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Recent studies indicate that CGG repeat expansions in LRP12, GIPC1, and NOTCH2NLC are associated with oculopharyngodistal myopathy (OPDM) types 1, 2, and 3, respectively. However, some clinicopathologically confirmed OPDM cases continue to have unknown genetic causes. Here, through a combination of long-read whole-genome sequencing (LRS), repeat-primed polymerase chain reaction (RP-PCR), and fluorescence amplicon length analysis PCR (AL-PCR), we found that a CGG repeat expansion in the 5' UTR of RILPL1 is associated with familial and simplex OPDM type 4 (OPDM4). The number of repeats ranged from 139 to 197. Methylation analysis indicates that the methylation levels in RILPL1 were unaltered in OPDM4 individuals. Analyses of muscle biopsies suggested that the expanded CGG repeat might be translated into a toxic poly-glycine protein that co-localizes with p62 in intranuclear inclusions. Moreover, analyses suggest that the toxic RNA gain-of-function effects also contributed to the pathogenesis of this disease. Intriguingly, all four types of OPDM have been found to be associated with the CGG repeat expansions located in 5' UTRs. This finding suggests that a common pathogenic mechanism, driven by the CGG repeat expansion, might underlie all cases of OPDM.

Background/purpose The scanning accuracy of intraoral scanners’ data collection plays a key role in the success of the final treatment. However, few studies start from scanning technology itself to directly evaluate it. The aim of this study was to evaluate the scanning accuracy of three intraoral scanners, to provide a reference for relevant research and clinical applications. Materials and methods Six types of resin models containing different numbers of crown-prepared abutments were three-dimensionally printed, and a model scanner, as well as three intraoral scanners, were used to digitally scan the six models. The obtained data were uploaded to three-dimensional reverse software for registration and comparison, and the accuracy of the models were analyzed. Results When scanning the six groups of models, the Omnicam outperformed both the TRIOS and iTero in terms of accuracy in all groups except the second molar group. The TRIOS and iTero scanners also exhibited decreased degrees of accuracy when scanning the long dental arch. The accuracy decreased as the scanning scope increased; however, the Omnicam scanner exhibited a relatively high degree of accuracy when scanning the three-unit fixed bridge and anterior areas. All scanners exhibited the lowest degree of accuracy when scanning the full-arch model. Certain deviations were observed, and the scanning areas at the incisal edges of the anterior teeth and end of the dental arch exhibited relatively large deviations. Conclusion With the model scanner data as reference, the scanning accuracy of the three scanners exhibited differences and certain deviations, which were within clinical tolerance.

This study was to examine the effect of leaning-forward posture (LFP) on gait parameters while using a rolling walker (RW). A cross-sectional study was conducted in which 23 older female adults were asked to walk with a RW on the GaitRite walkway in two posture situations: upright posture, and LFP caused by pushing the RW forward and then following the RW. The temporal and spatial gait parameters were obtained for data analysis. Results showed that compared with the upright posture, participants with LFP demonstrated significantly increased cadence, decreased velocity and gait cycle time (both swing and stance time decreased). Of spatial parameters, both step and stride length significantly decreased, but the base of support increased significantly. These indicate that LFP during ambulation with a RW could lead participants to a shuffling-like (many steps on short distance) gait pattern. They may help clinicians find proper rehabilitation interventions and appropriate patient education for this specific postural presentation.

The microstructure and mechanical properties of fine grained uranium prepared by equal channel angular pressing (ECAP) and subsequent intermediate heat treatment were investigated systematically by the confocal laser scanning microscope (CLSM), electron backscatter diffraction (EBSD) and split Hopkinson pressure bar (SHPB). The results show that the initial coarse grained uranium was refined from about 1000 to 6.5 μm prepared by ECAP at 3 passes and subsequent heat treatment, and the corresponding dynamic yield strength increased from 135 to 390 MPa. For the ECAPed uranium samples, the relationship between grain size and yield strength could be described by classical Hall–Petch relationship, and the fitting Hall–Petch relationship for the fine grained uranium samples prepared by ECAP was drawn.

Oculopharyngodistal myopathy (OPDM) is an adult-onset inherited neuromuscular disorder characterized by progressive ptosis, external ophthalmoplegia, and weakness of the masseter, facial, pharyngeal, and distal limb muscles. The myopathological features are presence of rimmed vacuoles (RVs) in the muscle fibers and myopathic changes of differing severity. Inheritance is variable, with either putative autosomal-dominant or autosomal-recessive pattern. Here, using a comprehensive strategy combining whole-genome sequencing (WGS), long-read whole-genome sequencing (LRS), linkage analysis, repeat-primed polymerase chain reaction (RP-PCR), and fluorescence amplicon length analysis polymerase chain reaction (AL-PCR), we identified an abnormal GGC repeat expansion in the 5′ UTR of GIPC1 in one out of four families and three sporadic case subjects from a Chinese OPDM cohort. Expanded GGC repeats were further confirmed as the cause of OPDM in an additional 2 out of 4 families and 6 out of 13 sporadic Chinese individuals with OPDM, as well as 7 out of 194 unrelated Japanese individuals with OPDM. Methylation, qRT-PCR, and western blot analysis indicated that GIPC1 mRNA levels were increased while protein levels were unaltered in OPDM-affected individuals. RNA sequencing indicated p53 signaling, vascular smooth muscle contraction, ubiquitin-mediated proteolysis, and ribosome pathways were involved in the pathogenic mechanisms of OPDM-affected individuals with GGC repeat expansion in GIPC1. This study provides further evidence that OPDM is associated with GGC repeat expansions in distinct genes and highly suggests that expanded GGC repeat units are essential in the pathogenesis of OPDM, regardless of the genes in which the expanded repeats are located.

The hydrogen evolution reaction (HER) represents one promising solution for energy and environmental sustainability. Nickel phosphide with various morphology has been recently investigated as promising earth abundant electrocatalysts for HER. Compared with three or two dimensional morphology, one dimensional (1D) nickel phosphide could provide larger specific surface area and hence improves the HER electrocatalytic performance. However, most reported 1D nickel phosphides show a small length-to-diameter ratio (less than 50). Herein, ultrahigh length-to-diameter ratio Ni2P nanowires synthesized by one-step phosphorization-sulfuration treatment are reported for the first time. The as-prepared nanowires have extremely high length to diameter ratio which ranges from 500 to 1000. The formation mechanism of such morphology is illustrated by a systematic study of the morphology, microstructure and elementary distribution of the nanowire array cathode. The ultralong nanowire morphology clearly helps improve the HER performances, since the self-supported Ni2P nanowire array cathode exhibits outstanding HER electrocatalytic activity and long-term durability in all of the acidic, alkaline, and neutral conditions.

Geminiviruses are a large group of plant viruses that have been a serious threat to worldwide agriculture. Transcription of the virus-encoded genes is necessary for geminiviruses to complete their life cycle, but the host proteins which directly target geminivirus promoters for suppression of viral gene transcription remain to be identified. Using Beet severe curly top virus (BSCTV) which causes severe plant symptoms as a system, we performed a yeast one-hybrid screening and identified ABA INSENSITIVE 5 (ABI5), a critical transcription factor in Abscisic acid (ABA) signaling transduction, as an interactor with the viral promoter. Further data showed that an ABA-responsive element in the viral promoter is necessary for its interaction with ABI5 and symptom development. Overexpression of ABI5 suppresses the transcription activity of the viral promoter and BSCTV infection in Nicotiana benthamiana and Arabidopsis; whilst depletion of ABI5 enhances the infection of BSCTV in Arabidopsis. Taken together, our study uncovered the function of ABI5 in the plant-virus interaction and will provide us with a new strategy to protect crops from geminivirus infection.

In this work, we report an experimental and theoretical study of the (130) twin system in the U-14.0 at.% Nb alloy using aberration-corrected TEM in combination with first-principles calculations. We clearly give the atomic structure of (130) twin and its twin boundary energy for the first time. We evidence that the widely used (130) twin system in pseudo-orthorhombic system is in fact the (101) twin system in the monoclinic crystal system. Through first-principles calculations, we also find that the local atomic structure of Nb significantly affects the twin boundary energy due to the depleted charge zone at Nb atom and charge-rich zone around Nb atom. These results may help us better understand the deformation mechanism in low-symmetry U metal and U-Nb alloys.

The microstructure changes and mechanical properties of dual-phase U-2Nb alloy subjected to shot peening treatment (SPT) were investigated. SPT induced severe plastic deformation in the U-2Nb alloy surface, and a gradient nanostructure was formed on the surface with the grain size ranging from nanocrystallization structure to coarse grains from the surface to the matrix. The results showed that both the α phase with an orthorhombic crystal structure and the γ phase with a body-centered cubic structure in the surface layer of the U-2Nb alloy were refined to nanocrystals with an average nanocrystallization structure size of 63 nm. Due to the concentration of stress at the α/γ interface and grain size effect, the refinement of the α phase matrix occurred before γ phase. Furthermore, dislocation slipping caused by deformation, rather than deformation twinning, played a key role in the grain refinement of U-2Nb alloy. Microhardness and tensile tests showed that both surface microhardness and tensile strength were improved after SPT.

Based on the theory of mixing enthalpy of i,j element pairs (ΔHij) and atomic-size difference δ, we designed a uranium-containing equiatomic UHfNbTi high-entropy alloy with a single-phase bcc structure. The alloy showed good room-temperature compressive plastic properties. They with stood at least 60% of compression strain without fracture. We investigated the effect of average valence electron concentration (VEC) on the mechanical properties of the alloy. Reducing the VEC number is expected to produce uranium-containing high-entropy alloys with high ductility.

To produce high-quality solar fuel, this work proposed a novel chemical looping in which a thermochemical cycle was hybridized with an electrochemical process. Specifically, sunlight was concentrated and split, short and medium solar spectrum was utilized for efficient PV-driven solid oxide electrolysis cell (SOEC), the rest spectrum was converted into heat to drive a three-step chemical looping steam reforming of methane (CLRM) cycle. The three-step CLRM consisted of reduction process with syngas production, oxidation process with hydrogen production, and reoxidation process of the oxygen carrier, respectively. By CLRM providing the reaction heat, the reactant of high-temperature steam and the reducing atmosphere required by cathode for SOEC, and simultaneously, SOEC providing high-temperature O2 for reoxidation process of CLRM, the thermochemical cycle can be well coupled with the electrochemical process and decrease the need for energy input. The design solar energy input to the novel cycle was supposed to be 55.6 MW, the solar-to-fuel efficiency can be expected to be 42.1%. This novel cycle allows the generation of a high-quality solar fuel with high efficiency and has a great potential in cost reduction.

The nanocatalysts of compound metal oxides ((La2CuO4)0.5(CNZ-1)0.5, denoted as LCO5-CNZ) composed of perovskite-like oxides La2CuO4 and CuO/ZnO/Al2O3 were prepared by co-precipitation and ball milling methods. The steam reforming of methanol (SRM) to H2 and CO2 over the nanocatalysts was experimentally studied at a molar ratio of 1.6 (H2O/methanol). The methanol solution catalyzed by LCO5-CNZ can be completely converted into H2, CO2 and a small amount of CO at the reaction temperature of 270 °C with a liquid hourly space velocity of 1.2 ml/(g·h). Simultaneously, under the same conditions, the catalysts of La2CuO4 and CuO/ZnO/Al2O3 were tested. Compared with the catalyst of pure La2CuO4, LCO5-CNZ showed higher methanol conversion rate and H2 yield. Compared with the conventional Cu-based catalyst of CuO/ZnO/Al2O3, LCO5-CNZ has both better CO selectivity and better H2 selectivity. It could be concluded that LCO5-CNZ with special structure has a significant improvement in catalyzing performance of SRM benefiting from the synergetic effect among perovskite-like La2CuO4 and Cu/Zn/Al oxides.

Oxide formation on surface of nitrogen-rich uranium nitride film/particles was investigated using X-ray photoelectron spectroscopy (XPS), auger electron spectroscopy (AES), aberration-corrected transmission electron microscopy (TEM), and high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) coupled with electron energy-loss spectroscopy (EELS). XPS and AES studies indicated that the oxidized layer on UN2-x film is ternary compound uranium oxynitride (UNxOy) in 5–10 nm thickness. TEM/HAADF-STEM and EELS studies revealed the UNxOy crystallizes in the FCC CaF2-type structure with the lattice parameter close to the CaF2-type UN2-x matrix. The work can provide further information to the oxidation mechanism of uranium nitride.

The determination of interstitial oxygen atom site in U2N3+xOy film could facilitate the understanding of the oxidation mechanism of α-U2N3 and the effect of U2N3+xOy on anti-oxidation. By comparing the similarities and variances between N K edge and O K edge electron energy loss spectra (EELS) for oxidized α-U2N3 and UO2, the present work looks at the local structure of nitrogen and oxygen atoms in U2N3+xOy film, identifying the most possible position of interstitial O atom.

To realize a short- and mid-term goal of sustainable development of solar fuel production, the possibility of effective hydrogen generation via methanol steam reforming at temperatures of 200 °C–300 °C inside a novel solar collector/reactor was experimentally demonstrated. With solar irradiation of 1000 W/m2, the solar collector-reactor achieved hydrogen generation rates up to 68.1 g/(m2·h), with solar-to-hydrogen efficiencies up to 41.3% and total energetic efficiencies (considering solar and fuel inputs) up to 76.6%, which is competitive with other solar fuel production technologies using high-temperature solar heat. Furthermore, the mechanism of upgrading the energy level of solar heat at 200 °C–300 °C was revealed based on the second law of thermodynamics and experimental results, where the catalyst was found to play a key role by decreasing the reaction temperature. The results obtained here indicate the possibility of utilizing the mid- and low-temperature solar heat for hydrogen production with high efficiency by upgrading the energy level of solar heat, and provide an enhancement to solar fuel production technologies with the development of this low-grade solar thermochemical technology in the near future.

Equal-channel angular pressing (ECAP) and mechanical machining were employed to introduce large plastic shear strain into bulk and the surface layer of a U-5.5wt.%Nb (U-5.5Nb) alloy, respectively. Applying ECAP, the U-5.5Nb alloy exhibited a single yield feature on the stress-strain curve in comparison to the “double yield” feature in the water quenched (WQ) counterpart. The difference is attributed to the characteristics of severe plastic deformation (SPD) structures obtained by ECAP. Mechanical machining resulted in a further severe microstructure refinement of the SPD surface layer with nano-grains/subgrains, which is accompanied with a dramatic increase of both the hardness and the elastic modulus of the surface layer. It is further proposed that the suppression of the shape memory effect (SME) in the nanostructured U-5.5Nb alloy may be responsible for the enhanced elastic modulus. The results of corrosion rate and pitting susceptibility showed a microstructure dependency, where the ECAP sample exhibited a better pitting resistance than that of the WQ counterpart.

Near-equiatomic, multi-component alloys with disordered solid solution phase (DSSP) are associated with outstanding performance in phase stability, mechanical properties and irradiation resistance, and may provide a feasible solution for developing novel uranium-based alloys with better fuel capacity. In this work, we build a machine learning (ML) model of disordered solid solution alloys (DSSAs) based on about 6000 known multicomponent alloys and several materials descriptors to efficiently predict the DSSAs formation ability. To fully optimize the ML model, we develop a multi-algorithm cross-verification approach in combination with the SHapley Additive exPlanations value (SHAP value). We find that the Delta S-C, Lambda, Phi(s), gamma and 1/Omega, corresponding to the former two Hume - Rothery (H - R) rules, are the most important materials descriptors affecting DSSAs formation ability. When the ML model is applied to the 375 uranium-bearing DSSAs, 190 of them are predicted to be the DSSAs never known before. 20 of these alloys were randomly synthesized and characterized. Our predictions are in-line with experiments with 3 inconsistent cases, suggesting that our strategy offers a fast and accurate way to predict novel multi-component alloys with high DSSAs formation ability. These findings shed considerable light on the mapping between the material descriptors and DSSAs formation ability.

Supercritical carbon dioxide (s-CO2) and the new generation molten salts can both be used as the heat transfer fluid in the solar supercritical carbon dioxide Brayton cycle. One of the main concerns in the design of solar s-CO2 Brayton cycle is that the working fluids need to meet the desired heat transfer coefficient to reach the high operating temperature, responding to the high concentrated heat flux. In this paper, to satisfy the SunShot Initiative’s goal of a 10 MWe solar s-CO2 Brayton cycle power plant, the receiver is designed to heat the s-CO2 and the NaCl–KCl–ZnCl2 eutectic salts from 500 oC to 750 oC to gain heat of 20 MWth. A tubular receiver made of pressureproof Haynes 230 is assumed. A one-dimensional computational heat transfer model is developed. The influences of receiver operating and structure parameters on the performance of the HTFs are evaluated. Finally, the outlet temperature, the heat gain, the solar field efficiency and the solar exergy efficiency for the s-CO2 and the new molten salts are compared. It is shown that both the fluids can reach the desired temperature and heat gain under special operating and structure parameters, but their relevant effectiveness to convert solar radiation into heat are different. The results obtained in this study are expected to provide references for the further development of the solar s-CO2 Brayton cycle technology.

Solar vapor generation utilizes ubiquitous solar energy to address the issue of global water shortage. However, its large-scale field deployment is greatly hampered by inefficient solar absorption, moderate evaporation efficiency and high cost. Here, we report a new hybrid photothermal membrane, named broadband plasmonic Cu2−xTe nanowire (bpCu2−xTe) membrane, for interfacial solar evaporation to produce freshwater from various water sources. The bpCu2−xTe membrane features excellent broadband solar absorption (~95.9%), high porosity and hydrophilicity, and low thermal conductivity (0.55 W/(m K)), which enables a water evaporation rate as high as 4.3 kg/(m2 h) with the evaporation efficiency of up to 96% under 3 kW/m2 solar irradiation. The evaporation performance of the present Cu2−xTe membrane can be maintained even after it recycles multiple times under various solar irradiance, indicating excellent durability and stability. Efficient solar desalination of seawater is further demonstrated with the bpCu2−xTe membrane to deliver drinkable water. The combination of scalable fabrication ability, low cost and excellent solar evaporation performance of the bpCu2−xTe membrane highlights the potential for seawater purification and desalination in field applications.

The objective of this study is to achieve a higher solar-to-electricity conversion efficiency through solar-fossil hybrid thermal power systems compared to a solar-only power plant. The study reveals the thermodynamic details for the improved solar-to-electricity efficiency in a solar hybrid power plant. A correlation was established to describe the main factors influencing the thermodynamic performances, including higher collector efficiency, higher turbine efficiency and upgraded energy level of the moderate-temperature solar heat. This proposed mechanism can be applied to effectively integrate solar and fossil-fired energy in a power system. The studies took typical fossil-fired power plants to hybridize with solar heat in three approaches: preheating the feed water before it entering the boiler for coal-fired system; heating for generation of saturate steam or superheated steam in gas-fired combined cycle. The results indicate that the moderate-temperature solar and fossil hybridization technology can provide a promising direction for efficient utilization of low-grade solar heat.

The hybridization of middle-temperature solar heat with traditional coal-fired power plants has profound and realistic implications for China. Most solar hybrid power plants, which differ from solar-only power plants, are not designed to include a thermal storage system to maintain system performance at nominal conditions during off-design solar radiation periods. Thus, a proper solar field size is an important design parameter. An excessively large field is partially useless under high solar irradiance, whereas a small field mainly reduces the work output and leads to the poor utilization of invested capital. This paper presents an economic optimization of the solar multiple (SM) for typical solar–coal parabolic trough plants with different unit scales (200–600 MW). The thermal performance for each solar hybrid power plant demonstrates that the methods to calculate the annual solar electricity produced with SM varies. Once the annual electric energy generation is identified, the levelized cost of energy (LCOE) and payback period (PP) for each case can be calculated. Thus, the optimized SM values yielding a minimum LCOE value or PP can be obtained. Furthermore, the influences of local solar radiation resources and turbine operation load conditions on the economic optimization of a system are estimated. Results indicate that the optimization of the solar field size is promising for the economic improvement of a solar–coal hybrid system. The results may also provide a theoretical reference for investors and government officials in designing a solar–coal hybrid project.

Physiological reflexes and anatomical barriers render traditional eye drop delivery inefficient. We previously reported that drug-loaded nanoparticles and microspheres prepared from montmorillonite and Eudragit polymers exhibited good sustained-release and lowered intraocular pressure. Here, we compared the performance of optimized formulations to select the most suitable formulation for glaucoma therapy. We found that the microspheres had much higher encapsulation efficiency and drug loading than nanoparticles. Moreover, cytocompatibility experiments demonstrated that nanoparticles showed more severe cytotoxicity than microspheres, probably due to their smaller particles, enhanced cell uptake, and intracellular solubility. Interestingly, the pre-corneal retention time of nanoparticles reflected a clear advantage over microspheres, while the duration of the pharmacological effect of nanoparticles was not as good as that of microspheres: compared with the nanoparticle depressurization duration of only 8 h, the microspheres continuously depressurized for 12 h. The slower release of the microspheres and its micro-interaction mechanism with the discontinuous mucin layer of the tear film led to the inconsistency between duration of pharmacodynamics and fluorescence ocular retention time. In summary, the lower cytotoxicity and longer pharmacological effect of microspheres indicate their potential advantages for glaucoma applications.

Deformation twins in cast uranium strained to 4.2% and 6.2% by quasi static compression were investigated using electron backscattered diffraction and transmission electron microscopy. Twin types of {130}, ‘{172}’, {112} and ‘{176}’ were observed in present experiment. All the operative twin variants in each twin type have the highest Schmid factor among the equivalent variants. Some {130} twins in cast uranium were inclined to disappear during subsequent loading through the re-twinning processes with Schmid factor values greater than 0.4. The ‘(−176)’ variant was identified by indexing the electron diffraction pattern combining with the stereographic projection analysis. Twin pairs of ‘(−176)’–‘(−17−2)’ occurred in the adjacent grains were well matched with the geometric compatibility factor value of 0.933.

Middle-temperature solar heat can be used to preheat feed water before it enters the boiler in a coal-fired power plant. Previous studies have shown that this approach can improve the performance of coal-fired power plants. The present study estimates the first solar–coal hybrid power plant in the Inner Mongolia Region. It will have a potential net solar power output of 10 MW on the basis of the operating data of a traditional 200 MW coal-fired power plant. Economic feasibility analysis is then performed on the solar–coal hybrid power plant. The appropriate feed-in tariff prices are provided on the basis of different financing scenarios, solar field cost, collector area size, and other conditions. The results obtained in this study are expected to provide suggestions for the further development of solar–coal hybrid technology.

Neutron generators, as an important neutron source, have been widely used in various fields. In order to improve their storage and service lifetime, the preparation of TiZrNi quasicrystal tritium target film with magnetron sputtering technology is explored in this paper. The nano-quasicrystal phase is found and confirmed for the first time in the film fabricated with the alloy target of Ti 34 Zr 49 Ni 17 and substrate deposition temperature of 450 °C. At a given composition of the TiZrNi alloy target, the formation of quasicrystal phase is very sensitive to the substrate temperature. Amorphous and fcc-(Ti,Zr) 2 Ni phase predominate in the TiZrNi films when the substrate temperatures are in the range of 100–400 °C and 500–600 °C, respectively. The compositions of the TiZrNi films prepared under different substrate temperatures are very close to each other and the values are about Ti 40 Zr 40 Ni 20 . The surface and cross-section morphologies show that the TiZrNi films are compact and dense with good adhesion between films and substrates. The TiZrNi quasicrystal film obtained in this work is hopeful to be applied to tritium target film of neutron generators.

The chemical composition and microstructure of main inclusions in U-0.79 wt%Ti alloy were investigated by Scanning Augur electron spectroscopy (SAM) and High resolution scanning transmission electron microscopy (HRSTEM). SAM analysis showed the predominant inclusion in U-0.79 wt%Ti alloy was in the form of titanium carbonitrides. HRSTEM showed the high resolution atom image of titanium carbonitride inclusion and further verified the phase structure of titanium carbonitride inclusion was Ti(C,N). The after-hydriding analysis showed that the hydrogen attack preferentially occurred around most of the Ti(C,N) inclusions in U-0.79 wt%Ti alloy, the initial hydride growth showed a parabolic-like kinetic behavior with a reaction order of 0.6. The inclusion-oxide interface can act as preferential transport channel for hydrogen to reach the metal.

The influence of diffusive Nb redistribution on the microstructure and Volta potential of U-5.5Nb alloys thermally aged at 400 °C for durations between 1 h and 100 h was investigated and their surfaces were examined post-corrosion using various microscopy techniques. The results demonstrated that Nb-depleted lamellae resulting from Nb redistribution have the lowest Volta potential in the microstructure and are extremely sensitive to pitting, as demonstrated by immersion experiments and potentiometric polarization tests. However, the pitting potential of the aged alloys (205.2 ± 3.9 mV) did not change with the content of Nb-depleted lamellae.

In this paper, an economic optimization of the solar multiple for the solar-coal hybrid systems was presented. The solar heat at approximately 300 °C was used to preheat the feed water before entering the boiler in the typical coal-fired power plants. Three different unit scale coal-fired power plants have been considered, with the different parameters in the power block and different solar field sizes. Thermal performance for each solar power plant has been featured, both at design and off-design conditions under the climatic conditions of Shizuishan City. The economic assessments were then performed. The costs and payback period of each configuration with different steam extraction replaced were compared, using the well-established cost-estimating methodology. The levelized cost of energy (LCOE) for each case is calculated, yielding a minimum LCOE value for a certain solar multiple value within the range considered.

The evolution of the oxide-overlayer's chemical nature on the surface of U–0.79 wt.%Ti alloy during vacuum annealing has been examined in situ by X-ray photoelectron spectroscopy (XPS). A specimen sheet of the alloy covered by oxide films is heated from room temperature to 700 °C in vacuum. It is found that the UO 2+ x outer oxide layer starts to be reduced to UO 2 at 200 °C. Between 300 and 400 °C, an oxycarbide (UO x C y ) layer is observed due to the reaction between UO 2 and carbon. Above 500 °C, UO x C y decomposes and the surface covered oxide layer starts to be reduced to the metallic state, meanwhile, a thermal driven segregation of Ti to the surface is also observed.

Attention has been directed toward hybridizing solar energy with fossil power plants since the 1990s to improve reliability and efficiency. Appropriate evaluation criteria were important in the design and optimization of solar–fossil hybrid systems. Two new criteria to evaluate the improved thermodynamic performances in a solar hybrid power plant were developed in this study. Correlations determined the main factors influencing the improved thermodynamic performances. The proposed criteria can be used to effectively integrate solar–coal hybridization systems. Typical 100 MW–1000 MW coal-fired power plants hybridized with solar heat at approximately 300 °C, which was used to preheat the feed water before entering the boiler, were evaluated using the criteria. The integration principle of solar–coal hybrid systems was also determined. The proposed evaluation criteria may be simple and reasonable for solar–coal hybrid systems with multi-energy input, thus directing system performance enhancement.

A higher solar-to-electricity conversion efficiency was one of the major advantages of the solar-fossil hybrid systems, compared to the solar-only power plants. In this paper, a new mechanism to reveal the reasons for the improved solar-to-electricity efficiency in a solar-hybrid power plant was given. A correlation was built to describe the main influencing factors of its thermodynamic performances, including higher collector efficiency, higher turbine internal efficiency and upgraded energy level of the mid and low-temperature solar heat. This proposed mechanism can be used to integrate solar–coal hybridization system effectively. A case study was taken as the typical 200 MW coal-fired power plant hybridized with solar heat at approximately 300 °C, where the solar heat was used to preheat the feed water before entering the boiler. Furthermore, simulation results of this mid and low-temperature solar-hybridization system was conducted to prove the proposed mechanism. It is expected that the theoretical values have a good agreement with the simulation ones. The results obtained indicate that why development of mid and low-temperature solar–coal hybridization technology may provide a promising direction to efficient utilization of low-grade solar thermal energy, and provide the direction to enhance system performances of this kind of solar–coal hybrid power plants.

Nanocatalysts of compound metal oxides (La2CuO4)x(CNZ-1)1−x (x = 0.3, 0.5, 0.7) were prepared. Steam reforming of methanol (SRM) over these nanocatalysts was experimentally studied at a H2O/methanol molar ratio of 1.6. The results showed that the methanol solution catalyzed by all catalysts synthesized in this work could be completely converted into H2, CO2 and a small amount of CO below a reaction temperature of 270 °C with a liquid hourly space velocity (LHSV) of 1.2 ml/(g·h). The catalysts of La2CuO4 and CuO/ZnO/Al2O3 were tested under the same operating conditions. Compared with La2CuO4, LCOx-CNZ showed better performance with a higher methanol conversion rate and H2 yield. Conversely LCO5-CNZ had better CO and H2 selectivity compared with CuO/ZnO/Al2O3. LCO3-CNZ showed good competitiveness in all four above aspects when operated at 150–270 °C. It could be concluded that LCOx-CNZ with special structures provided a significant improvement in catalytic performance of SRM benefiting from the synergistic effect among La2CuO4 and CuZnAl oxides. Thermodynamics analysis and experiments using a hybrid power generation system were applied with the above catalysts. Under direct normal irradiation at 915 W/m2 and a reaction temperature of 230 °C, LCO3-CNZ showed 9.7% higher H2 yield and 3.9% higher net solar power generation efficiency than did Cu/Zn/Al oxides.

This article proposed a hybrid power system combining mid-temperature solar heat and a coal-fired power plant for CO2 capture. In this system, solar heat at around 300 °C replaces the high-quality steam extractions of the Rankine cycle to heat the feed water, so the steam that was to be extracted can expand efficiently in the high-pressure turbines. In this hybrid system, the CO2 capture penalty is completely compensated for by the enhanced work output contributed by the solar heat. The annual solar field cost is reduced to 10.8 $/ton-CO2, compared to 25.8 $/ton-CO2 in a system with solar heat for direct solvent regeneration. Additionally, the mid-temperature solar heat is converted into work with an improved efficiency of 27%. Thus, this system offers a promising approach to reduce the CO2 capture penalty in CCS with attractive cost-effective utilization of mid-temperature solar heat.

An organic Rankine cycle (ORC) can be used to harness the wasted heat from an internal combustion engine. In this paper, the characteristics of a novel system combining a gasoline engine with a dual loop ORC which recovers the waste heat from both the exhaust and coolant systems is analyzed. A high temperature loop recovers the exhaust heat while a low temperature loop recovers both the residual high temperature loop heat and the coolant heat. The performance map of a gasoline engine is measured on an engine test bench and the heat quantities wasted by the exhaust and coolant systems are calculated and compared within the engine's entire operating region. Based on this data, the working parameters of a dual loop ORC are defined, and the performance of a combined engine-ORC system is evaluated across this entire region. The results show that the net power of the low temperature loop is higher than that of the high temperature loop, and the relative output power improves by from 14 to 16% in the peak effective thermal efficiency region to 50% in the small load region, and the absolute effective thermal efficiency increases by 3-6% throughout the engine's operating region.

Organic Rankine Cycle (ORC) could be used to recover low-grade waste heat. When a vehicle is running, the engine exhaust gas states have a wide range of variance. Defining the operational conditions of the ORC that achieve the maximum utilization of waste heat is important. In this paper the performance of different working fluids operating in specific regions was analyzed using a thermodynamic model built in Matlab together with REFPROP. Nine different pure organic working fluids were selected according to their physical and chemical properties. The results were compared in the regions when net power outputs were fixed at 10 kW. Safety levels and environmental impacts were also evaluated. The outcomes indicate that R11, R141b, R113 and R123 manifest slightly higher thermodynamic performances than the others; however, R245fa and R245ca are the most environment-friendly working fluids for engine waste heat-recovery applications. The optimal control principle of ORC under the transient process is discussed based on the analytical results.