Maximum Lifetime Research Articles

Tailored Fabrication of Full-Color Ultrastable Room-Temperature Phosphorescence Carbon Dots Composites with Unexpected Thermally Activated Delayed Fluorescence.

The development of single-system materials that exhibit both multicolor room-temperature phosphorescence (RTP) and thermally activated delayed fluorescence (TADF) with tunable after glow colors and channels is challenging. In this study, four metal-free carbon dots (CDs) are developed through structural tailoring, and panchromatic high-brightness RTP is achieved via strong chemical encapsulation in urea. The maximum lifetime and quantum yield reaches 2141 ms and 56.55%, respectively. Moreover, CDs-IV@urea, prepared via coreshell interaction engineering, exhibits a dual afterglow of red RTP and green TADF. The degree of conjugation and functional groups of precursors affects the binding interactions of the nitrogen cladding on CDs, which in turn stabilizes triplet energy levels and affects the energy gap between S1 and T1 (ΔEST) to induce multicolor RTP. The enhanced wrapping interaction lowers the ΔEST, promoting reverse intersystem crossing, which leads to phosphorescence and TADF. This strong coreshell interaction fully stabilizes the triplet state, thus stabilizing the material in water, even in extreme environments such as strong acids and oxidants. These afterglow materials are tested in multicolor, time, and temperature multiencryption as well as in multicolor in vivo bioimaging. Hence, these materials have promising practical applications in information security as well as biomedical diagnosis and treatment.

LC filter optimized design considering the effect on the power converter and capacitor lifetimes

AbstractThis work presents an LC filter design methodology that considers the optimization of the converter as a whole: filter, semiconductor switches, and DC bus. The optimization is made in light of the system losses, volume, and the capacitors lifetime, discussing the advantages and disadvantages of decisions in the parametric design of the filter (of the values of L and C). The technology of components and construction challenges are considered in the design. The manuscript guides the design process of the filter in two steps: first, by providing the means to perform the parametric sweep of possible filter designs, according to the converter specifications and other restrictions; second, by describing how the hardware design is carried out and indicating the models and methods that are being used. Individualized analyses for each part of the converter system are made, and using the proposed methodology, three design examples are provided and analyzed, each choosing the filter parameters with different objectives: minimum volume, maximum capacitor lifetime, or maximum efficiency. Results show that using Kool M material results in the lowest filter volumes and losses. It is also shown that for the DC bus design, there is a compromise between volume and lifetime, with a greater number of capacitors increasing both attributes. By designing the system using the proposed methodology, the minimum volume is achieved at an operating point that differs from the individual minimum volumes of the filter and the inverter, and the lifetime is only 1.78% than the maximum lifetime point.

Constructing Connected-Dominating-Set with Maximum Lifetime in Cognitive Radio Networks

Connected-dominating-set (CDS) is a representative technique for constructing virtual backbones of wireless networks and thus facilitates implementation of many tasks including broadcasting, routing, etc. Most of existing works on CDS aim at constructing the minimum CDS (MCDS), so as to reduce the communication overhead over the CDS. However, MCDS may not work well in cognitive radio networks (CRNs) where communication links are prone to failure due to stochastic activities of primary users (PUs). A MCDS without consideration of the stochastic activities of PUs easily becomes invalid when the PUs become active. This study addresses a new CDS construction problem by considering the PUs’ activities. Our problem is to maximize the lifetime of the CDS while minimizing the size of the CDS, where the lifetime of a CDS is defined as the expected duration that the CDS is maintained valid. We show that the problem is NP-hard and propose a three-phase centralized algorithm. Given a CRN, the centralized algorithm can compute a CDS such that the lifetime of the CDS is maximized (optimal), and the size of the CDS is upper-bounded. We further present a two-phase localized algorithm which requires 2-hop information. Extensive simulations are conducted to evaluate the proposed algorithms.

Abstract 679: TXB-001 is an upgraded conjugated anthracycline that targets tumors with reduced risk of cardiotoxicity, hand-foot syndrome and alopecia

Abstract TXB-001 is a well-optimized N-(2-hydroxypropyl)methacrylamide copolymer-based conjugated pirarubicin (THP) and a novel candidate for developing anticancer drugs. It exhibits tumor-specific accumulation due to the enhanced permeability and retention effects and prolonged circulation time compared with free THP. Its hydrazone bond is dissociated under lower pH conditions, providing selective and rapid release of THP in acidic tumor environments. Therefore, TXB-001 is expected to have high efficacy and low toxicity. Anthracycline anticancer drugs have been widely used for the treatment of several cancers, but their use is limited by several adverse effects (AEs), including cardiotoxicity, which is a life-threatening AE. Furthermore, the maximum lifetime cumulative dose is decided for each anthracycline in clinical use, which leads to discontinuation of the medication. Hand-foot syndrome (HFS) is a dose-limiting AE of DOXIL®, a liposomal formulation of doxorubicin (DOX), and although it is not a life-threatening condition, it significantly deteriorates quality of life (QOL). Alopecia is another common AE, which is relatively noninvasive but adversely affects mental health and reduces QOL. In this study, we confirmed the efficacy of TXB-001 in a mice triple-negative breast cancer (TNBC) model and evaluated the cardiotoxicity-, HFS- and alopecia-inducing effects of TXB-001 in mice and rats to compare the severity with existing anthracycline anticancer drugs, including DOXIL®. The pharmacokinetic (PK) analysis in several tissues, including plasma, tumor, heart, skin of the chest, and palmar and plantar areas, was also performed after a single intravenous administration in rodents. As a result, TXB-001 showed an equivalent or greater antitumor effects than other anthracyclines in the TNBC model, and the AEs were scarcely observed. TXB-001 did not decrease left ventricular ejection fraction, with no or little HFS-like changes compared with DOXIL®, which showed significant histopathological changes. TXB-001 also showed weaker alopecia-inducing effects than DOX, DOXIL®, and THP. In the PK analysis, TXB-001 was distributed in the tumor at a higher concentration than in other tissues, except for plasma. Hence, most of the THP, the active ingredient, was released in the tumor. The exposure of the heart in the TXB-001-treated group was one-tenth of that in the DOXIL®-treated group. Moreover, accumulation in the skin, especially in palmar and plantar areas, was observed for DOXIL®, but no accumulation in the skin was observed for TXB-001. This PK profile consistently demonstrated the antitumor activity of TXB-001, without AEs. TXB-001 reduces the chance of dose-limiting and QOL-threatening AEs, and thus, cancer patients can continue treatment, making it a more convenient anticancer drug in clinical use with a wide safety margin. Citation Format: Keiyu Oshida, Mikito Hirakata, Emi Tomikawa, Chizuka Sakai, Masashi Uchida, Rieko Shimozono, Akiko Izawa, Yoko Koga, Tsubasa Okano, Hideki Narumi, Lisa Munakata, Ryo Suzuki, Miki Nonaka, Yasuhito Uezono. TXB-001 is an upgraded conjugated anthracycline that targets tumors with reduced risk of cardiotoxicity, hand-foot syndrome and alopecia [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 679.

Reducing emissions from production and distribution in three-echelon supply chains

Reducing carbon emissions is one of the key goals of contemporary supply chains and logistics. This paper aims to formulate a novel three-echelon (supplier-3PL-retailer) supply chain model comprising green technology investment, variable demand, variable lead time, a dynamic shipping strategy, and an option for vehicle selection. The demand function considers the product's freshness index and maximum lifetime, along with the availability of stocks. Besides, the delivery from the 3PL to the retailer is dynamically determined based on previous shipment information. A green vehicle is selected using a multi-criteria decision-making (MCDM) technique based on q-alternatives with n-characteristics for the transportation process and mathematically we link this selection process to traditional three echelon supply chain optimization problem. The results show that combining green investment with an appropriate dynamic shipping strategy by using a selected green vehicle reduces the supply chain's emissions and total integrated cost. Furthermore, reducing lead time without compromising other supply chain factors stimulates demand of customers and produces fewer emissions with a significant reduction in the total integrated cost. A real-case-based study shows the performance of the proposed model and method.. The study illustrates that 47.744% of the carbon emissions in Scenario 1 and 47.53% in Scenario 2 are reduced when an emission reduction strategy is implemented. In terms of total integrated costs our proposed model could save 4.85% cost in Scenario 1 while 4.96% for Scenario 2, which is significant.

Mission lifetime optimisation with self or assisted disposal

Operation to failure was the modus operandi of most satellite operators prior to the awareness of the impact on the space debris environment. While compliance to space debris mitigation guidelines, standards and regulations is clearly a priority, there remains a business advantage in extracting the maximum lifetime out of any in-orbit asset. For certain types of strategic assets, which provide unique societal benefits through their missions and are typically irreplaceable, due to their complexity, cost and public funding sources, it becomes imperative to ensure extraction of maximum mission value while fully respecting the need for a sustainable orbital environment. With reference to mission examples in EUMETSAT, this paper highlights: the techniques which have already been used to ensure compliant end-of-life strategies while extending mission lifetimes on satellites not designed to support disposal; the approaches made on new generation satellites to achieve compliance with the debris mitigation standards, highlighting what this brings, but also risks remaining for debris mitigation and lifetime value optimisation; how an Active Debris Removal service in LEO positively impacts the lifetime extension/debris mitigation risk trade-off, describing the potential business case for such services on high value, strategic assets.

Dynamics of cavitation bubbles in viscous liquids in a tube during a transient process

We experimentally, numerically, and theoretically investigate the dynamics of cavitation bubbles in viscous liquids in a tube during a transient process. In experiments, cavitation bubbles are generated by a modified tube-arrest setup, and the bubble evolution is captured with high-speed imaging. Numerical simulations using OpenFOAM are employed to validate our quasi-one-dimensional theoretical model, which effectively characterizes the bubble dynamics. We find that cavitation onset is minimally affected by the liquid viscosity. However, once cavitation occurs, various aspects of bubble dynamics, such as the maximum bubble length, bubble lifetime, collapse time, and collapse speed, are closely related to the liquid viscosity. We further establish that normalized bubble dynamics are solely determined by the combination of the Reynolds number and the Euler number. Moreover, we also propose a new dimensionless number, Ca2, to predict the maximum bubble length, a critical factor in determining the occurrence of liquid column separation.

Controlled self-assembly of the perylene bisimides into rectangular and ribbon-like nanostructures

Fabricating nanostructures by the perylene bisimides (PBIs) has attracted great interests, but control over the shapes and sizes is still challenge. Herein, two chiral PBIs synthesized by 3,4,9,10-perylene tetracarboxylic dianhydride, D-alanine (or L-alanine) and triethylene glycol monomethyl ether have been developed. A serious of H-aggregated two-dimensional (2D) nanostructures from rectangular nanostructures to ribbon-like nanostructures are self-assembled by the two PBIs through a heating, cooling and aging process in alcoholic solvents and deionized water. The aspect ratios, shapes and sizes of the 2D nanostructures could be controlled by tailoring the dissolving capacity of the solvents. The van der Waals' force and the π-π stacking interaction play key roles in the formation of the 2D nanostructures. The optical properties of the 2D nanostructures are observably influenced by the dissolving capacity of the solvents. The S0-1 vibronic transition of the perylene skeletons is confirmed to generate a strong non-radiative energy transfer in deionized water. The maximum phosphorescence lifetime is greater than 2.2 ms in deionized water. This study will offer a new view to prepare the 2D nanostructures which could be used as sensors and photocatalysts.

Phosphorescent fac-Bis(triarylisocyanide) W(0) and Mo(0) Complexes.

Homoleptic W(0) and Mo(0) complexes containing bis(triarylisocyanide) ligands with bulky substituents were synthesized and spectroscopically characterized. Crystallographically determined structures revealed that these complexes are hourglass-like in shape with the tridentate ligands adopting a facial coordination mode to the metal center. These complexes luminesce in fluid solutions and in the solid state. Typically in toluene at 298 K, the two W(0) complexes display the emission maximum (lifetime and quantum yield) at 591 nm (0.83 μs and 0.35) and 628 nm (1.04 μs and 0.39), and similarly, the two Mo(0) complexes display it at 575 nm (0.54 μs and 0.15) and 617 nm (0.56 μs and 0.23). DFT and TDDFT calculations indicated that the low-energy absorption bands of the W(0) and Mo(0) complexes could be metal-to-ligand charge transfer (MLCT) transitions in nature. These complexes exhibited a reversible M+/0 redox couple at -0.70 and -0.63 V vs Fc+/0 for the W(0) complexes and -0.86 and -0.67 V for the Mo(0) complexes. The excited-state reduction potentials were hence estimated to be -2.91 and -2.74 V vs Fc+/0 for the W(0) complexes and -3.10 and -2.81 V vs Fc+/0 for the Mo(0) complexes, indicating that they are potentially strong photoreductants.

Realized thermal niche approach eliminates temperature bias in bioenergetic model estimates.

Bioenergetics models estimate ectotherm growth, production, and prey consumption - all key for effective ecosystem management during changing global temperatures. Based on species-specific allometric and thermodynamic relationships, these models typically use the species' lab-derived optimum temperatures (physiological optimum) as opposed to empirical field data (realized thermal niche) that reflect actual thermal experience. Yet, dynamic behavioral thermoregulation mediated by biotic and abiotic interactions may provide substantial divergence between physiological optimum and realized thermal niche temperatures to significantly bias model outcomes. Here, using the Wisconsin bioenergetics model and in-situ year-round temperature data, we tested the two approaches and compared the maximum attainable lifetime weight and lifetime prey consumption estimates for two salmonid species with differing life histories. We demonstrate that using the realized thermal niche is the better approach because it eliminates significant biases in estimates produced by the physiological optimum. Specifically, using the physiological optimum, slower-growing Salvelinus namaycush maximum attainable lifetime weight was underestimated, and consumption overestimated, while fast-growing Oncorhynchus tshawytscha maximum attainable weight was overestimated. While the physiological optimum approach is useful for theoretical studies, our results demonstrate the critical importance that models used by management utilize up-to-date system- and species-specific field data representing actual in-situ behaviors (i.e., realized thermal niche).

Ultracold field-linked tetratomic molecules.

Ultracold polyatomic molecules offer opportunities1 in cold chemistry2,3, precision measurements4 and quantum information processing5,6, because of their rich internal structure. However, their increased complexity compared with diatomic molecules presents a challenge in using conventional cooling techniques. Here we demonstrate an approach to create weakly bound ultracold polyatomic molecules by electroassociation7 (F.D. et al., manuscript in preparation) in a degenerate Fermi gas of microwave-dressed polar molecules through a field-linked resonance8-11. Starting from ground-state NaK molecules, we create around 1.1 × 103 weakly bound tetratomic (NaK)2 molecules, with a phase space density of 0.040(3) at a temperature of 134(3) nK, more than 3,000 times colder than previously realized tetratomic molecules12. We observe a maximum tetramer lifetime of 8(2) ms in free space without a notable change in the presence of an optical dipole trap, indicating that these tetramers are collisionally stable. Moreover, we directly image the dissociated tetramers through microwave-field modulation to probe the anisotropy of their wavefunction in momentum space. Our result demonstrates a universal tool for assembling weakly bound ultracold polyatomic molecules from smaller polar molecules, which is a crucial step towards Bose-Einstein condensation of polyatomic molecules and towards a new crossover from a dipolar Bardeen-Cooper-Schrieffer superfluid13-15 to a Bose-Einstein condensation of tetramers. Moreover, the long-lived field-linked state provides an ideal starting point for deterministic optical transfer to deeply bound tetramer states16-18.

Tool life assessment of high strength cast iron alloys in dry face milling operations

The advancement in cast iron alloy properties has led to more efficient materials, especially in the automotive industry. However, this progress has also increased the demand for more durable tools with greater resistance to cutting operations. Conducting an in-depth investigation into the impact of these materials on tool lifespan is crucial, as it directly affects productivity. The main objective of this study was to analyze the lifespan of uncoated cemented carbide tools during milling operations using four high-strength cast iron alloys under various dry cutting conditions. A full factorial Design of Experiment (DoE) (23) was employed. The input variables included cutting speed (vc) of 230 and 350 m/min, tool feed (fz) of 0.1 and 0.2 mm/tooth, and materials, namely cast irons (FC 250, FC 300(Mo), FC300(Mo+RG), and FV 450). Additionally, material tests were conducted on billets without holes to simulate mild cutting conditions and with holes for more severe machining conditions. The established machining operation was face milling without cutting fluid, with the axial depth of cut (ap) and radial depth of cut (ae) maintained constant at 1 mm and 60 mm, respectively. The results showed that FV 450 had the shortest tool life, as expected for the hardest and resistant material, with a maximum lifetime difference of 83 % less when compared to FC 250, the softest one that had the longest tool lifespan. The introduction of holes also significantly reduced the overall tool life by about 57 %. The findings highlight the importance of factors such as cutting speed, feed per tooth, material composition, impact, and workpiece surface quality, which significantly influence tool performance.

Metal-Free organic polymeric room temperature phosphorescence system with Multi-Colour and ultralong lifetime

Room-temperature-phosphorescent (RTP) metal-free organic polymer materials with long-lasting luminescence properties have received considerable attention in the field of optical materials. Herein, we report unique RTP polymeric materials with ultralong-lasting multicolor luminescence prepared using a series of organic phosphorescent guest molecules and melamine formaldehyde resins. Because of facile thermal cross-linking, these materials exhibit a stable multicolor long-lasting afterglow with a maximum phosphorescence lifetime of > 1 s and a maximum phosphorescence emission efficiency of up to 3.4 %. In addition, polymer doping systems with flexible processability were easily printed on 2D substrates and further used as patterned security labels with full-color dynamic phosphorescence. Further, different materials were combined to form a ternary digital encryption system. In addition, although reports on 3D-printed phosphorescent materials are scarce, by using a similar thermoforming method, we successfully prepared a 3D-molding phosphorescent material that can exhibit a satisfactory long-lasting afterglow even after it is kept underwater for 30 days. In conclusion, this work will usher in advancements in the development and application of metal-free polymer-based RTP materials with long-lasting luminescence and 3D printing potential.

Cross-cultural validation and psychometric properties of the Spanish version of the quality of life in Childhood epilepsy Questionnaire (QOLCE-55)

ObjectiveThe aims of the present study were to translate and validate the Quality of Life in Childhood Epilepsy Questionnaire (QOLCE-55) into Spanish. MethodsA backtranslation procedure was used to translate the English version of QOLCE-55 to Spanish, and subsequently, parents of 88 children (aged four to 12 years), completed the Spanish version of three self-reported questionnaires: the QOLCE-55, the Pediatric Quality-of-Life Inventory (PedsQLTM 4.0), and the Pediatric Sleep Questionnaire (PSQ). Seven to 10 days later, parents completed the questionnaires again under the same conditions. ResultsInternal consistency was between 0.669 and 0.968 for the four subscales: cognitive (CF), emotional (EF), social (SF) and physical functioning (PF); and 0.954 for the total score. The test–retest reliability assessed with the intraclass correlation coefficient obtained values from 0.683 for SF to 0.962 for CF. The standard error of measurement for the total score was 5.776, and the minimal detectable change was 16.01. Spearman correlations between the total score of the Spanish version of the QOLCE-55 with the subscales was 0.760 for the CF, 0.776 for the EF, 0.799 for the SF, and 0.682 for the PF (p < 0.001). Convergent validity of QOLCE-55 with the PedsQLTM 4.0 scale was −0.962 (p < 0.001), and the discriminant validity of the QOLCE-55 with PSQ was 0.154 (p = 0.272). This version presented a correlation with maximum lifetime consumption of anti-epileptic drugs (0.500; p < 0.001), and current consumption (0.448; p < 0.001). ConclusionsThe Spanish version of the QOLCE-55 has demonstrated adequate psychometric properties, indicating that it can be confidently used to measure the health-related quality-of-life (HRQoL) in children with epilepsy in a Spanish-speaking population. These results corroborate the instrument's cross-cultural validity.

Dynamic Transition between Monomer and Excimer Phosphorescence in Organic Near-Infrared Phosphorescent Crystals.

Achieving efficient near-infrared room-temperature phosphorescence of purely organic phosphors remains scarce and challenging due to strong nonradiative decay. Additionally, the investigation of triplet excimer phosphorescence is rarely reported, despite the fact that excimer, a special emitter commonly formed in crystals with strong π-π interactions, can efficiently change the fluorescent properties of compounds. Herein, a series of dithienopyrrole derivatives with low triplet energy levels and stable triplet states, exhibiting persistent near-infrared room-temperature phosphorescence, is developed. Via the modification of halogen atoms, the crystals display tunable emissions of monomers from 645 to 702nm, with a maximum lifetime of 3.68ms under ambient conditions. Notably, excimer phosphorescence can be switched on at low temperatures, enabled by noncovalent interactions rigidifying the matrix and stabilizing triplet excimer. Unprecedentedly, the dynamic transition process is captured between the monomer and excimer phosphorescence with temperature variations, revealing that the unstable triplet excimers in crystals with a tendency to dissociate can result in the effective quench of room-temperature phosphorescence. Excited state transitions across varying environments are elucidated, interpreting the structural dynamics of the triplet excimer and demonstrating strategies for devising novel near-infrared phosphors.

Genetic evaluation of crossbred Bos indicus cow temperament at parturition.

Cow temperament at parturition may be mostly a measure of aggressiveness. The heritability of cow temperament at parturition in Bos taurus cows has been reported to be low. The objectives of this study were to estimate the heritability of cow temperament at parturition, conduct a genome-wide association analysis of cow temperament at the time of parturition, and estimate the correspondence of cow temperament at the time of parturition with cow productive performance and early-life temperament traits in Bos indicus crossbreds. Cow temperament was assessed from 1 to 5 indicating increasing levels of aggressiveness of cows (937 cows and 4,337 parturitions) from 2005 to 2022. Estimates of heritability and repeatability were 0.12 ± 0.024 and 0.24 ± 0.018. The estimates of proportion of phenotypic variance were 0.13 ± 0.019 and 0.02 ± 0.011 for permanent and maternal permanent environmental components, respectively. Estimates of heritability for maximum lifetime temperament score and proportions of temperament scores >1 were 0.18 ± 0.07 and 0.13 ± 0.072. Within cycles (generations), 2-yr-old cows had lower temperament score means than cows in most other age categories. There were low to moderate positive estimates of unadjusted correlation coefficients (r = 0.22 to 0.29; P < 0.05) of unadjusted temperament score with temperament measured on the same females when they were 8 mo old. There were low to moderate positive estimates of correlation coefficients (r = 0.09 to 0.37; P < 0.05) of unadjusted temperament score with calving rate, weaning rate, weaning weight per cow exposed, and weaning weight per 454kg cow weight at weaning. Cows with the lowest temperament score had lower (P < 0.05) calving and weaning rate than cows in other temperament categories. Within 3 of 5 cycles, cows with the lowest temperament score (totally docile) had lower (P < 0.05) weaning weight per cow exposed than cows in other temperament categories. There were 2 SNP on BTA 4 associated with maximum lifetime temperament score (FDR < 0.05). The non-genetic influence of a cow's mother was documented in her own temperament measured at the time of calving; this may be a consequence of learned behavior. Less aggressiveness displayed by cows at the time of calving may be accompanied by lower reproductive and maternal performance.

Advanced payment strategy for EOQ model regarding perishable product with maximum lifetime, customer return, preservation technology and partial backlogging

Advanced payment strategy for EOQ model regarding perishable product with maximum lifetime, customer return, preservation technology and partial backlogging

Simulation of excess lifetime cancer risk due to the presence of radon in groundwater in Wamba town of Wamba local government area, Nasarawa state, Nigeria

The measurements of Radon concentration in ten groundwater (4-wells and 6-boreholes) from Wamba town of Wamba Local Government Area of Nigeria had been carried out. The annual effective dose (AED) and the Excess Lifetime Cancer Risk (ELCR) due to ingestion of the groundwater was established to ascertain the risk outcome from the samples. Radon concentration was detected using RAD7. The minimum Radon concentration was 0.146 Bql-1 while the maximum was 0.474 Bql-1 with mean average of 0.3134 Bql-1 which are within the United States Environmental Protection Agencies (USEPA) 11.1 Bq/L recommendation. Moreso, the maximum and minimum Annual Effective Dose (AEDing) was 3.5×10^(-6) and 1.10×10^(-6) Sv/yr which are also within the 0.1 mSv/yr World Health Organization (WHO) recommendation, while the maximum and minimum Excess Lifetime Cancer Risk (ELCR) was 1.44×10^(-5) and 4.50×10^(-6) respectively. Cumulative probability simulation of the Excess Lifetime Cancer Risk (ELCR) was carried out using Oracle Crystal Ball software validated by 10 and 90% percentiles. Comparison of all the results with the European Union (EU)/World Health Organization (WHO) value of 500 Bq/L recommendation revealed that all the samples analyzed have Radon concentration below the recommended limit. The average mean Radon concentration in the ten locations from Wamba Town are within the recommended levels as confirmed by the simulation results. At 10% Probability, the highest risk was found in Event center (1.26×10^(-5)) while the lowest was found in the water sample collected from Angwan dalatu (1.05×10^(-6)) while at 90% probability the highest (1.62×10^(-5)) and lowest (1.37×10^(-6)) risk was found in the same Events center and Angwan dalatu. Though there is variation in the results based on locations which means that the concentration of Radon gas depends on the geological nature of the bedrock and generally increases with the uranium concentration in the local geology. The Excess Lifetime Cancer Risk (ELCR) dose results are far lower than the UNSCEAR (United Nations Scientific Committee on the Effects of Atomic Radiations) recommended maximum contamination level of 0.003875. Therefore, no indication of any likelihood of cancer incidence as a result of waterborne radon within the studied community that may demand urgent intervention from radiological point of view.

Extension of nature's NIR-I chromophore into the NIR-II region.

The development of chromophores that absorb in the near-infrared (NIR) region beyond 1000 nm underpins numerous applications in medical and energy sciences, yet also presents substantial challenges to molecular design and chemical synthesis. Here, the core bacteriochlorin chromophore of nature's NIR absorbers, bacteriochlorophylls, has been adapted and tailored by annulation in an effort to achieve absorption in the NIR-II region. The resulting bacteriochlorin, Phen2,1-BC, contains two annulated naphthalene groups spanning meso,β-positions of the bacteriochlorin and the 1,2-positions of the naphthalene. Phen2,1-BC was prepared via a new synthetic route. Phen2,1-BC is an isomer of previously examined Phen-BC, which differs only in attachment via the 1,8-positions of the naphthalene. Despite identical π-systems, the two bacteriochlorins have distinct spectroscopic and photophysical features. Phen-BC has long-wavelength absorption maximum (912 nm), oscillator strength (1.0), and S1 excited-state lifetime (150 ps) much different than Phen2,1-BC (1292 nm, 0.23, and 0.4 ps, respectively). These two molecules and an analogue with intermediate characteristics bearing annulated phenyl rings have unexpected properties relative to those of non-annulated counterparts. Understanding the distinctions requires extending concepts beyond the four-orbital-model description of tetrapyrrole spectroscopic features. In particular, a reduction in symmetry resulting from annulation results in electronic mixing of x- and y-polarized transitions/states, as well as vibronic coupling that together reduce oscillator strength of the long-wavelength absorption manifold and shorten the S1 excited-state lifetime. Collectively, the results suggest a heuristic for the molecular design of tetrapyrrole chromophores for deep penetration into the relatively unutilized NIR-II region.

(Invited) Crosscutting Materials Innovation for Transformational Chemical and Electrochemical Energy Conversion Technologies—Solid Oxide Cells

The Solid Oxide Cell (SOC) primarily operated as Solid Oxide Fuel Cell (SOFC) converts the chemical energy of a fuel such as hydrogen directly into electricity with very high efficiencies. Reverse operation of the exact same SOCs—as Solid Oxide Electrolysis Cells (SOEC) converts electrical energy into chemical energy by using the electricity to split chemical molecules such as steam, carbon dioxide or mixtures of both into hydrogen, carbon monoxide or mixtures of both respectively.The SOC is basically a gas-tight and oxide-ion conducting solid electrolyte, sandwiched between porous oxide ion – and electron-conducting electrode materials—the oxygen electrode and the fuel electrode where the electrochemical conversions occur.Irrespective of operation mode, the choice of SOC materials and processing routes generally aim for maximum performance and lifetime at chosen conversion rate and efficiency at nominal operation. This is as much as the technology can intrinsically offer and by far not enough to guarantee either profitable production of electricity or chemicals hydrogen, carbon monoxide or both. Ultimately the materials and manufacturing costs of the cell, stack, module, and system play a key role in the involved invest. Generally, operation costs such as cost of natural gas or electricity as well as maintenance costs are much more significant in determining the profitability of the technology than the investment costs. These technology-independent factors can in turn orientate the technologist to optimize the cell for either for maximum efficiency or conversion rate capability.In this talk we will discuss specific SOC materials such as doped zirconia, doped ceria, manganates, cobaltites, and titanates. Intrinsic limitations and advantages with respect to performance, durability and costs; how they are withstanding the test of time and the ever decreasing operation temperature from micro/nano structuration, infiltration and exsolution of electrocatalysts through switching of cell supports. We will give a perspective on the dependency of cell material choices based on technology use cases and boundary conditions Figure 1