SwePub - search: WFRF:(Xinyu Liu)

Enumeration	Reference	Cover	Find
1.	Beal, Jacob, et al. (author) Robust estimation of bacterial cell count from optical density 2020 In: Communications Biology. - : Springer Science and Business Media LLC. - 2399-3642. ; 3:1 Journal article (peer-reviewed)abstract Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data.
2.	Kristan, Matej, et al. (author) The Ninth Visual Object Tracking VOT2021 Challenge Results 2021 In: 2021 IEEE/CVF INTERNATIONAL CONFERENCE ON COMPUTER VISION WORKSHOPS (ICCVW 2021). - : IEEE COMPUTER SOC. - 9781665401913 ; , s. 2711-2738 Conference paper (peer-reviewed)abstract The Visual Object Tracking challenge VOT2021 is the ninth annual tracker benchmarking activity organized by the VOT initiative. Results of 71 trackers are presented; many are state-of-the-art trackers published at major computer vision conferences or in journals in recent years. The VOT2021 challenge was composed of four sub-challenges focusing on different tracking domains: (i) VOT-ST2021 challenge focused on short-term tracking in RGB, (ii) VOT-RT2021 challenge focused on "real-time" short-term tracking in RGB, (iii) VOT-LT2021 focused on long-term tracking, namely coping with target disappearance and reappearance and (iv) VOT-RGBD2021 challenge focused on long-term tracking in RGB and depth imagery. The VOT-ST2021 dataset was refreshed, while VOT-RGBD2021 introduces a training dataset and sequestered dataset for winner identification. The source code for most of the trackers, the datasets, the evaluation kit and the results along with the source code for most trackers are publicly available at the challenge website(1).
3.	Bi, Zhaozhao, et al. (author) Individual nanostructure optimization in donor and acceptor phases to achieve efficient quaternary organic solar cells 2019 In: Nano Energy. - : ELSEVIER. - 2211-2855 .- 2211-3282. ; 66 Journal article (peer-reviewed)abstract Fullerene derivative (PC71BM) and high crystallinity molecule (DR3TBDTT) are employed into PTB7-Th:FOIC based organic solar cells (OSCs) to cooperate an individual nanostructure optimized quaternary blend. PC71BM functions as molecular adjuster and phase modifier promoting FOIC forming "head-to-head" molecular packing and neutralizing the excessive FOIC crystallites. A multi-scale modified morphology is present thanks to the mixture of FOIC and PC71BM while DR3TBDTT disperses into PTB7-Th matrix to reinforce donors crystal-linity and enhance domain purity. Morphology characterization highlights the importance of individually optimizated nanostructures for donor and acceptor, which contributes to efficient hole and electron transport toward improved carrier mobilities and suppressed non-geminated recombination. Therefore, a power conversion efficiency of 13.51% is realized for a quaternary device which is 16% higher than the binary device (PTB7-Th:FOIC). This work demonstrates that utilizing quaternary strategy for simultaneous optimization of donor and acceptor phases is a feasible way to realize high efficient OSCs.
4.	Hu, Rukun, et al. (author) Design and assessment on a bottom-cut shape for latent heat storage tank filled with metal foam 2024 In: International Journal of Thermal Sciences. - 1290-0729. ; 197 Journal article (peer-reviewed)abstract The utilization of phase change materials (PCMs) holds tremendous potential of heat storage domain. The PCM's refractory at the latent heat thermal energy storage (LHTES) unit bottom hinders the heat storage efficiency, despite the significant improvement in thermal conductivity achieved through the addition of metal foam. This study employs numerical simulation to examine the impact of applying bottom cross-cut on PCM's spatial distribution in a horizontal LHTES unit. The manuscript analyzes parameters including melting fraction, complete melting time, Rayleigh number, natural convection heat transfer gain, melting phase interface, velocity and temperature distributions, and heat storage. The findings indicate that the proximity to the heating tube results in a reduction of solid volume at the LHTES unit bottom. A 0.6 bottom cross-cut ratio leads to an 18.84 % faster heat storage rate compared to a concentric-circle unit. Furthermore, a bottom cross-cut ratio of 0.5 enhances natural convection heat transfer gain by 3.28 times.
5.	Liu, Shaohui, et al. (author) Data-Driven Controlled Synthesis of Oriented Quasi-Spherical CsPbBr3 Perovskite Materials 2024 In: Angewandte Chemie International Edition. - : WILEY-V C H VERLAG GMBH. - 1433-7851 .- 1521-3773. ; 63:14 Journal article (peer-reviewed)abstract Controlled synthesis of lead-halide perovskite crystals is challenging yet attractive because of the pivotal role played by the crystal structure and growth conditions in regulating their properties. This study introduces data-driven strategies for the controlled synthesis of oriented quasi-spherical CsPbBr3, alongside an investigation into the synthesis mechanism. High-throughput rapid characterization of absorption spectra and color under ultraviolet illumination was conducted using 23 possible ligands for the synthesis of CsPbBr3 crystals. The links between the absorption spectra slope (difference in the absorbance at 400 nm and 450 nm divided by a wavelength interval of 50 nm) and crystal size were determined through statistical analysis of more than 100 related publications. Big data analysis and machine learning were employed to investigate a total of 688 absorption spectra and 652 color values, revealing correlations between synthesis parameters and properties. Ex situ characterization confirmed successful synthesis of oriented quasi-spherical CsPbBr3 perovskites using polyvinylpyrrolidone and Acacia. Density functional theory calculations highlighted strong adsorption of Acacia on the (110) facet of CsPbBr3. Optical properties of the oriented quasi-spherical perovskites prepared with these data-driven strategies were significantly improved. This study demonstrates that data-driven controlled synthesis facilitates morphology-controlled perovskites with excellent optical properties.
6.	Liu, Zhan, et al. (author) Effect of phase change heat storage tank with gradient fin structure on solar energy storage : A numerical study 2023 In: International Journal of Heat and Mass Transfer. - 0017-9310. ; 215 Journal article (peer-reviewed)abstract In this paper, the heat storage process of a latent heat thermal energy storage (LHTES) tank is studied numerically. A new type of gradient fin is added to the heat storage process in a latent heat storage tank to improve the heat transfer performance of the internal phase change material (PCM). The numerical model is verified by the experimental data. The influences of different structures on the melting rate, temperature distribution, velocity distribution, and maximum melting rate of PCM in LHTES tank are investigated, and the influence of natural convection on the energy storage system is further quantified. The results show that the melting time can be significantly reduced by 16.9% by using the four straight fins with gradient shape, and the melting time can be further reduced by 41.1% by reconstruction of the gradient fin position. The deformation in the opposite direction will slow down the melting speed and extend the melting time by more than 4.66 times. The convection criterion for judging the buoyancy convection of the melt in this paper shows that natural convection is dominant in both the upper and lower part of the melt. The closer the convection coefficient is to the overall heat transfer coefficient, the better the melting efficiency and energy efficiency will be.
7.	Wang, Hongwei, et al. (author) Porous fusion cage design via integrated global-local topology optimization and biomechanical analysis of performance 2020 In: Journal of The Mechanical Behavior of Biomedical Materials. - : Elsevier. - 1751-6161 .- 1878-0180. ; 112 Journal article (peer-reviewed)abstract Porous fusion cage is considered as a satisfactory substitute for solid fusion cage in transforaminal lumbar interbody fusion (TLIF) surgery due to its interconnectivity for bone ingrowth and appropriate stiffness reducing the risk of cage subsidence and stress shielding. This study presents an integrated global-local topology opti-mization approach to obtain porous titanium (Ti) fusion cage with desired biomechanical properties. Local topology optimizations are first conducted to obtain unit cells, and the numerical homogenization method is used to quantified the mechanical properties of unit cells. The preferred porous structure is then fabricated using selective laser melting, and its mechanical property is further verified via compression tests and numerical simulation. Afterward, global topology optimization is used for the global layout. The porous fusion cage obtained by the Boolean intersection between global structural layout and the porous structure decreases the solid volume of the cage by 9% for packing more bone grafts while achieving the same stiffness to conventional porous fusion cage. To eliminate stress concentration in the thin-wall structure, framework structures are constructed on the porous fusion cage. Although the alleviation of cage subsidence and stress shielding is decelerated, peak stress on the cage is significantly decreased, and more even stress distribution is demonstrated in the reinforced porous fusion cage. It promises long-term integrity and functions of the fusion cage. Overall, the reinforced porous fusion cage achieves a favorable mechanical performance and is a promising candidate for fusion surgery. The proposed optimization approach is promising for fusion cage design and can be extended to other orthopedic implant designs.
8.	Zhang, Xinyu, et al. (author) Pressure-induced zigzag phosphorus chain and superconductivity in boron monophosphide 2015 In: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 5 Journal article (peer-reviewed)abstract We report on the prediction of the zinc-blende structure BP into a novel C2/m phase from 113 to 208 GPa which possesses zigzag phosphorus chain structure, followed by another P4(2)/mnm structure above 208 GPa above using the particle-swarm search method. Strong electron-phonon coupling lambda in compressed BP is found, in particular for C2/m phase with the zigzag phosphorus chain, which has the highest lambda (0.56-0.61) value among them, leading to its high superconducting critical temperature T-c (9.4 K-11.5 K), which is comparable with the 4.5 Kto 13 Kvalue of black phosphorus phase I (orthorhombic, Cmca). This is the first system in the boron phosphides which shows superconductivity from the present theoretical calculations. Our results show that pressure-induced zigzag phosphorus chain in BP exhibit higher superconducting temperature T-C, opening a new route to search and design new superconductor materials with zigzag phosphorus chains.
9.	Cai, Weidong, et al. (author) Multicolor light emission and multifunctional applications in double perovskite-Cs 2 NaInCl 6 by Cu + /Sb 3+co-doping 2024 In: Chemical Engineering Journal. - : ELSEVIER SCIENCE SA. - 1385-8947 .- 1873-3212. ; 489 Journal article (peer-reviewed)abstract Halide double perovskites managed by metal doping approach can exhibit dual emission colors, which have been considered as promising multicolor luminescent materials. However, an independent and stable emission at yellow region is missing owing to limited doping candidates, hindering the further commercialization of multicolor luminescence applications in double perovskites. In this work, we successfully obtain stable multicolor emission with PLQE (photoluminescence quantum yield) as high as 78% through developing the CuI doping strategy in Sb-Cs2NaInCl6. By introducing a high CuI feed ratio in airtight autoclave to compete the oxidization effect, the oxidization of CuI into CuII (detrimental factor for high PLQE due to serious quenching effect) is largely suppressed. With changing the CuI feed ratio, at least four distinct emission colors ranging from blue, purple, pink to yellow can be realized via changing the excitation wavelength. Depending on tunable multicolor emission, we further demonstrate the promise of our co-doped double perovskites in anti-counterfeiting technology and multicolor lighting devices. Our results open the way for enriching the optical applications of double perovskites based on multicolor emission.
10.	Hart, Lucy J. F., et al. (author) Understanding the Role of Triplet-Triplet Annihilation in Non-Fullerene Acceptor Organic Solar Cells 2023 In: Advanced Energy Materials. - : WILEY-V C H VERLAG GMBH. - 1614-6832 .- 1614-6840. ; 13:36 Journal article (peer-reviewed)abstract Non-fullerene acceptors (NFAs) have enabled power conversion efficiencies exceeding 19% in organic solar cells (OSCs). However, the open-circuit voltage of OSCs remains low relative to their optical gap due to excessive non-radiative recombination, and this now limits performance. Here, an important aspect of OSC design is considered, namely management of the triplet exciton population formed after non-geminate charge recombination. By comparing the blends PM6:Y11 and PM6:Y6, it is shown that the greater crystallinity of the NFA domains in PM6:Y11 leads to a higher rate of triplet-triplet annihilation (TTA). This is attributed to the four times larger ground state dipole moment of Y11 versus Y6, which improves the long range NFA out-of-plane ordering. Since TTA converts a fraction of the non-emissive triplet states into bright singlet states, it has the potential to reduce non-radiative voltage losses. Through a kinetic analysis of the recombination processes under 1-Sun illumination, a framework is provided for determining the conditions under which TTA may improve OSC performance. If these could be satisfied, TTA has the potential to reduce non-radiative voltage losses by up to several tens of millivolts.
11.	Jokubavicius, Valdas, et al. (author) Growth optimization and applicability of thick on-axis SiC layers using sublimation epitaxy in vacuum 2016 In: Journal of Crystal Growth. - : Elsevier BV. - 0022-0248 .- 1873-5002. ; 448, s. 51-57 Journal article (peer-reviewed)abstract We demonstrate growth of thick SiC layers (100–200 µm) on nominally on-axis hexagonal substrates using sublimation epitaxy in vacuum (10−5 mbar) at temperatures varying from 1700 to 1975 °C with growth rates up to 270 µm/h and 70 µm/h for 6H- and 4H–SiC, respectively. The stability of hexagonal polytypes are related to process growth parameters and temperature profile which can be engineered using different thermal insulation materials and adjustment of the induction coil position with respect to the graphite crucible. We show that there exists a range of growth rates for which single-hexagonal polytype free of foreign polytype inclusions can be maintained. Further on, foreign polytypes like 3C–SiC can be stabilized by moving out of the process window. The applicability of on-axis growth is demonstrated by growing a 200 µm thick homoepitaxial 6H–SiC layer co-doped with nitrogen and boron in a range of 1018 cm−3 at a growth rate of about 270 µm/h. Such layers are of interest as a near UV to visible light converters in a monolithic white light emitting diode concept, where subsequent nitride-stack growth benefits from the on-axis orientation of the SiC layer.
12.	Jokubavicius, Valdas, et al. (author) Single Domain 3C-SiC Growth on Off-Oriented 4H-SiC Substrates 2015 In: Crystal Growth & Design. - : American Chemical Society (ACS). - 1528-7483 .- 1528-7505. ; 15:6, s. 2940-2947 Journal article (peer-reviewed)abstract We investigated the formation of structural defects in thick (∼1 mm) cubic silicon carbide (3C-SiC) layers grown on off-oriented 4H-SiC substrates via a lateral enlargement mechanism using different growth conditions. A two-step growth process based on this technique was developed, which provides a trade-off between the growth rate and the number of defects in the 3C-SiC layers. Moreover, we demonstrated that the two-step growth process combined with a geometrically controlled lateral enlargement mechanism allows the formation of a single 3C-SiC domain which enlarges and completely covers the substrate surface. High crystalline quality of the grown 3C-SiC layers is confirmed using high resolution X-ray diffraction and low temperature photoluminescence measurements.
13.	Li, Fangfei, et al. (author) Application and analysis of flip mechanism in the melting process of a triplex-tube latent heat energy storage unit 2023 In: Energy Reports. - : Elsevier BV. - 2352-4847. ; 9, s. 3989-4004 Journal article (peer-reviewed)abstract In order to improve the characteristics of uneven melting in the melting process of the horizontal latent heat energy storage system, the triplex-tube latent heat energy storage unit is taken as the research object, and the flip mechanism is applied to its melting process. Numerical simulation is used for the research, and the numerical model is verified by experimental data. The results show that under different dimensionless times, the melting performance of the unit can be significantly improved by a single flip. When the dimensionless time is 0.4576, it is found that the total melting time of the unit is reduced by 16.17 %, the average heat absorption rate is increased by 14.7 %, but the total heat energy absorption is reduced by 3.85 %. The results show that the addition of a flip can effectively shorten the melting time and increase the heat absorption rate, but it has a negative effect on the total heat absorption in one melting cycle. Moreover, through the comparison of dynamic flow rate, dynamic temperature response, and temperature interval, it is shown that the addition of flip effectively reduces the negative influence of the hard-to-melt zone on the melting performance of the unit during the melting process. The flip mechanism reduces the proportion of high-temperature phase change material in the melting process and makes the melting process more uniform.
14.	Liu, Xinyu, et al. (author) Vehicle trajectory prediction through manual setting and machine learning 2022 In: ISCTT 2022 - 7th International Conference on Information Science, Computer Technology and Transportation. ; , s. 612-616 Conference paper (peer-reviewed)abstract The prediction of vehicle trajectory is an important step in safe driving. The relative positions or speeds of vehicles affect the interactions between them, which in turn produce predictions of trajectories. Through the trajectory prediction of each vehicle to form a complete safe driving environment. This paper will be divided into two parts for vehicle track, namely manual setting and machine learning. The advantage of manual setting is that it is convenient to observe the characteristics and then make other vehicles follow the corresponding behaviour. However, the disadvantage is that the characteristics that can be observed are incomplete, which makes the experimental error relatively large. The advantage of machine learning is that through previous experience to make all vehicles change in the corresponding situation. Through previous experience to make all vehicles change in the corresponding situation. An effective extraction and addition of the original data is helpful to reduce the final error. Our code base can be found in https://github.com/RR30/CIS_multi_vehicle_prediction/tree/Xinyu.
15.	Liu, Yijia, et al. (author) Metasurface-Based Modulation With Enhanced Interference Resilience 2023 In: IEEE Communications Letters. - : Institute of Electrical and Electronics Engineers (IEEE). - 1089-7798 .- 1558-2558. ; 27:5, s. 1447-1451 Journal article (peer-reviewed)abstract Reconfigurable Intelligent Surfaces (RISs) have great potential for Internet of Things (IoT) applications due to their cost-effectiveness and energy-efficiency. However, under the application of RIS, current RIS systems cannot actively predict and avoid interference, as evolving interference signals can dynamically change their frequency bands. To address this issue, we develop a learning-based dynamic RIS spectrum access scheme to avoid interference and enhance wireless transmission reliability. An intelligent metasurface-based modulation (MM) is designed for generating and reflecting anti-interference radio-frequency signals. Specifically, a Dyna-Q algorithm is employed at the RIS controller to learn the frequency of interference signals, which is used to determine the frequency of the carrier signals. Experiments are conducted on the proposed RIS demo system to evaluate its anti-interference capability, and the results show that our scheme leads to an increase of at least 50% in the system throughput. These numerical results demonstrate the effectiveness of proposed scheme.
16.	Lu, Liu, et al. (author) High-performance formaldehyde prediction for indoor air quality assessment using time series deep learning 2024 In: Building Simulation. - : TSINGHUA UNIV PRESS. - 1996-3599 .- 1996-8744. Journal article (peer-reviewed)abstract Indoor air pollution resulting from volatile organic compounds (VOCs), especially formaldehyde, is a significant health concern needed to predict indoor formaldehyde concentration (Cf) in green intelligent building design. This study develops a thermal and wet coupling calculation model of porous fabric to account for the migration of formaldehyde molecules in indoor air and cotton, silk, and polyester fabric with heat flux in Harbin, Beijing, Xi'an, Shanghai, Guangzhou, and Kunming, China. The time-by-time indoor dry-bulb temperature (T), relative humidity (RH), and Cf, obtained from verified simulations, were collated and used as input data for the long short-term memory (LSTM) of the deep learning model that predicts indoor multivariate time series Cf from the secondary source effects of indoor fabrics (adsorption and release of formaldehyde). The trained LSTM model can be used to predict multivariate time series Cf at other emission times and locations. The LSTM-based model also predicted Cf with mean absolute percentage error (MAPE), symmetric mean absolute percentage error (SMAPE), mean absolute error (MAE), mean square error (MSE), and root mean square error (RMSE) that fell within 10%, 10%, 0.5, 0.5, and 0.8, respectively. In addition, the characteristics of the input dataset, model parameters, the prediction accuracy of different indoor fabrics, and the uncertainty of the data set are analyzed. The results show that the prediction accuracy of single data set input is higher than that of temperature and humidity input, and the prediction accuracy of LSTM is better than recurrent neural network (RNN). The method's feasibility was established, and the study provides theoretical support for guiding indoor air pollution control measures and ensuring human health and safety.
17.	Lu, Xiuzhen, et al. (author) Studies on Microstructure of Epoxy Molding Compound (EMC)-Leadframe Interface after Environmental Aging 2009 In: Proceedings of the 2009 International Conference on Electronic Packaging Technology & High Density Packaging (ICEPT-HDP). ; , s. 1051-1053 Conference paper (peer-reviewed)
18.	Ma, Quanbao, et al. (author) Boron-implanted 3C-SiC for intermediate band solar cells 2016 In: Silicon Carbide and Related Materials 2015. ; , s. 291-294 Conference paper (peer-reviewed)abstract Sublimation-grown 3C-SiC crystals were implanted with 2 atomic percent of boron ions at elevated temperature (400 °C) using multiple energies (100 to 575 keV) with a total dose of 8.5×1016 atoms/cm2. The samples were then annealed at 1400, 1500 and 1600 °C for 1h at each temperature. The buried boron box-like concentration profile can reach ~2×1021 cm-3 in the plateau region. The optical activity of the incorporated boron atoms was deduced from the evolution in absorption and emission spectra, indicating possible pathway for achieving an intermediate band behavior in boron doped 3C-SiC at sufficiently high dopant concentrations.
19.	Ma, Yue, et al. (author) Acid suppressants use and risk of atherosclerotic cardiovascular disease in middle-aged and older adults 2022 In: Atherosclerosis. - : Elsevier BV. - 0021-9150. ; 358, s. 47-54 Journal article (peer-reviewed)abstract Background and aims: Concerns regarding adverse events associated with the use of acid suppressants have increased. However, the impact of proton pump inhibitors (PPIs) and histamine‐2 receptor antagonists (H2RAs) on the risk of atherosclerotic cardiovascular disease (ASCVD) remains unknown. This study aimed to estimate the risk of ASCVD in association with the use of PPIs and H2RAs. Methods: This prospective cohort study included participants without cardiovascular diseases or anti-hypertensive treatment at baseline (2006–2010) in the UK Biobank. The outcomes were ASCVD and each subtype (coronary artery disease, myocardial infarction, peripheral artery disease, and ischemic stroke). The association was estimated by Cox proportional-hazards models. Results: Among 316,730 individuals (aged 50–88 years), during a median of 12.5 years of follow-up, we documented 13,503 (4.3%) incident ASCVD. Regular PPIs use was associated with a higher risk of ASCVD (HR: 1.16, 95% CI: 1.09–1.23) and every subtype of ASCVD. Among each type of PPIs, omeprazole (HR: 1.19, 95% CI: 1.11–1.28), lansoprazole (HR: 1.11, 95% CI: 1.02–1.22), and pantoprazole (HR: 1.40, 95% CI: 1.00–1.97) were associated with a higher risk of ASCVD. Stratification analysis showed that PPIs use was associated with a higher risk of ASCVD among individuals without indications of medications for PPIs. In addition, use of H2RAs was not related to the risk of ASCVD (HR: 0.97, 95% CI: 0.85–1.11). Conclusions: PPIs were associated with increased risk of ASCVD, particularly amongst participants without indications for medication. Our findings are of important practical significance and suggest that clinicians should be cautious in prophylactic use of PPIs.
20.	Meng, Jingxiang, et al. (author) Adaptive Differentiation in Seedling Traits in a Hybrid Pine Species Complex, Pinus densata and Its Parental Species, on the Tibetan Plateau 2015 In: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 10:3 Journal article (peer-reviewed)abstract Evidence from molecular genetics demonstrates that Pinus densata is a natural homoploid hybrid originating from the parent species Pinus tabuliformis and Pinus yunnanensis, and ecological selection may have played a role in the speciation of Pinus densata. However, data on differentiation in adaptive traits in the species complex are scarce. In this study, we performed a common garden test on 16 seedling traits to examine the differences between Pinus densata and its parental species in a high altitude environment. We found that among the 16 analyzed traits, 15 were significantly different among the species. Pinus tabuliformis had much earlier bud set and a relatively higher bud set ratio but poorer seedling growth, and Pinus yunnanensis had opposite responses for the same traits. Pinus densata had the greatest fitness with higher viability and growth rates than the parents. The relatively high genetic contribution of seedling traits among populations suggested that within each species the evolutionary background is complex. The correlations between the seedling traits of a population within a species and the environmental factors indicated different impacts of the environment on species evolution. The winter temperature is among the most important climate factors that affected the fitness of the three pine species. Our investigation provides empirical evidence on adaptive differentiation among this pine species complex at seedling stages.
21.	Sun, Jianwu, et al. (author) Solar driven energy conversion applications based on 3C-SiC 2016 In: 16th International Conference on Silicon Carbide and Related Materials, ICSCRM 2015. - : Trans Tech Publications Ltd. - 9783035710427 ; , s. 1028-1031 Conference paper (peer-reviewed)abstract There is a strong and growing worldwide research on exploring renewable energy resources. Solar energy is the most abundant, inexhaustible and clean energy source, but there are profound material challenges to capture, convert and store solar energy. In this work, we explore 3C-SiC as an attractive material towards solar-driven energy conversion applications: (i) Boron doped 3C-SiC as candidate for an intermediate band photovoltaic material, and (ii) 3C-SiC as a photoelectrode for solar-driven water splitting. Absorption spectrum of boron doped 3C-SiC shows a deep energy level at ~0.7 eV above the valence band edge. This indicates that boron doped 3C-SiC may be a good candidate as an intermediate band photovoltaic material, and that bulk like 3C-SiC can have sufficient quality to be a promising electrode for photoelectrochemical water splitting.
22.	Syväjärvi, Mikael, et al. (author) Cubic silicon carbide as a potential photovoltaic material 2016 In: Solar Energy Materials and Solar Cells. - : Elsevier. - 0927-0248 .- 1879-3398. ; 145, s. 104-108 Journal article (peer-reviewed)abstract In this work we present a significant advancement in cubic silicon carbide (3C-SiC) growth in terms of crystal quality and domain size, and indicate its potential use in photovoltaics. To date, the use of 3C-SiC for photovoltaics has not been considered due to the band gap of 2.3 eV being too large for conventional solar cells. Doping of 3C-SiC with boron introduces an energy level of 0.7 eV above the valence band. Such energy level may form an intermediate band (IB) in the band gap. This IB concept has been presented in the literature to act as an energy ladder that allows absorption of sub-bandgap photons to generate extra electron-hole pairs and increase the efficiency of a solar cell. The main challenge with this concept is to find a materials system that could realize such efficient photovoltaic behavior. The 3C-SiC bandgap and boron energy level fits nicely into the concept, but has not been explored for an IB behavior. For a long time crystalline 3C-SiC has been challenging to grow due to its metastable nature. The material mainly consists of a large number of small domains if the 3C polytype is maintained. In our work a crystal growth process was realized by a new approach that is a combination of initial nucleation and step-flow growth. In the process, the domains that form initially extend laterally to make larger 3C-SiC domains, thus leading to a pronounced improvement in crystalline quality of 3C-SiC. In order to explore the feasibility of IB in 3C-SiC using boron, we have explored two routes of introducing boron impurities; ion implantation on un-doped samples and epitaxial growth on un-doped samples using pre-doped source material. The results show that 3C-SiC doped with boron is an optically active material, and thus is interesting to be further studied for IB behavior. For the ion implanted samples the crystal quality was maintained even after high implantation doses and subsequent annealing. The same was true for the samples grown with pre-doped source material, even with a high concentration of boron impurities. We present optical emission and absorption properties of as-grown and boron implanted 3C-SiC. The low-temperature photoluminescence spectra indicate the formation of optically active deep boron centers, which may be utilized for achieving an IB behavior at sufficiently high dopant concentrations. We also discuss the potential of boron doped 3C-SiC base material in a broader range of applications, such as in photovoltaics, biomarkers and hydrogen generation by splitting water.
23.	Vinel, Claire, et al. (author) Comparative epigenetic analysis of tumour initiating cells and syngeneic EPSC-derived neural stem cells in glioblastoma 2021 In: Nature Communications. - : Springer Nature. - 2041-1723. ; 12:1 Journal article (peer-reviewed)abstract Epigenetic mechanisms which play an essential role in normal developmental processes, such as self-renewal and fate specification of neural stem cells (NSC) are also responsible for some of the changes in the glioblastoma (GBM) genome. Here we develop a strategy to compare the epigenetic and transcriptional make-up of primary GBM cells (GIC) with patient-matched expanded potential stem cell (EPSC)-derived NSC (iNSC). Using a comparative analysis of the transcriptome of syngeneic GIC/iNSC pairs, we identify a glycosaminoglycan (GAG)-mediated mechanism of recruitment of regulatory T cells (Tregs) in GBM. Integrated analysis of the transcriptome and DNA methylome of GBM cells identifies druggable target genes and patient-specific prediction of drug response in primary GIC cultures, which is validated in 3D and in vivo models. Taken together, we provide a proof of principle that this experimental pipeline has the potential to identify patient-specific disease mechanisms and druggable targets in GBM. The identification of patient-specific disease mechanisms and druggable targets is crucial for precision medicine in glioblastoma. Here, the authors show that comparing patients-matched glioma-initiating cells with neural stem cells enables the discovery of patient-specific mechanisms of disease and the identification of effective drugs
24.	Wang, Tao, et al. (author) Simultaneous Measurements of Dissolved Organic Carbon and Soil Respiration Reveal Reduced Soil Carbon Loss Under Nitrogen Addition in a Montane Forest 2022 In: Journal of Geophysical Research: Biogeosciences. - 2169-8953. ; 127:7 Journal article (peer-reviewed)abstract A major uncertainty in the estimation of soils acting as net carbon (C) sinks or sources stem from the effects of anthropogenic nitrogen (N) input on the balance between plant C input and soil C loss. In contrast to the generally observed increasing pattern of plant C input, the response of soil C loss to increased N deposition remains elusive, largely due to its large temporal variation. Here simultaneous measurements of two major soil C loss pathways, including dissolved organic carbon (DOC) leaching and soil respiration, were conducted for 5 and 3 yr, respectively, to assess the effects of N addition on soil C loss in an N-limited montane forest. The effects were seasonal, depth and N level dependent and the two pathways responded asynchronously to N addition. Significant decreases in DOC concentrations and fluxes in leachates from the organic layer were observed during autumn/winter under a high N addition rate (40 kg N/ha/yr). No significant impact of N addition on DOC concentrations or fluxes was observed for leachates from the mineral soil horizon. Biodegradability was low for DOC from both soil layers and was not consistently influenced by N addition. Soil respiration was significantly decreased under high N addition. Annual soil C loss (estimated by summing DOC leaching from the mineral horizon and soil respiration) showed that N addition reduced soil C loss consistently over years, implying that the forest soil is likely a C sink under excess N deposition, which should be confirmed with longer term monitoring.
25.	Wei, Xinyu, et al. (author) Holey Au-Ag alloy nanoplates with built-in hotspots for surface-enhanced Raman scattering 2016 In: Nanoscale. - : Royal Society of Chemistry (RSC). - 2040-3364 .- 2040-3372. ; 8:34, s. 15689-15695 Journal article (peer-reviewed)abstract Plasmonic noble metal nanocrystals with interior nanogaps have attracted great attention in surface-enhanced Raman scattering (SERS) applications due to the presence of built-in hotspots. Herein, we report a synthesis route to holey Au-Ag alloy nanoplates by controlled galvanic replacement with Ag nanoplates as the sacrificial template, a sulfite-coordinated Au(I) salt as the Au source, and polyvinylpyrrolidone (PVP) as the capping agent. PVP helps regulate the anisotropic growth of nanopores on the Ag nanoplates to afford a highly holey nanostructure, and the monovalent Au(I) salt plays a critical role in stabilizing these holey nanoplates by rapidly enriching Au in the alloy nanostructures. Numerical simulations and experimental results suggest that these holey Au-Ag alloy nanoplates possess enormous internal hotspots for high sensitivity in the SERS analysis, and high stability for excellent reliability of the analysis under many harsh conditions. We believe that this strategy is potentially applicable to the synthesis of many other types of plasmonic nanostructures with inherent nanogaps for many sensing and imaging applications.

Skapa referenser, mejla, bekava och länka

Permalink

Träfflista för sökning "WFRF:(Xinyu Liu) "

Refine your search

Year