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The high-speed permanent magnet motor has been widely used in the industrial field because of its high-power density, fast dynamic response, and wide speed range. High efficiency and stable operation are the premises for the high-speed permanent magnet motor to exert its advantages. Firstly, this article analyzes the problems existing in the drive technology of high-speed permanent magnet motors from three aspects: current harmonics, rotor position detection, and low carrier ratios. Aiming to address the above problems, the status of the latest research is summarized from the aspects of harmonic suppression, position sensorless, and control strategies. In addition, future research trends for high-speed permanent magnet motors are discussed. [ABSTRACT FROM AUTHOR]

Background: Gut microbes are important regulators of host health and can also function as disease indicators. Lactiplantibacilllus plantarum(L. plantarum)used as express and delivery vaccines for mucosal immunity have been shown to activate specific immune responses in numerous studies. Results: The interaction between recombinant L. plantarum and the gut microbiota was investigated in this study. The results indicated a change in the amount of gut OTU by recombinant L. plantarum. Recombinant L. plantarum dramatically boosted the species diversity of gut bacteria based on the Shannon-Wiener index. Beta diversity analysis showed that microbial structure was changed by recombinant L. plantarum. Furthermore, recombinant NC8 L. plantarum expressing a fusion between the P14.5 protein of the African swine fever virus and IL-33 enhanced the functions of gut bacteria in metabolism and immune regulation. Increased levels of IgG and IgG1 in serum and sIgA in feces, as well as enrichment of CD4+ T cells and IgA+ B cells, indicated that the gut microbiota exerted an immunomodulatory role when mediated by recombinant L. plantarum. Conclusions: These results revealed that recombinant L. plantarum exerted its potential role in the gut microbiota and gut immunity.These fndings contribute to a broader understanding and utilization of L. plantarum bacteria in various therapeutic applications. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is traditionally considered as a brain disorder featured by amyloid-β (Aβ) deposition. The current study on whether pathological changes of AD extend to the enteric nervous system (ENS) is still in its infancy. In this study, we found enteric Aβ deposition, intestinal dysfunction, and colonic inflammation in the young APP/PS1 mice. Moreover, these mice exhibited cholinergic and nitrergic signaling pathways damages and enteric neuronal loss. Our data show that Aβ42 treatment remarkably affected the gene expression of cultured myenteric neurons and the spontaneous contraction of intestinal smooth muscles. The intra-colon administration of Aβ42 induced ENS dysfunction, brain gliosis, and β-amyloidosis-like changes in the wild-type mice. Our results suggest that ENS mirrors the neuropathology observed in AD brains, and intestinal pathological changes may represent the prodromal events, which contribute to brain pathology in AD. In summary, our findings provide new opportunities for AD early diagnosis and prevention. [ABSTRACT FROM AUTHOR]

Short-term traffic flow prediction is an essential component of intelligent transportation systems. Shallow and deep pattern learning methods have been widely applied to short-term traffic flow prediction. However, shallow learning methods struggle with highly volatile data and models are usually constant-coefficient. On the other hand, deep learning methods require significant computational resources and time. In this paper, we propose a new adaptive fluctuation grey model for short-term traffic flow prediction. We combine the fractional differential equation and fractional accumulation generation operator, and expand the GM(1,1) model using trigonometric functions. Furthermore, we improve the Harris hawks algorithm by optimizing the distribution of the initial population with Cauchy mutation operator and introducing boundary constraint handling techniques to enhance the model parameter search capability. Finally, we apply the model to short-term traffic flow parameter prediction and compare it with the benchmark model. Results indicate that the new model shows better accuracy performance and better extraction of fluctuation information. [ABSTRACT FROM AUTHOR]

In the field of permanent magnet synchronous motor (PMSM) control, the sliding mode observer (SMO)-based sensorless control is widely used; however, the actual control input of the current observation function is asymmetric. It can lead to different velocities of the estimated currents approaching to the actual currents and will make the current and back EMF fluctuations more severe, and result in more skewed angle and speed estimates, especially at a lower carrier ratio. In response to the above problems, this paper proposes a variable weighting coefficient of an EMF-based sliding mode observer (VWC-SMO). Unlike the traditional sliding mode observers, the weighted sliding mode switching variables and their bandpass-filtered values are used as the input of the current observer in the VWC-SMO. Thereby, the asymmetry of the control input in the current observation function can be well-suppressed, and almost the same approaching velocity on the two sides of the sliding surface can be obtained. Therefore, chattering near the sliding surface can also be suppressed. The method is verified on a motor controller experimental platform, and the comparative results shows that the VWC-SMO can reduce chattering of the observed currents and mitigate back EMFs fluctuations and improve the dynamic and steady-state performance. [ABSTRACT FROM AUTHOR]

Low resolution Hall-effect sensors have been commonly applied in PMSM drives for the reason of cost and volume. Generally, rotor speed and position are estimated inaccurately due to the installation error of the sensors. The inaccurate position degrades the performance of current control and also increases torque ripples, which aggravates mechanical vibration and noise. An improved dual observer is proposed in this paper to suppress the impact of misplaced Hall-effect sensors and improve estimation accuracy. By a cascading dual Luenberger observer and combining feedback decoupling control, the low-order noises produced by the deviation of Hall signals are effectively suppressed. The effectiveness of the proposed method is verified by experimental results. [ABSTRACT FROM AUTHOR]

• Computational modeling of three-dimensional transient wear of thrust bearings in nuclear main pumps. • Positive and negative effects of the presence of scratches on tilting pad thrust bearings. • Effect of scratch wear on bearing lubrication characteristics during rotor start-up and shutdown. A tilting pad thrust bearing wear model based on computational fluid dynamics has been developed, and the wear model was verified and investigated experimentally based on a self-designed test rig. The results show that the presence of scratches results in an increase in oil film pressure, an elevation of the pad center temperature, and a decrease in the minimum oil film thickness. The number of scratches has a more pronounced effect on the lubrication performance of the pad. The test found that the presence of scratches can contain the abrasive chips, which has some positive significance. During the starting process, the pressure center of each ring gradually shifts towards the center of the pad, demonstrating a radial stretching phenomenon. With a further increase in speed, the overall oil film pressure decreases from the center to the periphery, and the influence of scratches on the oil film pressure distribution gradually decreases. [ABSTRACT FROM AUTHOR]

This article proposes a new brushless hybrid harmonic excitation scheme for wind generators, in which the excitation power is provided by the armature current and the stator harmonic control winding current together. In the generation of the field current, besides the main component produced by the excitation control winding equivalent magnetomotive force (MMF), one additional field current component is also produced by on-load armature high-order harmonic and tooth harmonic MMFs, which lead to a self-excitation loop existing in the excitation process. The additional field current component can compensate the flux weakening effect of the load current, which helps to maintain the output voltage characteristic stable in the case of load fluctuation. Besides, the power level of the excitation converter can be greatly reduced. Experimental results on prototype machines validate the effectiveness of the theoretical analyses and finite element analysis (FEA) results. [ABSTRACT FROM AUTHOR]

Artificial support system takes advantages of self-bearing capacity of surrounding rock mass in roadway support, which is one of the important supporting ideas in modern times. The implementation way of an artificial support system is worthy of deep investigation. In this study, an HLBR hypothesis was proposed with comprehensive consideration of mechanical properties of surrounding rock mass based on the reinforced arch theory and axial variation theory. A model of bearing structure in surrounding rock mass was constructed, and the stress state on the bearing structure was analyzed. It was believed that when the axial ratio (k) of this bearing structure is equal to the lateral stress factor (λ) (which is the optimal axial ratio), the tangential stress on the bearing boundary reaches the minimum and is in uniform distribution. At this moment, the roadway and the supporting structure can make good use of the self-carrying capacity of surrounding rock mass, which is conducive to lowering the stress distribution level of surrounding rock mass. According to prestress diffusion characteristics of bolt, some ways to achieve HLBR were proposed, which were the optimal axial ratio design, difference support and local grouting modification, and finally performance of the original support design in a belt roadway of the mining district IV of a mine in Shanxi Province. A new supporting scheme was provided according to the HLBR hypothesis. In addition, the FLAC3D strain-softening model was modified by C++, which was used to interpret the reasonability of the suggested supporting scheme. The proposed HLBR hypothesis discloses ways to use self-capacity of surrounding rock mass. This study provides a new idea for roadway sectional design and roadway support design, which are beneficial to maintaining the stability of surrounding rock mass in roadways. [ABSTRACT FROM AUTHOR]

Detecting salient objects in RGB-D images attracts more and more attention in recent years. It benefits from the widespread use of depth sensors and can be applied in the comprehensive understanding of RGB-D images. Existing models focus on double-stream networks which transfer from color stream to depth stream, but depth stream with one channel information cannot learn the same feature as color stream with three channels information even if HHA representation is adopted. In our works, RGB-D four-channels input is chosen, and meanwhile, progressive parallel spatial and channel attention mechanisms are performed to improve feature representation. Spatial and channel attention can pay more attention on partial positions and channels in the image which show higher response to salient objects. Both attentive features are optimized by attentive feature from higher layer, respectively, and parallel fed into recurrent convolutional layer to generate side-output saliency maps guided by saliency map from higher layer. Last multi-level saliency maps are fused together from multi-scale perspective. Experiments on benchmark datasets demonstrate that parallel attention mechanism and progressive optimization operation play an important role in improving the accuracy of salient object detection, and our model outperforms state-of-the-art models in evaluation matrices. [ABSTRACT FROM AUTHOR]

• The cooperative energy transfer was discussed in down-conversion (DC) materials. • The bi-functional films with anti-reflection and DC performance were prepared. • The relatively enhanced E ff was 6.74% for SSCs with the bi-functional film. • The mechanism of increasing SSCs perfomance with bi-functional film was discussed. To improve energy conversion efficiency (E ff) of silicon solar cells, luminescent down-conversion (DC) is an effective approach to adjust solar spectrum by converting ultraviolet light to visible and near-infrared light. In this paper, Tb3+- Yb3+ co-doped NaYF 4 phosphors (DCNPs) were successfully synthesized by a simple solvothermal method. It was confirmed from the strong photoluminescence excitation (PLE) and photoluminescence (PL) emission peaks that the energy transfer occured between Tb3+ and Yb3+ ions. The DCNPs were added in the SiO 2 sol-gel to prepare anti-reflection coatings with DC performance, enhancing the visible and near-infrared region transmittance which matched with the band gap of silicon. An optimized short-circuit current density (J sc) of 33.39 mA/cm2 and a relatively enhanced E ff of 6.74% were achieved in the silicon solar cells with the bi-functional film. These results indicated the availability of anti-reflection coating with DCNPs for improving energy conversion efficiency of silicon solar cells. [ABSTRACT FROM AUTHOR]

• Hierarchical structure made of IP with different sizes was obtained. • The hierarchical structure possessed a lowest average reflectance of 7.5%. • The underlying mechanism behind hierarchical structure formation was proposed. • 0.27% increase of E ff was made due to the presence of hierarchical structure. • Al-BSF c -Si solar cell with hierarchical structure showed a high E ff of 19.80%. The fabrication of silicon hierarchical structures with both superior light trapping and efficient carrier collection is significant for improving the efficiency of c -Si solar cells. Here, we present a simple method to fabricate a novel hierarchical structure composed of inverted pyramid (IP) with different sizes by varying nanostructure rebuilding (NSR) ratio ([NaF]:[H 2 O 2 ]) during NSR treatment of silicon nanostructures containing Ag nanoparticles (AgNPs), followed by a systematic investigation of the underlying mechanism behind the structure formation. The silicon nanostructure is obtained through a well-known Ag assisted chemical etching method. Independent of NSR ratio, large-size IP with AgNPs fixed at the vertex can always form by carefully modulating NSR duration. Interestingly, by changing NSR ratio to 1:2, 1:4 and 1:6, it is found that the dissolution rate of AgNPs at the vertex during NSR process rises accompanied with increasing the number of etching points by AgNPs redeposition on the IP side walls, forming hierarchical structures composed of IP with different sizes. Moreover, the weakening of masking effect of AgNPs is demonstrated with the increase of AgNPs dissolution, rendering the IP vertex from flat to sharp. By adopting the best hierarchical structure for light trapping, the corresponding Al back surface field (Al-BSF) c -Si cell can reach a high efficiency of 19.80% with a V oc of 644 mV, J sc of 38.77 mA/cm2, FF of 79.32%, which is 0.20% and 0.27% absolute higher than that of conventional random IP and micro pyramid (MP) based cell, respectively. [ABSTRACT FROM AUTHOR]

Quantum hypothesis testing has been greatly advanced for the binary discrimination of two states, or two channels. In this setting, we already know that quantum entanglement can be used to enhance the discrimination of two bosonic channels. Here, we remove the restriction of binary hypotheses and show that entangled photons can remarkably boost the discrimination of multiple bosonic channels. More precisely, we formulate a general problem of channel-position finding where the goal is to determine the position of a target channel among many background channels. We prove that, using entangled photons at the input and a generalized form of conditional nulling receiver at the output, we may outperform any classical strategy. Our results can be applied to enhance a range of technological tasks, including the optical readout of sparse classical data, the spectroscopic analysis of a frequency spectrum, and the determination of the direction of a target at fixed range. Quantum channel discrimination exploits quantum resources to improve hypothesis testing for binary bosonic channels. Here, the authors overcome the binary setting, showing quantum entanglement greatly enhances the discrimination performance for an arbitrary number of channels. [ABSTRACT FROM AUTHOR]

Porous silicon monoxide (p-SiO) is one of the most promising anode materials for lithium-ion batteries because it possesses high theoretical capacity and small volume expansion. Traditionally, SiO is prepared at 1200 °C, which restrains the application of SiO materials due to its high consumption of energy. Herein, a low-temperature synthesis process of p-SiO at 650 °C is developed from a controllable magnesiothermic reduction of porous silica. Compared with normally reduced solid silica (SiO 2 @SiO), p-SiO is fabricated more easily from porous SiO 2 due to the improved contact between SiO 2 and Mg atom. Moreover, high porosity of p-SiO facilitates the growth of carbon shell, making p-SiO@C with remarkable electrochemical properties. The reversible capacity for p-SiO@C (839.6 mA h g−1, at 500 mA g−1) is about two times that for SiO 2 @SiO@C (426.4 mA h g−1, at 500 mA g−1) after 110 cycles, and the synergetic properties of p-SiO@C further presents good cycling stability (777.1 mA h g−1, at 500 mA g−1 after 300 cycles) and excellent rate capability (977 mA h g−1, at 1000 mA g−1). The low-temperature fabrication of p-SiO followed by carbonization is promoting for practical application in high-performance Si-based lithium-ion battery. [ABSTRACT FROM AUTHOR]

The position and speed estimation performance of the sliding mode observer (SMO) for permanent magnet synchronous motor (PMSM) drives under low carrier ratio degrades, due to the inherent chattering and enlarged control delay. To improve estimation performance, this paper proposes a quasi-proportional-resonant (QPR) based adaptive observer to obtain back electromotive force with adaptive harmonics cancellation. In this observer, the QPR controller is employed to eliminate errors between the observed currents and the actual ones in the αβ reference frame, replacing sign function and low pass filter (LPF) of the SMO to cancel the chattering, and harmonics immune performance can also be achieved thanks to frequency selection characteristic of the QPR controller. Besides cancelling the chattering, the proposed observer can also eliminate phase shift produced by the LPF, since the QPR controller is a zero phase-shift amplifier at the resonant frequency. Comparative experiments are carried out in a 3-kW PMSM drive, and the results validate the effectiveness of the proposed adaptive position observer. [ABSTRACT FROM AUTHOR]

• Design and validation of a scaled-down tilting pad thrust bearing test system for nuclear main pumps. • Changes in oil film pressure and pad temperature due to loading forces on main pumps. • Changes in load and bearing lubrication properties during rotor start-stop processes. The lubrication performance of thrust bearings is essential for the efficient, economical, and safe operation of nuclear main pumps. In this paper, a test system for scaled-down tilting pad thrust bearings was designed and built, and the feasibility of the scaled-down scheme was verified. The test results show that: with the increase of loading force, the pressure and temperature at different measurement points gradually increase. The influence of lubricant temperature on oil film pressure under the same loading force is small. During the rotor start process, the oil film pressure shows a trend of first increasing and then gradually stabilizing, and the temperature of each pad center gradually increases. During the rotor stop process, the oil film pressure initially increases slightly and then drops sharply with the reduction of speed, while the temperature at the center of the pad gradually decreases and the rate of decrease gradually increases. [ABSTRACT FROM AUTHOR]

In order to reduce the chattering and phase shift, this article proposes an enhanced sliding mode observer (SMO) for the sensorless control of permanent magnet synchronous motor (PMSM). In the conventional SMO, a low-pass filter (LPF) is commonly employed to extract the back electromotive forces (EMFs) from the sliding mode switching function, which brings the phase shift and degrades the precision of position and speed estimations. In this article, a frequency-adaptive complex-coefficient filter (FACCF) is adopted to replace the LPF. Since the FACCF has no phase shift and amplitude attenuation at the central frequency, it can be used to extract the EMFs without distortion while the chattering can also be suppressed. For an easy parameter design, the normalized phase-locked loop is used to obtain accurately the position and speed estimations. The experiments are carried out on a 3-kW PMSM drive, and the results verify the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the additivity phenomenon in the quantum dynamic capacity region of a quantum channel for trading the resources of classical communication, quantum communication, and entanglement. Understanding such an additivity property is important if we want to optimally use a quantum channel for general communication purposes. However, in a lot of cases, the channel one will be using only has an additive single or double resource capacity region, and it is largely unknown if this could lead to a strictly superadditive double or triple resource capacity region, respectively. For example, if a channel has additive classical and quantum capacities, can the classical-quantum capacity region be strictly superadditive? In this paper, we answer such questions affirmatively. We give proof-of-principle requirements for these channels to exist. In most cases, we can provide an explicit construction of these quantum channels. The existence of these superadditive phenomena is surprising in contrast to the result that the additivity of both classical-entanglement and classical-quantum capacity regions imply the additivity of the triple resource capacity region for a given channel. [ABSTRACT FROM AUTHOR]

Abstract In this work, random inverted nanopyramids (INPs) are fabricated as light trapping structures on ultrathin c -Si through a simple and cost-effective wet chemical method, followed by a systematic investigation of the photo-capturing properties of INPs combining experiments and simulations. In comprehensive consideration of thickness loss and light trapping performance, random INPs are applied onto 45 μm ultrathin c -Si solar cell and a high short-current density (Jsc) (36.6 mA/cm2) and energy-conversion efficiency (17.0%) are achieved, which are 0.3 mA/cm2 and 0.13% respectively higher than that in micro pyramid textured one, and our electrical simulation also demonstrates that the advantages of INPs are more obvious on thinner c -Si compared with conventional micro pyramids. Finally, through electrical simulation, INPs textured 45 μm c -Si solar cell is expected to have a large improvement room for efficiency by controlling the front and rear surface recombination velocity. All the findings not only offer additional insight into the light-trapping mechanism in the random INPs but also provide controllable and efficient broadband light harvesters for next-generation cost effective flexible photovoltaics. Graphical abstract Image 1 Highlights • Size control of IPs from nano to microscale was achieved by varying MACE temperature. • Near-Yablonovitch limit absorptance was achieved on 45 μm c-Si by using random IPs. • 45 μm random IPs cell achieve 36.6 mA/cm2 current density and 17.0% efficiency. • A theoretical efficiency of 26.3% can be on 45 μm c-Si by optimization. [ABSTRACT FROM AUTHOR]

Oasis development relies on water supply and the supply mode can be divided into artesian piloting water (APW) mode and high-lift pumping water (HPW) mode. APW mode relies on gravity to retain and intercept water. HPW mode uses cascade pumping irrigation projects to transport water by up to 470 m, mainly serving extremely arid areas. A comprehensive analysis of the water-energy-food-ecology (WEFE) nexus to optimize water use management is conducive to the sustainable development of an oasis. Due to differences in water supply difficulty and cost, there are significant differences in socioeconomic development, water management, and drought adaptation between the APW and HPW oases. Taking the APW and HPW regions of Ningxia in the Yellow River Basin as the study areas, this study constructed a Bayesian network (BN) to quantify the causality and uncertainty in the WEFE nexus to analyze the development status and the evolving characteristics of the human-water relationships of the two regions. Scenario simulation based on BN quantified the impact and difference of management measures on the WEFE nexus in the two regions. During 2000–2020, as the APW region developed, agricultural water use decreased by 36%, showing great water-saving potential, while the development of the HPW region experienced water shortages. Excessive and inefficient agricultural water use is the main factor affecting the sustainability in both regions. Improving irrigation coefficient is the most effective way to reduce agricultural water use, and there is still a large adjustment space in agricultural water prices, channel lining rates and drip irrigation popularization areas to improve this coefficient. The adjustment of the planting structure will have great water-saving potential in the APW region, such as reducing rice area to 20,000 ha will save 5 × 108 m3 of water, but the potential is limited in the HPW area dominated by drought-resistant crops. In addition, improving wastewater treatment and ecological water use will effectively improve surface water quality and the ecological environment in the APW and HPW regions. [Display omitted] • We uniquely analyzed the water use status in the artesian piloting water area and high-lift pumping water area separately. • The Bayesian network effectively quantified the causality in the regional water-energy-food-ecology nexus. • Excessive and inefficient agricultural water use is the main factor affecting sustainable development. • Irrigation coefficient improvement is the most effective way to save water. • Adjusting the planting structure has different water-saving effects in the two areas. [ABSTRACT FROM AUTHOR]

Abstract Ultrathin c -Si solar cells with light trapping nanostructures attract tremendous research interest for their flexibility and high specific power density. However, the performance of the ultrathin c -Si solar cell is limited by a big light absorption loss due to the reduced thickness. Here, we report a novel ultrathin c -Si solar cell through the direct deposition of TiO 2 electron transporting layer and indium tin oxide (ITO) electrode modified with ultrathin low workfunction (WF) metal subsequently onto random inverted nanopyramids (INPs) texture. The random INPs are fabricated through the well-known two-step Ag assisted chemical etching method followed by a post nanostructure rebuilding process. The TiO 2 thickness, deposition temperature and metal layer thickness are changed to optimize cell performance. With the optimized parameters, a high short-current density (Jsc) (30.66 mA/cm2) and energy-conversion efficiency (11.36%) are achieved on random INPs based 45 μm ultrathin c -Si solar cell by choosing 2 nm Mg layer as the modifying ultrathin metal layer, which are 37.65% and 36.4% respectively higher than that in planar one. All the findings not only offer additional insight into the mechanism of TiO 2 electron transporting layer based ultrathin c -Si solar cell but also introduce a promising new approach for next-generation cost effective flexible photovoltaics. Graphical abstract Image 1 Highlights • TiO 2 electron transporting layer can separate carriers between c -Si and electrode. • Ultrathin metal with low work function is used to modify the work function of ITO. • Efficient light trapping on 45 μm c -Si is realized by inverted nanopyramids (INPs). • 11.36% efficiency is achieved on INPs based 45 μm c -Si cell by using ultrathin Mg. [ABSTRACT FROM AUTHOR]

Since challenges still exist in size control fabrication of inverted pyramids (IPs) on c -Si substrate, size difference of IPs among reported literatures still can not be explained reasonably. Here, formation mechanism of IPs from sub-micro scale to micro scale for light trapping on c -Si substrate is reported based on metal assisted chemical etching (MACE) temperature control for the first time. The formation of the IPs is realized through a mask-less Ag assisted wet chemical etching method followed by a post nanostructure rebuilding (NSR) process. It is found that the etching directions on (1 0 0) Si can be influenced by the MACE temperature due to the shrink of Ag nanoparticles at high MACE temperature, leaving behind few pore channels in the deepest region of black silicon layer as nucleation sites. Thus large IPs can be formed during the following NSR process. It is believed that the elucidation of the fundamental formation will speed up the fabrication of wafer-scale c -Si IPs for application in bulk and ultrathin c -Si solar cells. [ABSTRACT FROM AUTHOR]

Ultrathin c -Si solar cells (≤50 μm) are believed to be applied in military, aerospace and other special circumstances in the future due to their flexibility and high specific power density, and thus has attracted a great deal of research interest. However, until now, lacking fabrication means of high-quality ultrathin c -Si materials accompanied with their inefficient absorption of near-infrared light greatly limits their further application. In this work, we present a simple and novel method to realize rapid thinning and texturing of bulk c -Si at room temperature by varying the ρ ([HF]/([HF] + [H 2 O 2 ])) values during the one-step Cu-assisted chemical etching process, followed by a systematic investigation of the formation mechanism of the surface structures. It is found that the sizes of surface structures accompanied with the etching rate increase with increasing the ρ values from 40% to 95% during the double sided etching process, and a high etching rate of 29.6 µm/min is obtained under the ρ value of 95%. For rapid thinning and efficient absorption of near-infrared light, 45 µm c -Si solar cell with asymmetric front and back light trapping structures is rapidly fabricated by directly immersing as-sawn bulk c -Si substrate into the thinning (ρ = 95%) and texturing (ρ = 60%) solution successively for only a few minutes. A high short-current density (Jsc) (36.12 mA/cm 2 ) and energy-conversion efficiency (17.3%) are achieved, which are 1.09 mA/cm 2 and 0.4% higher respectively than that in 45 µm c -Si with flat back surface. Based on the absorption spectra, it is demonstrated that the 45 µm c -Si cell with our asymmetric structures yields a high theoretical Jsc of 42.47 mA/cm 2 , which nearly approaches the Yablonovitch limit of 42.56 mA/cm 2 . All the findings offer additional insight into the structure formation mechanism and pave a rapid and novel way for exploration of next-generation flexible photovoltaics. [ABSTRACT FROM AUTHOR]

The structure of heparin and heparan sulfate (Hep/HS) oligosaccharides, as determined by the length and the pattern of sulfation, acetylation, and uronic acid epimerization, dictates their biological function through modulating interactions with protein targets. But fine structural determination is a very challenging task due to the lability of the sulfate modifications and difficulties in separating isomeric HS chains. Previously, we reported a strategy for chemical derivatization involving permethylation, desulfation, and trideuteroperacetylation, combined with standard reverse phase LC-MS/MS that enables the structural sequencing for heparin/HS oligosaccharides of sizes up to dodecasaccharide by positionally replacing all sulfates with more stable trideuteroacetyl groups, allowing for robust MS/MS sequencing. However, isomeric oligosaccharides that contain both N-sulfation and N-acetylation become isotopomers after labeling, differing only in the sites of deuteration. This prevents chromatographic separation of these different mixed domain sequences post-derivatization, and makes sequencing by MS/MS difficult due to co-fragmentation of the isotopomers leading to chimeric product ion spectra. In order to improve chromatographic separation of mixed domain oligosaccharides, we have introduced a propionylation step in place of trideuteroacetylation for labeling of sites of sulfation. HS standard disaccharides have been used to evaluate the efficiency of this improved chemical derivatization. The results show that we can quantitatively replace sulfation with propionyl groups with the same high efficiency as the previously reported trideuteroacetylation. After derivatization, we demonstrate the ability to chromatographically separate two mixed domain tetrasaccharide isomers differing solely by the order of N-sulfation and N-acetylation, allowing for full sequencing of each by MS/MS. These results represent a marked improvement in the ability of our previously reported derivatization strategy to analyze complex mixtures of Hep/HS oligosaccharides without a decrease in sensitivity. [ABSTRACT FROM AUTHOR]

In this paper, a simple and cost-effective wet chemical method is presented to form quasi-inverted pyramids (QIP) on ultrathin c -Si for efficient light trapping and sufficient wettability. The QIP is fabricated by a well-known two-step Ag assisted chemical etching method followed by a post nanostructure rebuilding (NSR) process. The variation of [Ag + ] realizes the modulation of QIP size from sub-micro scale to micro scale. The comparable average absorptance value of 50 µm c -Si with double-sided QIP fabricated under 0.5 mM [Ag + ] (QIP-50) to that of 182 µm c -Si with double-sided conventional micro-scale pyramid in the spectral range of 300 – 1100 nm demonstrates an over 3.6-fold reduction in material usage. In comparison with nanopores-structured light-trapping configuration, the QIP-50 possesses much smaller specific surface area of ~2.39, which alleviates the surface recombination losses. After wet oxidation treatment, the water contact angle (WCA) of QIP-50 (35.73°) can achieve a comparable value to that of wet oxidized polished wafer (33.30°), demonstrating sufficient wettability of the QIP for high efficiency ultrathin c -Si/PEDOT:PSS hybrid solar cells. The finding of QIP with both efficient light trapping and superior wettability provides a new opportunity to improve the performance of ultrathin c -Si/PEDOT:PSS hybrid solar cells with a simple process at low cost. [ABSTRACT FROM AUTHOR]

This letter presents a fast open circuit diagnostic method for modular multilevel DC/DC converter (MMDDC), which is applied in super capacitor energy storage system. The proposed method is derived based on the analysis of submodule output characteristics under both normal and fault conditions. For MMDDC, different types of open circuit fault are reflected by the output voltage of submodule in certain operating modes, thus a simple and effective diagnostic method by the aid of a hardware circuit and a fast fault location algorithm is proposed. The hardware circuit is responsible for detecting submodule output voltage and its output result is transmitted to a processor to accomplish the final fault diagnosis along with drive signals. The proposed approach avoids complex mathematical operations and minimizes fault diagnostic time; moreover, it can achieve fault diagnosis under a wide super capacitor operating voltage range. Finally, the proposed diagnostic method is verified experimentally based on a laboratory-scale MMDDC energy storage prototype. [ABSTRACT FROM AUTHOR]

Aluminum-doped zinc oxide (AZO) has long been known as a promising low-cost alternative contact to conventional expensive indium-doped tin oxide (ITO) on silicon heterojunction (SHJ) solar cells. However, low fill factor (FF) of the AZO-based SHJ solar cell greatly limits the device performance as well as poses concerns about its commercial potential. Here, we present ITO/AZO/ITO stack as front contact on rear-junction SHJ cell, solving three challenges including sputter damage, bad contact and low conductivity simultaneously that are encountered on pure front AZO-based devices. Additionally, mechanism underlying the superior performance of ITO/AZO/ITO stack is unveiled by the analysis of phase, lifetime and electrical properties followed by Quokka3 simulation of vertical and lateral carrier transport. Then, successfully direct use of pure AZO at rear side of SHJ cell is demonstrated, though with a small increase of total series resistance (R s). Finally, a champion efficiency of 23.8% with >85% indium reduction is achieved on M2+ size cell by using ITO/AZO/ITO at n-side and pure AZO at p-side, showing a high average efficiency (η ∼ 23.6%) close to that of totally ITO-based references (η ∼ 23.7%). These findings provide a promising way to fabricate low-indium and high-efficiency SHJ cells with commercial potential. [Display omitted] • Silicon heterojunction solar cell with AZO contact was processed. • ITO/AZO/ITO front contact instead of pure AZO was designed to improve the FF. • Mechanism underlying the superiority of ITO/AZO/ITO stack was investigated. • Direct use of pure AZO at rear side of cell was demonstrated by Quokka3 simulation. • An efficiency of 23.8% with >85% indium reduction was achieved on M2+ size cell. [ABSTRACT FROM AUTHOR]

In this paper, flexible, robustly adhesive, surface smooth and oxide-resistive AgNWs/AZO composite transparent conductive films (TCFs) were prepared by spin-coating solvothermal derived AgNWs followed by magnetron sputtering AZO protective layer, after which, annealing treatment at 200 ℃ for 20 min was adopted to further increase the performance of the composite film. The samples were characterized by means of X-ray diffraction, Raman spectroscopy, scan electron microscopy, scanning probe microscope, UV–Vis spectrophotometer and four point probe. The best result of AgNWs/AZO composite films was the one with a transmittance of 85% at 550 nm accompanied with a low sheet resistance of 19 Ω/□ by controlling the spin-coating times fixed at three. The figure of merit for the composite TCFs was 10.4, which was larger than the value of 8.8 for commercial ITO film. These amazing results would render the AgNWs /AZO composite TCFs an ideal candidate to replace conventional ITO for its potential application in flexible devices including OPV and OLED. [ABSTRACT FROM AUTHOR]

This paper proposes a dual-space vector control scheme for the open-end winding permanent magnet synchronous motor (OEW-PMSM) drive fed by the dual inverter with a single dc supply. Potential zero-sequence current in the open-end winding drive system has to be considered since it causes circulating current in the winding and leads to high current stress of power semiconductor devices and high losses. Zero-sequence current in open-end winding ac motor drives is usually caused by the zero-sequence voltage, and therefore switching combinations which do not produce zero-sequence voltage are used to synthesize the reference voltage in existing methods. But even so, the zero-sequence voltage can also be produced by the dead time of the inverter. In order to suppress zero-sequence current in the OEW-PMSM drive, a dual-space vector control scheme is proposed and a novel dual-inverter space vector pulse width modulation (PWM) with the zero-sequence voltage reference is employed to regulate system zero-sequence voltage in this paper. Compared with existing dual inverter PWM strategies, the novel algorithm build a regulation mechanism for the zero-sequence voltage. The proposed method is compared with the conventional vector control by simulations and experiments, and the results shown that the proposed scheme can suppress zero-sequence current effectively. [ABSTRACT FROM AUTHOR]

This paper describes a brushless electrically excited synchronous machine with a distinctive rotor structure and additional harmonic field windings. Spatially distributed third harmonic magnetic fields will be created in the air gap by feeding the stator harmonic windings of a dc current. These harmonic MMFs will generate an induced voltage in the additional rotor harmonic coils, which can supply the field winding with a dc current after rectification. Based on this operation principle, distributions of harmonic windings and the stator harmonic magnetic fields are analyzed. The relationship between harmonic EMFs and rotor harmonic winding turns are studied. Mutual interference between the different magnetic fields and windings in the machine is discussed. The harmonic excitation fields and the air gap flux densities are then calculated by employing finite element methods, and the regulating characteristics of no-load EMF are analyzed and power losses of machine are discussed. Experimental results of one 1.0-kW prototype machine agree well with the theoretical analysis and finite element calculations, which helps to evaluate this type of synchronous machines having brushless electrical excitation. [ABSTRACT FROM AUTHOR]

In this paper, Cu 2 ZnSnS 4 (CZTS)/reduced graphene oxide (RGO) composite was obtained by a hydrothermal treatment of the mixture of CZTS and graphene oxide (GO). The samples were characterized by means of X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy and scan electron microscopy, thermal gravimetric analysis, and Brunauer–Emmmett–Teller (BET) test. The electrochemical performance of CZTS particles and CZTS/RGO composite used as supercapacitor electrodes was tested for the very first time. The electrochemical measurement demonstrated that the specific capacitance for CZTS/RGO in 3 M KOH aqueous electrolyte was as high as 591 F/g at a current density of 0.25 A/g which was four times larger than that of pure CZTS (138 F/g). Increasing the current density to 1 A/g, the specific capacitance of CZTS/RGO composite was kept as high as 248.5 F/g. After 1000 cycles, the capacity retention was still maintained at 80.6%. It was concluded that the high conductivity and large surface area of RGO resulted in the lower charge transfer and ion diffusion resistance in CZTS/RGO composite, which synergistically enhanced the capacitive performance of composite material. [ABSTRACT FROM AUTHOR]

The solid-liquid equilibrium and thermodynamic properties of FOX-7 in three binary mixed solvents (N-methyl pyrrolidone-water, N,N-dimethylacetamide-water and 1,4-Butyrolactone-water) are studied by focused beam reflectance measurement (FBRM) dynamic detection method and the solubility is predicted by conductor-like screening model for real solvents (COSMO-RS) under atmospheric pressure from 298.15 to 343.15 K. The results show that the solubility of FOX-7 increase with the increasing temperature and the mole fraction of W-methyl pyrrolidone, N,N-dimethylacetamide and 1,4-Butyrolactone. The solubility data can be well correlated by Apelblat, van't Hoff and Yaws equation. The data of hybrid thermodynamic parameters (including the hybrid enthalpy, entropy, and Gibbs energy) show that the dissolution process is endothermic, non-spontaneous and enthalpy driven. In addition, COSMO-RS can accurately predict the increasing trend of solubility with increasing of temperature and mole fraction of solvent. However, the COSMO-RS overestimates solubility in three binary solvents except for xNMP = 0.1575, the average mean squared quadratic error becomes larger with an increasing mole fraction of water. Solubility data and thermodynamic parameters can lay a foundation for the crystallization and spheroidization modification of FOX-7. [ABSTRACT FROM AUTHOR]

• The lattice structure construction method based on finite element mesh is proposed. • The optimization design method of heterogeneous lattice structure for additive manufacturing based on MIST method is proposed. • The lattice structure construction and optimization problem realized by using parametric language APDL. With the improvement of lightweight demand and the development of additive manufacturing technology, the manufacturing of complex lattice structure is made possible, and the construction of complex lattice structure is became more and more important. However, the existing commercial software will have the phenomenon of boundary cell damaged when realizing lattice structure for curve and surface graphics. Being aimed at the problem of boundary unit cell damage in the construction of large-scale lattice structure, this paper proposes a lattice structure construction method based on finite element mesh. Through the description of the parameterization, implementation principle and specific process of lattice structure, and finally compared with the existing commercial software inspire, the result is shown that this method is better than the lattice structure construction problem of commercial software, It also is solved the problem of boundary cell damage in the construction of large-scale lattice structure. In addition, many studies show that the optimized heterogeneous lattice structure is had better mechanical performance. In this paper, a method for optimizing the cross-sectional area of lattice members is proposed based on the mist method. In two-dimensional and three-dimensional numerical examples, the total volume strain energy of the lattice structure has been improved by more than 60% in theory. [ABSTRACT FROM AUTHOR]

This paper presents a new harmonic current excitation principle for a synchronous machine drive based on control of the spatial third harmonic MMF. Unlike existing harmonic excitation technologies, which utilize the third harmonic components of the rotor magnetic field, this brushless harmonic excitation principle is realized by injecting an ac single-phase current component or dc component into three-phase open stator windings thereby utilizing the resultant third harmonic spatial stator MMF component. This additional component generates either a stationary or time pulsating magnetic field which will induce voltages in a specially designed rotor winding. Through rectification, the induced voltage is used to supply dc current to the rotor excitation winding. To verify the aforementioned principle, theoretical analyses, magnetic field calculations by finite-element analysis and experiments with a 1.0-kW prototype machine have been performed and key influential factors have been investigated. The test results are shown to be consistent with the theoretical analysis, which validates the correctness of the theory. [ABSTRACT FROM PUBLISHER]

ZnO:Er, Li light conversion film has been successfully fabricated by sol–gel method. XRD measurement demonstrated the successful incorporation of Er 3+ and Li + into ZnO films. The as-grown film co-doped with 2% Er 3+ and 3% Li + is featured with a transmittance of about 86.8% in the range of 400–900 nm. Moreover, the film exhibits a visible light emission either being excited by 355 nm or 980 nm. Due to its relatively high transmittance characteristics and promising properties of converting both UV and NIR light to visible light, the developed film is considered to have a potential application in novel light conversion devices including solar cells. [ABSTRACT FROM AUTHOR]

The quantum ergordic theorem for a large class of quantum systems was proved by von Neumann [Z. Phys. 57, 30 (1929)] and again by Reimann [Phys. Rev. Lett. 101, 190403 (2008)] in a more practical and well-defined form. However, it is not clear whether the theorem applies to quantum chaotic systems. With a rigorous proof still elusive, we illustrate and verify this theorem for quantum chaotic systems with examples. Our numerical results show that a quantum chaotic system with an initial low-entropy state will dynamically relax to a high-entropy state and reach equilibrium. The quantum equilibrium state reached after dynamical relaxation bears a remarkable resemblance to the classical microcanonical ensemble. However, the fluctuations around equilibrium are distinct: The quantum fluctuations are exponential while the classical fluctuations are Gaussian. [ABSTRACT FROM AUTHOR]

Seeking efficient light trapping structures with both superior omnidirectional and electrical performance is always on the way for increasing electrical energy output of c -Si solar cell over a wide range of light incident angle (θ). Here, tile angle (δ) of quasi-periodic structure arrays is systematically modulated from 35.9° to 72.8° on diamond-wire-sawn (DWS) c -Si by a simple and cost-effective Cu and Ni co-assisted chemical etching way followed by a post treatment. Interestingly, compared with the conventional micro pyramid (MP), the optimized inverted pyramid (IP) like arrays with a δ of 64° possess both lower light reflectance and carrier recombination, leading to a corresponding solar cell with a higher efficiency (∼19.67%) than that of MP based counterpart (∼19.31%). Moreover, during the increase of θ, the external quantum efficiency (EQE) of 64° IP based cell drops much more slowly than that of MP based one by properly adjusting the relative position of the structure arrays and incident light, indicating its omnidirectional property. Simultaneously, a maximum relative enhancement of electrical output power approaching ∼5.8% in the θ range of −90°–90° is achieved on 64° IP based cell compared to the MP based one, the mechanism behind which is further explained by optical simulation. The above finds pave a new way to increase the electrical energy output in a simple and cost-effective way. • Tilt angle control of quasi-periodic IP was achieved by varying Cu and Ni ratio. • 0.36% absolute increase in solar cell efficiency was made based on 64° IP. • ∼5.8% relative increase of output power was achieved on 64° IP based cell. • Mechanism behind omnidirectional performance was explained by optical simulation. [ABSTRACT FROM AUTHOR]

Radars use time-of-flight measurement to infer the range to a distant target from its return's round-trip range delay. They typically transmit a high time-bandwidth product waveform and use pulse-compression reception to simultaneously achieve satisfactory range resolution and range accuracy under a peak transmitted-power constraint. Despite the many proposals for quantum radar, none have delineated the ultimate quantum limit on ranging accuracy. We derive that limit through continuous-time quantum analysis and show that quantum illumination ranging--a quantum pulse-compression radar that exploits the entanglement between a high time-bandwidth product transmitted signal pulse and and a high time-bandwidth product retained idler pulse--achieves that limit. We also show that quantum illumination ranging offers mean-squared range-delay accuracy that can be tens of dB better than that of a classical pulse-compression radar of the same pulse bandwidth and transmitted energy. [ABSTRACT FROM AUTHOR]

• ASFV MGF505-11R could inhibit cGAS-STING-mediated activation of IFN-β and ISRE promoters. • ASFV MGF505-11R specifically associated with STING. • ASFV MGF505-11R could degrade STING by the lysosomal, ubiquitin-proteasomen and autophagy pathways. • The C-terminal domain (1-360aa) of the ASFV SY18 MGF505-11R protein was main immunosuppressive function area. African swine fever (ASF) is an acute, hemorrhagic, and highly contact infectious disease caused by African swine fever virus (ASFV) infecting domestic pigs or wild boars, the mortality rate up to 100 %. Evasion of host innate immunity plays a vital role in the pathogenesis of ASFV. Studies have showed that the MGF505 genes involve in regulating the IFN-I response, but its mechanism of action remains poorly understood. In our present study, ASFV MGF505-11R inhibited IFN-β and ISRE activation induced by cGAS, IRF7, IRF3-5D, STING, IKKε and TBK1 accompanied by decreases of IFN-β, ISG15 and ISG56 mRNA transcription. ASFV MGF505-11R interacted with STING, degrading STING expression by the lysosomal, ubiquitin-proteasome and autophagy pathways. Moreover, ASFV MGF505-11R could inhibit the phosphorylation of TBK1 and IRF3 stimulated by cGAS/STING overexpression. Finally, the truncation mutation analysis indicated that the 1–191 aa and 182–360 aa of ASFV MGF505-11R could inhibit cGAS-STING-mediated activation of IFN-β promoters. In short, these results demonstrated that ASFV MGF505-11R involved in regulating the IFN-I response by negatively regulating the cGAS signaling pathway. In summary, this study preliminarily clarified the molecular mechanism of ASFV MGF505-11R gene antagonizing IFN-I-mediated antiviral, which will helpfully provide new strategies for treatment and prevention of ASF. [ABSTRACT FROM AUTHOR]

[Display omitted] • Porous SiO X was controllably produced by adding NaCl in the magnesiothermic process. • Increase of NaCl content produced O-rich SiO X @C with the high specific surface area. • 3D network of SiO X @C promoted fast diffusion of lithium-ion. • Graphite-like carbon coatings improved the electronic conductivity of SiO X @C. • Porous SiO X @C with rich oxygen led to superior electrochemical properties of LIB. Silicon suboxide (SiO X) is a promising anode material for lithium ion battery (LIB). However, oxygen-dependent SiO X poses a great impact on its cycling stability, which is difficult to controllably prepare. Additionally, the aggregation of nano-scale SiO X restricts the diffusion of lithium ion and structural stability during cycles. Herein, we realize the controllable preparation of porous SiO X /C sheets with various oxygen content and graphite-like carbon as anode materials of LIB. It is found that high oxygen content and a 3-dimensional network in SiO X /C can ensure high structural stability during cycles. As-prepared SiO X facilitates the growth of graphite-like carbon with high defect density, improving their electron and ion conductivity. As-prepared SiO X @C sheets deliver superior reversible capacity, cycling stability and rate performance (the second discharging capacity of 717.4 mAh g−1 at 100 mA g−1 with high initial Coulombic Efficiency of 64.08% is obtained; its capacity retention is as high as 100.44% against the second discharging capacity after 200 cycles; at a high current density of 2000 mA g−1, its reversible capacity still remains 389 mAh g−1). This work provides a novel and simple approach to controllably prepare disproportionated SiO X @C sheets with the 3-dimensional network as ultrastable SiO x -based anode materials of LIB for practical application. [ABSTRACT FROM AUTHOR]

It is well known that entanglement can benefit quantum information processing tasks. Quantum illumination, when first proposed, was surprising as the entanglement's benefit survived entanglement-breaking noise. Since then, many efforts have been devoted to study quantum sensing in noisy scenarios. The applicability of such schemes, however, is limited to a binary quantum hypothesis testing scenario. In terms of target detection, such schemes interrogate a single spatiotemporal resolution bin at a time, limiting the impact to radar detection. We resolve this binary-hypothesis limitation by proposing an entanglement-assisted quantum ranging protocol. By formulating a ranging task as a multiary hypothesis testing problem, we show that entanglement enables a 6-dB advantage in the error exponent against the optimal classical scheme. Moreover, the proposed ranging protocol can also be used to implement a pulse-position modulated entanglement-assisted communication protocol. Our ranging protocol reveals entanglement's potential in general quantum hypothesis testing tasks and paves the way toward a quantum-ranging radar with a provable quantum advantage. [ABSTRACT FROM AUTHOR]

Human activities have dramatically changed ecosystems. As an irreplaceable ecological barrier in western China, the Qilian Mountains (QLM) provide various ecosystem services for humans. To evaluate the changes in the intensity of human activities in the QLM and their impact on the ecosystem, the human footprint (HF) method was used to conduct a spatial dataset of human activity intensity. In our study, the NDVI was used to characterize the growth of vegetation, and six categories of human pressures were employed to create the HF map in the QLM for 2000–2015 at a 1-km scale. The results showed that the mean NDVI during the growing season showed a significant increasing trend over the entire QLM in the period 2000–2015, while the NDVI showed a significant declining trend of more than 70% concentrated in Qinghai. Human pressure throughout the QLM occurred at a low level during 2000–2015, being greater in the eastern region than the western region, while the Qinghai area had greater human pressure than the Gansu area. Due to the improvement in traffic facilities, tourism, overgrazing, and other illegal activities, grasslands, shrublands, forests, wetlands, and bare land were the vegetation types most affected by human activities (in decreasing order). As the core area of the QLM, the Qilian Mountains National Nature Reserve (NR) has effectively reduced the impact of human activities. However, due to the existence of many ecological historical debts caused by unreasonable management in the past, the national park established in 2017 is facing great challenges to achieve its goals. These data and results will provide reference and guidance for future protection and restoration of the QLM ecosystem. [ABSTRACT FROM AUTHOR]

A phase reference has been a standard requirement in continuous-variable quantum sensing and communication protocols. However, maintaining a phase reference is challenging due to environmental fluctuations, preventing quantum phenomena such as entanglement and coherence from being utilized in many scenarios. We show that quantum communication and entanglement-assisted communication without a phase reference are possible, when a short-time memory effect is present. The degradation in the communication rate of classical or quantum information transmission decreases inversely with the correlation time. Exact solutions of the quantum capacity and entanglement-assisted classical and quantum capacity for pure dephasing channels are derived, where non-Gaussian multipartite-entangled states show strict advantages over usual Gaussian sources. For thermal-loss dephasing channels, lower bounds of the capacities are derived. The lower bounds also extend to scenarios with fading effects in the channel. In addition, for entanglement-assisted communication, the lower bounds can be achieved by a simple phase-encoding scheme on two-mode squeezed vacuum sources, when the noise is large. [ABSTRACT FROM AUTHOR]

The significance of efficient antireflection over a wide light incident angle (θ) range without sacrificing surface passivation too much increases with the rapid development of photovoltaic industry. Here, worm-like pit (WLP)/inverted nanopyramid (INP) hierarchical structure was realized on c -Si by constructing INP on modified WLP with large lateral size. The INP was obtained through Ag assisted chemical etching based nanopore reshaping in nanostructure rebuilding (NSR) solution. The anti-reflectance performance especially the omnidirectional ability accompanied with the surface passivation effect of both micro pyramid (MP) and WLP/INP was systematically investigated and compared. Additionally, the hierarchical structure based c -Si cell with an efficiency up to 18.5% was achieved, which is 0.12% absolutely higher than that of MP based counterpart (18.38%). Most significantly, the WLP/INP based cell can always possess a higher electric output power over the θ range from −80° to 80° with a highest relative power enhancement of 3.0% compared with that of the MP based one. The above surface processing is facile and scalable, providing an alternative way for the obtaining of c -Si solar cells with large electrical energy output during practical application. • WLP/INP structure with 9.4% low reflectance is obtained by chemical etching. • Superior omnidirectional anti-reflectance ability on WLP/INP is demonstrated. • High efficiency of 18.50% is achieved on WLP/INP based solar cell. • A highest relative power rise of 3.0% is obtained on WLP/INP cell under various θ. [ABSTRACT FROM AUTHOR]

Quantum hypothesis testing is a central task in the entire field of quantum information theory. Understanding its ultimate limits will give insight into a wide range of quantum protocols and applications, from sensing to communication. Although the limits of hypothesis testing between quantum states have been completely clarified by the pioneering works of Helstrom in the 1970s, the more difficult problem of hypothesis testing with quantum channels, i.e., channel discrimination, is less understood. This is mainly due to the complications coming from the use of input entanglement and the possibility of employing adaptive strategies. In this Letter, we establish a lower limit for the ultimate error probability affecting the discrimination of an arbitrary number of quantum channels. We also show that this lower bound is achievable when the channels have certain symmetries. As an example, we apply our results to the problem of channel position finding, where the goal is to identify the location of a target channel among multiple background channels. In this general setting, we find that the use of entanglement offers a great advantage over strategies without entanglement, with nontrivial implications for data readout, target detection, and quantum spectroscopy. [ABSTRACT FROM AUTHOR]

• Size control of IPs from sub-micro to micro scale was achieved by varying ρ values. • 40 µm random INPs cell achieved 34.8 mA/cm2 current density and 17.44% efficiency. • Superior mechanical performance was proved on INPs based 40 µm c -Si. • Quasi-omnidirectional characteristics of INPs was found between 0° and 60°. • Quasi-omnidirectional performance of INPs was demonstrated by FDTD simulation. Flexible ultrathin c -Si (U-Si) solar cell is widely researched for its potential usage in places with various shapes and sizes. However, light incident angle (θ) varies with positions on the same cell accompanied with the easy crack of cell due to surface textures when the U-Si cell is under bending. Therefore, the fabrication of efficient antireflectance structures with both quasi-omnidirectional performance and superior mechanical performance is greatly required. Here, size control of inverted pyramid (IP) from nano to micro scale as antireflectance structures is realized by altering ρ ([HF]/[HF] + [H 2 O 2 ]) values at room temperature. The IP is obtained through the nanostructure rebuilding (NSR) treatment of Ag assisted chemical etched nanostructures. In comprehensive consideration of optical and mechanical performances, IP-60 (ρ = 60%) textured 40 µm U-Si cell is successfully fabricated with a short-current density of 34.8 mA/cm2 and energy-conversion efficiency of 17.44%, showing an 0.2 mA/cm2 and 0.13% improvement respectively compared with that of the micro pyramids (MP) based one. Moreover, the quasi-omnidirectional characteristics of IP-60 based 40 μm cell over 0–60° is demonstrated by experiment and simulation. The above finding makes it possible to broaden the application scope of U-Si cells into some new areas like stratospheric airships and wearable electronics. [ABSTRACT FROM AUTHOR]

A distributed sensing protocol uses a network of local sensing nodes to estimate a global feature of the network, such as a weighted average of locally detectable parameters. In the noiseless case, continuous-variable (CV) multipartite entanglement shared by the nodes can improve the precision of parameter estimation relative to the precision attainable by a network without shared entanglement; for an entangled protocol, the root mean square estimation error scales like 1/M with the number M of sensing nodes, the so-called Heisenberg scaling, while for protocols without entanglement, the error scales like . However, in the presence of loss and other noise sources, although multipartite entanglement still has some advantages for sensing displacements and phases, the scaling of the precision with M is less favorable. In this paper, we show that using CV error correction codes can enhance the robustness of sensing protocols against imperfections and reinstate Heisenberg scaling up to moderate values of M. Furthermore, while previous distributed sensing protocols could measure only a single quadrature, we construct a protocol in which both quadratures can be sensed simultaneously. Our work demonstrates the value of CV error correction codes in realistic sensing scenarios. [ABSTRACT FROM AUTHOR]

Since the clinical introduction of general anesthesia, its underlying mechanisms have not been fully elucidated. The ventral tegmental area (VTA) and parabrachial nucleus (PBN) play pivotal roles in the mechanisms underlying general anesthesia. However, whether dopaminergic (DA) projections from the VTA to the PBN play a role in mediating the effects of general anesthesia is unclear. We microinjected 6-hydroxydopamine into the PBN to damage tyrosine hydroxylase positive (TH+) neurons and found a prolonged recovery time from propofol anesthesia. We used calcium fiber photometry recording to explore the activity of TH + neurons in the PBN. Then, we used chemogenetic and optogenetic approaches either activate the VTADA-PBN pathway, shortening the propofol anesthesia emergence time, or inhibit this pathway, prolonging the emergence time. These data indicate the crucial involvement of TH + neurons in the PBN in regulating emergence from propofol anesthesia, while the activation of the VTADA-PBN pathway facilitates the emergence of propofol anesthesia. [ABSTRACT FROM AUTHOR]