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The research on the structure of advanced electrode materials is significant in the field of supercapacitors. Herein, for the first time, we propose a novel 3D/3D composite structure by a multi-step process, in which 3D hollow NiCo LDH nanocages are immobilized on 3D sea urchin-like CoO microspheres. Results show that the 3D CoO acts as an efficient and stable channel for ion diffusion, while the hollow NiCo LDH provides abundant redox-active sites. The calculated results based on density function theory (DFT) show that the CoO@NiCo LDH heterostructure has an enhanced density of states (DOS) near the Fermi level and strong adsorption capacity for OH

In the common method of compiling outdoor design conditions by annual cumulative frequency of occurrence, the probability of simultaneous occurrence of the selected meteorological elements is not considered, which may lead to an overestimation of air-conditioning equipment capacity design. This paper aims at developing a novel approach for producing the outdoor design conditions, taking into consideration the dependency between the air temperature and global solar radiation, which have a strong influence on the HVAC capacity design. These two meteorological elements are analyzed for specific simultaneous occurrence probability based on the joint distribution. For this purpose, the copula approach which can describe the dependence between these two meteorological elements is used for modeling the joint distribution function. We investigated copula family selection for air temperature and global solar radiation at each hour of hourly weather data for 10 years from 2001 to 2010 in Osaka, Japan. The Joe-Frank copula has the best fitting results for the dependence between the air temperature and global solar radiation. According to the comparison of original exceeding probability and simultaneous occurrence probability, the results show that the design conditions based on the common method can significantly exceed that of the simultaneous occurrence probability method. Practical Application: Outdoor design conditions are used in the building design stage to estimate building performance and select the appropriate air conditioning equipment capacity. Excessive air-conditioning capacity may lead to a large amount of unnecessary energy wastage. Insufficient capacity may lead to not meeting the desired indoor environment conditions of utilization in extreme weather conditions, especially for large office buildings. Therefore, this paper provides a new approach to generate more realistic meteorological conditions for air-conditioning design to improve building energy efficiency.

With the development of society, the demand for mineral resources is gradually increasing, and the current situation of decreasing total resources dictates the inevitable interaction between open-pit combing underground extraction (OPUG) in time and space. In this research, we took the Anjialing coal mine in Shanxi Province of China as a case study, and tested the physical and mechanical properties of coal rocks in the laboratory. The similarity criterion was used to build a similar experimental model for the deformation evolution of the slope of the open-pit mine section; the digital scattering method was used to test the influence of the underground mining process parameters on the deformation evolution of the open-pit slope. The results showed that there was an obvious distribution of “three zones” above the mining goaf, namely, a collapse zone, fracture zone, and slow subsidence zone. When the mining face was continuously advanced towards the bottom of the open pit, the supporting stress of the mining face transferred to the side of the open-pit slope. Additionally, large displacement and stress concentration were observed on the slope near the stoping line, which caused the slope body to move along the uppermost part of the slope first, and thereafter along the lower part. Various techniques for slope stability control are discussed, including the optimization of spatial and temporal relationships between open-pit and underground mining, the optimization of mining plans, and the use of monitoring and early warning systems. The results can provide a guide for slope stability control of similar open-pit mines in the process of mining coal resources.

By using La(NO3)3•6H2O, Ca(NO3)2•4H2O, and Mn(CH3COO)2•4H2O as starting raw materials together with methanol, three kinds of La0.67Ca0.33MnO3 (LCMO) solutions, denoted as LCMO–BzAc, LCMO–AcAc, and LCMO–BPY, respectively, were obtained. The samples were fabricated via the photosensitive solution method with benzoylacetone (BzAc), acetylacetone (AcAc), and 2, 2′-bipyridine (BPY) as chelating reagents. The chelation mechanism of the metal ions was investigated via ultraviolet spectroscopy. The photosensitive compounds were decomposed after UV exposure and their products reduced the solubility of the LCMO gel films in organic solvents. The patterned LCMO thin films were then fabricated by using the self-photosensitive properties of their gel films. Through the mask micromachining process, the LCMO micropatterns prepared by using the LCMO–BzAc solution exhibited the highest quality. Moreover, they also presented good performance when the mask-free method was employed. The magnetic properties of the micropatterned LCMO films were investigated in detail and the results revealed that the micropatterning did not influence their saturation magnetization.

In this work, we prepared N-doped reduced graphene oxide/Co0.85Se (N-rGO/CS) microflowers through a two-step method. Since introducing N-doped rGO, the fabricated N-rGO/CS electrode with a high mass loading (~8.83 mg/cm2) exhibits high areal specific capacity of 0.522 mAh/cm2 (4.24 F/cm2) at 1 mA/cm2, and a long-term cycling stability (85.8% of capacity retention after 6000 charge-discharge cycles). This is mainly because N-doped rGO can increase specific area and electrical conductivity, enhance the electrochemical activity and effectively facilitate the electron/ion transport between the electrode and electrolyte. Besides, the quasi-solid-state hybrid supercapacitors (HSCs) assembled by the N-rGO/CS delivers a high volumetric specific capacity of 5.82 mAh/cm3 at 1 mA/cm2, excellent energy density of 4.65 mWh/cm3 under 10.5 mW/cm3 and eminement cycle stability (87.6% retention over 6000 cycles at 10 mA/cm2).

Low seed germination and seedling establishment are the greatest challenges for revegetation success. Topographic microsites are known to enhance seed germination and seedling establishment due to their unique soil properties and provision of shelter from elements and herbivores; soil amendments can supply organic matter and nutrients for plant establishment and growth when limited. We investigated the effect of three topographic microsites and six soil amendments and their additive effects on three disturbed grasslands in central and southern Alberta, Canada. Treatments were topographic microsites of mounds, pits, and flats, with and without amendments (erosion control blanket, hay, straw, manure, hydrogel, control) and were seeded with four native grasses and three native forb species. Seedling emergence and survival and soil temperature and water content were assessed over two seasons and plant cover over three seasons. The effect of microsites and amendments was not additive. The addition of erosion control blanket, hay, and straw to flat sites was just as productive as on topographic microsites. These amendments increased grass and forb emergence and buffered soil temperature. Mounds increased first year forb emergence and reduced over winter survival rates for grasses and forbs. Pits were not beneficial for revegetation. The effect of topographic microsites and amendments was influenced by site conditions.

Bi0.85La0.15Fe0.95Mn0.05O3 (BLFMO) gel films with benzoylacetone (BzAc) as a chelating reagent were fabricated on (00l) LaAlO3 (LAO) substrates using a photosensitive sol-gel method. The morphology, crystalline structure, electric and magnetic properties, and the grating-pattern of the films were investigated. The results showed that the epitaxial BLFMO films deposited on LAO single crystal substrates exhibit a higher degree of the c-axis orientation. The remnant polarization and saturation magnetization were found to be higher than those of the randomly oriented BLFMO films. Moreover, the gratings of the film with a period of 1 μm were obtained after exposure to two interference laser beams followed by leaching in ethanol. After treatment at 600 °C, the gel film turned into inorganic film gratings.

C-axis oriented La 0.67 Sr 0.33 MnO 3 (LSMO)/PbZr 0.52 Ti 0.48 O 3 (PZT) films are fabricated successfully by sol-gel method on LaAlO 3 (00 l ) substrates. The structure, composition and morphology of the films are investigated by X-ray diffractometer (XRD, θ-2θ scan, ω-scan and ϕ-scan), X-ray photoelectron spectroscope (XPS), field emission scanning electron microscope (FESEM) and high resolution transmission electron microscope (HRTEM). The electric and magnetic properties of randomly and c-axis oriented LSMO/PZT films are studied comparably using ferroelectric testing apparatus and physical property measurement system (PPMS). It is found that the epitaxial LSMO/PZT composite films show well controlled growth along c-axis, and much better magnetoelectric properties than the randomly oriented ones. The ME voltage coefficient increases from 23 mV cm − 1 Oe − 1 for the randomly oriented LSMO/PZT composite films to 52 mV cm − 1 Oe − 1 for c-axis oriented ones prepared using the low cost sol-gel method presented in this study, which shows high potential in promising applications.

A La2/3Sr1/3MnO3 (LSMO) photosensitive sol was synthesized using La(NO3)3•6H2O, Sr(CH3COO)2•0.5H2O, and Mn(CH3COO)2•4H2O as starting materials and benzoylacetone (BzAc) as a chelating agent, and the corresponding gel films were casted on single crystal LaAlO3 (00l) substrates. The complexation mechanism between metal ions and the chelating agent was investigated via Fourier transform infrared spectroscopy and ultraviolet-visible spectroscopy. The results show that the Mn and La ions were chelated with BzAc, and the as-cast gel film shows photosensitivity to ultraviolet-visible light. Grating-patterned films were prepared by irradiating the gel films for 3 min using a two-beam interference process followed by rinsing in a solution of isopropyl alcohol and n-butyl alcohol (2:1 v/v) for 8 s. It was found that the irradiated portion of the gel film remained intact in the solvent, whereas the unirradiated portion was dissolved, producing the gratings. The shape of the gratings is highly periodic without broken wires or defects. After annealing at 750 °C, the patterned LSMO gel film turned into a c-axis orientated inorganic film. The patterned LSMO film exhibited a saturation magnetization value that is similar to that of the unpatterned LSMO film.

A new coherent integration method involves Modified Keystone transform (KT) is proposed for the high speed maneuvering target with a constant jerk. Firstly, the range migration is corrected by the modified KT. Then Doppler frequency migration is compensated with the acceleration and jerk estimated by the modified dechirp process. Finally, the coherent integration is achieved by Fourier Transform. Compared with GRFT method [3],the proposed method has a much lower computational complexity and can avoid the interference of blind speed side lobe (BSSL).

The coherent integration problem for a space moving target with high-speed maneuvering performance is considered in this paper. The radial velocity, acceleration and jerk of the maneuvering target would result in the first-order range migration (FRM), second-order range migration (SRM) and third-order range migration (TRM) respectively within the coherent integration time. This paper proposes a novel long time coherent integration method based on generalized keystone transform (GKT) and Radon Fourier transform (RFT). Firstly, third-order and six-order keystone transform are used to correct TRM and SRM, respectively and the improved de-chirping method is utilized to compensate for the Doppler spread (DS). Then, residual range migration (RM) will be corrected by RFT. This algorithm can correct RM without knowing its motion information. The advantage of the proposed approach is that it can achieve the coherent integration under the condition of Doppler frequency ambiguity. The computational burden of the proposed method is less than that of GRFT algorithm. Finally, simulations are performed to demonstrate the validity of the proposed algorithm.

Integrated optical resonance gyroscope (IORG), with the ring resonator fabricated by micro-techniques, has the advantage of miniaturization, integration, and low cost. Theoretical calculation shows its potential ability in getting high sensitivity. However, the current IORG sensitivity is restricted by optical parasitical noises aggravated by involving high coherent laser source. Polarization fluctuation is one of the dominant noise sources in waveguide resonator. The effect on polarization noise in IORG by three main parameters: state of polarization of the input light, polarization-maintaining quality of the waveguide, and temperature fluctuation of the peripheral environment, has been theoretically analyzed and experimentally tested. An improved layout, with a Planar Lightwave Circuit (PLC) acting as both modulator and polarizer, is presented to suppress the polarization noise in IORG. The results show that the bias instability of IORG caused by polarization noise is greatly reduced from 1.57°/s to 0.005°/s.

Micro optical gyroscope has advantages of integrated optoelectronic technology. Its ring resonator is fabricated by optical integrated technique. Polarization fluctuation induced noise is one of the dominant noise sources in resonator. State of polarization of the input light, polarization-maintaining quality of the coupler and the waveguide, and the temperature fluctuation are main parameters which affect polarization noise of micro optical gyro. Simulations and validation experiments were made for these factors. As a countermeasure, an improved layout for the gyroscope is put forward to reduce the polarization noise, which includes a polarizer in front of the resonator and the polarization-maintaining waveguide resonator. Polarization-maintaining waveguide and coupler were designed according to the theory of geometrical birefringence. The improved layout provides theoretical basis and guidance for further development of the micro optical gyroscope.