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The BP@PVP Ionogel sensor with sensitive performance, robust interfacial adhesion and thermal tolerance should be provided a potential application in health-care monitoring or human-computer user interfaces.

Monometallic doping has proved its superiority in improving either permselectivity or H2 permeability of organosilica membranes for H2/CO2 separation, but it is still challenging to break the trade-off effect. Herein, we report a series of Pd-Nb bimetallic doped 1,2-bis(triethoxysilyl)ethane (Pd-Nb-BTESE, PNB) membranes with different metal doping routes for simultaneously improving H2 permeance and H2/CO2 permselectivity by the synergetic effects of Pd and Nb. The doped Pd can exist in the BTESE network as nanoparticles while the doped Nb is incorporated into BTESE network forming Nb-O-Si covalent bonds. The metal doping routes significantly influence the microstructure of PNB networks and gas separation performance of the PNB membranes. We found that the PNB membrane with Pd doping priority (PNB-Pd) exhibited the highest surface area and pore volume, comparing with Nb doping priority (PNB-Nb) or Pd-Nb simultaneous doping (PNB-PdNb). The PNB-Pd membrane could not only exhibit an excellent H2 permeance of ~ 10−6 mol·m−2·s−1·Pa−1 but also a high H2/CO2 permselectivity of 17.2. Our findings may provide novel insights into preparation of bimetallic doped organosilica membranes with excellent H2/CO2 separation performance.

1,2-bis(triethoxysilyl)ethane (BTESE)-derived membranes have proven thermal and hydrothermal stability and molecular sieving properties. However, BTESE-derived membranes still have low gas permselectivity due to their loose structure. Herein, we propose a novel strategy of co-polymerization using precursors of both BTESE and 1,2-bis(triethoxysilyl)methane (BTESM) to improve the gas permselectivity of BTESE-derived membranes. BTESM is introduced into BTESE network and the microstructure can be adjusted by different molar ratios of BTESE to BTESM. We find that, as the content of BTESM increase, H2 permeations of BTESE-BTESM membranes remain nearly constant, while the permeations of larger gases (CO2 and N2 etc.) exhibit a greatly decreased. The membrane with a molar ratio of BTESE:BTESM = 3:7 exhibits the highest H2/CO2 (11.3) and H2/N2 (26.8) permselectivity while having a relatively high H2 permeance (1.52 × 10−6 mol m2 s−1⋅Pa−1). Our findings may provide novel insights into preparation of co-polymerization organosilica membranes with excellent H2/CO2 and H2/N2 separation performance.

The photonic graphene in atoms not only has the typical photonic band structures but also exhibits controllable optical properties that are difficult to achieve in the natural graphene. Here, the evolution process of discrete diffraction patterns of a photonic graphene, which is constructed through a three-beam interference, is demonstrated experimentally in a 5S1/2 − 5P3/2 − 5D5/2 85Rb atomic vapor. The input probe beam experiences a periodic refractive index modulation when traveling through the atomic vapor, and the evolution of output patterns with honeycomb, hybrid-hexagonal, and hexagonal geometric profiles is obtained by controlling the experimental parameters of two-photon detuning and the power of the coupling field. Moreover, the Talbot images of such three kinds of periodic structure patterns at different propagating planes are observed experimentally. This work provides an ideal platform to investigate manipulation the propagation of light in artificial photonic lattices with tunable periodically varying refractive index.

Five non-real time satellite-based precipitation products (SPPs), including TMPA 3B42V7, CMORPH CRT, PERSIANN-CDR, GSMaP_MVK and GSMaP_Gauge, were evaluated over the Xijiang Basin. By driving XAJ model with each of the SPPs and gauge-based interpolation precipitation data to compare the hydrological responses at Wuzhou Station during the period of 2010–2017, this study also evaluated the applicability of these SPPs in rainfall-runoff simulation over the Xijaing Basin. The results showed that: (1) GSMaP_Gauge had highest accuracy, then are CMORPH CRT and TMPA 3B42V7, respectively, and finally are PERSIANN-CDR and GSMaP_MVK; (2) Among the five SPPs, CMORPH CRT, GSMaP_Gauge and TMPA-3B42 V7 have comparable performance in rainfall-runoff simulation, with NSE value lower than that generated by driving gauge-based interpolation precipitation and obviously higher than that of PERSIANN-CDR, and the uncorrected SPP, i.e., GSMaP_MVK, performs worst because of large systematic errors.

Beam splitting of high-order Gaussian (HOG) beams increases the channel capacity and improves the processing speed of the incoming information. Here a novel all-optical tunable multi-port HOG beam splitter under a periodic dielectric atomic structure is proposed and demonstrated. The original HOG beam is replicated in the output beams. A distinguishable five-port output beam is observed in the experiment, which is beneficial for high-speed optical communications. By tuning the optical properties of this periodic dielectric structure, the spatial position and intensity distribution of each output port are precisely controllable. The splitting ratio δ can be finely adjusted in the range 0 – 4.8. This work provides a new approach for multi-port HOG beam splitters and the basis for all-optical communication.

Optical vortex arrays (OVAs) containing multiple vortices have been in demand for multi-channel optical communications and multiple-particle trapping. In this Letter, an OVA with tunable intensity and spatial distribution was implemented all-optically in a two-dimensional (2D) electromagnetically induced atomic lattice (EIL). Such a square lattice is constructed by two orthogonal standing-wave fields in 85 R b vapor, resulting in the periodically modulated susceptibility of the probe beam based on electromagnetically induced transparency (EIT). An OVA with dark-hollow intensity distribution based on 2D EIL was observed in the experiment first. This work thus studied the nonlinear 2D EIL process both theoretically and experimentally, presenting, to the best of our knowledge, a novel method of dynamically obtaining and controlling an OVA and further promoting the construction of all-optical networks with atomic ensembles.

Pd-doped organosilica membranes were prepared by controlling calcination atmospheres (i.e. POS-Air, POS-N2, POS-H2, POS-H2/N2) to tailor their networks for improving their gas separation performance. This study shows that Pd (II) could be only maintained under non-reductive calcination atmosphere, while inert and reducing calcination atmosphere is more beneficial to maintain organosilica moieties in POS networks. POS-H2/N2 membrane showed the optimal H2 separation performance that its permselectivities for H2/CO2, H2/N2, H2/CH4 and H2/SF6 are 15.0, 96.7, 173.0 and 3400.0, respectively. Moreover, it is found that H2 molecules pass through the four membranes based on activated diffusion, while CO2 molecules permeation through POS-N2 and POS-Air membrane is dominated by surface diffusion. This work may provide insight into the understanding of the calcination atmosphere effect on gas separation performance of metal-doped organosilica membranes.

In this paper, we investigate a low earth orbit satellite (LEO SAT) and high altitude platform (HAP) integrated edge computing network to provide computing services for ground mobile devices (GMDs). We propose to minimize the weighted sum energy consumption via jointly optimizing the GMD association, precoding design, computation task assignment and computation resource allocation. To solve the nonconvex problem, we propose an algorithm that decomposes the optimization problem into four subproblems and solves each sub-problem iteratively. Specially, the GMD association subproblem is solved by quadratic transform based fractional programming (QTFP) and difference of convex function; the precoding design subproblem is obtained via QTFP and weighted minimum mean square (WMMSE) method; the computation task assignment is solved by the interior point method and the computation resource allocation is derived in closed form. The numerical results show that the proposed algorithms can solve the problems quite well and the energy consumption is maintained at a relative low level.

All-optical devices used to process optical signals without electro-optical conversion plays a vital role in the next generation of optical information processing systems. We demonstrate an efficient all-optical modulator that utilizes a periodic dielectric atomic lattice produced in a gas of 85Rb vapor. Four orders of diffraction patterns are observed when a probe laser is passed through the lattice. The frequency shift of the peak of each diffraction order can be tuned by adjusting the control laser power and two-photon detuning, enabling this device to be used as a multi-channel all-optical modulator. Both theoretical simulations and experimental results demonstrate that this modulator can operate over a frequency band extending from about 0 to 60 MHz. This work may pave the way for studying quantum information processing and quantum networking proposed in atomic ensembles.

Rural water supply projects are multi-faceted, wideranging and long-distances. Traditional automatic monitoring means are difficult to implement due to the predicaments in water supply operation and maintenance, resulting a series of problems including serious losses, high management costs, poor water supply guarantee rate and so on. This paper proposes a detection method based on the full chain coverage Internet of Things monitoring. Firstly, the massive real-time data are collected based on the monitoring system. The moving average algorithm is used for short- and medium-term data pre-processing. Then, triple exponential method is introduced for anomaly detection and warning of large flow leakage. The method proposed in this study has the characteristics of low computational complexity and high efficiency, and has strong anti-interference ability to noise at the same time.

The wettability of the coating used in controlled release fertilizers (CRFs) is a crucial parameter for the release behavior of nutrients. However, how to control the wettability of coating to tune nutrient release is a big challenge. Herein, the alkylamine-poly (tannic acid) (APTA) building blocks coatings with controlled wettability were prepared as coating materials for CRFs. Alkylamine (octadecylamine (ODA), hexadecylamine (HDA), dodecylamine (DDA), and hexylamine (HEA)) were applied for the modification of poly (tannic acid) (PTA) coating on the silicon wafer and urea surface. The wettability of coatings on silicon wafers were studied and nutrient release of APTA coated fertilizers were characterized in water and soil. The nitrogen nutrient and water vapor permeability coefficient of coatings were characterisized and the mathematical model for predicting the release of nutrients in soil. The alkyl chain length of alkylamine is demonstrated to play a crucial part in controlling the wettability. The rate of nutrient release increases in the order of ODA-PTA

Rydberg atoms have been widely investigated due to their large size, long radiative lifetime, huge polarizability and strong dipole-dipole interactions. The position information of Rydberg atoms provides more possibilities for quantum optics research, which can be obtained under the localization method. We study the behavior of three-dimensional (3D) Rydberg atom localization in a four-level configuration with the measurement of the spatial optical absorption. The atomic localization precision depends strongly on the detuning and Rabi frequency of the involved laser fields. A 100% probability of finding the Rydberg atom at a specific 3D position is achieved with precision of ∼0.031λ. This work demonstrates the possibility for achieving the 3D atom localization of the Rydberg atom in the experiment.

We propose a scheme for subwavelength three-dimensional (3D) Rydberg atom localization in a (V + Ξ)-type atomic system by spatial optical absorption microscopy. Position-dependent atom–field interaction allows atom position information to be obtained via measurement of the probe absorption. Some distinctive spatial localization patterns are discovered by adjusting the detuning and Rabi frequency of the laser fields. A 100% probability of finding the Rydberg atom at a specific position in 3D subwavelength space is achieved under appropriate conditions. This scheme may provide a novel approach for realizing high-precision 3D Rydberg atom localization in experiment.

In this work, high-performance palladium-niobium doped 1,2-bis(triethoxysilyl)ethane (Pd–Nb-BTESE) membranes were prepared for H2/CO2 separation by using the sol-gel method. Nb was first incorporated into the organosilica networks in the form of Nb–O–Si covalent bonds, while Pd nanoparticles were successfully embedded into the networks with size of 5–10 nm. Based on the synergetic effects of Pd–Nb doping, the as-prepared membranes showed more appropriate structures for H2/CO2 separation. By controlling the same doping amount of Nb and changing Pd doping contents (n (Pd): n(Si) = 0.05–0.4), we found that the Pd–Nb-BTESE membrane with higher Pd doping content showed higher H2/CO2 permselectivity and stronger H2 adsorption capacity. The H2/CO2 separation performance of all the prepared Pd–Nb-BTESE membranes surpass the upper bound 2008. The membrane with n (Pd): n (Si) of 0.4 showed a superior H2/CO2 permselectivity of 107 and a high H2 permeance of 1.12 × 10−7 mol m−2 s−1·Pa−1. Our findings provide novel insights into tailoring and functionalizing organosilica membranes through bimetallic doping for practical applications.

Electromagnetically induced grating (EIG) is extensively investigated as an artificial periodic structure in recent years owed to its simple reconfiguration and flexible adjustability. We report the experimental observation of EIG in cold rubidium atoms. The coupling and probe lasers are corresponding to the 5S1/2&minus, 5P1/2 and 5S1/2&minus, 5P3/2 transitions of a V-type electromagnetically induced transparency (EIT) configuration, respectively. A clear spatial intensity distribution of the probe laser with distinguished third-order diffraction pattern is recorded to character the EIG. The influence of the pertinent experimental parameters, such as coupling laser intensity and two-photon detuning on the diffraction pattern is investigated in detail. This is the first observation in visual form of the EIG in cold rubidium atoms. These results may potentially provide a nondestructive method to image cold atoms and pave the way for investigating non-Hermitian physics and the control of light dynamics.

Pulse diagnosis is one of the four diagnostic methods of traditional Chinese medicine. However it suffers from the lack of objective and efficient detection method. We propose a noncontact optical method to detect human wrist pulse, aiming at the precise determination of the temporal and spatial distributions of pulse. The method uses the spatial-carrier digital speckle pattern interferometry (DSPI) to measure the micro/nanoscale skin displacement dynamically. Significant improvements in DSPI measurement have been made to allow the DSPI to detect the comprehensive information of the arterial pulsation at locations of Cun, Guan, and Chi. The experimental results prove that the spatiotemporal distributions of pulse can be obtained by the proposed method. The obtained data can be further used to describe most of the pulse parameters such as rate, rhythm, depth, length, width, and contour.

A moving polygonal object takes up large storage space in moving database, which incurs heavy disk I/O cost in querying process. Motivated by TPR-tree and MR-tree, Multiple-Approximation is advanced to be TPMA with Time-Parameterized technology to deal with indexing of moving polygonal objects. New indexing structure for moving polygonal objects based on TPMA, which is termed as MTPR-tree, is presented in this paper. MTPR-tree uses TPBR and TPMEC to approximate moving polygon, which can decrease number of candidate results in a query. A hash structure is introduced into MTPR-tree to reduce negative effect of TPMA. Advantage of MTPR-tree is not only deduced theoretically, but also verified by extensive experiments in our study.

Branch and bound algorithm (2) was presented for NN query based on R-tree by N.Roussopoulos, S.Kelly and F.vincent in 1995. The process of the NN query is divided into two independent parts, search ordering and search pruning, by the algorithm in logic. The key to branch and bound algorithm to enhance the NN query is two metrics called MinDist and MinMaxDist. These two metrics can narrow the range used to approximately express the real distance between given object and spatial entity. King Lum Cheung and Ada Wai-Chee Fu proposed that MinMaxDist was not needed in the NN query (3), but Ravi K. Kothuri and Siva Ravada suggested it could work in the KNN query (4). The introduction of inside expression of spatial entity further narrow the range construct by MinDist and MinMaxDist. The minimum enclosing circle (MEC) of the DSB-tree is just one kind of inside expressions and also has the advantage of the circle in distance computing. We adjust branch and bound algorithm to suit to the DSB-tree and the main work is adjust the algorithms to get those two metrics. The advantage of DSB-tree in NN query is realized trough these two adjusted metrics. In the next section, the index structures and some algorithm used in NN query will be discussed. Then, DSB-tree and its basic operations will be introduced. In the section 4, we will present the algorithm of NN query for DSB-tree and the metrics of adjusted branch and bound algorithm. The extensive experiments and the discussion of the results will be given in the section 6. Finally, we will give the conclusion.