally benign synthetic strategies is thus paramount for bridging the gap between academic COF chemistry and industrial application. This Review provides an overview of the recent advances in alternative COF synthetic methods, with a particular emphasis on energy input. We discuss representative examples of COF synthesis facilitated by microwave, ultrasound, mechanic force, light, plasma, electric field, and electron beam. Perspectives on the advantages and limitations of these methods against the traditional solvothermal approach are highlighted.

Hu, Jiyun↗
DOE OSTI2023

Beyond Solvothermal: Alternative Synthetic Methods for Covalent Organic Frameworks

Abstract Covalent organic frameworks (COFs) are crystalline porous organic materials that hold a wealth of potential applications across various fields. The development of COFs, however, is significantly impeded by the dearth of efficient synthetic methods. The traditional solvothermal approach, while prevalent, is fraught with challenges such as complicated processes, excessive energy consumption, long reaction times, and limited scalability, rendering it unsuitable for practical applications. The quest for simpler, quicker, more energy‐efficient, and environmentally benign synthetic strategies is thus paramount for bridging the gap between academic COF chemistry and industrial application. This Review provides an overview of the recent advances in alternative COF synthetic methods, with a particular emphasis on energy input. We discuss representative examples of COF synthesis facilitated by microwave, ultrasound, mechanic force, light, plasma, electric field, and electron beam. Perspectives on the advantages and limitations of these methods against the traditional solvothermal approach are highlighted.

Hu, Jiyun↗
DOE OSTI2023

Breast tumor-targeted drug delivery via polymer nanocarriers: Endogenous and exogenous strategies

Breast cancer, one of the most common types of cancer worldwide, has a high degree of malignancy while lacking efficient treatments. The off-target events frequently occurring in drug administration have been a major obstacle, which causes severe side effects to patients and reduces the therapeutic efficacy. An ideal medication should precisely target the specific site with precise control over concentration and duration. In recent years, there has been immense progress in polymer nanocarriers that demonstrate great potential in the targeted delivery. These nanocarriers are constructed from materials sensitive to a wide range of endogenous (e.g., pH, enzyme, redox) and exogenous stimuli (e.g., light, ultrasound, magnetic waves), driving cargo release to the targeted tissue or cells. Here, we elucidate the mechanism of current targeting strategies and the engineering methods to construct these targeting systems or to improve their targeting efficiency. Here we capture the recent progress in the targeted nanocarriers derived from polymers which span hydrogels and micelles, demonstrating their design and applications in chemo, hyperthermia, immuno, and gene therapies.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Recurrent and convolutional neural networks for sequential multispectral optoacoustic tomography ( MSOT ) imaging

Abstract Multispectral optoacoustic tomography (MSOT) is a beneficial technique for diagnosing and analyzing biological samples since it provides meticulous details in anatomy and physiology. However, acquiring high through‐plane resolution volumetric MSOT is time‐consuming. Here, we propose a deep learning model based on hybrid recurrent and convolutional neural networks to generate sequential cross‐sectional images for an MSOT system. This system provides three modalities (MSOT, ultrasound, and optoacoustic imaging of a specific exogenous contrast agent) in a single scan. This study used ICG‐conjugated nanoworms particles (NWs‐ICG) as the contrast agent. Instead of acquiring seven images with a step size of 0.1 mm, we can receive two images with a step size of 0.6 mm as input for the proposed deep learning model. The deep learning model can generate five other images with a step size of 0.1 mm between these two input images meaning we can reduce acquisition time by approximately 71%.

Juhong, Aniwat↗
DOE OSTI2021

Novel compound heterozygous CPLANE1 variants identified in a Chinese family with Joubert syndrome

Abstract Joubert syndrome (JS) and JS‐related disorders (JSRD) are a group of neurodevelopmental diseases that share the “molar tooth sign” on axial brain magnetic resonance imaging (MRI), accompanied by cerebellar vermis hypoplasia, ataxia, hypotonia, and developmental delay. To identify variants responsible for the clinical symptoms of a Chinese family with JS and to explore the genotype–phenotype associations, we conducted a series of clinical examinations, including blood tests, brain MRI scans, ultrasound imaging, and ophthalmologic examination. Genomic DNA was extracted from the peripheral blood of the six‐person family, and the pathogenic variants were detected by whole‐exome sequencing (WES) and verified by Sanger sequencing. WES revealed two novel compound heterozygous variants in CPLANE1 : c.1270C>T (p.Arg424*) in exon 10 and c.8901C>A (p.Tyr2967*) in exon 48 of one child, inherited from each parent. Both variants were absent in ethnically matched Chinese control individuals and were either absent or present at very low frequencies in public databases, suggesting that these variants could be the pathogenic triggers of the JS phenotype. Notably, these CPLANE1 sequence variants were related to the pathogenesis of autosomal recessive JS in this study. The newly discovered variants expand the mutation spectrum of CPLANE1 , which assists in understanding the molecular mechanism underlying JS and improving the recognition of genetic counseling, particularly for families with a history of autosomal recessive JS.

Zhang, Cheng↗
DOE OSTI2013

Developing radiographer roles in the context of advanced and consultant practice

Skill-mix initiatives have provided opportunities for radiographers to develop roles and achieve their potential, thus contributing to radiographer retention rates and increased job satisfaction. This reflective article explores two radiographic roles within an interprofessional context including the implications for confidence, competence, and future sustainability. These were reporting roles which extended into two modalities, one into bone densitometry and another into ultrasound. This article discusses how successful skill mix can benefit the individual, their department, and NHS organization and that role expansion can develop a more dynamic and resourceful workforce with transferability of skills and attributes.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2019

Single Fe Atom on Hierarchically Porous S, N-Codoped Nanocarbon Derived from Porphyra Enable Boosted Oxygen Catalysis for Rechargeable Zn-Air Batteries

Iron-nitrogen-carbon materials (Fe-N-C) are known for their excellent oxygen reduction reaction (ORR) performance. Unfortunately, they generally show a laggard oxygen evolution reaction (OER) activity, which results in a lethargic charging performance in rechargeable Zn-air batteries. Here porous S-doped Fe-N-C nanosheets are innovatively synthesized utilizing a scalable FeCl 3 -encapsulated-porphyra precursor pyrolysis strategy. The obtained electrocatalyst exhibits ultrahigh ORR activity ( E 1/2 = 0.84 V vs reversible hydrogen electrode) and impressive OER performance ( E j=10 = 1.64 V). The potential gap (Δ E = E j=10 - E 1/2 ) is 0.80 V, outperforming that of most highly active bifunctional electrocatalysts reported to date. Furthermore, the key role of S involved in the atomically dispersed Fe-N x species on the enhanced ORR and OER activities is expounded for the first time by ultrasound-assisted extraction of the exclusive S source (taurine) from porphyra. Moreover, the assembled rechargeable Zn-air battery comprising this bifunctional electrocatalyst exhibits higher power density (225.1 mW cm -2 ) and lower charging-discharging overpotential (1.00 V, 100 mA cm -2 compared to Pt/C + RuO 2 catalyst). Here, the design strategy can expand the utilization of earth-abundant biomaterial-derived catalysts, and the mechanism investigations of S doping on the structure-activity relationship can inspire the progress of other functional electrocatalysts.

25 ENERGY STORAGE↗
DOE OSTI2019

Synthesis and bioassay of a new class of disubstituted 1,3,4-oxadiazoles, 1,3,4-thiadiazoles and 1,2,4-triazoles

A new class of aroylethenesulfonylmethyl styryl oxadiazoles/thiadiazoles/triazoles and arylsulfonylethenesulfonylmethyl styryl oxadiazoles/thiadiazoles/triazoles were synthesized from the synthetic intermediates E-aroylethenesulfonylacetic acid methyl ester, E-arylsulfonylethenesulfonylacetic acid methyl ester and substituted cinnamic acids adopting conventional and ultrasonication methodologies. All the synthesized compounds were obtained in higher yields and in shorter reaction times in ultrasound irradiation method when compared with conventional method. The structures of all the compounds were characterized by IR, {sup 1}H NMR, {sup 13}C NMR and mass spectra. All the title compounds were tested for antimicrobial activity. The arylsulfonylethenesulfonylmethyl styryl azoles displayed higher antimicrobial activity than the aroylethenesulfonylmethyl styryl azoles. The compounds having triazole moiety showed greater activity than those with oxadiazole and thiadiazole. Amongst all the tested compounds unsubstituted and chloro substituted arylsulfonylethenesulfonyl methyl styryl triazoles are identified as potential antimicrobial agents particularly against B. subtilis and P.chrysogenum. .

60 APPLIED LIFE SCIENCES↗
DOE OSTI2023

A combination interferometric and morphological image processing approach to rapid quality assessment of additively manufactured cellular truss core components

Advanced manufacturing (AM) processes such as laser powder bed fusion (LPBF) are increasingly capable of fabricating components with useful and unprecedented mechanical properties by incorporating complex internal bracing structures. From the standpoint of quality control and assessment, however, internally complex assemblies present significant build-verification challenges. Here we propose a hybrid approach to the inspection involving the application of computer-aided speckle interferometry (CASI) and morphological image processing as a rapid, inexpensive, and facile method for AM quality control. The described methodology has low capital equipment costs, is full-field and non-contact, can be used in an industrial setting, and has very low requirements in terms of operator training and expertise. Consisting primarily of the combination of image processing software with a simple optical system of variable sensitivity, the method is shown to be effective for inspection of a titanium honeycomb component subjected to differential pressure. Results are compared to those achieved with computed tomography (CT), immersion ultrasound testing (UT), and optical holographic interferometry. Here we propose several possible processing strategies for automated quality assessment based on this powerful hybrid approach.

36 MATERIALS SCIENCE↗
DOE OSTI2019

A case of immunoglobulin G4-related inflammatory pseudotumor mimicking renal cell carcinoma

In a 69-year-old woman with a history of Mikulicz’s disease, a hypoechoic solitary renal mass was identified on routine ultrasound examination. Based on the findings of computed tomography (CT) and magnetic resonance imaging (MRI), renal cell carcinoma was a possible diagnosis. Subsequent partial nephrectomy revealed a mass characterized by an increased number of blood vessels, internal hemorrhage, and a thick fibrous capsule. Immunohistochemically, the mass comprised of tubulointerstitial nephritis with increased immunoglobulin (Ig)G4-positive plasma cells and fibrosis. Generally, diagnosis of IgG4-related kidney disease (IgG4-RKD) is not difficult when the kidney is involved together with other systemic involvements. However, diagnosis becomes harder when a solitary renal mass appears as a single-organ involvement. On precise review of our imaging findings, MRI signals were markedly affected by hemorrhage, so the mass showed hypointensity on both T1- and T2-weighted imaging, and the signal of in-phase images decreased. Dynamic MRI showed no apparent enhancement of the mass, while CT showed an apparent enhancement effect. Capsule formation was another key finding for IgG4-RKD and was recognized as a gradually enhancing boundary zone surrounding the mass on both CT and MRI. When a solitary renal mass is associated with hemorrhage and thick capsule formation, inflammatory pseudotumor should be considered as differential diagnosis.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2019

Indirect percutaneous core needle biopsy of solid pancreatic or peripancreatic lesions

Solid pancreatic or peripancreatic lesions comprise a heterogeneous group of diseases that rely on a multimodality imaging approach for subsequent tissue procurement. Endoscopic ultrasound (EUS)-guided fine needle aspiration (FNA)/biopsy is an effective and safe method for tissue diagnosis in this region. The failure to obtain adequate tissue for diagnosis under EUS guidance is still a rare but important issue. Percutaneous core needle biopsy (CNB) provides an alternative pathway for adequate specimen acquisition. Because of the deep retroperitoneal location, the percutaneous biopsy of pancreatic or peripancreatic lesions may inevitably pass through visceral organs. The procedure is relatively risky and difficult for general radiologists, particularly beginners, and an adequate knowledge of the abdominal anatomy and biopsy technique is indispensable. In this review, various aspects of percutaneous CNB for solid pancreatic or peripancreatic lesions using different trans-organ approaches are reviewed to increase the chance of successful biopsy.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2019

Evaluation of acoustic radiation force impulse (ARFI) elastography as non-invasive diagnostic tool in living donor liver transplantation

Background and aims: Role of acoustic radiation force impulse (ARFI) elastography, in transplant setting, is not well established. We aimed to define the normal mean values of the liver stiffness by ARFI Elastography in healthy liver donors and to evaluate ARFI elastography as predictor of graft fibrosis post living donor liver transplant (LDLT) in comparison to other non-invasive methods (transient elastography [TE], APRI and FIB4). Patients and methods: A total of 100 subjects (70 recipients and 30 donors) were recruited. APRI and FIB4 scores were calculated for all recipients. TE and ARFI elastography (Siemens Acuson S2000 Ultrasound System, Germany) were performed to all subjects. All donors and only 30 recipients had liver biopsy. Significant fibrosis was defined as ≥ F2. Results: The mean ARFI velocity among the donors was 1.05 ± 0.09 m/s. Regarding the recipients: mean age was 49.5 ± 8.49 years, 85.7% males, fibrosis stages < F2 were the most frequent stages by liver biopsy (86.7%) and TE (67.1%). ARFI median was significantly correlated with TE median, APRI and FIB-4 (r = 0.888, p = 0.000; r = 0.62, p = 0.000, and r = 0.585, p = 0.000, respectively). ARFI performed well in discriminating patients with ≥ F2 (AUROC = 0.93, 95% CI 0.86–0.99, p < 0.01) with best cutoff median value of 1.34 m/s (sensitivity 90%, specificity 82%). Conclusion: ARFI can be used as a reliable method in assessment of significant fibrosis post-LDLT.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2019

Pathological variants of hepatocellular carcinoma on MRI: emphasis on histopathologic correlation

Hepatocellular carcinoma (HCC) is a unique tumor because it is one of the few cancers which can be treated based on imaging alone. Magnetic resonance imaging (MRI) carries higher sensitivity and specificity for the diagnosis of HCC than either computed tomography (CT) or ultrasound. MRI is imaging modality of choice for the evaluation of complex liver lesions and HCC because of its inherent ability to depict cellularity, fat, and hepatocyte composition with high soft tissue contrast. The imaging features of progressed HCC are well described. However, many HCC tumors do not demonstrate classical imaging features, posing a diagnostic dilemma to radiologists. Some of these can be attributed to variations in tumor biology and histology, which result in radiological features that differ from the typical progressed HCC. This pictorial review seeks to demonstrate the appearance of different variants of HCC on MRI imaging, in relation to their histopathologic features.

62 RADIOLOGY AND NUCLEAR MEDICINE↗