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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 1,099 records · Page 61
All sourcesNASA NTRSDOE OSTI
DOE OSTI2019

Synthesis of novel α-aminophosphonates under microwave irradiation, biological evaluation as antiproliferative agents and apoptosis inducers

The synthesis of two series of α-aminophosphonates was achieved by Microwave Irradiation (MW), using the one-pot Kabachnik–Fields reaction. Based on a green chemistry approach, the reactions were carried out using ethanol as the only solvent and without any catalyst, and short reaction times (20–40 min), in variable yields. Both series were tested to determine their cell proliferation inhibition activity in MDA-MB-231, MCF-7 and MCF-10A cell lines. Ethyl 4-(((diphenoxyphosphoryl)(4-(diphenylamino)phenyl)methyl)amino) benzoate 4e and diphenyl (((4-(((S)-2-hydroxy-1-phenylethyl)carbamoyl)phenyl)amino)(4-hydroxyphenyl)methyl)phosphonate 6b, showed cell proliferation inhibition activity only in the cancer cell line MCF-7 and no effect on the normal cell line MFC-10A, both compounds caused cell death by inducing apoptosis.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2013

Transcatheter Arterial Embolization With Spherical Embolic Agent for Pulmonary Metastases From Renal Cell Carcinoma

Purpose: This retrospective study aimed to evaluate the safety and local efficacy of transcatheter arterial embolization (TAE) with superabsorbent polymer microspheres (SAP-MS) in patients with pulmonary metastases from renal cell carcinoma (RCC). Methods: Sixteen patients with unresectable pulmonary metastases from RCC refractory to standard therapy were enrolled to undergo TAE with the purpose of mass reduction and/or palliation. The prepared SAP-MS swell to approximately two times larger than their dry-state size (100-150 {mu}m [n = 14], 50-100 {mu}m [n = 2]). Forty-nine pulmonary nodules (lung n = 22, mediastinal lymph node n = 17, and hilar lymph node n = 10) were selected as target lesions for evaluation. Local tumor response was evaluated 3 months after TAE according to Response Evaluation Criteria in Solid Tumors (RECIST; version 1.1). The relationship between tumor enhancement ratio by CT during selective angiography and local tumor response was evaluated. Results: The number of TAE sessions per patient ranged from 1 to 5 (median 2.9). Embolized arteries at initial TAE were bronchial arteries in 14 patients (87.5 %) and nonbronchial systemic arteries in 11 patients (68.8 %). Nodule-based evaluation showed that 5 (10.2 %) nodules had complete response, 17 (34.7 %) had partial response, 15 (30.6 %) had stable disease, and 12 (24.5 %) had progressive disease. The response rate was significantly greater in 22 lesions that had a high tumor enhancement ratio than in 27 lesions that had a slight or moderate ratio (90.9 vs. 7.4 %, p = 0.01). Severe TAE-related adverse events did not occur. Conclusion: TAE with SAP-MS might be a well-tolerated and locally efficacious palliative option for patients with pulmonary metastases from RCC.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2018

Effects of Different Mixing Agents on the Stability of Sodium Tetradecyl Sulfate (STS) Foam: An Experimental Study

PurposeTo evaluate the effect of air, CO{sub 2} and contrast medium-air on the dwell time (DT) stability of sodium tetradecyl sulfate (STS) foam.Materials and MethodsThree types of foam sclerosants (air-foam, CO{sub 2}-foam, contrast-air-foam) were injected eight times into an inclined straight plastic tube (internal diameters 4 mm and 10 mm) filled with a blood substitute. Injections were captured by CCD camera, and images were transferred for digital analysis and calculation of DT.ResultsContrast-air-foam and air-foam in a 4-mm tube showed 5.6-/3.3-fold greater DT compared to CO{sub 2}-foam, respectively (P = 0.001). Contrast-air-foam in a 10-mm tube showed 2.1-fold greater DT compared to CO{sub 2}-foam (P = 0.0167).ConclusionA mixture of air and iodinated contrast improves the stability of STS foam compared to mixtures using only air or CO{sub 2}. Further, animal and clinical studies are needed to validate this in vitro result.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2018

Recent Advances in Copper Intercalators as Anticancer Agents

Copper is a part of various enzymes and helps them to function properly. It can be effectively used to produce promising anticancer drugs and presently, many studies are being pursued worldwide on the development of copper-based complexes as potential anticancer drugs. Herein, we briefly discuss the importance of reactive oxygen species in biological applications and copper(II) complexes as anticancer drugs. The anti-angiogenic properties of mono-nuclear copper(II) complexes have been demonstrated by in vivo chick embryo angiogenesis analysis. The plausible mechanism behind anticancer activity of these complexes is by the formation of excessive intracellular Reactive Oxygen Species (ROS). ROS is a composite term used for oxygen derivative non-radicals and free radicals of highly reactive components, that enhances the killing response of immune cells to microbial invasion. Previous reports have shown that ROS plays an important role as a messenger in cell cycling and normal cell signal transduction. .

60 APPLIED LIFE SCIENCES↗
DOE OSTI2018

Glutaraldehyde as Ambient Temperature Crosslinking Agent of Latex Films from Natural Rubber Grafted with Poly(diacetone acrylamide)

The concept of using glutaraldehyde (GTA) to crosslink natural rubber (NR) particles bearing diacetone acrylamide (DAAM) functional groups during film formation was investigated in the present work. The primary advantage of this curing system is that it is feasible under ambient conditions, which can lower operating costs of the curing process. Graft copolymers of NR and poly(diacetone acrylamide) prepared with 5 wt% of DAAM (NR–g–PDAAM5) were synthesized by seeded emulsion polymerization at 50 °C. Then, the tensile properties were measured for cast films formed from NR–g–PDAAM5 latex in the absence and presence of GTA. The results revealed increased tensile strength of the NR–g–PDAAM5 film, when GTA was added into the latex prior to film casting. The crosslinking of NR–g–PDAAM5 latex film by reaction with GTA, after film casting, was also investigated using attenuated total reflection Fourier transform infrared (ATR–FTIR) and dynamic mechanical thermal analysis (DMTA). ATR–FTIR analysis demonstrated that crosslinking reactions formed conjugated C=C double bonds between the active carbonyl groups of DAAM and GTA. The complementary use of DMTA also corroborated that crosslinking reactions took place involving the grafted PDAAM chains on the NR particles. This was evidenced by a clear shift towards higher temperatures of the tan δ peak, corresponding to the T{sub g} of NR–g–PDAAM phase, when GTA was incorporated into the NR–g–PDAAM5 latex before film formation. Additionally, a noticeable increase in thermal stability of the NR–g–PDAAM5 film was also observed with added GTA. Hence, it can be concluded that GTA is an efficient room-temperature crosslinker for NR particles functionalized with DAAM. This curing system can also be considered an alternative, simple, and inexpensive method for curing NR latex compounds, as only one component (GTA) is required in the curing process.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Preparation and Thermophysical Investigations of CoFe{sub 2}O{sub 4}-based Nanofluid: a Potential Heat Transfer Agent

Cobalt ferrite nanoparticles were synthesized by employing chemical co-precipitation technique. The structure, morphology, elemental composition, and magnetization studies of cobalt ferrite nanoparticles were carried by XRD, FE-SEM, EDS, and VSM techniques, respectively. Rietveld refined XRD pattern exhibited the single-phase cubic spinel structure with Fd-3m space group. FE-SEM images indicated some agglomeration of spherical grains which can be attributed to high surface energy and magnetic interactions. Presence of peaks of respective elements (Co, Fe, and O) in EDS spectrum showed formation of CoFe{sub 2}O{sub 4}. The M–H loop recorded at 300 K revealed superparamagnetic behavior and explained by fine particles size. The blocking temperature of the CoFe{sub 2}O{sub 4}nanoparticles from FC-ZFC curve was found to be 144 K. Cobalt ferrite–ethylene glycol nanofluids of various concentrations 0.0–1.0% in steps of 0.2% were prepared by ultrasonically assisted two-step technique. Thermophysical parameters such as thermal conductivity, specific heat, viscosity, and density were investigated as a function of both volume fraction and temperature. The experimental and theoretical value of each sample was correlated. The thermal conductivity was significantly enhanced with an increase in volume fraction and temperature.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Assessing Activity of Antimicrobial Agents and Screening Antibiotic-Resistant Bacteria Through DREAM Assay

Antibiotics have assumed importance in the scene of medicine due to their activity against bacterial infections. During the course of evolution, bacteria have been developing routes to overcome damaging effects of antibiotics. Antibiotic resistance is an intriguing development that has taken the world of anti-microbial therapy by storm. Among the methods described in literature for assessing anti-microbial activity, those using metabolic activity as a measure of bacterial viability provide estimates closer to the actual. The dye reduction-based electron-transfer activity monitoring assay (DREAM assay) utilizes the redox dye methylene blue as an indicator of microbial activity. The DREAM assay coefficient is presented herein as a measure of the extent of microbial reduction of methylene blue to a colorless form under experimental conditions. This novel metric was successfully employed to evaluate activity of three common antibiotics—ampicillin, gentamicin, and ciprofloxacin—and leaf extracts of Azadirachta indica and Ocimum sanctum. Results corroborated significantly with the conventional disk diffusion method commonly used for anti-microbial testing. The principle of microbial electron transfer was then successfully extended to assess antibiotic susceptibility of known resistant and sensitive strains of Escherichia coli. This method possesses the advantage of detecting anti-microbial activity in a simple, cost-effective, and rapid manner.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2026

Change Agent: Energy Storage as a Driver of Regulatory Evolution

Purpose of Review Dividing the electric grid into the functions of generation, transmission, anddistribution enabled the drawing of jurisdictional lines and the application of the U.S.Constitution’s federalist system to energy regulation. Energy storage technologies,which can be placed throughout the grid to increase flexibility, can provide serviceacross all three of those functions. But the jurisdictional boundaries that have beendrawn around those functions have created barriers that restrict energy storagetechnologies from achieving their full potential. This review analyzes regulatory changes made to reduce barriers to storage deployment and their broader impacts on energy regulation in the U.S. Recent Findings Major energy regulations promulgated at the state and federal levels have generally focused on liberalizing the U.S. electric system through deregulation and increased competition. Paradoxically, however, these efforts have erected strict regulatory barriers that prevent energy storage technologies from providing service across multiple functions. A new wave of regulations in recent years has endeavored to reduce and remove those barriers. Summary Energy regulations adopted in recent years to reduce barriers to energy storage functionality in recent years have had deep and far-reaching impacts on U.S. electric regulation. These impacts go beyond storage and affect all energy technologies. This paper traces the development of energy regulation in U.S., the functional barriers that they created that impede energy storage functionality, recent efforts to remove those barriers, and the broader effects of those efforts. It concludes with a brief discussion of remaining barriers that prevent energy storage from reaching their full potential on the U.S. electric grid.

24 POWER TRANSMISSION AND DISTRIBUTION↗